Mycotoxins Bibliography Klaus Ammann WOS, 20110126

Abbas, H. K., W. C. A. Gelderblom, et al. (1993). "Biological-Activities of Fumonisins, Mycotoxins from Fusarium- Moniliforme, in Jimsonweed (Datura-Stramonium L) and Mammalian- Cell Cultures." Toxicon 31(3): 345-353. ://A1993KQ77900013 Fumonisins A1, A2, B1, B2 and B3 are a series of mycotoxins produced by strains of Fusarium moniliforme. Fumonisins are hydroxylated long-chain alkylamines esterified with propanetricarboxylic acid moieties that represent approximately half the mol. wt of the toxins. The A-series fumonisins are N- acetylated, whereas the B series contains free amino groups. Hydrolytic removal of the propanetricarboxylic acid moieties from fumonisins B1 an B2 yields the corresponding aminopentols, AP1 and AP2, respectively. These compounds were tested for toxicity on widely differing bioassay systems, representing plant and animal systems. The plant bioassay system employed jimsonweed (Datura stramonium L.) leaves and leaf discs in which toxicity was detected as electrolyte leakage, photobleaching and quantitation of chlorophyll reduction. The animal bioassay system employed cultured mammalian cell lines in which toxicity was detected as inhibition of cell proliferation. Fumonisins B1, B2 and B3 at 50 mug/ml or less were effective toxins after exposure periods greater than 24 hr in all plant and animal bioassay systems examined, except 3T3 mouse fibroblasts, whereas fumonisins A1 and A2 exhibited little or no activity. However, the hydrolytic degradation products AP1 and AP2 exhibited toxicity similar to or greater than B-series fumonisins in all test systems, including substantial toxicity to 3T3 mouse fibroblasts.

Abbas, H. K., W. T. Shier, et al. (2007). "Effet of temperature, rainfall and planting date on aflatoxin and fumonisin contamination, in commercial Bt and non-Bt-corn hybrids in Arkansas." Phytoprotection 88: 41-50. ://WOS:000253805400001 Corn (maize, Zea mays) is susceptible to contamination with aflatoxins, fumonisins and other mycotoxins, particularly in the southeastern USA. In principle, mycotoxin contamination could be reduced in commercial corn hybrids with shorter growing seasons by planting at dates which minimize plant stress during the critical kernel-filling period. To evaluate this strategy, commercial Bt and non-Bt hybrids were planted in Arkansas in mid-April and early May of 2002, 2004 and 2005. The mid-April planting date resulted in lower aflatoxin contamination in harvested corn each yr and in significantly less frequent contamination above a regulatory action level in 2005 and overall than did the early-May planting date in both Bt and non-Bt corn. The mid-April planting date resulted in significantly lower total fumonisin contamination in harvested corn and in less frequent contamination above a regulatory advisory level than the early May planting date in 2 of 3 yr and overall in both Bt and non-Bt corn. All fumonisin subtypes studied were reduced. Frequent co-occurrence of aflatoxin and fumonisin was observed. Fumonisin levels averaged lower in Bt hybrids than in non-Bt hybrids at all plantings. Reduced aflatoxin and fumonisin contamination with mid-April planting could not be explained by any measure of heat stress during the kernel-filling period.

Abbas, H. K., J. R. Wilkinson, et al. (2009). "Ecology of Aspergillus flavus, regulation of aflatoxin production, and management strategies to reduce aflatoxin contamination of corn." Toxin Reviews 28(2-3): 142-153. ://WOS:000269513700009 The contamination of corn (maize) by fungi and the accumulation of mycotoxins are a serious agricultural problem for human and animal health. One particular devastating group of mycotoxins, called aflatoxins, has been intensely studied since the 1960s. Studies of Aspergillus flavus, the agriculturally relevant producer of aflatoxins, have led to a well-characterized biosynthetic pathway for aflatoxin production, as well as a basic understanding of the organism's life cycle. Unfortunately, these efforts have not resulted in corn production practices that substantially reduce aflatoxin contamination. Similarly, the use of agrochemicals (e.g., fungicides) results in very limited reduction of the fungus or the toxin. Thus, cultural management (fertility and irrigation) coupled with aggressive insect management is current recommendation for integrated aflatoxin management. The development of resistant hybrids appears to be a very promising technology, but commercial hybrids are still not available. Thus, biocontrol appears to be the most promising available avenue of reducing aflatoxin accumulation. Biocontrol utilizes nontoxigenic strains of Aspergillus to reduce the incidence of toxin-producing isolates through competitive displacement. To maximize the effectiveness of biocontrol, a thorough knowledge of the environmental factors influencing colonization and growth of Aspergillus is needed. A. flavus not only colonizes living plant tissue, but it also grows saprophytically on plant tissue in the soil. These residues serve as a reservoir for the fungus, allowing it to overwinter, and under favorable conditions it will resume growth and release new conidia. The conidia can be transmitted by air or insects to serve as new inoculum on host plants or debris in the field. This complex ecology of Aspergilli has been studied, but our understanding lags behind what is known about biosynthesis of the toxin itself. Our limited understanding of Aspergilli soil ecology is in part due to limitations in evaluating Aspergilli, aflatoxin, and the biosynthetic genes in the varying aspects of the environment. Current methods for assessing Aspergillus and aflatoxin accumulation rely heavily on cultural and analytical methods that are low throughput and technically challenging. Thus to understand Aspergillus ecology and environmental effects in contamination to maximize biocontrol efforts, it is necessary to understand current treatment effects and to develop methodologies capable of assessing the fungal populations present. In this manuscript we discuss the current knowledge of A. flavus ecology, the application of selected molecular techniques to field assessments, and crop practices used to reduce aflatoxin contamination, focusing on chemical treatments (fungicides and herbicides), insect management, and crop management.

Abbas, H. K., W. P. Williams, et al. (2002). "Aflatoxin and fumonisin contamination of commercial corn (Zea mays) hybrids in Mississippi." Journal of Agricultural and Food Chemistry 50(18): 5246-5254. ://000177659300040 Resistance to mycotoxin contamination was compared in field samples harvested from 45 commercial corn (maize) hybrids and 5 single-cross aflatoxin-resistant germplasm lines in years with high and moderate heat stress. In high heat stress, mycotoxin levels were (4.34 +/- 0.32) x 10(3), mug/kg [(0.95-10.5 x 10(3), mug/kg] aflatoxins and 11.2 +/- 1.2 mg/kg (0-35 mg/kg) fumonisins in commercial hybrids and 370 +/- 88, mug/kg (140- 609, mug/kg) aflatoxins and 4.0 +/- 1.3 mg/kg (1.7-7.8 mg/kg) fumonisins in aflatoxin-resistant germplasm lines. Deoxynivalenol was detected (one-fourth of the samples, 0-1.5 mg/kg), but not zearalenone. In moderate heat stress, mycotoxin levels were 6.2 +/- 1.6, mug/kg (0-30.4,mug/kg) kaflatoxins and 2.5 +/- 0.2 mg/kg (0.5-4.8 mg/kg) fumonisins in commercial hybrids and 1.6 +/- 0.7, mug/kg (0-7 mug/kg) aflatoxins and 1.2 +/- 0.2 mg/kg (0.5-3.0 mg/kg) fumonisins in aflatoxinresistant germplasm lines. The results are consistent with heat stress playing an important role in the susceptibility of corn to both aflatoxin and fumonisin contamination, with significant reductions of both aflatoxins and fumonisins in aflatoxin- resistant germplasm lines.

Abedi, Z. H. and P. M. Scott (1969). "Detection of Toxicity of Aflatoxins, Sterigmatocystin, and Other Fungal Toxins by Lethal Action on Zebra Fish Larvae." Journal of the Association of Official Analytical Chemists 52(5): 963-&. ://WOS:A1969E252800020

Abel, S. and W. C. A. Gelderblom (1998). "Oxidative damage and fumonisin B-1-induced toxicity in primary rat hepatocytes and rat liver in vivo." Toxicology 131(2-3): 121-131. ://000078111000005 Dietary fumonisin B-1 (FB1) levels of 250 and 500 mg FB1/kg increased the level of thiobarbituric acid reactive substances (TBARS) significantly (P < 0.05) in the liver of rats fed FB1 over 21 days. Levels of 10, 50 and 100 mg FB1/kg also markedly (not significantly) increased the level of TEARS in the liver homogenate. Subcellular fractionation of the liver of the rats fed the 250 mg FB1/kg diet, showed a marginally significant increase of TEARS in the plasma membranes (0.05 < P < 0.1) and a significant increase in the microsomes (P<0.05). In vitro investigations in primary rat hepatocytes indicated that the level of TEARS was increased in a dose dependent manner associated with an increase in cytotoxicity. Addition of the antioxidant, a-tocopherol, significantly decreased the cytotoxicity whereas the level of TEARS was decreased to basal levels, suggesting that lipid peroxidation is likely to contribute to the cytotoxic effect of FB1. Addition of cumene hydroperoxide (CMHP) to primary hepatocytes exposed to FB1 for 44 h, enhanced the CMHP-induced TEARS release suggesting that the hepatocytes exposed to FB1 are more susceptible to chemically-induced oxidative stress. Free radical production could result in excessive cellular damage and/or metabolic abnormalities that are likely to be involved in FB1-induced altered growth responses and cell death in primary hepatocytes. The hepatotoxic effects and resultant oxidative damage induced by FB, may be important during cancer induction in rat liver by this apparently non-genotoxic compound. (C) 1998 Elsevier Science Ireland Ltd. All rights reserved.

Abnet, C. C., C. B. Borkowf, et al. (2001). "Sphingolipids as biomarkers of fumonisin exposure and risk of esophageal squamous cell carcinoma in China." Cancer Causes & Control 12(9): 821-828. ://000171398000007 Objective: Ecologic studies of esophageal squamous cell carcinoma (ESCC) have reported an association with consumption of maize contaminated with Fusarium verticillioides, which produce fungal toxins referred to as fumonisins. Fumonisins disrupt sphingolipid metabolism and serum sphingolipids have been proposed as biomarkers of fumonisin exposure. We conducted a prospective nested case-control study to examine the relationship between serum sphingolipids and ESCC incidence. Methods: Cases and controls were selected from a large prospective trial conducted in Linxian, People's Republic of China. Ninety-eight ESCC cases were randomly selected from the 639 incident ESCC ascertained during the initial 5.25 years of follow-up; 185 controls were also randomly selected based on the distribution of cases among six age and sex strata. Concentrations of sphinganine and sphingosine were determined by high-performance liquid chromatography in serum collected at the study baseline. Results: No significant associations were found between serum sphingosine, sphinganine, or the sphinganine/sphingosine ratio and ESCC incidence in conditional and unconditional logistic regression models with adjustment for age, sex, tobacco use, and alcohol use. Conclusion: Our study is the first prospective study to assess the relationship between sphingolipid levels, as biomarkers of fumonisin exposure, and cancer incidence. We found no significant association between sphingolipid levels and risk of ESCC.

Abou-Karam, M., H. K. Abbas, et al. (2004). "N-fatty acylation of hydrolyzed fumonisin B-1, but not of intact fumonisin B-1, strongly enhances in vitro mammalian toxicity." Journal of Toxicology-Toxin Reviews 23(1): 123-151. ://000220954300006 Fumonisin B-1 (FB1) is the most abundant of a series of sphingosine-analog mycotoxins produced by Fusarium verticilloides, the major fungal contaminant of stored corn (maize) world-wide. Fumonisins were originally isolated as environmental tumor promoters, and they remain a concern because they are frequent contaminants of corn-derived food products intended for direct human consumption. FB1 inhibits ceramide synthase, which may account for its acute toxic effects, but understanding of its tumor promotion mechanism has been limited by the general lack of understanding in the field. There is no evidence for functional metabolism of fumonisins in mammals, but abiogenic conversions during food processing are a concern because some known conversion products retain biological activity, including hydrolyzed FB1 (HFB1). HFB1, formed by alkaline removal of FB1 side chains, is a frequent contaminant of lime-treated corn products such as tortillas and tortilla chips. Humpf et al. (J. Biol. Chem., 273, 19060, 1998) observed that HFB1 not only inhibits ceramide synthase, but it is converted to a ceramide analog with about ten times the in vitro mammalian toxicity of intact FB1. In the present study we have confirmed this observation by preparing a series of ceramide analogs of HFB1 with varying fatty acid chain lengths and degree of unsaturation. Optimal in vitro mammalian toxicity was observed with fatty acid chain lengths of 10- 14 carbons. However, ceramide analogs of HFB1 were not phytotoxic in vitro, and ceramide analogs of FB1 were not toxic in either mammalian or plant in vitro bioassays.

Afolabi, C. G., P. S. Ojiambo, et al. (2007). "Evaluation of maize inbred lines for resistance to Fusarium ear rot and fumonisin accumulation in grain in tropical Africa." Plant Disease 91(3): 279-286. ://000244263500009 AND http://www.botanischergarten.ch/Bt/Alfolabi-Resistance-Fumonisin-2007.pdf Fusarium ear rot and fumonisin contamination is a major problem facing maize growers worldwide. and host resistance is the most effective strategy to control the disease, but resistant genotypes have not been identified. In 2003, a total of 103 maize inbred lines were evaluated for Fusarium ear rot caused by Fitsarium verticillioides in field trials in Ikenne and Ibadan, Nigeria Disease was initiated from natural infection in the Ikenne trial and from artificial inoculation in the Ibadan trial. Ear rot severity ranged from 1.0 to 6.0 in both locations in 2003. Fifty-two inbred lines with disease severity (.)3 (i.e., (.)10% visible symptoms on ears) were selected and re-evaluated in 2004 for car rot resistance, incidence of discolored kernels, and fumonisin contamination in grain. At both locations, car rot severity on the selected lines was significantly (P < 0.0020) higher in 2004 than in 2003. The effects of selected inbred lines on disease severity were highly significant at Ikenne (P = 0.0072) and Ibadan (P < 0.0001) in 2004. Inbred lines did not affect incidence of discolored kernels at both locations and across years except at Ikenne (P = 0.0002) in 2004. Similarly, significant effects of inbred lines on fumonisin concentration were observed only at Ikenne (P = 0.0201) in 2004. However, inbred lines 02C14585, 02C14593, 02C14603. 02C14606 02C14624, and 02C14683 had consistently low disease severity across years and locations. Fumonisin concentration was significantly correlated with ear rot only at Ikenne (R = 0.42. P < 0.0001). Correlation between fumonisin concentration and incidence of discolored kernels was also significant at Ikenne (R = 0.39, P < 0.0001) and Ibadan (R = 0.35, P = 0.0007). At both locations, no significant inbred x year interaction was observed for fumonisin concentration. Five inbred lines, namely 02C14585, 02C14603, 02C14606, 02C14624, and 02C14683, consistently had the lowest fumonisin concentration in both trials. Two of these inbred lines. 02C14624 and 02C14585, had fumonisin levels < 5.0 mu g/g across years in trials where disease was initiated from both natural infection and artificial inoculation. These lines that had consistently low disease severity are useful for breeding programs to develop fumonisin resistant lines.

Ajanwachukwu, J. and S. O. Emejuaiwe (1994). "Aflatoxin-Producing Fungi Associated with Nigerian Maize." Environmental Toxicology and Water Quality 9(1): 17-23. ://A1994MT49300003

Alberts, J. F., W. C. A. Gelderblom, et al. (1990). "Effects of Temperature and Incubation Period on Production of Fumonisin-B1 by Fusarium- Moniliforme." Applied and Environmental Microbiology 56(6): 1729-1733. ://A1990DG92200037

Alberts, J. F., W. C. A. Gelderblom, et al. (1993). "Production of C-14 Fumonisin-B(1) by Fusarium-Moniliforme Mrc-826 in Corn Cultures." Applied and Environmental Microbiology 59(8): 2673-2677. ://A1993LP83500049 Kinetics of growth and fumonisin production by Fusarium moniliforme MRC 826 in corn ''patty'' cultures were investigated, and a technique was developed for the production of [C-14]fumonisin B1 ([C-14]FB1) by using L-[methyl-C- 14]methionine as the precursor. A significant (P < 0.01) correlation exists between fungal growth and FB1 (r = 0.89) and FB2 (r = 0.87) production in corn patties, beginning after 2 days and reaching the stationary phase after 14 days of incubation. [C-14]FB1 was produced by adding L- [methyl-C- 14]methionine daily to cultures during the logarithmic phase of production. Incorporation of the isotope occurred at C-21 and C-22 of the fumonisin molecule and was enhanced in the presence of unlabeled L-methionine. Although the concentration of exogenous unlabeled methionine is critical for incorporation of the C-14 label, optimum incorporation was achieved by adding 50 mg of unlabeled L-methionine and 200 muCi Of L-[methyl-C- 14]methionine to a corn patty (30 g) over a period of 9 days, yielding [14C]FB, with a specific activity of 36 muCi/mmol.

Allah, E. M. F. (1998). "Occurrence and toxigenicity of Fusarium moniliforme from freshly harvested maize ears with special references to fumonisin production in Egypt." Mycopathologia 140(2): 99-103. ://000074202500006 http://www.botanischergarten.ch/Mycotoxins/Allah-Fusarium-1998.pdf Using the seed-plate technique, 18 different isolates of Fusarium moniliforme were isolated on pentachloronitrobenzene (PCNB) agar medium from 18 samples of a local variety of corn collected from locations in Minia Governorate. The isolates of F moniliforme were screened for their ability to produce fumonisins on polished rice grains using the solid state fermentation technique. Based on thin layer chromatographic (TLC) analyses using silica gel plates, 14 of the 18 isolates tested produced FB1 and FB2 with R-f (0.17) and (0.24), respectively. Concentration of FB1 was estimated using high performance liquid chromatography (HPLC). Production of FB1 by the 14 isolates of F. moniliforme tested ranged from 69 to 4495 ppm indicating that mouldy corn may represent a health hazard to consumers.

Almeida, A. P., B. Correa, et al. (2000). "Mycoflora and aflatoxin/fumonisin production by fungal isolates from freshly harvested corn hybrids." Brazilian Journal of Microbiology 31(4): 321-326. ://000168374000016 The mycoflora of 3 hybrids of freshly harvested corn grains collected from three regions of the state of Sao Paulo, Brazil (Assis, Capao Bonito and Ribeirao Preto) was investigated. A total of 66 samples were analyzed focusing on the influence of abiotic factors (moisture content, water activity, temperature and rainfall) on both the prevalence of Aspergillus flavus and Fusarium moniliforme, and the ability of these genera isolates to produce aflatoxins and fumonisins, respectively. In the three surveyed regions, the fungal population comprised mainly Fusarium spp., Penicillium spp., Aspergillus spp. and 2 others filamentous fungal genera, which were isolated from corn kernels showing water activity of 0.30 to 0.99 and moisture content of 5.0% to 20.2%. Among the genera Fusarium and Aspergillus, the most frequent species were F. moniliforme and A. flavus, respectively. Concerning the toxigenic potential of F. moniliforme, all isolated strains (40) produced fumonisins at 20 mug/g to 2168 mug/g (FB1) and/or 10 mug/g to 380 mug/g (FB2). From the 10 A. flavus isolates, 6 strains (60.0%) produced aflatoxins at 615 mug/kg to 30.750 mug/kg (AFB(1)) and/or 11 mug/kg to 22 mug/kg (AFB(2)).

Almeida, A. P., H. Fonseca, et al. (2002). "Mycoflora and fumonisin contamination in Brazilian corn from sowing to harvest." Journal of Agricultural and Food Chemistry 50(13): 3877-3882. ://000176267800041 The present study aimed to analyze the mycoflora and potential mycotoxin contamination of soil and corn samples collected at different plant maturity stages in Capao, Bonito and Ribeirao Preto, two regions of the State of Sao Paulo, Brazil. In addition, the data obtained were correlated with the occurrence of wind-dispersed fungi and the predominant climatic conditions of the two regions studied. Corn mycoflora profiles showed that Fusarium verticillioides prevailed in 35% of the samples from Capao Bonito and in 49% of the samples from Ribeirao Preto. Examination of wind-dispersed fungi also revealed a high incidence of F verticillioides. Soil mycoflora analyses showed that Penicillium was the most prevalent genus, although F verticillioides was present in 55.5% of Capao, Bonito's samples and in 26.7% of Ribeirao Preto's samples. With respect to water activity, the corn kernels most contaminated with F verticillioides had water activity levels of 0.70-0.80. HPLC analysis of fumonisins revealed that 88.5% of Capao Bonito's kernels were contaminated with fumonisin B-1 (FB1) (0.09-10.87 mug/g) and 53.8% with fumonisin B-2 (FB2) (0.05-0.52 mug/g); Ribeirao Preto's kernels presented contamination levels of 93.5% for FB1 (0.11-1 7.69 mug/g) and 61.3% for FB2 (0.05-5.24 mug/g). No aflatoxins were detected by thin-layer chromatography in corn grains of either region. The concomitant occurrence of F. verticillioides and fumonisins in most of the field corn assayed demonstrates the importance of an effective control of cultivation throughout the plant maturity stages.

Aly, S. E. (2002). "Distribution of aflatoxins in product and by-products during glucose production from contaminated corn." Nahrung-Food 46(5): 341-344. ://000178827700009 Afllatoxins are known to be hepatotoxic, carcinogenic, and teratogenic. A positive correlation has been established between the consumption of aflatoxin-contaminated foods and the increased incidence of liver cancer worldwide. A survey of Egyptian corn and corn-based products and by-products shows that the majority of the samples had higher limits of aflatoxin. We have conducted experiments to determine the fate and distribution of aflatoxin during wet-milling process fractions and investigate the aflatoxin destruction during starch conversion to glucose syrup. The present results showed that about half of the aflatoxin content (48.1%) in the infected corn grain was found to be lost in steep liquor, depending upon the aflatoxin type, arranged in the order G(1) > G(2) > B- 1 > B-2. After wet-milling aflatoxins were distributed into starch, gluten, fiber, and germ. Gluten, fiber, and germ were the most highly contaminated fractions. The loss of aflatoxin during process of starches reached 54.4% in steep water and water process. Although the gluten fraction represents only 9.6% of corn, the higher percentage (25.3%) of aflatoxin was found in this fraction, the fiber and germ account for nearly 29% of the milled corn and contain 11.6% of the aflatoxin. On the other hand, 8.7% of the total aflatoxins in start corn was found in starch fraction which accounts 61% of the milled corn. Aflatoxins G(1) and G(2) were found lost in higher concentrations compared to the aflatoxin B-1 and B-2. A higher percentage of AfG(1) (86.35%) and AfG(2) (78.36%) and a lower percentage of AfB(1) (16.3%) and AfB(2) (14.7%) were found in starch fraction. The conversion percent of contaminated starch was 89.5% compared with control starch. It can be concluded that aflatoxins were destroyed during starch conversion. Consequently, glucose syrup produced from contaminated starch was found aflatoxin-free.

Amalfitano, C., R. Pengue, et al. (2002). "HPLC analysis of fusaric acid, 9,10-dehydrofusaric acid and their methyl esters, toxic metabolites from weed pathogenic Fusarium species." Phytochemical Analysis 13(5): 277-282. ://000178418000008 A simple and rapid HPLC method, using a high-density C-18 column, has been developed for the quantitative analysis of fusaric and dehydrofusaric acids and their methyl esters in the methanol extract of lyophilised culture filtrates of species of Fusarium. The method has been used to determine the content of these metabolites in two strains of Fusarium oxysporum and in strains of F. nygamai and F. udum. Fusaric acid has been isolated and identified from a strain of F. udum for the first time. Copyright (C) 2002 John Wiley Sons, Ltd.

Annis, S. L., L. Velasquez, et al. (2000). "Novel procedure for identification of compounds inhibitory to transcription of genes involved in mycotoxin biosynthesis." Journal of Agricultural and Food Chemistry 48(10): 4656-4660. ://000089957200032 A novel assay is described for the identification and isolation of compounds that inhibit the transcription of genes involved in mycotoxin biosynthesis. The thin-layer chromatography-based assay was used to screen plant extracts for compounds that would inhibit the expression of the beta -glucuronidase reporter gene under the control of an aflatoxin biosynthesis gene promoter in Aspergillus parasiticus. The assay was used to track purification of an inhibitory compound, cp2, from extracts of black pepper (Piper nigrum). Cp2 did not inhibit mycelial growth or the expression of the beta -tubulin gene but did inhibit aflatoxin biosynthesis at the transcriptional level. Applications of cp2 to the control of mycotoxins are discussed.

ApSimon, J. W. (2001). "Structure, synthesis, and biosynthesis of fumonisin B-1 and related compounds." Environmental Health Perspectives 109(2 supplement): 245-249. ://WOS:000168824500010 AND http://www.botanischergarten.ch/Bt/ApSimon-Structure-Fumonisin-2001.pdf The absolute stereochemical description of fumonisin B-1 (FB1) and presumably of its congeners is now secure. In this article I summarize studies leading to this conclusion and outline the biosynthetic and synthetic studies of FB1.

Apsimon, J. W., B. A. Blackwell, et al. (1994). "Relative Configuration of the C-1 to C-5 Fragment of Fumonisin B-1." Tetrahedron Letters 35(42): 7703-7706. ://A1994PM95300001 Synthesis of the 2,3-carbamate (2) and the 3,5-carbonate-N-p- bromobenzoate (4) derivatives of fumonisin B-1 have been made in an initial study of the configuration of fumonisins. These have been used to determine the relative configuration of the C(1)-C(5) fragment.

Apsimon, J. W., B. A. Blackwell, et al. (1994). "The Chemistry of Fumonisins and Related-Compounds - Fumonisins from Fusarium-Moniliforme - Chemistry, Structure and Biosynthesis." Pure and Applied Chemistry 66(10-11): 2315-2318. ://A1994PM11400080 Recent work on the biosynthesis and stereochemical determinations of the fumonisin structure and the determination of related compounds is presented.

Aranda, M., L. Perez-Alzola, et al. (2000). "Assessment of in vitro mutagenicity in Salmonella and in vivo genotoxicity in mice of the mycotoxin fumonisin B-1." Mutagenesis 15(6): 469-471. ://000165727300003 Fumonisin B-1 (FB1), a mycotoxin produced by Fusarium moniliforme, is a contaminant of cereals with various and complex cellular effects. FB1 induces liver cancer in rats and has been linked to esophageal cancer in South Africa and China. The mechanisms of FB1- induced carcinogenesis are uncertain and the information on FB1 mutagenic properties is limited and controversial. FB1 contamination levels in maize and wheat from Chile were found to be similar to those in other countries. FB1 was devoid of activity in gene mutation assays with Salmonella typhimurium strains TA100, TA102 and TA98. However, i.p. injection of FB1 induced an increased frequency of micronuclei in mouse bone marrow polychromatic erythrocytes at 25 and 100 mg/kg. We conclude that FBI induces in vivo genotoxicity in the absence of in vitro mutagenicity in Salmonella.

Armbrech.Bh, W. T. Shalkop, et al. (1970). "Acute Toxicity of Aflatoxin B1 in Wethers." Nature 225(5237): 1062-&. ://WOS:A1970F629500052

Arranz, I., W. R. G. Baeyens, et al. (2004). "Review: HPLC determination of fumonisin mycotoxins." Critical Reviews in Food Science and Nutrition 44(3): 195-203. ://000221761000005 An overview of liquid chromotogrophic methods, mainly employing fluorescence detection together with sample pre-treatment methods, is presented,for the determination of the toxic group of fumonisin mycotoxins in various matrices.

Asran, M. R. and H. Buchenauer (2002). "Virulence of Fusarium moniliforme isolates on maize plants in relation to fumonisin and ergosterol levels." Zeitschrift Fur Pflanzenkrankheiten Und Pflanzenschutz-Journal of Plant Diseases and Protection 109(5): 491-505. ://000178639300005 Fusarium moniliforme is considered as one of the most important fungal pathogens of maize and may cause seedling blight, stalk and ear rot. Of 32 F. moniliforme isolates obtained from naturally infected maize plants, six isolates were subjected to PCR-analysis using species-specific primers. In growth chamber experiments following seed inoculation, all isolates caused pre- and post- emergence death of maize seedlings. Dry weights of infected seedlings were markedly reduced compared to uninoculated control seedlings. The F. moniliforme isolates varied in seedling disease severities. Eleven isolates of F. moniliforme selected and one isolate of F. graminearum were tested for their stalk and ear rot pathogenicity under field conditions using the toothpick inoculation method. Stalk rot symptoms were produced by all isolates, however, they differed in their degree of pathogenicity. Positive correlation between seedling blight severity and stalk rot symptoms was observed. The reaction of maize cultivars varied in their stalk rot sensitivity and no significant interactions among isolates and cultivars could be observed. Resistance of maize cultivars to stalk rot was not associated with ear rot. Six isolates were examined with regard to possible relations between seedling blight severity and fumonisin production as well as to ergosterol levels in the infected tissues. While in the most and least virulent isolates fumonisin and ergosterol contents in the seedlings was associated with disease severity, in the isolates with middle virulence no relations between these parameters were found.

Avantaggiato, G., F. Quaranta, et al. (2003). "Fumonisin contamination of maize hybrids visibly damaged by Sesamia." Journal of the Science of Food and Agriculture 83(1): 13-18. ://000180409900003 Sesamia nonagrioides Lefebvre (Lepidoptera: Noctuidae) is the main insect pest of maize cultivated in Mediterranean areas, causing an increase in broken plants, a reduction in yield and a decline in grain quality. An investigation of Sesamia attacks and fumonisin accumulation on 25 maize hybrids sown as a second crop after wheat has been performed under field conditions in Central Italy in 2000. The hybrids tested in this study showed different degrees of insect damage, ranging from 12 to 57% of damaged ears per hybrid. Over 50% of the tested hybrids showed strong insect damage, with more than 30% of harvested ears visibly damaged by Sesamia. Fungal contamination by Fusarium verticillioides and F proliferatum, two well-known producers of fumonisins, was detected in both symptomless and insect-damaged samples. Fumonisin analysis of healthy-looking and insect- damaged ear samples of each hybrid showed 100% incidence of positive samples, with fumonisin contents ranging from 0.01 to 20 mg kg(-1) for healthy- looking ears and from 27 +/- 32 to 287 +/- 221 mg kg(-1) for insect-damaged ears. Extremely high levels of fumonisins were found in ear samples visibly damaged by Sesamia, with individual values of up to 694 mg kg (-1) and average values exceeding 100 mg kg(-1) in more than 50% of the hybrids. A good correlation (r = 0.749) was found between fumonisin contamination and the degree of insect damage by Sesamia of the tested hybrids, calculated on the basis of percentage of ears visibly damaged by insects and with more than 5% kernel loss. This finding leads to the conclusion that insect damage by Sesamia on maize could be used as an early indicator of fumonisin contamination. (C) 2002 Society of Chemical Industry.

Awad, W. A., K. Ghareeb, et al. (2008). "The Impact of the Fusarium Toxin Deoxynivalenol (DON) on Poultry." International Journal of Poultry Science 7(9): 827-842. http://www.pjbs.org/ijps/fin1165.pdf AND http://www.botanischergarten.ch/Bt/Awad-Impact-Fumonisin-Poultry-2008.pdf Deoxynivalenol (DON), a trichothecene, is prevalent worldwide in crops used for food and feed production. The presence of mycotoxins in poultry feeds is a significant factor for financial losses to animal industries. Although DON is one of the least acutely toxic trichothecenes, it should be treated as an important food safety issue because it is a common contaminant of grains. Special care must be taken in so-called “Fusarium years”. As poultry is regarded to be less sensitive to DON compared to other species it is suspected to divert the infected cereal batches to poultry feeding. This review focuses on the ability of DON to induce toxicologic and immunotoxic effects in chickens. Chickens and laying hens respond to increasing dietary DON concentrations with a reduction in productivity only at high levels above 5mg/kg but there is no clear evidence of a dose-response relationship. The main effect at low dietary concentrations appears to be a reduction in food consumption (anorexia), while higher doses induce severe reduction in weight and impaired resistance to infection, particularly bacterial infection. One important aspect of DON toxicity is injury to the gastrointestinal tract. DON has an influence intestinal morphology of chickens, especially in the duodenum and jejunum, as evidenced by shorter and thinner villi. Additionally, DON decreased the intestinal nutrients absorption (glucose and amino acid) in the chicken small intestine in vivo and In vitro. The capacity of DON to alter normal immune function has been of particular interest. There is extensive evidence that DON impairs the immune function in broiler and Leghorn chicks. DON induced changes in the haematopoietic system of chicks and altered the mitogen-induced proliferation of lymphocytes. The feeding of DON contaminated grains decreases serum antibody titers against Newcastle disease virus (NDV) and infectious bronchitis virus (IBV) in laying hens and broilers. Other effects include superinduction of cytokine production by T helper cells (In vitro) and activation of T cells to produce a proinflammatory cytokine. To what extent the elevation of cytokines contributes to metabolic effects such as decreased feed intake remains to be established. Further toxicological studies on the impact of DON in the immune system and gastrointestinal tract of poultry are warranted.

Aziz, N. H., S. A. El-Zeany, et al. (2002). "Influence of gamma-irradiation and maize lipids on the production of aflatoxin B-1 by Aspergillus flavus." Nahrung-Food 46(5): 327-331. ://000178827700006 The effect of gamma-irradiation and maize lipids on aflatoxin B, production by Aspergillus flavus artificially inoculated into sterilized maize at reduced water activity (a(w) 0.84) was investigated. By increasing the irradiation doses the total viable population of A. flavus decreased and the fungus was completely inhibited at 3.0 kGy. The amounts of aflatoxin B, were enhanced at irradiation dose levels 1.0 and 1.5 kGy in both full-fat maize (FM) and defatted maize (DM) media and no aflatoxin B-1 production at 3.0 kGy gamma- irradiation over 45 days of storage was observed. The level in free lipids of FM decreased gradually, whereas free fatty acid values and fungal lipase activity increased markedly by increasing the storage periods. The free fatty acid values decreased by increasing the irradiation dose levels and there was a significant enhancement of fungal lipase activity at doses of 1.0 and 1.50 kGy. The ability of A. flavus to grow at a(w) 0.84 and produce aflatoxin B-1 is related to the lipid composition of maize. The enhancement of aflatoxin B-1 at low doses was correlated to the enhancement of fungal lipase activity.

Aziz, N. H. and S. R. Mahrous (2004). "Effect of gamma-irradiation on aflatoxin B-1 production by Aspergillus flavus and chemical composition of three crop seeds." Nahrung-Food 48(3): 234-238. ://000222548400016 The effect of gamma-irradiation on aflatoxin B-1 production by Aspergillus flavus, and the chemical composition of some different crop seeds were investigated. A. flavus infected seeds behaved differently according to their principal constituents. A. flavus caused an increase in protein and decrease in lipids and carbohydrate contents of wheat, soyabean and fababean seeds. Growth of A. flavus and production of aflatoxin B-1 was inhibited at a dose level of 5 kGy. A. flavus utilizes carbohydrates of seeds for its growth and aflatoxin production. Crops were arranged, in descending order, according to aflatoxin produced in seeds as wheat > soyabcan > fababean. There were no changes in chemical constituents of irradiated seeds, such as protein, lipids, and carbohydrates.

Aziz, N. H. and B. Smyk (2002). "Influence of UV radiation and nitrosamines on the induction of mycotoxins synthesis by nontoxigenic moulds isolated from feed samples." Nahrung-Food 46(2): 118-121. ://000175245800015 The effects of UV radiation and nitrosamines on the induction of mycotoxin biosynthesis by some nontoxigenic moulds isolated from feed samples collected from Egypt and Poland A-as investigated. Nontoxigenic strains of Aspergillus flavus P-63, A. niger EN-200 and A. ochraceus P-157 synthesized mycotoxins (aflatoxins and ochratoxin, A) after exposure to near UV radiation for 120-210 min. Nitrosamines (DMNA. and DENA) at 30 up to 1000 ppm induced the synthesis of aflatoxins by nontoxigenic species of A. flavus ES- 255 and P-63 and A. niger EN 200. Near-UV radiation and nitrosamines had no influence on the induction of mycotoxin synthesis by Penicillium and Fusarium isolates. All nontoxigenic strains of Aspergilli which synthesized aflatoxins in the presence of 1000 ppm nitrosamines, also synthesized continuously aflatoxins during the next fifteen generations. Near-UV radiation and nitrosamines had a mutagenic effect on the induction of mycotoxins synthesis by nontoxigenic moulds.

Bacon, C. W. and D. M. Hinton (2002). "Endophytic and biological control potential of Bacillus mojavensis and related species." Biological Control 23(3): 274-284. ://000174354900009 The identity of a patented endophytic bacterium was established by 16S rRNA sequence analysis as a strain of Bacillus mojavensis, a recently erected species within one of the B. subtilis subgroups. This strain of B. mojavensis is antagonistic to the fungus Fusarium moniliforme, an endophytic, mycotoxin-producing pathogen of maize and other plants. There, are five other species within this subgroup: Bacillus amyloliquefaciens, B. atrophaeus, B. licheniformis, Brevibacterium halotolerans, Paenibacillus lentimorbus, and P. popilliae. The objectives of this research were to screen other isolates of B. mojavensis, B. subtilis, and the other closely related Bacillus species for endophytic colonizing capacity and to determine the in vitro antagonism to F. moniliforme in an effort to survey the distribution of these traits, which are desirable biological control qualities within the Bacillaceae. Antagonism was determined on nutrient agar, and endophytic colonization was established with maize plants following recovery of rifampin-resistant mutants generated from all strains used in the study. The study established that all 13 strains of B. mojavensis, isolated from major deserts of the world, endophytically colonized maize and were antagonists to F. moniliforme. The endophytic colonization of maize by R subtilis and other species within this subgroup of the Bacillaceae varied, as did antagonism, to F. moniliforme. Thus, this study suggests that endophytic colonization is another characteristic of the species B. mojavensis. The endophytic habit and demonstrated antagonism to the test fungus indicate that isolates of this species might prove to be important biological control organisms where the endophytic habit is desired.

Bacon, C. W. and P. E. Nelson (1994). "Fumonisin Production in Corn by Toxigenic Strains of Fusarium- Moniliforme and Fusarium- Proliferatum." Journal of Food Protection 57(6): 514-521. ://A1994NR98700013

Bacon, C. W., I. E. Yates, et al. (2001). "Biological control of Fusarium moniliforme in maize." Environmental Health Perspectives 109(2 supplement): 325-332. ://WOS:000168824500021 AND http://www.botanischergarten.ch/Bt/Bacon-Biological-Control-Fumonisin-2001.pdf Fusarium moniliforme Sheldon. a biological species of the mating populations within the Gibberella fujikuroi species complex, i.e., population A [= G. moniliformis (Sheld.) Wineland], is an example of a facultative fungal endophyte. During the biotrophic endophytic association with maize, as well as during saprophytic growth, F. moniliforme produces the fumonisins. The fungus is transmitted vertically and horizontally to the next generation of plants via clonal infection of seeds and plant debris. Horizontal infection is the manner by which this fungus is spread contagiously and through which infection occurs from the outside that can be reduced by application of certain fungicides. The endophytic phase is vertically transmitted. This type infection is important because it is not controlled by seed applications of fungicides, and it remains the reservoir from which infection and toxin biosynthesis takes place in each generation of plants. Thus, vertical transmission of this fungus is just as important as horizontal transmission. A biological control system using an endophytic bacterium, Bacillus subtilis, has been developed that shows great promise for reducing mycotoxin accumulation during the endophytic (vertical transmission) growth phase. Because this bacterium occupies the identical ecological niche within the plant, it is considered an ecological homologue to F. moniliforme, and the inhibitory mechanism, regardless of the mode of action, operates on the competitive exclusion principle. In addition to this bacterium, an isolate of a species of the fungus Trichoderma shows promise in the postharvest control of the growth and toxin accumulation from F. moniliforme on corn in storage.

Bakan, B., D. Melcion, et al. (2002). "Fungal growth and Fusarium mycotoxin content in isogenic traditional maize and genetically modified maize grown in France and Spain." Journal of Agricultural and Food Chemistry 50(4): 728-731. ://000173783700013 MAINTENANCE 20080316 Fungi of the genus Fusarium, are common fungal contaminants of maize and are also known to produce mycotoxins. Maize that has been genetically modified to express a Bt endotoxin has been used to study the effect of insect resistance on fungal infection of maize grains by Fusarium species and their related mycotoxins. Maize grain from Bt hybrids and near-isogenic traditional hybrids was collected in France and Spain from the 1999 crop, which was grown under natural conditions. According to the ergosterol level, the fungal biomass formed on Bt maize grain was 4-18 times lower than that on isogenic maize. Fumonisin B, grain concentrations ranged from 0.05 to 0.3 ppm for Bt maize and from 0.4 to 9 ppm for isogenic maize. Moderate to low concentrations of trichothecenes and zearalenone were measured on transgenic as well as on non-transgenic maize. Nevertheless, significant differences were obtained in certain regions. The protection of maize plants against insect damage (European corn borer and pink stem borer) through the use of Bt technology seems to be a way to reduce the contamination of maize by Fusarium species and the resultant fumonisins in maize grain grown in France and Spain.

Bandyopadhyay, R., M. Kumar, et al. (2007). "Relative severity of aflatoxin contamination of cereal crops in West Africa." Food Additives and Contaminants 24(10): 1109-1114. ://WOS:000250351500010 Aflatoxins are a common contaminant of cereals that can cause cancer, liver disease, immune suppression, retarded growth and development, and death, depending on the level and duration of exposure. Maize is an introduced crop to Africa and there have been efforts over the last 20 years or so to replace traditional cereal crops, such as sorghum ( Sorghum bicolor) and pearl millet ( Pennisetum glaucum), with maize. We found that maize was significantly more heavily colonized by aflatoxin- producing Aspergillus spp. than either sorghum or millet, with overall aflatoxin levels being correspondingly higher. On average, Nigerians consume 138 kg cereals annually. If the primary cereal is sorghum instead of maize, then the risk of aflatoxin- related problems is reduced 4- fold; if it is pearl millet, then the risks are reduced 8- fold. Development programs and other ventures to increase maize production in marginal cropping areas of Africa should be reconsidered and, instead, efforts to improve/maintain traditional crops encouraged.

Bankole, S. A. and O. O. Mabekoje (2004). "Mycoflora and occurrence of aflatoxin B-1 in dried yam chips from markets in Ogun and Oyo States, Nigeria." Mycopathologia 157(1): 111-115. ://000188120500014 Seventy-six samples of dried yam chips locally called elubo isu were purchased in 2000 from markets in Ogun and Oyo States of southwestern Nigeria. The samples were assessed for pH, moisture content, associated fungi and aflatoxin B-1 contamination. The pH of samples ranged from 5.6 to 6.1, while the moisture contents varied from 6.8 to 14.5% in Ogun samples, and 7.1 to 13.6% in samples from Oyo. Aspergillus and Penicillium were the two prevalent genera of fungi, and the number of colony forming units per gram of these two genera in the yam chips studied exceeded the tolerance limit in foodstuffs. The other fungal genera isolated included Botryodiplodia, Cladosporium, Fusarium, Rhizopus, Mucor, Aureobasidium and Paecilomyces. The two most frequent fungal species were A. niger and A. flavus. Thin layer chromatographic analysis showed that 17 samples or 22% contained aflatoxin B-1 beyond the detection limit (5 ppb), but only three samples or 4% had toxin level above 30 ppb, the tolerance level in food for human consumption. The mean concentration of aflatoxin B-1 in positive samples was 27.1 ppb.

Bankole, S. A. and O. O. Mabekoje (2004). "Occurrence of aflatoxins and fumonisins in preharvest maize from south-western Nigeria." Food Additives and Contaminants 21(3): 251-255. ://000189258000007 A survey was conducted on the incidence of fungi, and the natural occurrence of aflatoxins and fumonisins in preharvest maize from fields in south-western Nigeria. Mycological examinations revealed the predominance of F. verticillioides ( Zea mays ) (syn. F. moniliforme ), occurring in 89.3% of samples with a mean kernel infection of 49.4%, while Aspergillus flavus was isolated from 65% of samples having a mean kernel infection of 6.8%. Aflatoxin B-1 was detected in 18.4% of samples with a mean of 22 mug kg(-1) , while aflatoxins B-2 , G(1) and G(2) were present in 7.8, 2.9 and 1% of the samples with mean levels of 10, 8 and 7 mug kg(-1) , respectively, in contaminated samples. Total aflatoxins ranged from 3 to 138 mug kg(-1) in positive samples, with a mean of 28 mug kg(-1) . Fumonsin B-1 was the predominant toxin detected in terms of frequency (78.6% of samples) and quantity (concentration range 70-1780 mug kg(-1) , mean = 495 mug kg(- 1)). Fumonisin B-2 was detected in 68 samples (66%) with a mean of 114 mug kg(- 1) . Fifteen samples were contaminated with both aflatoxins and fumonisins.

Barnes, S. E., T. P. Dola, et al. (1994). "Synthesis of Sterigmatocystin on a Chemically-Defined Medium by Species of Aspergillus and Chaetomium." Mycopathologia 125(3): 173-178. ://A1994NT10600007 Sterigmatocystin (ST) is a secondary metabolite and a principal mycotoxin known to be produced by over 30 species of filamentous fungi. It is also one of the late intermediates in aflatoxin biosynthesis. We have tested the ability of 7 species of Aspergillus, including 4 strains of A. versicolor, one species of Bipolaris, and two species of Chaetomium, to produce ST on a sucrose-salts-phenylalanine defined medium as well as on three complex substrates. Highest ST production in our survey was by a strain of A. versicolor grown on wheat, whereas, the highest ST production on defined medium was by C. cellulolyticum. To our knowledge, this is the first report of ST production by C. cellulolyticum on any substrate. In precursor feeding studies, resting cultures of wild type A. nidulans and A. versicolor were unable to biotransform O- methylsterigmatocystin (OMST), the last known intermediate in aflatoxin biosynthesis. These results suggest that ST is the end product of polyketide metabolism in the strains tested.

Becker, B., H. Bresch, et al. (1997). "The effect of fumonisin B-1 on the growth of bacteria." World Journal of Microbiology & Biotechnology 13(5): 539-543. ://A1997XX40600009

Beekrum, S., R. Govinden, et al. (2003). "Naturally occurring phenols: a detoxification strategy for fumonisin B-1." Food Additives and Contaminants 20(5): 490-493. ://000183421500009 Phenolic compounds from plants offer a means for both the prevention and detoxification of mycotoxins that affect human health. This research investigates the control of fungal growth and toxin production by Fusarium verticillioides with plant phenolic compounds, namely chlorophorin, iroko and maakianin, benzoic acid, caffeic acid, ferulic acid, and vanillic acid. Inhibition by these compounds of fungal growth was determined by the agar overlay method and their affect on fumonisin B-1 (FB1) production was determined by high-performance liquid chromatography. Chlorophorin was the most effective compound in inhibiting fungal was the most e growth, followed by iroko, maakianin, vanillic acid and caffeic acid. Chlorophorin also was the most effective compound in reducing toxin production (94% reduction), followed by caffeic acid, ferulic acid, vanillic acid and iroko, which reduced FBI levels by 90-91%. The widespread occurrence of fumonisins world-wide and the lack of adequate prevention of fumonisins require 'biologically safe' alternatives to prevent the transfer of fungi and their health hazardous toxins into our daily foods and environment.

Bennett, J. W., P. K. Chang, et al. (1997). One gene to whole pathway: The role of norsolorinic acid in aflatoxin research. Advances in Applied Microbiology, Vol 45. San Diego, ACADEMIC PRESS INC. 45: 1-15. ://A1997BJ87Q00001

Betran, F. J. and T. Isakeit (2004). "Aflatoxin accumulation in maize hybrids of different maturities." Agronomy Journal 96(2): 565-570. ://000220382200030 The incidence and severity of preharvest aflatoxin is greater under drought conditions, which commonly occur late in the growing season of south and central Texas. To determine if early maturation could be used as a means of disease escape, aflatoxin contamination was measured in early-, intermediate-, and full-season commercial hybrids at two Texas locations, Weslaco and College Station. The early and intermediate hybrids chosen are primarily marketed in midwestern USA while the full- season hybrids are primarily marketed in southeastern USA. Hybrids were evaluated by inoculating ears 6 to 10 d after midsilk with Aspergillusflavus NRRL 3357 using the silk channel technique and measuring aflatoxin in harvested grain using the VI-CAM Aflatest procedure. Across locations, full-season hybrids had lower aflatoxin (mean = 777 ng g(-1)) levels than intermediate (mean = 1668 ng g-1) and early (mean = 1899 ng g(- 1)) hybrids. There was an inverse correlation between silking date and aflatoxin levels at both locations (r = - 0.59, P = 0.01 at College Station and r = -0.58, P = 0.01 at Weslaco). Early and intermediate hybrids had looser husk coverage than full-season hybrids, a characteristic that was positively correlated with aflatoxin levels at both locations. At both locations, grain yield was lower with early and intermediate hybrids than with full-season hybrids. Early maturation in hybrids was insufficient by itself to reduce aflatoxin contamination, but it should be re-evaluated using early maturing hybrids that have good agronomic adaptation to these two Texas growing conditions.

Betran, F. J., T. Isakeit, et al. (2002). "Aflatoxin accumulation of white and yellow maize inbreds in diallel crosses." Crop Science 42(6): 1894- 1901. ://000181430200018 Preharvest aflatoxin (AF) contamination is one of the main limitations for corn (Zea mays L.) production in the southern USA causing enormous economic losses and posing a risk to animal and human health. The objectives of this study were (i) to evaluate and compare hybrids of new and selected potential sources of AF resistance for AF accumulation under field conditions, (ii) to identify the inbreds with the most consistent expression of resistance under different hybrid combinations and growing conditions; and (iii) to estimate combining abilities of white and yellow inbreds for aflatoxin accumulation and secondary traits. Two diallels among six local and exotic white and six yellow maize inbreds were evaluated at three locations in Texas. Inoculation with Aspergillus flavus Link:Fr. isolate NRRL 3357, either directly through the silk channel or as infested kernels on the soil surface, was effective in promoting AF accumulation in hybrids. White hybrids with low aflatoxin were CML269 X TxX24 and CML269 X CML176. CML269, CML176, and CML322 were the white inbreds with the lowest most consistent AF in hybrids and had the best GCA for aflatoxin resistance. Yellow hybrids with low AF were FR2128 X Mp715, Tx772 X Mp715, and Tx772 X CML326. Tx772 and FR2128 had the best GCA for reduced AF across locations or at specific locations. Inbreds CML326 and Tx772 had consistently low aflatoxin accumulation in hybrids across environments. AF content was correlated with husk cover, ear rot ratings, and insect damage. Exotic inbreds have genetic factors that can contribute to the reduction of aflatoxin contamination.

Betz, F. S., B. G. Hammond, et al. (2000). "Safety and Advantages of Bacillus thuringiensis-Protected Plants to Control Insect Pests." Regulatory Toxicology and Pharmacology 32(2): 156-173. http://www.sciencedirect.com/science/article/B6WPT-45BCPM3-M/2/4097b6db435328a57a60b2b6c1913376 AND http://www.botanischergarten.ch/Bt/Betz-Safety-Advantages-2000.pdf Plants modified to express insecticidal proteins from Bacillus thuringiensis (referred to as Bt-protected plants) provide a safe and highly effective method of insect control. Bt-protected corn, cotton, and potato were introduced into the United States in 1995/1996 and grown on a total of approximately 10 million acres in 1997, 20 million acres in 1998, and 29 million acres globally in 1999. The extremely rapid adoption of these Bt-protected crops demonstrates the outstanding grower satisfaction of the performance and value of these products. These crops provide highly effective control of major insect pests such as the European corn borer, southwestern corn borer, tobacco budworm, cotton bollworm, pink bollworm, and Colorado potato beetle and reduce reliance on conventional chemical pesticides. They have provided notably higher yields in cotton and corn. The estimated total net savings to the grower using Bt-protected cotton in the United States was approximately $92 million in 1998. Other benefits of these crops include reduced levels of the fungal toxin fumonisin in corn and the opportunity for supplemental pest control by beneficial insects due to the reduced use of broad-spectrum insecticides. Insect resistance management plans are being implemented to ensure the prolonged effectiveness of these products. Extensive testing of Bt-protected crops has been conducted which establishes the safety of these products to humans, animals, and the environment. Acute, subchronic, and chronic toxicology studies conducted over the past 40 years establish the safety of the microbial Bt products, including their expressed insecticidal (Cry) proteins, which are fully approved for marketing. Mammalian toxicology and digestive fate studies, which have been conducted with the proteins produced in the currently approved Bt-protected plant products, have confirmed that these Cry proteins are nontoxic to humans and pose no significant concern for allergenicity. Food and feed derived from Bt-protected crops which have been fully approved by regulatory agencies have been shown to be substantially equivalent to the food and feed derived from conventional crops. Nontarget organisms exposed to high levels of Cry protein are virtually unaffected, except for certain insects that are closely related to the target pests. Because the Cry protein is contained within the plant (in microgram quantities), the potential for exposure to farm workers and nontarget organisms is extremely low. The Cry proteins produced in Bt-protected crops have been shown to rapidly degrade when crop residue is incorporated into the soil. Thus the environmental impact of these crops is negligible. The human and environmental safety of Bt-protected crops is further supported by the long history of safe use for Bt microbial pesticides around the world.

Bezuidenhout, S. C., W. C. A. Gelderblom, et al. (1988). "Structure Elucidation of the Fumonisins, Mycotoxins from Fusarium-Moniliforme." Journal of the Chemical Society-Chemical Communications(11): 743-745. ://A1988N739100033

Bhandari, N. and R. P. Sharma (2002). "Modulation of selected cell signaling genes in mouse liver by fumonisin B-1." Chemico-Biological Interactions 139(3): 317-331. ://WOS:000174509000006 AND http://www.botanischergarten.ch/Bt/Bhandari-Modulation-Cell-signaling-2002.pdf Fumonisin B-1 (FB1) is a naturally occurring mycotoxin produced primarily by Fusarium verticilliodies and related fungi, common contaminants of corn throughout the world. FB1 is a carcinogen and causative agent of several lethal animal diseases, including equine leukoencephalomalacia and porcine pulmonary edema. Liver is the primary target organ in mice. In vivo and vitro, cells exposed to FB1 undergo a mixture of necrotic and apoptotic cell death. Our previous studies showed gender differences in hepatotoxicity caused after 5 day FB1 treatment. Gene alterations in cytokine network and apoptosis signaling molecules were also observed after an acute single dose of FB1. To further investigate the gene alterations after a subchronic FB1 exposure and its correlation to observed gender differences, male and female BALB/c mice (five per group) were injected subcutaneously with either saline or 2.25 mg/kg per day of FB1 for 5 days. FB1 caused increased expression of tumor necrosis factor alpha (TNFalpha), interleukin IL-1alpha IL-1beta, IL-1 receptor antagonist (IL-1Ra), IL-6, IL-10, IL-12 p40 IL-18 and interferon gamma (IFNgamma) in male liver. with a similar increase in females except for IL-1beta and IL-18. Control females showed higher basal levels of IL-1alpha, IL-1Ra, IL-10, IL-12 p40 and IFNgamma compared with males. Expression of TNF receptor 55 and TNF receptor associated death domain (TRADD) was increased, with no changes in Fas signaling molecules, Fits, Fas ligand (FasL), Fas associated death domain (FADD) and Fas-associated protein factor (FAF). Expression of oncogenic transcription factors, c-Myc, B-Myc, Max and Mad, and apoptotic genes, namely Bcl-22, Bax and Bad, was increased after FB1 treatment. FB1 caused an activation of cytokine network in liver, particularly the TNFalpha signaling pathway, suggesting its involvement in hepatotoxic mechanisms. Induction of IL-IRa and oncogenes is a likely mechanism for the cancer promoting properties of FB1 through a mechanism involving apoptotic necrosis, oncotic necrosis and consequent regeneration. (C) 2002 Elsevier Science Ireland Ltd. All rights reserved.

Bhatnagar, D., J. W. Cary, et al. (1998). "Molecular characterization of an aflatoxin B-2 producing mutant strain of Aspergillus flavus." Faseb Journal 12(8): 938. ://000083961501092

Bhatnagar, D., T. Cleveland, et al. (1995). "Molecular biology to eliminate aflatoxins." INFORM 6: 262-271. http://www.informinc.org/indcontribute.php not available: 1995

Bhatnagar, D. and T. E. Cleveland (1988). "Fate of the Methyl-Group During the Conversion of Sterigmatocystin into O-Methylsterigmatocystin and Aflatoxin-B1 by Cell-Free Preparations of Aspergillus-Parasiticus." Biochimie 70(6): 743-747. ://A1988P146800005

Bhatnagar, D. and T. E. Cleveland (1989). "Utilization of Purified Pertinent Fungal Enzymes for Development of Probes to Identify Genes Responsible for Aflatoxin Biosynthesis." Journal of Toxicology-Toxin Reviews 8(1-2): 305-318. ://A1989DA91700029

Bhatnagar, D. and T. E. Cleveland (1992). "Possible Regulatory Role of Camp in Aflatoxin Biosynthesis." Faseb Journal 6(1): A228-A228. ://A1992GY44001307

Bhatnagar, D., T. E. Cleveland, et al. (1991). "Enzymological Evidence for Separate Pathways for Aflatoxin-B1 and Aflatoxin-B2 Biosynthesis." Biochemistry 30(17): 4343-4350. ://A1991FK23400033 Aflatoxins B1 (AFB1) and B2 (AFB2) are biologically active secondary metabolites of Aspergillus flavus and Aspergillus parasiticus. These toxins are synthesized by the fungi from pathway precursors: sterigmatocystin (ST) --> O- methylsterigmatocystin (OMST) --> AFB1; dihydrosterigmatocystin (DHST) --> dihydro-O-methylsterigmatocystin (DHOMST) --> AFB2. The late stages of AFB1 synthesis are carried out by two enzyme activities, a methyltransferase (MT) (ST --> OMST), and an oxidoreductase (OR) (OMST --> AFB1). Properties of the purified MT have been identified in a previous investigation [Bhatnagar et al. (1988) Prep. Biochem. 18, 321]. In the current study, the OR was partially purified (150-fold of specific activity) from fungal cell-free extracts and characterized with extended investigation of the late stages of AFB1 and AFB2 synthesis. Whole cells of an isolate of A. flavus (SRRC 141), which produce only AFB2, were able to produce AFB1 in ST and OMST feeding studies; the results suggested that the enzymes involved in AFB2 biosynthesis also carry out AFB1 synthesis. Substrate competition experiments carried out with the OR showed that an increasing concentration of either OMST or DHOMST in the presence of a fixed, nonsaturating concentration of either DHOMST or OMST, respectively, resulted in a decline in production of one aflatoxin (B1 or B2) with a corresponding increase in the synthesis of the other toxin (B2 or B1). OMST was a preferred substrate (K(m), 1.2-mu-M) for the oxidoreductase as compared to DHOMST (K(m), 13.4-mu-M). Similar, substrate competition experiments showed that ST (K(m), 2.0-mu-M) was a preferred substrate over DHST (K(m), 22.5-mu-M) for a homogeneous MT. The results suggest that AFB1 and AFB2 synthesis is catalyzed by common enzymes that use separate precursors as substrates for the synthesis of each toxin. A biosynthetic grid for the AFB1 and AFB2 synthesis is presented on the basis of enzyme substrate specificity studies and cellular conversions of pertinent metabolites.

Bhatnagar, D., T. E. Cleveland, et al. (1989). "Comparison of the Enzymatic Composition of Cell-Free-Extracts of Non-Aflatoxigenic Aspergillus- Parasiticus with Respect to Late Stages of Aflatoxin Biosynthesis." Archives of Environmental Contamination and Toxicology 18(3): 434-438. ://A1989T676500019

Bhatnagar, D., T. E. Cleveland, et al. (1989). "Enzymes in Aflatoxin-B1 Biosynthesis - Strategies for Identifying Pertinent Genes." Mycopathologia 107(2-3): 75-83. ://A1989CB27000003

Bhatnagar, D., T. E. Cleveland, et al. (1987). "Elucidation of Aflatoxin Biosynthesis Using Aspergillus- Parasiticus Mutants." Journal of the American Oil Chemists Society 64(5): 626-626. ://A1987H286000030

Bhatnagar, D., P. J. Cotty, et al. (1992). "Preharvest Aflatoxin Contamination - Molecular Strategies for Its Control." Abstracts of Papers of the American Chemical Society 203: 93-AGFD. ://A1992HK16100093

Bhatnagar, D., P. J. Cotty, et al. (1993). "Preharvest Aflatoxin Contamination - Molecular Strategies for Its Control." Acs Symposium Series 528: 272-292. ://A1993LK20500024 Aflatoxins are carcinogens produced by Aspergillus flavus and A. parasiticus when these fungi infect crops before and after harvest, thereby contaminating food and feed and threatening both human and animal health. Traditional control methods (such as the use of certain cultural practices, pesticides and resistant varieties), which effectively reduce populations of many plant pests in the field, have not been effective in controlling aflatoxin-producing fungi. Our research, therefore, consists of acquiring knowledge of. 1) the molecular regulation of aflatoxin formation within the fungus, 2) environmental factors and biocompetitive microbes influencing growth of A. flavus and aflatoxin synthesis in crops, and 3) enhancement of host plant resistance to aflatoxin accumulation through understanding the biochemistry of host plant resistance responses. This understanding is expected to lead to development of biocontrol strategies and/or, in longer term research, development of elite crop lines ''immune'' to aflatoxin producing fungi.

Bhatnagar, D., K. C. Ehrlich, et al. (1993). "Biochemical-Characterization of an Aflatoxin-B(2) Producing Mutant of Aspergillus-Flavus." Faseb Journal 7(7): A1234-A1234. ://A1993KY84801139

Bhatnagar, D., K. C. Ehrlich, et al. (2003). "Molecular genetic analysis and regulation of aflatoxin biosynthesis." Applied Microbiology and Biotechnology 61(2): 83-93. ://000182702800001 Aflatoxins, produced by some Aspergillus species, are toxic and extremely carcinogenic furanocoumarins. Recent investigations of the molecular mechanism of AFB biosynthesis showed that the genes required for biosynthesis are in a 70 kb gene cluster. They encode a DNA-binding protein functioning in aflatoxin pathway gene regulation, and other enzymes such as cytochrome P450-type monooxygenases, dehydrogenases, methyltransferases, and polyketide and fatty acid synthases. Information gained from these studies has led to a better understanding of aflatoxin biosynthesis by these fungi. The characterization of genes involved in aflatoxin formation affords the opportunity to examine the mechanism of molecular regulation of the aflatoxin biosynthetic pathway, particularly during the interaction between aflatoxin-producing fungi and plants.

Bhatnagar, D., A. R. Lax, et al. (1996). "Purification of a 43 KDa enzyme that catalyzes the reduction of norsolorinic acid to averantin in aflatoxin biosynthesis." Faseb Journal 10(6): 3012-3012. ://A1996UK86103241

Bhatnagar, D. and S. P. McCormick (1987). "The Inhibitory Effect of Neem (Azadiracnta-Indica) Leaf Formulations on Aflatoxin Synthesis in Aspergillus-Parasiticus." Journal of the American Oil Chemists Society 64(5): 654-654. ://A1987H286000161

Bhatnagar, D. and S. P. McCormick (1988). "The Inhibitory Effect of Neem (Azadirachta-Indica) Leaf Extracts on Aflatoxin Synthesis in Aspergillus-Parasiticus." Journal of the American Oil Chemists Society 65(7): 1166-1168. ://A1988P219600019

Bhatnagar, D., S. P. McCormick, et al. (1986). "Identification and Placement of Averufanin as a Precursor in the Biosynthesis of Aflatoxin-B1." Phytopathology 76(10): 1144-1144. ://A1986F034600689

Bhatnagar, D., S. P. McCormick, et al. (1987). "Identification of O-Methylsterigmatocystin as an Aflatoxin-B1 and Aflatoxin-G1 Precursor in Aspergillus-Parasiticus." Applied and Environmental Microbiology 53(5): 1028-1033. ://A1987H185200021

Bhatnagar, D., A. H. Ullah, et al. (1987). "Purification and Characterization of a Methyltransferase Involved in the Latter Stages of the Aflatoxin Biosynthetic- Pathway." Federation Proceedings 46(6): 2290-2290. ://A1987H178702117

Bhatnagar, D., A. H. J. Ullah, et al. (1988). "Purification and Characterization of a Methyltransferase from Aspergillus-Parasiticus Srrc-163 Involved in Aflatoxin Biosynthetic-Pathway." Preparative Biochemistry 18(3): 321-349. ://A1988R034400007

Bhatnagar, D., J. J. Yu, et al. (2002). Toxins of filamentous fungi. Fungal Allergy and Pathogenicity. Basel, KARGER. 81: 167-206. ://000176962600010

Bhatnagar, S., F. J. Betran, et al. (2003). "Agronomic performance, aflatoxin accumulation and protein quality of subtropical and tropical QPM hybrids in southern US." Maydica 48(2): 113-124. ://000185935000004 Development and adoption of Quality Protein Maize (QPM), at homozygous (o(2)o(2)) hard endosperm high lysine corn, would increase the nutritional value of food and feed maize products. Elite white and yellow QPM hybrids with subtropical and tropical adaptation that are competitive ill yield with commercial checks have been developed. The objectives of this study were: i. to evaluate the adaptation and agronomic performance of tropical and subtropical white and yellow QPM hybrids in southern U.S. environments; ii. to assess their response to aflatoxin accumulation; and iii. to estimate their protein and lysine content. QPM hybrids and non-QPM commercial hybrids adapted to southern USA were evaluated in replicated trials at 6 (white) and 8 (yellow) environments, and in 2 inoculated trials with Aspergillus flavus. QPM hybrids had bigger tassels, higher ear placements and longer flowering dates than non-QPM checks. QPM hybrids yielded less than non- QPM checks across locations. Avenge yield across locations for white QPM hybrids was 5.54 t ha(-1) vs. 6.44 t ha(-1) for white non-QPM checks. Sonic white QPM hybrids had similar grain yields to commercial hybrids. For yellow QPM hybrids, the average yield was 5.55 t ha(-1) as compared to 7.44 t ha(-1) For non- QPM checks. Both white and yellow QPM hybrids were significantly less susceptible to aflatoxin than non-QPM checks. All QPM hybrids had superior nutritional quality. White QPM hybrids had average lysine per protein content of 41.73 g kg(-1) vs. 34.13 g kg(- 1) for commercial checks, and yellow QPM hybrids 41.91 g kg(-1) vs. 29.71 g k(-1) for non-QPM hybrids. Some QPM hybrids combined protein content similar to normal maize and high protein quality. QPM germplasm appears to be a source of aflatoxin resistance and nutritional quality. Although the agronomic performance of tropical and subtropical QPM hybrids was inferior to current commercial hybrids adapted to the area, it seems feasible to develop competitive QPM temperate hybrids with enhanced quality and nutritional value.

Blackwell, B. A., O. E. Edwards, et al. (1995). "Relative Configuration of the C-10 to C-16 Fragment of Fumonisin-B." Tetrahedron Letters 36(12): 1973-1976. ://A1995QP02000001 The relative stereochemistry of the C-10 to C-16 fragment of fumonisin B-1 has been deduced through NMR studies of the parent compound and comparison to the configuration found for a 10, 14-cyclic ether derivative of the FB1 aminopentaol (3). It is shown that the substituents at C-14 and C-15 are erythro, that those at C-14 and C-10 have the opposite relative configuration and that the methyl substituents at C-12 and C-16 have the same configuration as the hydroxyl at C-14.

Blackwell, B. A., O. E. Edwards, et al. (1995). "Nmr Structural Studies of Fumonisin-B1 and Related-Compounds from Fusarium-Moniliforme." Abstracts of Papers of the American Chemical Society 209: 97-AGFD. ://A1995QP23200097

Blackwell, B. A., J. T. Gilliam, et al. (1999). "Oxidative deamination of hydrolyzed fumonisin B-1 (AP(1)) by cultures of Exophiala spinifera." Natural Toxins 7(1): 31-38. ://000083573600003 and http://www.botanischergarten.ch/Mycotoxins/Blackwell-Deamination-Fumonisin-1999.pdf Fumonisins are mycotoxins of world-wide distribution in maize infected by the fungus Fusarium verticillioides. They are highly toxic to certain livestock and are potential carcinogens. Exophiala spinifera, a black yeast fungus found on moldy maize kernels, was identified previously as capable of growing on fumonisin B1 as a sole carbon source and thus is a potential source for fumonisin detoxifying enzymes. Pure cultures of E. spinifera transform fumonisin B-1 to the amino polyol AP(1) plus free tricarballylic acid through the activity of a soluble extracellular esterase, and further transformation is evidenced by accumulation in culture supernatant of a less polar compound(s) lacking a fluorescamine-reactive amino group. A free amine is thought to be critical for biological activity of FB1 or AP(1). As a first step towards characterizing this amine-modifying activity, we investigated the biotransformation of AP(1) by E. spinifera liquid cultures that had been previously grown in liquid medium containing AP(1) as a sole carbon source. Accumulation of AP(1)-derived metabolites was monitored by thin-layer chromatography of culture supernatants, and product metabolites were purified and evaluated by mass spectrometry and nuclear magnetic resonance. Two products of treatment of purified AP(1) with cultures of E. spinifera are shown to be N-acetyl AP(1) and a new compound, 2-oxo-12,16- dimethyl-3,5,10,14,15-icosanepentol hemiketal (or 2-OP1 hemiketal). Copyright (C) 1999 John Wiley & Sons, Ltd.

Blackwell, B. A., J. D. Miller, et al. (1994). "Production of Carbon 14-Labeled Fumonisin in Liquid Culture." Journal of Aoac International 77(2): 506-511. ://A1994NF07800034 A method for the production and purification of radiolabeled fumonisin that involves the addition of C-14-acetate to liquid cultures of Fusarium moniliforme in shake flasks is reported. Stable isotope C-13 labeling studies were carried out using specifically enriched acetate and several amino acids to determine the location of labeled carbon atoms in the radiolabeled fumonisin that was also produced (650 mu Ci/mmol). These experiments determined that the C-14 was distributed throughout the molecule making it useful for studies of fumonisin residues in animal products. Additionally, the C-13 studies indicated that the biosynthesis of fumonisin involves the addition of methionine, glutarate, and serine or alanine to the hydrocarbon backbone. These data best fit the hypothesis that this back bone is polyketide in origin as opposed to being a modified lipid.

Blandino, M., M. A. Saladini, et al. (2008). "THE INFLUENCE OF SOWING DATE AND INSECTICIDE TREATMENTS ON OSTRINIA NUBILALIS (HUBNER) DAMAGE AND FUMONISIN CONTAMINATION IN MAIZE KERNELS." Maydica 53(3-4): 199-206. ://WOS:000267398000005 Fusarium verticillioides, a known producer of fumonisins, has been reported to be the most common pathogen of maize Causing Fusarium ear rot and grain fumonism contamination. A field experiment was conducted from 2005 to 2007 in North Italy to determine the effects of sowing date and insecticide treatment against ECB on the Susceptibility of maize to Fusarium ear rot and to fumonisin contamination in natural infection conditions. Three sowing dates and two insecticide applications were compared for each year. The late sown maize showed significantly higher insect damage to both the plants (stalks) and the ears (kernels and cobs). The ECB damage severity was 23% higher for the later sowing date than for the earlier. The insecticide treatment significantly reduced the ECB infestation compared to the untreated control. A significant effect of the sowing date and of the insecticide application on Fusarium ear rot was highlighted. The earlier sowing date reduced the ear rot incidence and severity by 25% and 49%, respectively, compared to the later dates. The insecticide application led to 25% lower ear rot severity than the untreated control. The fumonisin contamination was significantly reduced by an earlier sowing date (62%) and by the treatment against ECB (51%). The plots sown earlier and treated with insecticide resulted in a 79% lower concentration of fumonisins in kernels compared to plots characterized by later sowing and a lack of treatment. In fuperate climates, where ECB attack is consistent,I low fumonisin contamination may be enhanced by an early sowing date and a correct insecticide application against 2nd-generation ECB larvae.

Blaney, B. J. and K. C. Williams (1991). "Effective Use in Livestock Feeds of Moldy and Weather-Damaged Grain Containing Mycotoxins - Case- Histories and Economic Assessments Pertaining to Pig and Poultry Industries of Queensland." Australian Journal of Agricultural Research 42(6): 993-1012. ://A1991GB55000005

Blesa, J., G. Meca, et al. (2010). "Glucose influence on the production of T-2 toxin by Fusarium sporotrichioides." Toxicon 55(6): 1157-1161. ://WOS:000276436600014 Toxigenic isolate of Fusarium sporotrichioides was tested for the 1-2 toxin production on PDA plates during 10 days under various glucose concentrations. 1-2 toxin was determined by LC-MS and confirmed with LC-MS/MS. This analytical method has been applied, for the first time, to an extensive study of 1-2 accumulation. Results showed that the production of this mycotoxin is directly correlated to the concentration of glucose present in the medium. Concentrations of T-2 toxin produced by the strain of F. sporotrichioides ranged from 0 to 1.45 mg/kg. The better 1-2 production was evidenced in the fermentation operated with 20% of glucose. (C) 2010 Elsevier Ltd. All rights reserved.

Borgemeister, C., C. Adda, et al. (1998). "Timing of harvest in maize: effects on post harvest losses due to insects and fungi in central Benin, with particular reference to Prostephanus truncatus (Horn) (Coleoptera : Bostrichidae)." Agriculture Ecosystems & Environment 69(3): 233-242. ://000074584600005 A storage experiment was conducted in Bante, central Benin between autumn 1994 and spring 1995. The maize was harvested 1, 3, and 7 weeks after physiological maturity and stored for up to eight months. The main results were: (a) Leaving the maize in the field for extended periods after physiological maturity resulted in severe grain losses after eight months of storage; (b) Most of the grain losses were attributed to Prostephanus truncatus; (c) Early harvested maize had a higher proportion of mouldy grain; (d) Harvest date had no consistent effect on the level of aflatoxin contamination; (e) Based on a participatory evaluation of maize quality by local farmers, the economic value of maize stored for eight months was highest in maize harvested three weeks after physiological maturity. (C) 1998 Elsevier Science B.V. All rights reserved.

Bouhet, S., E. Hourcade, et al. (2004). "The mycotoxin fumonisin B-1 alters the proliferation and the barrier function of porcine intestinal epithelial cells." Toxicological Sciences 77(1): 165-171. ://000187988800021 Fumonisin B-1 (FB1) is a mycotoxin produced by Fusarium verticillioides (formerly F. moniliforme), a fungus that commonly contaminates maize. FB1 causes toxicological effects in laboratory and domestic animals including pigs. Because the gastrointestinal tract represents the first barrier met by exogenous food compounds, the purpose of this study was to investigate the effects of FB1 on IPEC-1, a porcine intestinal epithelial cell line. We first verified that low concentrations of FB1 did not exert any cytotoxic effect on IPEC-1. Indeed, significant LDH release was only observed for FB1 concentrations greater than 50 and 700 muM on proliferating and nonproliferating cells, respectively. We then demonstrated that FB1 inhibits proliferation of IPEC-1. Fluorescence-activated cell sorting (FACS) analysis of the cell cycle indicated that FB1 blocks the proliferation of intestinal cells in the G0/G1 phase. Similar results were obtained with LLC-PK1, a renal porcine epithelial cell line, which is considered to be a good model for studying FB1 in vitro effects. We have also assessed the effects of FB1 on the integrity of the barrier formed by the intestinal epithelium. We demonstrated that FB1 decreases the transepithelial electrical resistance (TEER) of IPEC-1 in a time- and dose-dependent manner. This effect was only noticed after a long exposure (8-12 days of treatment). FB1 induced the TEER decrease independently of the cell differentiation stage, and this effect was partially reversible. Taken together, our data indicate that FB1 alters the proliferation and the barrier function of intestinal cells. These results may have implications for humans and animals consuming FB1-contaminated food or feed.

Bradshaw, R. E., D. Bhatnagar, et al. (2002). "Dothistroma pini, a forest pathogen, contains homologs of aflatoxin biosynthetic pathway genes." Applied and Environmental Microbiology 68(6): 2885-2892. ://000176030100034 Homologs of aflatoxin biosynthetic genes have been identified in the pine needle pathogen Dothistroma pini. D. pini produces dothistromin, a difuranoanthraquinone toxin with structural similarity to the aflatoxin precursor versicolorin B. Previous studies with purified dothistromin suggest a possible role for this toxin in pathogenicity. By using an aflatoxin gene as a hybridization probe, a genomic D. pini clone was identified that contained four dot genes with similarity to genes in aflatoxin and sterigmatocystin gene clusters with predicted activities of a ketoreductase (dotA), oxidase (dotB), major facilitator superfamily transporter (dotC), and thioesterase (dotD). A D. pini dotA mutant was made by targeted gene replacement and shown to be severely impaired in dothistromin production, confirming that dotA is involved in dothistromin biosynthesis. Accumulation of versicolorin A (a precursor of aflatoxin) by the dotA mutant confirms that the dotA gene product is involved in an aflatoxin-like biosynthetic pathway. Since toxin genes have been found to be clustered in fungi in every case analyzed so far, it is speculated that the four dot genes may comprise part of a dothistromin biosynthetic gene cluster. A fifth gene, ddhA, is not a homolog of aflatoxin genes and could be at one end of the dothistromin cluster. These genes will allow comparative biochemical and genetic studies of the aflatoxin and dothistromin biosynthetic pathways and may also lead to new ways to control Dothistroma needle blight.

Brera, C., F. Debegnach, et al. (2004). "Effect of industrial processing on the distribution of fumonisin B-1 in dry milling corn fractions." Journal of Food Protection 67(6): 1261-1266. ://000221897200030 The aim of this study was to investigate the distribution of fumonisin B, in various corn milling fractions processed by an industrial plant. Corn kernels and six derived milling fractions (germ, bran, large and small grits, animal feed flour, and flour) were sampled. In addition, in order to evaluate the effect of cooking, samples of polenta were prepared starting from naturally contaminated flour obtained from the industrial processing cycle. The industrial plant worked continuously at a rate of 60 tons per day. Two sublots of 5 tons each were investigated with samples of derived products taken at regular time intervals. Due to a similar heterogeneous distribution of fumonisin B-1 with other mycotoxins, such as aflatoxins, the sampling scheme was derived from the European Directive 98/53 for aflatoxins. Both lots of kernels showed fumonisin contamination at 4.54 and 5.09 mg/kg, respectively. Germ, bran, and animal feed flour showed contamination levels, namely 8.92 mg/kg (lot 1) and 9.56 mg/kg (lot 2), 7.08 mg/kg (lot 1) and 8.08 mg/kg (lot 2), and 9.36 mg/kg (lot 1) and 6.86 mg/kg (lot 2) higher than large and small grits and flour (0.39 mg/kg [lot 1] and 0.42 mg/kg [lot 2], 0.60 mg/kg [lot 1] and 1.01 mg/kg [lot 2], and 0.40 mg/kg [lot 1] and 0.45 mg/kg [lot 2], respectively). These results seem to account both for the industrial yields of the derived products and the distribution of fumonisin contamination in a kernel. The cooking of polenta in a domestic pressure cooker did not affect fumonism contamination because the mycotoxin concentrations were similar to those of the starting flour (0.40 and 0.45 mg/kg).

Brooks, T. D., W. P. Williams, et al. (2005). "Quantitative trait loci contributing resistance to aflatoxin accumulation in the maize inbred Mp313E." Crop Science 45(1): 171-174. ://WOS:000226435300021 Aflatoxin is a carcinogenic and toxic compound produced by the fungus Aspergillus flavus (Link:fr) that can be found at detrimentally high concentrations in maize (Zea mays L.) grain. Screening has led to the discovery of sources of resistance to aflatoxin accumulation in maize, but associated poor agronomic characteristics and complex inheritance have limited transfer of resistance to elite inbreds. A set of 210 F-2:3 families derived from a cross between inbred lines Mp313E (resistant) and B73 (susceptible) was evaluated in replicated trials in four environments for resistance to aflatoxin accumulation. Families were also genotyped using simple sequence repeat (SSR) markers to develop a genetic map for quantitative trait loci (QTL) analysis. Composite interval mapping (CIM) was used to identify 2, 3, 5, and 3 QTL within the tests at Stoneville (2000) and Mississippi State (2000, 2001, 2002), respectively. The QTL were primarily additive in nature, with Mp313E contributing to reduced aflatoxin concentration in all but one case. Two QTL regions were significant in at least three environments. The afl3 locus, represented by marker bnlg371, was located on chromosome two and accounted for 7 to 18% of variation in aflatoxin levels depending on environment. The afl5 locus, represented by marker bnlg2291, was located on chromosome four, with explained variance ranging from 8 to 18%. This QTL has been noted in earlier studies whereas afl3 is new. Identified QTL confirm important regions influencing aflatoxin accumulation previously identified and present new ones of equal effect.

Brown, M. P., C. S. Brown-Jenco, et al. (1999). "Genetic and molecular analysis of aflatoxin biosynthesis." Fungal Genetics and Biology 26(2): 81-98. ://000080253900001 and http://www.botanischergarten.ch/Mycotoxins/Brown-Rev-Aflatox-biosynth-1999.pdf The aflatoxin biosynthetic pathway represents one of the best studied pathways of fungal secondary metabolism. Its elucidation is the result of over 30 years of study by scientists in many disciplines. For recent reviews on the chemistry of the pathway see articles by Bhatnagar et al. (1992) Minto and Townsend (1997), and Woloshuk and Prieto (1997). Concern over the toxicity and carcinogenicity of aflatoxin has been the prime force driving research in this area. Aflatoxin B1 (AFB1) is the most potent naturally occurring carcinogen known (Squire, 1989), and epidemiological data implicate aflatoxin as a component of liver cancer in humans in certain parts of the world (Hall and Wild, 1994). Although aflatoxins are not extremely toxic, consumption of aflatoxin contaminated food by animals can lead to decreased weight gain, hemorrhaging, and suppression of the immune system (Miller andWilson, 1994).

Brown, R. L., C. S. Brown-Jenco, et al. (2003). "Construction and preliminary evaluation of an Aspergillus flavus reporter gene construct as a potential tool for screening aflatoxin resistance." Journal of Food Protection 66(10): 1927-1931. ://000185821500028 Effective preharvest strategies to eliminate aflatoxin accumulation in crops are not presently available. The molecular biology of aflatoxin biosynthesis has been extensively studied, and genetic and molecular tools such as reporter gene systems for the measurement of fungal growth have been developed. A reporter construct containing the Aspergillus flavus beta-tubulin gene promoter fused to Escherichia coli beta-glucuronidase (GUS) has been shown to be a reliable tool for the indirect measurement of fungal growth in maize kernels. Since cost-saving alternative methods for the direct measurement of aflatoxin levels are needed to facilitate more widespread field and laboratory screening of maize lines, a new reporter gene construct involving the promoter region of the omtA gene of the aflatoxin biosynthetic pathway was constructed and tested. Expression of GUS activity by this construct (omtA::GUS) was correlated with aflatoxin accumulation in culture. In the fungal transformant GAP26-1, which harbors this construct, aflatoxin production and GUS expression on sucrose- containing medium showed the same temporal pattern of toxin induction. Furthermore, GUS expression by GAP26-1 was shown to be associated with aflatoxin accumulation in maize kernels inoculated with this strain. Our results suggest that this and other reporter gene pathway promoter constructs may provide superior alternatives to direct aflatoxin quantification with respect to time, labor, and materials for the screening of maize lines for resistance to aflatoxin accumulation.

Brown, R. L., Z. Y. Chen, et al. (2001). "Resistance to aflatoxin accumulation in kernels of maize inbreds selected for ear rot resistance in West and Central Africa." Journal of Food Protection 64(3): 396-400. ://000167326800020 Thirty-six inbred hues selected in West and Central Africa for moderate to high resistance to maize ear rot under conditions of severe natural infection were screened for resistance to aflatoxin contamination using the previously established kernel screening assay. Results showed that more than half the inbreds accumulated aflatoxins at levels as low as or lower than the resistant U.S. Lines GT-MAS:gk or M182. In 10 selected aflatoxin-resistant or aflatoxin-susceptible inbreds, Aspergillus flavus growth, which was quantified using an A. flavus transformant containing a GUS-B-tubulin reporter gene construct, was, in general, positively related to aflatoxin accumulation. However, one aflatoxin-resistant inbred supported a relatively high level of fungal infection, whereas two susceptibles supported relatively low fungal infection. When kernels of the 10 tested lines were profiled for proteins using sodium dodecyl sulfate-polyacrylamide gel electrophoresis, significant variations from protein profiles of U.S. lines were observed. Confirmation of resistance in promising African lines in held trials may significantly broaden the resistant germplasm base available for managing aflatoxin contamination through breeding approaches. Biochemical resistance markers different from those being identified and characterized in U.S. genotypes, such as ones inhibitory to aflatoxin biosynthesis rather than to fungal infection, may also be identified in African lines. These discoveries could significantly enhance the host resistance strategy of pyramiding different traits into agronomically useful maize germplasm to control aflatoxin contamination.

Brown, R. L., T. E. Cleveland, et al. (1995). "Determination of Resistance to Aflatoxin Production in Maize Kernels and Detection of Fungal Colonization Using an Aspergillus-Flavus Transformant Expressing Escherichia-Coli Beta-Glucuronidase." Phytopathology 85(9): 983-989. ://A1995RY28900009

Brown, R. L., T. E. Cleveland, et al. (2001). "Growth inhibition of a Fusarium verticillioides GUS strain in corn kernels of aflatoxin-resistant genotypes." Applied Microbiology and Biotechnology 57(5-6): 708-711. ://000172959700018 Two corn genotypes, GT-MAS:gk and MI82, resistant to Aspergillus flavus infection/aflatoxin contamination, were tested for their ability to limit growth of Fusarium verticillioides. An F. verticillioides strain was transformed with a P-glucuronidase (GUS) reporter gene (uidA) construct to facilitate fungal growth quantification and then inoculated onto endosperm-wounded and non-wounded kernels of the above- corn lines. To serve as a control, an A. flavus strain containing the same reporter gene construct was inoculated onto non-wounded kernels of GT-MAS:gk. Results showed that, as in a previous study, non-wounded GT-MAS:gk kernels supported less growth (six- to ten-fold) of A. flavus than did kernels of a susceptible control. Also, non-wounded kernels of GT- MAS:gk and MI82 supported less growth (two- to four-fold) of F. verticillioides than did susceptible kernels. Wounding, however, increased F. verticillioides infection of MI82, but not that of GT-MAS:gk. This is in contrast to a previous study of A. flavus, where wounding increased infection of GT-MAS:gk rather than MI82 kernels. Further study is needed to explain genotypic variation in the kernel response to A. flavus and F. verticillioides kernel infections. Also, the potential for aflatoxin-resistant corn lines to likewise inhibit growth of F. verticillioides needs to be confirmed in the field.

Brown, R. W., A. C. Pier, et al. (1981). "Effects of Dietary Aflatoxin on Existing Bacterial Intra-Mammary Infections of Dairy-Cows." American Journal of Veterinary Research 42(6): 927-933. ://WOS:A1981LS98900005

Bruns, H. A. (2003). "Controlling aflatoxin and fumonisin in maize by crop management." Journal of Toxicology-Toxin Reviews 22(2-3): 153-173. ://000185165300003 Maize is a vital food and feed grain worldwide. Aflatoxin and fumonisin, mycotoxins produced primarily by the fungi Aspergillus flavus and Aspergillus parasiticus Speare, and Fusarium moniliforme J. Sheld, respectively, are very potent carcinogens in both humans and livestock and can readily contaminate maize grain in the field and in storage. Stress on developing maize, particularly during reproductive growth, facilitates infection by the fungi, production of mycotoxins and contamination of the grain. Drought, excessive heat, inadequate plant nutrition, insect feeding on developing kernels, weeds, excessive plant populations, and other plant diseases can produce plant stress and facilitate the infection of maize grain by mycotoxin producing fungi. Timely planting of adapted hybrids, proper plant nutrition, irrigation, and insect control either by insecticides or the use of transgenic hybrids all assist in curbing mycotoxin contamination. Production practices that produce high yields are basically the same ones that help control mycotoxins. Care must also be exercised in harvesting and handling grain in transport and storage to reduce kernel breakage and prevent contamination. Harvesting early and artificial drying helps reduce the incidence of mycotoxins as well as preventing kernel breakage and stored- grain insect infestations.

Bruns, H. A. and H. K. Abbas (2003). "Effects of plant populations on maize hybrids in the sub-tropical Mid South USA." Maydica 48(1): 21-27. ://000183623100004 Maize (Zea mays L.) production in the Mid South USA has increased in the past 15 years. Hybrids produced in the 1950's and 1960's responded to increased plant densities by producing more barren plants ha(-1) and less grain per plant. Hybrids grown today, by contrast, produce high grain yields under high plant Populations. Maize production in the Mid South often uses a 101.6 cm row spacing, which is commonly used to produce cotton (Gossypium birsutum L.). Six maize hybrids, two Bt and four normal, were grown using a 101.6 cut row spacing and plant densities of 43,000, 48,000, 54,300, 64,000 and 76,500 plants ha(-1) in 2000 and 2001 at Stoneville, MS. Data on yield, grain bulk density, kernel weight, ear weight, leaf area plant(-1), LAI and mycotoxin concentrations were analyzed. Yields increased with increasing plant density with no yield plateau or decline observed at the highest population. Grain bulk densities varied among plant densities but no trend was evident. Kernel weights, ear weights, and leaf area plant-1 all declined with increasing plant density. However, declines in kernel and ear weights did not adversely affect grain yield. Ears ha-1 was the most important yield component in this experiment. Leaf area index increased with increasing plant density thus negating the decline in leaf area plant(-1). Leaf area index was higher in 2000 than in 2001, probably due to more rainfall. Hybrids differed in LAI, yield, kernel bulk density and kernel weight but, these differences were not correlated to each other. Aflatoxin levels were below the maximum allowable level of 30 mg Mg-1 both years of the experiment. Fumonisin levels were higher in 2001 (5-0-7.9 mg kg(-1)) than in 2000 (0.5-1.6 mg kg(-1)) due to a more favorable environment for its production. Maize can be grown in the Mid South USA using the currently available hybrids and a Population of 76,500 plants ha(-1) without a decline in yield or grain quality.

Bruns, H. A. and H. K. Abbas (2004). "Effects of harvest date on maize in the humid sub-tropical mid-south USA." Maydica 49(1): 1-7. ://000222736300001 Limited capacity for artificially drying maize (Zea mays L.) grain exists in the mid-south USA. Most of the area's production is field- dried and thus subjected to risks inherent to leaving mature crops in the field. A two-year experiment to assess some of the effects of delayed harvest on maize grain yield and other characteristics was conducted at Stoneville, MS. Six maize hybrids (three Bt and three non-Bt) were field grown in 2000 and 2001. Grain was hand harvested and shelled at 14, 28, 42 56, and 70 d post-physiological maturity (P-PM). Grain moisture levels declined with increased delays in harvest both years. Levels safe for handling and storage (150 mg g(-1)) were acquired at 28 cl P-PM in 2000 and 42 d P-PM in 2001. Grain moisture fell below 120 mg g(-1), 28 d P-PM in 2000 making it subject to mechanical damage. Declines in grain bulk density at 70 cl P-PM may he explained by such damage. Bt hybrids had less stalk lodging than non-Bt hybrids, and lodging tended to increase as hat-vests were delayed. Aflatoxin contamination Was minimal in 2000 and non-existent in 2001. Fumionisin levels were higher in 2001 than 2000. Adverse effects on yield and grain quality With delayed harvest appear minimal, inherent risks Of crop losses due to weather exist though, and monitoring grain moisture and the weather are recommended.

Bruns, H. A. and H. K. Abbas (2006). "Planting date effects on Bt and non-Bt corn in the Mid-South USA." Agronomy Journal 98(1): 100-106. ://WOS:000235108100013 Corn (Zea mays L.) planting dates are regional and vary across the contiguous USA. Improved technologies allow corn to be planted earlier. The objective of this research was to evaluate the effects of planting date on the agronomics of Bt and non-Bt hybrids grown in the Mid-South. Twelve hybrids, two Bt [Bacillus thuringiensis (Berliner)], and two non-Bt for three maturity groups [short-season (1180-1270 GDU 10's), mid-season (1445-1470 GDU 10's), and full-season (15401625 GDU 10's)] were evaluated for GDU 10's at silking and physiological maturity, yield, yield components, and mycotoxins in 2002, 2003, and 2004 at Stoneville, MS. Plots were planted in a split-plot of a randomized complete block replicated four times and furrow irrigated. Whole plots were plantings in early April, late April, or mid-May, while subplots were hybrids randomly assigned. Experimental units were four 102-cm rows, 9.1 in long. Lodging and dropped ears were incon- sequential. Yields were greater for both April plantings (8.6 and 9.2 Mg ha(-1) for early April and late April, respectively) than mid-May plantings (7.8 Mg ha(-1)). Short-season hybrids generally yielded less than mid-season or full-season hybrids. The Bt hybrids yielded more than non-Bt hybrids (9.1 Mg ha(-1) vs. 7.9 Mg ha(-1), respectively). Yields correlated with GDU 10's at silking [yield = 0.037x - 20.416 (r = 0.77)] but not physiological maturity. Aflatoxin was high in 2002 (224.0 mg Mg- 1), and much less (28.8 and 7.4 ing Mg-1) in 2003 and 2004, respectively. The Bt hybrids had less fumonisin contamination than non- Bt hybrids (5.2 mg kg(-1) vs. 8.5 mg kg(-1)) but less aflatoxin only in 2003 (12.4 ing Mg-1 vs. 45.3 mg Mg-1).

Buntin, G. D., J. N. All, et al. (2004). "Plant-incorporated Bacillus thuringiensis resistance for control of fall armyworm and corn earworm (Lepidoptera : Noctuidae) in corn." Journal of Economic Entomology 97(5): 1603-1611. ://000224653200016 Fall armyworm, Spodoptera frugiperda (JE. Smith), and corn earworm, Helicoverpa zea (Boddie), perennially cause leaf and ear damage to corn, Zea mays L., in the southeastern United States. Transgenic Bacillus thuringiensis (Bt) hybrids with the Bt11, MON810, or 176 events expressing the Cry1Ab insecticidal endotoxin from were evaluated for control fall armyworm and corn earworm, at seven locations in Georgia during 1999 and 2000. Corn was planted at the recommended time for each location and 1 and 2 mo later in the southern locations. All Bt events consistently reduced whorl infestation and damage, although event 176 did not prevent whorl damage in the later plantings in the southern locations in both years. All events also reduced seedling damage by the lesser cornstalk borer, Elasmopalpus lignosellus (Zeller), in one trial and stalk infestations and tunnel length by southwestern corn borers, Diatraea grandiosella Dyar, in another trial. Hybrids containing Bt11 and MON810 events reduced ear infestations in all trials, although reductions were small in later plantings. Nevertheless, both events reduced grain damage from earworms and armyworms by an average +/- SE of 52.5 +/- 5.1% in all trials. The hybrid containing event 176 did not reduce ear infestations and damage. Total grain aflatoxin concentrations were not significantly affected by Bt resistance in any trial (N = 17). Yield responses were variable with the prevention of yield loss being proportional to the severity of insect damage. Although plantings made after the recommended time did not consistently benefit from Bt resistance, Bt11 and MON810 events were effective in reducing damage to field corn when large infestations occurred. The Bt11 and MON810 events mitigated the risk of severe lepidopteran damage to corn, thereby making later plantings of corn feasible in double-cropping systems.

Buntin, G. D., R. D. Lee, et al. (2001). "Evaluation of yieldgard transgenic resistance for control of fall armyworm and corn earworm (Lepidoptera : Noctuidae) on corn." Florida Entomologist 84(1): 37-42. ://000168101100005 Fall armyworm, Spodoptera frugiperda (J. E. Smith), and corn earworm, Helicoverpa tea Boddie, perennially cause leaf and ear damage to corn in the southeastern USA. Development of transgenic hybrids expressing insecticidal endotoxin from Bacillus thuringiensis (Bt) offers a new approach to managing these insects in field corn. Transgenic Pt hybrids with either the Bt11 or MON810 event, collectively known as YieldGard Technology, were evaluated for control fall armyworm and corn earworm in southern Georgia during 1998, which coincided with a severe outbreak of fall armyworm. YieldGard Pt resistance consistently reduced whorl infestation and damage to low levels and also reduced ear infestations and larval numbers per ear. However, larval establishment did occur on many ears of resistant plants, but once established in ears, larvae of both species developed more slowly and caused much less kernel damage on resistant than susceptible plants. We found no relationship between YieldGard Bt resistance and corn grain aflatoxin concentrations. Yield responses were variable with the prevention of yield loss being proportional to the severity of insect damage. These results indicate that YieldGard resistance is effective in preventing significant losses to field corn by fall armyworm and corn earworm. Further, evaluation under a variety of growing conditions and insect infestation levels is needed to clearly assess the value of YieldGard technology to corn growers in the Southeast.

Burow, G. B., H. W. Gardner, et al. (2000). "A peanut seed lipoxygenase responsive to Aspergillus colonization." Plant Molecular Biology 42(5): 689-701. ://000086411400003 Several lines of evidence have indicated that lipoxygenase enzymes (LOX) and their products, especially 9S- and 13S- hydroperoxy fatty acids, could play a role in the Aspergillus/seed interaction. Both hydroperoxides exhibit sporogenic effects on Aspergillus spp. (Calvo, A., Hinze, L., Gardner, H.W. and Keller, N.P. 1999. Appl. Environ. Microbiol. 65: 3668-3673) and differentially modulate aflatoxin pathway gene transcription (Burow, G.B., Nesbitt, T.C., Dunlap, J. and Keller, N.P. 1997. Mol. Plant-Microbe Interact. 10: 380-387). To examine the role of seed LOXs at the molecular level, a peanut (Arachis hypogaea L.) seed gene, PnLOX1, was cloned and characterized. Analysis of nucleotide sequence suggests that PnLOX1 encodes a predicted 98 kDa protein highly similar in sequence and biochemical properties to soybean LOX2. The full- length PnLOX1 cDNA was subcloned into an expression vector to determine the type(s) of hydroperoxide products the enzyme produces. Analysis of the oxidation products of PnLOX1 revealed that it produced a mixture of 30% 9S-HPODE (9S-hydroperoxy-10E, 12Z-octadecadienoic acid) and 70% 13S-HPODE (13S-hydroperoxy- 9Z, 11E-octadecadienoic acid) at pH 7. PnLOX1 is an organ- specific gene which is constitutively expressed in immature cotyledons but is highly induced by methyl jasmonate, wounding and Aspergillus infections in mature cotyledons. Examination of HPODE production in infected cotyledons suggests PnLOX1 expression may lead to an increase in 9S-HPODE in the seed.

Bush, B. J., M. L. Carson, et al. (2004). "Infection and fumonisin production by Fusarium verticillioides in developing maize kernels." Phytopathology 94(1): 88-93. ://000220532100009 Fusarium ear rot and fumonisin contamination are serious problems for maize growers, particularly in the southeastern United States. The lack of maize genotypes highly resistant to infection by Fusarium verticillioides or to fumonisin contamination emphasizes the need for management strategies to prevent contamination by this mycotoxin. Information on the initial appearance of infection and fumonisin contamination of kernels and their increase over time is needed to determine if early harvest may be an appropriate control strategy. Maize ears from replicated studies at two locations in eastern North Carolina were harvested weekly, starting 2 weeks after pollination and continuing for 14 weeks. The percentage of kernels infected with E verticillioides and the fumonisin contamination in the harvested samples were determined. Kernel infection by F. verticillioides and fumonisin contamination appeared as kernels neared physiological maturity and increased up to the average harvest date for maize in North Carolina. Beyond this date, the concentrations of fumonisin fluctuated. Under years conducive for fumonisin contamination. early harvest (greater than 25% grain moisture) may help reduce the level of contamination.

Butron, A., R. G. Li, et al. (2001). "Molecular markers to increase corn earworm resistance in a maize population." Maydica 46(2): 117-124. ://000170645200007 Maysin and related compounds, such as apimaysin, 3 ' - methoxymaysin, and chlorogenic acid, have been determined to be important maize (Zea mays L.) produced antibiotic compounds against corn earworm (Helicoverpa zea Boddie), but, to be effective under field conditions, silk antibiotics should be accompanied by good husk coverage. The objective of this work was to identify molecular markers associated with synthesis of maysin and related compounds in a maize Population and determine if the markers could be linked to the genes which affect husk tightness. A total of 113 probes were used to screen for RFLP polymorphisms and the 53 probes that were polymorphic between the parents were used as codominant markers to genotype 205 F-2 individuals. Silks and husks of F-2:3 families were evaluated. Two major QTL were identified for the synthesis of maysin and related compounds, the already known pl, on the short arm of chromosome 1, and a novel one on the interval csu1066-umcl76 on genomic region 2C-2L. A QTL for husk tightness was located near pl. The functional allele for pi and the favorable allele for husk tightness were in repulsion linkage. in a marker-assisted selection program for increasing resistance to corn earworm, markers for silk antibiotic synthesis should be accompanied by markers for husk tightness. Efforts Should be made to convert the RFLP-markers into PCR- based markers for user friendly application in marker-assisted breeding.

Cahagnier, B., D. Melcion, et al. (1995). "Growth of Fusarium-Moniliforme and Its Biosynthesis of Fumonisin B1 on Maize Grain as a Function of Different Water Activities." Letters in Applied Microbiology 20(4): 247-251. ://WOS:A1995QV42900014

Caldas, E. D., S. C. Silva, et al. (2002). "Aflatoxins and ochratoxin A in food and the risks to human health." Revista De Saude Publica 36(3): 319- 323. ://000177436900010 AND http://www.botanischergarten.ch/Bt/Caldas-Aflaxoxinas-Ocratoxina-2002.pdf Objectives The presence of mycotoxins in food has been associated with several human diseases, and health authorities have taken actions to decrease the ingestion of these compounds in the diet. A study was carried out to assess aflatoxins and ochratoxin A concentrations found in food, and to evaluate the potential risk to human health resulting from mycotoxin exposure. Methods Between July 1998 to December 2001, 366 food samples were analyzed, including peanuts and its products, nuts, maize, oat and/or Wheat products, rice and beans. Samples were processed and the extracted mycotoxins were detected and separated using thin layer chromatography, and then quantified with fluorescence. Results Aflatoxins were detected in 19.6% of the samples: raw peanuts and its products, pop corn, maize and Brazilian nuts (>2mg/kg). Peanuts and its products showed the highest levels of aflatoxin contamination (34.7%) with up to 1280mg/kg of AFBI + AFGI and 1706 mg/kg of total aflatoxins. Of the Positive samples. AFBI was detected in 98.5%, AFB2 in 93%. AFGI in 66.7%, and AFG2 in 65.4%. Ochratoxin A was not detected (<25 mg/kg) in any sample analyzed. Conclusion It was found that contamination levels mainly seen in peanuts and its products exceed Brazilian regulated standards, and they can be a potential risk to regular consumers of these products. Food producers' awareness allied to monitoring programs is essential to reduce bunion exposure to these compounds and prevent ensuing chronic diseases.

Camargos, S. M., L. M. V. Soares, et al. (2002). "Accumulation of fumonisins B-1 and B-2 in freshly harvested Brazilian commercial maize at three locations during two nonconsecutive seasons." Mycopathologia 155(4): 219-228. ://000180440600008 Fifty-six Brazilian commercial maize cultivars were examined for FB1 and FB2 accumulation after two nonconsecutive growing seasons. During the 94/95 growing season 35 cultivars were planted at three locations in the state of Sao Paulo, Brazil. All samples (total of 105) were contaminated (0.10 mug/g-6.58 mug/g FB1 and 0.04 mug/g-2.15 mug/g FB2). During the 97/98 growing season, 8 of the cultivars used during 94/95 and 21 others were replanted at the same locations. All 87 samples were contaminated (1.15 mug/g-43.80 mug/g FB1 and 0.08 mug/g- 11.65 mug/g FB2). One cultivar accumulated significantly less fumonisins in all locations during both growing seasons, indicating that some degree of selection may be possible even in climates that favor F. moniliforme (verticillioides) infection of maize. The presence of water surplus in soil from kernel maturity to harvest correlated with concentrations of FB1 in the grain for the 8 cultivars planted during both seasons at three locations. Observed trends indicated that water excesses and deficits from silking to harvest increased fumonisin levels. The difference in the incidence of FB1, FB2, and FB1 + FB2 was significant between growing seasons, planting locations and between cultivars. Neither the level of hybridization, nor the type of endosperm, nor the length of the vegetative cycle showed any effect on the FB1 contamination.

Campbell, K. W., A. M. Hamblin, et al. (1997). "Inheritance of resistance to aflatoxin production in the cross between corn inbreds B73 and LB31." Phytopathology 87(11): 1144-1147. ://A1997YD86700009

Campbell, K. W. and D. G. White (1995). "Evaluation of Corn Genotypes for Resistance to Aspergillus Ear Rot, Kernel Infection, and Aflatoxin Production." Plant Disease 79(10): 1039-1045. ://A1995RW79100016

Campbell, K. W. and D. G. White (1995). "Inheritance of Resistance to Aspergillus Ear Rot and Aflatoxin in Corn Genotypes." Phytopathology 85(8): 886-896. ://A1995RP60900010

Campbell, T. C. and L. Stoloff (1974). "Implication of Mycotoxins for Human Health." Journal of Agricultural and Food Chemistry 22(6): 1006- 1015. ://WOS:A1974U808000020

Capasso, R., A. Evidente, et al. (1996). "Fusaric and 9,10-dehydrofusaric acids and their methyl esters from Fusarium nygamai." Phytochemistry 41(4): 1035-1039. ://A1996TX84700006 Fusaric and 9,10-dehydrofusaric acids and their corresponding methyl esters were isolated from the culture filtrates of Fusarium nygamai. The methyl esters were characterized by chemical and spectroscopic methods and reported here for the first time as naturally occurring products. When assayed on tomato leaves and seedlings at 2.7 x 10(-3) and 2 x 10(-4) M, respectively, fusaric and 9,10-dehydrofusaric acids and their methyl esters showed wide chlorosis rapidly evolving into necrosis as well as a strong inhibition of root elongation, respectively. When assayed at 10(-4) M on brine shrimps (Artemia salina), fusaric and 9,10-dehydrofusaric acids did not prove to be toxic, while their methyl esters showed a toxicity level of 50%, expressed as mortality.

Cardwell, K. F. and P. J. Cotty (2002). "Distribution of Aspergillus section flavi among field soils from the four agroecological zones of the Republic of Benin, West Africa." Plant Disease 86(4): 434-439. ://000174479100020 Certain members of Aspergillus section Flavi produce carcinogenic and immunotoxic metabolites called aflatoxins. These fungi perennate in soils and infect maize grain in the field and in storage. The distribution of Aspergillus section Flavi across the four different agroecologies of Benin Republic was determined. The four agroecological zones range from humid equatorial tropics in the south to the dry savanna near the Sahara desert in the north. Soil samples collected in 1994 to 1996 from 44 different maize fields in Benin were assayed over 3 years (88 samples total) for fungi in Aspergillus section Flavi. All soils tested contained A. flavus. Isolates (1,454 total) were collected by dilution plate from the soils and existed in populations ranging from <10 to >200 CFU/g of soil. CFU counts did not differ from year to year or change significantly with cropping systems within a zone, but differed significantly among zones. Incidence of A. flavus strain isolations varied from south to north, with greater number of CFU of L strain isolates in southern latitudes and higher numbers of CFU of S strain isolates found in the north. The L strain isolates occurred in 81 of 88 samples, whereas S strain isolates were in only 41 of 88 soil samples. Of 96 L strain isolates tested, 44% produced aflatoxins. Only B toxins were produced, and toxigenic isolates averaged over 100 mug of aflatoxin B-1 per 70 ml of fermentation medium (similar to1.4 ppm). All S strain isolates produced both B and G aflatoxins, averaging over 557 mug of aflatoxin B, per 70 ml (8 ppm) and 197 mug of aflatoxin G, per 70 ml of fermentation medium (2.8 ppm). A. parasiticus and A. tamarii were present in less than 10% of the fields and were not associated with any particular agroecological zone.

Cardwell, K. F., J. G. Kling, et al. (2000). "Interactions between Fusarium verticillioides, Aspergillus flavus, and insect infestation in four maize genotypes in lowland Africa." Phytopathology 90(3): 276-284. ://000085499400011 and http://www.botanischergarten.ch/Mycotoxins/Cardwell-Interactions-Phytopath.pdf An experiment was designed to compare cycles of selection of four maize genotypes for ear- and grain-quality characteristics, interactions with Aspergillus flavus and Fusarium verticillioides infection, and insect ear infestation in two seasons. Mean infection levels by A. flavus and F. verticillioides were significantly higher in inoculated rows than in the controls. The F. verticillioides- inoculated rows had significantly more coleopteran beetles and lepidopteran borers per ear than the controls and A. flavus- inoculated rows. Genotypes and cycles of selection within genotype were not different with respect to number of insects or percent fungal incidence in the ear, but they were different for husk extension, field weight, 100-grain weight, and grain density. Inoculation with either fungus resulted in significantly higher percentage of floaters (i.e., loss of grain density) and lower grain weight than the controls. Aflatoxin (B1 and B2) in A. flavus-inoculated rows averaged 327 ppb in the first season and 589 ppb in the second (dryer) season. Fumonisin levels in F: verticillioides-inoculated rows did not differ between seasons, with an average of 6.2 ppm across seasons. In the noninoculated control rows, fumonisin was significantly higher in the first (5.3 ppm) than in the second (3.1 ppm) season. For all genotypes, husk extension and yield parameters decreased in the fungal-inoculated treatments. General ear-rot scoring was significantly correlated with incidence of F. verticillioides in kernels and grain-weight loss but not with A. flavus in the grain.

Carpenter, J. E., S. Sankula, et al. (2004). Insecticidal Bacillus thurgingiensis plants versus chemical insecticides. Agricultural Biotechnology: Challenges and Prospects. WASHINGTON, AMER CHEMICAL SOC: 37-51. ://000189476000004 Genetically engineered crop plants express insecticidal proteins from Bacillus thuringiensis (Bt) are compared to conventional insect control practices using chemical insecticides in terms of ease of use, efficacy, cost and adoption. These new varieties have been commercialized and adopted for field corn and cotton. Bt varieties of sweet corn and potatoes have been approved but not adopted by growers. Several other crops have been engineered to express Bt proteins, including sweet corn, potatoes, soybeans and peanuts. Corn growers have increased yields while cotton growers have reduced insecticide use by 3 million pounds annually. Projected benefits are presented for crops in development.

Cary, J. W., N. Barnaby, et al. (1999). "Isolation and characterization of experimentally induced, aflatoxin biosynthetic pathway deletion mutants of Aspergillus parasiticus." Applied Microbiology and Biotechnology 51(6): 808-812. ://000081207300012 A plasmid vector (pDEL2) was engineered for the purpose of introducing a deletion within the aflatoxin (AF) biosynthetic gene cluster of Aspergillus parasiticus. The vector was constructed by PCR amplification of a region of the AF gene cluster from an A. parasiticus isolate that had undergone an aberrant recombinational event during transformation with. a norA-niaD gene disruption vector. This recombinational event resulted in the deletion of an approximately 6-kb region of the AE gene cluster and accumulation of the AF precursor averantin (AVN). Northern hybridization analysis confirmed that the deletion event resulted in no detectable transcription of the norA gene or the AF biosynthetic genes, avnA, verA, and vev-1. Transformation of A. parasiticus RHN1 with pDEL2 resulted in 16% of the transformants accumulating AVN. Southern hybridization analysis of randomly selected AVN- accumulating transformants indicated that all had undergone a double- crossover homologous, recombinational event resulting in the 6- kb norA to avnA deletion within the AF gene cluster. Aflatoxin precursor feeding studies performed on one of the AVN- accumulating, RHN1(pDEL2) transformants confirmed that the enzyme activities associated with the deleted genes were no longer present.

Cary, J. W. and D. Bhatnagar (1995). "Nucleotide-Sequence of a Aspergillus-Parasiticus Gene Strongly Repressed by Thiamine." Biochimica Et Biophysica Acta-Gene Structure and Expression 1261(2): 319-320. ://A1995QQ95200025 A cDNA clone demonstrating a high degree of homology to the thiamine repressed nmt1 gene of Schizosaccharomyces pombe was isolated from the aflatoxigenic fungus; Aspergillus parasiticus. The deduced polypeptide of a cDNA clone from A. parasiticus had an amino acid sequence identity of 60% with that of the nmtI gene of S. pombe. Transcription of the nmt1 gene homolog in the fungus was strongly inhibited by concentrations of thiamine of 2.0 mu M or higher.

Cary, J. W., K. Ehrlich, et al. (1996). "Molecular and biochemical analysis of the norA gene involved in the biosynthesis of aflatoxin by Aspergillus parasiticus." Faseb Journal 10(6): 3013-3013. ://A1996UK86103243

Cary, J. W., K. C. Ehrlich, et al. (2000). "Generation of aflR disruption mutants of Aspergillus parasiticus." Applied Microbiology and Biotechnology 53(6): 680-684. ://000088164300009 The aflR gene of Aspergillus parasiticus and A. flavus encodes a binuclear zinc-finger, DNA-binding protein, AflR, responsible for activating the transcription of all known aflatoxin biosynthetic genes including itself. Studies to determine how environmental and nutritional factors affect aflR expression and hence aflatoxin production in A. parasiticus have been difficult to perform due to the lack of aflR "knockout" mutants. Transformation of an O-methylsterigmatocystin (OMST)- accumulating strain of A. parasiticus with an aflR-niaD gene disruption vector resulted in clones harboring a recombinationally inactivated aflR gene which no longer produced OMST or aflR transcript. By transformation of this aflR disruptant strain with constructs containing mutated versions of the aflR promoter, we identified three cis-acting sites that were necessary for aflR function: an AflR-binding site, a PacC-binding site, and a G + A-rich site near the transcription start site of aflR.

Cary, J. W., M. Wright, et al. (1996). "Molecular characterization of an Aspergillus parasiticus dehydrogenase gene, norA, located on the aflatoxin biosynthesis gene cluster." Applied and Environmental Microbiology 62(2): 360-366. ://A1996TT69000009 An Aspergillus parasiticus cDNA library was screened with monoclonal antibody raised against a purified A. parasiticus 43-kDa protein demonstrating norsolorinic acid reductase (NOR) activity. One immunopositive clone contained a cDNA insert of 1,418 bp. DNA sequence analysis of this cDNA identified an open reading frame of 1,167 bp that represented the nord gene. The deduced amino acid sequence of the norA coding region consisted of 388 residues capable of encoding a polypeptide of 43.7 kDa. Southern blot analysis of genomic DNA from A. parasiticus indicated that there may be an additional copy of norA. Western blot (immunoblot) analysis of crude protein extracts of A. parasiticus mycelia demonstrated a band of reactivity at 43 kDa only when the fungus was grown in a medium conducive to aflatoxin biosynthesis. Northern (RNA) blot analysis of total RNA from the fungus demonstrated a band of hybridization at about 1.5 kb. As observed with the fungal NORA protein, the norA transcript was present only when the fungus was grown in medium conducive to aflatoxin biosynthesis. Hybridization of the norA cDNA,with cosmid DNAs known to encompass a major portion of the A. parasiticus and Aspergillus flavus aflatoxin biosynthetic pathway gene cluster placed the norA gene coding region just upstream of the ver-1 gene. The deduced amino acid sequence of norA had 49% aminoacid identity with that of an aryl-alcohol dehydrogenase (aad) gene from Phanerochaete chrysosporium.

CAST Council for Agricultural Science and Technology (2003). Mycotoxins: Risks in Plant, Animal, and Human Systems. Task force report, ISSN 0194-4088 ; no. 139). C. C. f. A. S. a. Technology. Ames, Iowa State University: 217.

Executive Summary

Introduction It has been nearly 40 years since modern mycotoxicology, as it might be termed, began with the discovery of the aflatoxins. Since that time, numerous other mycotoxins (toxic metabolites of fungi) have been discovered, many of which were later found to be causes of intoxications (mycotoxicoses) while others remained as laboratory curiosities. Studies directed at mycotoxins, including their detection, biosynthesis, and toxicology along with studies on the epidemiology and control of the producing fungi, are critical to maintaining a safe food supply. The total number of mycotoxins is not known, but toxic metabolites of fungi potentially could number in the thousands. The number of mycotoxins actually known to be involved in disease is considerably less, but even this number is difficult to assess due to the diversity of effects of these unique compounds on animal systems. Not only are the mycotoxins of concern for human and animal diseases, but the plant pathogenic nature of many of the mycotoxin-producing fungi are of considerable economic concern in crops. The results of their plant pathogenic activities raise food safety concerns and impact grain trade and marketing of food and feed. Major Classes of Mycotoxins The major classes of mycotoxins are aflatoxins, trichothecenes, fumonisins, zearalenone, ochratoxin A, and ergot alkaloids. The aflatoxins are produced primarily by Aspergillus flavus and A. parasiticus and they are important agents of disease; their effects range from acute death to chronic disease such as tumors. The trichothecenes are a large class of mycotoxins produced by several fungal genera. Fusarium species are the most notable, but Stachybotrys is a significant producer of selected trichothecenes as well. Likely the most common occurring trichothecene is deoxynivalenol (DON or vomitoxin), which can be a significant contaminant of wheat, barley, and corn. T- 2 toxin is another trichothecene found more frequently in grains in Europe than in the United States. The fumonisins occur primarily in corn and are produced by F. verticillioides, an almost-universal pathogen of corn. These toxins are capable of causing significant disease in horses and swine and have been shown to be carcinogenic in rats and mice. Zearalenone is produced primarily by F. graminearum and causes vulvovaginitis and estrogenic responses in swine. It also may co-occur with DON in grains such as wheat, barley, oats, and corn. The ochratoxins are produced primarily by Penicillium verrucosum and cause significant disease in animals, especially swine, and may be the causal agent of an endemic kidney disease in the Balkan countries. Ergot alkaloids are produced primarily by several species of Claviceps that are plant pathogenic, and elaborate their toxins in specialized masses of fungal tissue called sclerotia. Ergotism is one of the oldest recognized mycotoxicoses. Minor Classes of Mycotoxins The minor class of mycotoxins has representatives that occasionally are associated with mycotoxicoses of humans and other animals, or that occur frequently in selected substrates but have never been found associated with human or other animal disease. Mycotoxin Formation In many cases, mycotoxins are formed in the field during the growing season; however, they also are formed or increased during harvest, drying, and storage. Most important in this process of mycotoxin production is the availability of water for growth of the producing fungus. Temperature, however, is an important factor as well. Thus, when the interaction of the plant and the fungus takes place, moisture and temperature greatly affect plant growth and health and the competitiveness of the mycotoxigenic fungus. In grain storage, the factors of water activity, sub strate aeration and temperature, inoculum concentrations, microbial interactions, mechanical damage, and insect infestation can play a role in mycotoxin contamination. Mycotoxin-Producing Fungi and Their Control Mycotoxins are produced by a wide array of diverse fungal species that generally are not aggressive pathogens. They are adapted for colonization and growth on substrates with a wide range of moisture availability and nutritional content. Most of the mycotoxins that are considered to be important are produced primarily by three genera of fungi, namely, Aspergillus, Penicillium, and Fusarium. Claviceps and Stachybotrys also are important producers of mycotoxins. Within the genus Aspergillus, the major class of mycotoxins, are the aflatoxins. The crops most usually affected are corn, cotton, peanuts, and certain tree nuts. Aspergillus flavus is a cause of ear rot in corn where conidia from the soil-inhabiting organism are carried to the silks of the corn plant and, under suitable environmental conditions, infections can occur. The production of aflatoxin can continue until the moisture in the kernels reaches about 15%. Peanuts are contaminated and infection occurs during hightemperature and low-moisture stress. In cotton, insects often play a role in the entry of the organism into the cotton bolls. In pistachios, a phenomenon whereby the hulls split prior to maturity allows for a portal of entry for the fungus. In both pistachios and almonds, however, contamination may involve damage by insect larvae. Although not conclusive in all crops, high temperatures seem to play a role in aflatoxin contamination. A number of control strategies for aflatoxin contamination in crops are being investigated and include controlling preharvest stress on the crop where possible, establishing breeding programs for resistance, and assessing potential biocontrol agents. Within the genus Fusarium, there are a number of important mycotoxin-producing species. Some important plant pathogens are in this genus and are causes of wilts and scab or blight diseases of small grains. Ear rot also can be caused by Fusarium. Fusarium graminearum is the major causative agent; however, other species such as F. verticillioides, F. proliferatum, and F. subglutinans may cause ear rot. These latter agents may produce fumonisins during the pathogenic state in corn. Fusarium graminearum is a significant pathogen on wheat, barley, and oats and is a major producer of DON in these grains. This organism also is capable of producing zearalenone in various commodities including corn. The organism survives in crop residue, which is a source of inoculum for the next year’s crop. Control strategies for these infections and production of mycotoxins are being investigated and include elimination of the residue on the field soil through deep tillage, irrigation during drought stress, breeding for pathogen and insect- resistance, and genetic engineering. Penicillium spp. are more typically associated with storage of crops and the production of mycotoxins such as ochratoxin. Ochratoxin usually is formed in storage or during drying of certain commodities for processing. A number of fungi are capable of producing toxic alkaloids, and Claviceps spp. are the most notable in this regard. This organism is known as a replacement parasite in that it replaces plant structures with fungal tissue called ergots or sclerotia. These fungal bodies often contain toxic amounts of alkaloids leading to the disease known as ergotism in humans and other animals consuming them. Ergotism is one of the oldest known mycotoxicoses in humans and occurs following the incorporation, by several different processes, of the ergots in grain used in preparing food. Toxic alkaloids also are produced by the genera Epichloe and Neotyphodium, both of which can be endophytic in certain plant species such as fescue and ryegrass. Control of ergot is attempted by pasture management practices and, for endophytic relationships, the control efforts are aimed primarily at decreasing the toxicity of the endophytic fungus through selection. Stachybotrys is a cellulolytic saprophyte that can be found in a variety of commodities and the trichothecene metabolites of this organism can produce disease similar to some of those produced by Fusarium spp. Recently, this organism seemed to be involved in human disease where building materials were contaminated with the organism and possibly its toxic metabolites. Timely harvest, cleaning and drying of the crop, controlling temperature and moisture during storage, and using antifungal agents can assist in decreasing or eliminating mycotoxins in food and feed. Furthermore, research efforts to understand the genetic and biosynthetic aspects of mycotoxin development may lead to control strategies in grains. While the exact reasons that mycotoxins are produced by fungi are unknown, certain mycotoxins seem to function as potential virulence factors in producing disease in both plants and animals.

Castegnaro, M., L. Garren, et al. (1998). "Analytical method for the determination of sphinganine and sphingosine in serum as a potential biomarker for fumonisin exposure." Journal of Chromatography B-Analytical Technologies in the Biomedical and Life Sciences 720(1-2): 15-24. ://000077810400003 The toxins produced by Fusarium moniliforme, which include fumonisins, are possible human carcinogens. Fumonisins are inhibitors of de novo sphingolipid biosynthesis. Alterations of the ratio of sphinganine (Sa) to sphingosine (So) in urine and serum has been proposed as a possible biomarker of exposure to this toxin. A new method was developed for their analysis in tissues and urine. This work describes the further adaptation of the method to the analysis of Sa and So in serum and its validation in sera of untreated and fumonisin B-1 (FB1) treated rats and mice. No significant differences in the Sa/So ratios were observed in the FB, treated rats. In mice, the increase was only of marginal statistical significance. Determination of Sa/So ratios in human sera could readily be made in small volumes (from 0.3 to 0.5 ml) of serum. (C) 1998 Elsevier Science B.V. All rights reserved.

Catangui, M. A. and R. K. Berg (2006). "Western bean cutworm, Striacosta albicosta (Smith) (Lepidoptera : Noctuidae), as a potential pest of transgenic Cry1Ab Bacillus thuringiensis corn hybrids in South Dakota." Environmental Entomology 35(5): 1439-1452. ://WOS:000241170600038 Injuries caused by the western bean cutworm, Striacosta albicosta (Smith), on transgenic Cry1Ab Bacillus thuringiensis (Bt) corn hybrids were documented and quantified. The western bean cutworm is an emerging or potential pest of transgenic Bt corn in South Dakota. The proportion of ears infested with western bean cutworm larvae in the Cry1Ab Bt corn hybrids were 18-20, 38-70, and 0- 34% in 2000, 2003, and 2004, respectively. The Cry1Ab Bt corn hybrids were almost completely free of European corn borer infestations. Untreated conventional corn hybrids were less infested with western bean cutworm larvae but more infested with European corn borer larvae. The proportion of ears infested with European corn borer larvae alone were 33,58-80, and 8-25% in 2000,2003, and 2004, respectively. Infestations with western bean cutworm alone were 28, 8-28, and 13-19%, respectively. Proportion of ears simultaneously infested with both western bean cutworm and European corn borer larvae were much lower than single infestations by either species alone, indicating niche overlap and competition. Simultaneous infestations by the two species on untreated conventional corn hybrids were only 8,0-18, and 0-1% in 2000,2003, and 2004. The corn grains harvested from injured ears were also analyzed for fumonisin and aflatoxin through quantitative enzyme-linked immunosorbent assays. More mycotoxins were found in 2003 when the levels of insect infestation in the corn ears were higher than in 2004. Results from this study underscore the need to investigate other emerging or potential arthropod pests of transgenic Bt corn hybrids in addition to the western bean cutworm.

Cawood, M. E., W. C. A. Gelderblom, et al. (1994). "Interaction of C-14-Labeled Fumonisin-B Mycotoxins with Primary Rat Hepatocyte Cultures." Food and Chemical Toxicology 32(7): 627-632. ://A1994PB00800006 An in vitro study on the interaction and biotransformation of the [C-14]fumonisin B mycotoxins was conducted, using primary rat hepatocyte cultures and subcellular enzyme preparations. At the same concentration, fumonisin B-2 (FB2) exhibited a higher cytotoxicity and specific binding to primary rat hepatocytes than fumonisin B-1 (FB1). However, if the effective dose level (EDL) is considered (i.e. the lowest level of toxin that binds to the hepatocytes to elicit a cytotoxic effect), FB1 and FB2 exhibited a similar cytotoxic effect. FB1 was found to be associated with both the soluble and insoluble compartments within the cell. As assessed by the radioactivity associated with the cellular preparations, very little (approximately 0.01%) FB1 and/or FB2 bound to hepatocytes. In the subsequent fractionation of the culture medium using amberlite XAD-2 and silica-gel chromatography, no metabolites were detected, indicating that the fumonisin molecule was not metabolized by primary hepatocytes. The latter aspect was confirmed by the fact that incubation of FB1 with microsomal enzyme preparations also failed to indicate any metabolism of the fumonisins by the esterases or by cytochrome P-450 monooxygenase. FB1 was also found not to be a substrate for the triglyceride hepatic endothelial lipase, nor for a lipase from porcine pancreas. This study supports further the hypothesis that the intact molecule of the fumonisins is required for biological activity.

Cawood, M. E., W. C. A. Gelderblom, et al. (1991). "Isolation of the Fumonisin Mycotoxins - a Quantitative Approach." Journal of Agricultural and Food Chemistry 39(11): 1958-1962. ://A1991GQ61400014 A method for the preparative-scale isolation of the fumonisin B (FB) mycotoxins, from corn cultures of Fusarium moniliforme, is described and quantitatively evaluated. Eighty percent of FB1 and 60% of FB2 were recovered after extraction with CH3OH/H2O (3:1). The fumonisins, including the newly discovered FB3 and FB4, were purified using Amberlite XAD-2, silica gel, and reverse- phase C18 chromatography. The Amberlite XAD-2 purification step proved to be the most effective cleanup procedure, while subsequent chromatography on silica gel and RP C18 effectively separate the individual fumonisins to a purity of over 90%. The relatively low final yield (40%) of FB1 and FB2 may be ascribed to (1) the strong affinity of FB1 for silica gel, (2) the low initial recovery (60%) of FB2, and (3) the formation of monomethyl and dimethyl esters of FB1 and FB2, as well as their interference in the purification of the individual fumonisins. The N-acetyl derivatives of FB1 and FB2 were also purified and shown to be metabolites of F. moniliforme.

Cazzaniga, D., J. C. Basilico, et al. (2001). "Mycotoxins inactivation by extrusion cooking of corn flour." Letters in Applied Microbiology 33(2): 144-147. ://000170102700010 Aims: To evaluate the effects of the extrusion cooking process on the inactivation of mycotoxins in corn flour. Methods and Results: Samples of corn flour experimentally contaminated with aflatoxin B-1 (AFB1) (50 ppb) and deoxynivalenol (DON) (5 ppm) were extruded. The effects of three extrusion variables (flour moisture, extrusion temperature and sodium metabisulphite addition) were analysed according to a two-level factorial design. The process was effective for the reduction of DON content (higher than 95%) under all the conditions assessed, but was only partially successful (10-25%) for the decontamination of AFB1. Conclusions: Extrusion cooking is effective for the inactivation of DON but is of limited value for AFB1, even if metabisulphite is added. More severe extrusion conditions are needed for the detoxification of AFB1. Significance and Impact of the Study: As contamination with DON occurs mainly in the field prior to harvesting and that of AFB1 is normally produced during grain storage, maize is often contaminated with DON but not with AFB1. Under these conditions, the described extrusion process can be used for the detoxification of DON. The addition of sodium metabisulphite did not significantly affect the inactivation of AFB1. Extrusion cooking is therefore an appropriate treatment for vomitoxin-contaminated maize in countries where, because of the prevailing conditions, these are the only toxins present.

Chang, P. K., D. Bhatnagar, et al. (1993). "Disruption of Aflatoxin Biosynthetic-Pathway through Genetic Complementation in Aspergillus- Parasiticus." Faseb Journal 7(7): A1229-A1229. ://A1993KY84801110

Chang, P. K., D. Bhatnagar, et al. (1995). "Sequence Variability in Homologs of the Aflatoxin Pathway Gene Aflr Distinguishes Species in Aspergillus Section Flavi." Applied and Environmental Microbiology 61(1): 40-43. ://A1995PY86700007 The Aspergillus parasiticus aflR gene, a gene that may be involved in the regulation of aflatoxin biosynthesis, encodes a putative zinc finger DNA-binding protein. PCR and sequencing were used to examine the presence of aflR homologs in other members of Aspergillus Section Flavi. The predicted amino acid sequences indicated that the same zinc finger domain, CTSCASSKVRCTKEKPACARCIERGLAC, was present in all of the Aspergillus sojae, Aspergillus flavus, and Aspergillus parasiticus isolates examined and in some of the Aspergillus oryzae isolates examined. Unique base substitutions and a specific base deletion were found in the 5' untranslated and zinc finger region; these differences provided distinct fingerprints. A. oryzae and A. flavus had the T- G-A-A-X-C fingerprint, whereas A. parasiticus and A. sojae had the C-C-C- C-C-T fingerprint at the corresponding positions. Specific nucleotides at positions -90 (C or T) and -132 (G or A) further distinguished ii. flavus from A. oryzae and A. parasiticus from A. sojae, respectively. A. sojae ATCC 9362, which was previously designated A. oryzae NRRL 1988, was determined to be a A. sojae strain on the basis of the presence of the characteristic fingerprint, A-C-C-C-C-C C-T, The DNAs of other members of Aspergillus Section Flavi, such as Aspergillus nomius and Aspergillus tamarii, and some isolates of A. oryzae appeared to exhibit low levels of similarity to the A. parasiticus aflR gene since low amounts of PCR products or no PCR products were obtained when DNAs from these strains were used.

Chang, P. K., J. W. Cary, et al. (1993). "Cloning of the Aspergillus-Parasiticus Apa-2 Gene Associated with the Regulation of Aflatoxin Biosynthesis." Applied and Environmental Microbiology 59(10): 3273-3279. ://A1993MA35300017 An Aspergillus parasiticus gene, designated apa-2, was identified as a regulatory gene associate with aflatoxin biosynthesis. The apa- 2 gene was cloned on the basis of overproduction of pathway intermediates following transformation of fungal strains with cosmid DNA containing the aflatoxin biosynthetic genes nor-1 and ver-1. Transformation of an 0-methylsterigmatocystin-accumulating strain, A. parasiticus SRRC 2043, with a 5.5-kb HindIII-XbaI DNA fragment containing apa-2 resulted in overproduction of all aflatoxin pathway intermediates analyzed. Specific enzyme activities associated with the conversion of norsolorinic acid and sterigmatocystin were increased approximately twofold. The apa-2 gene was found to complement an A. flavus afl-2 mutant strain for aflatoxin production, suggesting that apa-2 is functionally homologous to afl-2. Comparison of the A. parasiticus apa-2 gene DNA sequence with that of the A. flavus afl-2 gene (G. A. Payne, G. J. Nystorm, D. Bhatnagar, T. E. Cleveland, and C. P. Woloshuk, Appl. Environ. Microbiol. 59:156-162, 1993) showed that they shared >95% DNA homology. Physical mapping of cosmid subclones placed apa-2 approximately 8 kb from ver-1.

Chang, P. K., J. W. Cary, et al. (1995). "The Aspergillus-Parasiticus Polyketide Synthase Gene Pksa, a Homolog of Aspergillus-Nidulans Wa, Is Required for Aflatoxin B-1 Biosynthesis." Molecular & General Genetics 248(3): 270-277. ://A1995RT23600004 Aflatoxins comprise a group of polyketide-derived carcinogenic mycotoxins produced by Aspergillus parasiticus and Aspergillus flavus. By transformation with a disruption construct, pXX, we disrupted the aflatoxin pathway in A. parasiticus SRRC 2043, resulting in the inability of this strain to produce aflatoxin intermediates as well as a major yellow pigment in the transformants. The disruption was attributed to a single- crossover, homologous integration event between pXX and the recipient A. parasiticus genome at a specific locus, designated pksA. Sequence analysis suggest that pksA is a homolog of the Aspergillus nidulans wA gene, a polyketide synthase gene involved in conidial wall pigment biosynthesis. The conserved beta-ketoacyl synthase, acyltransferase and acyl carrier- protein domains were present in the deduced amino acid sequence of the pksA product. No beta-ketoacyl reductase and enoyl reductase domains were found, suggesting that pksA does not encode catalytic activities for processing beta-carbon similar to those required for long chain fatty acid synthesis. The pksA gene is located in the aflatoxin pathway gene cluster and is linked to the nor-1 gene; an aflatoxin pathway gene required for converting norsolorinic acid to averantin. These two genes are divergently transcribed from a 1.5 kb intergenic region. We propose that pksA is a polyketide synthase gene required for the early steps of aflatoxin biosynthesis.

Chang, P. K., K. C. Ehrlich, et al. (1996). "Characterization of the Aspergillus parasiticus niaD and niiA gene cluster." Current Genetics 30(1): 68- 75. ://A1996UV82300011 The nitrate reductase gene (niaD) and nitrite reductase gene (niiA) of Aspergillus parasiticus are clustered and are divergently transcribed from a 1.6-kb intergenic region (niaD- niiA). The deduced amino-acid sequence of the A. parasiticus nitrate reductase demonstrated a high degree of homology to those of other Aspergillus species, as well as to Leptosphaeria maculans, Fusarium oxysporum, Gibberella fujikuroi and Neurospora crassa, particularly in the cofactor-binding domains for molybdenum, heme and FAD. A portion of the deduced nitrite reductase sequence was homologous to those of A. nidulans and N. crassa. The nucleotide sequences in niaD-niiA of A. parasiticus and of A. oryzae were 95% identical, indicating that these two species are closely related. Several GATA motifs, the recognition sites for the N. crassa positive-acting global regulatory protein NIT2 in nitrogen metabolism, were found in A. parasiticus niaD-niiA. Two copies of the palindrome TCCGCGGA and other partial palindromic sequences similar to the target sites for the pathway specific regulatory proteins, N. crassa NIT4 and A. nidulans NirA, in nitrate assimilation, were also identified. A recombinant protein containing the A. nidulans AreA (the NIT2 equivalent) zinc finger and an adjacent basic region was able to bind to segments of niaD-niiA encompassing the GATA motifs. These results suggest that the catalytic and regulatory mechanisms of nitrate assimilation are well conserved in Aspergillus.

Chang, P. K., K. C. Ehrlich, et al. (1995). "Increased Expression of Aspergillus-Parasiticus Aflr, Encoding a Sequence-Specific DNA-Binding Protein, Relieves Nitrate Inhibition of Aflatoxin Biosynthesis." Applied and Environmental Microbiology 61(6): 2372-2377. ://A1995RA62100047 The aflR gene from Aspergillus parasiticus and Aspergillus flavus may be involved in the regulation of ah aflatoxin biosynthesis. The aflR gene product, AFLR, possesses a GAL4- type binuclear zinc finger DNA-binding domain. A transformant, SU1-N3(pHSP), containing an additional copy of aflR, showed increased transcription of aflR and the aflatoxin pathway structural genes, nor-1, ver- 1, and omt-1, when cells were grown in nitrate medium, which normally suppresses aflatoxin production. Electrophoretic mobility shift assays showed that the recombinant protein containing the DNA-binding domain, AFLR1, bound specifically to the palindromic sequence, TTAGGCCTAA, 120 bp upstream of the AFLR translation start site. Expression of aflR thus appears to be autoregulated. Increased expression of aflatoxin biosynthetic genes in the transformant might result from an elevated basal level of AFLR, allowing it to overcome nitrate inhibition and to bind to the aflR promotor region, thereby initiating aflatoxin biosynthesis. Results further suggest that aflR is involved in the regulation of multiple parts of the aflatoxin biosynthetic pathway.

Chang, P. K., J. J. Yu, et al. (1999). "The carboxy-terminal portion of the aflatoxin pathway regulatory protein AFLR of Aspergillus parasiticus activates GAL1 :: lacZ gene expression in Saccharomyces cerevisiae." Applied and Environmental Microbiology 65(6): 2508-2512. ://000080624300034 AFLR, a DNA-binding protein of 444 amino acids, transactivates the. expression of aflatoxin biosynthesis genes in Aspergillus parasiticus and Aspergillus flavus, as well as the sterigmatocystin synthesis genes in Aspergillus nidulans. We show here by fusion of various aflR coding regions to the GAL4 DNA-binding coding region that the AFLR carboxyl terminus contained a region that activated GAL1::lacZ gene expression in Saccharomyces cerevisiae and that the AFLR internal region was required for the activation activity. Compared to the AFLR carboxy-terminal fusion protein (AFLRC), a mutant AFLRC retained approximately 75% of the activation activity after deletion of three acidic amino acids, Asp365, Glu366, and Glu367, in a previously identified acidic: stretch. Removal of the carboxy-terminal amino acid, Glu444, did not affect the activation activity. Substitutions of acidic. Glu423, Asp439, or Asp436/Asp439 with basic, amino acids, Lys and His, resulted in 10- to 15-fold-lower activation activities. Strikingly, the Asp436His mutation abolished the activation activity. Substitutions of basic His428 and His442 with acidic Asp resulted in 20 and. 40% decreases in the activation activities, respectively. Simultaneous substitutions of Arg427, Arg429, and Arg431 with Leu also significantly decreased the activation activity; the decrease was approximately 50-fold. Results suggest that the AFLR carboxy- terminal region is involved in transcription activation and that total acidity in this region is not a major determinant of;AFLR's activation ability in S. cerevisiae.

Chang, P. K., J. J. Yu, et al. (1999). "Repressor-AFLR interaction modulates aflatoxin biosynthesis in Aspergillus parasiticus." Mycopathologia 147(2): 105-112. ://000088360000006 Regulation of aflatoxin (AF) biosynthesis likely involves a complex interplay of positive- and negative-acting factors that are affected by physiological cues responsive to internal and external stimuli. These factors, presumably, modulate the expression of the AF pathway-specific regulatory gene, aflR, whose product, AFLR, a zinc cluster transcription factor, then turns on or off the transcription of other AF genes. To determine if the AFLR carboxyl region (AFLRC) interacts with positive- or negative-acting proteins, we fused the Aspergillus parasiticus aflR carboxyl coding region (aflRC) to the promoter of A. parasiticus nitrite reductase gene (niiA(p)::aflRC), and transformed it into A. parasiticus SRRC 2043. Transformants that contained two copies of niiA(p)::aflRC, one at the niaD locus and another at the aflR locus, overproduced AF precursors independent of the nitrogen source. The higher copy number of the integrated niiA(p)::aflRC correlated with increased production of AF precursors by the transformants as well as increased expression of both aflRC and native aflR in potato dextrose broth and A & M medium. Since aflRC does not encode a DNA-binding domain, the expressed AFLRC should not bind to the promoters of AF pathway genes and affect transcription directly. The results are consistent with AFLRC titrating out a putative repressor that interacts with AFLR under different growth conditions and modulates AF biosynthesis. This interaction also indirectly affects sclerotial development.

Chang, P. K., J. J. Yu, et al. (2000). "Characterization of the Aspergillus parasiticus major nitrogen regulatory gene, areA." Biochimica Et Biophysica Acta-Gene Structure and Expression 1491(1-3): 263-266. ://000086661000026 The major nitrogen regulatory gene, areA, was cloned from Aspergillus parasiticus. It encoded a polypeptide of 864 amino acids which contained a nuclear localization signal (NLS), a highly acidic region from positions 497 to 542, a Cys-X-2-Cys- X-17-Cys-X-2-Cys DNA-binding motif and a conserved carboxy- terminus. Electrophoretic mobility shift assays suggested that the A. parasiticus AREA DNA-binding domain fusion protein bound cooperatively to single GATA elements in the A. parasiticus niaD-niiA intergenic region. AREA also bound to the aflR-qflJ intergenic region of the aflatoxin biosynthesis gene cluster. Regions of areA were fused to a yeast GAL4 DNA-binding domain coding region to localize putative transcription activation domain(s) of AREA based on activation of the GAL1(p)::lacZ reporter gene expression. The portion between NLS and the acidic domain demonstrated 16-20-fold higher activation activities than other portions of AREA, which suggests that the transcription activation domain is located in this region. (C) 2000 Elsevier Science B.V. All rights reserved.

Chang, P. K., J. J. Yu, et al. (2000). "adhA in Aspergillus parasiticus is involved in conversion of 5 '-hydroxyaverantin to averufin." Applied and Environmental Microbiology 66(11): 4715-4719. ://000165055300016 Two routes for the conversion of 5'-hydroxyaverantin (HAVN) to averufin (AVF) in the synthesis of aflatoxin have been proposed. One involves the dehydration of HAVN to the lactone averufanin (AVNN), which is then oxidized to AVP. Another requires dehydrogenation of HAVN to 5'-ketoaverantin, the open- chain form of AVF, which then cyclizes spontaneously to AVF, We isolated a gene, adhA, from the aflatoxin gene cluster of Aspergillus parasiticus SU-1. The deduced ADHA amino acid sequence contained two conserved motifs found in short-chain alcohol dehydrogenases-a glycine-rich loop (GXXXGXG) that is necessary for interaction with NAD(+)-NADP(+), and the motif YXXXK, which is found at the active site, A. parasiticus SU-1, which produces aflatoxins, has two copies of adhA (adhA1), whereas A. parasiticus SRRC 2043, a strain that accumulates O- methylsterigmatocystin (OMST), has only one copy. Disruption of adhA in SRRC 2043 resulted in a strain that accumulates predominantly HAVN, This result suggests that ADHA is involved in the dehydrogenation of HAVN to AVF. Those adhA disruptants that still made small amounts of OMST also accumulated other metabolites, including AVNN, after prolonged culture.

Chelule, P. K., N. Gqaleni, et al. (2001). "Exposure of rural and urban populations in KwaZulu Natal, South Africa, to fumonisin B-1 in maize." Environmental Health Perspectives 109(3): 253-256. http://ehp.niehs.nih.gov/members/2001/109p253-256chelule/chelule-full.html We surveyed households in rural and urban areas of KwaZulu Natal, South Africa, to assess the exposure of the inhabitants to fumonisin B-1 (FB1), a mycotoxin produced by Fusarium verticillioides. In southern African regions maize, used as a staple food by the population, is prone to F. verticillioides infection. Furthermore, high levels of FB1 in maize have been associated with esophageal cancer in South Africa. We assessed exposure of the population to FB1 at three levels, namely, by analying stored maize, plate-ready food, and frees. The positions of participating households in the rural area were recorded using geographic information systems (GTS) for ease and accuracy of Follow-up. OF the 50 rural maize samples examined, 32% had levels of FB1 ranging from 0.1-22.2 mg/kg, whereas 29% of the 28 cooked maize (phutu) samples contained FB1 ranging from 0.1-0.4 mg/kg. The incidence and levels of FB1 in feces were 33% and 0.5-39.0 mg/kg, respectively. Of the 49 urban maize samples analyzed 6.1% had a range of 0.2-0.5 mg/kg FB1, whereas 3 of 44 fecal samples (6%) ranged between 0.6 and 16.2 mg/kg. No FB1 was detected in urban phutu samples. Because these levels are lower than those published from regions in South Africa with high incidence of esophageal cancer, it may be concluded that the risk of esophageal cancer from FB1 exposure is lower in the KwaZulu Natal region.

Chelule, P. K., H. P. Mbongwa, et al. (2010). "Lactic acid fermentation improves the quality of amahewu, a traditional South African maize- based porridge." Food Chemistry 122(3): 656-661. ://WOS:000278357700028 The ability of traditional amahewu fermentation to increase protein digestibility and detoxify mycotoxins commonly contaminating maize in southern Africa was investigated. Commercial maize meal, with or without a range of added ingredients, was fermented, following the traditional way, and the levels of proteins and amino acids assessed. Traditional amahewu samples (and the maize meal used to prepare them) were also collected from a neighbouring rural village. Mycotoxin levels (aflatoxin B-1, fumonisin B-1 and zearalenone) in maize meal and amahewu were analysed and compared in the two sets of samples. Increased levels of protein were observed in amahewu, especially in the samples with added yeast and bread flour (up to 149%), in comparison to the levels in starter maize. In addition, the mycotoxins detected in maize samples were drastically reduced, by 76.5-100%, following fermentation. This observation shows that traditional amahewu fermentation may improve the nutritional quality of maize-based foods and reduce the levels of toxic/carcinogenic mycotoxins. (C) 2010 Elsevier Ltd. All rights reserved.

Chen, Z. Y., R. L. Brown, et al. (2001). "Comparison of constitutive and inducible maize kernel proteins of genotypes resistant or susceptible to aflatoxin production." Journal of Food Protection 64(11): 1785-1792. ://000172247800023 Maize genotypes resistant or susceptible to aflatoxin production or contamination were compared for differences in both constitutive and inducible proteins. Five additional constitutive proteins were found to be associated with resistance in over 8 of the 10 genotypes examined. Among these, the 58- and 46-kDa proteins were identified as globulin-1 and globulin-2, respectively. Differences in the ability to induce specific antifungal proteins, such as the higher synthesis of the 22-kDa zeamatin in resistant genotypes, were also observed between resistant and susceptible kernels incubated under germinating conditions (31 degreesC, 100% humidity). Both constitutive and inducible proteins appear to be necessary for kernel resistance. Embryo-killed kernels (unable to synthesize new proteins) supported the highest level of aflatoxins, whereas imbibed kernels (to hasten protein induction) supported the lowest among all treatments. This suggests that the synthesis of new proteins by the embryo plays an important role in conferring resistance However, significantly lower levels of aflatoxin production in embryo-killed resistant kernels than in susceptible ones suggest that, in reality, high levels of constitutive antifungal proteins are indispensable to kernel resistance.

Chen, Z. Y., R. L. Brown, et al. (2002). "Identification of unique or elevated levels of kernel proteins in aflatoxin-resistant maize genotypes through proteome analysis." Phytopathology 92(10): 1084-1094. ://000178384100008 Aflatoxins are carcinogens produced by Aspergillus flavus and A. parasiticus during infection of susceptible crops such as maize (Zea mays L.). Resistant maize genotypes have been identified, but the incorporation of resistance into commercial lines has been slow due to the lack of selectable markers. Here we report the identification of potential markers in resistant maize lines using a proteomics approach. Kernel embryo proteins from each of two resistant genotypes have been compared with those from a composite of five susceptible genotypes using large format two-dimensional gel electrophoresis. Through these comparisons, both quantitative and qualitative differences have been identified. Protein spots have been sequenced, and based on peptide sequence homology analysis, are categorized as follows: storage proteins (globulin 1 and globulin 2), late embryogenesis abundant (LEA) proteins related to drought or desiccation (LEA3 and LEA 14), water- or osmo-stress related proteins (WSI18 and aldose reductase), and heat-stress related proteins (HSP16.9). Aldose reductase activity measured in resistant and susceptible genotypes before and after infection suggests the importance of constitutive levels of this enzyme to resistance. Results of this study point to a correlation between host resistance and stress tolerance. The putative function of each identified protein is discussed.

Chen, Z. Y., T. E. Cleveland, et al. (2002). Corn as a source of antifungal genes for genetic engineering of crops for resistance to aflatoxin contamination. Crop Biotechnology. Washington, AMER CHEMICAL SOC. 829: 131-150. ://000181072300011 Aflatoxins are toxic, highly carcinogenic secondary metabolites of Aspergillus flavus and A. parasiticus, produced during fungal infection of a susceptible crop in the field or after harvest, that contaminate food and feed and threaten human and animal health. Natural resistance mechanisms to aflatoxin producing fungi have been identified in corn that could be exploited in plant breeding and/or genetic engineering strategies. Resistant corn lines are being compared to susceptible varieties using proteomics to identify proteins and consequently genes associated with resistance. Antifungal proteins such as ribosomal inactivating proteins, chitinases, protease inhibitors, and lytic peptides have been correlated with increased resistance in corn kernels to invasion by aflatoxigenic fungi. The gene for 14 W trypsin inhibitor (TI), whose increased levels in corn kernels correlated with enhanced resistance to A. flavus, when introduced into tobacco,. greatly enhanced resistance in transformed tobacco plants to attack by Colletotrichum destructivum. Extracts of cotton embryogenic cultures expressing the TI gene product were shown to cause lysis of germinated A. flavus and Verticillium dahliae conidia, in vitro. Comparing resistant corn genotypes to susceptible ones through proteomics, may facilitate the identification of several other resistance-associated proteins.

Chourasia, H. K. (1995). "Mycobiota and Mycotoxins in Herbal Drugs of Indian Pharmaceutical Industries." Mycological Research 99: 697-703. ://A1995RG63700012

Chourasia, H. K. (2001). "Response of some Indian maize samples for aflatoxin production by Aspergillus flavus strains." Journal of Food Science and Technology-Mysore 38(4): 387-389. ://000170621000020 Laboratory response of five maize varieties commonly marketed in Bihar State, India to aflatox:n-producing and -non-producing strains of Aspergillus flavus was studied. Despite the small number of samples studied, it was possible to separate the maize genotypes into three groups according to their response, efficiently producing aflatoxins (good Substrates), no aflatoxins producing (poor substrates) and ambiguous, depending on the strain used as the inoculum.

Cirillo, T., A. Ritieni, et al. (2003). "Evaluation of conventional and organic Italian foodstuffs for deoxynivalenol and fumonisins B-1 and B-2." Journal of Agricultural and Food Chemistry 51(27): 8128-8131. ://000187565600047 AND http://www.botanischergarten.ch/Bt/Cirillo-Evaluation-Fumonisins-2003.pdf Two lots of human foodstuffs from conventional and organic brand foods were purchased from supermarkets and analyzed for three Fusarium toxins, deoxynivalenol, by GC-ECD, and fumonisins B-1 and B-2 (FB1-FB2), by LC-MS. The occurrence of deoxynivalenol contamination was higher than 80% in both organic and conventional foods; fumonisin B-1 was found in 20% of organic foods and in 31% of conventional ones and fumonisin B-2 in more than the 32% of the food samples from both the agricultural practices. The highest median concentration of deoxynivalenol occurred in conventional rice-based foodstuffs (207 mug/kg): that of fumonisin B-1 in conventional maize-based foods (345 mug/kg) and that of fumonisin B-2 in organic wheat- based foods (210 mug/kg).

Clements, M. J., K. W. Campbell, et al. (2003). "Influence of Cry1Ab protein and hybrid genotype on fumonisin contamination and fusarium ear rot of corn." Crop Science 43(4): 1283-1293. ://000183762800006 Fusarium ear rot of corn (Zea mays L.) is associated with feeding damage from the European corn borer (ECB), Ostrinia nubilalis Hubner, and the corn earworm (CEW), Helicoverpa zea Boddie. Specific transformation events encoding for Cry1Ab protein from Bacillus thuringiensis Berliner (Bt) may reduce Fusarium ear rot and fumonisin concentration in grain by minimizing damage from certain insects. The objective of this study was to determine if effects from Cry1Ab protein in kernels and silks on fumonisin concentration in grain vary depending on the genotype of the hybrid or the predominant insect species. Four Bt corn hybrids and their corresponding nontransgenic, near-isogenic hybrids were compared for ear rot severity and fumonisin concentration in grain in four environments. Treatments included inoculation with F. verticillioides (Sacc.) Nirenb. (Syn = F. moniliforme J. Sheld.) and F. proliferatum (Matsushima) Nirenb., infestation with ECB larvae, infestation with CEW larvae, and controls. Cry1Ab protein from the Mon810 transformation event was associated with reduced ear rot severity when hybrids were not inoculated with Fusarium spp., regardless of whether hybrids were infested or not infested with insects. Cry1Ab protein was associated with reduced fumonisin concentration in grain when ECB was the predominant insect, but not when CEW was the predominant insect. Cry1Ab protein was not associated with reduced fumonisin concentration in grain for the most resistant hybrid pair in this study. Results suggest that Bt hybrids can reduce fumonisin concentration in grain during seasons when ECB is favored, but not during seasons when CEW is favored. Hybrid genotype was an important factor in reducing fumonisin concentration in grain.

Clements, M. J., C. E. Kleinschmidt, et al. (2003). "Evaluation of inoculation techniques for fusarium ear rot and fumonisin contamination of corn." Plant Disease 87(2): 147-153. ://000180563600005 Fumonisins have been associated with potentially serious toxicoses of animals and humans. Prior to initiating a corn (Zea mays) breeding program for resistance to these mycotoxins, a efficient inoculation technique must be developed. Four inoculation techniques were evaluated on 14 commercial corn hybrids in Urbana, IL in 1999 and 2000. The techniques were: injection of inoculum through the ear husk leaves at R2 (blister); silks sprayed with inoculum at R2 and covered with a shoot bag until harvest; silks sprayed with inoculum at R2, covered with a shoot bag, reinoculated I week thereafter, and covered with a shoot bag until harvest; and insertion of six Fusarium-colonized toothpicks into the silk channel at R2. Only injection of inoculum through the husk leaves significantly increased the concentration of fumonsin in grain and severity of Fusarium ear rot compared with a control. This technique effectively differentiated hybrids previously identified as resistant or susceptible to Fusarium ear rot. The rank order of hybrids inoculated with this technique did not significantly change in the 2 years of this study. This technique is suitable for efficiently evaluating a large number of corn genotypes for resistance to Fusarium car rot and fumonisin concentration.

Clements, M. J., C. A. Maragos, et al. (2004). "Sources of resistance to fumonisin accumulation in grain and fusarium ear and kernel rot of corn." Phytopathology 94(3): 251-260. ://000220532500006 Fumonisin is a group Of homologous mycotoxins produced by several species of Fusarium. Fumonisin has been associated with Fusarium ear and kernel rot of corn (Zea mays) and several toxicoses of animals and humans. Corn inbreds with a high level of resistance to fumonisin Production and accumulation in grain have not been identified. The objective Of this Study wits to evaluate a genetically diverse collection of inbreds as potential sources of resistance to fumonisin production and accumulation in grain and Fusarium car and kernel rot when crossed with a commercial "B73-type" line. F, hybrids developed with the inbred FR1064 and 1,589 and 1,030 inbreds were evaluated in inoculated and naturally infected trials, respectively, in 2000. Thirty-five F-1 hybrids with fumonisin concentration in grain of less than or equal to5 mug/g in both trials were selected. Inbreds from which these 35 F-1 hybrids were produced included yellow-, white-, and red-kernelled lines; flint and dent lines: and early- through late-maturing lines. fit 2001, low fumonisin concentration in grain and low ear rot severity were associated with several of the F-1 hybrids and their distinct F-2, and backcross to FR1064 generations. This suggests that several dominant genes are involved in resistance and that alleles for resistance from these inbreds can be transferred to FR1064.

Cleveland, T. E. and D. Bhatnagar (1986). "Characterization of Enzymes Involved in Aflatoxin-B1 Biosynthesis by Aspergillus-Parasiticus." Phytopathology 76(10): 1145-1145. ://A1986F034600695

Cleveland, T. E. and D. Bhatnagar (1987). "Individual Reaction Requirements of 2 Enzyme-Activities, Isolated from Aspergillus-Parasiticus, Which Together Catalyze Conversion of Sterigmatocystin to Aflatoxin-B1." Canadian Journal of Microbiology 33(12): 1108-1112. ://A1987M082900012

Cleveland, T. E. and D. Bhatnagar (1990). "Evidence for Denovo Synthesis of an Aflatoxin Pathway Methyltransferase near the Cessation of Active Growth and the Onset of Aflatoxin Biosynthesis in Aspergillus-Parasiticus Mycelia." Canadian Journal of Microbiology 36(1): 1-5. ://A1990CT87300001

Cleveland, T. E., D. Bhatnagar, et al. (1991). "Aflatoxin Production Via Cross-Feeding of Pathway Intermediates During Cofermentation of Aflatoxin Pathway-Blocked Aspergillus- Parasiticus Mutants." Applied and Environmental Microbiology 57(10): 2907-2911. ://A1991GH55800021 Cofermentation of Aspergillus parasiticus strains (SRRC 163 and SRRC 2043) blocked at different steps in the aflatoxin B1 (AFB1) biosynthetic pathway in a synthetic liquid medium or on seeds (cottonseed, corn kernels, and peanuts) resulted in production of AFB1. Strain SRRC 2043 accumulated O- methylsterigmatocystin (OMST), a late precursor in AFB1 biosynthesis, whereas SRRC 163 accumulated averantin, an early precursor in the pathway. Strain SRRC 2043 secreted large amounts of OMST in culture relative to the amounts of several other pathway intermediates secreted into media (by other AFB1 pathway-blocked strains). AFB1 production occurred even when colonies of SRRC 163 and SRRC 2043 strains (producing no detectable AFB1) were grown together on an agar medium while physically separated from each other by a filter membrane (0.22-mu-m pore size). In addition, when mycelia of strain SRRC 163 were added to culture filtrates (containing no mycelia but containing secreted OMST) of strain SRRC 2043, AFB1 production occurred. The results suggested a chemical (rather than genetic) mechanism of complementation for AFB1 production between AFB1 pathway-blocked strains, since no mycelial contact was required between these strains for AFB1 production. The mechanism for chemical complementation involves secretion of OMST by SRRC 2043 and subsequent absorption and conversion of OMST to AFB1 by mycelia of strain SRRC 163.

Cleveland, T. E., D. Bhatnagar, et al. (1987). "Conversion of a New Metabolite to Aflatoxin-B2 by Aspergillus- Parasiticus." Applied and Environmental Microbiology 53(12): 2804-2807. ://A1987L057500019

Cleveland, T. E., P. F. Dowd, et al. (2003). "United States Department of Agriculture - Agricultural Research Service research on pre-harvest prevention of mycotoxins and mycotoxigenic fungi in US crops." Pest Management Science 59(6-7): 629-642. ://000183400700007 Mycotoxins (ie toxins produced by molds) are fungal metabolites that can contaminate foods and feeds and cause toxic effects in higher organisms that consume the contaminated commodities. Therefore, mycotoxin contamination of foods and feeds results is a serious food safety issue and affects the competitiveness of US agriculture in both domestic and export markets. This article highlights research accomplished by Agricultural Research Service (ARS) laboratories on control of pre-harvest toxin contamination by using biocontrol, host-plant resistance enhancement and integrated management systems. Emphasis is placed on the most economically relevant mycotoxins, namely aflatoxins produced by Aspergillus flavus, Link, trichothecenes produced by various Fusarium spp and fumonisins produced by F verticillioides. Significant inroads have been made in establishing various control strategies such as development of atoxigenic biocontrol fungi that can outcompete their closely related, toxigenic cousins in field environments, thus reducing levels of mycotoxins in the crops. Potential biochemical and genetic resistance markers have been identified in crops, particularly in corn, which are being utilized as selectable markers in breeding for resistance to aflatoxin contamination. Prototypes of genetically engineered crops have been developed which: (1) contain genes for resistance to the phytotoxic effects of certain trichothecenes, thereby helping reduce fungal virulence, or (2) contain genes encoding fungal growth inhibitors for reducing fungal infection. Gene clusters housing the genes governing formation of trichothecenes, fumonisins and aflatoxins have been elucidated and are being targeted in strategies to interrupt the biosynthesis of these mycotoxins. Ultimately, a combination of strategies using biocompetitive fungi and enhancement of host-plant resistance may be needed to adequately prevent mycotoxin contamination in the field. To achieve this, plants may be developed that resist fungal infection and/or reduce the toxic effects of the mycotoxins themselves, or interrupt mycotoxin biosynthesis. This research effort could potentially save affected agricultural industries hundreds of millions of dollars during years of serious mycotoxin outbreaks.

Cleveland, T. E., A. R. Lax, et al. (1987). "Appearance of Enzyme-Activities Catalyzing Conversion of Sterigmatocystin to Aflatoxin-B1 in Late- Growth-Phase Aspergillus-Parasiticus Cultures." Applied and Environmental Microbiology 53(7): 1711-1713. ://A1987J039200057

Cotty, P. J. and D. Bhatnagar (1994). "Variability among Atoxigenic Aspergillus-Flavus Strains in Ability to Prevent Aflatoxin Contamination and Production of Aflatoxin Biosynthetic-Pathway Enzymes." Applied and Environmental Microbiology 60(7): 2248-2251. ://A1994NV57200006 and http://aem.asm.org/cgi/content/abstract/60/7/2248 Five strains of Aspergillus flavus lacking the ability to produce aflatoxins were examined in greenhouse tests for the ability to prevent a toxigenic strain from contaminating developing cottonseed with aflatoxins. All atoxigenic strains reduced contamination when inoculated into developing bells 24 h prior to the toxigenic strain. However, only one strain, AF36, was highly effective when inoculated simultaneously with the toxigenic strain. All five strains were able to inhibit aflatoxin production by the toxigenic strain in liquid fermentation. Thus, in vitro activity did not predict the ability of an atoxigenic strain to prevent contamination of developing bells. Therefore, strain selection for competitive exclusion to prevent aflatoxin contamination should include evaluation of efficacy in developing crops prior to field release. Atoxigenic strains were also characterized by the ability to convert several aflatoxin precursors into aflatoxin B-1. Four atoxigenic strains failed to convert any of the aflatoxin biosynthetic precursors to aflatoxins. However, the strain (AM6) most effective in preventing aflatoxin contamination in developing bells converted all tested precursors into aflatoxin B-1, indicating that this strain made enzymes in the aflatoxin biosynthetic pathway.

Cromey, M. G., S. C. Shorter, et al. (2002). "Cultivar and crop management influences on fusarium head blight and mycotoxins in spring wheat (Triticum aestivum) in New Zealand." New Zealand Journal of Crop and Horticultural Science 30(4): 235-247. ://000180614200003 Cultivar and crop management influences on fusarium head blight (FHB) of wheat (Triticum aestivum L.) were investigated in cultivar field trials and commercial wheat crops in the North Island of New Zealand over two growing seasons. There were consistent differences between cultivars in their susceptibility to FHB. The Chinese wheat 'Nanjing' had the lowest level of FHB, mycotoxins, and Fusarium infection in grain. Although no New Zealand cultivars approached an equivalent level of resistance, FHB in some cultivars was low in most situations, and these cultivars had a useful level of resistance. FHB and mycotoxin levels varied widely between crops surveyed. Two Fusarium mycotoxins, deoxynivalenol (DON) and nivalenol (NIV), were detected in grain samples from crops and trials. Overall, DON levels were higher than NIV in crops in both years. FHB incidence and levels of Fusarium infection and mycotoxins in grain were closely related in samples from a particular crop, but the relationships were much less apparent between crops. F. graminearum predominated in grain samples, although F. avenaceum, F. culmorum, and F. poae were also common. Highest levels of F. graminearum were recorded in grain samples from crops that followed maize, whereas F. avenaceum and F. poae were more common in samples from crops that did not follow maize.

Curtui, V., E. Usleber, et al. (1998). "A survey on the occurrence of mycotoxins in wheat and maize from western Romania." Mycopathologia 143(2): 97-103. ://000079327200006

Cvetnic, Z. (1994). "Cyclopiazonic Acid and Aflatoxin Production by Cultures of Aspergillus-Flavus Isolated from Dried Beans and Maize." Nahrung-Food 38(1): 21-25. ://A1994MY05700004

Danicke, S., S. Doll, et al. (2008). "On the evaluation of the occurrence of the Fusarium-toxins deoxynivalenol (DON), zearalenone (ZON) and their metabolites in physiological substrates of the pig." Tieraerztliche Praxis Ausgabe Grosstiere Nutztiere 36(1): 35-47. ://WOS:000257363700006 AND http://www.botanischergarten.ch/Bt/Danicke-Evaluation-Fumonisin-2008.pdf Objective:The analysis of blood and bile of the pig for residues of the Fusarium toxins deoxynivalenol (DON) and zearalenone (ZON) and their metabolites is often used for proving an exposure of pigs to these toxins. The evaluation of the clinical relevance of such results is discussed controversially in practice. Hence, the aim of the present review was to discuss all those factors which facilitate the interpretation of toxin residue results. Material and methods: In particular, the concentrations of DON and ZON in diets-with special consideration of critical concentrations and background contamination -were contrasted with the toxin residue concentrations in the physiological substrates. For this purpose, a number of dose-response studies including piglets, fattening pigs and gilts were evaluated. Aspects of the toxicokinetics and analytical methods were critically discussed with regard to the interpretation of the analytical results and the possibilities of the derivation of upper limits for DON and ZON in blood and bile. Conclusions: The analysis of the diets for both toxins often provides a better basis for the evaluation of the toxin exposure of the pigs if the diet can be assigned indisputably. Therefore, the feed analysis has a great prophylactic importance in monitoring the feed hygienic status for preventing of intoxications by ZON and DON. Clinical relevance: Positive results of DON and ZON in blood and bile have only a very limited relevance for the evaluation of a critical dietary exposure of pigs.

Dantzman, J. and L. Stoloff (1972). "Screening Method for Aflatoxin in Corn and Various Corn Products." Journal of the Association of Official Analytical Chemists 55(1): 139-&. ://WOS:A1972L502000036

Daradimos, E., P. Marcaki, et al. (2000). "Evaluation and validation of two fluorometric HPLC methods for the determination of aflatoxin B-1 in olive oil." Food Additives and Contaminants 17(1): 65-73. ://000086162900007 Two methods for the determination of aflatoxin B-1(AFB(1)) in olive oil were tested and compared. In method A the oil sample was mixed with methanol + water (60 + 40), extracted with hexane and then with chloroform. Chloroform was evaporated and the residue was dissolved with dichloromethane which was then transferred for clean-up onto a silica "Sep-Pak' cartridge. The cartridge was pre-washed with hexane, ethyl ether and dichloromethane. AFB(1) was eluted with chloroform + acetone (9+1), and evaporated to dryness. In method B, the oil sample was mixed with methanol + water (80+20), shaken and centrifuged. The supernatant was diluted 1:10 with water and 10 ml of the diluted mixture transferred to an "Aflaprep' immunoaffinity column for the clean-up step. AFB(1) was eluted with acetonitrile and evaporated to dryness. AFB(1) from both methods was derivatized to its hemiacetal (AFB(2a)) and then quantitated by HPLC using a C-18 (60 Angstrom 4.6 x 250 mm) column with fluorescence detection. Both methods are simple, reliable nd efficient, but method A showed a lower detection limit (2.8 ng/kg) than method B (56 ng/kg). With a 95% confidence level there was no significant difference in recovery between the two methods, which was 87.2% for method A and 84.8% for method B. In addition, application of a two- tailed F-test to the variances within spiked samples at concentrations 1, 2, 5 and 10 mu g/kg separately showed that there was no significant difference in the precisions of the two methods. Fifty samples of olive oil of Greek origin produced between 1995 and 1998 were examined with both methods for the presence of AFB(1). When analysing the samples wit method B, the presence of AFB(1) was not detected. The use of method A revealed the presence of AFB(1) in 72% of the samples. The range of contamination was generally found to ber very low (2.8-15.7 ng/kg), however one sample was contaminated with 46.3 ng/kg.

Dawlatana, M., R. D. Coker, et al. (2002). "The occurrence of mycotoxins in key commodities in Bangladesh: Surveillance results from 1993 to 1995." Journal of Natural Toxins 11(4): 379-386. ://000179853900014 A three-year surveillance program assessed the extent of mycotoxin contamination of key foods and feeds grown in Bangladesh. The study also included groundnuts utilized as snack food. In the first two phases of the program the samples collected were analyzed only for aflatoxins, but in the third phase, as well as for aflatoxins, samples were tested for the presence of fumonisin B-1, ochratoxin A, zearalenone, deoxynivalenol, and T-2 toxin. Of the foods and feeds tested, the incidence of aflatoxin contamination varied from low (rice collected from farmers' stores, 8%) to high (maize, 67%). However, both the average total aflatoxin contents (< 1.0 mug/kg) and the maximum aflatoxin B-1 contents (less than or equal to 5.0 mug/kg) recorded for pulses, rice and its various products, and wheat were low. On the other hand, the levels of contamination of maize, roasted and raw groundnuts, and poultry feed were considerably higher, with average total aflatoxin B-1 contents of 33, 13, 65, and 7 mug/kg, respectively, and maximum aflatoxin B-1 contents of 245, 79, 480, and 160 mug/kg, respectively. Fumonisin B-1, ochratoxin A, zearalenone, deoxynivalenol, and T-2 toxin were found, to any significant extent, only in some of the maize samples tested, always accompanied by aflatoxins. One sample of maize contained five mycotoxins, namely, the aflatoxins, fumonisin B-1, deoxynivalenol, zearalenone, and ochratoxin A. In a limited trial using hospital staff in Dhaka, the analysis of the aflatoxin-albumin adduct in serum showed that approximately half of the test group had been recently exposed to low levels of aflatoxins.

De Farias, A. X., C. F. Robbs, et al. (2000). "Endogenous Aspergillus spp. contamination of postharvest corn in Parana State, Brazil." Pesquisa Agropecuaria Brasileira 35(3): 617-621. ://000086754800018 Sixty post-harvested samples of maize kernels from three regions of the Parana State, Brazil, were evaluated concerning endogenous fungi contamination and toxigenic potential of Aspergillus spp. and some of their teleomorfs. Forty apparently healthy kernels were selected from each sample, disinfested with NaClO and incubated at 25+/-1 degrees C for fungal growth. Fungus species were isolated in Czapek-Dox agar plates. The species Aspergillus flavus, A. parasiticus, Eurotium amstelodami and E. chevalieri were identified. The toxigenic potential of Aspergillus species were analyzed in coconut agar medium. Eurotium spp. were evaluated for their metabolics in peanut agar medium and in wheat grits. The kernel contamination varied from 0 to 100% and the prevalent genera detected were Aspergillus, Penicillium and Fusarium. A. flavus was the predominant species (64%), followed by E. amstelodami (19%), E. chevalieri (10%) and A. parasiticus (7%). From 109 A. flavus species isolated, 73 strains synthesized aflatoxins B-1 and B- 2, 20 synthesized B-1, seven synthesized B-1 and G(1), three synthesized B-1, B-2 and G(1) and in six strains aflatoxin production was not detected. All A. parasiticus species produced, simultaneously, B-1, B-2, G(1) and G(2). Sterigmatocystin synthesis was not detected in any condition by E. amstelodami and E. chevalieri. de la Campa, R., D. C. Hooker, et al. (2005). "Modeling effects of environment, insect damage, and Bt genotypes on fumonisin accumulation in maize in Argentina and the Philippines." Mycopathologia 159(4): 539-552. ://000230141800009 AND http://www.botanischergarten.ch/Bt/delaCampa-Modeling-Effects-Fumonisin-2005.pdf Fumonisins are common contaminants of maize (Zea mays L.) grain products, especially in countries where maize is a major constituent of the diet and are harmful to human and animal health. There is a need to better de. ne environmental conditions that favor fumonisin accumulation in the grain of maize. The impacts of biotic and abiotic factors, and hybrids containing the Cry1Ab protein from Bacillus thuringiensis (Bt), were associated with fumonisin accumulation in the grain of maize across contrasting environments in Argentina and the Philippines between 2000 and 2002. Average fumonisin concentrations in grain samples varied from 0.5 to 12 mu g g(-1) across field locations in Argentina, and from 0.3 to 1.8 mu g g(-1) across locations in the Philippines. The ratio of fumonisin B1 to fumonisin B2 was < 3.0 in four of nine locations in Argentina, which proved to be due to a higher prevalence of Fusarium proliferatum in those locations. Most of the variability of total fumonisins among maize grain samples was explained by location or weather (47%), followed by insect damage severity in mature ears (17%), hybrid (14%), and with the use of Bt hybrids (11%). In Argentina, where conditions were more favorable for accumulation of fumonisin in the years considered, fumonisin concentrations were lower in Bt hybrids compared to their genetic isolines by an average of 40%. A model was developed to predict fumonisin concentration using insect damage to ears and weather variables as predictors in the model. Four periods of weather around silking were identified as critical for fumonisin concentrations at harvest. The model accounted for 82% of the variability of total fumonisin across all locations in 2 years of the study. de Nijs, M., E. A. Sizoo, et al. (1998). "Fumonisin B-1 in maize for food production imported in The Netherlands." Food Additives and Contaminants 15(4): 389-392. ://WOS:000073683300003 AND http://www.botanischergarten.ch/Bt/de-Nijs-Fumonisin-B1-Maize-1998.pdf Sixty-two samples of maize imported in The Netherlands and intended for human consumption were screened for the presence and concentration of fumonisin B-1. Sixty-one of those samples contained fumonisin B-1 with concentrations ranging from 30 to 3350 mu g kg(-1), 11 maize samples contained > 1000 mu g kg(-1). The average fumonisin Br concentration was 640 mu g kg(-1) for the positive samples and 620 mu g kg(-1) for all samples. Medians were 600 mu g kg(-1) and 550 mu g kg(-1) for positive and all samples, respectively. The results obtained were comparable to results from other studies in maize from various countries. de Nijs, M., E. A. Sizoo, et al. (1998). "The occurrence of fumonisin B-1 in maize-containing foods in The Netherlands." Food Additives and Contaminants 15(4): 385-388. ://WOS:000073683300002 AND http://www.botanischergarten.ch/Bt/de-Nijs-Occurrence-Fumonisin-NL-1998.pdf Seventy-eight maize-containing foods obtained from retail stores in The Netherlands were analysed for fumonisin B-1 contamination Thirty-six per cent of the samples were contaminated with fumonisin Br in the range of 8 mu g/kg(-1) (limit of detection) to 1430 mu g/kg(-1). Forty-six per cent of the minimally treated maize samples (n = 39; maize for bread production, maize for popcorn, maize flour and polenta) were contaminated with fumonisin Br in the range of 8-380 mu g kg(-1). Twenty-six per cent of the maize- containing processed foods (n = 39; tostada, canned maize, maize starch, maize bread, popped maize, flour mixes, maize chips and cornflakes) were contaminated with fumonisin B-1 in the range of 8-1430 mu g/kg(-1). This survey shows that maize-containing foods in The Netherlands frequently can be contaminated with fumonisin B-1. de Nijs, M., H. P. van Egmond, et al. (1998). "Assessment of human exposure to fumonisin B-1." Journal of Food Protection 61(7): 879-884. ://000074877900021 AND http://www.botanischergarten.ch/Bt/Nijs-AssessmentHuman-Fumonisin-1998.pdf

Deleon, C., C. Kitbamroong, et al. (1995). "Selection for Resistance to Aflatoxin Formation in Maize through Seed Inoculation." Food Additives and Contaminants 12(3): 491-495. ://A1995RC65700030

Desai, M. R. and S. K. Ghosh (2003). "Aflatoxin related occupational exposure to maize processing workers." Cellular and Molecular Biology 49(4): 529-535. ://000184379300011 A study was undertaken on environmental mycoflora of a maize processing industry in Ahmedabad. The airborne fungal communities were isolated and identified both qualitatively by Petri-plate exposure method and quantitatively by using Andersen-6- stage viable sampler, Midget impinger and high volume samples (cone and Hexhlet for total and respirable dusts, respectively). Of all the isolates genus Aspergillus was the dominant environmental mycoflora and among all the species of Aspergillus A. flavus was the common isolates irrespective of the method applied for sample collection. Maximum number of isolates were recovered from Elevator department. From total and respirable dusts, about 56.6% and 44.4% of recovery accounted for genus Aspergillus alone. Total percentages of aflatoxin positive strains of A. flavus were 5.65% and 9.73% from total and respirable dusts, respectively. These toxigenic strains were identified on various media like CZ with 0.05% anisaldehyde, APA and CAM. Surface morphology of toxigenic strains and dust samples were carried out using SEM.

Desjardins, A. E. (2003). "Gibberella from A (venaceae) to Z (eae)." Annual Review of Phytopathology 41: 177-198. ://000186493900009 Gibberella species are destructive plant pathogens, although many are more familiar under their Fusarium anamorph names. The recent synthesis of phylogenetic, biological, and morphological species approaches has revitalized taxonomy of a genus that was first described almost 200 years ago. Twelve sexual species of Gibberella of agricultural importance were selected for this review to represent phylogenetic, biological, and chemical diversity of the genus. Even closely related Gibberella species can differ in reproductive mode, geographic and host distribution, plant pathogenesis, and production of toxins and other biologically active metabolites. Gibberella species have proven amenable to meiotic and molecular genetic analysis; A complete genome sequence of G. zeae should soon be available. Combining gene disruption strategies with new genomics technologies for expression profiling should help plant pathologists to understand the pathological and evolutionary significance of biological and chemical diversity in Gibberella and to identify novel strategies for disease control.

Desjardins, A. E., G. Manandhar, et al. (2000). "Occurrence of Fusarium species and mycotoxins in nepalese maize and wheat and the effect of traditional processing methods on mycotoxin levels." Journal of Agricultural and Food Chemistry 48(4): 1377-1383. ://000086572200067 Maize (Zea mays) and wheat (Triticum aestivum) collected in the foothills of the Nepal Himalaya Mountains were analyzed for Fusarium species and mycotoxins: fumonisins, nivalenol (NIV), and deoxynivalenol (DON). Predominant species were Gibberella fujikuroi mating population A (F. moniliforme) in maize and F. graminearum in maize and wheat; G. fujikuroi mating population D (F. proliferatum), F. acuminatum, Ij: avenaceum, F. chlamydosporum, F. equiseti, F. oxysporum, F. semitectum, and F. torulosum were also present. Strains of G. fujikuroi mating population A produced fumonisins, and strains of F. graminearum produced NIV or DON. By immunoassay or highperformance liquid chromatography, fumonisins were > 1000 ng/g in 22% of 74 maize samples. By immunoassay or fluorometry, NIV and DON were,1000 ng/g in 16% of maize samples but were not detected in wheat. Fumonisins and DON were not eliminated by traditional fermentation for producing maize beer, but Nepalese rural and urban women were able to detoxify contaminated maize by hand- sorting visibly diseased kernels.

Desjardins, A. E., H. K. Manandhar, et al. (2000). "Fusarium species from Nepalese rice and production of mycotoxins and gibberellic acid by selected species." Applied and Environmental Microbiology 66(3): 1020-1025. ://000085604800022 Infection of cereal grains with Fusarium species can cause contamination with mycotoxins that affect human and animal health. To determine the potential for mycotoxin contamination, we isolated Fusarium species from samples of rice seeds that were collected in 1997 on farms in the foothills of the Nepal Himalaya, The predominant Fusarium species in surface- disinfested seeds with husks were species of the Gibberella fujikuroi complex, including G, fujikuroi mating population A (anamorph, Fusarium verticillioides), G. fujikuroi mating population C (anamorph, Fusarium fujikuroi), and G, fujikuroi mating population D (anamorph, Fusarium proliferatum). The widespread occurrence of mating population D suggests that its role in the complex symptoms of bakanae disease of rice may be significant. Other common species were Gibberella zeae (ana morph, Fusarium graminearum) and Fusarium semitectum, with Fusarium acuminatum. Fusarium anguioides, Fusarium avenaceum, Fusarium chlamydosporum, Fusarium equiseti, and Fusarium oxysporum occasionally present. Strains of mating population C produced beauvericin, moniliformin, and gibberellic acid, but little or no fumonisin, whereas strains of mating population D produced beauvericin, fumonisin, and, usually, moniliformin, but no gibberellic acid. Some strains of G, zeae produced the 8-ketotrichothecene nivalenol, whereas others produced deoxynivalenol. Despite the occurrence of fumonisin-producing strains of mating population D, and of 8-ketotrichothecene- producing strains of G, zeae, Nepalese rice show-ed no detectable contamination with these mycotoxins. Effective traditional practices for grain drying and storage may prevent contamination of Nepalese rice with Fusarium mycotoxins.

Desjardins, A. E., G. P. Munkvold, et al. (2002). "FUM1 - A gene required for fumonisin biosynthesis but not for maize ear rot and ear infection by Gibberella moniliformis in field tests." Molecular Plant-Microbe Interactions 15(11): 1157-1164. ://000178783600007 We have analyzed the role of fumonisins in infection of maize (Zea mays) by Gibberella moniliformis (anamorph Fusarium verticilloides) in field tests in Illinois and Iowa, United States. Fumonisin-nonproducing mutants were obtained by disrupting FUM1 (previously FUM5), the gene encoding a polyketide synthase required for fumonisin biosynthesis. Maize car rot, ear infection, and fumonisin contamination were assessed by silk-channel injection in 1999 and 2000 and also by spray application onto maize silks, injection into maize stalks, and application with maize seeds at planting in 1999. Ear rot was evaluated by visual assessment of whole ears and by calculating percentage of symptomatic kernels by weight. Fumonisin levels in kernels were determined by high- performance liquid chromatography. The presence of applied strains in kernels was determined by analysis of recovered isolates for genetic markers and fumonisin production. Two independent fumonisin-nonproducing (fum1-3 and fum1-4) mutants were similar to their respective fumonisin-producing (FUM1-1) progenitor strains in ability to cause ear rot following silk-channel injection and also were similar in ability to infect maize ears following application by all four methods tested. This evidence confirms that fumonisins are not required for G. moniliformis to cause maize ear rot and ear infection.

Desjardins, A. E. and R. D. Plattner (2000). "Fumonisin B-1-nonproducing strains of Fusarium verticillioides cause maize (Zea mays) ear infection and ear rot." Journal of Agricultural and Food Chemistry 48(11): 5773-5780. ://000165490000111and http://www.botanischergarten.ch/Mycotoxins/Desjardins-Fumonisin-Maiz.pdf Fumonisins are polyketide mycotoxins produced by Fusarium verticillioides (synonym F. moniliforme), a major pathogen of maize (Zea mays) worldwide. Most field strains produce high levels of fumonisin B-1 (FB1) and low levels of the less- oxygenated homologues FB2 and FB3, but fumonisin B-1- nonproducing field strains have been obtained by natural variation. To test the role of various fumonisins in pathogenesis on maize under field conditions, one strain producing FB1, FB2, and FB3, one strain producing only FB2, one strain producing only FB3, and one fumonisin-nonproducing strain were applied to ears via the silk channel and on seeds at planting. Disease severity on the harvested ears was evaluated by visible symptoms and by weight percent symptomatic kernels. Fumonisin levels in kernels were determined by high- performance liquid chromatography. The presence of the applied FB1- nonproducing strains in kernels was determined by analysis of recovered strains for fumonisin production and other traits. All three FB1-nonproducing strains were able to infect ears following either silk-channel application or seed application at planting and were as effective as the FB1-producing strain in causing ear rot following silk-channel application. These results indicate that production of FB1, FB2, or FB3 is not required for F. verticillioides to cause maize ear infection and ear rot.

Desjardins, A. E., R. D. Plattner, et al. (2000). "Gibberella fujikuroi mating population A and Fusarium subglutinans from teosinte species and maize from Mexico and Central America." Mycological Research 104: 865-872. ://000088847400018 Seed samples of maize (Zen mays ssp. mays) from Mexico and of teosintes (Zea spp.), the nearest wild relatives of maize, from Mexico, Guatemala, and Nicaragua were assessed for infection with Fusarium species. Strains similar in morphology to Fusarium moniliforme and F. subglutinans were the most frequent isolates from maize and from teosinte species including Z. diploperennis, Z. luxurians, Z. mays ssp. mexicana, and Z. mays ssp. parviglumis. Analysis of fertility, vegetative compatibility and mycotoxin production identified 63% of the 70 F. moniliforme strains from teosinte as genetically diverse members of Gibberella fujikuroi mating population A, a common pathogen of maize. The F. subglutinans strains from maize and teosinte were similarly genetically diverse, but were not fertile with standard testers of G. fujikuroi mating populations B and E, common pathogens of Poaceae, or of mating population H, which causes pitch canker disease of pine. Fifty- four percent of the 80 F. subglutinans strains were fertile when crossed with female tester strains from teosinte and maize collected in a field at Netzahualcoyotyl in the state of Mexico. These strains from Mexico and Central America may comprise a new and distinct G. fujikuroi mating population, but a strain from the Netzahualcoyotyl field site was fertile with a strain of G. fujikuroi mating population H from California. Thus, F. subglutinans from teosinte and maize may have a close relationship to mating population H from pine.

Desjardins, A. E., R. D. Plattner, et al. (1998). "Distribution of fumonisins in maize ears infected with strains of Fusarium moniliforme that differ in fumonisin production." Plant Disease 82(8): 953-958. ://000074931700024 Strains of Fusarium moniliforme (Gibberella fujikuroi mating population A) that differ in fumonisin production in vitro were previously identified in a Kansas field population. One strain that produced high levels of fumonisins and two strains that produced very low levels of fumonisins were applied to maize kernels at planting at the Rocky Ford Farm near Manhattan, Kansas. The distribution of fumonisins in symptomatic and symptomless kernels from individual harvested ears was determined by high performance liquid chromatography, and the distribution of the three applied strains in the kernels was determined by vegetative compatibility group analysis. Both symptomatic and symptomless kernels were extensively colonized with F. moniliforme, but the highest levels of fumonisins were in the symptomatic kernels. All three applied strains were recovered from kernels in 1993, and two of them were recovered from kernels in 1994. However, a high frequency of ear and kernel infection with a strain that produced little fumonisin in vitro did not consistently decrease the level of fumonisins. The frequency of infection with fumonisin low- producing strains may have been too low for competitive exclusion of naturally occurring fumonisin high-producing strains. Also, strains that are low-fumonisin producers under laboratory conditions may be high producers in the field.

Desjardins, A. E., R. D. Plattner, et al. (1995). "Genetic-Analysis of Fumonisin Production and Virulence of Gibberella-Fujikuroi Mating Population a (Fusarium-Moniliforme) on Maize (Zea-Mays) Seedlings." Applied and Environmental Microbiology 61(1): 79-86. ://A1995PY86700014 The phytopathogenic fungus Gibberella fujikuroi mating population A (anamorph, Fusarium moniliforme) produces fumonisins, which are toxic to a wide range of plant and animal species. Previous studies of field strains have identified a genetic locus, designated fum1, that can determine whether fumonisins are produced. To test the relationship between fumonisin production and virulence on maize seedlings, a cross between a fum1(+) held strain that had a high degree of virulence and a fum1(-) field strain that had a low degree of virulence was made, and ascospore progeny were scored for these traits. Although a range of virulence levels was recovered among the progeny, high levels of virulence were associated with production of fumonisins, and highly virulent, fumonisin- nonproducing progeny were not obtained. A survey of field strains did identify a rare fumonisin-nonproducing strain that was quite high in virulence. Also, the addition of purified fumonisin B-1 to virulence assays did hot replicate all of the seedling blight symptoms obtained with autoclaved culture material containing fumonisin. These results support the hypothesis that fumonisin plays a role in virulence but also indicate that fumonisin production is not necessary or sufficient for virulence on maize seedlings.

Desjardins, A. E., R. D. Plattner, et al. (1994). "Fumonisin Production and Other Traits of Fusarium-Moniliforme Strains from Maize in Northeast Mexico." Applied and Environmental Microbiology 60(5): 1695-1697. ://A1994NJ57700049 Strains of Fusarium moniliforme from maize seed collected in four fields in northeast Mexico were tested for fumonisin production in culture, for sexual compatibility, and for vegetative compatibility by using non-nitrate-utilizing mutants. The test results indicate that a diverse population of fumonisin-producing strains off. moniliforme (Gibberella fujikuroi) mating population A predominates and that a potential exists for production of fumonisins in Mexican maize.

Desjardins, A. E., R. D. Plattner, et al. (1997). "Production of fumonisin B-1 and moniliformin by Gibberella fujikuroi from rice from various geographic areas." Applied and Environmental Microbiology 63(5): 1838-1842. ://A1997WX36100031 Gibberella fujikuroi strains isolated from rice in the United States, Asia, and other geographic areas mere tested for sexual fertility with members of mating population D and for production of fumonisin B-1 and moniliformin in culture. Of the 59 field strains tested, 32 (54%) were able to cross with tester strains of mating population D, but only a few ascospores were produced in most of these crosses, Thirty-four strains produced more than 10 mu g of fumonisin B-1 per g, hut only three strains produced more than 1000 mu g/g. Twenty-five strains produced more than 100 mu g of moniliformin per g, and 15 produced more than 1,000 mu g/g. Seven held strains produced both fumonisin B-1 and moniliformin, but none of these strains produced a high level of fumonisin B-1 (>1,000 mu g/g). However, a genetic cross between a strain that produced fumonisin B, but no moniliformin and a strain that produced moniliformin but no fumonisin B-1 yielded progeny that produced high levels of both toxins, Strains of G. fujikuroi isolated from rice infected with bakanae disease are similar to strains of mating population D isolated from maize in their ability to produce both fumonisins and moniliformin, This finding suggests a potential for contamination of rice with both fumonisins and moniliformin.

Desjardins, A. E., R. D. Plattner, et al. (1995). "Genetic and Biochemical Aspects of Fumonisin Production." Abstracts of Papers of the American Chemical Society 209: 108-AGFD. ://A1995QP23200108

Desjardins, A. E., R. D. Plattner, et al. (1996). "Linkage among genes responsible for fumonisin biosynthesis in Gibberella fujikuroi mating population A." Applied and Environmental Microbiology 62(7): 2571-2576. ://A1996UV79200056 Most naturally occurring strains of the fungus Gibberella fujikuroi mating population A produce high levels of tbe mycotoxin fumonisin B-1 (FB1), which is oxygenated at both carbons C-5 and C-10. Some strains, however, produce only FB2 or FB3, suggesting that they lack the ability to hydroxylate position C-10 or C-5, respectively. Genetic analysis indicates that these different phenotypes are due to single gene defects at closely linked loci designated fum2 and fum3. Further allelism tests indicate that both fum2 and fum3 are closely linked to fum1, a previously identified gene that regulates fumonisin production. The recovery frequency of FB1- producing progeny from cross 510 between fum1 and fum2 mutations suggests a map distance of approximately 6.2 cM between these two loci. Amplified fragment length polymorphism analysis of parents and progeny of cross 510 was employed to confirm that the FB1- producing strains are recombinant progeny. We conclude that fum1, fum2, and fum3 constitute a fumonisin biosynthetic gene cluster on chromosome 1 of the restriction fragment length-map of G. fujikuroi.

Desjardins, A. E., R. D. Plattner, et al. (1992). "Heritability of Fumonisin-B1 Production in Gibberella-Fujikuroi Mating Population-A." Applied and Environmental Microbiology 58(9): 2799-2805. ://A1992JL63200014 Fumonisins are mycotoxins produced by strains belonging to several different mating populations of Gibberella fujikuroi (anamorphs, Fusarium section Liseola), a major pathogen of maize and sorghum worldwide. We studied the heritability of fumonisin production in mating population A by crossing fumonisin-producing strains collected from maize and sorghum in the United States with fumonisin-nonproducing strains collected from maize in Nepal. Random ascospore and tetrad progeny from three of these crosses were analyzed by gas chromatography-mass spectrometry and high-performance liquid chromatography for their ability to produce fumonisins on autoclaved cracked maize. In all three crosses, the ability to produce fumonisins, predominately fumonisin B1, segregated as a single gene or group of closely linked genes. Intercrosses between appropriate progeny and parents were poorly fertile, so we could not determine if the apparent single genes that were segregating in each of these crosses were allelic with one another. Mating type and spore-killer traits were scored in some crosses, and each segregated, as expected, as a single gene that was unlinked to the ability to produce fumonisins. We conclude that G. fujikuroi mating population A provides a powerful genetic system for the study of this important fungal toxin.

Deutz, A., A. Klauber, et al. (2000). "Examination of deer feed samples for the mycotoxins deoxynivalenol and zearalenon." Zeitschrift Fur Jagdwissenschaft 46(4): 279-283. ://000166145000005 Potential effects of mycotoxins on the health of roe deer were discussed on the basis of an examination of 20 deer feed samples for the mycotoxins deoxynivalenol and zearalenon. Feed rations containing a high percentage of maize showed significantly higher mycotoxin concentrations. The feeding of rations containing a high percentage of maize may result in an increased risk of acute and chronical rumen acidoses and mycotoxicoses with the possibility of mutual negative effects. An additional bacteriological examination of the feed samples for Salmonella produced negative results.

Di, R., A. Blechl, et al. (2010). "Expression of a truncated form of yeast ribosomal protein L3 in transgenic wheat improves resistance to Fusarium head blight." Plant Science 178(4): 374-380. ://WOS:000276338700005 Fusarium head blight (FHB) is a disease that causes major economic losses in wheat and barley production worldwide. Contamination of food with the trichothecene mycotoxin deoxynivalenol (DON) produced by Fusarium is a major health concern for humans and animals because trichothecenes are potent cytotoxins of eukaryotic cells. Trichothecene mycotoxins inhibit translation by targeting ribosomal protein L3 at the peptidyltransferase center. We previously showed that expression of an N-terminal fragment of yeast L3 (L3 Delta) in transgenic tobacco plants reduced the toxicity of DON. Here, we produced transgenic wheat plants that express the same yeast 13 (L3 Delta) fragment and evaluated their susceptibility to Fusarium graminearum infection and their ability to accumulate DON. Following F. graminearum infection in greenhouse tests, two transgenic wheat lines expressing the highest levels of L3 Delta showed reductions in disease severity and kernel DON levels, compared to non-transformed plants. In a field test, a transgenic wheat line with the highest L3 Delta expression controlled by the maize Ubi1 promoter had significant reductions in visually scabby kernels and kernel DON levels. These results demonstrate that expression of a modified form of the ribosomal protein that is the target of DON can improve FHB resistance in wheat. (C) 2010 Elsevier Ireland Ltd. All rights reserved.

Dilkin, P., C. A. Mallmann, et al. (2002). "Production of fumonisins by strains of Fusarium moniliforme according to temperature, moisture and growth period." Brazilian Journal of Microbiology 33(2): 111-118. ://000184236400003 Production of fumonisins B-1 (FB1) and B-2 (FB2) by two Brasilian strains (LAMIC 2999/96 and 113F) and one American strain (NRRL 13616) of Fusarium moniliforme were evaluated in laboratory cultures subjected to different temperatures (20, 25, and 30degreesC), and moisture contents (25, 34, and 42%) on corn substrate. The cultures were grown during 10, 20, 30,45, and 60 days, totalizing 135 treatments with two repetitions for each one. The fumonisins were extracted with acetonitrile/water. The clean-up with end-capped C-18 silica (C-18ec) cartridges and fumonisin derivatization with o- phtaldialdeyde were carried out through an automated sample processor system (ASPEC), followed by quantification of the toxins through HPLC. Fumonisin production varied widely, reaching average yields from 0.25 to 55 15.45 mug/g of FB1 and from 0.15 to 3032.10 mug/g of FB2. In the present work, the factors strain, temperature, moisture and days of fungal culture were evaluated, and all of them had a bearing on the amounts of fumonisins produced. The highest FB1 average yields were obtained by the strain 113F, under the following conditions: 34% moisture content, 60 culture days, and temperature of 25degreesC. The highest FB2 average yield was obtained by the same strain with cultures over 45 days, 42% moisture content, at the temperature of 25degreesC. Via regression analysis, the ideal temperature for fumonisins production was, calculated as 24.5 and 24.3degreesC (+/- 2degreesC) for FB1 and FB2, respectively.

D'Mello, J. P. F., A. M. C. Macdonald, et al. (1998). "Pesticide use and mycotoxin production in Fusarium and Aspergillus phytopathogens." European Journal of Plant Pathology 104(8): 741-751. ://000078775900001 AND http://www.botanischergarten.ch/Bt/D'Mello-Pesticide-use-Mycotoxins-1998.pdf The major mycotoxigenic species of Fusarium and Aspergillus phytopathogens have been identified in this review. Since fungicides are widely used to control crop diseases caused by these fungi, it is pertinent to assess efficacy with respect to mycotoxin production. In both laboratory studies with pure cultures of phytopathogens and field trials with crop plants, the overall evidence concerning the effectiveness of fungicides is contradictory and in certain cases somewhat unexpected. In particular, at sub-lethal doses of a number of fungicides including carbendazim, tridemorph, difenoconazole and tebuconazole with triadimenol, mycotoxin production from Fusarium phytopathogens may increase. Furthermore, the efficacy of propiconazole and thiabendazole in the control of deoxynivalenol production from F. graminearum is not consistent. Evidence has been presented to suggest, for the first time, that fungicide-resistance in F. culmorum may be accompanied by a more persistent pattern of mycotoxin production. The limited evidence on the effects of fungicides on mycotoxin production in Aspergillus species is also conflicting. Under laboratory conditions, miconazole and fenpropimorph have been shown to increase aflatoxin production from A. parasiticus. Moreover, fenpropimorph increased production of the more toxic aflatoxin B1. Since fungal infection of plant products is often preceded by insect damage, there is interest in the effectiveness of insecticides to reduce infestation, infection and mycotoxin contamination. Additionally, insecticides may be effective in their own right, causing a direct effect on mycotoxin synthesis. The bulk of the evidence relates to effects on aflatoxin (AF) components B1; B2;G1 and G2. Under laboratory conditions, AFB1 production was most resistant to inhibition by insecticides, followed by AFG1, AFG2 and AFB2. This pattern of inhibition was particularly consistent for the organophosphorus insecticides. In one field study, Bux and carbaryl were considerably more effective than naled in reducing AFB1 contamination of maize kernels. It is concluded that if pesticide control is to be more effective in the future, additional criteria may be required in developing evaluation protocols for candidate compounds. In particular, the issue of fungicide-resistance in relation to mycotoxin production needs to be addressed in a concerted programme of research. Additionally, the potential of breeding and selecting cultivars resistant to disease caused by toxigenic fungi needs to be exploited in a parallel search for an environmentally acceptable solution to the question of mycotoxin contamination of plant products.

D'Mello, J. P. F., C. M. Placinta, et al. (1999). "Fusarium mycotoxins: a review of global implications for animal health, welfare and productivity." Animal Feed Science and Technology 80(3-4): 183-205. ://000082671200002 AND http://www.botanischergarten.ch/Bt/D'Mello-Fusarium-Mycotoxins-1999.pdf Trichothecenes, zearalenone (ZEN) and fumonisins are the major Fusarium mycotoxins occurring on a worldwide basis in cereal grains, animal feeds and forages. Other important Fusarium mycotoxins include moniliformin and fusaric acid. Spontaneous outbreaks of Fusarium mycotoxicoses have been recorded in Europe, Asia, New Zealand and South America and, in addition, chronic exposure occurs on a regular and more widespread scale. The metabolism and adverse effects of the Fusarium mycotoxins are considered in this review with particular reference to recent data on specific and proposed syndromes and to interactions among co- occurring mycotoxins. Within the trichothecene group, deoxynivalenol (DON) is associated with emesis, feed refusal and depressed feed intake in pigs, while T-2 toxin and diacetoxyscirpenol (DAS) are now clearly linked with oral lesions in poultry. The gut microflora of farm livestock are able to transform DON to a de-epoxy derivative. In contrast, the ovine metabolism of ZEN results in the production of five metabolites and relatively high levels of these forms may be excreted in the urine as glucuronides. There is now undisputed evidence that ZEN and its metabolites possess estrogenic activity in pigs, cattle and sheep, but T-2 toxin has also been implicated in reproductive disorders in farm livestock. Fumonisins are positively linked with pulmonary edema in pigs, leukoencephalomalacia in equines and with deranged sphingolipid metabolism in these animals. Fusarium mycotoxins have also been provisionally implicated in ovine ill-thrift, acute mortality of poultry and in duodenitis/proximal jejunitis of horses. Several Fusarium mycotoxins may co-occur in a particular feed ingredient or in compound feedingstuffs. In general, combinations of Fusarium mycotoxins result in additive effects, but synergistic and/or potentiating interactions have been observed and are of greater concern in livestock health and productivity. Synergistic effects have been reported between DON and fusaric acid; DON and fumonisin B-1 (FB1); and DAS and the Aspergillus-derived aflatoxins. Limited evidence of potentiation between FB1 and DON or T-2 toxin has also emerged recently Additive and synergistic effects between known and unidentified mycotoxins may account for enhanced adverse effects observed on feeding Fusarium-contaminated diets. The potential for transmission of DON into eggs and of ZEN into porcine kidney and liver has been demonstrated. However, lactational carry-over of FB1 appears not to occur, at least in cows and sows. It is concluded that livestock health, welfare and productivity may be severely compromised by consumption of DON, T-2 toxin, DAS, ZEN and fumonisins and by interactions among these mycotoxins. Safety of some animal products may also be at risk. Furthermore, in view of the limited options available for remediation, it is concluded that exploitation of crops resistant to Fusarium infection offers the most viable strategy for reducing mycotoxin contamination of grain and animal feed. (C) 1999 Elsevier Science B.V. All rights reserved.

Doko, M. B., C. Canet, et al. (1996). "Natural co-occurrence of fumonisins and zearalenone in cereals and cereal-based foods from Eastern and Southern Africa." Journal of Agricultural and Food Chemistry 44(10): 3240-3243. ://A1996VN64400060 The natural co-occurrence of fumonisin B1 (FB1), fumonisin B2 (FB2), fumonisin B3 (FB3), and zearalenone was investigated in 40 randomly selected cereals and cereal-based commodities collected in 1994 from Botswana, Kenya, Malawi, Mozambique, South Africa, Tanzania, Uganda, Zambia, and Zimbabwe. FB1 was detected in 37 of the samples (92.5%) at concentrations ranging from 20 to 1910 ng/g, while total fumonisin (FB1 + FB2 + FB3) concentrations in the same samples ranged from 20 to 2735 ng/g. The highest total fumonisin levels were detected in maize kernels from Zimbabwe (2735 ng/g). In contrast to the high incidence of fumonisins (92.5%), zearalenone was detected in only five samples (12.5%) at concentrations ranging from 40 to 400 ng/g. Linear regression analysis showed no correlation between the occurrence of fumonisins and zearalenone in the samples tested. Although limited in sample numbers, this survey ranks the fumonisins as major contaminants of cereals and cereal-based foods in Eastern and Southern Africa.

Doko, M. B., S. Rapior, et al. (1995). "Incidence and Levels of Fumonisin Contamination in Maize Genotypes Grown in Europe and Africa." Journal of Agricultural and Food Chemistry 43(2): 429-434. ://A1995QH79700032 The natural occurrence of fumonisin B-1 (FB1) and fumonisin B-2 (FB2) has been investigated in 26 maize inbred lines grown in Italy and in 72 maize hybrids grown in Croatia (19), Poland (7), Portugal (9), Romania (6), Benin (9), and Zambia (20). The incidence and levels of fumonisin contamination resulted in two major groups of countries. The first with high contamination included Italy, Portugal, Zambia, and Benin, with incidence of 100, 100, 100, and 82%, and fumonisin (FB1 + FB2) levels up to 2850, 4450, 1710, and 3310 ng/g, respectively. The second group, including Croatia, Poland, and Romania, showed very low levels of contamination (less than or equal to 70 ng/g) with 50% incidence of positive samples. A general trend for higher contamination levels was observed in maize genotypes with higher FAO maturity class or dent-type endosperm. Although the environmental conditions of the specific area of cultivation seem to play a role in the formation of fumonisin in maize, further investigations are needed to thoroughly establish the genotype-area-season interaction.

Doko, M. B. and A. Visconti (1994). "Occurrence of Fumonisins-B(1) and Fumonisin-B(2) in Corn and Corn-Based Human Foodstuffs in Italy." Food Additives and Contaminants 11(4): 433-439. ://A1994PA73700003

Doll, S., H. Valenta, et al. (2002). "Fusarium mycotoxins in conventionally and organically grown grain from Thuringia/Germany." Landbauforschung Volkenrode 52(2): 91-96. ://WOS:000177138700005 The fusarium mycotoxins deoxynivalenol (DON) and zearalenone (ZON) were determined in conventionally and organically grown grain harvested in 1998 in Thuringia/Germany. A total of 196 wheat samples and 69 rye samples was analysed. DON concentrations of conventionally grown wheat were found to be significantly higher than in organically grown wheat. Of conventionally grown wheat, 69% tested positive, containing a mean concentration of 1540 mug/kg dry matter (DM). In 54% of the organically grown wheat samples DON was detected with a mean value of 760 mug/kg DM. DON concentration in rye and ZON concentration in wheat showed similar tendencies. The different cultivars of conventionally grown wheat showed large differences in DON contamination. In the year of investigation, high concentrations of fusarium mycotoxins were typical in grain grown in Germany, such as the DON concentrations found here. ZON contamination of the Investigated samples was rather low, probably due to the early harvest before the heavy rainfalls in September. If the analysed wheat were to be included in a feed ration for pigs at 50%, the DON concentrations of 12% (respectively 4%) in the rations mixed with conventionally grown wheat (respectively organically grown wheat) would exceed the orientation value for critical concentrations in feedstuffs given by the German Federal Ministry of Nutrition, Agriculture and Forestry (2000). From the standpoint of human nutrition, 43% of the conventionally grown wheat and 37% of the organically grown wheat contain toxin concentrations which exceed the tolerable daily intake (TDI) of DON established by the European Scientific Committee on Food, assuming a mean body weight of 60 kg at a mean wheat consumption.

Dombrink-Kurtzman, M. A. and L. W. Rooney (2002). Effect of nixtamalization on fumonisin-contaminated corn for production of tortillas. Bioactive Compounds in Foods. Washington, AMER CHEMICAL SOC. 816: 206-217. ://000180109800015 Fumonisins, mycotoxins produced by Fusarium verticilliodes (Sacc.) Niremberg (synonym F. monififorme Sheldon) and Fusarium proliferatum, are found in corn worldwide. Low levels of fumonisins can occur in corn products destined for human consumption. Studies were undertaken to determine the fate of fumonisins during nixtamalization (alkaline cooking), using normal-appearing corn that was naturally contaminated with fumonisin B-1 at 8.8 ppm. Samples from each stage of processing were analyzed to determine how much fumonisin remained in finished products. The majority of the fumonisin (76%) was present, primarily as hydrolyzed fumonisin B-1 in the steep water and wash water. Tortillas contained approximately 0.50 ppm fumonisin 13, plus 0.36 ppm hydrolyzed fumonisin B-1, representing 18.5% of the fumonisin B, detected in the raw corn. Nixtamalization appears to be a means for significantly reducing the amount of fumonisin in corn.

Doohan, F. M., J. Brennan, et al. (2004). "Influence of Climatic Factors on Fusarium Species Pathogenic to Cereals." European Journal of Plant Pathology 109(7): 755-768. http://dx.doi.org/10.1023/A:1026090626994 AND http://www.botanischergarten.ch/Bt/Doohan-Influence-Climatic-2004.pdf Fusarium head blight of small-grain cereals, ear rot of maize, seedling blight and foot rot of cereals are important diseases throughout the world. Fusarium graminearum, F. culmorum, F. poae, F. avenaceum and Microdochium nivale (formerly known as F. nivale) predominantly cause Fusarium diseases of small-grain cereals. Maize is predominantly attacked by F. graminearum, F. moniliforme, F. proliferatum and F. subglutinans. These species differ in their climatic distribution and in the optimum climatic conditions required for their persistence. This review deals with the influence of climate on the production and dispersal of inocula, growth, competition, mycotoxin production and pathogenicity. Most species produce inocula, grow best, and are most pathogenic to cereal heads at warm temperatures and under humid conditions. However, the optimal conditions for F. moniliforme and F. proliferatum maize ear rot tend to be hot and dry and M. nivale head blight, seedling blight and foot rot of small-grain cereals tend to occur under cooler conditions. Seedling blight and foot rot caused by other species are favoured by warm dry weather. Between them, these fungi produce four important classes of mycotoxins: trichothecenes, zearalenone, fumonisins and moniliformin. Conditions favourable for in vitro growth are also generally the most favourable for mycotoxin production on cereal grains. These fungi rarely exist in isolation, but occur as a complex with each other and with other Fusaria and other fungal genera. Climatic conditions will influence competition between, and the predominance of, different fungi within this complex.

Doohan, F. M., J. Brennan, et al. (2003). "Influence of climatic factors on Fusarium species pathogenic to cereals." European Journal of Plant Pathology 109(7): 755-768. ://000185661500011 Fusarium head blight of small-grain cereals, ear rot of maize, seedling blight and foot rot of cereals are important diseases throughout the world. Fusarium graminearum, F. culmorum, F. poae, F. avenaceum and Microdochium nivale (formerly known as F. nivale) predominantly cause Fusarium diseases of small-grain cereals. Maize is predominantly attacked by F. graminearum, F. moniliforme, F. proliferatum and F. subglutinans. These species differ in their climatic distribution and in the optimum climatic conditions required for their persistence. This review deals with the influence of climate on the production and dispersal of inocula, growth, competition, mycotoxin production and pathogenicity. Most species produce inocula, grow best, and are most pathogenic to cereal heads at warm temperatures and under humid conditions. However, the optimal conditions for F. moniliforme and F. proliferatum maize ear rot tend to be hot and dry and M. nivale head blight, seedling blight and foot rot of small-grain cereals tend to occur under cooler conditions. Seedling blight and foot rot caused by other species are favoured by warm dry weather. Between them, these fungi produce four important classes of mycotoxins: trichothecenes, zearalenone, fumonisins and moniliformin. Conditions favourable for in vitro growth are also generally the most favourable for mycotoxin production on cereal grains. These fungi rarely exist in isolation, but occur as a complex with each other and with other Fusaria and other fungal genera. Climatic conditions will influence competition between, and the predominance of, different fungi within this complex.

Dorner, J. W., R. J. Cole, et al. (1999). "Aflatoxin reduction in corn through field application of competitive fungi." J. Food Prot. 62: 650-656.

Dowd, P. F. (2000). "Indirect reduction of ear molds and associated mycotoxins in Bacillus thuringiensis corn under controlled and open field conditions: Utility and limitations." Journal of Economic Entomology 93(6): 1669-1679. ://000166049400016 AND NEBIS 20080315 In 1995, ears of a experimental inbred (CG59-2) containing a synthetic Bacillus thuringiensis Cry IA(b) gene driven by PEPC, pith and pollen promoters and artificially infested with Ostrinia nubilalis (Hubner) larvae in small plot studies were free from insect damage, whereas 40-50% of the corresponding non-Bt inbred ears were damaged. Bt inbred ears that were inoculated with Aspergillus flavus Link and Fusarium proliferatum T. Matsushima (Nirenberg) or exposed to natural mold inoculum after infestation with O. nubilalis were free of visible signs of mold, as compared with approximate to 30-40% of the non-Bt ears similarly treated. Results in 1996 using the same inbred with a single allele dose of the Bt gene showed similar trends. Mean total fumonisin levels for non-Bt versus Bt inbred ears were not significantly different (2.8 versus 0.8 ppm, respectively) in 1996. In paired hybrid studies run in 0.4-ha (1- acre) fields, an event 176 Bt hybrid had significantly lower amounts of damage and signs of Fusarium spp. mold, but not fumonisin, compared with a corresponding non-Bt hybrid from 1996 to 1998. However, two hybrid pairs that contained either MON810 or Bt11 constructs examined in similar fields at the same site had lower levels of fumonisin in both 1997 (30- to 40-fold) and 1998. High intrafield Variability in insect infestation and presence of Helicoverpa zea (Boddie) in Bt hybrids was apparently responsible for fewer significant differences in fumonisin levels in 1998. Similar trends for all three hybrid pairs were noted in small plot trials at another site. Incidence of other ear pests or insect predators varied as much among non-Bt hybrids as they did for Bt/non-Bt hybrid pairs.

Dowd, P. F. (2001). "Biotic and abiotic factors limiting efficacy of Bt corn in indirectly reducing mycotoxin levels in commercial fields." Journal of Economic Entomology 94(5): 1067-1074. ://000171545000009 AND http://www.botanischergarten.ch/Bt/Dowd-Factors-Mycotoxins-2001.pdf Incidence of insect damage, and association of insect damage with mycotoxigenic, corn ear molds and mycotoxins was examined in commercial fields of Bt and non-Bt hybrids of different backgrounds in Illinois in 1998 and 1999. Nearly 50% Helicoverpa zea (Boddie) infestation sometimes occurred in Bt hybrids that express high levels of the protein in silks and kernels. Damage by European corn borer, Ostrinia nubilalis Hubner, was uncommon, even in non-Bt ears. Levels of total fumonisins were generally less (15- to 1.8-fold) in Bt versus non-Bt hybrids at the same site, with some significant differences. There were several instances where there were no significant differences in fumonisin levels between low/no Bt kernel hybrids and Bt hybrids that produced high levels of the protein in the kernel and silk tissue. However, significant correlations were often noted between numbers of insect-damaged kernels and total fumonisin levels, especially in 1998, suggesting in these cases that reducing insect damage was still reducing fumonisin levels. There was variability between the correlation coefficient for numbers of insect damaged kernels and fumonisin levels at different sites for the same year, different hybrids at the same site, and the same hybrid for different years. Although reductions in fumonisins in Bt hybrids were more limited than reported in the past, planting the Bt hybrids still appears to be a useful method for indirectly reducing mycotoxins in corn ears.

Dowd, P. F. (2003). "Insect management to facilitate preharvest mycotoxin management." Journal of Toxicology-Toxin Reviews 22(2-3): 327- 350. ://000185165300010 Many species of insects can facilitate the entry of mycotoxin-producing fungi to commodities such as cotton seed, maize, peanuts, and tree nuts. The mycotoxins most commonly associated with insect damage are aflatoxin and fumonisin. Insecticides will likely remain an important management tool, especially as predictive models for forecasting mycotoxigenic fungi or mycotoxins become available. Plants with high levels of resistance to insects that facilitate mycotoxins are likely to assist in mycotoxin management. Several studies now indicate Bt maize hybrids that express the protein throughout the plant can prevent fumonisin levels rising above guideline levels of 1-2 ppm when European corn borers (Ostrinia nubilalis) are the predominant insect pests.

Dowd, P. F., F. E. Vega, et al. (1998). "Dusky sap beetle mediated dispersal of Bacillus subtilis to inhibit Aspergillus flavus and aflatoxin production in maize Zea mays L." Biocontrol Science and Technology 8(2): 221-235. ://000074804900005

Dowd, P. F. and D. G. White (2002). "Corn earworm, Helicoverpa zea (Lepidoptera : Noctuidae) and other insect associated resistance in the maize inbred Tex6." Journal of Economic Entomology 95(3): 628-634. ://000178371500016 A 2-yr field and laboratory study investigated insect resistance of the maize, Zea mays L., inbred Tex6, which has previously demonstrated resistance to Aspergillus ear rot and aflatoxin production, relative to susceptible inbred B73. Field studies indicated significantly greater resistance to insect feeding of V4 -V8 growth stage Tex6 plants compared with B73 plants in both years, primarily to flea beetles (Chaetonema spp.). Field studies of natural (1999) and artificial (2000) infestations of corn earworms, Helicoverpa zea (Boddie), indicated much lower levels of kernel damage at milk stage (approximately three-fold) and smaller surviving larvae (approximately three-fold) in Tex6 compared with B73 ears. At harvest similar trends in reduction of numbers of damaged kernels per ear, as well as incidence and numbers of kernels per ear symptomatically infected by Fusarium spp. were noted. Laboratory studies indicated little difference in mortality or survivor weight of caterpillars or sap beetle adults caged with milk stage kernels of the two inbreds. However, assays with silks indicated significantly greater mortality of H. zea in both 1999 and 2000, and European corn borer, Ostrinia nubilalis (Hubner) in 1999 (only year tested) when fed Tex6 silks compared with B73 silks. Pollinated Tex6 silks were generally darker colored and more toxic than unpollinated silks. Thus, it is possible that commercially usable inbreds with resistance to insects, which also contribute to the mycotoxin problem through vectoring and damage, could be produced using Tex6 as a source.

Dowell, F. E., T. C. Pearson, et al. (2002). "Reflectance and transmittance spectroscopy applied to detecting fumonisin in single corn kernels infected with Fusarium verticillioides." Cereal Chemistry 79(2): 222-226. ://000174407700009 Reflectance and transmittance visible and near-infrared spectroscopy were used to detect fumonisin in single corn kernels infected with Fusarium verticillioides. Kernels with >100 ppm and <10 ppm could be classed accurately as fumonisin positive or negative, respectively. Classification results were generally better for oriented kernels than for kernels that were randomly placed in the spectrometer viewing area. Generally, models based on reflectance spectra have higher correct classification than models based on transmittance spectra. Statistical analyses indicated that including near- infrared wavelengths in calibrations improved classifications, and some calibrations were improved by including visible wavelengths. Thus, the color and chemical constituents of the infected kernel contribute to classification models. These results show that this technology can be used to rapidly and nondestructively screen single corn kernels for the presence of fumonisin. and may be adaptable to on-line detection and sorting.

Dragacci, S. and J. M. Fremy (1996). "Application of immunoaffinity column cleanup to aflatoxin M(1) determination and survey in cheese." Journal of Food Protection 59(9): 1011-1013. ://A1996VK55700019

Dugyala, R. R., R. P. Sharma, et al. (1998). "Tumor necrosis factor-alpha as a contributor in fumonisin B-1 toxicity." Journal of Pharmacology and Experimental Therapeutics 285(1): 317-324. ://WOS:000072972200041 AND http://www.botanischergarten.ch/Bt/Dugyala-Tumor-Fumonisin-1998.pdf Fumonisin B-1 is a toxic product of Fusarium moniliforme, which inhibits ceramide synthase, leading to accumulation of free sphingoid bases. Despite its known biochemical action, the mechanism of toxicity is not fully understood. Male BALB/c mice were injected subcutaneously with 0 to 6.75 mg/kg/day of fumonisin B-1 for 5 days. One day after the last treatment, spleens were collected, and peritoneal macrophages were obtained from separate groups after an intraperitoneal injection of thioglycolate broth. Peripheral leukocyte counts were increased and kidney weights were decreased by fumonisin B-1 treatment. Presence of apoptotic cells in the liver and kidney of treated mice was confirmed by enzymatic immunoassay. Macrophages cultured with lipopolysaccharide indicated an increased secretion of tumor necrosis factor-alpha (TNF-alpha) but not of interleukin-1 alpha. No effect was seen on interferon-gamma production when splenocytes were incubated with concanavalin A. Elevation of leukocyte and reticulocyte counts was abrogated by pretreatment with anti-TNF-alpha antibody before a single dose fumonisin B-1 (25 mg/kg), supporting the hypothesis that the fumonisin B-1 toxicity involves TNF-alpha. Cultures of J774A.1 cells, when treated with fumonisin B-1, produced TNF-alpha in vitro. Results indicate that fumonisin B-1 toxicity may involve secretion of TNF-alpha by TNF-alpha- producing cells without altering interleukin-1 alpha or interferon-gamma. The influence on TNF-alpha-production may be a contributing factor to fumonisin B-1-induced apoptosis and other observed toxic effects in animals.

Dutton, M. F. and A. Kinsey (1995). "Occurrence of Mycotoxins in Cereals and Animal Feedstuffs in Natal, South-Africa 1994." Mycopathologia 131(1): 31-36. ://A1995TH95900005 AND http://www.botanischergarten.ch/Bt/Dutton-Occurrence-Mycotoxins-Natal-1995.pdf During the year of 1994, 417 samples of agricultural commodities, comprising: maize, compound animal feeds, oil seeds, soya bean, fish meal and forage were examined for fungi and over 20 mycotoxins using a multi-screen augmented with individual assays. Trichothecenes had the highest incidence of over 19% in all samples received, followed by aflatoxin at 6% and then zearalenone at 3%. Selected samples (73) were analyzed for fumonisin B1 and of these, 69 (94%) were found to be positive. Because of this result and high incidence of Fusarium spp. (over 70%) in maize and maize containing feeds, which was higher than either Aspergillus spp. (19%) or Penicillium spp. (33%), attention is drawn to the actual and potential presence of fumonisin in the food chain.

Duvick, J. (2001). "Prospects for reducing fumonisin contamination of maize through genetic modification." Environmental Health Perspectives 109: 337-342. ://000168824500023 and http://www.botanischergarten.ch/Mycotoxins/Duvik-Prospects-Fumonisin.pdf Fumonisins (FB) are mycotoxins found in Fusarium verticillioides-infected maize grain worldwide. Attention has focused on FBs because of their widespread occurrence, acute toxicity to certain livestock. and their potential carcinogenicity. FBs are present at low levels in most field- grown maize but may spike to high levels depending on both the environment and genetics of the host plant. Among the strategies for reducing risk of FB contamination in maize supplied to the market, development and deployment of Fusarium ear mold-resistant maize germplasm is a high priority. Breeding for increased ear mold tolerance and reduced mycotoxin levels is being practiced today in both commercial and public programs, but the amount of resistance achievable may be limited due to complicated genetics and/or linkage to undesirable agronomic traits. Molecular markers can be employed to speed up the incorporation of chromosomal regions that have a quantitative effect on resistance (quantitative trait loci). Transgenic approaches to ear mold/mycotoxin resistance are now feasible as well. These potentially include genetically enhanced resistance to insect feeding, increased fungal resistance, and detoxification/prevention of mycotoxins in the grain. An example of the first of these approaches is already on the market, namely transgenic maize expressing Bacillus thuringiensis (Bt) toxin, targeted to the European corn borer. Some Bt maize hybrids have the potential to reduce FB levels in field-harvested grain, presumably through reduced feeding of Bt-susceptible insects in ear tissues. However, improved ear mold resistance per se is still an important goal, as the plant will still be vulnerable to noninsect routes of entry to Fusarium. A second approach, transgene-mediated control of the ability of Fusarium to infect and colonize the ear, could potentially be achieved through overexpression of specific antifungal proteins and metabolites, or enhancement of the plant's own defense systems in kernel tissues. This has not yet been accomplished in maize, although promising results have been obtained recently in other monocots versus other fungal and bacterial pathogens. Achieving reproducible and stable enhanced ear mold resistance under field conditions will be immensely challenging for biotechnologists. A third approach, transgene strategies aimed at preventing mycotoxin biosynthesis, or detoxifying mycotoxins in plants, could provide further protection for the grower in environments where FBs present a risk to the crop even when the maize is relatively resistant to Fusarium mold. In one example of such a strategy, enzymes that degrade FBs have been identified in a filamentous saprophytic fungus isolated from maize, and corresponding genes have been cloned and are currently being tested in transgenic maize.

Duvick, J., T. Rood, et al. (1998). Detoxification of mycotoxins in planta as a strategy for improving grain quality and disease resistance. Molecular Genetics of Host Specific Toxins in Plant Diseases. K. Kohmoto and O. C. Yoder. Dordrecht, Kluwer: 369–381.

Edwards, O. E., B. A. Blackwell, et al. (1999). "The absolute stereochemistry of the ester functions of fumouisin B-1." Tetrahedron Letters 40(24): 4515-4518. ://000080547100016 Synthesis of an optically active gamma-lactone related to tricarballylic acid (TCA) and correlation of this to the same lactone derived from the two sidechain TCA esters at C-14 and C-15 of fumonisin B-1 has established that these esters have the R configuration. Crown copyright (C) 1999 Published by Elsevier Science Ltd. All rights reserved.

Ehrlich, K., B. Montalbano, et al. (1997). "Site-directed mutagenesis of the aflatoxin pathway biosynthesis regulatory gene, aflR." Faseb Journal 11(9): 473. ://000073305600960

Ehrlich, K. C., P. K. Chang, et al. (1994). "Partial Characterization of an Aflatoxin Biosynthesis Regulatory Protein Expressed in Escherichia-Coli." Faseb Journal 8(7): A1333-A1333. ://A1994NH51600648

Ehrlich, K. C., B. G. Montalbano, et al. (1998). "Alteration of different domains in AFLR affects aflatoxin pathway metabolism in Aspergillus parasiticus transformants." Fungal Genetics and Biology 23(3): 279-287. ://000078894000008 AFLR, a zinc binuclear cluster DNA-binding protein, is required for activation of genes comprising the aflatoxin biosynthetic pathway in Aspergillus spp. Transformation of Aspergillus parasiticus with plasmids containing the intact aflR gene gave clones that produced fivefold more aflatoxin pathway metabolites than did the untransformed strain. When a 13-bp region in the aflR promoter (positions -102 to -115 with respect to the ATG) was deleted, including a portion of a palindromic site previously shown to bind recombinant AFLR, metabolite production was 40% that of transformants with intact aflR. This result provides further evidence that this site may be involved in the autoregulation of aflR, Overexpression of pathway genes could also result from increased quantities of AFLR titrating out a putative repressor protein. In AFLR, a 20- amino-acid acidic region near its carboxy-terminus resembles the region in yeast GAL4 required for GAL80 repressor binding. When 3 of the acidic amino acids in this region were deleted, levels of metabolites were even higher than those produced by transformants with intact aflR, as would be expected if repressor binding was suppressed in transformants containing this altered protein. Transformation with plasmids mutated at the AFLR zinc cluster (Cys to Trp at amino acid position 49) or at a putative nuclear localization signal region (RRARK deleted) gave clones with one-fifth the metabolite production of the untransformed fungus in spite of the transformants making the same or more aflR mRNA. Since these transformants retained a copy of intact aflR, the latter results can be explained best by assuming that AFLR activates genes involved in aflatoxin production as a dimeric protein and that heterodimers containing both mutant and intact AFLR strands are inactive. (C) 1998 Academic Press.

Elbanna, A. A. and P. M. Scott (1983). "Fate of Myco-Toxins During Processing of Foodstuffs I-Aflatoxin-B1 During Making of Egyptian Bread." Journal of Food Protection 46(4): 301-304. ://WOS:A1983QN08500007

Elbanna, A. A. and P. M. Scott (1984). "Fate of Mycotoxins During Processing of Foodstuffs .3. Ochratoxin-a During Cooking of Faba Beans (Vicia-Faba) and Polished Wheat." Journal of Food Protection 47(3): 189-192. ://WOS:A1984SJ17100004

Eppley, R. M., L. Stoloff, et al. (1968). "Collaborative Study of a Versatile Procedure for Assay of Aflatoxins in Peanut Products Including Preparatory Separation and Confirmation of Identity." Journal of the Association of Official Analytical Chemists 51(1): 67-&. ://WOS:A1968A548300019

Escobar, A. and S. Regueiro (2002). "Determination of aflatoxin B1 in food and feedstuffs in Cuba (1990 through 1996) using an immunoenzymatic reagent kit (Aflacen)." Journal of Food Protection 65(1): 219-221. ://000173281900035 The presence of aflatoxin 131 was analyzed in imported food and feedstuffs of national production in the period of 1990 through 1996, destined to animal and human consumption using an immunoenzymatic reagent kit Aflacen, Ckure, la Habana, Cuba) with a detection limit of 0.3 mug/kg. It was found that the 17.04% of a total of 4,594 analyzed samples presented aflatoxin 131, and the biggest percentages were in sorghum and peanut with an 83.3 and 40.4%, respectively. The corn, oat, wheat, and soy are fundamental raw ingredients in the elaboration of concentrates. Percentages of contamination with aflatoxin B1 of 23.3, 10.7, 25, and 4.6 were found in corn, oat, wheat, and soy, respectively, Other analyzed foods like rice, beans, and peas presented percentages of contamination with aflatoxin 131 inferior to 5% of the analyzed samples. It was found that more than 455 samples surpassed the value of 10 mug/kg. Corn and peanut products present a high demand in population showing levels of contamination superior to 50 mug/kg. The 11.3% of the samples contaminated with aflatoxin B 1 have values between 1 and 20 mug/kg, where peanut and concentrates show the highest percentages (21.9 and 18.7), respectively. These results show levels of aflatoxin B 1 in the population that constitute a great risk for human and animal health.

Etcheverry, M., A. Nesci, et al. (1999). "Occurrence of Aspergillus section Flavi and aflatoxin B-1 in corn genotypes and corn meal in Argentina." Mycopathologia 147(1): 37-41. ://000087070100006 A study has been carried out in Argentina on samples of corn genotypes from a breeding station as well as in commercially available corn meal. All samples were analyzed for fungal infection and aflatoxin B-1. Mycological analysis of corn genotypes showed the presence of three principal genera of filamentous fungi Fusarium (100%), Penicillium (67%) and Aspergillus (60%). In the genus Fusarium three species were identified, F. moniliforme (42%), F. nygamai (56%) and F. proliferatum (1.8%). Eight species of Penicillium were identified, the predominant species isolated were P. minioluteum, P. funiculosum and P. variabile. In the genus ranked third in isolation frequency, two species were identified, A. flavus and A. parasiticus, the percentage of infection was 78% and 21%, respectively. Only one corn genotype was contaminated with aflatoxin B-1 at a level of 5 ppb. The corn meal samples showed great differences in fungal contamination, the values ranging from 1 x 10(1) to 7 x 10(5) cfu g(-1). Fusarium (68%), Aspergillus (35%) and Penicillium (21%) were the most frequent genera isolated. Among the genus, Aspergillus, A. parasiticus (38%) was the most frequent species isolated. All the samples of corn meal were negative to aflatoxin B-1. These results indicate a low degree of human exposure to aflatoxins in Argentina through the ingestion of maize or corn meal.

Etcheverry, M., A. Torres, et al. (2002). "In vitro control of growth and fumonisin production by Fusarium verticillioides and F-proliferatum using antioxidants under different water availability and temperature regimes." Journal of Applied Microbiology 92(4): 624-632. ://000175115500005 Aims: To examine the effect of butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), trihydroxybutyrophenone and propylparaben (PP) (at concentrations of 1-20 mmol l(-1)) on growth of and fumonisin production by Argentinian strains of Fusarium verticillioides and F. proliferatum. Methods and Results: Studies on lag phases prior to growth, relative growth rates and fumonisin concentrations were carried out in vitro in relation to water activity (0.995-0.93 a(w)) and temperature (18 and 25degreesC) on a maize meal agar. Overall, PP was the antioxidant which was most effective at inhibiting strains of both species. The lag phase prior to growth and growth rates were significantly decreased by PP and BHA at 10 and 20 mmol l(-1), regardless of the temperature or a(w) level tested. Total fumonisin production was higher at 0.98 a(w) and decreased by about 45-50% at 0.995 and 0.95 a(w). Overall, BHT only inhibited fumonisin production at 0.95 a(w) at 10 and 20 mmol l(-1), while BHA was effective at most a(w) levels tested at 10 and 20 mmol l(-1). Propylparaben completely inhibited fumonisin production by both F. verticillioides and F. proliferatum at > 1 mmol l(-1), regardless of the temperature or a(w) level. Small interstrain differences in the levels of inhibition by the antioxidants were observed for three F. verticillioides and four F. proliferatum strains at 0.995, 0.98 and 0.95 a(w). Propylparaben and BHA completely inhibited the growth of both species at the concentrations evaluated, regardless of the a, level. Conclusions: Two antioxidants show promise for the control of growth of and fumonisin production by these species over a wide range of environmental conditions. Significance and Impact of the Study: Potential exists for using such food-grade preservatives for prevention of mycotoxigenic fungi and their toxins entering the food chain.

Fakhoury, A. M. and C. P. Woloshuk (1999). "Amy1, the alpha-amylase gene of Aspergillus flavus: Involvement in aflatoxin biosynthesis in maize kernels." Phytopathology 89(10): 908-914. ://000082806500009 Aspergillus flavus is the causal agent of an ear and kernel rot in maize. In this study, we characterized an alpha-amylase- deficient mutant and assessed its ability to infect and produce aflatoxin in wounded maize kernels. The alpha-amylase gene Amyl was isolated from A. flavus, and its DNA sequence was determined to be nearly identical to Amy3 of A. oryzae. When Amyl was disrupted in an aflatoxigenic strain of A. flavus, the mutant failed to produce extracellular alpha-amylase and grew 45% the rate of the wild-type strain on starch medium. The mutant produced aflatoxin in medium containing glucose but not in a medium containing starch. The alpha-amylase-deficient mutant produced aflatoxin in maize kernels with wounded embryos and occasionally produced anatoxin only in embryos of kernels with wounded endosperm. The mutant strain failed to produce aflatoxin when inoculated onto degermed kernels. In contrast, the wild-type strain produced aflatoxin in both the endosperm and embryo. These results suggest that alpha- amylase facilitates aflatoxin production and growth of A. flavus from a wound in the endosperm to the embryo. A 14-kDa trypsin inhibitor associated with resistance to A. flavus and aflatoxin in maize also inhibited the alpha-amylase from A. flavus, indicating that it is a bifunctional inhibitor. The inhibitor may have a role in resistance, limiting the growth of the fungus in the endosperm tissue by inhibiting the degradation of starch.

Fakhoury, A. M. and C. P. Woloshuk (2001). "Inhibition of growth of Aspergillus flavus and fungal alpha- amylases by a lectin-like protein from Lablab purpureus." Molecular Plant-Microbe Interactions 14(8): 955-961. ://000169947000004 Aspergillus flavus is a fungal pathogen of maize causing an important ear rot disease when plants are exposed to drought and heat stress. Associated with the disease is the production of aflatoxins, which are a series of structurally related mycotoxins known to be carcinogenic. Previous research has suggested that the a-amylase of A. flavus promotes aflatoxin production in the endosperm of infected maize kernels. We report here the isolation and characterization of a 36-kDa alpha -amylase inhibitor from Lablab purpureus (AILP), AILP inhibited the alpha -amylases from several fungi but had little effect on those from animal and plant sources. The protein inhibited conidial germination and hyphal growth of A. flavus. The amino acid sequence indicated that AILP is similar to lectin members of a lectin-arcelin-alpha -amylase inhibitor family described in common bean and shown to be a component of plant resistance to insect pests. AILP also agglutinated papain-treated red blood cells from human and rabbit. These data indicate that AILP represents a novel variant in the lectin-arcelin-alpha -amylase inhibitor family of proteins having lectin-like and alpha -amylase inhibitory activity.

Fandohan, P., P. Hell, et al. (2003). "Review - Infection of maize by Fusarium species and contamination with fumonisin in Africa." Arfrican Journal of Biotechnology 2(12): 570-579. http://www.bioline.org.br/abstract?jb03108 and http://www.academicjournals.org/AJB/ Fusarium is one of the major fungal genera associated with maize in Africa. This genus comprises several toxigenic species including F. verticillioides and F. proliferatum, which are the most prolific producers of fumonisins. The fumonisins are a group of economically important mycotoxins and very common contaminants of maize-based foods and feeds throughout the world. They have been found to be associated with several animal diseases such as leukoencephalomalacia in horses and pulmonary oedema in pigs. Effects of fumonisins on humans are not yet well understood. However, their occurrence in maize has been associated with high incidences of oesophageal and liver cancer. Infection of maize by Fusarium species and contamination with fumonisins are generally influenced by many factors including environmental conditions (climate, temperature, humidity), insect infestation and pre- and postharvest handling. Attempts to control F. verticillioides and to detoxify or reduce fumonisin levels in maize have been undertaken. However, more research studies are urgently needed in order to understand more about this toxin. Fumonisins are less documented because they are recently discovered mycotoxins compared to aflatoxins. To date in Africa, apart from South Africa, very little information is available on Fusarium infection and fumonisin contamination in maize. It is a matter of great concern that on this continent, millions of people are consuming contaminated maize and maize-based foods daily without being aware of the danger.

Faraj, M. K., J. E. Smith, et al. (1991). "Interaction of Water Activity and Temperature on Aflatoxin Production by Aspergillus-Flavus and Aspergillus-Parasiticus in Irradiated Maize Seeds." Food Additives and Contaminants 8(6): 731-736. ://A1991HM13000007

Fazekas, B. (1999). "Fusariotoxicoses in swine." Magyar Allatorvosok Lapja 121(6): 340-343. ://000081335800006 The experience of the author regarding fusariotoxicosis, a common and economically serius problem in Hungarian swine herds, is reviewed based on Literature data and mycotoxicological research made at the Veterinary Institute of Debrecen. Highly contaminated feed causes typical oestrogen syndrome in sows with persistent (infertile) heat, return to oestrus, sometimes abortions. The majority of the piglets born alive are runts or have decreased viability. In boars, degeneration of the germinative epithelium in the testes causes infertility. Prolonged feeding of feedstuffs contaminated with lower levels of F-2 toxin often causes problems of the reproductive system in pigs. Estrogenism can often be observed in fetuses and newborn piglets. The trichothecene mycotoxins are generally cytotoxic to most cells as they inhibit cellular protein synthesis. Trihothecene toxicoses are characterised by reduced feed intake and sometimes vomiting may occur. Trichothecene mycotoxins also have immunosuppressive effects. T-2 toxin has an adverse effect on the reproductive system of sows. The author gives details of his experiments proving that the so- called fattening lung oedema of pigs, which has been present in Hungary for several decades, is caused by fumonisin B-1 mycotoxin, a regular contaminant of maize. The aetiology of this disease was unknown before. Experimental animals showed faintness and slight feed refusal already from the beginning of the illness, followed by the development of severe respiratory symptoms, including progressive hyperventilation The animals died soon after the first observation of clinical symptoms. Pulmonary oedema and hydrothorax were the most characteristic post-mortem findings but hepatic degeneration was also often observed.

Fazekas, B. and E. Bajmocy (1996). "Occurrence of the equine leukoencephalomalacia (ELEM) caused by fumonisin-B-1 mycotoxin in Hungary." Magyar Allatorvosok Lapja 51(8): 484-487. ://A1996VG02500009

Fazekas, B., E. Bajmocy, et al. (1997). "Fumonisine mycotoxicoses in Hungary. Leukoencephalomalacia in horses, fattening pulmonary oedema in pigs." Magyar Allatorvosok Lapja 119(3): 137-139. ://A1997WY75000002

Fazekas, B., E. Bajmocy, et al. (1998). "Fumonisin B-1 contamination of maize and experimental acute fumonisin toxicosis in pigs." Journal of Veterinary Medicine Series B-Infectious Diseases and Veterinary Public Health 45(3): 171-181. ://000073112800006

Fazekas, B., M. Kis, et al. (1996). "Data on the contamination of maize with fumonisin B-1 and other fusariotoxins in Hungary." Acta Veterinaria Hungarica 44(1): 25-37. ://A1996UR53800004

Fazekas, B., A. Koncz-Tar, et al. (1999). "Reusability of immunoaffinity columns for determination of fumonisins in maize." Natural Toxins 7(6): 259-263. ://000166017400006 Eighteen maize samples were assayed for fumonisin Bt (FB1) and B-2 content by immunoaffinity column coupled with high performance liquid chromatography (HPLC). The FumoniTest columns were used once for the isolation of fumonisins (single-use column method). In the second pari of the assay the columns were regenerated. After elution with methanol, PBS solution was left on the column for one day at room temperature to regenerate the columns (regenerated column method). The efficiency of columns regenerated twice was tested by determining FB1 recovery and the reproducibility of the determinations. The recovery rate of FB1 proved to be 82 % by the single-use column method (RSD: 5.7 %) and 82.6 % (RSD: 5.6 %) by the regenerated column method; 500-8000 ng FB1 loaded onto the columns did not affect column performances. Nearly identical values were obtained when the FB1 content of fumonisin-containing maize samples was determined by both methods. The results indicate that the FumoniTest columns can be regenerated by the method applied at least twice without decrease in column performance. The fumonisin affinity, capacity and specificity of the regenerated columns were nor changed. Thus, columns regenerated in this way can be used for determining the fumonisin content of maize samples at least three times. Copyright (C) 1999 John Wiley & Sons, Ltd.

Fazekas, B. and A. Tar (2001). "Determination of zearalenone content in cereals and feedstuffs by immunoaffinity column coupled with liquid chromatography." Journal of Aoac International 84(5): 1453-1459. ://000171421000019 The zearalenone content of maize, wheat, barley, swine feed, and poultry feed samples was determined by immunoaffinity column cleanup followed by liquid chromatography (IAC-LC). Samples were extracted in methanol-water (8 + 2, v/v) solution. The filtered extract was diluted with distilled water and applied to immunoaffinity columns. Zearalenone was eluted with methanol, dried by evaporation, and dissolved in acetonitrile- water (3 + 7, v/v). Zearalenone was separated by isocratic elution of acetonitrile-water (50 + 50, v/v) on reversed-phase C-18 column. The quantitative analysis was performed by fluorescence detector and confirmation was based on the UV spectrum obtained by a diode array detector. The mean recovery rate of zearalenone was 82-97% (RSD, 1.4-4.1 %) on the original (single-use) immunoaffinity columns. The limit of detection of zearalenone by fluorescence was 10 ng/g at a signal-to-noise ratio of 10:1 and 30 ng/g by spectral confirmation in UV. A good correlation was found (R-2 = 0.89) between the results obtained by IAC-LC and by the official AOAC-LC method. The specificity of the method was increased by using fluorescence detection in parallel with UV detection. This method was applicable to the determination of zearalenone content in cereals and other kinds of feedstuffs. Reusability of immunoaffinity columns was examined by washing with water after sample elution and allowing columns to stand for 24 h at room temperature. The zearalenone recovery rate of the regenerated columns varied between 79 and 95% (RSD, 3.2-6.3%). Columns can be regenerated at least 3 times without altering their performance and without affecting the results of repeated determinations.

Fazekas, B. and H. E. Tothne (1995). "Incidence of Fumonisin-B-1 Mycotoxin in Maize Cultivated in Hungary." Magyar Allatorvosok Lapja 50(8): 515-518. ://A1995RV54400013

Fernandez-Surumay, G., G. Negron-Gonzalez, et al. (2000). "Report of quantitative analysis of aflatoxins by ELISA method in raw ingredients samples of balanced feed for poultry from a factory located at Mara municipality of Zulia State, Venezuela." Revista Cientifica-Facultad De Ciencias Veterinarias 10(1): 63-68. ://000085622500011 Aflatoxin is a secondary metabolite of several species of fungus, like Aspergillus flavus mainly. It can produce many adverse effects. These effects range from a decrease of egg production, growth depression in broilers, and an increase of mortality in adult birds. The presence of this toxin has been detected in several grains, organic tissues and animal fluids using cromatographic and inmunochemical methods. For this study was used the ELISA test with a spectrophotometer at 650 nm as the determination method. Forty samples, treated with methilic alcohol were analyzed. Five different raw ingredients used in the production of concentrate feed for poultry were sampled, elaborated in a factory located at Mara municipality of Zulia state. Seventeen of analyzed samples resulted positive for aflatoxin in variable amounts. The corn flour resulted with the highest values ((X) over bar = 34.1 ppb). The aflatoxin content of the rest of the samples was significantly lower (milled yellow corn: (X) over bar = 0.98 ppb, soy flour: (X) over bar = 2 ppb, milled sorghum: (X) over bar = 0.25 ppb and wheat bran: (X) over bar = 0.0 ppb).

Figueira, E. L. Z., A. Blanco-Labra, et al. (2003). "New amylase inhibitor present in corn seeds active in vitro against amylase from Fusarium verticillioides." Plant Disease 87(3): 233-240. ://000181188500004 A screening for specific amylase inhibitor levels against amylase from Fusarium verticillioides (Fusarium mondiforme), the most relevant mycotoxigenic fungus in corn, was conducted on 37 corn hybrids. The amylase inhibitor levels in these hybrids ranged from 5.5 to 16.0 amylase inhibitor units per gram of corn (AIU/g) in the MASTER and AG5011 hybrids, respectively. The hybrid with the maximum content of inhibitor was used as the source of this new protein. The inhibitor was partially purified using fractional precipitation, gel filtration on Sephadex G75 column, high performance liquid chromatography (HPLC) Superose HR 10130 column, and HPLC anion exchange chromatography, obtaining a 20.7-fold purification. Electrophoresis after denaturing and beating under reductive conditions showed an apparent 23.8 kDa molecular mass and an acidic isoelectric point of 5.4, which differs from previous molecular masses reported for other inhibitors present in corn seeds (14 and 22 kDa). This inhibitor showed activity against amylases from human saliva and pancreas, from the fungi E verticithoides and Aspergillus flavus, and from the insects Acanthoscelides obteclus, Zabrotes subfasciatus, Tribolitan castaneum, and Sitotroga cerealella. The mycoflora found in the corn grain indicated Fusarium sp. as the most prevalent fungi (81.1% of the samples), with a count ranging from 1.5 x 10(2) to 2.4 x 10(6) CFU/g of corn. The presence of fumonisms was detected in 21 out of the 37 hybrids studied, ranging from 0.05 to 2.67 mug of FB per gram of corn. No correlation could be established between this amylase inhibitor level in the corn seeds and the presence of Fusarium sp. or with the fumonisin content under the experimental conditions of the test.

Figueira, E. L. Z., E. Y. Hirooka, et al. (2003). "Characterization of a hydrophobic amylase inhibitor from corn (Zea mays) seeds with activity against amylase from Fusarium verticillioides." Phytopathology 93(8): 917-922. ://000184299400002 A hydrophobic 19.7-kDa amylase inhibitor (Al) was purified from corn kernels by 95% ethanol extraction and anionic exchange chromatography. The Al has an isoelectric point of 3.6 and was very stable at different pH values and high temperatures, maintaining 47.6% activity after heating to 94degreesC for 60 min. Amino acid analysis indicated high valine. leucine. glycine. alanine, and glutamic acid/glutamine content, and especially high valine content (41.2 mol%). This inhibitor is not a glycoprotein. It required 30- min preincubation to maximize complex enzyme-inhibitor formation when the amylase from Fusarium verticillioides was tested. The optimal pH of interaction was 6.5. It showed broad-spectrum activity including the following amylases: human saliva, porcine pancreas, E verticillioides, as well as those from some insects of agricultural importance (Acanthoscelides obtectus, Zabrotes subfasciatus. Sitophilus zeamais, and Prostephanus truncatus). This novel hydrophobic protein not only inhibited the amylase from E verticillioides but also decreased the conidia germination. Thus, this protein represents an approach to decrease the production of fumonisin in corn, either by using it as a molecular marker to detect fungal resistance or through genetic engineering.

Fincham, J. E., W. F. O. Marasas, et al. (1992). "Atherogenic Effects in a Nonhuman Primate of Fusarium- Moniliforme Cultures Added to a Carbohydrate-Diet." Atherosclerosis 94(1): 13-25. ://A1992HU70200002 Adding less than 0.5% w/w of culture material of strain MRC 826 of the fungus Fusarium moniliforme to a carbohydrate diet low in fat resulted in an atherogenic plasma lipid profile in a non-human primate. Simultaneously increased plasma fibrinogen and activity of blood coagulation factor VII could enhance atherogenesis. This unique potential for promotion of atherosclerosis was probably secondary to chronic hepatotoxicity as indicated by liver fibrosis and elevated cholesterol, albumin and the enzymes AST, ALT, LD, GGT and ALP in serum. The cholesterol and enzymes responded in proportion to the calculated doses of fumonisin mycotoxins in the F. moniliforme MRC 826 cultures. Fumonisins are water soluble and heat stable. Thrombotic, hepatotoxic, carcinogenic and cerebral effects of MRC 826 culture material and fumonisins are well known in non-primates. The estimated fumonisin concentrations tested fall within a range due to natural contamination of human foods. The results suggest that all maize grain products should be analysed for fumonisins.

Flaherty, J. E., A. M. Pirttila, et al. (2003). "PAC1, a pH-regulatory gene from Fusarium verticillioides." Applied and Environmental Microbiology 69(9): 5222-5227. ://000185437000023 Fumonisins are a group of mycotoxins that contaminate maize and cause leukoencephalomalacia in equine, pulmonary edema in swine, and promote cancer in mice. Fumonisin biosynthesis in Fusarium verticillioides is repressed by nitrogen and alkaline pH. We cloned a PACC-like gene (PAC1) from F. verticillioides. PACC genes encode the major transcriptional regulators of several pH- responsive pathways in other filamentous fungi. In Northern blot analyses, a PAC1 probe hybridized to a 2.2-kb transcript present in F. verticillioides grown at alkaline pH. A mutant of F. verticillioides with a disrupted PAC1 gene had severely impaired growth at alkaline pH. The mutant produced more fumonisin than the wild type when grown on maize kernels and in a synthetic medium buffered at an acidic pH, 4.5. The mutant, but not the wild type, also produced fumonisin B, when mycelia were resuspended in medium buffered at an alkaline pH, 8.4. Transcription of FUM1, a gene involved in fumonisin biosynthesis, was correlated with fumonisin production. We conclude that PAC1 is required for growth at alkaline pH and that Pac1 may have a role as a repressor of fumonisin biosynthesis under alkaline conditions.

Flaherty, J. E. and C. P. Woloshuk (2004). "Regulation of fumonisin biosynthesis in Fusarium verticillioides by a zinc binuclear cluster-type gene, ZFR1." Applied and Environmental Microbiology 70(5): 2653-2659. ://000221340400011 Fusarium verticillioides, a pathogen of maize, produces a class of mycotoxins called fumonisins in infected kernels, In this study, a candidate regulatory gene, ZFR1, was identified in an expressed sequence tag library enriched for transcripts expressed by F. verticillioides during fumonisin B-1 (FB1) biosynthesis. ZFR1 deletion mutants exhibited normal growth and development on maize kernels, but fumonisin production was reduced to less than 10% of that of the wild-type strain. ZFR1 encodes a putative protein of 705 amino acids with sequence similarity to the Zn(II)2Cys6 binuclear cluster family that. are regulators of both primary and secondary metabolism in fungi. Expression of ZFR1 in colonized germ and degermed kernel tissues correlated with FB1 levels. Overexpression of ZFR1 in zfr1 mutants restored FB1 production to wild-type levels; however, FB1 was not restored in an fcc1 (Fusarium C-type cyclin) mutant by overexpression of ZFR1. The results of this study indicate that ZFR1 is a positive regulator of FB1 biosynthesis in F. verticillioides and suggest that FCC1 is required for ZFR1 function.

Food Standard Agency (2003). "Contaminated maize meal withdrawn from sale." from http://www.food.gov.uk/news/newsarchive/2003/sep/maize and http://www.food.gov.uk/news/newsarchive/2003/sep/moremaize and http://www.food.gov.uk/multimedia/pdfs/maizemeal10.pdf. Two batches of maize meal have been voluntarily withdrawn from sale after tests showed that they contained unusually high levels of fumonisins, a group of undesirable chemicals known as mycotoxins.

The two products, Fresh and Wild Organic Maize Meal and Infinity Foods Organic Maize Meal, were tested as part of an on-going survey being carried out by the Food Standards Agency to check for levels of a range of mycotoxins in maize and maize products. Results received so far in the survey for other maize-containing products, such as corn flour and polenta, are not a cause for concern.

Fumonisins have been shown to cause liver and kidney damage in animals after long-term exposure and it is possible that they could have the same effect on humans.

While there is no limit for fumonisins in food currently, the European Commission (EC) has proposed a limit of 500 micrograms per kilogram (mcg/kg).

The levels found in the two maize meal samples are above the proposed EC limit and are considered to be high at 4712 and 20435 mcg/kg. However, there is unlikely to be any immediate risk to health.

The two products have been withdrawn from sale as a precaution and the EC has been notified about the results. The Food Standards Agency is now carrying out further testing to see if any other brands are affected.

Mycotoxins, like fumonisins, are produced by a range of moulds growing on food crops in the field and in storage.

Previous surveys have shown that levels of mycotoxins in food are generally very low.

The Food Standards Agency carries out a rolling programme of research and surveys to monitor products that might be affected and takes action when unacceptable levels are found.

Gamanya, R. and L. Sibanda (2001). "Survey of Fusarium moniliforme (F-verticillioides) and production of fumonisin B-1 in cereal grains and oilseeds in Zimbabwe." International Journal of Food Microbiology 71(2-3): 145-149. ://000173069200005 In a national survey carried out in 1995 and 1996, the distribution of Fusarium moniliforme ( = F. verticillioides) and fumonisin B 1 (1713) levels in cereals and oilseeds from Zimbabwe were analyzed. The results of this study showed that the incidence of F. moniliforme and other Fusarium species and levels of FB1 generally decreased from regions with high rainfall and annual moderate temperatures to low rainfall regions. There was no Fusarium contamination and FB1 was not detected in sunflowers and soybeans. The incidence of F. moniliforme and its metabolite exhibited a substrate preference with high incidences of Fusarium species and high FB1 levels being recorded for maize followed by wheat, rapoko and sorghum. (C) 2001 Published by Elsevier Science B.V.

Ganassi, S., A. Moretti, et al. (2001). "Effect of Fusarium, Paecilomyces and Trichoderma formulations against aphid Schizaphis graminum." Mycopathologia 151(3): 131-138. ://000170946000003 Fungal strains belonging to the genera Fusarium Paecilomyces and Trichoderma were tested in vitro in order to study their effects against Schizaphis graminum one of the major pests of cereal crops around the world. Biological assays were performed using a solid formulation that was obtained from fungal cultures grown on rice and then finely ground (less than or equal to0.2 mm). The occurrence of toxic secondary metabolites (fumonisin B-1 and beauvericin) produced by these fungi was also investigated. In each experiment, three groups of aphids: 15-hour old larvae, 5-day old nymphs with wing buds and wingless morphs were treated with a suspension of a fungal formulation. Some strains belonging to the genera Fusarium and Trichoderma significantly controlled the specimens of the three groups of S. graminum. The F. proliferatum strain ITEM 1407, producing a high level of fumonisin B-1 in the culture (1250 mug/g), and F. larvarum strain ITEM 2139 had high insecticidal activity (> 60%) within 10 minutes after application. As F. larvarum ITEM 2139 did not produce metabolites toxic to mammals, it might be a good candidate as a biocontrol agent of S. graminum in the field.

Gardner, H. D., W. P. Williams, et al. (2006). "Effects of xenia on Aspergillus flavus infection and aflatoxin accumulation in maize inbreds." Crop Science 46(5): 2151-2154. ://WOS:000240821800038 Aspergillus flavus Link:Fries infection and aflatoxin contamination pose an economic threat to maize (Zea mays L.) producers of the United States. Efforts to identify germplasm resistant to A. flavus infection and aflatoxin accumulation have raised questions regarding the role of xenia, the pollen effect on the embryo and endosperm, in resistance of maize grain to the pathogen. The objective of this study was to evaluate the importance of xenia on A. flavus infection and aflatoxin accumulation in seed of eight inbred lines with different levels of resistance to A. flavus infection and aflatoxin contamination. Resistant and susceptible maize lines were hand-pollinated following a diallel mating design to produce seed for trials. The ears were inoculated 14 d after pollination with A. flavus spores. Grain was plated on agar to determine the extent of A. flavus infection and analyzed to measure aflatoxin content. Significant differences were detected among seed parents for both aflatoxin accumulation and A. flavus infection in both 2003 and 2004. The effects of pollen source were not significant on aflatoxin contamination or A. flavus infection in either 2003 or 2004. These results are consistent with xenia having little or no effect on A. flavus infection or aflatoxin accumulation. The results further suggest that reliable evaluation of A. flavus infection and aflatoxin contamination can be gained from open-pollinated field experiments.

Gardner, H. D., W. P. Williams, et al. (2007). "Diallel analysis of aflatoxin accumulation in maize." Field Crops Research 102(1): 60-63. ://WOS:000246533800007 Since its discovery in numerous feedstuffs, aflatoxin, a carcinogenic compound produced by the fungus Aspergillus flavus Link ex Fries, has caused much concern among consumers and producers alike. This toxin poses a serious economic threat to maize (Zea mays L.) producers of the southeastern and midwestern regions of the United States. Efforts to identify maize germplasm that is resistant to aflatoxin accumulation and to investigate the genetic basis of this resistance have been undertaken at numerous research institutions. The objectives of this study were to (1) evaluate aflatoxin accumulation in grain harvested from rnaize inbred lines and a diallel cross among these lines, (2) determine the importance of general and specific combining abilities in inheritance of resistance to aflatoxin accumulation, and (3) estimate general and specific combining ability effects associated with resistance to aflatoxin accumulation in the inbred lines and crosses among them. Eight inbred lines and a diallel cross of the maize lines were inoculated with an A. flavus spore suspension 12-14 d after silk emergence. Following harvest, aflatoxin content was determined from samples of grain. Statistical analyses performed using SAS general linear models (GLM) and DIALLEL-SAS indicated that general and specific combining ability were significant sources of variation in the inheritance of resistance to aflatoxin accumulation. The inbred line Mp313E, which was developed and released as a source of resistance to aflatoxin contamination, had significantly lower aflatoxin accumulation than other lines. Mo18W exhibited excellent general combining ability for reduced aflatoxin accumulation when crossed with the other lines. Both Mp313E and Mo18W could be useful in breeding programs to develop aflatoxin-resistant maize hybrids. Mp339, SC212M, and Ab24E demonstrated aflatoxin susceptibility as both inbreds and in single crosses. (C) 2007 Elsevier B.V. All rights reserved.

Gelderblom, W. C. A. (1995). "Fumonisin Toxicity and Metabolism Studies in South-Africa." Abstracts of Papers of the American Chemical Society 209: 119-AGFD. ://A1995QP23200119

Gelderblom, W. C. A., S. Abel, et al. (2001). "Fumonisin-induced hepatocarcinogenesis: Mechanisms related to cancer initiation and promotion." Environmental Health Perspectives 109(2 supplement): 291-300. ://WOS:000168824500016 AND http://www.botanischergarten.ch/Bt/Gelderblom-Fumonisin-induced-2001.pdf We review the hepatocarcinogenic effects of fungal cultures of Fusarium verticillioides(= Fusarium moniliforme) strain MRC 826 in male ED IX rats. Subsequent chemical analyses of the fumonisin B (FB) mycotoxin content in the culture material used and long-term carcinogenesis studies with purified FB1 provide information about dose-response effects, relevance of hepatotoxicity during FB1- induced carcinogenesis, and the existence of a no-effect threshold. Fumonisin intake levels of between 0.08 and 0.16 mg FB/100 g body weight (bw)/day over approximately 2 years produce liver cancer in male ED IX rats. Exposure levels < 0.08 mg FB/100 g bw/day fail to induce cancer, although mild toxic and preneoplastic lesions are induced. The nutritional status of the diets used in the long-term experiments was marginally deficient in lipotropes and vitamins and could have played an important modulating role in fumonisin-induced hepatocarcinogenesis. Short-term studies in a cancer initiation/promotion model in rat liver provided important information about the possible mechanisms involved during the initial stages of cancer development by this apparently nongenotoxic mycotoxin. These studies supported the findings of long-term investigations indicating that a cytotoxic/proliferative response is required for cancer induction and that a no-effect threshold exists for cancer induction. The mechanisms proposed far cancer induction are highlighted and include the possible role of oxidative damage during initiation and the disruption of lipid metabolism, integrity of cellular membranes, and altered growth-regulatory responses as important events during promotion.

Gelderblom, W. C. A., S. Abel, et al. (1999). "Regulation of fatty acid biosynthesis as a possible mechanism for the mitoinhibitory effect of fumonisin B-1 in primary rat hepatocytes." Prostaglandins Leukotrienes and Essential Fatty Acids 61(4): 225-234. ://000083665100003 The mitoinhibitory effect of fumonisin B-1 (FB1) on the mitogenic response of epidermal growth factor (EGF) was investigated in primary hepatocyte cultures with respect to the alterations in the omega 6 fatty acid metabolic pathway. Fatty acid analyses of hepatocytes showed that EGF treatment resulted in a significant decrease in the relative levels of 20:4 omega 6 (arachidonic acid) and an increase in 18:2 omega 6 (linoleic acid). Supplementation of the hepatocyte cultures with 20:4 omega 6 in the absence of EGF resulted in an increase in the total omega 6 and omega 6/omega 3 fatty acid ratio. Addition of 20.5 omega 3 (eicosapentaenoic acid) resulted in an increase of the relative levels of the long chain omega 3 fatty acids at the expense of the omega 6 fatty acids. When 26:4 omega 6 and 20:5 omega 3 was added in the presence of EGF, the mitogenic response of EGF was increased and decreased respectively. When compared to the fatty acid profiles in the absence of EGF, the decreased mitogenic response coincided with a decrease of total omega 6 fatty acids and total polyunsaturated fatty acids (PUFA). In addition, the saturated and mono-unsaturated fatty acids increased and the polyunsaturated/saturated (P/S) fatty acid ratio decreased which implied a more rigid membrane structure. Addition of prostaglandin E-2, (PGE(2)) and prostaglandin E-1 (PGE(1)) stimulated and inhibited the mitogenic response respectively. Ibuprofen, a known cyclooxygenase inhibitor, and FB1 inhibited the EGF-induced mitogenic response in a dose- dependent manner. The mitoinhibitory effect of FB1 on the EGF response was counteracted by the addition of PGE(2). FB1 also disrupts the omega 6 fatty acid metabolic pathway in primary hepatocytes, resulting in the accumulation of C18:2 omega 6 in phospatidylcholine and triacylglicerol. The disruption of the omega 6 fatty acid metabolic pathway and/or prostaglandin synthesis is likely to be an important event in the mitoinhibitory effect of FB1 on growth factor responses. (C) 1999 Harcourt Publisher Ltd.

Gelderblom, W. C. A., M. E. Cawood, et al. (1994). "Fumonisin B-1 Dosimetry in Relation to Cancer Initiation in Rat-Liver." Carcinogenesis 15(4): 790-790. ://A1994NE66500039

Gelderblom, W. C. A., M. E. Cawood, et al. (1993). "Structure-Activity-Relationships of Fumonisins in Short-Term Carcinogenesis and Cytotoxicity Assays." Food and Chemical Toxicology 31(6): 407-414. ://A1993LK34100002 A short-term rat liver cancer initiation/promotion model was used to monitor the cancer-initiating activity of the mycotoxins fumonisin B1 (FB1), fumonisin B2 (FB2) and fumonisin B3 (FB3) as well as the N-acetyl derivatives of FB1 and FB2, and their respective hydrolysis products the aminopolyols. The induction of resistant hepatocytes, which develop into hepatocyte nodules on selection by the 2-acetylaminofluorene- partial hepatectomy promoting treatment, was taken as the endpoint for cancer initiation. When fed at a level of 1000 mg/kg diet for 21 days, only the fumonisins B were found to initiate cancer. In addition, these mycotoxins caused a marked reduction in the rat body weight during the initiating treatment. Comparative cytotoxicity studies in primary rat hepatocytes indicated that FB2 exhibited the highest cytotoxic effect followed by FB3 and FB1. In general, the fumonisin B mycotoxins exhibited a low cytotoxic effect in hepatocyte cultures, and the concentrations of FB1 and FB2 that caused a 50% (CD50) release of the total lactate dehydrogenase (LDH) were in the order of 2000 and 1000 muM, respectively. The N- acetyl derivatives also exhibited a cytotoxic effect, but were not as cytotoxic as the parent molecules at high concentrations. The respective aminopolyols exhibited a higher cytotoxicity than did the parent compounds, while tricarballylic acid (TCA) exhibited no dose response effect despite the fact that it had a higher background cytotoxicity compared with the control. The apparent inability of the aminopolyols to act as cancer initiators could be related to a lack in absorption from the gut. An active role of the TCA moiety in the absorption of the fumonisins from the gut was proposed. The present study indicated that the intact molecule and the presence of a free amino group determine the cancer- initiating activity of the fumonisins, and need to be considered in the detoxification procedures of these compounds in foods and feeds.

Gelderblom, W. C. A., D. Galendo, et al. (2001). "Cancer initiation by fumonisin B-1 in rat liver - role of cell proliferation." Cancer Letters 169(2): 127-137. ://WOS:000169996600004 AND http://www.botanischergarten.ch/Bt/Gelderblom-Cancer-Initiation-2001.pdf

Gelderblom, W. C. A., K. Jaskiewicz, et al. (1988). "Fumonisins - Novel Mycotoxins with Cancer-Promoting Activity Produced by Fusarium- Moniliforme." Applied and Environmental Microbiology 54(7): 1806-1811. ://A1988P186700029

Gelderblom, W. C. A., N. P. J. Kriek, et al. (1991). "Toxicity and Carcinogenicity of the Fusarium-Moniliforme Metabolite, Fumonisin-B1, in Rats." Carcinogenesis 12(7): 1247-1251. ://A1991FW43400017 A semi-purified corn-based diet containing 50 mg/kg of pure (not < 90%) fumonisin B1 (FB1), isolated from culture material of Fusarium moniliforme strain MRC 826, was fed to a group of 25 rats over a period of 26 months. A control group of 25 rats received the same diet without FB1. Five rats from each group were killed at 6, 12, 20 and 26 months. The liver was the main target organ in the FB1-treated rats and the hepatic pathological changes were identical to those previously reported in rats fed culture material of F. moniliforme MRC 826. All FB1-treated rats that died or were killed from 18 months onwards suffered from a micro- and macronodular cirhosis and had large expansile nodules of cholangiofibrosis at the hilus of the liver. Ten out of 15 FB1-treated rats (66%) that were killed and/or died between 18 and 26 months developed primary hepatocellular carcinoma. Metastases to the heart, lungs or kidneys were present in four of the rats with hepatocellular carcinoma. No neoplastic changes were observed in any of the control rats. Chronic interstitial nephritis was present in the kidneys of FB1-treated rats killed after 26 months. No lesions were observed in the esophagus, heart or forestomach of FB1-treated rats and this is contrary to previous findings when culture material of the fungus was fed to rats. It is concluded that FB1 is responsible for the hepatocarcinogenic and the hepatotoxic but not all the other toxic effects of culture material of F. moniliforme MRC 826 in rats.

Gelderblom, W. C. A., S. Lebepe-Mazur, et al. (2001). "Toxicological effects in rats chronically fed low dietary levels of fumonisin B-1." Toxicology 161(1-2): 39-51. ://000168347100004 The toxicity of low dietary levels of fumonisin B-1 (FB1), i.e. 1, 10 and 25 mg FB,;kg diet, were monitored in rats over a period of 24 months. No effects on the body weight gain and feed intake profiles were noticed, while the relative liver weight was significantly (P < 0.05) reduced in the FB1-treated rats. Mild toxic effects, including single cell necrosis (apoptosis). proliferation of bile duct epithelial cells (DEC), and early signs of fibrosis, bile duct hyperplasia and in one case, adenofibrosis, were noticed in the liver of the rats fed the highest (25 mg/FB1/kg diet) dietary level. A significant (P < 0.05) increase in the level of oxidative damage was also noticed in the liver of the rats of high dosage dietary group. The toxic effects were less severe in the 10 mg FB1/kg dietary group, whilst only a few ground glass foci were observed in the 1 mg FB1/kg dietary group. Hepatocyte nodules, staining positively for glutathione-S-transferase (placental form, PGST), were observed macroscopically in the 25 mg FB1/kg treated group and to a lesser extent in the 10 mg FB1/kg treated rats. The most prominent toxic lesions by FB1 (10 and 25 mg FB1/kg dietary groups) in the kidneys were restricted to the tubular epithelium manifesting as granular cast, necrosis, apoptosis, calcification and the presence of regenerative foci in the proximal convoluted tubules. The existence of a cytotoxic/proliferative threshold with respect to cancer induction by FB, in rat liver became apparent, with a dietary level of < 10-mg FB1/ikg diet as a no effect threshold for the induction of hepatocyte nodules. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.

Gelderblom, W. C. A., W. F. O. Marasas, et al. (2002). "Interaction of fumonisin B-1 and aflatoxin B-1 in a short-term carcinogenesis model in rat liver." Toxicology 171(2-3): 161-173. ://000174005100010 The co-existence of the fumonisin and aflatoxin mycotoxins in corn merited studies to investigate their possible synergistic toxicological and carcinogenic effects. When utilising a short- term carcinogenesis model in rat liver, both the compounds exhibited slow cancer initiating potency as monitored by the induction of foci and nodules stained positively for the placental form of gluthatione-S-transferase (GSTP(+)). However, when rats were treated in a sequential manner with AFB(1) and FB1 the number and size of GSTP(+) lesions significantly increased as compared to the separate treatments. Histopathological analyses indicated that the individual treatments showed far less toxic effects, including occasional hepatocytes with dysplastic nuclei, oval cell proliferation and, in the case of FBI, a few apoptotic bodies in the central vein regions. The sequential treatment regimen induced numerous foci and dysplastic hepatocyte nodules, and with oval cells extending from the periportal regions into the centrilobular regions. This would imply that, in addition to the cancer promoting activity of FBI of AFB(1)-initiated hepatocytes, the AFB(1) pre-treatment enhanced the FBI initiating potency, presumably by rendering the liver more susceptible to the toxic effects of FBI. The co- occurrence of AFB(1) and FB1 in corn consumed as a staple diet could pose an increased risk and should be included in establishing risk assessment parameters in humans. (C) 2002 Elsevier Science Ireland Ltd. All rights reserved.

Gelderblom, W. C. A., W. F. O. Marasas, et al. (1992). "Fumonisins - Isolation, Chemical Characterization and Biological Effects." Mycopathologia 117(1-2): 11-16. ://A1992HL60100003 The fumonisin B mycotoxins (FB1 and FB2) have been purified and characterized from corn cultures of Fusarium moniliforme strain MRC 826. Fumonisin B1 (FB1), the major fumonisin produced in culture, has been shown to be responsible for the major toxicological effects of the fungus in rats. horses and pigs. Recent investigations on the purification of compounds with chromatographic characteristics similar to FB1 have led to the identification of two new fumonisins, FB3 and FB4. Fumonisins A1 and A2, the N-acetyl derivatives of FB1 and FB2 respectively, were also purified and shown to be secondary metabolites of the fungus. Short-term carcinogenesis studies in a rat liver bioassay indicated that over a period of 15 to 20 days, at dietary levels of 0.05-0.1%, FB2 and FB3 closely mimic the toxicological and cancer initiating activity of FB1 and thus could contribute to the toxicological effects of the fungus in animals. In contrast, no biological activity could be detected for FA1 under identical experimental conditions. These studies and others have indicated that the fumonisin B mycotoxins, although lacking mutagenicity in the Salmonella test or genotoxicity in the DNA repair assays in primary hepatocytes, appear to induce resistant hepatocytes similar to many known hepatocarcinogens.

Gelderblom, W. C. A., W. Moritz, et al. (2002). "Lipids and Delta 6-desaturase activity alterations in rat liver microsomal membranes induced by fumonisin B-1." Lipids 37(9): 869-877. ://000179265500005 Alterations in the membrane structure and function of hepatocyte membranes by fumonisin B-1 (FB1) have been proposed to play an important role in the disruption of growth regulatory effects and hence in the cancer-promoting ability of the mycotoxin. Detailed analyses of lipids in liver microsomal fractions of rats exposed to different dietary levels of FB1 over a period of 21 d indicated an increase in PC, PE, PI, an cholesterol (Chol). These changes decreased the PC/PE and increased the total phospholipid/Chol ratios. When considering FA content, the quantities of total FA increased (P < 0.05) in the major phospholipid fractions as a result of the increased phospholipid levels. However, when considering the relative levels (mg/100 mg of the total FA) of specific FA, the monounsaturated FA (16:1n-7 and 18:1n-9) and 18:2n-6 increased (P < 0.05), whereas the long-chain PUFA decreased (P < 0.05) in the main phospholipid fractions. Enzyme analyses indicated that the activity of the Delta6-desaturase was significantly reduced in liver microsomal preparations in a dose-dependent manner. An increase in the 20:3n-6/20:4n-6 ratio also suggested a decrease in the activity of the Delta5-desaturase. Disruption of microsomal lipid metabolism at different levels by FB1 could play an important role in the alteration of growth regulatory effects in the liver.

Gelderblom, W. C. A., J. P. Rheeder, et al. (2004). "Fumonisin contamination of a corn sample associated with the induction of hepatocarcinogenesis in rats - role of dietary deficiencies." Food and Chemical Toxicology 42(3): 471-479. ://000220164800016 A corn sample associated with a field outbreak of equine leukoencephalomalacia in Pennsylvania, USA, during 1983/1984 and induced hepatotoxic and hepatocarcinogenic effects when fed to male Fischer rats was analyzed mycologically and chemically for the presence of fumonisins (FB), hydrolysed FB derivatives and aflatoxins (AFB). Fusarium verticillioides was found to be the predominant fungal contaminant in the corn sample but Aspergillus flavus was also present. Trace amounts (0.1 mug/kg) of AFB(1) and AFB(2) and a total FB level of 33.5 mg/kg (FB1:FB2:FB3 ratio of 9:2.3:1) were found. No hydrolysed FB derivatives or AFG(1) and AFG(2) were detected. Based on the chemical stability of the fumonisins in different corn cultures of F. verticillioides kept at 4 degreesC over a period of 13-20 years, a level of approximately 55 mg/kg of total FB is estimated in the original corn sample. A possible role of certain dietary constituents such as the high protein content and deficiencies in certain micronutrients is evaluated to address differences in the organ-specific toxicity of FBI in rats using commercial, semi-purified, purified and corn-only diets. (C) 2004 Elsevier Ltd. All rights reserved.

Gelderblom, W. C. A., J. V. Seier, et al. (2001). "Toxicity of culture material of Fusarium verticillioides strain MRC 826 to nonhuman primates." Environmental Health Perspectives 109(2 supplement): 267-276. ://WOS:000168824500013 AND http://www.botanischergarten.ch/Bt/Gelderblom-Toxicity-Culture-Fumonisin-2001.pdf We conducted a chronic feeding study in vervet monkeys (Cercopithecus aethiops) over 13.5 years. The experimental design consisted of two dietary treatment groups, each including males and females, fed varying levels of culture material of Fusarium verticillioides (Sacc.) Nirenberg (= F. moniliforme Sheldon) strain MRC 826 mixed into their daily food ration. Two females were included as treatment controls. We conducted blood chemical analyses bimonthly and recorded all clinical signs during the course of the experiment. We took liver biopsies at various stages during the initial phase of the experiment. Several monkeys were terminated in extremis during the experiment. Detailed feed intake profiles were determined 5 years after the experiment began, and the fumonisin B (FB) mycotoxin content of the feed was determined during the final stages of the experiment. The apparent FB consumption patterns were related to changes observed in the biochemical parameters in the blood and urine, including the liver function enzymes and creatinine clearance as well as differential blood counts and sphingolipid levels in the serum and urine. An apparent no-effect threshold for kidney and liver damage is estimated to be between 0.11 and 0.18 mg FB/kg body weight (bw/day, which corresponds to a feed contamination level of between 8.21 and 13.25 mg FB/kg bw diet. Apart from the effects on the liver and kidney, a wide variety of parameters, including cholesterol and creatine kinase, were also adversely affected. Several blood parameters, including white and red blood cells, also significantly decreased in the treated animals. The serum sphinganine level and the sphingosine/sphinganine ratio, monitored toward the end of the experiment, significantly increased in both the low-dose and high-dose animals. The present study provides important information about the diversity of lesions induced by culture material of F. verticillioides in vervet monkeys and the dosage levels of fumonisins to be used in long-term studies in nonhuman primates.

Gelderblom, W. C. A., E. Semple, et al. (1992). "The Cancer-Initiating Potential of the Fumonisin-B Mycotoxins." Carcinogenesis 13(3): 433-437. ://A1992HJ82400019 The cancer-initiating potential of the fumonisin B (FB) mycotoxins produced by Fusarium moniliforme was screened in rat liver for their ability to induce rare hepatocytes with an acquired resistance to the mitoinhibitory effect of 2- acetylaminofluorene (2-AAF). Two different initiating protocols were used: a feeding regimen during which FB1 was fed at a dietary level of 0.1% for 26 days, and another where single or multiple doses of FB1 and FB2 (varying from 200 to 50 mg/kg) were administered (by gavage) to hepatectomized rats. In both cases promotion was effected by a 2- acetylaminofluorene/carbontetrachloride treatment. Cancer initiation was only obtained after the prolonged feeding regimen, indicating that the fumonisins are poor cancer initiators. FB1 and FB2 also lack genotoxic effects in the in vivo and in vitro DNA repair assays in primary hepatocytes. Although FB1 primarily affects the liver, it is not very cytotoxic to primary hepatocytes when compared to aflatoxin B1.

Gelderblom, W. C. A., C. M. Smuts, et al. (1996). "Effect of fumonisin B-1 on protein and lipid synthesis in primary rat hepatocytes." Food and Chemical Toxicology 34(4): 361-369. ://A1996UJ87300005 The effect of fumonisin B-1 (FB1) on protein and lipid synthesis was evaluated in primary rat hepatocytes. FB1 did not affect incorporation of [H-3]leucine into hepatocytes at either non-toxic (150 mu M) or cytotoxic (500 mu M) concentrations indicating that proc-in synthesis was not affected. However, FB1 significantly (P < 0.01 to P < 0.0001) inhibited incorporation of [C-14]palmitic acid into hepatocyte cultures implying that lipid synthesis was altered. Incorporation of the radiolabel was significantly (P < 0.05 to P < 0.0001) lowered in triacylglycerol (TAG) and sphingomyelin fractions and increased in phosphatidylcholine (PC) and phosphatidylethanolamine (PEA) in both FB1 concentrations. The incorporation pattern of [C-14]palmitic acid closely resembles the changes in phospholipid levels in the treated cells. The sphingolipid, sphinganine (Sa), was significantly (P < 0.0001) increased in treated cells but there was no significant difference between the toxic and non-toxic dose levels implying that the increased Sa level alone is not responsible for the in vitro toxicity. FB1 significantly (P < 0.01 to P < 0.001) decreased the level of free cholesterol within the cell, resulting in an increased PC:cholesterol ratio suggesting a more rigid membrane structure. Subsequent studies on the fatty acid (FA) profiles in PC and the neutral lipid, TAG, indicated that FB1 significantly (P < 0.05 to P < O.0001) increased the levels of the polyunsaturated FAs C18:2n-6 and C20:4n-6 at both concentrations. The FB1-induced changes to cellular membranes, specifically those related to FA changes in the major membrane phospholipids, and the altered FA content of the hepatocytes are likely to be key events in explaining the cytotoxic effects and altered growth responses induced by fumonisins in primary hepatocytes. (C) 1996 Elsevier Science Ltd. All rights reserved.

Gelderblom, W. C. A., C. M. Smuts, et al. (1997). "Effect of fumonisin B-1 on the levels and fatty acid composition of selected lipids in rat liver in vivo." Food and Chemical Toxicology 35(7): 647-656. ://A1997XU58200002 The modulating role of fumonisin B-1 (FB1) on lipid biosynthesis was evaluated in a shortterm (21 day) experiment using male Fischer rats fed high dietary levels (50, 100 and 250 mg FB1/kg) and in a long-term (2 yr) experiment using male ED IX rats fed low dietary levels (1, 10 and 25 mg FB1/kg) of FB1. The total serum and liver cholesterol was significantly (P < 0.01) increased in the rats fed 250 mg FB1/kg diet for 21 days, while the liver phospholipids, sphingomyelin and phosphatidylethanolamine (PE) were significantly decreased (P < 0.01) and increased (P < 0.05), respectively. In the long-term study, only PE was significantly (P < 0.05) increased in all the FBI-treated animals. Fatty acid (FA) analysis of PE indicated that C18:2n-6 was significantly increased (P < 0.05 to P < 0.01) in the FB1-treated rats of the short-term study, while it was markedly (not significantly) increased in phosphatidylcholine (PC). The same pattern was observed in the PC and PE fractions of the liver of the FB1-treated rats from the long-term studies, but the changes were not significant due to the small number (three rats per group) of rats analysed. The levels of C22:5n-6 and C22:6n- 3 were also markedly decreased and increased respectively in the 10 and 25 mg FB1/kg-treated groups. When the FAs were determined in the total lipids in a larger number of rats (four to six animals per group) the level of C18:2n-6 was significantly increased in the 10 (P < 0.01) and 25 (P < 0.05) mg FB1/kg-treated groups. Similar effects were noticed in plasma PC with respect to the C18:2n-6 and C22:5n-6 in both the long- and short-term treated groups, except that C20:4n-6 was also lower in both cases. The total n-6 FAs and polyunsaturated FAs were significantly (P < 0.01) and markedly reduced in PC and PE, respectively, of the rats fed the 250 mg FB1/kg diet. In the long-term experiment the n-6/n-3 ratio was significantly (P < 0.01) decreased in PE and markedly lowered in PC due to a significant (P < 0.05) increase in the n-3 FAs of both phospholipid fractions. The sphinganine/sphingosine ratio was significantly (P < 0.05) altered in the liver of the rats fed the 100 and 250 mg FB1/kg diets for 21 days, while in the long- term study no significant changes were noticed in either the liver or sera. The present data indicate that FB1 affects lipid biosynthesis in rat liver and plasma differently, depending on the dietary level and duration of treatment. Alterations to the n-3 and n-6 FA biosynthetic pathways, detected in rats fed relatively low dietary levels of FB1, are likely to be important mediators for FB1- induced effects on hepatocyte cell proliferation. (C) 1997 Elsevier Science Ltd.

Gelderblom, W. C. A., S. D. Snyman, et al. (1996). "The cancer-promoting potential of fumonisin B-1 in rat liver using diethylnitrosamine as a cancer initiator." Cancer Letters 109(1-2): 101-108. ://WOS:A1996VZ69800013 AND http://www.botanischergarten.ch/Bt/Gelderblom-Cancer-Promoting-1996.pdf

Gelderblom, W. C. A., S. D. Snyman, et al. (1995). "Mitoinhibitory Effect of Fumonisin B-1 on Rat Hepatocytes in Primary Culture." Carcinogenesis 16(3): 625-631. ://A1995QP09300029 The inhibitory effect of fumonisin B-1 (FB1) on epidermal growth factor (EGF)-induced DNA synthesis in primary rat hepatocytes was investigated by monitoring the incorporation of [H-3]thymidine in the DNA. A pulse-labelling technique was adapted to determine the incorporation of the radioactivity in the DNA (S-phase) quantitatively, FB1 inhibits the EGF-induced DNA synthesis up to 90% when incorporated at concentrations of 150 to 300 mu M for a period of 44 h. A continued presence of FB1 is required to exhibit this inhibition as (i) the subsequent removal of FB1 resulted in a reversal of the effect, (ii) a higher stimulatory response in EGF-treated hepatocytes was found when the exposure period of hepatocytes to FB1 was reduced, and (iii) pretreatment of hepatocytes with FB1 only slightly reduced (not significantly) DNA synthesis induced by EGF. Whilst the growth inhibitory effect of FB1 was not associated with a cytotoxic effect, binding studies using [I- 125]EGF indicated that the growth factor-receptor interaction was not altered. No relationship was found between the disruption of the sphingolipid biosynthesis by FB1 and (i) the mitoinhibitory effect on the EGF response and (ii) the cytotoxicity of FB1 in primary hepatocytes.

Gembeh, S. V., R. L. Brown, et al. (2001). "Identification of chemical components of corn kernel pericarp wax associated with resistance to Aspergillus flavus infection and aflatoxin production." Journal of Agricultural and Food Chemistry 49(10): 4635-4641. ://000171615100019 Kernel pericarp wax of the corn breeding population GT-MAS:gk has been associated with resistance to Aspergillus flavus infection and aflatoxin production. GT-MAS:gk wax, previously compared to waxes of three susceptible genotypes, was presently compared to wax of A different, and more numerous, group of susceptible lines. Wax separation by TLC confirmed previous findings, demonstrating a unique GT-MAS:gk band and a unique "susceptible" band. Only GT-MAS:gk wax inhibited the growth of A. flavus; however, no association was established, as before, between kernel wax abundance and resistance. Gas chromatography-mass spectroscopy (GC-MS) analysis of kernel whole wax showed a higher percentage of phenol-like compounds in wax from GT-MAS:gk than in waxes from the susceptible lines. The GT-MAS:gk unique band contained phenol-like compounds and ethyl-hexadecanoate; butyl-hexadecanoate was preeminent in most of the "susceptible bands". Alkylresorcinol (phenolic compounds) content was dramatically higher in GT-MAS:gk wax than in the wax of susceptible lines. An alkylresorcinol, 5- methylresorcinol, also inhibited in vitro growth of A. flavus. These and other phenolic compounds may contribute to kernel wax inhibition of A. flavus infection/aflatoxin production. Further investigation is needed to confirm a role for them in. GT- MAS:gk resistance.

GemechuHatewu, M., K. L. Platt, et al. (1997). "Metabolic activation of aflatoxin B-1 to aflatoxin B-1-8,9- epoxide in woodchucks undergoing chronic active hepatitis." International Journal of Cancer 73(4): 587-591. ://A1997YG99200021 Chronic hepatitis B virus infection as well as consumption of food contaminated with the mycotoxin aflatoxin B-1 are considered to be 2 major risk factors for the development of primary liver cancer in humans, Furthermore, epidemiological surveys indicate that hepatitis B virus and aflatoxin B-1 might act synergistically to induce primary liver cancer. In the present study, we have tested the hypothesis that the metabolic activation of aflatoxin B-1 to aflatoxin B-1-8,9-epoxide, the ultimate mutagenic and carcinogenic mycotoxin metabolite, is enhanced in an experimental model of chronic hepatitis using woodchucks, chronically infected with the woodchuck hepatitis virus. Woodchuck liver microsomes were incubated with radiolabeled aflatoxin B-1, the resulting aflatoxin B-1- 8,9- epoxide was trapped as a glutathione conjugate and its formation rate was determined by a reversed-phase HPLC analysis. In woodchuck hepatitis virus-positive woodchucks, activation of aflatoxin B-1 to aflatoxin B-1-8,9-epoxide was reduced when compared to woodchuck hepatitis virus-free animals, and the extent of the reduction was dependent on the severity of the hepatitis, Hence, at least in woodchucks, a chronic hepadnaviral infection does not lead to an enhanced activation of aflatoxin B-1. (C) 1997 Wiley-Liss, Inc.

Gong, Y. Y., S. Egal, et al. (2003). "Determinants of aflatoxin exposure in young children from Benin and Togo, West Africa: the critical role of weaning." International Journal of Epidemiology 32(4): 556-562. ://000184783500019 Background Dietary exposure to high levels of the fungal toxin, aflatoxin, occurs in West Africa, where long-term crop storage facilitates fungal growth. Methods We conducted a cross- sectional study in Benin and Togo to investigate aflatoxin exposure in children around the time of weaning and correlated these data with food consumption, socioeconomic status, agro- ecological zone of residence, and anthropometric measures. Blood samples from 479 children (age 9 months to 5 years) from 16 villages in four agro-ecological zones were assayed for aflatoxin-albumin adducts (AF-alb) as a measure of recent past (2-3 months) exposure. Results Aflatoxin-albumin adducts were detected in 475/479 (99%) children (geometric mean 32.8 pg/mg, 95% CI: 25.3-42.5). Adduct levels varied markedly across agro- ecological zones with mean levels being approximately four times higher in the central than in the northern region. The AF-alb level increased with age up to 3 years, and within the 1-3 year age group was significantly (P=0.0001) related to weaning status; weaned children had approximately twofold higher mean AF-alb adduct levels (38 pg AF-lysine equivalents per mg of albumin [pg/mg]) than those receiving a mixture of breast milk and solid foods after adjustment for age, sex, agro-ecological zone, and socioeconomic status. A higher frequency of maize consumption, but not groundnut consumption, by the child in the preceding week was correlated with higher AF-alb adduct level. We previously reported that the prevalence of stunted growth (height for age Z-score HAZ) and being underweight (weight for age Z-score WAZ) were 33% and 29% respectively by World Health Organziation criteria. Children in these two categories had 30-40% higher mean AF-alb levels than the remainder of the children and strong dose- response relationships were observed between AF-alb levels and the extent of stunting and being underweight. Conclusions Exposure to this common toxic contaminant of West African food increases markedly following weaning and exposure early in life is associated with reduced growth. These observations reinforce the need for aflatoxin exposure intervention strategies within high-risk countries, possibly targeted specifically at foods used in the post-weaning period.

Gonzalez, H. H. L., E. J. Martinez, et al. (1999). "Natural co-occurrence of fumonisins, deoxynivalenol, zearalenone and aflatoxins in field trial corn in Argentina." Food Additives and Contaminants 16(12): 565-569. ://000084240900007 Cool samples collected from the main production ar ea in Argentina in 1995 were surveyed for the natural occurrence of Fusarium mycotoxins and aflatoxins. Fumonisins B-1, B-2 and B-3 and zearalenone were found in all samples. A positive relationship was found between fumonisins B-1, B-2 and B-3, B-1 and B-3, and B-2 and B-3. Deoxynivalenol and aflatoxins were not detected. Mycological survey has also revealed the predominance of Fusarium moniliforme. This is the first report on the simultaneous occurrence of fumonisins and =earalenone in corn from the main production area in Argentina.

Gqaleni, N., J. E. Smith, et al. (1996). "The production of cyclopiazonic acid by Penicillium commune and cyclopiazonic acid and aflatoxins by Aspergillus flavus as affected by water activity and temperature on maize grains." Mycopathologia 136(2): 103-108. ://A1996XH01100007

Greene-McDowelle, D. M., B. Ingber, et al. (1999). "The effects of selected cotton-leaf volatiles on growth, development and aflatoxin production of Aspergillus parasiticus." Toxicon 37(6): 883-893. ://000079866300004 The fungi Aspergillus flavus and Aspergillus parasiticus produce the hepatocarcinogenic, secondary metabolites, aflatoxins, in cottonseed, corn, peanuts and treenuts. Results have shown that aflatoxigenic strains of A. flavus and A. parasiticus grown in the presence of specific cotton-leaf volatiles exhibit alterations in aflatoxin production accompanied by variations in growth of the fungi. In this study, two alcohols (3-methyl-1-butanol (3-MB) and nonanol) and two terpenes (camphene and limonene) were chosen as representative cotton-leaf volatiles based on the effects they had on fungal growth and/ or aflatoxin production in previous investigations. The morphological effects of volatile exposure were examined in correlation with fungal growth and aflatoxin production. 3-MB-treated samples exhibited a decrease in fungal radial growth which was directly proportional to the volatile dosage. Additionally, 3-MB treatment resulted in loss of mycelial pigmentation and a decrease in sporulation. Limonene and camphene-treated samples yielded negligible differences in radial growth and morphology when compared to unexposed controls. In addition to radial growth inhibition, samples grown in the presence of nonanol demonstrated uniquely aerial hyphae. In comparison to an unexposed control, aflatoxin production increased in cultures exposed to 3-MB but decreased when exposed to the other three volatiles studied. Published by Elsevier Science Ltd.

Gressel, J., A. Hanafi, et al. (2004). "Major heretofore intractable biotic constraints to African food security that may be amenable to novel biotechnological solutions." Crop Protection 23(8): 661-689. http://www.botanischergarten.ch/Mycotoxins/Gressel-African-bioconstraints.pdf The input costs of pesticides to control biotic constraints are often prohibitive to the subsistence farmers of Africa and seed based solutions to biotic stresses are more appropriate. Plant breeding has been highly successful in dealing with many pest problems in Africa, especially diseases, but its limited to the genes available within the crop genome. Years of breeding and studying cultural practices have not always been successful in alleviating many problems that biotechnology may be able to solve. We pinpoint the major intractable regional problems as: (1) weeds: parasitic weeds (Striga and Orobanche spp.) throughout Africa; grass weeds of wheat (Bromus and Lolium) intractable to herbicides in North Africa; (2) insect and diseases: stem borers and post-harvest grain weevils in sub-Saharan Africa; Bemesia tabaci (white fly) as the vector of the tomato leaf curl virus complex on vegetable crops in North Africa; and (3) the mycotoxins: fumonisins and aflatoxins in stored grains. Abiotic stresses may exacerbate many of these problems, and biotechnological alleviations of abiotic stress could partially allay some predicaments. Some of these constraints are already under study using biotechnological procedures, but others may require longer-term research and development to alleviate the problems. Despite the huge impacts of post-harvest weevils and of mycotoxins in grains, these issues had not been given high priority in national biotechnological programs, possibly due to a lack of knowledge of their immensity. The need for public sector involvement is accentuated for cases where immediate profits are not perceived (e.g. lowering mycotoxin levels in farmer utilized grain, which does not increase yield) but where the public weal will gain, and will be invaluable, especially where the private sector supplies genes already isolated. (C) 2004 Elsevier Ltd. All rights reserved.

Groopman, J. D., T. W. Kensler, et al. (2008). "Protective interventions to prevent aflatoxin-induced carcinogenesis in developing countries." Annual Review of Public Health 29: 187-203. ://WOS:000255349400015 AND http://www.botanischergarten.ch/Bt/Groopman-Protective-Interventions-2008.pdf The public health impact of aflatoxin exposure is pervasive in economically developing countries; consequently, we need to design intervention strategies for prevention that are practicable for these high-risk populations. The adverse health consequences of aflatoxins in populations are quite varied, eliciting acute effects, such as rapid death, and chronic outcomes, such as hepatocellular carcinoma. Furthermore, a number of epidemiological studies describe a variety of general adverse health effects associated with aflatoxin, such as impaired growth in children. Thus, the magnitude of the problem is disseminated across the entire spectrum of age, gender, and health status in the population. The aflatoxins multiplicatively increase the risk of liver cancer in people chronically infected with hepatitis B virus (HBV), which illustrates the deleterious impact that even low toxin levels in the diet can pose for human health. Thus other aflatoxin interactions, which likely contribute to the diesease burden, still remain to be identified. Therefore, many diverse and appropriate strategies for disease prevention are needed to decrease the incidence of aflatoxin carcinogenesis in developing countries.

Guo, B. Z., R. L. Brown, et al. (1998). "Protein profiles and antifungal activities of kernel extracts from corn genotypes resistant and susceptible to Aspergillus flavus." Journal of Food Protection 61(1): 98-102. ://WOS:000071766500017 Mechanisms of resistance to infection by the fungus Aspergillus flavus and accumulation of aflatoxin were studied in kernels of resistant (GT-MAS:gk, Mp420) and susceptible (Pioneer 3154, Deltapine G-4666) corn genotypes. Proteins from kernel extracts of corn genotypes were analyzed by several methods of polyacrylamide gel electrophoresis. Consistent differences in protein profiles were detected among genotypes. Several proteins were unique to or present in greater concentration in resistant genotypes, whereas others were present only in susceptible genotypes. Extracts of resistant kernels showed markedly greater antifungal activity against A. flavus than did susceptible kernel extracts. Results from the present study suggest a role for kernel proteins in resistance to A. flavus infection and aflatoxin contamination in corn genotypes GT-MAS:gk and Mp420.

Guo, B. Z., A. Butron, et al. (2002). "Restriction fragment length polymorphism assessment of the heterogeneous nature of maize population GT-MAS : gk and field evaluation of resistance to aflatoxin production by Aspergillus flavus." Journal of Food Protection 65(1): 167-171. ://000173281900025 Aflatoxin, produced by Aspergillus flavus, is one of the most toxic and carcinogenic substances known and contaminates many agricultural commodities such as corn, peanuts, cottonseed, and tree nuts, The challenge to breeders/plant pathologists is to identify lines that have resistance to aflatoxin production. Maize population GT-MAS:gk has been identified and released as a germplasm with resistance to aflatoxin contamination. In the present study, we assessed genetic divergence in the GT-MAS:gk Population using restriction fragment length polymorphism (RFLP) DNA markers to survey 11 selfed inbred lines and conducted field evaluations for the dissimilarities in aflatoxin production among these inbred lines in comparison with a sister population. GT- MAS;pw.nf, The 11 selfed inbred lines were assayed for DNA polymorphism using a 113 RFLP markers in 10 linkage groups covering 1,518.2 centimorgans (cM; unit of gene or chromosome size), Considerable variation among the inbreds was detected with RFLP markers, of which 42 probe- enzyme combinations gave 102 polymorphic bands. Cluster analysis based on genetic similarities revealed associations and variations among the tested lines. Three polymorphic groups were distinguished by cluster analysis. Two years of field evaluation data showed that aflatoxin concentrations among the lines were significantly different in both years (P < 0.001). Maturity data were also different. Thus, this study demonstrates that the maize population GT-MAS:gk is heterogeneous and that individuals may be different in resistance to A. flavus infection and aflatoxin production, Therefore, the most resistant lines should be inbred to increase homogeneity, and resistance should be confirmed through progeny testing.

Guo, B. Z., R. G. Li, et al. (2001). "Genetic variation within maize population GT-MAS : gk and the relationship with resistance to Aspergillus flavus and aflatoxin production." Theoretical and Applied Genetics 103(4): 533-539. ://000171240000007 Aspergillus flavus (Link:Fr.) infection and aflatoxin contamination of maize (Zea mays L.) grain are an extremely serious problem. Maize genotypes resistant to A. flavus attack are needed. Maize breeders and plant pathologists must identify resistance sources and incorporate resistance into adapted breeding material. Maize population GT-MAS:gk has been released for use as a resistance source. In this study, we surveyed the genetic variation in this population and made the breeders/plant pathologists aware of the heterogeneous nature in this maize population by using RAPD analysis and correlated the RAPD marker association with the resistance to A. flavus and aflatoxin production. Of 40 RAPD primers, only 15 gave sufficient numbers of reproducible and readily scored polymorphic bands suggesting that this population was highly homogeneous. However, genetic distances, ranging from 0.08 to 0.28 and averaging 0.17, suggest that there is variation within the population. Cluster analysis distinguished three major polymorphic groups. Laboratory bioassay revealed that group I contained the most resistant individuals, i.e., those with less aflatoxin production. Group Il had the least resistance, and group III was intermediate. This study showed that the maize population GT- MAS:gk is heterogeneous and individuals are different in resistance to A. flavus and aflatoxin production. Resistance should be confirmed through progeny testing before further development. The RAPD marker OPX-04, which may be associated with the resistance trait, has been cloned and further characterization will be pursued.

Guo, B. Z., J. S. Russin, et al. (1996). "Resistance to aflatoxin contamination in corn as influenced by relative humidity and kernel germination." Journal of Food Protection 59(3): 276-281. ://A1996UA87500010

Guo, B. Z., J. S. Russin, et al. (1995). "Wax and Cutin Layers in Maize Kernels Associated with Resistance to Aflatoxin Production by Aspergillus- Flavus." Journal of Food Protection 58(3): 296-300. ://A1995QT48300013 Thirteen maize hybrids and one maize population, MAS:gk, were screened for susceptibility to aflatoxin production by Aspergillus flavus. Marked differences in aflatoxin B1 production were detected among the maize genotypes tested. Most commercial hybrids consistently supported high levels of aflatoxin accumulation. Aflatoxin levels did not differ between intact and wounded kernels of these genotypes. However, different results were obtained from 4 of the 13 hybrids and the maize population MAS:gk. Levels of aflatoxin accumulation in intact kernels of these genotypes were lower than in the previous susceptible group of genotypes. In addition, aflatoxin levels were higher in wounded than in intact kernels. MAS:gk not only supported the lowest levels of aflatoxin production in intact kernels, but aflatoxin levels in endosperm-wounded kernels also were significantly lower in MAS:gk than in wounded kernels of all tested hybrids. Treatment with KOH to remove cutin from intact kernels prior to inoculation with A. flavus effected substantial increases in aflatoxin accumulation in MAS:gk, but only marginal increases in the susceptible hybrid Pioneer 3154. Removing wax from the surface of MAS:gk kernels greatly increased the susceptibility of this genotype to aflatoxin accumulation. When wax removal was combined with treatment with potassium hydroxide (KOH) or purified cutinase, aflatoxin levels in kernels were equal to those in wounded control kernels in both genotypes. These results indicated that wax and cutin layers of maize kernel pericarps may play a role in resistance to aflatoxin accumulation in MAS:gk and some other genotypes. However, results suggest further that resistance in MAS:gk also may be due to other preformed compounds as well.

Gutema, T., C. Munimbazi, et al. (2000). "Occurrence of fumonisins and moniliformin in corn and corn- based food products of US origin." Journal of Food Protection 63(12): 1732-1737. ://000165791200018 Food-grade corn and corn-based food products intended for human consumption were analyzed for the incidence and levels of fumonisin B-1 (FB1), fumonisin B-2 (FB2), moniliformin, and Fusarium molds. A total of 100 food-grade commercial corn samples were obtained from two corn processing companies at five different locations in the United States. Seventy-one percent of the samples contained FB1 with concentrations ranging from 43 to 1,642 mug/kg. None of the samples contained FB2. Fifty percent of the samples contained moniliformin with concentrations ranging from 26 to 774 mug/kg. All samples were infected by Fusarium molds, and the infection rates ranged from 8 to 88%. Thirty-four samples of corn-based food products were purchased from supermarkets in Arizona, California, Nebraska, and Ohio. Sixty-five percent of the samples contained FB1, ranging in concentrations from 28 to 2,679 mug/kg. FB2 was detected in 29% of the samples with concentrations ranging from 30 to 797 mug/kg. Sixty-eight percent of the samples contained moniliformin with concentrations ranging from 31 to 858 mug/kg. Sixty-two percent of the samples contained viable Fusarium mold propagules ranging from 9.5 x 10(1) to 5.5 x 10(5)/g. The simultaneous occurrence of FB1 and moniliformin was observed in 34% of corn samples and 53% of corn-based food products. This study has shown co-occurrence of fumonisins and moniliformin in food-grade corn and corn-based foods that indicates a risk of simultaneous exposure of consumers to both toxins.

Hadiani, M. R., H. Yazdanpanah, et al. (2003). "Survey of the natural occurrence of zearalenone in maize from northern Iran by thin-layer chromatography densitometry." Food Additives and Contaminants 20(4): 380-385. ://000182875000010 AND http://www.botanischergarten.ch/Bt/Hadiani-Survey-Zearalenone-2003.pdf

During September 2000, forty samples of preharvest maize from the province of Mazandaran, north Iran, were randomly collected. Samples were analysed for zearalenone (ZEA) by a thin-layer chromatograpy (TLC) method (AOAC Official Method). ZEA was extracted with chloroform, purified through a chromatographic column containing silica gel, separated on a TLC plate and quantified by densitometry. The analytical method was validated and was adequately reliable and sensitive. The mean recovery rate of ZEA from spiked samples was 92%. The absolute amount of ZEA standard detectable on a TLC plate was 20 ng, giving a limit of detection (LOD) of 100 ng g(-1). In some samples, it was shown that a. atoxins interfere with ZEA. Therefore, to remove this interference, the TLC mobile phase was changed. Data revealed that three of 40 (7.5%) maize samples contained ZEA in the range 100-212 ng g(-1), with a mean of 141 +/- 51 ng g(-1). This study, which is the first report of ZEA occurrence in Iranian maize, showed that the ZEA level in maize of Mazandaran province was lower than maximum limit for this mycotoxin in Iran.

Hamblin, A. M. and D. G. White (2000). "Inheritance of resistance to aspergillus ear rot and aflatoxin production of corn from Tex6." Phytopathology 90(3): 292-296. ://000085499400013 The inheritance of resistance to Aspergillus ear rot and anatoxin production in corn (Zen mays L.) caused by Aspergillus flavus was studied in progeny derived from crosses between the resistant corn inbred cv. Tex6 and susceptible inbred cvs. B73 and Mo17. From 1994 to 1996, plant generations included were the P-1 (susceptible B73 or Mo17), P-2 (resistant Tex6), F-1, F-2, F-3, BCP1, BCP1- selfed, and BCP2. The BCP2-selfed generation was added in 1995 and 1996 for the B73 x Tex7 cross. Primary ears were pinboard inoculated and evaluated for Aspergillus ear rot severity. F-1 means deviated from the midparent value toward resistance for anatoxin production and toward susceptibility for ear rot in both crosses. Analyses of generation means indicate that additive gene action was most important in the resistance to both ear rot and anatoxin production in the B73 x Tex6 cross. Mo17 was somewhat resistant to both traits, so resistance from Tex6 was not well defined in this cross. Broad-sense heritabilities for ear rot and anatoxin production were 58 and 63% for Mo17 x Tex6, and 66 and 65% for B73 x Tex6. Narrow-sense heritabilities for ear rot and anatoxin production were 39 and 45% for B73 x Tex6. It is estimated that one cycle of selection for resistance within B73 x Tex6 F-3 families would reduce the percentage of ear rot severity by 8.5% and anatoxin concentration by 19 ng/g.

Hammond, B. (2004). A review of the food/feed safety and benefits of Bacillus thuringiensis protein containing insect-protected crops. Agricultural Biotechnology: Challenges and Prospects. Washington, AMER CHEMICAL SOC. 866: 103-123. ://000189476000008 Infestation of agricultural crops by insect pests has been traditionally managed through the use of chemical insecticides. An alternative method to control insect pests has been the introduction of insecticidal proteins from Bacillus thuringiensis into agricultural crops by genetic engineering. The introduced insect control proteins have an exemplary safety record having been safely used in agriculture for 40 years as the active ingredients of microbial pesticides. Insect- protected biotech crops control a variety of insect pests such as corn borers, cotton bollworms, and Colorado potato beetles. Season long protection of the crop improves yield and reduces reliance on traditional chemical insecticides. Protection of corn plants against insect damage reduces infection by certain fungal pathogens that produce fumonisin mycotoxins that are toxic to various species.

Hammond, B., K. Campbell, et al. (2006). The Use of GMO as a prevention strategy for mycotoxin formation. The Mycotoxin Factbook: Food and Feed Topics D. Barug, D. Bhadnagar, H. P. Van Egmond and J. W. Van Der Kamp. Wageningen, NL, Wageningen Academic Publishers; 1st edition (October 22, 2006): 384.

A variety of environmental stress factors increase susceptibiiity of corn plants to infection with various fungi that produce mycotoxins. These stress factors include insect damage, heat and drought stress, nitrogen deficiency and genetic susceptibility For example, insect feeding injures corn kernels, creating ports of entry for fungi that produce ear rot and mycotoxins. Biocechnology is helping to provide season-long protection of corn plants (Bt corn) against corn borer damage through the introduction of insect control proteins derived from Bacillus tburirrgiensis. Reduction of insect feeding damage in Bt corn has led to lower contamination with fumonisin mycotoxins in most locations it has been tested around the world. Biotechnology is also being used to develop healthier corn plants by making them less susceptible to drought stress, increasing nitrogen utilisation, and protecting plants against a wider \lariecy of insect pests that feed on the ears, stalks and roots. In the future, combining these traits will further improve yield and should reduce corn plant susceptibility to environmental stress factors that concribute to mycocoxin contamination in the field.

Hammond, B., K. Campbell, et al. (2008). "Opportunities for Mycotoxin Reduction in Maize Using Biotechnology." Food Contaminants: Mycotoxins and Food Allergens 1001: 109-124. ://WOS:000268886600006 A variety of environmental stress factors increase susceptibility of corn plants to infection with various fungi that produce mycotoxins. These stress factors include insect damage, heat and drought stress, nitrogen deficiency, and genetic susceptibility. For example, insect feeding injures corn kernels, creating ports of entry for fungi that produce ear rot and mycotoxins. Biotechnology is helping to provide season-long protection of corn plants (Bt corn) against corn borer damage through the introduction of insect control proteins derived from Bacillus thuringiensis. Reduction of insect feeding damage in Bt corn has led to lower contamination with fumonisin mycotoxins in most locations where it has been tested around the world. Biotechnology is also being used to develop healthier corn plants by making them less susceptible to drought stress, increasing nitrogen utilization, and protecting plants against a wider variety of insect pests that feed on the ears, stalks and roots. In the future, combining these traits will further improve yield and should reduce corn plant susceptibility to environmental stress factors that contribute to mycotoxin contamination in the field.

Hammond, B., K. Campbell, et al. (2001). "Reduction of fumonisin levels in the grain of Bt maize." Phytopathology 91(6 Supplement): S36. ://BIOSIS:PREV200100404148

Hammond, B., K. Campbell, et al. (2001). "Reduction of fumonisin levels in the grain of Bt maize, abstract." Phytopathology 91(6 Supplement, short abstract): S36. ://BIOSIS:PREV200100404148 Insect damage to maize can lead to increased infection by mycotoxigenic fungi such as Fusarium verticillioides (Sacc.) Nirenberg, which produces fumonisins. Protection from insect damage through plant expression of Cry proteins from the bacterium Bacillus thuringiensis reduces fungal infection and fumonisin levels in grain (Munkvold, Hellmich and Rice, 1999, Dowd, 2000). This has been confirmed in other trials. In northern Italy, Bt maize had apprx3 fold reduction in fumonisin levels when compared to non Bt hybrids (averaged across 30 field sites (1999). Similar reductions were observed in southwest France and Spain (1999). In these trials, Bt maize had lower insect damage and fungal infection. In the U.S., fumonisin levels were apprx2 fold lower in Bt maize grown at 55 sites in 11 states (2000). These trials were conducted under natural insect infestation. In trials conducted using manual insect infestation (15 sites in 10 states) fumonisin levels were reduced apprx5 fold (2000).

Hammond, B., K. Campbell, et al. (2002). "Reduction of fungal and fumonisin levels in Bt. corn." Mycopathologia 155(1-2): 22. ://BIOSIS:PREV200300181828

Hammond, B. G., K. W. Campbell, et al. (2004). "Lower fumonisin mycotoxin levels in the grain of Bt corn grown in the United States in 2000- 2002." Journal of Agricultural and Food Chemistry 52(5): 1390-1397. ://000220039800060 AND http://www.botanischergarten.ch/Bt/Hammond-lower-Fumonisin-2004.pdf Fumonisins were monitored in corn grain collected from Bt hybrids grown in 107 locations across the United States in 2000-2002. Bt corn hybrids contain the Cry1Ab protein from Bacillus thuringiensis that controls European corn borers and other stalk-boring pests. Fumonisin levels were frequently lower in grain from Bt hybrids grown in field trials under conditions of natural (FACT trials) or manual insect infestation (university trials). Over three years of FACT trials, there were 126/210 comparisons when fumonisin levels in grain from control hybrids were >2 ppm, exceeding U.S. FDA guidance levels of 2 ppm for human food. Grain from Bt hybrids was at or below 2 ppm of fumonisins for 58 of the 126 comparisons. The use of Bt hybrids can increase the percentage of corn grain that would be suitable for use in food and feed.

Harris, L. J., A. E. Desjardins, et al. (1999). "Possible role of trichothecene mycotoxins in virulence of Fusarium graminearum on maize." Plant Disease 83(10): 954-960. ://WOS:000082796100013 Trichothecene-producing and -nonproducing Fusarium graminearum strains were tested for their ability to cause Gibberella ear rot in field trials at two locations-Ottawa, Ontario, and Peoria, Illinois-in 1996. Maize ears were inoculated with wild-type or transgenic F. graminearum strains in which the trichothecene biosynthetic pathway had been disabled by the specific disruption of the trichodiene synthase gene and with a derivative revertant strain in which trichothecene production had been restored through recombination. A silk channel inoculation method was employed at both locations. In addition, a kernel puncture inoculation method was used at the Ontario location. Harvested maize ears were analyzed for visual disease severity, grain yield, deoxynivalenol (DON) concentration, and fungal biomass by quantitative polymerase chain reaction (PCR) and/or ergosterol quantitation. There was a significant correlation (r = 0.86) between data obtained from the two different methods of quantifying fungal biomass. The trichothecene-nonproducing strains were still pathogenic but appeared less virulent on maize than the trichothecene-producing progenitor and revertant strains, as assayed by most parameters. This suggests that the trichothecenes may act as virulence factors to enhance the spread of F. graminearum on maize.

Haschek, W. M., L. A. Gumprecht, et al. (2001). "Fumonisin toxicosis in swine: An overview of porcine pulmonary edema and current perspectives." Environmental Health Perspectives 109(2 supplement): 251-257. ://WOS:000168824500011 AND http://www.botanischergarten.ch/Bt/Haschek-Fumonisin-Toxicosis-2001.pdf Fumonisin toxicosis in swine was named porcine pulmonary edema (PPE) after outbreaks of a fatal disease in pigs fed Fusarium verticillioides (F. moniliforme)-contaminated corn screenings from the 1989 corn crop in lowa, Illinois, and Georgia. Pigs that died had severe pulmonary edema, which has not been identified in other species after exposure to fumonisins. The disease has been reproduced experimentally by feeding of naturally contaminated corn, F. verticillioides culture material, and by intravenous administration of fumonisin B-1 (FB1). Hepatic lesions consisting of apoptosis, necrosis, and hepatocyte proliferation also are observed. As in other species, alterations in clinical pathology reflect hepatic injury as well as elevated serum cholesterol concentration. In chronic studies, esophageal plaques, hyperplastic hepatic nodules, and right ventricular hypertrophy were found. In pigs, as in other species, fumonisin alters sphingolipid biosynthesis, with the greatest alterations in sphingosine and sphinganine concentrations in kidney, liver, lung, and heart. Our recent studies on fumonisin toxicosis in pigs have focused on immune effects and the pathogenesis of pulmonary edema. The specific immune system was not affected; however, FB1 inhibited phagocytosis and sphingolipid biosynthesis in pulmonary macrophages. Fumonisin induced an accumulation of membranous material in pulmonary capillary endothelial cells; this change appears specific to this cell type and to swine. In short-term cardiovascular studies, fumonisin decreased left ventricular dP/dt(max) (an index of cardiac contractility), mean systemic arterial pressure, heart rate, and cardiac output, and increased mean pulmonary artery pressure and pulmonary artery wedge pressure. These changes are compatible with the inhibition of L-type calcium channels by increased sphingosine and/or sphinganine concentration. Therefore, fumonisin-induced pulmonary edema in swine appears to result from acute left-sided heart failure mediated by altered sphingolipid biosynthesis.

Hawkins, L. K., G. L. Windham, et al. (2005). "Effect of different postharvest drying temperatures on Aspergillus flavus survival and aflatoxin content in five maize hybrids." Journal of Food Protection 68(7): 1521-1524. ://WOS:000230329900035 After harvest, maize is dried artificially to halt fungal growth and mycotoxin production while in postharvest storage. The process often limits harvest capacity and has been a frequent cause of seed injury. Higher drying temperatures could lead to shorter drying periods and faster turnover; however, there is often a deterioration of the physical grain quality, including increased breakage susceptibility and loss of viability. The goals of this study were to determine the effect of different postharvest drying temperatures on Aspergillus flavus and Fusarium verticillioides survival and aflatoxin content in maize and to determine the viability of the seed. Five corn hybrids varying in resistance to A. flavus were side needle-inoculated with A. flavus, harvested at physiological maturity, and dried at temperatures ranging from 40 to 70 degrees C. Kernels were evaluated for aflatoxin, stress cracks, germination, and kernel infection by A. flavus and a natural infestation of F. verticillioides. Drying temperature had no effects on aflatoxin concentration given the heat stability of the toxin. With increased temperatures from 40 to 70 degrees C, germination decreased significantly, from 96 to 27%, and stress cracks increased significantly (1.4 up to 18.7). At temperatures above 60 degrees C, F. verticillioides kernel infection was significantly reduced to less than 18%. At 70 degrees C, there was a significant reduction in A. flavus kernel infection, from 11 to 3%. This information is useful in determining a range of temperatures that can be used for drying seed when fungal infection, stress cracks, and seed viability are of interest.

Hawkins, L. K., G. L. Windham, et al. (2008). "Occurrence of aflatoxin in three maize (Zea mays L.) hybrids over 5 years in Northern Mississippi." Mycopathologia 165(3): 165-171. ://WOS:000254113300007 Aflatoxins are produced as secondary metabolites under conducive climatic conditions by Aspergillus flavus. The incidence of aflatoxin varies with environmental conditions, genotype, and location. An expanded understanding of the interaction of the plant, fungus, and weather conditions is needed to further elucidate the field infection process of maize by A. flavus and subsequent aflatoxin contamination. One of the problems in evaluating maize hybrids for resistance to kernel infection and aflatoxin contamination is identifying a time period and environmental conditions that are most advantageous. Three maize genotypes (Pioneer Brand 3223, Mo18W x Mp313E, and Mp313E x Mp420) were evaluated from 1998 to 2002 in response to A. flavus inoculation and aflatoxin contamination and weather conditions favorable for aflatoxin contamination were identified. The highest aflatoxin levels were observed in 1998 and 2000 (1186 and 901 ng g(-1); P < 0.0001); while the lowest levels were detected in 1999 (39 ng g(-1)). Pioneer 3223 had significantly higher levels (1198 ng g(-1)) than Mp313E x Mp420 (205 ng g(-1)), and Mo18W x Mp313E (161 ng g(-1); P < 0.0001). The hybrids had six weather-related variables in common that were positively correlated with aflatoxin accumulation. Four of these occurred during 65-85 days after planting and were temperature-related. These results suggest that regardless of the hybrid's maturity or physiological development, the time from 65 to 85 days after planting may be indicative of a period of stress which leads to greater aflatoxin accumulation at harvest.

Hell, K., K. F. Cardwell, et al. (2003). "Relationship between management practices, fungal infection and aflatoxin for stored maize in Benin." Journal of Phytopathology 151(11-12): 690-698. ://000186875300020 This study relates preharvest and harvest practises to postharvest quality of maize in Benin, West Africa. Fungal infection and aflatoxin levels were evaluated in 300 farmers' stores in four agro-ecological zones over 2 years (1993-1995), at the beginning of storage (sample A) and 6 months later (sample B). Aspergillus flavus infected 10-20% of the kernels in sample A (1993-1994). In sample B, 54-79% of the kernels were infected with A. flavus. In 1994-1995, A. flavus infection was higher in sample A (27-47%) than B (8-26%). Fusarium species were found in 38-58% of the kernels in sample A in both years, but decreased slightly to 29-51% in sample B. Significant agroecozonal effects existed within sampling, but were not consistent between samplings and years. Of the total number of samples collected (744), 38.8% were found to be aflatoxin-positive, with an average of 105 parts per billion (ppb) and 60% of the aflatoxin-positive samples having a contamination approximately 20 ppb, the intervention level recommended by the World Health Organization. Factors associated with increased aflatoxin were: planting local maize varieties in southern Benin, intercropping with cowpea, groundnut, or cassava, use of urea-fertilizer, damage to maize in the field, prolonged harvesting, long drying periods in the field, and winnowing. Practices that reduced aflatoxin contamination were: planting improved varieties in northern Benin, mixed cropping with vegetables, use of NPK-fertilizer, drying of harvested cobs for 60-90 days, drying ears without the husk, sorting out of poor quality ears.

Hell, K., K. F. Cardwell, et al. (2000). "The influence of storage practices on aflatoxin contamination in maize in four agroecological zones of Benin, west Africa." Journal of Stored Products Research 36(4): 365-382. ://000088457200004 and http://www.botanischergarten.ch/Mycotoxins/Hell-Influence-Aflatoxins-2000a.pdf Aflatoxin level in 300 farmers' stores in four agro-ecological zones in Benin, a west African coastal country, were determined over a period of 2 years. At sampling a questionnaire was used to evaluate maize storage practices. Farmers were asked what storage structure they used, their storage form, storage period, pest problems in storage and what was done against them. Beninese farmers often changed their storage structures during the storage period, transfering the maize from a drying or temporary store to a more durable one. Most of the farmers complained about insects damaging stored maize, Often, storage or cotton insecticides were utilized against these pests. Regression analysis identified those factors that were associated with increased or reduced aflatoxin. Maize samples in the southern Guinea and Sudan savannas were associated with higher aflatoxin levels and the forest/savanna mosaic was related to lower toxin levels. Factors associated with higher aflatoxin were: storage for 3-5 months, insect damage and use of Khaya senegalensis-bark or other local plants as storage protectants. Depending on the agroecological zone, storage structures that had a higher risk of aflatoxin development were the "Ago", the "Secco", the "Zingo" or storing under or on top of the roof of the house. Lower aflatoxin levels were related to the use of storage or cotton insecticides, mechanical means or smoke to protect against pests or cleaning of stores before loading them with the new harvest. Fewer aflatoxins were found when maize was stored in the "Ago" made from bamboo or when bags were used as secondary storage containers. (C) 2000 Elsevier Science Ltd. All rights reserved.

Hell, K., K. F. Cardwell, et al. (2000). "Influence of insect infestation on aflatoxin contamination of stored maize in four agroecological regions in Benin." African Entomology 8(2): 169-177. ://000167228800002 and http://journals.sabinet.co.za/essa/ http://journals.sabinet.co.za/ej/ejour_ento.html Insect species and damage levels were evaluated and related to aflatoxin content in maize sampled from farmers' stores in four agroecological zones over a two-year period in Benin, West- Africa. In 1993, no aflatoxin was detected in maize that was free of insect damage. In the same year, in maize with more than 70 % of cobs damaged by insects 30.3 % were aflatoxin- positive, with a mean aflatoxin contamination of 77.8 ppb (parts per billion or mug/kg). Grain moisture increased with damage levels. The mean aflatoxin content of maize infested with Carpophilus dimidiatus Fabricius (Coleoptera: Nitidulidae) was significantly higher than maize free of this pest (F = 5.05, P less than or equal to 0.05). In 1994/95, the density of Mussidia nigrivinella Ragonot (Lepidoptera: Pyralidae), was significantly higher in the Northern Guinea Savanna than in the other zones, and the presence of this pest was positively correlated with the cob area visibly infected with Aspergillus flavus Link (Deutoremycetes: Monoliales) (r = 0.239, P less than or equal to 0.05) early in storage. Six months later, damage levels due to insects were significantly lower in the Sudan Savanna than in the other ecozones. The infestation level of the most common storage pest, Sitophilus zeamais Motschulsky (Coleoptera: Curcilionidae) decreased from the south to the north. After six months of storage aflatoxin level was positively correlated with the cob area damaged by Sesamia calamistis Hampson (Lepidoptera: Noctuidae) (r = 0.25, P less than or equal to 0.05), the number of Cryptophlebia leucotreta (Meyrick) (Lepidoptera: Tortricidae) observed on maize (r = 0.26, P less than or equal to 0.05) and cob area damaged by S. zeamais (r = 0.22, P less than or equal to 0.05).

Hellmich, R. L. and G. P. Munkvold (2001). "Reduced mycotoxins in transgenic (Bt) maize." Abstracts of Papers of the American Chemical Society 222: U67-U67. ://000170690000250

Hendrickse, R. G. (1999). "Of sick turkeys, kwashiorkor, malaria, perinatal mortality, heroin addicts and food poisoning: research on the influence of aflatoxins on child health in the tropics." Annals of Tropical Paediatrics 19(3): 229-235. ://000082467100001 NOT IN EZB, NOT IN NEBIS, 42$ Similarities between the geographical and climatic prevalences of kwashiorkor and of exposure to dietary aflatoxins, and between the biochemical, metabolic and immunological derangements in kwashiorkor and those in animals exposed to aflatoxins, prompted investigation of the associations between kwashiorkor and aflatoxins. Studies in Africa in the 1980s indicated a role for these toxins in the pathogenesis of the disease. Paediatric cases of kwashiorkor are less prone to severe Plasmodium falciparum malaria than normal children. In mice infected with P. berghei, aflatoxin exposure inhibits parasite growth and ameliorates morbidity. Aflatoxins occur in less than or equal to 40% of samples of breast-milk from tropical Africa, usually as low concentrations of the relatively non- toxic derivatives of aflatoxin B-1 (AFB(1)) but sometimes as high concentrations of the very toxic AFB(1). This could explain kwashiorkor in breastfed babies. Aflatoxin exposure occurs in greater than or equal to 30% of pregnancies in tropical Africa and the toxins are often in cord blood, sometimes at extremely high concentrations. Aflatoxins are now incriminated in neonatal jaundice and there is circumstantial evidence that they cause perinatal death and reduced birthweight. Aflatoxin-induced immunosuppression may explain the aggressive behaviour of HIV infection in Africa. There are similarities between observations on HIV cases in Africa and those on heroin addicts in Europe, where 'street' heroin is frequently contaminated with aflatoxin. Aflatoxins were found in 20% of random urine samples from heroin addicts in the UK and The Netherlands. Aflatoxins have also been incriminated in episodes of food poisoning which have been associated with serious morbidity and mortality, particularly among young children.

Higa, A., M. Kimura, et al. (2003). "Expression in cereal plants of genes that inactivate fusarium mycotoxins." Bioscience Biotechnology and Biochemistry 67(4): 914-918. ://000182733600039 Trichothecene 3-O-acetyltransferase (encoded by Tri101) inactivates the virulence factor of the cereal pathogen Fusarium graminearum. Zearalenone hydrolase (encoded by zhd101) detoxifies the oestrogenic mycotoxin produced by the same pathogen. These genes were introduced into a model monocotyledon rice plant to evaluate their usefulness for decontamination of mycotoxins. The strong and constitutive rice Act1 promoter did not cause accumulation of TRI101 protein in transgenic rice plants. In contrast, the same promoter was suitable for transgenic production of ZHD101 protein; so far, five promising To plants have been generated. Low transgenic expression of Tri101 was suggested to be increased by addition of an Omega enhancer sequence upstream of the start codon.

Horner, T. A., G. P. Dively, et al. (2003). "Development, survival and fitness performance of Helicoverpa zea (Lepidoptera : Noctuidae) in MON810 Bt field corn." Journal of Economic Entomology 96(3): 914-924. ://000183648000057 AND http://www.botanischergarten.ch/Bt/Horner-Development-Survival-Helicoverpa-2003.pdf Helicoverpa zea (Boddie) development, survival, and feeding injury in MON810 transgenic ears of field corn (Zea mays L.) expressing Bacillus thuringiensis variety kurstaki (Bt) Cry1Ab endotoxins were compared with non-Bt ears at four geographic locations over two growing seasons. Expression of Cry1Ab endotoxin resulted in overall reductions in the percentage of damaged ears by 33% and in the amount of kernels consumed by 60%. Bt-induced effects varied significantly among locations, partly because of the overall level and timing of H. zea infestations, condition of silk tissue at the time of egg hatch, and the possible effects of plant stress. Larvae feeding on Bt ears produced scattered, discontinuous patches of partially consumed kernels, which were arranged more linearly than the compact feeding patterns in non-Bt ears. The feeding patterns suggest that larvae in Bt ears are moving about sampling kernels more frequently than larvae in non-Bt ears. Because not all kernels express the same level of endotoxin, the spatial heterogeneity of toxin distribution within Bt ears may provide an opportunity for development of behavioral responses in H. zea to avoid toxin. MON810 corn suppressed the establishment and development of H. zea to late instars by at least 75%. This level of control is considered a moderate dose, which may increase the risk of resistance development in areas where MON810 corn is widely adopted and H. zea overwinters successfully. Sublethal effects of MON810 corn resulted in prolonged larval and prepupal development, smaller pupae, and reduced fecundity of H. zea. The moderate dose effects and the spatial heterogeneity of toxin distribution among kernels could increase the additive genetic variance for both physiological and behavioral resistance in H. zea populations. Implications of localized population suppression are discussed.

Howard, P. C., L. H. Couch, et al. (2002). "Comparison of the toxicity of several fumonisin derivatives in a 28-day feeding study with female B6C3F(1) mice." Toxicology and Applied Pharmacology 185(3): 153-165. ://000180061900001 Fumonisin mycotoxins are produced by Fusaria fungi that grow worldwide primarily on corn. Fumonisin B-1 the most predominant form in corn samples, is a renal carcinogen in male F344/N rats and a hepatocarcinogen in female B6C3F(1) mice when fed at concentrations higher than 50 ppm (70 mumol/kg) in the diet for 2 years. We sought to determine the relative toxicities of several naturally occurring fumonisin derivatives when included in the diet of female B6C3F(1) mice. Mice were fed diets containing fumonisin B-1 fumonisin B-2, fumonisin B-3, fumonisin P1, hydrolyzed-fumonisin B-1, N-(acetyl)fumonisin B- 1, or N- (carboxymethyl)fumonisin B-1 (approximately 0, 14, 70, and 140 mumol/kg diet) for 28 days. None of the doses used caused a decrease in body weight gain over the 28 days. Serum levels of total bile acids, cholesterol, and alkaline phosphatase were increased only in mice receiving 72 and 143 mumol/kg fumonism B-1, suggesting that only fumonisin B-1 was hepatotoxic in the mice. Corroborating this observation, the liver weight, relative to body weight, was decreased only in the mice that consumed 143 mumol/kg fumonisin B-1. Consistent with fumonisin B-1 inhibition of ceramide synthase, the liver sphinganine-to-sphingosine ratio was increased and the liver ceramide levels were decreased only in the mice receiving 72 and 143 mumol/kg fumonisin B-1. Increased hepatocellular apoptosis, hepatocellular hypertrophy, Kupffer cell hyperplasia, and macrophage pigmentation were detected in the mice consuming 72 and 143 mumol/kg fumonisin B-1. The other fumonisin derivatives did not alter serum analytes, organ weights, or hepatic structure. These results suggest that, of the naturally occurring fumonisins, fumonisin B-1 is the principal hepatotoxic derivative in the B6C3F(1) mouse. (C) 2002 Elsevier Science (USA).

Howard, P. C., R. M. Eppley, et al. (2001). "Fumonisin B-1 carcinogenicity in a two-year feeding study using F344 rats and B6C3F(1) mice." Environmental Health Perspectives 109(2 supplement): 277-282. ://WOS:000168824500014 AND http://www.botanischergarten.ch/Bt/Howard-FumonisinB1-Carcinogenicity-2001.pdf Fumonisin B-1 (FB1) is a mycotoxin isolated from Fusarium fungi that contaminate crops worldwide. A previous study demonstrated that FB1 promoted preneoplastic foci in initiated rats and induced hepatocellular carcinomas in ED IX rats at 50 parts per million (ppm), but fundamental dose-response data were not available to assist in setting regulatory guidelines for this mycotoxin. To provide this information, female and male F344/N/Nctr BR rats and B6C3F(1)/Nctr BR; mice were fed for two years a powdered NIH- 31 diet containing the following concentrations of FB1: female rats, 0, 5, 15, 50, and 100 ppm; male rats, 0, 5, 15, 50, and 150 ppm; female mice, 0, 5, 15, 50, and 80 ppm; male mice, 0, 5, 15, 80, and 150 ppm. FB1 was not tumorigenic in female F344 rats with doses as high as 100 ppm. Including FB, in the diets of male rats induced renal tubule adenomas and carcinomas in 0/48, 0/40, 9/48, and 15/48 rats at 0, 5, 15, 50, and 150 ppm, respectively. Including up to 150 ppm FB1 in the diet of male mice did not affect tumor incidence. Hepatocellular adenomas and carcinomas were induced by FBI in the female mice, occurring in 5/47, 3/48, 1/48, 19/47, and 39/45 female mice that consumed diets containing 0, 5, 15. 50, and 80 ppm FB1, respectively. This study demonstrates that FB1 is a rodent carcinogen that induces renal tubule tumors in male F344 rats and hepatic tumors in female B6C3F(1) mice.

Howard, P. C., A. Warbritton, et al. (2001). "Compensatory regeneration as a mechanism for renal tubule carcinogenesis of fumonisin B-1 in the F344/N/Nctr BR rat." Environmental Health Perspectives 109(2 supplement): 309-314. ://WOS:000168824500018 AND http://www.botanischergarten.ch/Bt/Howard-Compensatory-Fumonisin-2001.pdf Fumonisin B-1 (FB1) is a fungal metabolite of Fusarium verticillioides (= F. moniliforme), a fungus that grows on many crops worldwide. Previous studies demonstrated that male ED IX rats consuming diets containing 50 ppm fumonisin B1 developed hepatocellular carcinomas. In our recent studies, diets containing FB1 at 50 ppm or higher concentrations induced renal tubule carcinomas in male F344/N/Nctr BR rats and hepatocellular carcinomas in female B6C3F(1)/Nctr BR mice. The carcinogenicity of FB1 in rats and mice is not due to DNA damage, as several laboratories have demonstrated that FB1 is not a genotoxin. FB, induces apoptosis in cells in vitro. Including FB1 in the diets of rats results in increased hepatocellular and renal tubule epithelial cell apoptosis. In studies with F344/N/Nctr BR rats consuming diets containing up to 484 ppm FB1 for 28 days, female rats demonstrated more sensitivity than male rats in the induction of hepatocellular apoptosis and mitosis. Conversely, induction of renal tubule apoptosis and regeneration were more pronounced in male than in female rats. Induction of renal tubule apoptosis and hyperplasia correlated with the incidence of renal tubule carcinomas that developed in the 2-year feeding study with FB, in the F344/N/Nctr BR rats. The data are consistent with the hypothesis that the induction Of renal tubule carcinomas in male rats could be partly due to the continuous compensatory regeneration of renal tubule epithelial cells in response to the induction of apoptosis by fumonisin B- 1.

Ibeh, I. N. and D. K. Saxena (1998). "Effect of alpha-tocopherol supplementation on the impact of aflatoxin B-1 on the testes of rats." Experimental and Toxicologic Pathology 50(3): 221-224. ://000074340100007

Ibeh, I. N., N. Uraih, et al. (1994). "Dietary Exposure to Aflatoxin in Human Male-Infertility in Benin-City, Nigeria." International Journal of Fertility and Menopausal Studies 39(4): 208-214. ://A1994PF72600004

Ibeh, I. N., N. Uraih, et al. (1991). "Dietary Exposure to Aflatoxin in Benin-City, Nigeria - a Possible Public-Health Concern." International Journal of Food Microbiology 14(2): 171-174. ://A1991GW18800009 AND http://www.botanischergarten.ch/Bt/Ibeh-Dietary-Exposure-1991.pdf

Izzotti, A., L. Scatolini, et al. (1995). "Enhanced Levels of DNA-Adducts in the Liver of Woodchucks Infected with Hepatitis-Virus." Chemico- Biological Interactions 97(3): 273-285. ://A1995RX55700007 Liver DNA specimens from woodchucks kept in captivity, 10 naturally infected with hepatitis virus (WHV) and five WHV- free, were examined for the presence of carcinogen-DNA adducts by P-32-postlabeling. The number of adducts was significantly higher in WHV carriers than in uninfected animals, and the total amounts of adducts per 10(9) nucleotides were also considerably enhanced by WHV infection, when using both butanol extraction (22.2 +/- 7.1 vs. 12.6 +/- 2.8, means +/- S.D.) and nuclease P-1 enrichment (8.5 +/- 5.9 vs. 2.8 +/- 1.7). Two individual adducts were also significantly higher in WHV carriers. No significant variation occurred as related to age, sex or time length of captivity. These findings are consistent with our previous studies supporting an enhanced metabolism of chemical hepatocarcinogens in both human and woodchuck hepadnavirus infections. Several significant and remarkable correlations were pointed out by relating DNA adduct data to more than 30 virological, histopathological and metabolic parameters which had been previously evaluated in the same animals, For instance, numbers and/or levels of adducts were positively related to the amounts of virus present in hepatocytes, to cell damage (gamma-glutamyltranspeptidase activity), to the severity of the liver histopathological picture, and to monooxygenase activities, while they were inversely related to cellular glutathione concentrations and to detoxification of the direct-acting mutagen 4-nitroquinoline 1- oxide. The major adduct significantly correlated with the metabolic activation of the aromatic amine 2-aminofluorene and of the heterocyclic amines 3- amino-1-methyl-5H- pyrido(4,3)indole (Trp-P-2) and 2-amino-3,4- dimethylimidazo(4,5-f)quinoline (MeIQ), whereas another adduct significantly correlated with the metabolic activation of the mycotoxin aflatoxin B-1. Thus, the enhanced metabolism of chemical hepatocarcinogens and the increased formation of carcinogen-DNA adducts in the liver of WHV carriers appear to represent one of the mechanisms contributing to the association between chronic hepadnavirus infection and development of primary hepatocellular carcinoma.

Janardhana, G. R., K. A. Raveesha, et al. (1999). "Mycotoxin contamination of maize grains grown in Karnataka (India)." Food and Chemical Toxicology 37(8): 863-868. ://000082765800007 One hundred and ninety seven maize samples representing different cultivars, collected from different agroclimatic regions of Karnataka (India) were analysed for moisture content, mould incidence, ergosterol and extent of mycotoxin contamination. Moisture content determination by the hot-air oven method revealed significantly high levels of moisture content (15-18%) in 34 (17%) samples, which exceeded the permissible limit for safe storage. Ergosterol quantification by HPLC revealed the presence of ergosterol in many samples collected from rural areas of Karnataka irrespective of the moisture content. Mould enumeration based on blotter and agar plating methods revealed the association of 24 diverse species of both field and storage moulds belonging to 14 genera. Mycotoxins analyses using monoclonal antibody-based enzyme- linked immunosorbent assay (ELISA) and thin-layer chromatography (TLC) revealed mycotoxin contamination in 69 (34.8%) samples. Maize samples with a high incidence of diverse species of moulds and alarmingly high levels of mycotoxins in many samples indicate the need for proper surveillance and monitoring exclusively for the prevention of moulds and mycotoxins in maize produce in Karnataka before it reaches the consumer. (C) 1999 Elsevier Science Ltd. All rights reserved.

Jardine, D. J. and J. F. Leslie (1999). "Aggressiveness to mature maize plants of Fusarium strains differing in ability to produce fumonisin." Plant Disease 83(7): 690-693. ://000081062900015 Four strains each of Fusarium moniliforme (syn. Fusarium verticillioides) and Fusarium thapsinum were tested for aggressiveness toward two maize inbred lines grown under greenhouse conditions. All strains induced significantly longer stalk lesions than those observed in the controls. Mean lesion length resulting from inoculation with strains of F. moniliforme was longer than the mean lesion length resulting from inoculation with strains of F: thapsinum. Within each species, however, there was a broad range of lesion lengths observed, and all tested strains of both species probably should be regarded as potential pathogens of maize. No isolate x inbred interaction. was detected. Fumonisins may play a role in aggressiveness, but under our conditions, stalk rot and the ability to produce fumonisins in vitro were not correlated.

Javed, T., G. A. Bennett, et al. (1993). "Mortality in Broiler Chicks on Feed Amended with Fusarium- Proliferatum Culture Material or with Purified Fumonisin-B(1) and Moniliformin." Mycopathologia 123(3): 171-184. ://A1993MN85500008 AND http://www.botanischergarten.ch/Bt/Javed-Mortality-Broiler-Fumonisin-1993.pdf Two hundred twenty-eight male chicks (Columbia x New Hampshire) were given feed amended with autoclaved culture material (CM) of Fusarium proliferatum Containing fumonisin B1 (FBI), fumonisin B2 (FB2) and moniliformin in 3 separate feeding trials. Purified FBI and moniliformin were given separately and in combination in a fourth feeding trial. Birds were given amended rations at day 1 (Trial 1 and 4), day 7 (Trial 2), and day 21 (Trial 3) and their respective ration was given for 28 days (Trial I), 21 days (Trial 2), 7 days (Trial 3), and 14 days (Trial 4). FBI concentrations were 546, 193, and 61 ppm; FB2 were 98, 38 and 14 ppm; and moniliformin were 367, 193, and 66 ppm in the first 3 feeding trial regimens. Chicks in Trial 4 were given dietary concentrations of purified FBI at 274 and 125 ppm, and moniliformin at 154 and 27 ppm. FBI and moniliformin, both alone and in combination, produced dose- responsive clinical signs, reduced weight gains and mortality in chicks. Age of birds given amended feeds had little difference in the clinical response; however, those given the rations from days 7 or 21 were slightly less susceptible than those given rations beginning at 1 day of age. Additive effects were noted when the toxins were given in combination. When toxins were given separately, adverse effects took longer to occur. A system to monitor pattern and rate of defecation (RD) was developed for assessing the chicks’ approach to feed, water and heat source as illness progressed. Our results indicate that chicks fed corn heavily infected with F. proliferatum under field conditions could suffer acute death similar to that described for ‘spiking mortality syndrome’ during the first 3 weeks of age.

Jones, C., J. R. Ciacci-Zanella, et al. (2001). "Analysis of fumonisin B-1-induced apoptosis." Environmental Health Perspectives 109(2 supplement): 315-320. ://WOS:000168824500019 AND http://www.botanischergarten.ch/Bt/Jones-Analysis-Fumonisin-2001.pdf Fumonisins are mycotoxins produced by Fusarium moniliforme, a prevalent fungus that infects corn and other cereal grains. Fumonisin B-1 (FB1) is the most common mycotoxin produced by F. moniliforme, suggesting it has toxicologic significance. The structure of FB1 resembles sphingoid bases, and it inhibits ceramide synthase. Because sphingoid bases regulate cell growth, differentiation, transformation, and apoptosis, it is not surprising to find that FBI can alter growth of certain mammalian cells. Previous studies concluded FB1-induced apoptosis, or cell cycle arrest, in African green monkey kidney fibroblasts (CV-1). In this study we have identified genes that inhibit FB1-induced apoptosis in CV-1 cells and two mouse embryo fibroblasts (MEF). A baculovirus gene, inhibitor of apoptosis (CpIAP), protected these cells from apoptosis. CpIAP blocks apoptosis induced by the tumor necrosis factor (TNF) pathway as well as other mechanisms. Further support for the involvement of the TNF signal transduction pathway in FB1-induced apoptosis was the cleavage of caspase 8. Inhibition of caspases by the baculovirus gene p35 also inhibited FB1-induced apoptosis, The tumor suppressor gene p53 was not required for FB1-induced apoptosis because p53(-/-) MEF undergo apoptosis following FB1 treatment. Furthermore, Bcl-2 was not an effective inhibitor of FB1-induced apoptosis in CV-1 cells or p53(+/+) MEF. In summary, these results provide new information to help understand the mechanism by which FB l induces apoptosis.

Josephs, R. D., R. Schuhmacher, et al. (2001). "International interlaboratory study for the determination of the Fusarium mycotoxins zearalenone and deoxynivalenol in agricultural commodities." Food Additives and Contaminants 18(5): 417-430. ://000168710700006 Twenty-eight laboratories from 12 different countries participated in an interlaboratory study for the determination of the Fusarium mycotoxin zearalenone (ZON) in maize and deoxynivalenol (DON) in maize and wheat employing their usual in-house methods. The aim of this study was to obtain information about the state-of-the-art of ZON and DON analysis in cereals and to support a knowledge and experience exchange between the participating laboratories in the Weld of mycotoxin analysis. Eight different sample types were distributed to the participants, 'blank' materials, spiked samples (102 mug/kg ZON in maize and 475 mug/kg DON in wheat) and naturally-cont aminated maize and wheat. For the final separation and quantification either gas chromatography (GC), high performance liquid chromatography (HPLC), thin layer chromatography (TLC) or enzyme linked immunosorbent assays (ELISA) were employed by the participating laboratories. Coefficients of variation (CV) between laboratory mean results (outliers rejected) ranged from 28 to 41% for ZON and from 32 to 38% for DON. The results are close to the between laboratory CV criteria of 40% for DON and ZON at concentration levels of >100 mug/kg established by the CEN in 1999. A good trueness was obtained for the wheat samples spiked at 475 mug/kg DON. However, a significant deviation at p = 0.01 from the respective target value was observed for the maize samples spiked at 102 mug/kg ZON. The high CVs can be traced back to problems occurring by determination of the concentration of the participants' own calibrant solutions. Addition ally, the variability of the results is strongly influenced by the use of different final separation and quantification procedures.

Juanlopez, M., M. Carvajal, et al. (1995). "Supervising Program of Aflatoxins in Mexican Corn." Food Additives and Contaminants 12(3): 297- 312. ://A1995RC65700002

Juglal, S., R. Govinden, et al. (2002). "Spice oils for the control of co-occurring mycotoxin-producing fungi." Journal of Food Protection 65(4): 683-687. ://000175000200017 The effect of nine different oils was evaluated on the growth of Aspergillus parasiticus and Fusarium moniliforme. The experimental design to examine the inhibition of mycotoxins involved the incorporation of each of seven oils into broth and patty cultures. The fungal mycotoxin was identified by high- pressure liquid chromatography. Clove oil (eugenol) was the most inhibitory to the growth of A. parasiticus and F. moniliforme, followed by cinnamon (cinnamic aldehyde), oregano (thymol and carvacol) and mace oils (myristin). Neem and eucalyptus oil (cineole) did not affect fungal growth. The feasibility of implementing the results of this study to control mycotoxin toxicity was examined by costoring whole and ground cloves with mycotoxin-infected grain. Addition of both whole and ground cloves markedly reduced the aflatoxin contamination of the grain. These results clearly suggest that commonly occurring mycotoxigenic fungi can be controlled with clove oil (eugenol), thus spice oil successfully inhibited the growth of A. parasiticus and F. moniliforme, regulated the production of fumonisins, and prevented the formation of aflatoxins. The social implication of this finding is that rural communities can prevent the formation of fungal toxins in contaminated grain by simple measures.

Julian, A. M., P. W. Wareing, et al. (1995). "Fungal Contamination and Selected Mycotoxins in Preharvest and Postharvest Maize in Honduras." Mycopathologia 129(1): 5-16. ://A1995RG69900002

Jurgenson, J. E., K. A. Zeller, et al. (2002). "Expanded genetic map of Gibberella moniliformis (Fusarium verticillioides)." Applied and Environmental Microbiology 68(4): 1972-1979. ://000174842200062 Gibberella moniliformis (Fusarium vertillioides) is primarily a pathogen of maize, but it can also cause disease in other crop species. This pathogenicity, as well as the contamination of food- and feedstuffs with the fumonisin mycotoxins, results in economically significant losses to both farmers and food processors. The dissection of important biological characters in this fungus has been hampered by the lack of a uniformly dense genetic map. The existing restriction fragment length polymorphism-based map contains significant gaps, making it difficult to routinely locate biologically important genes, such as those involved in pathogenicity or mycotoxin production, with precision. We utilized amplified fragment length polymorphisms (AFLPs) to saturate the existing genetic map and added 486 AFLP markers to the similar to150 markers on the existing map. The resulting map has an average marker interval of 3.9 map units and averages similar to21 kb/map unit. The additional markers expanded the map from 1,452 to 2,188 map units distributed across 12 chromosomes. The maximum distance between adjacent markers is 29 map units. We identified AFLP markers less than I map unit from the mating type (MAT) locus and 2.5 map units from the spore killer (SK) locus; eight AFLP markers map within 8.5 units of the FUM1 (fumonisin biosynthetic) locus. The increased saturation of this map will facilitate further development of G. moniliformis as a model system for the genetic and population genetic studies of related, but less genetically tractable, plant pathogenic fungi.

Jurjevic, Z., M. Solfrizzo, et al. (2002). "Occurrence of beauvericin in corn from Croatia." Food Technology and Biotechnology 40(2): 91-94. ://000176168300002 The occurrence of beauvericin has been investigated in corn kernel (Zea mays L.) samples collected in 1996 (105 samples) and 1997 (104 samples) from 14 corn-producing counties of Croatia. Corn sample extracts were cleaned up by silica gel minicolumns and analyzed for beauvericin by high performance liquid chromatography with UV diode array detector. Higher incidence of positive samples was found in the 1996 crop as compared to the 1997 crop. In particular, 18 samples (17.4 %) of the 1996 crop were found contaminated with a mean beauvericin content of 393 ng/g and the highest level at 1864 ng/g. Only 1 out of 104 samples collected in the 1997 crop was contaminated with 696 ng/g of the toxin. Beauvericin co- occurred with fumonisins B-1 and B-2 and with ochratoxin A in 17 and 4 samples, respectively. The results of mycological analysis of corn samples for beauvericin producing Fusaritan species were in agreement with results of chemical analysis. In particular, higher incidence of Fusarium verticillioides (Sacc.) Nirenberg (known as Fusarium moniliforme Sheldon) (3.7 %) and Fusarium subglutinans (Wollenweber & Reinking) Nelson, Toussoun & Marasas (5.3 %) was found in 1996 with respect to 1997 (1.9 % of F. verticillioides and 0.4 % of F. subglutinans). This is the first report on the occurrence of beauvericin in Croatia.

Kale, S. P., D. Bhatnagar, et al. (1994). "Isolation and Characterization of Morphological Variants of Aspergillus-Parasiticus Deficient in Secondary Metabolite Production." Mycological Research 98: 645-652. ://A1994NV48900008 Polyketide-producing Aspergillus parasiticus was developed as a model system to study fungal strain degeneration. One wild type and five spore colour and auxotrophic mutants of A. parasiticus (designated sec+ for secondary metabolism plus) making aflatoxin and/or pigmented pathway intermediates were subjected to a protocol of serial mycelial transfers in a defined medium. Variant forms (designated sec- for secondary metabolism minus) were isolated from the sec+ forms after 5-12 transfers. The sec- forms exhibited altered morphology, reduced sporulation and inability to make detectable levels of polyketide secondary metabolites. The variants were stable and did not revert to the parental characteristics after more than ten transfers. This pleiotrophic class of non- aflatoxigenic variants serves as a model system to study the commonly occurring, but poorly understood, phenomenon of strain degeneration in filamentous fungi.

Kale, S. P., J. W. Cary, et al. (2003). "Genetic analysis of morphological variants of Aspergillus parasiticus deficient in secondary metabolite production." Mycological Research 107: 831-840. ://000185272900011 Aflatoxins (AFs) are secondary metabolites produced mainly by Aspergillus parasiticus and A. flavus. To study AF regulation, previously isolated non-toxigenic A. parasiticus see - (for secondary metabolism minus) variants were genetically analysed. In parasexual crossing, the sec- strains failed to form heterokaryons and diploids with other see - strains. Heterokaryon test results suggested that involvement of cytoplasmic elements in the formation of see - phenotype was unlikely. At the molecular level, the coding sequence of the see - aflR (the only known positive regulator of AF pathway) was identical to that of their toxigenic sec+ (for secondary metabolism plus) parents. However, the see - aflR expression was 5- to 10-fold lower compared to that in the sec+ forms. RT- PCR analysis demonstrated that the AF pathway genes were expressed in the see- forms but in trace amounts and in their unprocessed forms. Combined, these results Suggest that qflR is necessary but not sufficient for AF production and that elements involved in fungal development directly or indirectly influence its proper function.

Kale, S. P., J. W. Cary, et al. (1996). "Characterization of experimentally induced, nonaflatoxigenic variant strains of Aspergillus parasiticus." Applied and Environmental Microbiology 62(9): 3399-3404. ://A1996VF61600052 Six previously isolated, nonaflatoxigenic variants of Aspergillus parasiticus, designated sec mutants, were characterized morphologically by electron microscopy, biochemically by biotransformation studies,vith an aflatoxin precursor, and genetically by Northern (RNA) hybridization analysis of aflatoxin biosynthetic gene transcripts, Scanning electron micrographs clearly demonstrated that compared with the parental sec(+) forms, the variant sec forms had an abundance of vegetative mycelia, orders of magnitude reduced number of conidiophores and conidia, and abnormal metulae, Conidiospores were detected in sec cultures only at higher magnifications (x500), in contrast to the sec(+) (wild type) strain, in which abundant conidiospores (masking the vegetative mycelia) were observed even at lower magnifications (x300), All sec(+) forms, but none of the sec forms, showed bioconversion of sterigmatocystin to aflatoxins, Northern blots probed with pathway genes demonstrated lack of expression of both the aflatoxin biosynthetic pathway structural (nor-1 and omtA) and regulatory (aflR) genes in the sec forms; PCR and Southern hybridization analysis confirmed the presence of the genes in the sec genomes. Thus, the loss of aflatoxigenic capabilities in the sec form is correlated with alterations in the conidial morphology of the fungus, suggesting that the regulation of aflatoxin synthesis and conidiogenesis may be interlinked.

Karlovsky, P. (1999). "Biological detoxification of fungal toxins and its use in plant breeding, feed and food production." Natural Toxins 7(1): 1- 23. ://000083573600001 AND http://www.botanischergarten.ch/Bt/Karlovsky-Biological-Decontamination-1999.pdf Enzymatic inactivation of fungal toxins is an attractive strategy for the decontamination of agricultural commodities and for the protection of crops from phytotoxic effects of fungal metabolites. This review summarizes research on the biological detoxification of fungal toxins by microorganisms and plants and its practical applications. Some mycotoxins are detoxified during ensiling and other fermentation processes (aflatoxins, alternariol, mycophenolic acid, patulin, PR toxin) while others are transformed into toxic products or survive fermentation unchanged. Plants can detoxify fomannoxin, fusaric acid, HC-toxin, ochratoxin A and oxalate but the degradation of deoxynivalenol has yet to be proven. Microflora of the digestive tract of vertebrates and invertebrates exhibit detoxification activities towards aflatoxins, ochratoxin A, oxalate and trichothecenes. Some toxin-producing fungi are able to degrade or transform their own products under suitable conditions. Pure cultures of bacteria and fungi which detoxify mycotoxins have been isolated from complex microbial populations by screening and enrichment culture techniques. Genes responsible for some of the detoxification activities have been cloned and expressed in heterologous hosts. The detoxification of aflatoxins, cercosporin, fumonisins fusaric acid, ochratoxin A, oxalic acid, patulin, trichothecenes and zearalenone by pure cultures is reviewed. Finally, current application of these results in food and feed production and plant breeding is summarized and expected future developments are outlined. Copyright (C) 1999 John Wiley & Sons, Ltd.

Kedera, C. J., J. F. Leslie, et al. (1994). "Genetic Diversity of Fusarium Section Liseola (Gibberella- Fujikuroi) in Individual Maize Stalks." Phytopathology 84(6): 603-607. ://A1994NU25500010 Isolates belonging to Fusarium section Liseola (teleomorph Gibberella fujikuroi), primarily F. moniliforme, F. proliferatum, and F.subglutinans, are recovered from maize worldwide. Consistent isolation of these fungi from symptomatic and asymptomatic plant tissues suggests that the fungus can systemically colonize maize plants; however, the number of strains that colonize a single plant has not been determined. Using vegetative compatibility groups to differentiate among strains, we have shown that most maize plants are infected by two to three strains belonging to Fusarium section Liseola. Some of the strains recovered from the stalk usually are recovered from the ear as well. Multiple strains per plant make it more likely that perithecia formation and sexual recombination in this heterothallic fungus can occur under field conditions, because strains of opposite mating type can be found within the same plant. Such multiple infections also make it difficult to attribute particular disease symptoms to a particular strain. The identification of multiple Fusarium strains within a maize plant illustrates that when studying this host-pathogen relationship, we are examining a population as well as an individual strain-host plant interaction.

Kedera, C. J., R. D. Plattner, et al. (1999). "Incidence of Fusarium spp. and levels of fumonisin B-1 in maize in western Kenya." Applied and Environmental Microbiology 65(1): 41-44. ://000077901800007 and http://www.botanischergarten.ch/Mycotoxins/Kedera-Fumonisin-Kenya-1999.pdf Maize kernel samples were collected in 1996 from smallholder farm storages in the districts of Bomet, Bungoma, Kakamega, Kericho, Kisii, Nandi, Siaya, Trans Nzoia, and Vihiga in the tropical highlands of western Kenya, Two-thirds of the samples were good- quality maize, and one-third were poor-quality maize with a high incidence of visibly diseased kernels. One hundred fifty-three maize samples were assessed for Fusarium infection by culturing kernels on a selective medium. The isolates obtained were identified to the species level based on morphology and on formation of the sexual stage in Gibberella fujikuroi mating population tests. Fusarium moniliforme (G. fujikuroi mating population A) was isolated most frequently, but F. subglutinans (G. fujikuroi mating population E), F. graminearum, F. oxysporum, F, solani, and other Fusarium species were also isolated. The high incidence of kernel infection with the fumonisin-producing species F. moniliforme indicated a potential for fumonisin contamination of Kenyan maize. However, analysis of 197 maize kernel samples by high- performance liquid chromatography found little fumonisin B-1 in most of the samples. Forty-seven percent of the samples contained fumonisin B-1 at levels above the detection limit (100 ng/g), but only 5% were above 1,000 ng/g, a proposed level of concern for human consumption. The four most-contaminated samples,,vith fumonisin B-1 levels ranging from 3,600 to 11,600 ng/g, were from poor-quality maize collected in the Kisii district. Many samples with a high incidence of visibly diseased kernels contained little or no fumonisin B-1, despite the presence off. moniliforme. This result may be attributable to the inability of F. moniliforme isolates present in Kenyan maize to produce fumonisins, to the presence of other ear rot fungi, and/or to environmental conditions unfavorable for fumonisin production.

Keller, N. P., T. E. Cleveland, et al. (1992). "Variable Electrophoretic Karyotypes of Members of Aspergillus Section Flavi." Current Genetics 21(4-5): 371-375. ://A1992HN93400018 Contour-clamped homogeneous electric field gel electrophoresis was used to establish karyotypes for fungi of Aspergillus Section Flavi. Under identical electrophoretic conditions, five to eight chromosomal bands were separated in Aspergillus flavus isolates and five to seven chromosomal bands in A. parasiticus isolates. Each distinct chromosomal band contained one or more chromosomes. Other members of Aspergillus Section Flavi (A. oryzae, A. sojae, and A. tamarii) had similar karyotypes to those of A. flavus and A. parasiticus. A related species, A. versicolor, showed six chromosomal bands. With the exception of small chromosomes present in some isolates, the estimated sizes of chromosomes for all six species range from approximately 3.0 to greater-than-or-equal-to 7.0 Mb. It is likely that all isolates of these species contain the same number of large (> 3 Mb) chromosomes; however, not all of the chromosomal bands could be resolved into separate chromosomes for each isolate due to chromosome length polymorphisms. This variability, observed in A. flavus and A. parasiticus, generated unique chromosomal band patterns within these species. The total genome sizes of these fungi were at least as large as those reported for A. nidulans and A. niger (31- 38.5 Mb). Conserved genes were mapped to analogous chromosomes of A. flavus and A. parasiticus by gene hybridization.

Keller, N. P., H. C. Dischinger, et al. (1991). "Purification of a 2nd Methyltransferase Active in the Aflatoxin Biosynthetic-Pathway." Faseb Journal 5(4): A822-A822. ://A1991FC20702623

Keller, N. P., H. C. Dischinger, et al. (1993). "Purification of a 40-Kilodalton Methyltransferase Active in the Aflatoxin Biosynthetic-Pathway." Applied and Environmental Microbiology 59(2): 479-484. ://A1993KK91600019 The penultimate step in the aflatoxin biosynthetic pathway of the filamentous fungi Aspergillus flavus and A. parasiticus involves conversion of sterigmatocystin to O- methylsterigmatocystin. An S-adenosylmethionine-dependent methyltransferase that catalyzes this reaction was purified to homogeneity (>90%) from 78-h-old mycelia of A. parasiticus SRRC 163. Purification of this soluble enzyme was carried out by five soft-gel chromatographic steps: cell debris remover treatment, QMA ACELL chromatography, hydroxylapatite-Ultrogel chromatography, DEAE-Spherodex chromatography, and Octyl Avidgel chromatography, followed by MA7Q high-performance liquid chromatography. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the protein peak from this step on silver staining identified a single band of approximately 40 kDa. This purified protein was distinct from the dimeric 168- kDa methyltransferase purified from the same fungal strain under identical growth conditions (D. Bhatnagar, A. H. J. Ullah, and T. E. Cleveland, Prep. Biochem. 18:321-349, 1988). The chromatographic behavior and N-terminal sequence of the 40- kDa enzyme were also distinct from those of the 168-kDa methyltransferase. The molar extinction coefficient of the 40- kDa enzyme at 278 nm was estimated to be 4.7 X 10(4) M-1 cm-1 in 50 mM potassium phosphate buffer (pH 7.5).

Keller, N. P., S. Segner, et al. (1995). "Stcs, a Putative P-450 Monooxygenase, Is Required for the Conversion of Versicolorin-a to Sterigmatocystin in Aspergillus-Nidulans." Applied and Environmental Microbiology 61(10): 3628-3632. ://A1995RY07100019 Sterigmatocystin (ST) and aflatoxin are carcinogenic end point metabolites derived from the same biochemical pathway, which is found in several Aspergillus spp. Recently, an ST gene cluster, containing approximately 25 distinct genes that are each proposed to function specifically in ST biosynthesis, has been identified in Aspergillus nidulans. Each of these structural genes is named stc (sterigmatocystin) followed by a consecutive letter of the alphabet. We have previously described stcU (formerly verA) as encoding a keto-reductase required for the conversion of versicolorin A to ST. We now describe a second A. nidulans gene, stcS (formerly verB), that is located within 2 kb of stcU in the ST gene cluster. An stcS-disrupted strain of A. nidulans, TSS17, was unable to produce ST and converted ST/aflatoxin precursors to versicolorin A rather than ST, indicating that stcS functions at the same point in the pathway as stcU, Genomic sequence analysis of stcS shows that it encodes a cytochrome P-450 monooxygenase and constitutes a novel P-450 family, CYP59, Assuming that StcU activity mimics that of similar P-450s, it is likely that StcU catalyzes one of the proposed oxidation steps necessary to convert versicolorin A to ST, These results constitute the first genetic proof that the conversion of versicolorin A to ST requires more than one enzymatic activity.

Kellerman, T. S., W. F. O. Marasas, et al. (1990). "Leukoencephalomalacia in 2 Horses Induced by Oral Dosing of Fumonisin-B1." Onderstepoort Journal of Veterinary Research 57(4): 269-275. ://A1990EV73900010 Leukoencephalomalacia (LEM) was induced by the oral administration of fumonisin B1 (FB1) to 2 horses: a filly received 59,5 mg/kg of a 50 % preparation of FB1, administered in 21 doses of 1,25-4 mg/kg over 33 days; a colt, 44,3 mg/kg of 95 % pure FB1 in 20 doses of 1-4 mg/kg in 29 days. Both animals developed nervous signs such as apathy, changes in temperament, inco-ordination, walking into objects, and one showed paralysis of the lips and tongue. Characteristic lesions of LEM were present in the brains. These trials proved conclusively that FB1 can induce LEM in horses.

Keyser, Z., H. F. Vismer, et al. (1999). "The antifungal effect of fumonisin B-1 on Fusarium and other fungal species." South African Journal of Science 95(10): 455-458. ://000084208800009 Fumonisins are mycotoxins produced by several Fusarium species that are commonly found on maize and maize products. They have diverse toxicological effects in animals and are associated with oesophageal cancer in humans, but their function in nature is obscure. To determine any antifungal effect of fumonisin B-1 (FB1) on Fusarium verticillioides (= F. moniliforme), F. proliferatum, F. globosum, F: subglutinans, ir graminearum, Penicillicum expansum, Aspergillus flavus, Alternaria alternata and Botrytis cinerea, the sensitivity of these fungi was tested by an agar-diffusion method on PDA plates at FB1 concentrations of 40-0.05 mM at pH 5.45. Fumonisin B-1 inhibited mycelial growth of five of the nine fungi tested. The minimum inhibitory concentration of FB1 ranged from 0.25-0.5 mM for A. alternata, 1-5 mM for P. expansum and B. cinerea, and 5-10 mM for F. graminearum, whereas the other fungi tested showed no sensitivity to the mycotoxin. A small inhibition zone was visible with F. proliferatum, a FB1-producing species, at 40 mM. The mycelial growth of the two other FB1-producing species, F. verticillioides and F: globosum, was not affected by the toxin. This is the first report on the antifungal activity of FB1.

Kim, E. K., P. M. Scott, et al. (2003). "Hidden fumonisin in corn flakes." Food Additives and Contaminants 20(2): 161-169. ://WOS:000181145400007 Twenty-five samples of retail corn flakes (from 15 lots) were analysed for fumonisin B-1 (FB1) and fumonisin B-2 (FB2). They were detected in 22 and 12 samples, respectively, at respective mean concentrations 68 and 8 ng g(-1). Samples were extracted with methanol-acetonitrile water (25:25:50) and there was an excellent correlation for FB1 between results obtained with C-18 clean-up and those obtained with the immunoaffinity column (IAC) clean-up. After extraction of the corn flakes residue with 1% sodium dodecyl sulphate (SDS) solution and hydrolysis with 2 N potassium hydroxide, hidden (protein bound) fumonisin was determined as HFB1, which was found in residues from all the corn flakes samples, even those containing no detectable FB1; the average concentration of HFB1 was 101 ng g(-1), equivalent to 180 ng FB1 g(-1). Thus, our results showed an average of 2.6 times more FB1 present in bound form as was determined by conventional analysis. We found a correlation coefficient of 0.5034 for a logarithmic relationship between the FB1 (C-18 clean-up) and HFB1 concentrations The highest concentration of HFB1 formed was 288 ng g(-1) from a sample containing only 12-15 ng FB1 g(-1), while the lowest concentration of HFB1 was 26 ng g(-1) from a sample with 152- 155 ng FB1 g(-1). This low degree of correlation should be taken into account by food safety authorities in estimates of human exposure to protein bound fumonisin.

Kim, E. K., P. M. Scott, et al. (2002). "Extraction of fumonisins B-1, and B-2 from white rice flour and their stability in white rice flour, cornstarch, cornmeal, and glucose." Journal of Agricultural and Food Chemistry 50(12): 3614-3620. ://WOS:000175961100043 To extract fumonisin B-1 (FB1) and fumonisin B-2 (FB2) from Thai white rice flour, different solvent mixtures, temperatures, pH values, and addition of enzymes or ethylenediaminetetraacetic acid disodium salt (Na(2)EDTA) were examined. Three extractions with 0.1 M Na(2)EDTA achieved the highest recoveries. Initial recoveries of fumonisins added to white rice flour, cornstarch, cornmeal, and glucose varied with commodity. Funonisins disappeared in Thai white rice flour after 12 h. but 55% remained in another white rice flour. With cornstarch 20-30% fumonisins remained after 24 h: only 43% of C-14-labeled FB1 materials extracted from cornstarch was eluted with methanol from an immunoaffinity column. Fumonisins were stable in cornmeal for 24 h but only similar to50% remained after 30 days. With glucose, 25% of FB1 and FB2 remained 24 h after addition: N-(1-deoxy-D-fructos-1- yl)FB1 and N-(carboxymethyl)FB1 were detected in lower amounts than residual FB1 after 3 months.

Kim, E. K., D. H. Shon, et al. (2001). "Natural occurrence of aflatoxins in Korean meju." Food Additives and Contaminants 18(2): 151-156. ://000167153600006 Aflatoxin B-1 (AFB(1)) was found in 35 of 60 (58.3%) meju samples with an average concentration of 7.3 ng/g by ELISA. Contamination of AFB(1) was confirmed in 25 of 60 samples (41.6%) using HPLC, with an average concentration of 6.9 ng/g. Mean recoveries from meju ranged from 107% to 170% for AFB(1) using ELISA at a spiking range of 1 to 50 ng/g. Over the same range, recoveries using HPLC were from 70% to 83%. The levels of AFB(1) determined by ELISA and by HPLC demonstrated a close relationship between the two methods (r(2) = 0.9324) employed in this study. In order to evaluate the potential health risks of AFB(1) on Koreans consuming meju, we calculated the estimated probable daily intake (PDI) based on the average contamination levels and compared it with the estimated tolerable daily intake (TDI). The PDIs of AFB(1) from kanjang and dwenjang were determined to be 0.04 and 0.21 ng/kg bw/day, respectively, and were higher than TDIs.

Klich, M. A., J. Yu, et al. (1995). "Hybridization of genes involved in aflatoxin biosynthesis to DNA of aflatoxigenic and non-aflatoxigenic aspergilli." Applied Microbiology and Biotechnology 44(3-4): 439-443. ://A1995TM49800026 Southern blots of DNA from a number of aspergilli belonging to Aspergillus section Flavi, including aflatoxin-producing and non- aflatoxigenic isolates of A. flavus and A. parasiticus, were probed with the aflatoxin pathway genes aflR and omt-1. DNA of all A. flavus, A. parasiticus and A. sojae isolates examined hybridized with both genes. None of the A. oryzae isolates examined hybridized to the aflR probe and one of the three did not hybridize to the omt-1 probe. None of the A. tamarii isolates examined hybridized to either gene. Our results suggest that some isolates in this section do not produce aflatoxin because they lack at least one of the genes necessary for biosynthesis, and that non-producing A. flavus, A. parasiticus and A. sojae strains either lack a gene we did not examine or have genes that are not being expressed.

Kovacs, F. and A. Vanyi (1993). "Circulation of Certain Heavy-Metals, Nitrates and Mycotoxins in the Food-Chain." Magyar Allatorvosok Lapja 48(4): 197-201. ://A1993LC68700001

Kpodo, K., U. Thrane, et al. (2000). "Fusaria and fumonisins in maize from Ghana and their co- occurrence with aflatoxins." International Journal of Food Microbiology 61(2-3): 147-157. ://000165082400004 Fifteen maize samples from four markets and processing sites in Accra, Ghana were analysed for fumonisins B-1, B-2, and B-3. All samples contained fumonisins. Total fumonisin levels for 14 samples ranged from 70 to 4222 mug kg(-1). One sample of visibly mouldy kernels contained 52 670 mug kg(-1) total fumonisins. Mycological examination of the samples showed Aspergillus spp. as the most dominant fungi (76.4%) followed by Penicillium spp. (19.9%). Fusarium formed 2.6% with Fusarium verticillioides as the predominant Fusarium species. Thirty-two Fusarium strains representing five species isolated from the maize samples were tested for the production of fumonisins in maize substrates. From 95% (21 of 22) of the F. verticillioides strains tested, all three types of fumonisins were produced. Total fumonisin levels ranged from 127 to 11 052 mug g(-1). Additional studies on maize samples from 15 processing sites in Accra revealed a co-occurrence of both fumonisins and aflatoxins in 53% (8 of 15) of the samples. (C) 2000 Elsevier Science B.V. All rights reserved.

Kritzinger, Q., T. A. S. Aveling, et al. (2003). "Mycoflora and furnonisin mycotoxins associated with cowpea Vigna unguiculata (L.) walp seeds." Journal of Agricultural and Food Chemistry 51(8): 2188-2192. ://000182037000013 Cowpea seed samples from South Africa and Benin were analyzed for seed mycoflora. Fusarium species detected were F. equiseti, F chlamydosporum, F. graminearum, F. proliferatum, F. sambucinum, F. semitectum, and F. subglutinans. Cowpea seed from South Africa and Benin and F. proliferatum isolates from Benin, inoculated onto maize patty medium, were analyzed for fumonisin production. Samples were extracted with methanol/water and cleaned up on strong anion exchange solid phase extraction cartridges. HPLC with precolumn derivatization using o-phthaldialdehyde was used for the detection and quantification of fumonisins. Cowpea cultivars from South Africa showed the presence of fumonisin B, at concentrations ranging between 0. 12 and 0.61 mug/g, whereas those from Benin showed no fumonisins. This is believed to be the first report of the natural occurrence of FB1 on cowpea seed. Fumonisin B-1, B-2, and B-3 were produced by all F. proliferatum isolates. Total fumonisin concentrations were between 0.8 and 25.30 mug/g, and the highest level of FB1 detected was 16.86 mug/g.

Krska, R. and M. Sulyok (2008). "Martin Weidenbörner: Mycotoxins in foodstuffs." Analytical and Bioanalytical Chemistry 392(3): 323-324. http://dx.doi.org/10.1007/s00216-008-2233-3

Kruger, S. C., B. Kohn, et al. (1999). "Rapid immunoaffinity-based method for determination of zearalenone in corn by fluorometry and liquid chromatography." Journal of Aoac International 82(6): 1364-1368. ://000083858100017 An immunoaffinity-based method was developed to determine zearalenone in corn, Corn samples were extracted in acetonitrile- water (90 + 10, v/v), applied to an immunoaffinity column, and eluted with methanol. The isolated toxin was quantitated either by reaction with aluminum chloride hexahydrate (AlCl3. 6H(2)O) prior to measurement with a fluorometer or injection into a liquid chromatographic (LC) system with a fluorescence detector. Performance was evaluated in terms of antibody specificity, limit of detection, percentage recovery, precision, column capacity, assay linearity, and comparison with AOAC Official Method 985.18. With the immunoaffinity column cleanup procedure, only zearalenone and its metabolites were recognized by the antibody (greater than or equal to 75% recovery). Limits of detection were 0.10 mu g/g for the fluorometer and 0.10 or 0.0025 mu g/g (sensitive method) for the LC method. Percentage recovery averaged 105% (fluorometer) and 93% (LC method), with average relative standard deviations (RSDs) of 15.7 and 9.3%. Naturally contaminated samples gave comparable RSDs of 8.3 and 9.9% for the fluorometer and LC methods, respectively. Column capacity was 4.0 mu g with 89% recovery. Assay linearity was comparable for both methods (r(2) = 0.998). Optimum assay ranges were 0.10-5.0 mu g/g for the fluorometer and 0.10-50 or 0.0025-5.0 mu g/g (sensitive method) for the LC method. Comparative analysis of 17 naturally contaminated corn samples using ZearalaTest LC and the official AOAC LC method for detection of zearalenone showed that ZearalaTest is statistically comparable to the AOAC Official Method 985.18 (r(2) = 0.747).

Kumar, H., Y. K. Jha, et al. (2002). "Detection and estimation of aflatoxin in food grains of Tarai regions and effect of heat treatments on its inactivation." Journal of Food Science and Technology-Mysore 39(5): 479-483. ://000181168600006 A survey on storage conditions and presence of aflatoxin (AF) in groundnut, maize and wheat flour grown in Tarai regions of Nainital was conducted. Among the samples, 41.66% were stored in jute sacks, 30.83% in polythene sacks, 15.00% in wooden boxes and 12.50% in tin boxes and none was stored in airtight containers. Out of 120 samples, 54 (45%) gave bright greenish yellow fluorescence (BGYF) and 36 (30%) were positive to AF contamination. Out of 36 positive samples, 24 (66.7%) were positive for both AFB(1) and G and 12 (33.3%) for AFB(1). Samples contaminated with AF were 20% - wheat flour, 32.5% - maize and 37.5% groundnut. The average concentration of AFB(1) was 30.57 ppb in wheat flour, 80.26 ppb in maize and 97.02 ppb in groundnut. Highest level of AFB(1) (425.30 ppb) was found in groundnut, followed by 283.60 ppb in maize and 85.40 ppb in wheat flour. The number of samples exceeding 20 ppb of AFB(1) were 3 (7.5%) in wheat flour, 9 (22.5%) in maize and 11 (27.5%) in groundnut. Maximum (60.24%) reduction in AFB(1) was obtained in the infected groundnut kernels roasted at 130degreesC for 15 min at 30% moisture and minimum (48%) reduction was at 150degreesC for 10 min at 10% moisture. The samples treated at 15 psi for 90 min at 30% moisture exhibited maximum (62.5%) inactivation whereas minimum (24%) inactivation was found in those treated at 15 psi for 30 min at 10% moisture.

La Penna, M., A. Nesci, et al. (2004). "In vitro studies on the potential for biological control on Aspergillus section Flavi by Kluyveromyces spp." Letters in Applied Microbiology 38(4): 257-264. ://000220098400002 Aims: Antagonist activity of Kluyveromyces spp. isolates on Aspergillus section Flavi was studied. Methods and Results: The screening of isolates were made through studies of growth at different water activities and temperatures, index of dominance (I-D), ecological similarity, antifungal activity and impact on aflatoxin B-1 accumulation. High optical density was obtained at 25 and 30degreesC and 48 h of incubation. Cell growth decreases with decrease in water activity. The predominant interaction was mutual intermingling at a(w) = 0.982 and 0.955, while at a(w) = 0.999 and 0.937 mutual inhibition for contact was exhibited. All isolates were catabolically identical to Aspergillus section Flavi and compete by nutritional source. At high water activities yeasts showed inhibitory activity on Aspergillus strains, inhibition percentages varied between 75 and 100%. The isolates Y-9, Y-14, Y-16, Y-22, Y-25 and Y-33 showed antifungal activity and inhibitory activity on aflatoxin B-1 accumulation at all water activities assayed from all Aspergillus section Flavi strains. Conclusions: The data show that the isolates selected in a wide range of environmental conditions could exert their roll like biological control agents for Aspergillus section Flavi in storage maize ecosystem. Significance Impact of the Study: Isolates of Kluyveromyces spp. may have practical value in the postharvest control of storage maize.

Lamprecht, S. C., W. F. O. Marasas, et al. (1994). "Phytotoxicity of Fumonisins and Ta-Toxin to Corn and Tomato." Phytopathology 84(4): 383- 391. ://A1994NJ17800009 The phytotoxic effects of five fumonisin mycotoxins produced by Fusarium moniliforme, i.e., fumonisin A(1) (FA(1)), A(2) (FA(2)), B-1 (FB1), B-2 (FB2), and B-3 (FB3), together with the aminopolyol hydrolysis products of FB1 and FB2(AP(1) and AP(2), respectively) and tricarballylic acid (TCA) were compared with the host-specific phytotoxin TA-toxin (TA) produced by Alternaria alternata f. sp. lycopersici. A leaf assay was performed on detached leaves of the tomato genotypes Asc/Asc (tolerant to TA) and asc/asc (sensitive to TA) at four concentrations (0.1, 1, 10, and 100 mu M) of each toxin. Seedlings of corn cultivars A1849W and PNR 473 and the two tomato genotypes were also used to assay TA, FB1, FB2, and FB3. The fumonisins caused leaf necrosis identical to that caused by TA and FB1, FB2, FB3, and TA caused significantly (P = 0.01) more necrosis compared with the other metabolites tested. Sterile distilled water (control) and TCA caused no necrosis. Significantly (P = 0.01) more necrosis was observed on the asc/asc genotype compared with the Asc/Asc genotype. There was no significant (P > 0.05) difference between necrosis caused by autoclaved metabolites and that caused by nonautoclaved metabolites. The fumonisins caused dose-dependent reductions in shoot and root length and dry mass of corn and tomato seedlings identical to those caused by TA. The results indicated that TA and FB1 are more phytotoxic to seedlings than are FB2 and FB3. The effects of ah four toxins were more pronounced on seedlings of the sensitive tomato genotype asc/asc than on the tolerant genotype Asc/Asc. No significant differences were recorded in the reaction of the two corn cultivars. The structural similarity of the fumonisin B mycotoxins and TA is therefore reflected by their phytotoxicity to detached tomato leaves as well as to corn and tomato seedlings.

Lau, B. P. Y., P. M. Scott, et al. (2003). "Liquid chromatography-mass spectrometry and liquid chromatography-tandem mass spectrometry of the Altemaria mycotoxins alternariol and alternariol monomethyl, ether in fruit juices and beverages." Journal of Chromatography A 998(1-2): 119-131. ://WOS:000183589100012 Alternariol (AOH) and alternariol monomethyl ether (AME) are among the main mycotoxins formed in apples and other fruits infected by Alternaria alternata. For determination of AOH and AME by LC, apple juice and other fruit beverages were cleaned up on C-18 and aminopropyl solid-phase extraction columns. Positive and negative ion mass spectra of AOH and AME under electrospray (ESI) and atmospheric pressure chemical ionization (APCI) conditions were obtained. Collision-induced dissociation of the [M + H](+) and [M-H](-) ions for both compounds were also studied. The phenolic anions of both compounds are more stable with less fragmentation. In quantitative analysis, negative ion detection also offers lower background and better sensitivity. Sensitive LC-MS and LC-MS-MS confirmatory procedures based on APCI with negative ion detection were applied to confirm the natural occurrence of AOH in nine samples of apple juice and in single samples of some other clear fruit beverages-grape juice, cranberry nectar, raspberry juice, red wine, and prune nectar (which also contained 1.4 ng AME/ml)-at levels of up to 6 ng AOH/ml. Electrospray LC- MS-MS with negative ion detection and in multiple reaction monitoring mode offers higher sensitivity and specificity. Absolute detection was better than 4 pg per injection for both compounds. Crown Copyright (C) 2003 Published by Elsevier Science B.V. All rights reserved.

Lauren, D. R., M. P. Agnew, et al. (1991). "A Survey of the Natural Occurrence of Fusarium Mycotoxins in Cereals Grown in New-Zealand in 1986-1989." Food Additives and Contaminants 8(5): 599-605. ://A1991HD25400005

Lauren, D. R. and M. E. Di Menna (1999). "Fusaria and Fusarium mycotoxins in leaves and ears of maize plants 2. A time course study made in the Waikato region, New Zealand, in 1997." New Zealand Journal of Crop and Horticultural Science 27(3): 215-223. ://000083058300004 The patterns of fungal infection and mycotoxin contamination in leaf and ear sections of plants of two maize (Zea mays L.) hybrids, one resistant to mycotoxin accumulation under New Zealand conditions (Pioneer 3902 (P3902)) and one less so (Pioneer 3751 (P3751)), have been measured. Sampling commenced early in the season, well before ear and tassel formation, and continued until harvest. A number of fungi were isolated, the most common overall being Fusarium. Most common in leaf fractions were Epicoccum, Fusarium, and Alternaria, whereas in ear fractions the most common were Fusarium, Penicillium, Cladosporium, and Mucor. The most common fusaria isolated from leaf fractions were the toxigenic species F. crookwellense and F. graminearum. These species were evident from late February although other, non-toxigenic, species were present in leaf axils from early January. For ear fractions the most common species were F. graminearum, F. crookwellense, and F. subglutinans. Fusarium infection was evident in ears of P3902 from March to April, although heavy infection by the toxigenic species tended to occur later towards May- June, especially for the basal ear fractions. For P3751 ear infection commenced in May, and then was predominantly by toxigenic species. Mycotoxins were found in most plant fractions measured, especially as the plants aged. The toxins found reflected the particular toxigenic Fusarium species present in the fraction. The highest mycotoxin concentration in a leaf fraction was 16.6 mg/ kg of zearalenone (ZEN) in an upper leaf axil sample. Nivalenol (NIV) was also found at up to 7.4 mg/ kg in leaf axils. The most contaminated ear fraction was the rachis, with over 40-95 mg/kg of ZEN, NIV, or deoxynivalenol (DON) at various times. The highest concentration found in kernels was 3.8 mg/kg of DON found in apical kernels of P3751 two weeks before harvest. The results suggest that the mechanisms of maize infection by Fusarium in New Zealand may not be controlled by factors at silk emergence but rather by later season events such as high rainfall and warmer temperatures.

Lauren, D. R., D. J. Jensen, et al. (1996). "Mycotoxins in New Zealand maize: A study of some factors influencing contamination levels in grain." New Zealand Journal of Crop and Horticultural Science 24(1): 13-20. ://A1996UM46900003

Lauren, D. R. and M. A. Ringrose (1997). "Determination of the fate of three Fusarium mycotoxins through wet-milling of maize using an improved HPLC analytical technique." Food Additives and Contaminants 14(5): 435-443. ://A1997XJ75500003

Lawrence, J. F., B. Niedzwiadek, et al. (2000). "Effect of temperature and solvent composition on extraction of fumonisins B-1 and B-2 from corn products." Journal of Aoac International 83(3): 604-611. ://WOS:000087501300010 Fumonisins B-1 and B-2 were extracted from naturally contaminated corn products by using different extraction solvent compositions (methanol-water, acetonitrile-methanol-water, ethanol-water, and 100% water) and a range of temperatures from ambient to 150 degrees C. Ground samples of several corn products and I rice sample were mixed with an adsorbent material (Hydromatrix(TM)), and the fumonisins were extracted in 2 sequential 5 min static extractions at various temperatures. The combined extracts were cleaned up and analyzed by reversed-phase liquid chromatography with fluorescence detection after o- phthaldialdehyde-mercaptoethanol derivatization, The results showed a clear influence of temperature and solvent composition on recovery of fumonisins from some matrixes. With acetonitrile-methanol-water (1 + 1 + 2) the quantity of fumonisins extracted from naturally contaminated taco shells almost tripled in going from 23 degrees to 80 degrees C, and increased by another 30% when ethanol-water (3 + 7) was used as extraction solvent at 80 degrees C. Similar results were obtained with nacho chips. These effects were less pronounced with cornmeal, and small differences due to temperature and solvent composition were observed for corn flakes and rice. The ethanol-water extraction solvent combinations were specifically evaluated in an effort to use the cheapest, least toxic, and most environmentally friendly solvents for organic residue analysis. At 80 degrees C, ethanol-water combinations performed equally or better than methanol-water (8 + 2) or acetonitrile-methanol-water (1 + 1 + 2), combinations which are commonly used for fumonisin extractions. Even 100% water was successful for extracting fumonisins from the products, except for rice. However, increased amounts of water created technical problems and required an increased amount of Hydromatrix in the samples prior to extraction.

Ledoux, D. R., J. N. Broomhead, et al. (2003). "Individual and combined effects of the fusarium Mycotoxins fumonisin B-1 and moniliformin in broiler chicks." Avian Diseases 47(4): 1368-1375. ://000187065200012 The individual and combined effects of feeding fumonisin B-1 (FB1; 0, 100, 200 mg FB1/kg) and moniliformin (M; 0, 100, 200 mg M/kg) were evaluated using a 3 x 3 factorial arrangement of treatments. Significant mortality (P < 0.05) occurred in chicks fed all diets containing 200 mg M/kg (50%-65%). Compared with controls and chicks fed FB1, both feed intake and body weight gain were decreased (P < 0.05) in chicks fed diets containing 100 mg M/kg. Chicks fed M had heavier heart weights (P < 0.05) than control chicks or chicks fed FB1. Compared with controls, chicks fed diets containing 200 mg M/kg or a combination of 200 mg FB1/kg and 100 mg M/kg had increased kidney and liver weights (P < 0.05). Significant FB1 by M interactions (P < 0.05) were observed for serum total protein and aspartate aminotransferase. Mild to moderate periportal extramedullary hematopoiesis and mild focal hepatic necrosis were observed in chicks fed FB1 alone. An increased incidence of large pleomorphic cardiomyocyte nuclei, loss of cardiomyocytes, and mild focal renal tubular mineralization were observed in chicks fed M alone. Both cardiac and renal lesions were observed in chicks fed combinations of FB1 and M. Data indicate FB1 and M, alone or in combination, can adversely affect chick performance and health at these dietary concentrations. The interactive effects of FB1 and M were not synergistic and were less than additive in nature. At the dietary concentrations studied, M is much more toxic to broilers than FB1.

Lee, R. C., J. W. Cary, et al. (1995). "Production and characterization of polyclonal antibodies against norsolorinic acid reductase involved in aflatoxin biosynthesis." Food and Agricultural Immunology 7(1): 21-32. ://A1995TU27900003 Polyclonal antibodies against norsolorinic acid reductase (NSR), an enzyme responsible for the conversion of norsolorinic acid to averantin in the early stage of aflatoxin biosynthesis, were produced after immunizing rabbits with a semi-purified NSR preparation. Immunochemical analysis of the enzyme extracts fr om Aspergillus parasiticus revealed that the antibodies reacted with several protein species, including bands corresponding to NSR activity. The ammonium sulfate-cut IgG was further purified by passing it through a column aimed with protein fractions containing immunoreactivity, but no enzyme activity, isolated from the A. parasiticus extracts that had been subjected to Sepharose gel filtration. After subtractive affinity chromatography, the purified antiserum reacted primarily with two protein bands (of molecular weight 43 and 48 kDa) and was capable of neutralizing the NSR activity. Enzyme-linked immunosorbent assay (ELISA) analysis of various fungal extracts showed that the purified antiserum was highly specific for the enzyme.

Lee, Y. J. and W. M. Hagler (1991). "Aflatoxin and Cyclopiazonic Acid Production by Aspergillus- Flavus Isolated from Contaminated Maize." Journal of Food Science 56(3): 871-873. ://A1991FY15400072

Leitgeb, R., H. Lew, et al. (2000). "Influence of fusarium toxins on growth and carcass characteristics of turkeys." Bodenkultur 51(3): 171-178. ://000165377100005 In a feeding trial with 60 turkeys in 4 feeding groups the effects of mycotoxin contaminated maize on growing performance and carcass traits, chemical composition of eviscerated carcass, organoleptic traits and biochemical parameters of blood were investigated. Four diets with different levels of mycotoxin contamination were tried. In feeding group 1 uncontaminated maize was used, in feeding group 2, 3 and 4; 1/3, 2/3 and 3/3 of uncontaminated maize were substituted by mycotoxin contaminated maize. The percentage of maize in starter feed, grower diet I and II was 36.8, 48.9 and 59.3 %, respectively. The contaminated maize contained 4.94 mg moniliformin, 3.24 mg beauvericin, 2.02 mg deoxynivalenol, and 0.35 mg fumonisines B1 per kg. At the end of the growing period (77 days) live weight of the turkeys of group 1, 2, 3 and 4 was 6.71, 6.26, 6.33 and 6.27 kg and feed conversion rate was 2.07, 2.16, 2.23 and 2.19, respectively. The dressing percentages of eviscerated carcass and roast carcass, the weight of heart, liver Bursa fabricii, spleen and the valuable parts of carcass showed no significant differences between the feeding groups. The DM content of eviscerated carcass was significantly (P=0.10) decreasing from 31.5 to 31.1, 30.9 and 30.1 % for feeding group 1, 2, 3 and 4, respectively. The organoleptic traits (tenderness, juiciness and taste) of breast meat and the biochemical parameters of blood were not at all influenced by the contaminated feed. The experiment shows, that maize contaminated with fusarium toxins had negative effects on growing performance only in the first 8 weeks of age, but not further on.

Leitgeb, R., H. Lew, et al. (1999). "Influence of fusariotoxins on growing and slaughtering perfomance of broilers." Bodenkultur 50(1): 57-66. ://000081595400006 In a feeding trial with 180 broilers the impact of mycotoxin contaminated maize on growing and slaughtering performance, and on physiological parameters was investigated. Four feeding groups with different levels of contamination were used in the experiment. Feeding groups 1, 2, 3 and 4 were fed with 54.6, 36.4, 18.2 and 0 % uncontaminated and 0, 18.2, 36.4 and 54.6 % highly contaminated maize, respectively. Highly contaminated maize contained 9.8 mg Desoxynivalenol, 1.04 mg Moniliformin, 1.43 mg Beauvericin and 0.105 mg Fumonisin B1 per kg. Other components of the diet were 31.4 % soyabean meal, 4.4 % oil, 3 % maize gluten feed, 3 % grass meal, 0.051 % L-lysin-HCl, 0.141 % DL-methionin, 1.22 % limestone, 1.63 % dicalcium-P, 0.15 % salt, 0.16 % NaHCO3, 0.015 % vitamin premix, 0.040 % trace element premix, 0.080 % cholin-Cl and 0.050 % Monensin-Na. At the end of the growing period (37 days) the chickens of feeding group 1, 2, 3 and 4 had a live weight of 1896, 1942, 1904, and 1943 g and the feed conversion rates were 1.81, 1.77, 1.83 and 1.82 kg/kg LW-gain, respectively. The contaminated diets had no negative effect on live weight gain, feed conversion rate and liver weight, but did significantly (P < 0.01) increase heart weight. The chemical composition of carcass and the physiological parameters of the blood (AST, LDH, triglycerid and cholesterin) were not affected. The experiment shows, that maize contaminated with Fusarium toxins had no negative effects on growing and slaughtering performance and on meat quality (tenderness, juiciness and taste), and on blood parameters. As the present investigation shows, the negative effect of Fusarium toxins has been practically overestimated, and Fusarium toxins were probably unjustifiedly blamed for many problems in broiler production.

Lemke, S. L., S. E. Ottinger, et al. (2001). "Development of a multi-tiered approach to the in vitro prescreening of clay-based enterosorbents." Animal Feed Science and Technology 93(1-2): 17-29. ://000171062100002 The successful inclusion of hydrated sodium calcium aluminosilicate clay (HSCAS) in diets for the prevention of aflatoxicosis in animals has led to the investigation of other sorbents that bind mycotoxins. Unfortunately, in vitro studies are not always predictive of in vivo results. In the current study, three previously established in vitro methods: single- concentration sorption. isotherms and chemisorption index (C- alpha) were compared as methods for predicting the adsorption of aflatoxin B-1 (AfB(1)) from solution by four sorbents: HSCAS, charcoal, clinoptilolite and sand. In addition, a gastrointestinal (GI) model was utilized to measure adsorption. Finally, maize was included in modified isotherm studies to examine interactions. As supported by published in vivo studies, HSCAS proved efficacious in all testing methods (>99% bound in single-concentration and GI sorption studies, C-alpha = 0.89, Q(max) = 0.26 mol kg(-1)). Binding of AfB(1) by charcoal was comparable to HSCAS (>99% bound in single- concentration and GI sorption studies, C- alpha = 0.78, Q(max) = 0.889 mol kg(-1)) but was hindered in the presence of maize as seen by the distribution constant (K-d = 1.19 x 10(6) versus 1.11 x 10(5)), Under GI conditions, clinoptilolite demonstrated catalytic activity not observed in the other methods. Results indicate that the GI model is a rapid and more physiologically relevant method of screening sorbents. A three-tiered system that includes: (1) an aqueous binding study; (2) a GI study and (3) isotherms (with and without matrix inclusion), may be used to prescreen mycotoxin/sorbent combinations more effectively before testing in animals. (C) 2001 Elsevier Science B.V. All rights reserved.

Lemmer, E. R., W. C. A. Gelderblom, et al. (1999). "The effects of dietary iron overload on fumonisin B-1-induced cancer promotion in the rat liver." Cancer Letters 146(2): 207-215. ://WOS:000083748500013 AND http://www.botanischergarten.ch/Bt/Lemmer-Effects-Overload-1999.pdf

Lemmer, E. R., W. C. A. Gelderblom, et al. (1998). "The effect of excess hepatic iron on fumonisin B1-induced liver injury and carcinogenesis in the rat." Hepatology 28(4): 1767. ://000076258101765

Lemmer, E. R., P. D. Hall, et al. (1998). "Poor reporting of oocyte apoptosis." Nature Medicine 4(4): 373-373. ://000072906800006

Lemmer, E. R., P. D. Hall, et al. (1999). "Histopathology and gene expression changes in rat liver during feeding of fumonisin B-1, a carcinogenic mycotoxin produced by Fusarium moniliforme." Carcinogenesis 20(5): 817-824. ://000080022700011 AND http://www.botanischergarten.ch/Bt/Lemmer-Histopathology-Fumonisin-1999.pdf Fumonisin B-1 (FB1) is a carcinogenic mycotoxin produced by the fungus Fusarium moniliforme in corn. Feeding of FB1 to rats causes acute liver injury, chronic liver injury progressing to cirrhosis, and sometimes terminates in hepatocellular carcinoma or cholangiocarcinoma. This study describes the histolopathology and changes in gene expression in the rat liver during short-term feeding of FB1. Male Fischer rats were fed either FB1 250 mg/kg or control diet, and were killed weekly for 5 weeks. FB1 caused a predominantly zone 3 'toxic' liver injury, with hepatocyte death due to necrosis and apoptosis, Hepatocyte injury and death were mirrored by hepatic stellate cell proliferation and marked fibrosis, with progressive disturbance of architecture and formation of regenerative nodules, Despite ongoing hepatocyte mitotic activity, oval cell proliferation was noted from week 2, glutathione S- transferase pi-positive hepatic foci and nodules developed and, at later time points, oval cells were noted inside some of the 'atypical' nodules, Northern blot (mRNA) analysis of liver specimens from weeks 3 to 5 showed a progressive increase in gene expression for alpha-fetoprotein, hepatocyte growth factor, transforming growth factor alpha (TGF-alpha) and especially TGF-beta 1 and c-myc, Immunostaining with LC(1-30) antibody demonstrated a progressive increase in expression of mature TGF-beta 1 protein by hepatocytes over the 5 week feeding period. The overexpression of TGF-beta 1 may be causally related to the prominent apoptosis and fibrosis seen with FB1-induced liver injury. Increased expression of c-myc may be involved in the cancer promoting effects of FB1.

Lemmer, E. R., E. G. Shephard, et al. (1996). "An immunohistochemical study of the hepatic response to fumonisin in the rat." Hepatology 24(4): 1643-1643. ://A1996VL28501638

Lemmer, E. R., E. G. Shephard, et al. (1997). "The pathology of fumonisin-induced liver injury in the rat." Hepatology 26(4): 1327-1327. ://A1997XY87401326

Lemmer, E. R., C. J. Vessey, et al. (2004). "Fumonisin B-1-induced hepatocellular and cholangiocellular tumors in male Fischer 344 rats: potentiating effects of 2- acetylaminofluorene on oval cell proliferation and neoplastic development in a discontinued feeding study." Carcinogenesis 25(7): 1257-1264. ://000222124500022 Fumonisin B-1 (FB1) is a naturally occurring mycotoxin produced by Fusarium verticillioides. Dietary exposure to FB1 has been linked to human cancer in certain parts of the world, and treatment with FB1 causes oval cell proliferation and liver tumors in rats. To study the potential role of oval (liver progenitor) cells in the cellular pathogenesis of FB1-induced liver tumors, we gave male F344 rats prolonged treatment with FB1 for 25 weeks, followed by return to control diet until 50 weeks ('stop study'). The time course of FB1- induced liver lesions was followed by examination of serial liver biopsies at set time intervals and post-mortem liver tissue at the end of the study. The effects of different FB1 treatment regimens (5 versus 25 weeks), as well as the modulating effect of 2- acetylaminofluorene (2-AAF), on the kinetics of oval cell proliferation and development of liver tumors were compared. Prolonged treatment with FB1 in normal diet caused persistent oval cell proliferation and generation of both hepatic adenomas and cholangiofibromas (CFs). These liver lesions occurred in the setting of chronic toxic hepatitis and liver fibrosis/cirrhosis, similar to that seen in human hepatocarcinogenesis. Some adenomas and CFs were dysplastic, and one post-mortem liver contained a hepatocellular carcinoma. OV-6(+) oval cells were noted in close relation to proliferative neoplastic liver lesions, and some of these lesions expressed OV-6, suggesting that all these cell types were derived from a common progenitor cell. 2-AAF enhanced the size of FB1-induced glutathione S-transferase pi(+) hepatocellular lesions and the incidence of CFs in post-mortem liver specimens, but this was not statistically significant. In conclusion, this study supports the involvement of dietary FB1 in liver carcinogenesis in male F344 rats. Oval cells may be the source of both the hepatocellular and cholangiocellular tumors induced by prolonged treatment with FB1. 2-AAF appears to have an enhancing effect on FB1-induced liver tumors, presumably due to its potent inhibitory effects on hepatocyte regeneration.

Leontopoulos, D., A. Siafaka, et al. (2003). "Black olives as substrate for Aspergillus parasiticus growth and aflatoxin B-1 production." Food Microbiology 20(1): 119-126. ://000180519700016 Aflatoxin B1 (AFB(1)) is a highly toxic and carcinogenic metabolite produced by certain Aspergillus species on agricultural commodities. Molds isolated from black olives are potentially toxigenic and present a potential health hazard. Olive oil originating from contaminated olives with AFB(1) might also be contaminated. The aim of this study was to investigate A. parasiticus growth and AFB(1) production in black damaged olives inoculated with 100 conidia flask(-1) (1) treated with NaOCl 1.25%, (2) autoclaved at 110degreesC for 2 min, in comparison to the mold growth and AFB(1) production into the yeast extract sucrose (YES) medium under the same conditions of incubation and inoculation. AFB(1) extracted from cultures or olives and purified with immunoaffinity columns, was derivatized to its hemiacetal AFB(2a) and then quantitated by HPLC using fluorescence detector. The recoveries and detection limits from YES and olives were 99.2%, 0.02ng AFB(1)ml(-1) and 94%, 0.15 ng AFB(1)g(-1), respectively. Results showed that mycelia growth was not observed in olives during the 15 days of observation. The maximum growth of A. parasiticus on YES medium was shown on the sixth day. The AFB(1) production for both treated with NaOCl and autoclaved olives inoculated or not with A. parasiticus was not significantly different. On the other hand, AFB(1) levels produced in olives treated with NaOCl were significantly higher as compared with the autoclaved. The range of contamination of all olive samples inoculated or not for the whole period of observation was 0.15-2.3 ng AFB(1)g(-1). The production of AFB(1) in YES medium on the third, the ninth and the 15th day was similar to1000-, similar to2500- and 10000-fold higher, respectively, compared with the production in olives thus showing that black damaged olives of Greek origin are not a substrate favorable for AFB(1) biosynthesis at hazardous levels. Nevertheless, the production is possible at detectable amounts even after a little contamination that could happen randomly. (C) 2002 Elsevier Science Ltd. All rights reserved.

Lepom, P., O. Knabe, et al. (1990). "Occurrence of Fusarium Species and Their Mycotoxins in Maize - Formation of Deoxynivalenol (Don) in a Maize Plot Artificially Inoculated with Fusarium-Culmorum and the Influence of Ensilaging on the Stability of Don Formed." Archiv Fur Tierernahrung-Archives of Animal Nutrition 40(10): 1005-1012. ://A1990ET30000012

Leslie, J. F., W. F. O. Marasas, et al. (1996). "Duckling toxicity and the production of fumonisin and moniliformin by isolates in the A and F mating populations of Gibberella fujikuroi (Fusarium moniliforme)." Applied and Environmental Microbiology 62(4): 1182-1187. ://A1996UD95000009 Two biological species of Gibberella fujikuroi (A and F mating populations) share the Fusarium moniliforme anamorph. Twenty strains of each of these biological species were tested for the ability to produce fumonisins B-1, B-2, and B-3 and moniliformin and for toxicity to 1-day-old ducklings. Most of the members of the A mating population (19 of 20 strains) produced more than 60 mu g of total fumonisins per g, whereas only 3 of 20 members of the F mating population produced more than trace levels of these toxins and none produced more than 40 mu g of total fumonisins per g. In addition, only 3 of 20 members of the A mating population produced more than 1 mu g of moniliformin per g (and none produced more than 175 mu g/g), while all 20 strains of the F mating population produced more than 85 mu g of this toxin per g and 1 strain produced 10,345 mu g/g. The duckling toxicity profiles of the strains of the two mating populations were similar, however, and the level of either toxin by itself was not strongly correlated with duckling toxicity. On the basis of our data we think that it is likely that the members of both of these mating populations produce additional toxins that have yet to be chemically identified. These toxins may act singly or synergistically with other compounds to induce the observed duckling toxicity.

Leslie, J. F., R. D. Plattner, et al. (1992). "Fumonisin B1 Production by Strains from Different Mating Populations of Gibberella-Fujikuroi (Fusarium Section Liseola)." Phytopathology 82(3): 341-345. ://A1992HG36100018

Lew, H., A. Adler, et al. (2001). "Fusarium species and their toxins in Austrian maize." Bodenkultur 52(3): 199-207. ://000173076800001 Since in the middle term the EU is likely to set maximum admissible values for fumonisins as well as other Fusarium toxins one urgent task was to obtain a representative picture of Fusarium infestation and the toxin content of domestic maize. Consequently, the project set out to investigate maize grain samples from the major maize growing areas of Austria. The project, which spanned three vegetation periods and focussed on Fusarium infection, distribution of species and toxin contamination, involved the toxins deoxynivalenol (DON, vomitoxin), 15-acetyldeoxynivalenol, 3-acetyldeoxynivalenol, zeardenone, nivalenol, T-2 toxin, HT-2 toxin, fumonisin B-1, B- 2 and moniliformin. The relatively humid vegetation periods of 1998 and particularly 1996 were dominated by F. graminearum, so that in both years relatively high concentrations of deoxynivalenol and zearalenone could be detected in the maize grain samples. Thus, 41 out of 46 samples from the 96 harvest showed a DON content of over 0.1 mg/kg, with an average content in the positive samples of 0.645 mg/kg. The tests also showed that 15-acetyldeoxynivalenol is far more common in Austrian maize than 3-acetyldeoxynivalenol. The occurrence of the chief moniliformin producer F. subglutinans remained largely uninfluenced by any climatic variations. In all vegetation periods the proportion of this fungus in the total figure of isolated fusaria was around 30%. The percentage of F. avenaceum, also a moniliformin forming species, varied between 14% in 1996, an extremely wet year, and 23% in 1997. In all three vegetation periods about 15% of the maize samples considered showed a moniliformin content of well over 0.05 mg/kg, with an average value of the positive samples of 0.22 mg/kg. In contrast to F. graminearum, F. poae appeared to find favourable conditions especially in 1997, a fairly dry vegetation period. However, infestation of the ears was much less conspicuous; in fact the nivalenol content in all tested maize samples was below the detection limit of 0.05 mg/kg. Finally, the occurrence of the trichothecenes T-2 toxin and HT- 2 toxin in the three years under study was limited to a few isolated cases, with consistently low concentrations. Compared to a similar investigation in the years 1988/89, a significant increase in the incidence of F. proliferatum, a fumonisin- producer, could be observed. Especially in the unusually warm vegetation period of 1998 conditions for the development of F. proliferatum were very good, so that some of the maize samples yielded toxicologically relevant fumonisin contents (up to 2 mg/kg).

Liu, B. H., D. Bhatnagar, et al. (1999). "Purification and characterization of 40-KDa sterigmatocystin O- methyltransferase involved in aflatoxin biosynthesis." Natural Toxins 7(2): 63-69. ://000083573800004 Sterigmatocystin-O-methyltransferase (ST-OMTase), an enzyme catalyzing O-methylation of sterigmatocystin with S- adenosylmethionine (SAM), was purified to electrophoretic homogeneity by immunoaffinity chromatography. A novel spectrofluorometric method was established to quantitatively determine the enzymatic activity of ST-OMTase. The purified protein, with a molecular weight of 40 kDa by SDS-PACE, was sensitive to thiol reagents and low concentrations of heavy metal ions. Using a nutritional shift assay, the expression patterns for ST-OMTase and the transcripts of its corresponding gene, omtA, correlated well with that for aflatoxin B-1 formation. Neither methyltransferase activity nor omtA, mRNA was detected in the fungal cultures of nonaflatoxigenic isolates, including A. flavus, A. sojae, A. nidulans and A. versicolor under optimal growing conditions for aflatoxin B1 production. Copyright (C) 1999 John Wiley & Sons, Ltd.

Liu, B. H., J. F. Brewer, et al. (1997). "Immunochemical identification of AFLR, a regulatory protein, involved in aflatoxin biosynthesis." Food and Agricultural Immunology 9(4): 289-298. ://000072566200006 Polyclonal antibodies against AFLR, the aflR gene product of Aspergillus flavus and A. parasiticus, were generated by immunizing a rabbit with the Escherichia coli-expressed recombinant AFLR protein of A. flavus. Immunoblot analysis revealed that the antibodies not only reacted with the recombinant AFLR protein of A. flavus or A. parasiticus but also with native 47-kDa AFLR in A. flavus and A. parasiticus. Immunoblot analysis revealed that accumulation of the 47-kDa AFLR in cultures of A. flavus and A. parasiticus correlated well with the production of aflatoxin under various culture conditions that regulate aflatoxin formation. Neither AFLR nor aflatoxin was found when A. parasiticus NRRL 2999 was grown in peptone mineral salts (PMS) medium; however, both were detected after the culture was transferred to glucose mineral salts (GMS) medium. The AFLR protein was absent in the non- aflatoxigenic Penicillium and Fusarium species grown in GMS medium. The data indicate that the antibodies obtained in the present studies are specific for AFLR and could be used in various studies to monitor the role of AFLR in regulating aflatoxin biosynthesis.

Liu, Z. M., L. Q. Li, et al. (2008). "Hepatitis B virus infection contributes to oxidative stress in a population exposed to aflatoxin B1 and high-risk for hepatocellular carcinoma." Cancer Letters 263(2): 212-222. ://WOS:000255810500008 AND http://www.botanischergarten.ch/Bt/Liu-Hepatitis-B-Contributes-2008.pdf Biomarkers of hepatitis B virus (HBV) infection, aflatoxin B1 (AFB1) exposure and oxidative stress were detected in 71 hepatocellular carcinoma (HCC) patients and 694 controls from southern China. Plasma level of AFB1-albumin-adducts (AAA) and protein carbonyl content (PCC) were significantly higher in the 71 HCC cases than in any age/gender matched HBV sero-status groups (p < 0.001). HCC patients positive for the p53-249 G-T mutation had a marginally higher level of PCC than those negative for the mutation (p = 0.077). HBV infection had a prominent influence on the association between AFB1 exposure and oxidative stress biomarkers in the controls. Our study indicates a significant contribution from HBV infection to oxidative stress in a population with AFB1 exposure which might substantially increase risk for HCC in this region. (C) 2008 Elsevier Ireland Ltd. All rights reserved.

Logrieco, A., A. Bottalico, et al. (2003). "Epidemiology of toxigenic fungi and their associated mycotoxins for some Mediterranean crops." European Journal of Plant Pathology 109(7): 645-667. ://000185661500002 Recent data on the epidemiology of the common mycotoxigenic species of Fusarium, Alternaria, Aspergillus and Penicillium in infected or colonized plants, and in stored or processed plant products from the Mediterranean area are reviewed. Emphasis is placed on the toxigenicity of the causal fungal species and the natural occurrence of well known mycotoxins (aflatoxins, ochratoxins, fumonisins, trichothecenes, zearalenone, patulin, Alternaria-toxins and moniliformin), as well as some more recently described compounds (fusaproliferin, beauvericin) whose toxigenic potential is not yet well understood. Several Fusarium species reported from throughout the Mediterranean area are responsible of the formation of mycotoxins in infected plants and in plant products, including: Fusarium graminearum, F. culmorum, F. cerealis, F. avenaceum, F. sporotrichioides and F. poae, which produce deoxynivalenol, nivalenol, fusarenone, zearalenone, moniliformin, and T-2 toxin derivatives in wheat and other small grains affected by head blight or scab, and in maize affected by red ear rot. Moreover, strains of F. verticillioides, F. proliferatum, and F. subglutinans, that form fumonisins, beauvericin, fusaproliferin, and moniliformin, are commonly associated with maize affected by ear rot. Fumonisins, were also associated with Fusarium crown and root rot of asparagus and Fusarium endosepsis of figs, caused primarily by F. proliferatum. Toxigenic A. alternata strains and associated tenuazonic acid and alternariols were commonly found in black mould of tomato, black rot of olive and citrus, black point of small cereals, and black mould of several vegetables. Toxigenic strains of A. carbonarius and ochratoxin A were often found associated with black rot of grapes, whereas toxigenic strains of A. flavus and/or P. verrucosum, forming aflatoxins and ochratoxin A, respectively, were found in moulded plant products from small cereals, peanuts, figs, pea, oilseed rape, sunflower seeds, sesame seeds, pistachios, and almonds. Finally, toxigenic strains of P. expansum and patulin were frequently found in apple, pear and other fresh fruits affected by blue mould rot, as well as in derived juices and jams.

Logrieco, A., A. Bottalico, et al. (2004). "Epidemiology of Toxigenic Fungi and their Associated Mycotoxins for Some Mediterranean Crops." European Journal of Plant Pathology 109(7): 645-667. http://dx.doi.org/10.1023/A:1026033021542 AND http://www.botanischergarten.ch/Bt/Pettitt-Association-Fusarium-2004.pdf Recent data on the epidemiology of the common mycotoxigenic species of Fusarium, Alternaria, Aspergillus and Penicillium in infected or colonized plants, and in stored or processed plant products from the Mediterranean area are reviewed. Emphasis is placed on the toxigenicity of the causal fungal species and the natural occurrence of well known mycotoxins (aflatoxins, ochratoxins, fumonisins, trichothecenes, zearalenone, patulin, Alternaria-toxins and moniliformin), as well as some more recently described compounds (fusaproliferin, beauvericin) whose toxigenic potential is not yet well understood. Several Fusarium species reported from throughout the Mediterranean area are responsible of the formation of mycotoxins in infected plants and in plant products, including: Fusarium graminearum, F. culmorum, F. cerealis, F. avenaceum, F. sporotrichioides and F. poae, which produce deoxynivalenol, nivalenol, fusarenone, zearalenone, moniliformin, and T-2 toxin derivatives in wheat and other small grains affected by head blight or scab, and in maize affected by red ear rot. Moreover, strains of F. verticillioides, F. proliferatum, and F. subglutinans, that form fumonisins, beauvericin, fusaproliferin, and moniliformin, are commonly associated with maize affected by ear rot. Fumonisins, were also associated with Fusarium crown and root rot of asparagus and Fusarium endosepsis of figs, caused primarily by F. proliferatum. Toxigenic A. alternata strains and associated tenuazonic acid and alternariols were commonly found in black mould of tomato, black rot of olive and citrus, black point of small cereals, and black mould of several vegetables. Toxigenic strains of A. carbonarius and ochratoxin A were often found associated with black rot of grapes, whereas toxigenic strains of A. flavus and/or P. verrucosum, forming aflatoxins and ochratoxin A, respectively, were found in moulded plant products from small cereals, peanuts, figs, pea, oilseed rape, sunflower seeds, sesame seeds, pistachios, and almonds. Finally, toxigenic strains of P. expansum and patulin were frequently found in apple, pear and other fresh fruits affected by blue mould rot, as well as in derived juices and jams.

Logrieco, A., A. Moretti, et al. (1995). "Occurrence and Toxigenicity of Fusarium-Proliferatum from Preharvest Maize Ear Rot, and Associated Mycotoxins, in Italy." Plant Disease 79(7): 727-731. ://A1995RH93500015

Logrieco, A., G. Mule, et al. (2002). "Toxigenic Fusarium species and mycotoxins associated with maize ear rot in Europe." European Journal of Plant Pathology 108(7): 597-609. ://000178595700001 Several Fusarium species occurring worldwide on maize as causal agents of ear rot, are capable of producing mycotoxins in infected kernels, some of which have a notable impact on human and animal health. The main groups of Fusarium toxins commonly found are: trichothecenes, zearalenones, fumonisins, and moniliformin. In addition, beauvericin and fusaproliferin have been found in Fusarium-infected maize ears. Zearalenone and deoxynivalenol are commonly found in maize red ear rot, which is essentially caused by species of the Discolour section, particularly F. graminearum. Moreover, nivalenol and fusarenone-X were often found associated with the occasional occurrence of F. cerealis, and diacetoxyscirpenol and T-2 toxin with the occurrence of F. poae and F. sporotrichioides, respectively. In addition, the occurrence of F. avenaceum and F. subglutinans usually led to the accumulation of moniliformin. In maize pink ear rot, which is mainly caused by F. verticillioides, there is increasing evidence of the wide occurrence of fumonisin B-1. This carcinogenic toxin is usually found in association with moniliformin, beauvericin, and fusaproliferin, both in central Europe due to the co-occurrence of F. subglutinans, and in southern Europe where the spread of F. verticillioides is reinforced by the widespread presence of F. proliferatum capable of producing fumonisin B-1, moniliformin, beauvericin, and fusaproliferin.

Lombaert, G. A., P. Pellaers, et al. (2003). "Mycotoxins in infant cereal foods from the Canadian retail market." Food Additives and Contaminants 20(5): 494-504. ://WOS:000183421500010 Three hundred and sixty-three samples of cereal-based infant foods were collected from the Canadian retail markelplace over 3 years. The samples included oat-, barley-, soy-, and rice-based infant cereals, mixed-grain infant cereals, teething biscuits, creamed corn, and soy- based formulas. Samples were analysed for targeted mycotoxins (deoxynivalenol, nivalenol, HT-2 toxin, zearalenone, ochratoxin A, fumonisins B-1 and B-2, and five ergot alkaloids). Soy-based cereals (which usually contain corn) exhibited the highest incidences of deoxynivalenol (100%), zearalenone (46%) and fumonisins (75%). Overall, deoxynivalenol was the most frequently detected mycotoxin - it was detected in 63% of samples analysed. Survey results demonstrated the regular occurrence of multiple mycotoxins in cereal-based infant,foods.

Lu, Y., L. Clifford, et al. (2002). "Characterization of fumonisin B-1-glucose reaction kinetics and products." Journal of Agricultural and Food Chemistry 50(16): 4726-4733. ://000177109400050 The reaction of fumonisin B-1 with the reducing sugar D-glucose can block the primary amine group of fumonisin B-1 and may detoxify this mycotoxin. A method to separate hundred milligram quantities of fumonisin B-1-glucose reaction products from the excess D-glucose with a reversed-phase C-18 cartridge was developed. Mass spectrometry revealed that there were four primary products in this chain reaction when fumonisin B-1 was heated with D-glucose at 65 degreesC for 48 h: N-methyl- fumonisin B-1, N- carboxymethyl-fumonisin B-1, N-(3- hydroxyacetonyl)-fumonisin B-1, and N-(2-hydroxy, 2- carboxyethyl)-fumonisin B-1. The N-(1- deoxy-D-fructos-1-yl) fumonisin B-1 (fumonisin B-1-glucose Schiff's base) was detected by mass spectrometry, when fumonisin B-1 was heated with D-glucose at 60 degreesC. The nonenzymatic browning reaction of fumonisin B-1 with excess D-glucose followed apparent first-order kinetics. The activation energy, E-a, was 105.7 kJ/mol. Fumonisin B-1 in contaminated corn could precipitate the nonenzymatic browning reaction with 0.1 M D- glucose at 60 and 80 degreesC.

Lu, Z., W. R. Dantzer, et al. (1997). "Reaction with fructose detoxifies fumonisin B-1 while stimulating liver-associated natural killer cell activity in rats." Journal of Agricultural and Food Chemistry 45(3): 803-809. ://A1997WP00200046

Lubulwa, A. and J. Davis (1994). Estimating the social costs of the impacts of fungi and aflatoxins in maize and peanuts. Proceedings f the Sixth Intlernational Working Conference Stored-product rotect, Wallingford, UK., CAB International.

Lubulwa and Davis (1995) estimated the social costs of the impacts of aflatoxins in corn and peanuts in Indonesia, Philippines and Thailand using economic models that calculate the cost of disability due to aflatoxin-related primary liver cancer in humans and suppression of growth of poultry and pigs. The total annual social cost in these three countries due to aflatoxin in maize was Australian $319 million (Table 12). The estimate for aflatoxin in peanuts was Australian $158 million. Unfortunately, there has been no attempt to make such estimates in Africa.

Mably, M., M. Mankotia, et al. (2005). "Survey of aflatoxins in beer sold in Canada." Food Additives and Contaminants 22(12): 1252-1257. ://WOS:000233957400011 Between March 1998 and March 2002, 304 samples of domestic ( Canadian) and imported beers from 36 countries were picked up for the determination of aflatoxins B-1, B-2, G(1) and G(2). Twelve samples were positive with aflatoxins greater than the limit of quantitation (LOQ) (aflatoxin B-1, 4.4 ng l(-1); aflatoxin B-2, 3.4 ng l(-1); aflatoxin G(1), 11.2 ng l(-1); and aflatoxin G(2), 6.2 ng l(-1)). Five samples from Mexico, two samples from Spain and one from Portugal contained aflatoxin B-1. Four samples from India contained aflatoxins B-1 and B-2. The remaining samples contained less than the LOQ for aflatoxins B-1, B-2, G(1) and G(2). The analytical method for this survey was based on that of Scott and Lawrence ( Scott PM, Lawrence GA. 1997. Determination of aflatoxins in beer. Journal of AOAC International 80: 1229-1234.). Aflatoxins B-1, B-2, G(1) and G(2) were determined at parts per trillion (ng l(-1)) levels in beer by immunoaffinity column cleanup followed by derivatization with trifluoroacetic acid and reversed- phase liquid chromatography with fluorescence detection.

Machinski, M., L. M. V. Soares, et al. (2001). "Aflatoxins, ochratoxin A and zearalenone in Brazilian corn cultivars." Journal of the Science of Food and Agriculture 81(10): 1001-1007. ://000170055000004 Past surveys indicated that the occurrence of aflatoxins, zearalenone and ochratoxin A was not a problem in corn and corn products in the state of Sao Paulo, Brazil. However, according to recent studies, a change in pattern has been detected. To obtain a better overview, these toxins were searched for in 110 samples of freshly harvested corn, corresponding to 48 commercial cultivars planted at three different locations in the state. Aflatoxin contamination was found in 60 (54.5%) of the samples, in levels ranging from 6 to 1600 mu gkg(-1) aflatoxin B-1;. Insect control was exercised, so this was not the main route of corn infection. Endosperm type, germplasm type, number of days to flowering, and length of time the mature corn remained in the field had no effect on aflatoxin contamination. Ochratoxin A was found in two samples (206 and 128 mu gkg(-1)) and zearalenone in one sample (4640 mu gkg(- 1)). Possible causes of the increase in aflatoxin levels may lie in the changing nature of the commercial cultivars employed, associated with the forsaking of the original landraces, and in a change in the toxigenicity pattern of the corn mycoflora Aspergillus flavus/Aspergillus parasiticus prevailing strains. (C) 2001 Society of Chemical Industry.

MacKenzie, S. E., M. E. Savard, et al. (1998). "Isolation of a new fumonisin from Fusarium moniliforme grown in liquid culture." Journal of Natural Products 61(3): 367-369. ://000072852100013 A new fumonisin, iso-fumonisin B-1 (iso-FB1, 1), has been isolated from liquid cultures of the fungus Fusarium moniliforme (Sheldon) NRRL 13616. On the basis of its spectroscopic data, its structure has been determined to differ from that of fumonisin B-1 only in the presence of st hydroxyl function at C-4 instead of C-5.

Magan, N., Russell Hope, Victoria Cairns and David Aldred (2004). "Post-Harvest Fungal Ecology: Impact of Fungal Growth and Mycotoxin Accumulation in Stored Grain." European Journal of Plant Pathology 109(7): 723-730. http://dx.doi.org/10.1023/A:1026082425177 AND http://www.botanischergarten.ch/Bt/Magan-Post-harvest-fungal-2004.pdf Grain quality after harvest is influenced by a wide variety of abiotic and biotic factors and has been studied as a stored grain ecosystem. Important factors include grain and contaminant mould respiration, insects and mites, and the key environmental factors of water availability and temperature. Interactions between these factors influence the dominance of fungi, particularly mycotoxigenic species. Studies have shown that growth, mycotoxin production, competitiveness and niche occupation by mycotoxigenic species are influenced by the presence of other contaminant moulds and environmental factors. This has been demonstrated for both Fusarium culmorum and deoxynivalenol production, Aspergillus ochraceus/Penicillium verruscosum and ochratoxin production and Fusarium section Liseola and fumonisin production. Interactions between mycotoxigenic spoilage fungi and insects do occur but have not been studied thoroughly. Some insects disseminate mycotoxigenic species, others are known to use spoilage moulds as a food source, while others avoid certain fungal species. Thus, a more holistic ecological view is needed when considering management approaches to long-term-safe storage of cereal grains after harvest.

Magan, N., R. Hope, et al. (2003). "Post-harvest fungal ecology: Impact of fungal growth and mycotoxin accumulation in stored grain." European Journal of Plant Pathology 109(7): 723-730. ://000185661500008 Grain quality after harvest is influenced by a wide variety of abiotic and biotic factors and has been studied as a stored grain ecosystem. Important factors include grain and contaminant mould respiration, insects and mites, and the key environmental factors of water availability and temperature. Interactions between these factors influence the dominance of fungi, particularly mycotoxigenic species. Studies have shown that growth, mycotoxin production, competitiveness and niche occupation by mycotoxigenic species are influenced by the presence of other contaminant moulds and environmental factors. This has been demonstrated for both Fusarium culmorum and deoxynivalenol production, Aspergillus ochraceus/Penicillium verruscosum and ochratoxin production and Fusarium section Liseola and fumonisin production. Interactions between mycotoxigenic spoilage fungi and insects do occur but have not been studied thoroughly. Some insects disseminate mycotoxigenic species, others are known to use spoilage moulds as a food source, while others avoid certain fungal species. Thus, a more holistic ecological view is needed when considering management approaches to long-term-safe storage of cereal grains after harvest.

Magg, T., A. E. Melchinger, et al. (2002). "Relationship between European corn borer resistance and concentration of mycotoxins produced by Fusarium spp. in grains of transgenic Bt maize hybrids, their isogenic counterparts, and commercial varieties." Plant Breeding 121(2): 146-154. ://000175211000008 The European corn borer (ECB). Ostrinia nubilalis Hb.. is a major pest of maize in central Europe and promotes the infection of maize with Fusarium spp. In this study, transgenic Bt maize hybrids Acre compared with their isogenic counterparts, and with commercial hybrids from the recommended list with regard to their level of ECB resistance and their concentration of deoxynivalenol (DON). its 15-acetyl (15-A-DON) and 3-acetyl (3-A-DON) derivatives. nivalenol (NIV), fusarenon-X (FUS-X). fumonisins (FUM). and zearalenon (ZEN) in harvested grains. The field experiments Acre performed in Germany at four locations in 1999 and at five locations in 2000. Transgenic Bi hybrids showed significantly lower means than their corresponding isogenic counterparts and than commercial hybrids for all resistance traits: damage rating of stalks. number of larvae per plant. number of larvae per ear, and percentage of damaged plants or ears under infestation. Among all mycotoxins analysed. DON consistently showed the highest concentration across all year x location combinations, Mycotoxin concentrations varied significantly between locations, years and genotypes, whereas mycotoxin concentrations were not significantly different between infested and protected plots. Associations between ECB resistance traits and mycotoxin concentrations were not consistent across years. It is concluded that under central European conditions. the use of Bt maize hybrids will only slightly reduce the contamination of maize kernels with mycotoxins produced by Fusarium spp.

Mahanti, N., D. Bhatnagar, et al. (1996). "Structure and function of fas-1A, a gene encoding a putative fatty acid synthetase directly involved in aflatoxin biosynthesis in Aspergillus parasiticus." Applied and Environmental Microbiology 62(1): 191-195. ://A1996TN22600032 A novel gene, fas-1A, directly involved in aflatoxin B1 (AFB1) biosynthesis, was cloned by genetic complementation of an Aspergillus parasiticus mutant strain, UVM8, blocked at two unique sites in the AFB1 biosynthetic pathway, Metabolite conversion studies localized the two genetic blocks to early steps in the AFB1 pathway (nor-1 and fas-1A) and confirmed that fas-1A is blocked prior to nor-1, Transformation of UVM8 with cosmids NorA and NorB restored function in nor-1 and fas-1A, resulting in synthesis of AFB1. An 8-kb SacI subclone of cosmid NorA complemented fas-1A only, resulting in accumulation of norsolorinic acid, Gene disruption of the fas-1A locus blocked norsolorinic acid accumulation in A, parasiticus B62 (nor-1), which normally accumulates this intermediate, These data confirmed that fas-1A is directly involved in AFB1 synthesis. The predicted amino acid sequence of fas-1A showed a high level of identity with extensive regions in the enoyl reductase and malonyl/palmityl transferase functional domains in the beta subunit of yeast fatty acid synthetase. Together, these data suggest that fas-1A encodes a novel fatty acid synthetase which synthesizes part of the polyketide backbone of AFB1, Additional data support an interaction between AFB1 synthesis and sclerotium development.

Mahfoud, R., M. Maresca, et al. (2002). "pH-dependent interaction of fumonisin B-1 with cholesterol: Physicochemical and molecular modeling studies at the air-water interface." Journal of Agricultural and Food Chemistry 50(2): 327-331. ://000173214500014 Langmuir film balance technology was used to study the interaction between the mycotoxin fumonisin B-1 (FB1) and cholesterol. FB1 was added in the aqueous subphase underneath a monomolecular film of cholesterol, and the interaction was measured as an increase in the surface pressure of the film. Above pH 9, a strong inhibition of the reaction was observed. Similar results were obtained with the bile salt sodium taurocholate. The FB1-cholesterol complex was reinforced by NaCl but was destabilized by NaF, a salt known to break hydrogen bonds. These data suggest that the molecular association between FB1 and cholesterol involves both hydrophobic interactions and a hydrogen bond between the NH3+ group of FB1 and the OH group of cholesterol. Molecular mechanics simulations of the FB1-cholesterol complex were consistent with this hypothesis. These data may shed some light on the mechanisms involved in the intestinal absorption of FB1 and its biliary excretion.

Mahmoud, A. L. E. (1993). "Toxigenic Fungi and Mycotoxin Content in Poultry Feedstuff Ingredients." Journal of Basic Microbiology 33(2): 101- 104. ://A1993LF64200003 AND http://www.botanischergarten.ch/Bt/Mahmoud-Toxigenic-fungi-1993.pdf Fifty isolates of Aspergillus flavus as well as 25 isolates of each of A. fumigatus, A. oclzracezo, A. terrezw and Fusaritl~z spp. isolated from poultry feeds were screened for toxin production. Of these isolates, 20% have been detected to exhibit toxigenic activity. The mycotoxi~l content was determined in samples of grind maize, cotton-seed cake, fish meal, wheat bran and soybean meal. 80% of maize samples were highly contaminated with aflatoxins (480 pg/kg) and zearalenone (40 pg/kg). Aflatoxins B, and B, were found in 50 and 30% of cotton-seed cake and fish meal, respectively. With wheat bran, 40% of the samples contained aflatoxin B, and zearalenone. Soybean meal appeared to be a poor substrate for mycotoxin formation. Mycotoxins are secondary metabolites produced by certain strains of fungi. The presence of these toxins in feed and foodstuffs has becarne a major research area since 1961 when carcinogenicity of aflatoxins was detected. Hundreds of species of more than a dozen f~liigal genera are known to be toxigenic (LOVETT1 972) and these fungi may grow on standing crops or stored feeds (PIERe t al. 1980, MO~IARRAetM nl . 1989). The acculnulating knowledge on aflatoxins and other inycotoxins in grains, seeds, food and feedsturfs and their hazards on human health call for the study of mycotoxins and fungal related problems in aniinal and poultry feedstuffs (SCOTTe t al. 1972, STOLOFF19 76, PURWOKeOt al. 1991). The presence of toxins in feeds affects not only the l~ealtlio f the animals directly, but also liuinan healtli indirectly and thus this problem inay be a threat to public healtli (PENNINGTO1N9 8 6). The present work was designed to study the toxigenic f~lilgi as well as the natural occurrence ‘of inycotoxins in five different ingredients of coinmercial poultry feedstuffs, to estimate the extent of the problem.

Maragos, C. M., M. E. Jolley, et al. (2001). "Fluorescence polarization as a means for determination of fumonisins in maize." Journal of Agricultural and Food Chemistry 49(2): 596-602. ://000167127900011 Fumonisins, mycotoxins produced by certain species of Fusaria, are commonly found worldwide as contaminants in maize. This paper reports the development of a rapid, portable fluorescence polarization-based assay for fumonisins in maize. The assay was based on the competition of unlabeled fumonisin, from a sample, with a fluorescently tagged fumonisin (FB1-FL) for a fumonisin- specific monoclonal antibody in solution. The fluorescence polarization (FP) of the tagged fumonisin was increased upon binding with the antibody. In the presence of free toxin, less of the FB1-FL was bound and the polarization signal was decreased. The assays were very simple to perform, requiring only mixing of an aqueous extract of maize with the tagged fumonisin and antibody, and required <2 min per sample, excluding extraction time. Two permutations of the assay were tested, one with each sample matrix serving as its own blank, and the other with all of the samples compared relative to a PBS blank with normalization of the data similar to an ELISA. The limit of detection, defined as the toxin content associated with a fluorescence polarization signal 5 standard deviations from that of a fumonisin-free control, was 0.5 g of FB1/g in spiked maize. Recoveries from spiked maize over the range of 0.5-20 ppm averaged 94.3 +/- 13.8%. Forty-eight samples of field-contaminated maize were tested by the FP and an established HPLC method, with a good correlation between the two (r(2) = 0.85-0.88). For these samples, the two variations of the FP assay also compared well to one another (r(2) = 0.97), suggesting the assay principle is very robust. The results, combined with the speed and ease of use for the assay, suggest that this technology has substantial potential as a screening tool for mycotoxins in foods.

Maragos, C. M. and S. P. McCormick (2000). "Monoclonal antibodies for the mycotoxins deoxynivalenol and 3- acetyl-deoxynivalenol." Food and Agricultural Immunology 12(3): 181-192. ://000089567100001 The mycotoxin deoxynivalenol (DON) is produced by the mold Fusarium graminearum and is found worldwide on cereal grains, in particular wheat and maize. Each year this compound, also known as `vomitoxin' causes substantial losses to agricultural productivity. Three monoclonal antibodies were developed following the immunization of mice with a conjugate of DON and ovalbumin. One of these antibodies, produced by clone #22, was selected for the development of a competitive direct ELISA (CD- ELISA). This format consists of competition between a DON horseradish peroxidase conjugate (DON-HRP) and free DON for antibody attached to microwell plates. Color development in the assay was inhibited 50% (IC50) by 18 ng DON/ml in phosphate- buffered saline (PBS). The antibody from this clone showed strong cross-reactivity to 3-acetyl deoxynivalenol (3-Ac-DON), with an IC50 of 2.9 ng ml(-1) Cross-reactivity to 19 other trichothecene mycotoxins was low. The CD-ELISA was applied to wheat spiked with DON over the range 0.01-10 mu g/g and extracted with a 10-fold excess of PBS. The midpoint for color development in the assay using this extraction was 0.27 mu g DON/g wheat. Recoveries over the range 0.05-5 mu g/g averaged 88.7% with a coefficient of variation of 10.9%. This assay is sufficiently sensitive and rapid to permit the screening of DON in wheat below the US Food and Drug Administration advisory level of 1 ppm in human food.

Maragos, C. M. and V. S. Thompson (1999). "Fiber-optic immunosensor for mycotoxins." Natural Toxins 7(6): 371-376. ://000166017400022 Evanescent wave-based fiber-optic immunosensors were studied for the detection of fumonisins and aflatoxins in maize. Two formats, competitive and non-competitive, were used. A competitive format was used to measure fumonisin B-1 (FB1) in both spiked and naturally contaminated maize samples. Fumonisin monoclonal antibodies were covalently coupled to an optical fiber and the competition between FB1 and FB1 labeled with fluorescein (FB1-FITC) for the limited number of binding sites on the fiber was assessed. The signal generated in the assay was inversely proportional to the FB1 concentration. For samples, the concentration causing an inhibition of binding by 50% (IC50) was dependent upon the clean-up procedure used. Simple dilution of methanolic maize extracts yielded an assay with an IC50 equivalent to 25 mug FB1 g(-1) maize with a limit of detection of 3.2 mug g(-1) maize. Affinity column clean-up yielded an assay with an IC50 equivalent to 5 mug FB, g(-1) maize (limit of detection 0.4 mug FB1 g(-1)). An HPLC method and the immunosensor method agreed well for naturally contaminated maize samples except when large amounts of other fumonisins that cross-react with the immunosensor were present. The second sensor format, for the mycotoxin aflatoxin B-1 (AFB(1)), was a non-competitive assay using the native fluorescence of this mycotoxin. Because the fluorescence of AFB1 itself was detected, the response of the sensor was directly proportional to the toxin concentration. The sensor, while capable of detecting as little as 2 ng ml(-1) of AFB(1) in solution was technically not an immunosensor, since the attachment of aflatoxin specific antibodies was not required. Sensors of the formats described have the potential to rapidly screen individual maize samples but require coupling with a clean-up technique to be truly effective. Published in 1999 by John Wiley & Sons, Ltd.

Marasas, W. F. O. (1993). "Occurrence of Fusarium-Moniliforme and Fumonisins in Maize in Relation to Human Health." South African Medical Journal 83(6): 382-383. ://A1993LG35800008

Marasas, W. F. O. (1995). "Fumonisins - History, Worldwide Occurrence and Impact." Abstracts of Papers of the American Chemical Society 209: 56-AGFD. ://A1995QP23200056

Marasas, W. F. O. (1997). "Risk assessment of fumonsins produced by Fusarium moniliforme in corn." Cereal Research Communications 25(3): 399-406. ://A1997YE35700045 Four important toxigenic species of fungi are associated with corn (Zea mays) intended for human and animal consumption in South Africa, ie Aspergillus flavus, Diplodia maydis, Fusarium graminearum, and Fusarium moniliforme. Corn infected by these fungi causes outbreaks of the following mycotoxicoses in animals: aflatoxicosis, diplodiosis, hyperestrogenism and leukoencephalomalacia. The five most important mycotoxins known to occur naturally in corn in South Africa are aflatoxins, deoxynivalenol, nivalenol, zearalenone and fumonisins. The following mycotoxins in foods have been implicated in human diseases in South Africa: aflatoxins in acute toxic hepatitis, kwashiorkor and liver cancer and fumonisins in oesophageal cancer. Tolerance levels of mycotoxins in grain are essential to protect human health and to assess grain quality from the viewpoint of mycotoxin contamination. Tolerance levels are established by means of risk assessment studies. Risk assessment of mycotoxins in grains has two major components, ie exposure assessment and hazard assessment. Exposure is calculated from naturally occurring levels of a mycotoxin in foodstuffs and food intake and expressed as the Probable Daily Intake (PDI). Hazard is calculated from toxicological studies in experimental animals by dividing the No Observed Effect Level (NOEL) by a Safety Factor (ranging from 100 to 5000) and expressed as the Tolerable Daily Intake (TDI). Several estimates of PDI and TDI values of fumonisins in corn are compared and a tolerance level of 100 to 200 mu g/kg for fumonisins in corn intended for human consumption is suggested. However, more work remains to be done to establish scientifically sound and economically reasonable tolerance levels for fumonisins in corn.

Marasas, W. F. O. (2001). "Discovery and occurrence of the fumonisins: A historical perspective." Environmental Health Perspectives 109(2 supplement): 239-243. ://WOS:000168824500009 AND http://www.botanischergarten.ch/Bt/Marasas-Discovery-Fumonisins-2001.pdf This article describes the events leading to the discovery of the fumonisins in South Africa in 1988 and highlights the first 10 years (1988-1998) of fumonisin research. The predominant fungus isolated from moldy corn implicated in a field outbreak of equine lekoencephalomalacia (ELEM) in South Africa in 1970 was Fusarium verticillioides(F. moniliforme). This fungus was also prevalent in moldy home-grown corn consumed by people in high-incidence areas of esophageal cancer (EC) in the Transkei region of South Africa. Culture material on corn of F. verticillioides strain MRC 826, which was isolated from moldy corn in Transkei, was shown to cause ELEM in horses, porcine pulmonary edema (PPE) syndrome in pigs, and liver cancer in rats. A short-term cancer initiation/promotion assay in rat liver was used to purify the carcinogen(s) in the culture material. These efforts finally met with success when fumonisins B-1 and B-2, novel mycotoxins with cancer-promoting activity in rat liver, were isolated from culture material of F. verticillioides MRC: 826 at the Programme on Mycotoxins and Experimental Carcinogenesis of the Medical Research Council in Tygerberg. South Africa. Following the elucidation of the chemical structure of the fumonisins, these carcinogenic mycotoxins were shown to occur naturally in moldy corn in Transkei. Shortly thereafter, high levels of fumonisins in the 1989 U.S. corn crop resulted in large-scale field outbreaks of ELEM and PPE in horses and pigs, respectively, in the United States. Subsequently the fumonisins were found to occur naturally in corn worldwide, including corn consumed as the staple diet by people at high risk for EC in Transkei and China. These findings, together with the fact that the fumonisins cause field outbreaks of mycotoxicoses in animals, are carcinogenic in rats, and disrupt sphingolipid metabolism, have resulted in much worldwide interest in these compounds during the first 10 years after the discovery of the fumonisins in 1988.

Marasas, W. F. O., T. S. Kellerman, et al. (1988). "Leukoencephalomalacia in a Horse Induced by Fumonisin-B1 Isolated from Fusarium- Moniliforme." Onderstepoort Journal of Veterinary Research 55(4): 197-203. ://A1988U100900002

Marasas, W. F. O., N. P. J. Kriek, et al. (1977). "Occurrence of Zearalenone and Deoxynivalenol, Mycotoxins Produced by Fusarium- Graminearum Schwabe, in Maize in Southern- Africa." South African Journal of Science 73(11): 346-349. ://A1977EC91400066

Marasas, W. F. O., R. T. Riley, et al. (2004). "Fumonisins disrupt sphingolipid metabolism, folate transport, and neural tube development in embryo culture and in vivo: A potential risk factor for human neural tube defects among populations consuming fumonisin-contaminated maize." Journal of Nutrition 134(4): 711-716. ://000220681700002 AND http://www.botanischergarten.ch/Bt/Marasas-Fumonisin-Review-2004.pdf Fumonisins are a family of toxic and carcinogenic mycotoxins produced by Fusarium verticillioides (formerly Fusarium moniliforme), a common fungal contaminant of maize. Fumonisins inhibit ceramide synthase, causing accumulation of bioactive intermediates of sphingolipid metabolism (sphinganine and other sphingoid bases and derivatives) as well as depletion of complex sphingolipids, which interferes with the function of some membrane proteins, including the folate-binding protein (human folate receptor a). Fumonisin causes neural tube and craniofacial defects in mouse embryos in culture. Many of these effects are prevented by supplemental folic acid. Recent studies in LMBc mice found that fumonisin exposure in utero increases the frequency of developmental defects and administration of folate or a complex sphingolipid is preventive. High incidences of neural tube defects (NTD) occur in some regions of the world where substantial consumption of fumonisins has been documented or plausibly suggested (Guatemala, South Africa, and China); furthermore, a recent study of NTD in border counties of Texas found a significant association between NTD and consumption of tortillas during the first trimester. Hence, we propose that fumonisins are potential risk factors for NTD, craniofacial anomalies, and other birth defects arising from neural crest cells because of their apparent interference with folate utilization.

Marasas, W. F. O., S. J. Vanrensburg, et al. (1979). "Incidence of Fusarium Species and the Mycotoxins, Deoxynivalenol and Zearalenone, in Corn Produced in Esophageal Cancer Areas in Transkei." Journal of Agricultural and Food Chemistry 27(5): 1108-1112. ://A1979HL82200044

Marasas, W. F. O. and H. F. Vismer (2003). "Food for thought about mycotoxins, organic and genetically modified foods." Advances in Stored Product Protection: 423-427. ://BIOSIS:PREV200600077168 Food safety is an issue that is becoming increasingly important in national and international debates about agriculture, nutrition and health. Food safety is a complex and many-faceted issue. Three of these facets are food-borne toxic metabolites of fungi (mycotoxins), organically grown foods (organic foods) and genetically modified foods (GM-foods). Although there are different definitions and perceptions of "organic agriculture", the fact is that there is an increasing demand for organic foods in developed countries. Some people may argue that people in developing countries have always been eating organic foods. Be that as it may, the fact is that foods that are grown without the use of insecticides and fungicides may be expected to be infested by insects and infected by fungi to a larger extent than conventionally grown foods and concomitantly contaminated with higher levels of mycotoxins. A good example of this situation is patulin produced by the postharvest fungus, Penicillium expansum, in damaged or stored apples. In the case of conventionally grown apples, patulin levels in apple juice have been reported to range from 240-4000 mu g/L. Conversely, in organically produced apple cider, levels of up to 45,000 mu g/L were found. In organically produced apples, fewer apples were marketable, fungal rot was higher and the incidence of particularly P. expansum was increased over a short storage period. On the other hand, significant reductions in fumonisins produced by Fusarium verticillioides and F. proliferatum in genetically modified Bt-maize hybrids compared with standard maize lines have been achieved. Toxin-producing fungi, including Aspergillus flavus, A. ochraceaus, Fusarium verticillioides, F. graminearum, Penicillium expansum and their mycotoxins, such as aflatoxin B I, fumonisins and patulin, have been noted to occur in health foods such as nuts, oilseeds, muesli, cereals and partially milled rice, further posing a threat to human health. Serious health risks, such as liver cancer, may arise where mycotoxins are not controlled effectively in bulk productions of food commodities, such as aflatoxin in peanut butter. Recently, peanut butter used in the Primary Schools Nutrition Programme in South Africa was reported to contain high levels of aflatoxin. It is of great concern that the liver-cancer risk increases significantly if a child with hepatitis B infection consumes aflatoxin-contaminated foodstuffs such as peanut butter at school and/or subsistence home-grown peanuts at home. The statistics for mycotoxins in organic and health foods in South Africa and many other countries worldwide are still very limited, and should be further researched. The use of fungi and yeasts as biocontrol measures is also of concern, due to the emergence of fungi previously not considered important in human disease. In summary, it can be said that mycotoxin levels are generally higher in organically grown crops; that genetically modified crops can reduce mycotoxin levels significantly; that pesticides, in cases where insect infestations lead to fungal infections, reduce mycotoxin contamination; that fungicides are applied to control plant pathogenic fungi, and consequently lead to mycotoxin reduction; and that biological control is a concern with regard to emerging medically important fungi and the immune-compromised human host, as is the case in HIV/AIDS.

Marin, S., X. Albareda, et al. (2001). "Impact of environment and interactions of Fusarium verticillioides and Fusarium proliferatum with Aspergillus parasiticus on fumonisin B-1 and aflatoxins on maize grain." Journal of the Science of Food and Agriculture 81(11): 1060-1068. ://000170434400002 Fusarium verticillioides and F proliferatum isolates were inoculated in mixed cultures with Aspergillus parasiticus on irradiated maize grain at two different inoculum concentrations (2 x 10(5) and 2 x 10(2) conidia g(-1) dry maize). The treatments were 0.93-0.98 water activity (a(w)) and 15 and 25 degreesC for 28 days. A complex relationship was found between a(w), temperature, inoculum concentration and the interactions which took place between fumonisin and aflatoxin producers. In general, A parasiticus reduced F verticillioides and F proliferatum populations (by 6-36%) but did not affect fumonisin B-1 production by these species. In contrast, while the Fusarium species were not able to decrease A parasiticus populations, they significantly reduced aflatoxin B-1 accumulation (by 30-93%). (C) 2001 Society of Chemical Industry.

Marin, S., N. Magan, et al. (2000). "Selective effect of propionates and water activity on maize mycoflora and impact on fumonisin B-1 accumulation." Journal of Stored Products Research 36(2): 203-214. ://000086150400011 The effect of a commercial mixture of propionates at two different doses (0.05% and 0.1%) on fungal spoilage of natural maize stored at 0.85, 0.90 and 0.95 water activity (a(w),) was investigated. Parallel treatments with added inoculum of Fusarium Liseola section isolates (Fusarium moniliforme and F. proliferatum) were carried out in order to determine the effect of fungal interactions on the development of fumonisin- producers on maize in relation to preservative efficacy. Fungal colonisation of grain was measured as fungal counts (CFUs g(-1) maize). In general, no differences were found between inoculated and uninoculated samples. Besides the selective effect of a(w) on maize mycoflora, it was demonstrated that most genera which colonise maize remained unaffected by the preservative concentrations applied. However, Penicillium populations (CFUs g(-1) maize) counts decreased significantly. As they represent a major component of the total fungal counts, an overall control of total mycoflora was observed. Furthermore, there was a significant statistical interaction between preservative and a(w) levels, with the preservative activity enhanced at low a(w). The concentrations of fumonisin B-1(-) were unaffected by treatment with no significant differences in concentrations found. This suggests that the natural mycoflora of maize may act as an inhibitor of Fusarium development, and consequently of fumonisin biosynthesis. (C) 2000 Elsevier Science Ltd. All rights reserved.

Marin, S., V. Sanchis, et al. (1998). "Colonization of maize grain by Fusarium moniliforme and Fusarium proliferatum in the presence of competing fungi and their impact on fumonisin production." Journal of Food Protection 61(11): 1489-1496. ://000076988500012

Marin, S., A. Velluti, et al. (2003). "Control of fumonisin B-1 accumulation in naturally contaminated maize inoculated with Fusarium verticillioides and Fusarium proliferatum, by cinnamon, clove, lemongrass, oregano and palmarosa essential oils." European Food Research and Technology 217(4): 332-337. ://000185809500012 The effect of cinnamon, clove, oregano, palmarosa and lemongrass oils on fumonisin B-1 (FB1) accumulation by one isolate each of Fusarium verticillioides and Fusarium proliferatum in non-sterilised naturally contaminated maize grain at 0.995 and 0.950 a(w) and at 20 and 30 degreesC was evaluated. The concentration used was 500 mg kg(-1) maize. Under these conditions it was shown that antimycotoxigenic ability only took place at the higher water availabilities, and mostly at 20 degreesC. Only cinnamon, lemongrass and palmarosa oils were somewhat effective. Moreover, it was suggested that competing mycoflora plays an important role in FB1 accumulation. It was concluded that the efficacy of essential oils in real substrates, such as cereals, may be much lower than in synthetic media; different essential oils may be found to be useful and at different concentrations. Their effectiveness is highly dependent on both abiotic and biotic factors involved.

Marnewick, J. L., W. Batenburg, et al. (2004). "Ex vivo modulation of chemical-induced mutagenesis by subcellular liver fractions of rats treated with rooibos (Aspalathus linearis) tea, honeybush (Cyclopia intermedia) tea, as well as green and black (Camellia sinensis) teas." Mutation Research-Genetic Toxicology and Environmental Mutagenesis 558(1-2): 145-154. ://000220006800016 Male Fischer rats were given unprocessed (not oxidized) and processed (oxidized) rooibos and honeybush teas as well as,green and black teas as a sole source of drinking fluid for 10 weeks, and sub cellular liver fractions were prepared. Cytosolic fractions of rats consuming the unprocessed herbal teas, green and black teas significantly (P < 0.05) protected against 2-acetylaminofluorene (2- AAF)-induced mutagenesis in the Salmonella mutagenicity test with strain TA 98, using Aroclor 1254-induced microsomes. A marginal or no protection was obtained with the processed herbal teas. The mutagenic response of aflatoxin B-1 (AFB(1)) against Salmonella strain TA 100 was significantly (P < 0.05) inhibited by cytosolic fractions from rats treated with processed and unprocessed herbal teas, while no effect was obtained with the green and black teas. Microsomal fractions prepared from livers of rats treated with both the processed and unprocessed rooibos teas and the unprocessed honeybush tea, significantly (P < 0.05) reduced the activation of AFB(1) while no protection was observed against 2-AAF-induced mutagenesis. In contrast, microsomal fractions from rats treated with the green, black and unprocessed honeybush teas significantly (P < 0.05) enhanced the mutagenic response of 2-AAE None of the tea treatments significantly affected the concentration of the microsomal liver cytochrome P450. (C) 2004 Elsevier B.V. All rights reserved.

Marnewick, J. L., W. C. A. Gelderblom, et al. (2000). "An investigation on the antimutagenic properties of South African herbal teas." Mutation Research-Genetic Toxicology and Environmental Mutagenesis 471(1-2): 157-166. ://000165418800017 The antimutagenic properties of South African herbal teas were investigated using the Salmonella typhimurium mutagenicity assay. Aqueous extracts of fermented and unfermented rooibos tea (Aspalathus linearis) and honeybush tea (Cyclopia intermedia) both possess antimutagenic activity against 2- acetylaminofluorene (2-AAF) and aflatoxin B-1 (AFB(1))-induced mutagenesis using tester strains TA98 and TA100 in the presence of metabolic activation. A far less inhibitory effect was noticed against the direct acting mutagens, methyl methanesulfonate (MMS), cumolhydroperoxide (CHP), and hydrogen peroxide (H2O2) using TA102, a strain designed to detect oxidative mutagens and carcinogens. Depending on the mutagen used, the unfermented tea exhibited the highest protective effect. A similar response regarding the protection against mutagenesis was obtained when utilising different variations of the double layer Salmonella assay. The double layer technique proved to be more effective to detect the protective effect of the different tea preparations against the direct acting mutagens. With respect to indirect mutagens, the highest protection was noticed when the carcinogen was metabolically activated in the presence of the tea extract as compared with when the tea extract was incubated in a separate layer with the bacteria. The current data suggest that two mechanisms seem to be involved in the antimutagenicity of the tea extracts towards carcinogens that require metabolic activation: (i) the tea components may interfere with cytochrome P350-mediated metabolism of these mutagens and (ii) the direct interaction between the tea constituents, presumably the polyphenolic compounds, with the promutagens and/or the active mutagenic metabolites. However, the mild and/or lack of protection and in some cases even enhancement of mutagenesis induced by direct acting or oxidative mutagens, provide new perspectives regarding the role of the polyphenolic compounds known to exhibit antioxidant properties, in the protection against mutagenesis in the Salmonella assay. The present study provides the first evidence on the antimutagenic activity of honeybush tea and further evidence on the antimutagenicity of rooibos tea. (C) 2000 Elsevier Science B.V. All rights reserved.

Masoero, F., M. Moschini, et al. (1999). "Nutritive value, mycotoxin contamination and in vitro rumen fermentation of normal and genetically modified corn (cry1A(b)) grown in northern Italy." Maydica 44(3): 205-209. ://000083838800003 AND http://www.botanischergarten.ch/Bt/Masoero-Mycotoxin-Contam-1999.pdf An assessment was made on the effect of inserting the cry1A(b) (Bt) gene of Bacillus thuringiensis into the genoma of two corn hybrids (the newly-developed hybrid from Cargill Semences identified as CR and the traditional B73xMo17) on the analytical composition, the in vitro rumen degradability and the mycotoxin contamination of the plant. Transgenicity changed the plant chemical composition as a function of the recipient genotype: starch was increased in the CR-Bt(+) plant (70.4% vs 73.3%; P < 0.10) whereas higher lignin content (6.3% vs 7.3%; P < 0.05), lower protein 7.7% vs 7.1%; (P < 0.10) and soluble nitrogen (34.8% vs 26.9%; P < 0.10) contents a ere observed for the B73xMo17-Bt(+) plants. When not considering the hybrid pedigree there was a tendency (p < 0.1) toward a lower protein content in the Bt(+) corn seeds (9.2 re 8.2%) and a higher sugar content in stalk and leaves (2.9% vs 5.7%). The stover degradation increased in the CR-Bt(+) variety, probably as the consequence of the higher content of lower structured carbohydrates. Transgenic plants had less ergosterol and fumonisin content than standard corn, suggesting a reduced susceptibility to mould attack.

Matsushima, K., P. K. Chang, et al. (2001). "Pre-termination in aflR of Aspergillus sojae inhibits aflatoxin biosynthesis." Applied Microbiology and Biotechnology 55(5): 585-589. ://000168912600011 The aflR gene product is the main transcriptional regulator of aflatoxin biosynthesis in Aspergillus parasiticus and Aspergillus flavus. Although A. sojae strains do not produce aflatoxins, they do have an aflR homologue. When compared with the aflR of A. parasiticus, the A. sojae gene contains two mutations: an HAHA motif and a premature stop codon. To investigate the functionality of the A. sojae aflR gene product, we used a GAL4 one-hybrid system in yeast. The transcription-activating activity of AflR from A. sojae was 15% of that from A. pamsiticus. The introduction of an additional aflR from A. sojae into an A. parasiticus strain did not affect aflatoxin productivity. A hybrid aflR comprising the amino- terminal region of A. sojae aflR and the carboxy-terminal region of A. parasiticus aflR suppressed the effect associated with pre-termination of the A. sojae AflR. We conclude that the premature stop codon of the A. sojae aflR is the key to its functionality and leads to prevention of aflatoxin biosynthesis through loss of the transcription of aflatoxin biosynthesis- related genes.

Maupin, L. M., M. J. Clements, et al. (2003). "Evaluation of the M182 corn line as a source of resistance to aflatoxin in grain and use of BGYF as a selection tool." Plant Disease 87(9): 1059-1066. ://000184975100008 Our objectives were to determine if the corn (Zea mays) inbred M182 has alleles for resistance to Aspergillus ear rot (caused by Aspergillus flavus) and aflatoxin accumulation in grain that can be transferred to commercially used inbreds, and to determine the types and magnitudes of gene action. heritabilities, and gain from selection for low levels of bright greenish-yellow fluorescence (BGYF). aflatoxin. and ear rot with M182. Also, we hoped to determine if selection against BGYF would substantially reduce the concentration of aflatoxin in grain. Primary ears and ground grain from inbred M182 (P-1), the susceptible inbred B73 (P-2), and the F-1, F-2, F-3, BCP1S1, and BCP2S1 generations developed from these inbreds were evaluated for BGYF, concentration of aflatoxin in grain, and severity of Aspergillus ear rot in 2000 and 2001. Dominance was the most important gene action associated with low levels of BGYF and a low concentration of aflatoxin in grain. Heritabilities for low levels of BGYF (83.5%), aflatoxin (74.1%), and car rot (62.8%) were high. Correlation coefficients between aflatoxin and BGYF were high in both years (r = 0.75 and 0.79 for 2000 and 2001, respectively). Unlike aflatoxin, BGYF was not affected by the year in which plants were grown. Selection for low levels of BGYF prior to selection based on aflatoxin concentration is as effective as selection for either factor alone. M182 has value in programs designed to improve the resistance of commercially used corn inbreds.

Mayer, Z., A. Bagnara, et al. (2003). "Quantification of the copy number of nor-1, a gene of the aflatoxin biosynthetic pathway by real-time PCR, and its correlation to the cfu of Aspergillus flavus in foods." International Journal of Food Microbiology 82(2): 143-151. ://000181786700006 A real-time PCR system directed against the nor-1 gene of the aflatoxin biosynthetic pathway as a target sequence has been applied to detect an aflatoxinogenic A. flavus strain in plant- type foods like maize, pepper and paprika. The system is based on the TaqMan((R)) fluorescent probe technology. The copy numbers of the nor-1 gene were compared to conventional cfu data obtained from the same set of samples. In general, a good correlation between nor-1 gene copy number and the cfu data was observed; however, the nor-1 copy numbers were always higher. It was shown that the system is specific for nor-1 containing species. (C) 2002 Elsevier Science B.V. All rights reserved.

McCormick, S. P., D. Bhatnagar, et al. (1988). "An Inhibitor of Aflatoxin Biosynthesis in Developing Cottonseed." Canadian Journal of Botany- Revue Canadienne De Botanique 66(5): 998-1002. ://A1988N573100026

McCormick, S. P., D. Bhatnagar, et al. (1987). "Averufanin Is an Aflatoxin-B1 Precursor between Averantin and Averufin in the Biosynthetic- Pathway." Applied and Environmental Microbiology 53(1): 14-16. ://A1987F513700004

McCormick, S. P., E. Bowers, et al. (1988). "High-Performance Liquid-Chromatographic Procedure for Determining the Profiles of Aflatoxin Precursors in Wildtype and Mutant Strains of Aspergillus-Parasiticus." Journal of Chromatography 441(2): 400-405. ://A1988N998100019

McGeoch, M. A. and K. L. Pringle (2005). "Science and advocacy: the GM debate in South Africa." South African Journal of Science 101(1-2): 7- 9. ://000229423000004 AND http://www.botanischergarten.ch/Bt/McGeoch-Science-Avocacy-2005.pdf SOUTH AFRICA HAS AN EFFECTIVE regulatory framework for transgenics, and its rate of adopting genetic modification technology is amongst the highest in the world. However, the ecological consequences of introducing genetically modified organisms in this country have not been systematically explored. It is critical to do so if we are to continue to make informed choices on the extent to which the technology should be adopted.

McGlynn, K. A., K. Hunter, et al. (2003). "Susceptibility to aflatoxin B-1-related primary hepatocellular carcinoma in mice and humans." Cancer Research 63(15): 4594-4601. ://000184562500045 The genetic basis of disease susceptibility can be studied by several means, including research on animal models and epidemiological investigations in humans. The two methods are infrequently used simultaneously, but their joint use may overcome the disadvantages of either method alone. We used both approaches in an attempt to understand the genetic basis of aflatoxin B-1 (AFB(1))-related susceptibility to hepatocellular carcinoma (HCC). Ingestion of AFB(1) is a major risk factor for HCC in many areas of the world where HCC is common. Whether humans vary in their ability to detoxify the active intermediate metabolite of AFB(1), AFB(1)-exo-8,9-epoxide, is not certain but may explain why all exposed individuals do not develop HCC. To determine whether human variability in detoxification may exist, in a study of 231 HCC cases and 256 controls, we genotyped eleven loci in two families of AFB(1) detoxification genes; the glutathione S-transferases (GSTs) and the epoxide hydrolases (EPHX). After adjustment for multiple comparisons, only one polymorphism in the epoxide hydrolase family 2 locus remained significantly associated with HCC (odds ratio = 2.06, 95% confidence interval = 1.13-3.12). To determine whether additional susceptibility loci exist, we developed a mouse model system to examine AFB(1)-induced HCC. Susceptibility of 7-day-old mice from two common inbred strains (C57BL/6J, DBA/2J) was assessed. DBA/2J animals were 3-fold more sensitive to AFB(1)-induced HCC and significantly more sensitive to AFB(1) acute toxicity than were C57BL/6J animals. Analysis of the xenobiotic metabolizing genes in the, two strains revealed single nucleotide polymorphisms in three genes, Gsta4, Gstt1, and Ephx1. Although the GSTT1 and EPHX1 loci did not appear to be related to HCC in the total population of the human study, a polymorphism in GSTA4 was significantly related to risk in the male subset. The mouse model also demonstrated that absent or compromised p53 was not necessary for the development of carcinogenesis. These results indicate that the comparison of results from human studies and the AFB(1)-susceptible mouse model may provide new insights into hepatocarcinogenesis.

McGlynn, K. A., E. A. Rosvold, et al. (1995). "Susceptibility to Hepatocellular-Carcinoma Is Associated with Genetic-Variation in the Enzymatic Detoxification of Aflatoxin B-1." Proceedings of the National Academy of Sciences of the United States of America 92(6): 2384-2387. ://A1995QM40800123 and http://www.botanischergarten.ch/Mycotoxins/McGlynn-Carcin-Aflatox-1995.pdf Aflatoxin B-1 (AFB(1)) has been postulated to be a hepatocarcinogen in humans, possibly by causing p53 mutations at codon 249. AFB(1) is metabolized via the phase I and II detoxification pathways; hence, genetic variation at those loci may predict susceptibility to the effects of AFB(1). To test this hypothesis, genetic variation in two AFB(1) detoxification genes, epoxide hydrolase (EPHX) and glutathione S-transferase M1 (GSTM1), was contrasted with the presence of serum AFB(1)- albumin adducts, the presence of hepatocellular carcinoma (HCC), and with p53 codon 249 mutations. Mutant alleles at both loci were significantly overrepresented in individuals with serum AFB(1)-albumin adducts in a cross-sectional study. Mutant alleles of EPHX were significantly overrepresented in persons with HCC, also in a case-control study. The relationship of EPHX to HCC varied by hepatitis B surface antigen status and indicated that a synergistic effect may exist. p53 codon 249 mutations were observed only among HCC patients with one or both high-risk genotypes. These results indicate that individuals with mutant genotypes at EPHX and GSTM1 may be at greater risk of developing AFB(1) adducts, p53 mutations, and HCC when exposed to AFB(1). Hepatitis B carriers with the high- risk genotypes may be an even greater risk than carriers with low-risk genotypes. These findings support the existence of genetic susceptibility in humans to the environmental carcinogen AFB(1) and indicate that there is a synergistic increase in risk of HCC with the combination of hepatitis B virus infection and susceptible genotype.

McGlynn, K. A., L. Tsao, et al. (2001). "International trends and patterns of primary liver cancer." International Journal of Cancer 94(2): 290- 296. ://000171045900021 Primary liver cancer (PLC) is common in many areas of the developing world, but uncommon in most of the developed world. Some evidence suggests, however, that the global pattern of PLC may be changing. To clarify this issue, we examined incidence rates for PLC over the 15-year time period, 1978-92, in selected cancer registries around the world. With some exceptions, developed countries have experienced PLC increases in incidence whereas developing countries have experienced declines. Although the reasons for the trends are not entirely clear, the increased seroprevalence of HCV in the developed world and the elimination of HBV-cofactors in the developing world are likely to have contributed to the patterns. Further progress against PLC may be seen in the developing world once the HBV-vaccinated segment of the population reaches adulthood.

McGuire, S. M., J. C. Silva, et al. (1996). "Purification and characterization of versicolorin B synthase from Aspergillus parasiticus. Catalysis of the stereodifferentiating cyclization in aflatoxin biosynthesis essential to DNA interaction." Biochemistry 35(35): 11470-11486. ://A1996VF23600027 The absolute configuration of the dihydrobisfuran ring system characteristic of aflatoxin B-1 is essential to the covalent reaction of its metabolically activated form with double- stranded DNA. The biosynthesis of this potent mycotoxin proceeds through three configurationally labile intermediates to racemic versiconal hemiacetal. Subsequent enzymatic cyclization establishes the stereochemistry of this critical ring fusion in (-)-versicolorin B and is catalyzed by versicolorin B synthase (VBS). The isolation and purification of VBS from Aspergillus parasiticus (SU-1, ATCC 56775) and its kinetic characterization and attempted inactivation are described. Initial purification trials were plagued both by a chromophoric impurity which was difficult to remove and by low recoveries of active protein. The discovery of a remarkably broad pH range of enzyme stability and catalytic activity led to an efficient procedure involving preparative isoelectric focusing and ion exchange FPLC chromatography, The enzyme behaved as a dimer upon gel filtration and migrated with M(r) 78 000 Da during denaturing gel electrophoresis. The UV spectrum of pure VBS gave no evidence of a bound chromophore. Detailed kinetic analysis of VBS revealed that this protein selects from two equilibrating enantiomers of versiconal hemiacetal to cyclize the appropriate antipode to optically pure versicolorin B. By varying the amount of enzyme to a fixed concentration of substrate, the rate of enzymic cyclization could be limited by the intrinsic rate of enantiomerization of the substrate under the conditions of reaction. It was possible to quantitate the dynamics of this substrate enantiomerization/cyclization process, to establish the role played by VBS, and to evaluate the significance of each to the overall biosynthesis of aflatoxin. The potential role of an acidic residue of the enzyme in catalysis was supported by analysis of the pH-rate profile of VBS and chemical labeling studies. Successful demonstration of competitive inhibition of VBS by a simple substrate analogue led to the design and synthesis of a potential mechanism-based inactivator of the protein.

Medina-Martinez, M. S. and A. J. Martinez (2000). "Mold occurrence and aflatoxin B-1 and fumonisin B-1 determination in corn samples in Venezuela." Journal of Agricultural and Food Chemistry 48(7): 2833-2836. ://000088319600038 Fumonisins are mycotoxins produced mainly by Fusarium moniliforme and Fusarium proliferatum, which have been associated with several animal and human diseases. Aflatoxins are hepatotoxic, mutagenic, and teratogenic metabolites produced by Aspergillus flavus and Aspergillus parasiticus. Both have been reported at high levels in corn. This study was pursued to determine mold, aflatoxin B-1 (AFTB(1)), and fumonisin B-1 (FB1) levels in white and yellow corn. Mold levels were determined using potato dextrose agar and identification of the main genus of molds present in corn, AFTB(1) levels by immunoaffinity chromatography, and FB1 levels by a Bond-Elut SAX cartridge and HPLC. AFTB(1) and FB1 occurrences were 16.6 and 83.78%, respectis; ely. The yellow corn presented higher mold incidence than the white corn. A. flavus and F. moniliforme were isolated. The positive results show the importance of this study, corn being the main cereal consumed in the Venezuelan diet.

Meister, U. (2001). "Investigations on the change of fumonisin content of maize during hydrothermal treatment of maize. Analysis by means of HPLC methods and ELISA." European Food Research and Technology 213(3): 187-193. ://000171268200006 The study was subjected to the investigation of the effects of extrusion cooking, gelatinization, and cornflaking on the stability of fumonisins in artificially contaminated maize grits, spiked with fumonisin B-1 and B-2 at levels of 2 mg/kg and 0.6 mg/kg, respectively. All the processed samples were analyzed according to the AOAC-HPLC method, and some selected samples were analyzed additionally by a commercial enzyme- linked immunosorbent assay (ELISA) and after alkaline hydrolysis. All the samples showed significant decreases of the fumonisin levels. If analyzed according to AOAC-HPLC method, cooking extrusion and gelatinization reduced fumonisin levels to approximately 30-55%, cooking the grits for flaking to approximately 20-65%, and roasting the flakes to approximately 6-35% (depending on the selected technological parameters). With ELISA the fumonisin contents were 15-50% and after alkaline hydrolysis 19-380% higher than with the AOAC-HPLC method. However, the funionisin amount added before the technological tests could not be recovered in any of the samples.

Meister, U., H. Symmank, et al. (1996). "Investigation and evaluation of the contamination of native and imported cereals with fumonisins." Zeitschrift Fur Lebensmittel-Untersuchung Und-Forschung 203(6): 528-533. ://A1996WB68200007

Melcion, D., B. Cahagnier, et al. (1997). "Influence of temperature and water activity on fumonisins and fungal biomass production by Fusarium on maize grains." Cereal Research Communications 25(3): 371-373. ://WOS:A1997YE35700036

Melcion, D., B. Cahagnier, et al. (1998). "Influence of temperature on fumonisin B1 production on maize grain by Fusarium proliferatum." Sciences Des Aliments 18(3): 301-311. ://WOS:000075471700005

Melcion, D., B. Cahagnier, et al. (1997). "Study of the biosynthesis of fumonisins B1, B2 and B3 by different strains of Fusarium moniliforme." Letters in Applied Microbiology 24(4): 301-305. ://WOS:A1997WV22400016

Mendez-Albores, J. A., V. G. Arambula, et al. (2003). "Effect of high moisture maize storage on tortilla quality." Journal of Food Science 68(5): 1878-1881. ://000183947000056 We evaluate the effect of high moisture content (MC) stored maize grain on tortilla quality and on the growth of toxigenic fungi. Maize with a MC of 18% was stored for 10, 15, and 20 d at 28 degreesC. The control seed was stored 20 d with a MC of 10.7% at 4 degreesC. The high MC: grain and the control were processed using the traditional nixtamalization process. Storage conditions had-a significant effect on tortilla quality parameters such as pH, color, tensile strength, cut force, viscosity peak, starch retrogradation (setback), and aflatoxin contamination. Tortillas produced with high MC grain presented a lower quality than those,produced with low MC grain.

Mendez-Albores, J. A., G. Arambula-Villa, et al. (2004). "Aflatoxins' fate during the nixtamalization of contaminated maize by two tortilla- making processes." Journal of Stored Products Research 40(1): 87-94. ://000185788300008 The fate of aflatoxin B-1 and B-2 was studied during maize nixtamalization by two tortilla-making processes. High-quality maize seed (AS-900) was used, as well as a toxigenic strain of Aspergillus flavus. The grain moisture content was adjusted to 18%, and the incubation temperature was 27degreesC. One lot of grain served as the control and so was not inoculated with the fungus. At the end of the 13 d incubation period, this control lot was aflatoxin free (aflatoxin level 1). Two other lots were inoculated with the fungus and incubated for 12 and 14 d. They then had aflatoxin contamination of 29 and 93 ppb, respectively (aflatoxins levels 2 and 3). The quantification of aflatoxins was undertaken according to the AOAC Official Method 991.31 and their identification confirmed by HPLC. The maize grain was processed by the traditional (TNP) and the ecological (ENP) nixtamalization processes. Aflatoxins were quantified at all steps of the tortilla-making processes. The research was conducted under a completely randomized factorial design (2 x 3). In the case of tortillas processed with TNP, the total aflatoxin content was 2 and 9 ppb corresponding to aflatoxin levels 2 and 3 with a degradation rate of 92% and 90%, respectively. In tortillas obtained through the ENP, the aflatoxin content was 6 and 36 ppb for aflatoxin levels 2 and 3, with degradation rates of 78% and 61%, respectively. The TNP produced higher aflatoxin degradation rates than the ENP. (C) 2003 Elsevier Science Ltd. All rights reserved.

Mendez-Albores, J. A., G. Arambula-Villa, et al. (2004). "Aflatoxins in pozol, a nixtamalized, maize-based food." International Journal of Food Microbiology 94(2): 211-215. ://000222374900009 To determine whether pozol, a nixtamalized maize-based food was contaminated with aflatoxins, samples of non-fermented pozol were collected during the period November 2002 to April 2003 from local markets at Comitan in Chiapas, Mexico. The samples were analyzed for the presence of aflatoxins. Nineteen out of one hundred and eleven samples were contaminated with aflatoxin B-2 (AFB(2)) and traces of aflatoxin B-1 (AFB(1)). The percentage of samples contaminated with AFB2 in pozol prepared with white maize was 5.4%. Pozol mixed with toasted cacao paste had a contamination rate of 41.5%. No aflatoxins were detected in pozol prepared with yellow maize. It was found that only I of 19 contaminated samples had aflatoxin concentrations above 20 ppb. (C) 2004 Elsevier B.V. All rights reserved.

Merrill, A. H., M. C. Sullards, et al. (2001). "Sphingolipid metabolism: Roles in signal transduction and disruption by fumonisins." Environmental Health Perspectives 109(Suppl. 2): 283-289. ://WOS:000168824500015 AND http://www.botanischergarten.ch/Bt/Merrill-Sphingolipid-Roles-2001.pdf Sphingolipids have important roles in membrane and lipoprotein structure and in cell regulation as second messengers for growth factors, differentiation factors, cytokines, and a growing list of agonists. Bioactive sphingolipids are formed both by the turnover of complex sphingolipids and as intermediates of sphingolipid biosynthesis. Usually, the amounts are highly regulated; however, by inhibiting ceramide synthase, fumonisins block the biosynthesis of complex sphingolipids and cause sphinganine land sometimes sphingosine) to accumulate. Where the mechanism has been studied most thoroughly, the accumulation of sphingoid bases is a primary cause of the toxicity of fumonisin B (FB). Nonetheless, the full effects of fumonisins probably involve many biochemical events. The elevations in sphingoid bases also affect the amounts of other lipids, including the l-phosphates and N-acetyl derivatives of sphinganine. Furthermore, the aminopentol backbone of FB1 (AP(1)) is both an inhibitor and a substrate for ceramide synthase, and the resultant N-palmitoyl-AP(1) (PAP(1)) is an even more potent inhibitor of ceramide synthase (presumably as a product analog). PAP(1) is 10 times more toxic than FB1 or API for HT-29 cells in culture, and hence may play a role in the toxicity of nixtamalized fumonisins. All these processes-the effects of fumonisins on sphingolipid metabolism, the pathways altered by perturbation of sphingolipid metabolism, and the complex cellular behaviors regulated by sphingolipids-must be borne in mind when evaluating the pathologic effects of fumonisins.

Meyers, D. M., G. Obrian, et al. (1998). "Characterization of aflJ, a gene required for conversion of pathway intermediates to aflatoxin." Applied and Environmental Microbiology 64(10): 3713-3717. ://000076295100024 The genes encoding the aflatoxin biosynthetic pathway enzymes have been localized as a cluster to a 75 kb DNA fragment. The enzymatic functions of the products of most of the genes in the cluster are known, but there are a few genes that have not yet been characterized. We report here the characterization of one of these genes, a gene designated aflJ. This gene resides in the cluster adjacent to the pathway regulatory gene, aflR, and the two genes are divergently transcribed. Disruption of aflJ in Aspergillus flavus results in a failure to produce aflatoxins and a failure to convert exogenously added pathway intermediates norsolorinic acid, sterigmatocystin, and O- methylsterigmatocystin to aflatoxin, The disrupted strain do es, however, accumulate pksA, nor-1, ver-1, and omtA transcripts under conditions conducive to aflatoxin biosynthesis, Therefore, disruption of aflJ does not affect transcription of these genes, and aflJ does not appear to have a regulatory function similar to that of aflR. Sequence analysis of aflJ and its putative peptide, AflJ, did not reveal any enzymatic domains or significant similarities to proteins of known function. The putative peptide does contain three regions predicted to be membrane-spanning domains and a microbodies C-terminal targeting signal.

Miller, J. D. (1995). "Fungi and Mycotoxins in Grain - Implications for Stored-Product Research." Journal of Stored Products Research 31(1): 1- 16. ://WOS:A1995QG57100002 This is an overview of the mycology and toxicology of the five agriculturally-important mycotoxins: deoxynivalenol, zearalenone, fumonisin, ochratoxin and aflatoxin. Consideration is given to the state of research with respect to the elimination of these toxins from human food and animal feed.

Miller, J. D. (2001). "Factors that affect the occurrence of fumonisin." Environmental Health Perspectives 109(2 supplement): 321-324. ://WOS:000168824500020 AND http://www.botanischergarten.ch/Bt/Miller-Factors-Fumonisin-2001.pdf The two important Fusarium ear rots of corn, Gibberella ear rot (Fusarium graminearum, formally F. moniliforme and allied species) and Fusarium ear rot (F. verticillioides and allied species) grow under different environmental conditions. F. graminearum grows well only between 26 and 28 degreesC and requires rain both at silking and during disease progression. F. verticillioides grows well at higher temperatures, and ear rot and fumonisin accumulation are associated with drought and insect stress and growing hybrids outside their areas of adaptation. In southern Transkei, where esophageal cancer has been associated with the consumption of F. verticillioides and funnonisin-contaminated corn, environmental conditions favor this fungus in most years. In the nearby areas where the soils, crops, food consumption, and populations are the same and where esophageal cancer is low, temperatures are cooler and F. graminearum is favored. Although F. verticillioides is associated with a disease of corn, it may be that this fungus is a mutualistic endophyte of the plant. Perhaps because of this, breeding for resistance to Fusarium ear rot has produced inconclusive results to date. The best available strategies for reducing the risk of fumonisin contents of maize are to ensure that hybrids are adapted to the environment and to limit drought stress and insect herbivory. It may also be necessary to make use of alternative strategies such as producing hybrids that contain enzymes to degrade fumonisin as it is produced.

Miller, J. D. (2002). Aspects of the ecology of Fusarium toxins in cereals. Mycotoxins and Food Safety. New York, KLUWER ACADEMIC / PLENUM PUBL. 504: 19-27. ://000175261000002 Species of the genus Fusarium account for three of the five agriculturally important mycotoxins which are deoxynivalenol, aflatoxin, fumonisin, zearalenone and ochratoxin. The toxigenic fusaria have been complicated to study because morphologically- similar strains represent different biologies: saprophytes, pathyotypes and endophytes. This might explain the difficulties with systems of taxonomy for Fusarium species and increasing reliance on molecular techniques to characterize taxa. Another remarkable feature of the toxigenic fusaria is that each species produces compounds that cross several species as well as families of compounds that are species specific. In addition, reproductively-isolated strains (from different continents) of important species such as F. graminearum produce different compounds, and even produce the same compounds by different biosynthetic pathways.

Miller, J. D. (2002). "Aspects of the ecology of Fusarium toxins in cereals." Mycotoxins and Food Safety 504: 19-27. ://WOS:000175261000002 Species of the genus Fusarium account for three of the five agriculturally important mycotoxins which are deoxynivalenol, aflatoxin, fumonisin, zearalenone and ochratoxin. The toxigenic fusaria have been complicated to study because morphologically-similar strains represent different biologies: saprophytes, pathyotypes and endophytes. This might explain the difficulties with systems of taxonomy for Fusarium species and increasing reliance on molecular techniques to characterize taxa. Another remarkable feature of the toxigenic fusaria is that each species produces compounds that cross several species as well as families of compounds that are species specific. In addition, reproductively-isolated strains (from different continents) of important species such as F. graminearum produce different compounds, and even produce the same compounds by different biosynthetic pathways.

Miller, J. D., M. E. Savard, et al. (1995). "Mycotoxin production by Fusarium moniliforme and Fusarium proliferatum from Ontario and occurrence of fumonisin in the 1993 corn crop." Canadian Journal of Plant Pathology-Revue Canadienne De Phytopathologie 17(3): 233-239. ://A1995TR40500006

Mirete, S., C. Vazquez, et al. (2004). "Differentiation of Fusarium verticillioides from banana fruits by IGS and EF-1 alpha sequence analyses." European Journal of Plant Pathology 110(5-6): 515-523. ://000222172600007 Fusarium verticillioides ( Gibberella moniliformis, G. fujikuroi mating population A) is an important pathogen of maize and produces several mycotoxins, including fumonisins, which cause diseases in humans and animals. The partial sequences of the IGS region ( Intergenic Spacer of rDNA units) and the translation elongation factor EF-1alpha gene of a representative sample ( 48 strains) of F. verticillioides isolated from diverse hosts, geographical origins and with different levels of fumonisin production were analyzed. A phylogenetic approach by PAUP was used to evaluate the genetic variability in this species and to detect the occurrence of lineages which could be associated with different hosts or produced different toxin profiles within this species. Genetic variability detected by both sequences was high, especially with the IGS sequence which showed a high number of parsimony- informative sites and nucleotide diversity. The results of the phylogenetic analysis indicated that F. verticillioides occurs as (i) a major fumonisin-producing population with a wide geographical distribution, wide host preferences ( cereals), showing variability and considerable incidence of sexual reproduction and (ii) a minor fumonisin non-producing population, with restricted host preference ( banana), low variability and clonal reproductive strategy.

Mislivec, P. B., M. W. Trucksess, et al. (1988). "Effect of Other Toxigenic Mold Species on Aflatoxin Production by Aspergillus-Flavus in Sterile Broth Shake Culture." Journal of Food Protection 51(6): 449-451. ://WOS:A1988N915700005

Missmer, S. A., L. Suarez, et al. (2006). "Exposure to fumonisins and the occurrence of neural tube defects along the Texas-Mexico border." Environmental Health Perspectives 114(2): 237-241. ://WOS:000235226300043 AND http://ehp.niehs.nih.gov/members/2005/8221/8221.pdf AND http://www.botanischergarten.ch/Bt/Missmer-Exposure-Fumonisins-2006.pdf

Monti, S. M., V. Fogliano, et al. (1999). "Polyclonal antibodies against fusaproliferin." Canadian Journal of Microbiology 45(1): 45-50. ://000080212200007 Fusaproliferin (FP), a toxic metabolite of the world-wide maize pathogens Fusarium proliferatum and Fusarium subglutinans, was recently found to be a natural contaminant of maize. Its toxic activity on haematopoietic human cell lines and its teratogenic effects on chicken embryos has been recently proved. Therefore a sensitive, rapid, and inexpensive screening test to detect FP in agricultural commodities is necessary to protect human health. FP-hemiglutarate conjugated to modified bovine serum albumin was synthesized, characterized, and used as an antigen for raising polyclonal antibodies by immunizing rabbits. Indirect and competitive ELISA and immunoblotting analyses were performed to determine antibody specificity towards the mycotoxin. The determination of 10 mu g of free FP/mL was achieved using antibodies purified by means of affinity chromatography on a FP-lysine-Sepharose column. This unsatisfactory detection limit is due to high background values; thus, this method is not competitive with traditional UV-HPLC methods.

Moore, K. G., M. S. Price, et al. (2004). "A chitinase from Tex6 maize kernels inhibits growth of Aspergillus flavus." Phytopathology 94(1): 82-87. ://000220532100008 The maize inbred Tex6 has resistance to colonization and aflatoxin accumulation by Aspergillus flavus. A protein inhibitory to growth of A. flavus has been identified from aqueous extracts of mature Tex6 seeds. This study reports the purification of a chitinase associated with this inhibitory activity to electrophoretic homogeneity and the further characterization of its properties. The inhibitory protein, which has an M-r of 29,000, as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, is an endochitinase that is also capable of exochitinase activity. The enzyme has an optimal pH of 5.5 and a temperature optimum of 45degreesC. Chitinase activity in maize kernels peaked approximately 36 days after pollination. The Tex6 chitinase purified in this study is capable of inhibiting the growth of A. flavus by 50% at a concentration of 20 mug/ml. Our data indicate that chitinase activity in Tex6 kernels makes a major contribution to the antifungal activity in this maize genotype. Partial peptide sequence of the chitinase showed it to differ from previously reported chitinases.

Moretti, A., G. Mule, et al. (2004). "Toxin profile, fertility and AFLP analysis of Fusarium verticillioides from banana fruits." European Journal of Plant Pathology 110(5-6): 601-609. ://000222172600015 Gibberella fujikuroi is composed of at least nine mating populations (MPs), corresponding to biological species and assigned letters ( from A to I). Each MP possesses a specific toxicological pro. le and a preferential host. Members of Fusarium verticillioides and F. thapsinum, anamorphs respectively of MPs A ( G. moniliformis) and F ( G. thapsina), share identical morphological traits, but they have a different preferential hosts ( maize and sorghum, respectively) and toxin profiles, being able the only member of MP A to produce fumonisins and the only member of MP F to produce moniliformin. Isolates from banana fruits were identified morphologically as F. verticillioides. The isolates were analyzed for fumonisin and moniliformin production. While none of the isolates produced fumonisin, all the isolates produced moniliformin. The isolates were crossed with tester strains of MPs A and F, showing ability to produce fertile perithecia only when crossed by MP A tester strains isolated from maize. However, the time required for the formation of fertile perithecia and their size differed significantly from the usual fertile crosses of strains belonging to MP A. Pathogenicity tests using such isolates of F. verticillioides isolated from banana and a set of F. verticillioides isolates isolated from maize were also performed on banana fruits. The data showed that the isolates from banana were more pathogenic. Finally, isolates from banana and maize were compared using AFLP. The results revealed that isolates from banana and maize produced two distinctly different clusters. In conclusion, isolates of F. verticillioides from banana showed specific traits ( toxin production, in vitro fertility, pathogenicity and molecular profiles), that were different to those of the same species from maize. This could reflect important differences in the ecology and natural history of the population from banana and should encourage further investigations into the mechanisms of toxin production and pathogenicity within the same MP.

Mphande, F. A., B. A. Siame, et al. (2004). "Fungi, aflatoxins, and cyclopiazonic acid associated with peanut retailing in Botswana." Journal of Food Protection 67(1): 96-102. ://000187939800015 Peanuts are important food commodities, but they are susceptible to fungal infestation and mycotoxin contamination. Raw peanuts were purchased from retail outlets in Botswana and examined for fungi and mycotoxin (aflatoxins and cyclopiazonic acid) contamination. Zygomycetes were the most common fungi isolated; they accounted for 41% of all the isolates and were found on 98% of the peanut samples. Among the Zygomycetes, Absidia corymbifera and Rhizopus stolonifer were the most common. Aspergillus spp. accounted for 35% of all the isolates, with Aspergillus niger being the most prevalent (20.4%). Aspergillus flavus/parasiticus were also present and accounted for 8.5% of all the isolates, with A. flavus accounting for the majority of the A. flavus/parasiticus identified. Of the 32 isolates of A. flavus screened for mycotoxin production, 11 did not produce detectable aflatoxins, 8 produced only aflatoxins B-1 and B-2, and 13 produced all four aflatoxins (B-1, B-2, G(1), and G(2)) in varying amounts. Only 6 of the A. flavus isolates produced cyclopiazonic acid at concentrations ranging from 1 to 55 mug/kg. The one A. parasiticus isolate screened also produced all the four aflatoxins (1,200 mug/kg) but did not produce cyclopiazonic acid. When the raw peanut samples (n = 120) were analyzed for total aflatoxins, 78% contained aflatoxins at concentrations ranging from 12 to 329 mug/kg. Many of the samples (49%) contained total aflatoxins at concentrations above the 20 mug/kg limit set by the World Health Organization. Only 21% (n = 83) of the samples contained cyclopiazonic acid with concentrations ranging from 1 to 10 mug/kg. The results show that mycotoxins and toxigenic, fungi are common contaminants of peanuts sold at retail in Botswana.

Munimbazi, C. and L. B. Bullerman (1996). "Molds and mycotoxins in foods from Burundi." Journal of Food Protection 59(8): 869-875. ://A1996VD34600014 Molds were isolated from various foods from Burundi and identified. The ability of these molds to produce aflatoxins, cyclopiazonic acid (CPA), and fumonisins, and the presence of these toxins in the foods were determined. Fusarium moniliforme was the predominant mold isolated from corn. It was also one of the dominant molds isolated from sorghum and sorghum meal. Very few molds were isolated from polished rice, millet, and millet meal. F. semitectum and F. equiseti were the most common molds isolated from haricot and mung beans. F. semitectum was also the predominant mold in peanuts. Peas (Pisum sativum) were predominantly contaminated with Aspergillus ochraceus and A. wentii. The predominant molds isolated from dried nonsalted Ndagala fish (Limnothrissa miodon and Stolothrissa tanganicae) were A. flavus, A. niger and A. sydowi. Dried crushed cassava (Manihot esculenta) tubers and cassava flour were predominantly contaminated with Penicillium citrinum, P. corylophilum, and P. chrysogenum. Very few molds were isolated from the infant food Musalac(TM). Thirty-seven of 95 isolates of A. flavus and all 5 isolates of A. parasiticus produced aflatoxins. Sixty-seven of the 95 isolates of A. flavus produced CPA, and all aflatoxin- producing A. flavus produced CPA. Ten of 20 isolates of A. oryzae and A. tamarii produced CPA. Fifty-one of 56 isolates of F. moniliforme and all 4 isolates of F. proliferatum produced fumonisins. High levels of fumonisin B-1 (12.2 to 75.2 mu g/g) were detected in all 6 samples of corn and 1 sample of sorghum meal. Neither aflatoxins nor CPA were found in any of the foods.

Munimbazi, C. and L. B. Bullerman (1998). "Inhibition of aflatoxin production of Aspergillus parasiticus NRRL 2999 by Bacillus pumilus." Mycopathologia 140(3): 163-169. ://000074958800008 Six isolates of Bacillus pumilus were tested for their ability to inhibit aflatoxin production of Aspergillus parasiticus NRRL 2999 in yeast extract sucrose (YES) broth. Aflatoxin production was inhibited in both simultaneous and deferred antagonism assays, suggesting that the inhibitory activity was due to extracellular metabolite(s) produced in cell-free supernatant fluids of cultured broth. The inhibition was not due to organic acids or hydrogen peroxide produced by B. pumilus since the inhibitory activity was not lost after pH adjustment or treatment of supernatant fluids with catalase. A range of media tested for the production of inhibitory metabolite(s) in supernatant fluids showed that all media supported bacterial growth and production of the metabolite(s). The metabolite(s) were produced over a wide range of temperature (25 to 37 degrees C) and pH (4 to 9) of growth of B. pumilus. They were stable over a wide range of pH (4 to 10) and were not inactivated after autoclaving at 121 degrees C for 30 minutes.

Munimbazi, C. and L. B. Bullerman (1998). "Isolation and partial characterization of antifungal metabolites of Bacillus pumilus." Journal of Applied Microbiology 84(6): 959-968. ://000075057100006 Antifungal metabolites produced by Bacillus pumilus in Potato Dextrose Broth (PDB) were isolated from culture supernatant fluid by precipitation with ammonium sulphate. The antifungal metabolites inhibited mycelial growth of many species of Aspergillus, Penicillium and Fusarium. They also inhibited production of aflatoxins, cyclopiazonic acid, ochratoxin A and patulin. The metabolites were heat-stable and remained active after sterilization at 121 degrees C for 15 min. Their activity was stable over a wide range of pH (2-10). The metabolites were resistant to hydrolysis by various proteases, peptidases and other enzymes. They were also resistant to denaturation by many protein-denaturing detergents except Nonidet P-40. The metabolites were soluble in water and relatively polar organic solvents. Chromatographic bioassay revealed that a crude precipitate of the metabolites contained only one compound with antifungal activity. The active compound did not form a fluorescent derivative with fluorescamine suggesting that the compound is either a cyclic polypeptide or a non-peptidic compound.

Munkvold, G. P. (2003). "Cultural and genetic approaches to managing mycotoxins in maize." Annual Review of Phytopathology 41: 99-116. ://000186493900006 AND http://www.botanischergarten.ch/Mycotoxins/Munkvold-Cultural-Mycotoxins-2003.pdf Infection of maize kernels by toxigenic fungi remains a challenging problem despite decades of research progress. Cultural practices, including crop rotation, tillage, planting date, and management of irrigation and fertilization, have limited effects on infection and subsequent mycotoxin accumulation. Current infrastructure and grain storage practices in developed countries can prevent postharvest development of mycotoxins, but this aspect remains a threat in developing countries, especially in tropical areas. Because most mycotoxin problems develop in the field, strategies are needed to prevent infection of growing plants by toxigenic fungi. Developing genetic resistance to Aspergillus flavus, Gibberella zeae, and Fusarium spp. (particularly F verticillioides) in maize is a high priority. Sources of resistance to each of these pathogens have been identified and have been incorporated into public and private breeding programs. However, few, if any, commercial cultivars have adequate levels of resistance. Efforts to control infection or mycotoxin development through conventional breeding and genetic engineering are reviewed. The role of transgenic insect control in the prevention of mycotoxins in maize is discussed.

Munkvold, G. P. (2003). "Epidemiology of Fusarium diseases and their mycotoxins in maize ears." European Journal of Plant Pathology 109(7): 705-713. ://000185661500006 Fusarium species cause two distinct diseases on ears of maize, Fusarium ear rot (or pink ear rot) and Gibberella ear rot (or red ear rot), both of which can result in mycotoxin contamination of maize grain. The primary causal agent for Fusarium ear rot is Fusarium verticillioides, but F. subglutinans and F. proliferatum are also important. Gibberella ear rot is caused primarily by F. graminearum, but F. culmorum can also be important, especially in Europe. Aspects of the epidemiology of both diseases have been studied for decades, but only recently have efforts been made to synthesize this information into comprehensive models of disease development. Much of the work on F. graminearum has focused on Fusarium head blight of small-grain crops, but some of the results obtained are also relevant to maize. The primary mycotoxins produced by these fungi, fumonisins and deoxynivalenol, have differing roles in the disease-cycle, and these roles are not completely understood, especially in the case of fumonisins. Progress is being made toward accurate models for risk assessment of both diseases, but key challenges remain in terms of integrating models of pre- and post-infection events, quantifying the roles of insects in these diseases, and characterizing interactions among competing fungi and the environment.

Munkvold, G. P. (2004). "Epidemiology of Fusarium diseases and their mycotoxins in maize ears." European Journal of Plant Pathology 109(7): 705-713. ://000185661500006 AND http://www.botanischergarten.ch/Mycotoxins/Munkvold-Epidemiology-Fusarium-2004.pdf Fusarium species cause two distinct diseases on ears of maize, Fusarium ear rot (or pink ear rot) and Gibberella ear rot (or red ear rot), both of which can result in mycotoxin contamination of maize grain. The primary causal agent for Fusarium ear rot is Fusarium verticillioides, but F. subglutinans and F. proliferatum are also important. Gibberella ear rot is caused primarily by F. graminearum, but F. culmorum can also be important, especially in Europe. Aspects of the epidemiology of both diseases have been studied for decades, but only recently have efforts been made to synthesize this information into comprehensive models of disease development. Much of the work on F. graminearum has focused on Fusarium head blight of small-grain crops, but some of the results obtained are also relevant to maize. The primary mycotoxins produced by these fungi, fumonisins and deoxynivalenol, have differing roles in the disease-cycle, and these roles are not completely understood, especially in the case of fumonisins. Progress is being made toward accurate models for risk assessment of both diseases, but key challenges remain in terms of integrating models of pre- and post-infection events, quantifying the roles of insects in these diseases, and characterizing interactions among competing fungi and the environment.

Munkvold, G. P. and W. M. Carlton (1997). "Influence of inoculation method on systemic Fusarium moniliforme infection of maize plants grown from infected seeds." Plant Disease 81(2): 211-216. ://A1997XN27800018 Two greenhouse and two field experiments were conducted in 1994 and 1995 to quantify the incidence of maize kernel infection resulting from systemic infection of maize plants by Fusarium moniliforme. Seeds were infected by two methods: (i) spray- inoculation of maize silks during seed development (field- infected), and (ii) soak-inoculation of mature seeds in a spore suspension (laboratory-infected). Plants were grown from infected seeds and assayed for systemic infection by the seed- inoculated strain, determined by vegetative compatibility of recovered isolates with the original strain. The seed- inoculated strain was recovered from stalks and kernels of plants grown from both types of infected seed. Mature plants grown from field-infected seeds had a higher percentage of their kernels infected with the seed-inoculated strain compared with plants from laboratory-infected seed. Mean incidence of infection by the seed-inoculated strain was 9.9 to 29.4% of all kernels (33.0 to 55.9% of F. moniliforme-infected kernels) in the plants grown from field-infected seed. Some plants from infected seed were subsequently silk-inoculated, and the silk- inoculated strain was recovered from a much higher percentage of kernels (26.5 to 37.5% of all kernels or 77.9 to 78.4% of F. maniliforme-infected kernels) than was the seed-inoculated strain; furthermore, silk inoculation significantly reduced incidence of kernel infection by the seed-inoculated strain. Seed infection by F. moniliforme resulted in systemic infection of plants and kernels. However, local infection (via silks) was a more important pathway to kernels than was systemic infection, and strains infecting the silks competed successfully against those entering the kernels through systemic development.

Munkvold, G. P. and A. E. Desjardins (1997). "Fumonisins in maize - Can we reduce their occurrence?" Plant Disease 81(6): 556-565. ://A1997XN28400001

Munkvold, G. P., R. L. Hellmich, et al. (1999). "Comparison of fumonisin concentrations in kernels of transgenic Bt maize hybrids and nontransgenic hybrids." Plant Disease 83(2): 130-138. ://000078234100007 and http://www.botanischergarten.ch/Mycotoxins/Munksvold-Comparison-Fumonisin.pdf Maize hybrids genetically engineered with genes from the bacterium Bacillus thuringiensis (Bt maize) express CryIA(b) and other Cry proteins that are toxic to certain insects, particularly the European corn borer (Ostrinia nubilalis). Maize kernel feeding by O. nubilalis often leads to infection by fungi in the genus Fusarium, including the fumonisin- producing species F. verticillioides and F. proliferatrum. In field experiments in 1995, 1996, and 1997, transgenic maize hybrids and near-isogenic, nontransgenic hybrids were manually infested with neonatal European corn borer larvae. Manual infestation increased Fusarium ear rot severity and fumonisin concentrations in kernels of nontransgenic hybrids. Transgenic hybrids with kernel expression of CryIA(b) consistently experienced less insect feeding on kernels and less Fusarium ear rot than their nontransgenic counterparts. In manually infested treatments, these hybrids also exhibited lower concentrations of fumonisins in kernels compared with their nontransgenic counterparts. In manually infested treatments in 1995, mean fumonisin B-1 concentrations were 8.8 mu g/g in the nontransgenic hybrid and 6.7 or 3.0 mu g/g in transgenic hybrids. In 1996, mean fumonisin B-1 concentrations in manually infested treatments were 4.9 mu g/g (range 2.3 to 8.8) for nontransgenic and 1.2 mu g/g (range 1.0 to 1.3) for transgenic hybrids with kernel expression. Mean total fumonisin concentrations (fumonisin B-1 + B-2 + B-3) were 7.0 mu g/g(range 3.0 to 12.2) for nontransgenic and 1.7 mu g/g (range 1.5 to 1.9) for transgenic hybrids with kernel expression. In 1997, mean fumonisin B-1 concentrations in manually infested treatments were 11.8 mu g/g (range 7.6 to 17.3) for nontransgenic and 1.3 mu g/g (range 0.8 to 2.2) for transgenic hybrids with kernel expression of CryIA(b) or Cry9C. Mean total fumonisin concentrations were 16.5 mu g/g (range 10.7 to 24.0) for nontransgenic and 2.1 mu g/g (range 1.5 to 3.1) for transgenic hybrids with kernel expression. Transgenic hybrids that do not express CryIA(b) or Cry9C in kernels did not consistently have fumonisin concentrations different from the nontransgenic hybrids. Higher fumonisin concentrations in nontransgenic hybrids were associated with high European corn borer populations during the early reproductive stages of the maize plants. These results indicate that under some conditions, genetic engineering of maize for insect resistance may enhance its safety for animal and human consumption.

Munkvold, G. P., R. L. Hellmich, et al. (1997). "Reduced Fusarium ear rot and symptomless infection in kernels of maize genetically engineered for European corn borer resistance." Phytopathology 87(10): 1071-1077. ://A1997XZ38000013 AND http://www.botanischergarten.ch/Bt/Munksvold-Reduced-Fusarium-1997.pdf Field experiments were conducted in 1994, 1995, and 1996 to evaluate the incidence and severity of Fusarium ear rot and the incidence of symptomless Fusarium infection in kernels of maize hybrids genetically engineered with Bacillus thuringiensis genes encoding for the delta-endotoxin CryIA(b). Treatments included manual infestation with European corn borer (ECB) larvae and insecticide applications to limit ECB activity to specific maize growth stages or mimic standard ECB control practices. Fusarium symptoms and infection were affected by the specific cryIA(b) transformation used in each hybrid that determines tissue-specific expression of CryIA(b). In hybrids expressing CryIA(b) in kernels, incidence and severity of Fusarium ear rot and incidence of symptomless kernel infection were reduced compared with near-isogenic hybrids lacking cryIA(b) genes. In plants that were manually infested with ECB, ear rot incidence was reduced by 87, 58, and 68%; severity was reduced by 96, 54, and 64%; and incidence of kernel infection by Fusarium species was reduced by 17, 38, and 38% in 1994, 1995, and 1996, respectively. Results were similar in treatments that were not manually infested, but differences between transgenic and nontransgenic hybrids were smaller. Most kernel infection was due to F. moniliforme, F. proliferatum, and F. subglutinans (section Liseola) collectively, and it was within this group that transgenic hybrids exhibited reduced infection. Expression of CryIA(b) in plant tissues other than kernels did not consistently affect Fusarium symptoms or infection. Disease incidence was positively correlated with ECB damage to kernels. Insecticide applications also reduced Fusarium symptoms and infection when applied to nontransgenic plants.

Munkvold, G. P., D. C. McGee, et al. (1997). "Importance of different pathways for maize kernel infection by Fusarium moniliforme." Phytopathology 87(2): 209-217. ://A1997XN26500014 The relative importance of several infection pathways (silks, stalks, and seed) leading to kernel infection of maize hybrids by Fusarium moniliforme was investigated in field experiments in 1993 and 1994. Systemic movement of specific fungal strains within plants was detected by using vegetative compatibility as a marker. Transmission of F. moniliforme from inoculated seed to stalks and developing kernels was detected in two of three field experiments; the seed-inoculated strain was detected in kernels on approximately 10% of ears. The percentage of kernels infected with the seed-inoculated strain ranged from 0 to 70%, with a mean of 0 to 2.5% (0 to 8.3% of F. moniliforme-infected kernels). Other pathways to kernel infection were more effective than seed transmission and systemic infection. F. moniliforme strains inoculated into the crowns and stalks of plants were found throughout the stalks and in up to 95% of the kernels in individual plants. Infection through the silks was clearly the most effective pathway to kernel infection. This was the only inoculation method that significantly increased overall incidence of F. moniliforme infection in kernels; the silk-inoculated strain infected up to 100% of the kernels in individual ears, with a treatment mean as high as 83.7% of kernels. When plants were silk-inoculated the percentage of kernels infected by other F. moniliforme strains from the seed or stalk was reduced, apparently due to competition among strains. This study provides evidence that systemic development of F. moniliforme from maize seed and stalk infections can contribute to kernel infection, but silk infection is a more important pathway for this fungus to reach the kernels.

Nadubinska, M., A. Ritieni, et al. (2003). "Chlorophyll content in maize plants after treatment with fusariotoxins." Biologia 58(1): 115-119. ://000181545100017 The aim of this study was to prove the effect of fusariotoxins on maize plants. Two-week-old plants of two cultivars with different susceptibility to Fusarium infection were used to study chlorophyll a, b contents after toxins treatment. Moniliformin (MF), fumonisin B-1 (FB1), fusaproliferin (FP), zearalenone (ZEN) and deoxynivalenol (DON) were added to root medium of intact plants at concentration 30 mug mL(-1), or directly to chlorophyll extracts at concentration 20 mug mL(- 1). The greatest decrease in chlorophyll content in vivo caused ZEN and FP in both tested cultivars and DON only in the susceptible one. On the other hand the treatments with FB1 and in susceptible cultivar also with MF have led to increase in chlorophyll content. Depending on toxin, there were slight differences between the cultivars. When toxins were added directly to the chlorophyll extracts, the greatest decrease in chlorophyll a content was induced by MF, followed by FB1 and FP. After treatment with DON and ZEN chlorophyll content reduction did not rearch the level in controls. Recently isolated FP in vitro acted similarly as toxins with the well known phytotoxic properties (MF, FB1) and in vivo as DON and ZEN.

Naidoo, G., A. M. Forbes, et al. (2002). "Resistance to aspergillus ear rot and aflatoxin accumulation in maize F-1 hybrids." Crop Science 42(2): 360-364. ://000174093500007 Unacceptable levels of contamination by aflatoxin, a carcinogenic toxin, produced by Aspergillus flavas Link:Fr can halt the sale and shipment of maize (Zea mavs L.) grain. Our objectives were to: (i) determine the relative resistance to A. flavus and aflatoxin accumulation in F-1 hybrids produced by crossing promising resistant maize inbreds. regardless of heterotic pattern; (ii) investigate the genetic basis of resistance for this subset of inbreds through diallel analysis, and (iii) determine which inbreds are the most promising sources of resistance for molecular marker mapping and breeding programs. Two historically important inbreds and six inbreds tentatively associated with reduced ear rot and inhibition of aflatoxin production were crossed in A combinations. The resulting F-1 hybrids were evaluated for two years. Ears were inoculated 20 to 24 d after midsilk by a pinboard method and a mixture of coniclia of Aspergillus flarus Link:Fr. isolates. Individual ears from each plot were rated by scoring the percent visible rot in the inoculated area. Anatoxin B, levels in harvested ears were determined by an indirect competitive ELISA. The highest level of resistance for car rot and aflatoxin accumulation "as detected for resistant inbred x resistant inbred F-1 hybrids, but they were not significantly different from many resistant inbred x historically important inbred F-1 hybrids. Diallel analysis indicated general combining ability (GCA) effects for ear rot and aflatoxm levels were highly significant among hybrids overall, and for the inbreds Tex6 and Oh516. The results indicate that Tex6 and Oh516 are promiqing resistance sources for molecular marker mapping and breeding programs in diverse genetic backgrounds.

Nayak, S., R. B. Sashidhar, et al. (2001). "Quantification and validation of enzyme immunoassay for urinary aflatoxin B-1-N-7-guanine adduct for biological monitoring of aflatoxins." Analyst 126(2): 179-183. ://000166816300011 The aflatoxin B-1-N-7-guanine (AFB(1)-N-7-guanine) adduct has been established as one of the relevant biomarkers of dietary aflatoxin (AFB(1)) exposure. Measurement of this adduct is potentially a useful dosimeter in molecular epidemiological studies. This paper reports the application and evaluation of a sensitive indirect competitive enzyme-linked immunosorbent assay (ELISA) for the detection and quantification of urinary AFB(1)-N-7-guanine adduct in high risk populations exposed to dietary aflatoxin. Earlier, we had reported a simple and rapid indirect ELISA method for AFB(1)-N-7-guanine adduct in the urine and liver tissues using polyclonal antibodies specific to AFB(1)-N-7-guanine adduct. The method was evaluated using a rodent model (Fischer 344), exposed to 1 mg kg(-1) body mass of AFB(1) and human urine samples obtained from a maize eating population, environmentally exposed to AFB(1) through their diet. The levels of AFB(1)-N-7-guanine adduct in rat and human urine ranged from 6.42 to 20.16 mug mg(-1) creatinine and from 9.30 to 13.43 ng mg(-1) creatinine, respectively. The level of AFB(1) in the diet as estimated by ELISA ranged from 1000 to 3600 ng d(-1). The interesting observation in these studies is that the females (in both rodents and human subjects) are more efficient than males at excreting the adduct. Total adduct (DNA bound adduct and guanine adduct excreted in urine) was found to be similar in male and female rats. However, 63% of the total adduct was accounted for in urine of female rats, whereas male rats excreted 47% of the total adduct in their urine. The present method may find wide application as a biochemical tool in molecular epidemiological studies with respect to human exposure to dietary aflatoxins.

Nelson, P. E., R. D. Plattner, et al. (1992). "Fumonisin-B1 Production by Fusarium Species Other Than F- Moniliforme in Section Liseola and by Some Related Species." Applied and Environmental Microbiology 58(3): 984-989. ://A1992HH28400033 Strains of Fusarium proliferatum, F. subglutinans, F. anthophilum, F. annulatum, F. succisae, F. beomiforme, F. dlamini, F. napiforme, and F. nygamai from a variety of substrates and geographic areas were tested for the production of fumonisin B1 in culture. None of the cultures of F. subglutinans (0 of 23), F. annulatum (0 of 1), F. succisae (0 of 2), or F. beomiforme (0 of 15) produced fumonisin B1 in culture. Strains of F. proliferatum (19 of 31; 61%) produced fumonisin B1 in amounts ranging from 155 to 2,936 ppm, strains of F. anthophilum (3 of 17; 18%) produced fumonisin B1 in amounts ranging from 58 to 613 ppm, strains of F. dlamini (5 of 9; 56%) produced fumonisin B1 in amounts ranging from 42 to 82 ppm, strains of F. napiforme (5 of 33; 15%) produced fumonisin B1 in amounts ranging from 16 to 479 ppm, and strains of F. nygamai (10 of 27; 37%) produced fumonisin B1 in amounts ranging from 17 to 7,162 ppm. Of the species tested, F. proliferatum is the most important producer of fumonisin B1 because of its association with corn and animal mycotoxicoses such as porcine pulmonary edema. F. napiforme and F. nygamai also may be important because of their association with the food grains millet and sorghum. At present, F. anthophilum and F. dlamini are of minor importance because they are not associated with corn or other major food grains and have only a limited geographic range. This is the first report of the production of fumonisins by F. anthophilum, F. dlamini, and F. napiforme.

Nesci, A. and M. Etcheverry (2002). "Aspergillus section Flavi populations from field maize in Argentina." Letters in Applied Microbiology 34(5): 343-348. ://000175732300006 Aims: Populations of Aspergillus section Flavi were studied from a commercial field of maize in Rio Cuarto, Cordoba, Argentina. Methods and Results: The Aspergillus species were isolated from soil, debris and insects during three periods: pre-planting, growing maize and post-harvest. The colony count from non-rhizospheric soil in the pre-planting period was higher than in growing maize and the post-harvest period. Debris samples analysed during all periods showed similar infection percentages for Aspergillus section Flavi. The samples of insects collected during the maize-growing period showed a lower percentage of Aspergillus isolates than the samples from soil and debris. Aflatoxigenic strains were present in lower levels in each component of the agroecosystem studied. All the strains that produced sclerotia were L strains. Conclusions: In this field agroecosystem, the only strains with a high probability for transfer to the storage agroecosystem were L strains with low toxigenic potential. Significance and Impact of the Study: Maize pre- harvest contamination with aflatoxigenic inoculum was not significant.

Nesci, A., M. Etcheverry, et al. (2004). "Osmotic and matric potential effects on growth, sugar alcohol and sugar accumulation by Aspergillus section Flavi strains from Argentina." Journal of Applied Microbiology 96(5): 965-972. ://000221329000008 Aims: The effect of osmotic and matric potential stress on growth and sugar alcohols (polyols: glycerol, erythritol, arabitol and mannitol) and sugars (trehalose and glucose) accumulation in toxigenic and nontoxigenic colonies of Aspergillus flavus and A. parasiticus was evaluated. Methods and Results: Growth of Aspergillus section Flavi with significant reductions at 20 and 30degreesC was more sensitive to changes in matric potential, between 60 and 100% in the range of -7 to -14 MPa. No significant differences were found between toxigenic and nontoxigenic strains for both species. Total polyol accumulation in unamended maize meal agar medium (-0.75 MPa water potential) was higher at 30 than 20degreesC. The major change in concentrations of endogenous sugars and total polyols was in matrically amended medium (with PEG 8000) at -7 and -10 MPa. Accumulation of glucose, arabitol, mannitol and erythritol content of A. flavus and A. parasiticus mycelial colonies was greater in normal unstressed maize meal agar medium (- 0.75 Mpa) at 20degreesC. This was modified by solute and matric stress. Conclusions: The data showed relative sensitivity to osmotic and matric potential, and temperature, and the impact on growth rates, polyol and sugar accumulation in mycelia of A. flavus and A. parasiticus. Significance and Impact of the Study: The matric potential effects on growth may be of particular importance for growth and survival in environments with low-matric potential stress. The tolerance of spoilage fungi such as Aspergillus section Flavi to such modifications could increase the potential for spoilage and mycotoxin production in such substrates. This knowledge is important for understanding the relative ecological fitness of these aflatoxigenic species and in the development of prevention strategies for their control.

Nesci, A., M. Rodriguez, et al. (2003). "Control of Aspergillus growth and aflatoxin production using antioxidants at different conditions of water activity and pH." Journal of Applied Microbiology 95(2): 279-287. ://000184110900010 Aims: The effect of butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), trihydroxybutyrophenone (THB) and propyl paraben (PP) (at concentrations of 1, 10 and 20 mmol l(-1)) on germination, growth and aflatoxin B-1 production by Aspergillus section Flavi was evaluated. Methods and Results: Studies on the percentage of spore germination, elongation rate, growth rate and aflatoxin B-1 production were carried out in vitro in relation to water activity (a (w)) at 0.982, 0.937, 0.809 and 0.747 values. At 0.809 and 0.747a (w) values none of the isolates was able to germinate. Overall, PP and BHA were the antioxidants most effective at inhibiting germination of both species. In the presence of the lowest concentration of BHA and PP (1 mmol l(-1)) the conidial germination percentage ranged from 2 to 19% after 15 h of incubation at the highest water activity tested. BHA and PP at 10-20 mmol l(-1) completely inhibited conidial germination. The antioxidants more efficient in controlling Aspergillus elongation rate were PP, BHT and BHA. All strains were much more sensitive to all antioxidants tested on the percentage of spore germination and growth rate at 0.937a (w). The antioxidants PP and BHA completely inhibited aflatoxin B-1 production by all strains when added at 1 mmol l(-1). Decreased aflatoxin B-1 levels in comparison with the control, were observed with BHT at 1, 10 and 20 mmol(-1) with the strain T20 at 0.982a (w). In contrast, stimulation was observed with the antioxidant THB at 10 and 20 mmol l(-1) at 0.937a (w) with the strains T20 and T23. The effect of BHA and PP at 1 mmol l(-1) on lag phase and growth rate was maintained in the pH range between 6 and 8. At all pH values the inhibitory effect of BHA was higher than PP. No aflatoxin B-1 was detected at all pH values. Conclusions: The data show that BHA and PP could be considered as effective fungitoxicants for A. flavus and A. parasiticus. Significance and Impact of the Study: The information obtained show promise for controlling growth and aflatoxin B-1 in stored maize. Futher studies should be carried out to examine the potential for antioxidants, such as BHA and PP to effectively control both growth and aflatoxin production.

Ngoko, Z., W. F. O. Marasas, et al. (2001). "Fungal infection and mycotoxin contamination of maize in the Humid Forest and the Western Highlands of Cameroon." Phytoparasitica 29(4): 352-360. ://000170618600007 Fungal incidence and mycotoxin contamination of farm-stored maize were assessed and compared in grain samples from three villages each in two agroecological zones over time. Maize samples were collected at 2 and 4 months after stocking from 72 farmers' stores in 1996 and 1997 in the Humid Forest (HF) and Western Highlands (WHL) of Cameroon. Mycological assays of these samples revealed several fungal species. Nigrospora spp. were the most prevalent fungi in HF (32%) and WHL (30%) in 1996, Fusarium verticillioides (22%) and F. graminearum (27%) were also isolated from these samples. In the WHL in 1996, no significant difference in fungal incidence was found among villages for samples collected 2 months after harvest, but at 4 months incidence was significantly higher (P<0.05). In 1997 the levels of fungal contamination were lower than in 1996. The incidence of Aspergillus spp. was low in general, ranging from 0.0 to 5.9% infected kernels. Analysis with thin layer chromatography detected low levels of aflatoxins in a few samples. f. verticillioides mycotoxin fumonisin B-1 (300-26,000 ng/g) and F graminearum metabolites deoxynivalenol (<100-1,300 ng/g) and zearalenone (<50-110 ng/g) were determined by means of polyclonal antibody competitive direct enzyme-linked immunosorbent assay. A significant correlation (r=0.72; P=0.0001) was found between the incidence of F graminearum and the contamination with deoxynivalenol. Storage time (2 vs 4 months after stocking) had a significant positive effect (r=0.39; P=0.013) on the level of fumonisin B-1. This is the first report of the natural occurrence of these mycotoxins in maize in Cameroon.

Obrian, G. R., A. M. Fakhoury, et al. (2003). "Identification of genes differentially expressed during aflatoxin biosynthesis in Aspergillus flavus and Aspergillus parasiticus." Fungal Genetics and Biology 39(2): 118-127. ://000183523800002 A complex regulatory network governs the biosynthesis of aflatoxin. While several genes involved in aflatoxin production are known, their action alone cannot account for its regulation. Arrays of clones from an Aspergillus flavus cDNA library and glass slide microarrays of ESTs were screened to identify additional genes. An initial screen of the cDNA clone arrays lead to the identification of 753 unique ESTs. Many showed sequence similarity to known metabolic and regulatory genes; however, no function could be ascribed to over 50% of the ESTs. Gene expression analysis of Aspergillus parasiticus grown under conditions conducive and non- conductive for aflatoxin production was evaluated using glass slide microarrays containing the 753 ESTs. Twenty-four genes were more highly expressed during aflatoxin biosynthesis and 18 genes were more highly expressed prior to aflatoxin biosynthesis. No predicted function could be ascribed to 18 of the 24 genes whose elevated expression was associated with aflatoxin biosynthesis. (C) 2003 Elsevier Science (USA). All rights reserved.

Odhav, B. and V. Naicker (2002). "Mycotoxins in South African traditionally brewed beers." Food Additives and Contaminants 19(1): 55-61. ://000173206000008 Traditionally brewed alcoholic beverages are regularly consumed by most ethnic black South Africans. Maize and barley, both of which are used for producing locally brewed alcoholic beer, are frequently contaminated by mycotoxin-producing moulds. The study was undertaken to investigate whether these toxins are present in raw grains and the traditional beers imbibed by the local black African population. It was established that the raw ingredients (sorghum, sorghum malt grains, maize grits), commercially produced traditional beers (Utshwala and Utshwala special) and home-brewed beers (Umqombotha, Isiqatha, Imfulamfula) were contaminated by bacteria and fungi (both yeasts and moulds). The contaminating moulds were isolated and identified. The contaminated samples were analysed for aflatoxins B-1, B-2, G(1) and G(2), zearalenone, citrinin, deoxynivalenol, and ochratoxin A using a multi-mycotoxin thin- layer chromatography screening method and the toxins were quantified by high-performance liquid chromatography. Grain samples were infected by Aspergillus flavus, A. alliaceus, A. clavatus, Penicillium spp., Rhizopus spp. and Mucor spp. Sorghum malt grain samples contained the toxin zearalenone. No mycotoxin-producing fungi were present in the fermented beers but two of six commercial beer samples contained aflatoxins (200 and 400 mug l(-1)) and 45% (13 of 29) of the home-brewed beers had zearalenone (range 2.6-426 mug l(-1)) and/or ochratoxin A (3-2340 mug l(-1)).

Odvody, G. and C. F. Chilcutt (2006). Aflatoxin and Insect Response of Conventional Non-Bt, MON810 (Cry1Ab) and MON 89034 (CryA, 105- Cry2Ab2) Corn Hybrids in South Texas, Poster. http://www.botanischergarten.ch/Bt/Odvody-Aflatoxin-Texas-Poster-2006.pdf

Odvody, G. N. and C. F. Chilcutt (2002). "Aflatoxin and insect response in South Texas of near-isogenic corn hybrids with Cry1Ab and Cry2Ab events." Mycopathologia 155(1-2): 107. ://BIOSIS:PREV200300181899

Ono, E. Y. S., M. A. Ono, et al. (2001). "Evaluation of fumonisin-aflatoxin co-occurrence in Brazilian corn hybrids by ELISA." Food Additives and Contaminants 18(8): 719-729. ://000170014200004 The natural co-occurrence of fumonisins and aflatoxins was investigated in freshly harvested corn kernels (150 samples, 62 hybrids), acquired from the Central-Southern (27 samples, 21 hybrids), Central-Western (86 samples, 51 hybrids) and Northern (37 samples, 18 hybrids) regions of the State of Parana, Brazil using enzyme-linked immunosorbent assay (ELISA). Fumonisins were detected in 147 (98%) samples at a concentration range of 0.096 to 22.6 mug/g, while aflatoxins were detected in 17 (11.3%). All the aflatoxin- positive samples (range 38.0-460.0 ng/g) came from the Central-Western region and were co- contaminated with fumonisins. Fumonisin contamination was higher in corn from the Northern (9.85 mug/g) and Central- Western regions (5.08 mug/g), when compared with the Central- Southern region (1.14 mug/g). The overall evaluation detected 62% samples with fumonisin levels less than or equal to5.0 mug/g. Regional differences affected fumonisin levels in the same hybrid, regardless of Fusarium count and moisture content, suggesting interference from climatic conditions, in addition to the local predominance of toxigenic strains of the Fusarium biotype.

Ono, E. Y. S., E. Y. Sasaki, et al. (2002). "Post-harvest storage of corn: effect of beginning moisture content on mycoflora and fumonisin contamination." Food Additives and Contaminants 19(11): 1081-1090. ://000179163600011 The effect of storage on mycoflora profile was monitored bimonthly in 36 corn (Zea mays L.) samples, dividing the same sample into groups dried to 11 and 14% moisture content (1008 analysis). These groups were further subdivided based on the initial total count (moulds and yeasts) up to 10(4) CFU g(-1) (12 samples, range 1.6 x 10(4) to 9.0 x 10(4), mean 3.8 x 10(4) CFU g(-1)) and up to 10(5) CFU g(-1) (24 samples, range 1.0 x 10(5) to 5.0 x 10(5), mean 2.7 x 10(5) CFU g(-1)). In the corn group dried to 11%, the fumonisin content was analysed at the initial stage (freshly harvested) and at the end of 12-month storage. Fusarium spp. and Penicillium spp. prevailed at the freshly harvested stage (100%), maintaining this profile throughout 12 months, in corn dried to both 11 and 14%. Cladosporium spp., Aspergillus spp. and Phoma spp. were also detected at lower frequencies during the storage. Fusarium spp. and the total fungal colony count during 12-month storage carried out with samples dried to 11 or 14% moisture content were statistically evaluated using ANOVA for randomized complete block design. The correlation between storage time and Fusarium spp. and total fungal colony count data was analysed by Pearson's correlation test. There was no difference in Fusarium spp. and total counts in the 10(4) CFU g(-1) initial total count group throughout the storage time (p < 0.05). There was a negative correlation between fungal population and storage time (p < 0.05) in the 10(5) CFU g(-1) initial total count group. Fumonisins were detected in all freshly harvested corn, at a mean concentration of 9.9+/-6.0 mug g(-1) (range 0.74-22.6 mug g(-1)). These values did not change in the 12- month stored corn (mean of 9.9+/-5.8 mug g(-1), range 0.81-23.7 mug g(-1)). These post-harvest data indicated the importance of moisture content at the crop harvesting/predrying stage to control fungal growth and further fumonisin production.

Oren, L., S. Ezrati, et al. (2003). "Early events in the Fusarium verticillioides-maize interaction characterized by using a green fluorescent protein-expressing transgenic isolate." Applied and Environmental Microbiology 69(3): 1695-1701. ://000181435600048 The infection of maize by Fusarium verticillioides can result in highly variable disease symptoms ranging from asymptomatic plants to severe rotting and wilting. We produced F. verticillioides green fluorescent protein-expressing transgenic isolates and used them to characterize early events in the F. verticillioides-maize interaction that may affect later symptom appearance. Plants grown in F. verticillioides-infested soil were smaller and chlorotic. The fungus colonized all of the underground parts of a plant but was found primarily in lateral roots and mesocotyl tissue. In some mesocotyl cells, conidia were produced within 14 to 21 days after infection. Intercellular mycelium was detected, but additional cells were not infected until 21 days after planting. At 25 to 30 days after planting, the mesocotyl and main roots were heavily infected, and rotting developed in these tissues. Other tissues, including the adventitious roots and the stem, appeared to be healthy and contained only a small number of hyphae. These results imply that asymptomatic systemic infection is characterized by a mode of fungal development that includes infection of certain tissues, intercellular growth of a limited number of fungal hyphae, and reproduction of the fungus in a few cells without invasion of other cells. Development of visibly rotted tissue is associated with massive production of fungal mycelium and much less organized growth.

Orsi, R. B., B. Correa, et al. (2000). "Mycoflora and occurrence of fumonisins in freshly harvested and stored hybrid maize." Journal of Stored Products Research 36(1): 75-87. ://000084769200008 The study of the mycoflora in stored grain permits an evaluation of cereal storage conditions that affect grain deterioration and the risk of mycotoxin contamination, Abiotic factors can directly affect the relative frequency of fungal populations in stored grain. The aim of the present work was to study the influence of abiotic factors on variations of mycoflora of freshly harvested and stored maize in Brazil and the occurrence of fumonisins. Samples (195) of three hybrids of maize were analyzed monthly during one year. Microbiological analysis revealed a predominance of Fusarium spp, which presented the greatest total number of colony forming units per gram in the three hybrids, namely: Br 201 (11 x 10(4) to 5340 x 10(4) CFU/g), C 125 (18 x 10(4) to 2790 x 10(4) CFU/g) and Cx 322 (25 x 10(4) to 2940 x 10(4) CFU/g), followed by Penicillium spp, Aspergillus spp and 10 other fungal genera. Fusarium moniliforme Sheldon was the most prevalent species (59.2% of Fusarium isolates in Br 201, 55.4% in C 125 and 69.2% in Cx 322). Fusarium spp showed significant negative correlations with mean temperature and relative humidity of the air. Higher temperatures and relative humidity at the end of the study and high moisture content at the beginning of the study were observed. The CFU/g values recorded for the three predominant genera exceeded the internationally accepted tolerance limits. The mycotoxicological evaluation indicated contamination of 176 samples (90.2%) with fumonisin B-1 and of 190 samples (97.4%) with fumonisin B-2. (C) 2000 Elsevier Science Ltd. All rights reserved.

Oswald, I. P., C. Desautels, et al. (2003). "Mycotoxin fumonisin B-1 increases intestinal colonization by pathogenic Escherichia coli in pigs." Applied and Environmental Microbiology 69(10): 5870-5874. ://000185881300018 Fumonisin B-1 (FB1) is a mycotoxin that commonly occurs in maize. FB1 causes a variety of toxic effects in different animal species and has been implicated as a contributing factor of esophageal cancers in humans. In the present study, we examined the effect of dietary exposure to FB1 on intestinal colonization by pathogenic Escherichia coli associated with extraintestinal infection. Three- week-old weaned pigs were given FB1 by gavage as a crude extract or as a purified toxin at a dose of 0.5 mg/kg of body weight daily for 6 days. On the last day of the toxin treatment, the pigs were orally inoculated with an extraintestinal pathogenic E. coli strain. All animals were euthanized 24 h later, necropsies were performed, and tissues were taken for bacterial counts and light microscopic examination. Ingestion of FB1 had only a minimal effect on animal weight gain, did not cause any macroscopic or microscopic lesions, and did not change the plasma biochemical profile. However, colonization of the small and large intestines by an extraintestinal pathogenic E. coli strain was significantly increased. Our results show that FB1 is a predisposing factor to infectious disease and that the pig can be used as a model for the study of the consequences of ingesting mycotoxin-contaminated food.

Otsuki, T., J. S. Wilson, et al. (2001). "Saving two in a billion: quantifying the trade effect of European food safety standards on African exports." Food Policy 26(5): 495-514. ://000171758800003 and http://www.botanischergarten.ch/Mycotoxins/Otsuki-Saving-Food-Policy.pdf A growing concern over health risks associated with food products has prompted close examination of sanitary and phytosanitary standards in industrialized countries. This paper quantifies the impact of a new harmonized aflatoxin standard set by the EU on food exports from Africa. We employ a gravity model to estimate the impact of changes in differing levels of protection based on the EU standard, in contrast to those suggested by international standards. The analysis is based on trade and regulatory survey data for 15 European countries and nine African countries between 1989 and 1998. Our results suggest that the implementation of the new aflatoxin standard in the EU will have a negative impact on African exports of cereals, dried fruits and nuts to Europe. The new EU standard, which would reduce health risk by approximately 1.4 deaths per billion a year, will decrease these African exports by 64% or US$ 670 million, in contrast to regulation set through an international standard. (C) 2001 Elsevier Science Ltd. All rights reserved.

Oyebanji, A. O. and B. J. O. Efiuvwevwere (1999). "Growth of spoilage mould and aflatoxin B-1 production in naturally contaminated or artificially inoculated maize as influenced by moisture content under ambient tropical condition." International Biodeterioration & Biodegradation 44(4): 209-217. ://000086173600004 Maize (cu. TSZB) samples were re-moistened to different moisture contents (m.c.s) of 13, 15, 17, 20, 25, 30 or 35% and stored with the natural microflora or sterilized before artificial inoculation with either single or mixed moulds (Aspergillus flavus, A. niger., Penicilium purpurogenum and Fusmarium moniliforme) and evaluated for initiation time for moulding, fungal populations and aflatoxin B-1 production. Whereas the fungal populations of naturally contaminated maize of 13% m.c, decreased significantly with storage, 17 and 20% m.c. maize increased with the latter showing maximum of about log(10) 7 colony forming units (cfu g(-1)). Of the samples (13, 15, 17 or 20% m.c. maize), only those of greater than or equal to 20% m.c. showed hazardous levels (> 20 ppb) of aflatoxin B-1 production. The 20% b m.c, sample also showed a significant positive correlation (r = 0.92) between m.c. and fungal load but those of lower m.c.s exhibited poor correlations, probably reflecting the absence of changes in the m.c.s of the 13, 15 and 17% m.c. maize. Aflatoxin BI content of 25% m.c. maize increased with increase in inoculum concentration of A. flavus Mixed mould inoculation of maize samples resulted in a reduction in aflatoxin concentration with co-cultures of A. flavus and P. purpurogenum showing the lowest production, while that inoculated with A. flavus alone (control) exhibiting the maximum production. Initiation time for moulding was most rapid in greater than or equal to 20% m.c, maize irrespective of inoculum type, with A. flavus being the most invasive in singly inoculated samples. However, A flavus was most competitive in 20-30% m.c. maize inoculated with mixed moulds, while F. moniliforme was most competitive in the 35%, b m.c. maize. (C) 2000 Published by Elsevier Science Ltd. All rights reserved.

Pacin, A. M., H. H. L. Gonzalez, et al. (2002). "Fungi associated with food and feed commodities from Ecuador." Mycopathologia 156(2): 87-92. ://000181762700008 Freshly harvested soybean, rice and corn from farms and corn- based pelleted feeds were collected from ranches from the coastal and mountain regions in Ecuador during 1998, and assessed for fungal contamination. The most prevalent fungi on pelleted feed were Aspergillus flavus and Fusarium graminearum. The prevalent fungi recovered from soybean were F. verticillioides, F. semitectum, Aspergillus flavus and A. ochraceus. In rice, F. oxysporum was the most prevalent toxigenic fungal species recorded, followed by F. verticillioides and A. flavus. In corn, F. verticillioides was the most prevalent fungus isolated in both the coastal and mountain regions, with high isolation frequencies of A. flavus and A. parasiticus at the coast. Based on the toxigenic species recovered, ochratoxin A may pose a contamination risk for soybean. A higher probability of aflatoxin contamination of corn was found in the coastal samples compared to those of the mountain region, while a risk of fumonisin contamination of corn exists in both regions.

Palencia, E., O. Torres, et al. (2003). "Total fumonisins are reduced in tortillas using the traditional nixtamalization method of mayan communities." Journal of Nutrition 133(10): 3200-3203. ://000185711400033 Fumonisin B-1 (FB1) is a maize mycotoxin. In tortilla preparation, maize is treated with lime (nixtamalization), producing hydrolyzed FB1 (HFB1) due to loss of the tricarballylic acid side chains. This study determined the following: 1) whether nixtamalization by Mayan communities reduces total fumonisins, and 2) the steps in the process at which reduction occurs. Tortillas prepared by the traditional process contained FB1, FB2 and FB3 and their hydrolyzed counterparts. There were equimolar amounts of FB1 and HFB1 in the tortillas, but the total fumonisins were reduced 50%. The total FB1 plus HFB1 in the residual lime water and water washes of the nixtamal accounted for 50% of the total FB1 in the uncooked maize. HFB1 and FB1 were present in a 1:1 mol/L ratio in the water washes of the nixtamal, the masa dough and the cooked tortillas, whereas the ratio of HFB1:FB1 in lime water after steeping was 21. Water washes contained 11% of the FB1 that was in the uncooked maize. The results show that the traditional method reduced the total fumonisins in tortillas and reduced the sphinganine elevation (a biomarker closely correlated with fumonisin toxicity) in cells treated with extracts of tortillas compared with cells treated with extracts of contaminated maize.

Papp, E., K. H-Otta, et al. (2002). "Liquid chromatographic determination of aflatoxins." Microchemical Journal 73(1-2): 39-46. ://000178685700007 The difurancoumarin derivatives known as aflatoxins are highly toxic fungi metabolites belonging to the vast class of mycotoxins, which can contaminate foods and feeds when storage conditions favor fungal growth. Because of potential health hazards for humans, levels of aflatoxins are monitored throughout the world. During the past two decades several chromatographic and other methods were developed for identification and determination of aflatoxins in agricultural and food products. This paper is a review of the overpressured- layer chromatographic (OPLC) and high performance liquid chromatographic methods most often used for the analysis of aflatoxins. However, emphasis is placed on summarizing the OPLC methods developed for determination of aflatoxins in maize, wheat, fish meat, peanut samples, rice and sunflower seeds spiked with aflatoxins B-1, B-2, G(1) and G(2) in concentration of 2-10 mug/cm(3), which were developed in our laboratory. The results of the proposed validation procedure, whose development was based on the guideline of the International Conference on Harmonization (ICH) for pharmaceutical products (1994, Brussels), for the determination of the above-mentioned aflatoxins in wheat samples are also presented. (C) 2002 Elsevier Science B.V. All rights reserved.

Papst, C., H. F. Utz, et al. (2005). "Mycotoxins produced by Fusarium spp. in isogenic Bt vs. non-Bt maize hybrids under European corn borer pressure." Agronomy Journal 97(1): 219-224. ://000226783300030 AND http://www.botanischergarten.ch/Bt/Papst-Mycotoxin-Fusarium-2005.pdf Stalk and ear rots caused by Fusarium subspecies are often related to mycotoxin accumulation in maize (Zea mays L.) kernels. Various mycotoxicoses in livestock and humans are triggered by the consumption of these toxins. The European corn borer (Ostrinia nubilalis hubner) reportedly promotes the infection by Fusarium spp. The objectives of our study were to (i) evaluate the concentration of deoxinivalenol (DON), 3-acetyl-deoxynivalenol (3-A-DON), 15-acetyl-deoxynivalenol (15-A-DON), fumonisin (FUM), fusarenon-X (FUS-X), moniliformin (MON), and nivalenol (NIV) in kernels; (ii) determine the level of European corn borer (ECB) resistance; and (iii) investigate the association between the concentration of mycotoxins and ECB resistance. The study used early maturing European Bt (Bacillus thuringiensis) cultivars, their isogenic counterparts, and commercial hybrids. The field experiments were conducted at three locations in Germany. The mycotoxins most prevalent were DON, FUM, and MON. Plots infested by and protected from ECB differed significantly for DON and FUM concentrations. In addition, significant differences were found for concentrations of FUM between isogenic Bt and non-Bt hybrids. The two Bt events - Bt176 and Mon810 - were also significantly different for FUM concentrations. Not all mycotoxins were related to ECB damage. Insect management and, therefore, the use of Bt cultivars may be a short-term solution to minimize toxins in kernels.

Park, D. L. and L. Stoloff (1989). "Aflatoxin Control - How a Regulatory Agency Managed Risk from an Unavoidable Natural Toxicant in Food and Feed." Regulatory Toxicology and Pharmacology 9(2): 109-130. ://WOS:A1989U113300002

Park, J. W., E. K. Kim, et al. (2002). "Natural co-occurrence of aflatoxin B-1, fumonisin B-1 and ochratoxin A in barley and corn foods from Korea." Food Additives and Contaminants 19(11): 1073-1080. ://000179163600010 A survey for aflatoxin B-1 (AFB(1)), fumonisin B-1 and ochratoxin A (OTA) was conducted on 127 samples that included 30 food- grade barley, 32 barley foods, 18 food-grade corn and 47 corn foods, randomly collected during 1998-99 in Seoul, Korea. The presence of mycotoxins was analysed by direct competitive enzyme-linked immunosorbent assay (ELISA), and most of the positive samples from ELISA were confirmed using high- performance liquid chromatography (HPLC). Recoveries of AFB(1) and OTA spiked at 10 ng g(-1) and FB1 spiked at 50 ng g(-1) were 106, 87 and 105% by ELISA, whereas those by HPLC were 80, 79 and 84%, respectively. Detection limits by ELISA for AFB(1), FB1 and OTA were 1, 5 and 5 ng g(-1), and those by HPLC were 0.6, 35 and 1 ng g(-1). Naturally occurring AFB(1), FB1 and OTA were found in 4/32 (12%), 2/32 (6%) and 4/32 (12%) samples of barley foods with an average of 26, 16 and 9 ng g(-1), respectively. AFB(1) and FB1 in corn foods were detected in 4/47 (8%) and 9/47 (19%) samples with the average being 20 and 74 ng g(-1) while no OTA was found in any corn foods samples. No AFB(1), FB1 or OTA was detected in any of food- grade barley and corn samples. This is the first report on the natural co- occurrence of AFB(1) and FB1 in barley and corn foods as well as on surveillance of OTA in Korea.

Park, J. W., P. M. Scott, et al. (2004). "Analysis of heat-processed corn foods for fumonisins and bound fumonisins." Food Additives and Contaminants 21(12): 1168-1178. ://WOS:000226420100005 Thirty retail samples of heat-processed corn foods, i.e. corn flakes, corn-based breakfast cereals, tortilla chips and corn chips, were analysed for fumonisins fumonisin B-1 (FB1), fumonisin B-2 (FB2) and hydrolysed FB1 (HFB1) - as well as for protein- and total-bound FB1. Bound ( hidden) fumonisins cannot be detected by conventional analysis. Improved methods for the determination of bound FB1 were developed. The protein-bound FB1 was extracted with 1% sodium dodecylsulfate (SDS) solution. The SDS, which interfered with high-performance liquid chromatography ( HPLC) analysis, was then separated from protein-bound FB1 by complexing with methylene blue followed by solvent extraction and hydrolysis with 2N KOH. To measure total-bound FB1, the sample itself was hydrolysed with KOH. In both cases, cleanup was accomplished on an OASIS polymeric solid-phase extraction column and the bound fumonisins were determined by HPLC measurement of HFB1. Fourteen of 15 samples of corn flakes and other corn-based breakfast cereals analysed contained detectable levels of FB1 with a mean in positive samples of 67 ng g(-1) (13 - 237 ng g(-1)). Two samples also had detectable levels of FB2 (21 - 23 ng g(-1)). Bound FB1 was found in all samples; the mean protein- bound FB1 measured was 58 ng g(-1) (22 - 176 ng g(-1)) and the mean total-bound FB1 measured was 106 ng g(-1) (28 - 418 ng g(-1)), reported as FB1 equivalents after correction for recoveries of HFB1. There was an average of about 1.3 times more FB1 in the bound form compared with extractable FB1, and this was about twice as much as protein-bound FB1. Seven of the 15 samples of alkali-processed corn- based foods, such as tortilla chips and corn chips, contained FB1 and three contained HFB1 with means in measurable positive samples of 78 (48 - 134) and 29 (13 - 47) ng g(-1), respectively. Five of these alkali-processed corn foods contained bound FB1; the mean measurable protein-bound FB1 was 42 ng g(-1) (39 - 46 ng g(-1)) and the mean measurable total-bound FB1 was 100 ng g(-1) (54 - 209 ng g(-1)). HFB1 derived from bound FB1 in selected samples was confirmed by HPLC with mass spectrometry (MS).

Pascale, M., A. Visconti, et al. (1999). "Mycotoxin contamination of maize hybrids after infection with Fusarium proliferatum." Journal of the Science of Food and Agriculture 79(15): 2094-2098. ://000084669500006 The ear rot severity of nine maize hybrids and the accumulation of fumonisin B-1 (FB1), fumonisin B-2 (FB2), beauvericin (BEA) and fusaproliferin (FP) after artificial inoculation in the field with a toxigenic strain of Fusarium proliferatum have been investigated. Different degrees of ear rot were observed in different hybrids. Inoculated ears contained 11-38% of Fusarium-damaged kernels (FDK). Mycotoxin analyses showed a pronounced contamination of FDK with concentrations ranging from 116 to 343 mgkg(-1) for FB1, from 8 to 29 mgkg(-1) for FB2, from 1 to 14 mgkg(-1) for BEA and from 2 to 10 mgkg(-1) for FP. Lower levels of contamination were found in healthy- looking kernels (up to 26, 2, 0.2 and 0.3 mgkg(-1) for FB1, FE2, BEA and FP respectively). A good correlation was observed between mycotoxin contamination and the Fusarium ear rot index, calculated on the basis of average ear infection with a scale ranging from 0 to 500 to represent healthy cobs and totally rotted cobs respectively. (C) 1999 Society of Chemical Industry.

Pascale, M., A. Visconti, et al. (2002). "Ear rot susceptibility and mycotoxin contamination of maize hybrids inoculated with Fusarium species under field conditions." European Journal of Plant Pathology 108(7): 645-651. ://000178595700006 The development of new maize hybrids with resistance to Fusarium infection is an effective means of minimizing the risk of mycotoxin contamination. Several maize hybrids have been investigated for Fusarium ear rot and accumulation of fumonisin B-1 (FB1), fumonisin B-2 (FB2), beauvericin (BEA) and fusaproliferin (FP) after artificial inoculation in the field with toxigenic strains of Fusarium verticillioides and Fusarium proliferatum. The year of inoculation had a significant influence on the disease severity and mycotoxin accumulation in maize kernels. Of all the hybrids tested, only Mona exhibited resistance to ear rot caused by F. verticillioides and produced low levels of fumonisins during three years of experiments. In Fusarium-damaged kernels (FDK), fumonisin B-1, fumonisin B-2,B- beauvericin and fusaproliferin were detected at concentrations much higher (up to 10-20 times) than in healthy-looking kernels (HLK). Animal and human exposure to these mycotoxins can be drastically reduced by removing mouldy and visibly damaged kernels from the commodity.

Pascale, M., A. Visconti, et al. (2002). "Accumulation of fumonisins, beauvericin and fusaproliferin in maize hybrids inoculated under field conditions with Fusarium proliferatum." Mycological Research 106: 1026-1030. ://000179299000005 The ear rot severity of 15 maize hybrids and the accumulation of fumonisin B-1 (FB1), fumonisin B-2 (FB2), beauvericin (BEA) and fusaproliferin (FP) after artificial inoculation in the field with a toxigenic strain of Fusarium proliferatum has been investigated in Poland during the seasons 1996, 1997 and 1999. The year of inoculation proved a significant influence on ear infection degree and mycotoxin accumulation. Inoculated ears contained 11-71 % Fusarium-damaged kernels. Mycotoxins were detected in all hybrids at levels of 18-231.9 mug g(-1) for FB1, 0.4-26.5 mug g(-1) for FB2, 0.2-19.6 mug g(-1) for BEA and 0.3-6.4 mug g(-1) for FP. Mycotoxin concentrations were higher in Fusarium-damaged kernels (up to 361.5, 41.1, 44.3 and 10.0 mug g(-1) for FB1, FB2, BEA and FP, respectively) than in healthy-looking kernels (up to 26.0, 2.3, 1.9, 0.3 mug g(-1) for FB1, FB2, BEA and FP, respectively). All hybrids showed high susceptibility to the fungal infection and high toxin content in kernels during the three years of investigation.

Patino, B., S. Mirete, et al. (2004). "PCR detection assay of fumonisin-producing Fusarium verticillioides strains." Journal of Food Protection 67(6): 1278-1283. ://000221897200033 Fusarium verticillioides is considered to be the main source of fumonisins, a group of toxins that contaminate commodities and result in chronic and acute diseases affecting humans and animals. The detection and control of this species is crucial to prevent fumonisins from entering the food chain. The objective of the present research was to develop a specific, sensitive, and robust PCR assay to detect F. verticillioides strains using two pairs of specific primers for F. verticillioides, which have been designed on the basis of the intergenic spacer region of the rDNA units. The first pair of primers was F. verticillioides species specific, whereas the second pair of primers detected fumonisin-producing F. verticillioides strains. This second pair of primers allowed for the discrimination between the major group of F. verticillioides strains, fumonisin-producing strains that are mainly associated with crops, and a minor group of strains, non-fumonisin-producing strains that are associated with bananas. Fifty-four strains of F. verticillioides from different geographical regions and hosts were tested using both sets of primers. Sixteen additional Fusarium species were examined. The specificity of the primer sequences provides the basis for a simple, rapid, accurate, and sensitive detection and identification method of this fungal species that represents a risk for human and animal health.

Paul, C., G. Naidoo, et al. (2003). "Quantitative trait loci for low aflatoxin production in two related maize populations." Theoretical and Applied Genetics 107(2): 263-270. ://000184029100009 Aflatoxin B-1 formed by Aspergillus flavus Fr:Link has been associated with animal disease and liver cancer in humans. We performed genetic studies in progenies derived from maize inbred Tex6, associated with relatively low levels of aflatoxin production, crossed with the historically important inbred B73. (Tex6xB73) x B73 BC1S1 and Tex6 x B73 F-2:3 mapping populations were produced and evaluated in 1996 and 1997 in Champaign, Ill. Ears were inoculated 20 to 24 days after midsilk using a pinboard method and a mixture of conidia of A. flavus Link:Fr. isolates. Aflatoxin B-1 levels in harvested ears were determined using an indirect competitive ELISA. Molecular markers were assayed on the populations and used to generate maps. Molecular marker - QTL associations for lower levels of aflatoxin production were determined using multiple regression (MR) and composite interval analysis with multiple regression (CIM MR). MR revealed sets of markers associated with lower aflatoxin production in 1996 and 1997, and CIM MR detected a smaller subset of loci significant in 1997. QTLs for lower aflatoxin were attributed to both Tex6 and B73 parental sources. Environment strongly influenced the detection of QTLs for lower aflatoxin production in different years. There were very few chromosome regions associated with QTLs in more than 1 year or population with MR analysis, and none with CIM MR analysis. In 1997, QTLs for lower aflatoxin were detected with CIM MR in bins 5.01-2 and 5.04-5 in the BC1S1 population, and in bins 3.05-6, 4.07-8 and 10.05-10.07 in the F-2:3 population. These QTL associations appear the most promising for further study.

Payne, G. A. and M. P. Brown (1998). "Genetics and physiology of aflatoxin biosynthesis." Annual Review of Phytopathology 36: 329-362. ://000076116000015 Aflatoxins are the most thoroughly studied mycotoxins, Elegant early research on the biosynthetic scheme of the pathway has allowed a molecular characterization of aflatoxin biosynthesis and its regulation. Genetic studies on aflatoxin biosynthesis in Aspergillus flavus and A. parasiticus, and sterigmatocystin biosynthesis in A. nidulans, led to the cloning of 17 genes responsible for 12 enzymatic conversions in the AF/ST pathways. Pathway-specific regulation is by a Zn(II)2Cys6 DNA-binding protein that regulates the transcription of all pathway genes. Less is known about the global factors that regulate aflatoxin biosynthesis, but there is a clear link between development and aflatoxin biosynthesis. There is also a large body of information on physiological factors involved in aflatoxin biosynthesis, but it has been difficult to understand their role in the regulation of this pathway. This chapter discusses current knowledge on the molecular biology and genetics of the pathway, and provides a summary of the physiological factors known to influence aflatoxin formation.

Payne, G. A., G. J. Nystrom, et al. (1993). "Cloning of the Afl-2 Gene Involved in Aflatoxin Biosynthesis from Aspergillus-Flavus." Applied and Environmental Microbiology 59(1): 156-162. ://A1993KF24900026 Aflatoxins are extremely potent carcinogens produced by Aspergillus flavus and Aspergillus parasiticus. Cloning of genes in the aflatoxin pathway provides a specific approach to understanding the regulation of aflatoxin biosynthesis and, subsequently, to the control of aflatoxin contamination of food and feed. This paper reports the isolation of a gene involved in aflatoxin biosynthesis by complementation of an aflatoxin- nonproducing mutant with a wold-type genomic cosmid library of A. flavus. Strain 650-33, blocked in aflatoxin biosynthesis at the afl-2 allele, was complemented by a 32-kb cosmid clone (B9), resulting in the production of aflatoxin. The onset and profile of aflatoxin accumulation was similar for the transformed strain and the wild-type strain (NRRL 3357) of the fungus, indicating that the integrated gene is under the same control as in wild-type strains. Complementation analyses with DNA fragments from B9 indicated that the gene resides within a 2.2-kb fragment. Because this gene complements the mutated afl- 2 allele, it was designated afl-2. Genetic evidence obtained from a double mutant showed that afl-2 is involved in aflatoxin biosynthesis before the formation of norsolorinic acid, the first stable intermediate identified in the pathway. Further, metabolite feeding studies with the mutant, transformed, and wild-type cultures and enzymatic activity measurements in cell extracts of these cultures suggest that afl-2 regulates gene expression or the activity of other aflatoxin pathway enzymes. This is the first reported isolation of a gene for aflatoxin biosynthesis in A. flavus.

Pazzi, F., M. Lener, et al. (2006). "Bt maize and mycotoxins: the current state of research." Annals of Microbiology 56(3): 223-230. ://WOS:000241262100007 The commercialisation of Bt (Bacillus thuringensis) maize expressing the Cry endotoxin specific for some types of Lepidopteran and Coleopteran pests has lead researchers to study the reduction in mycotoxin concentrations in Bt hybrids compared to the correspondent isogenic plants. Indeed, insect damage is one of the main inoculation pathways of mycotoxinogenic moulds. The present study aims to evaluate, according to the scientific literature published to date, the real efficiency of Bt maize hybrids in reducing the mycotoxin problem. The results obtained from the analysis of the literature do not show significant variations in the content of aflatoxins, zearalenone and trichothecenes, between Bt hybrids and corresponding isogenic control plants. The only mycotoxins where Bt hybrids have any effect are the fumonisin group, but even in this case studies in commercially planted fields have shown that their effect is mitigated by many biotic and abiotic factors.

Pearson, T. C., D. T. Wicklow, et al. (2001). "Detecting aflatoxin in single corn kernels by transmittance and reflectance spectroscopy." Transactions of the Asae 44(5): 1247-1254. ://000172990200026 Transmittance spectra (500 to 950 nm) and reflectance spectra (550 to 1700 nm) were analyzed to determine if they could be used to distinguish aflatoxin contamination in single whole corn kernels. Spectra were obtained on whole com kernels exhibiting various levels of bright greenish-yellow fluorescence. Afterwards, each kernel was analyzed for aflatoxin following the USDA-FGIS Aflatest affinity chromatography procedures. Spectra were analyzed using discriminant analysis and partial least squares regression. More than 95% of the kernels were correctly classified as containing either high (> 100 ppb) or low (< 10 ppb) levels of aflatoxin. Classification accuracy for kernels between 10 and 100 ppb was only about 25%, but these kernels do not usually affect total sample concentrations and are not as important. Results were similar when using either transmittance or reflectance, and when using either discriminant analysis or partial least squares regression. The two-feature discriminant analysis of transmittance data gave the best results. However for automated high-speed detection and sorting, instrumentation that uses single-feature reflectance spectra may be more practically implemented. This technology should provide the corn industry with a valuable tool for rapidly detecting aflatoxin in com.

Pearson, T. C., D. T. Wicklow, et al. (2004). "Reduction of aflatoxin and fumonisin contamination in yellow corn by high-speed dual-wavelength sorting." Cereal Chemistry 81(4): 490-498. ://000222743700011 A high-speed dual-wavelength sorter was tested for removing corn contaminated in the field with aflatoxin and fumonisin. To achieve accurate sorting, single kernel reflectance spectra (500-1,700 nm) were analyzed to select the optimal pair of optical filters to detect mycotoxin-contaminated corn during high-speed sorting. A routine, based on discriminant analysis, was developed to select the two absorbance bands in the spectra that would give the greatest classification accuracy. In a laboratory setting, and with the kernels stationary, absorbances at 750 and 1,200 nm could correctly identify >99% of the kernels as aflatoxin-contaminated (>100 ppb) or uncontaminated. A high-speed sorter was tested using the selected filter pair for corn samples inoculated with Aspergillus flavus; naturally infested corn grown in central Illinois; and naturally infested, commercially grown and harvested corn from eastern Kansas (2002 harvest). For the Kansas corn, the sorter was able to reduce aflatoxin levels by 81% from an initial average of 53 ppb, while fumonisin levels in the same grain samples were reduced an average of 85% from an initial level of 17 ppm. Similar reductions in mycotoxin levels were observed after high-speed sorting of A. flavus inoculated and naturally mold-infested corn grown in Illinois.

Pennington, L. J. (1986). "Thin-Layer Chromatography and Densitometric Determination of Aflatoxins in Mixed Feeds Containing Citrus Pulp." Journal of the Association of Official Analytical Chemists 69(4): 690-696. ://WOS:A1986D487400033 AND http://www.botanischergarten.ch/Bt/Pennington-Thin-Layer-Aflatoxins-Citrus-1986.pdf

Pepo, P. (2006). "Improvement of effectiveness in maize breeding." Acta Agronomica Hungarica 54(3): 351-358. ://BIOSIS:PREV200700053747 Plant regeneration via tissue culture is becoming increasingly more common in monocots such as maize ( Zea mays L.). Pollen ( gametophytic) selection for resistance to aflatoxin in maize can greatly facilitate recurrent selection and the screening of germplasm for resistance at much less cost and in a shorter time than field testing. In vivo and in vitro techniques have been integrated in maize breeding programmes to obtain desirable agronomic attributes, enhance the genes responsible for them and speed up the breeding process. The efficiency of anther and tissue cultures in maize and wheat has reached the stage where they can be used in breeding programmes to some extent and many new cultivars produced by genetic manipulation have now reached the market.

Pestka, J. J., J. I. Azconaolivera, et al. (1994). "Comparative-Assessment of Fumonisin in Grain-Based Foods by Elisa, Gc-Ms, and Hplc." Journal of Food Protection 57(2): 169-172. ://A1994MW75600016

Picco, M., A. Nesci, et al. (1999). "Aflatoxin B-1 and fumosin B-1 in mixed cultures of Aspergillus flavus and Fusarium proliferatum on maize." Natural Toxins 7(6): 331-336. ://000166017400015 Production of aflatoxin B-1 and fumonisin B-1 in pure and mixed cultures of Aspergillus flavus and Fusarium proliferatum were determined on irradiated maize seeds inoculated with different spore concentrations at 0.97 water activity (a(w)) and a temperature of 25 degreesC. The highest levels of aflatoxin B-1 were produced by A. flavus at the lowest levels of inoculum (10(3) spore ml(-1)). There was no spore concentration influence on fumonisin B-1 production after 10, 20 and 35 days of incubation. When A. flavus was co-inoculated with F. proliferatum, aflatoxin B-1 production was inhibited. The higher the inocula levels of Fusarium produced, the higher the inhibition and this inhibition increased during the incubation period. Total inhibition was reached at 35 days of incubation. There was no interaction influence on fumonisin B-1 production at ail inoculum levels assayed. These results suggest that under optimal environ mental conditions of substrate, water activity and temperature, the interaction between A. flavus and F. proliferatum could produce inhibition of aflatoxin B-1 and stimulation of fumonisin B-1. Copyright (C) 1999 John Wiley & Sons, Ltd.

Pietri, A., T. Bertuzzi, et al. (2004). "Occurrence of mycotoxins and ergosterol in maize harvested over 5 years in Northern Italy." Food Additives and Contaminants 21(5): 479-487. ://000221241900009 AND http://www.botanischergarten.ch/Bt/Pietri-Ocurrence-Mycotoxins-2004.pdf Maize samples collected from storage bins and feed mills in Northern Italy between 1995 and 1999 were surveyed for the occurrence of aflatoxin B-1 (AFB(1)), zearalenone (ZEA), deoxynivalenol ( DON) and fumonisin (FB1); further, ergosterol was analysed as a fungal growth marker. The incidence and mean content of AFB(1) were generally low; nevertheless, a remarkable contamination was found in two samples ( 109 and 158 mug kg(-1)), while five others exceeded 20 mug kg(-1). DON and ZEA mean levels were significantly higher in 1996 (2716 and 453 mug kg(-1)) with respect to the other years, when mean contents ranged from 7 to 30% and from 3 to 17%, respectively, expressed in per cent of 1996 contents. FB1 was present in all samples and was by far the most remarkable mycotoxin in Northern Italian maize, with the exception of samples from 1996. The average level was 3064 mug kg(-1), 69.6% of samples resulted over 1000 mug kg(-1) and 16.9% over 5000 mug kg(-1). Significant correlations were found between ergosterol and the major mycotoxin(s) in each year (FB1 in 1995 and 1997-99; ZEA + DON in 1996). Consequently, ergosterol seems to be a good index of the toxicological quality of maize. Climatic conditions influenced the growth of different fungal species. In 1996, the first 20 days of October were extremely rainy; these weather conditions delayed the harvest until the first week of November and favoured the growth of DON and ZEA producing fungi and the synthesis of mycotoxins. On the contrary, the temperate and dry climate of the other years supported the growth of FB1- producing fungi.

Pineda-Valdes, G., D. Ryu, et al. (2002). "Reduction of moniliformin during alkaline cooking of corn." Cereal Chemistry 79(6): 779-782. ://000179093500007 The incidence of moniliformin (MON) producing Fusarium spp. in selected corn (Zea mays L.) samples from Mexico and the United States and the effects of alkaline cooking and the tortilla manufacturing processes on the reduction of MON were determined. The percentage of infected kernels with Fusarium spp. ranged from 0 to 22% in eight food-grade corn samples, including six from Mexico and two from the United States. Complete (100%) reduction of MON was observed when a naturally contaminated corn sample containing 1.4 mug of MON/g of corn was used in a pilot-scale alkaline cooking and tortilla manufacturing process. In a companion laboratory-scale study, using a cultured corn sample containing 17.6 mug of MON/g of corn, a 71% reduction of the toxin was observed during the process. Alkaline cooking appeared to be an effective method for reduction of MON in corn.

Pineiro, M. S., G. E. Silva, et al. (1997). "Fumonisin levels in Uruguayan corn products." Journal of Aoac International 80(4): 825-828. ://WOS:A1997XL99800017 A survey was conducted to evaluate fumonisins FB1 and FB2 in Uruguayan corn products. Sixty-four samples of different local brands were purchased from retail stores during a 15-month period and analyzed for FB1 and FB2 by methanol-water extraction, cleanup with a 1 mL, strong-anion-exchange solid-phase extraction column, and liquid chromatography with o-pthaldialdehyde-2- mercaptoethanol derivatization and fluorescence detection. Contamination levels for FB1 varied from 50 ng/g (detection limit) to 6342 ng/g. Values were highest in feed samples (up to 6342 ng/g), unprocessed corn kernel (up to 3688 ng/g), and milled products, which included polenta (up to 427 ng/g). They were lowest in processed corn kernel (up to 155 ng/g) and snacks (up to 314 ng/g). FB2 was determined in one-fourth of the total samples and detected at trace levels in only one feed sample. The data demonstrated the natural occurrence of fumonisins in corn products in Uruguay. Feed and polenta that contain fumonisins could be of concern because they are consumed in large amounts and are often the main nutrient source in Uruguay.

Pinson, L., M. P. Plancke, et al. (2003). "Fusarium mycotoxins in isogenic and Bt maize varieties grown in different geographic areas in France." Advances in Stored Product Protection: 511-516. ://BIOSIS:PREV200600077183 Four maize varieties collected in four sites in France in 2000, with and without the character of resistance to insect borers (Bt character), were compared for Fusarium spp. contamination and mycotoxin production in kernels (trichothecenes, fumonisins, zearalenone). For three of the considered varieties, lower Fusarium contamination and mycotoxin content were observed on Bt hybrid maize than on the corresponding isogenic variety. Fumonisin concentrations ranged from 9.5 ppb to 307 ppb for Bt varieties, and from < 3ppb to 1300 ppb for isogenic ones. Low concentrations of trichothecenes were measured in transgenic as well as in traditional maize. With the exception of two of 15 samples, zearalenone concentrations were below the 200-ppb limit recommended in France. Although not significantly different, these results suggest a decrease in mycotoxins kernels content linked to Bt hybrid.

Piramanayagam, S. and V. T. George (2002). "Effect of dietary fumonisin mycotoxin on the growth rate of broiler chicken." Indian Veterinary Journal 79(10): 1022-1025. ://000178673000007

Pirttila, A. M., L. M. McIntyre, et al. (2004). "Expression profile analysis of wild-type and fec1 mutant strains of Fusarium verticillioides during fumonisin biosynthesis." Fungal Genetics and Biology 41(6): 647-656. ://000221440100006 Fusarium verticillioides produces a group of mycotoxins known as fumonisins that are associated with a variety of mycotoxicoses in humans and animals. In this study, DNA microarrays were constructed with expressed sequence tags (ESTs) from F verticillioides. To identify genes with patterns of expression similar to the fumonisin biosynthetic (FUM) genes, the microarray was probed with labeled cDNAs originating from a wild-type strain and a fccl mutant grown on maize and in a defined medium adjusted to either pH 3 or pH 8. The comparative analyses revealed differential expression of genes corresponding to 116 ESTs when the fungal strains were grown on maize. Under different pH conditions, 166 ESTs were differentially expressed, and 19 ESTs were identified that displayed expression patterns similar to the FUM ESTs. These results provide candidate genes with potential roles in fumonisin biosynthesis. (C) 2004 Elsevier Inc. All rights reserved.

Pitt, J. I. (2000). "Toxigenic fungi: which are important?" Medical Mycology 38: 17-22. http://www.ingenta.com/isis/searching/Expand/ingenta?pub=infobike://rsm/bmb/2000/00000056/00000001/art00016 Growth of commonly occurring filamentous fungi in foods may result in production of mycotoxins, which can cause a variety of ill effects in humans, from allergic responses to immunosuppression and cancer. According to experts, five kinds of mycotoxins are important in human health around the world: aflatoxins, ochratoxin A, fumonisins, certain trichothecenes, and zearalenone. These toxins are produced by only a few species of fungi, in a limited range of commodities. Aflatoxins are potent carcinogens, produced by Aspergillus flavus and A. parasiticus in peanuts, maize and some other nuts and oilseeds. Ochratoxin A is a kidney toxin and probable carcinogen. It is produced by Penicillium verrucosum in cereal grains in cold climates, by A. carbonarius in grapes, wines and vine fruits, and by A. ochraceus sometimes in coffee beans. Fumonisins, which may cause oesophageal cancer, are formed by Fusarium moniliforme and F. proliferatum, but only in maize. Trichothecenes are highly immunosuppressive and zearalenone causes oestrogenic effects; both are produced by F. graminearum and related species. Current reporting probably under-estimates the effect of mycotoxins as a cause of human mortality.

Placinta, C. M., J. P. F. D'Mello, et al. (1999). "A review of worldwide contamination of cereal grains and animal feed with Fusarium mycotoxins." Animal Feed Science and Technology 78(1-2): 21-37. ://000079535900003 AND http://www.botanischergarten.ch/Bt/Placinta-Review-Fusarium-Feed-1999.pdf From a global perspective, three classes of Fusarium mycotoxins may be considered to be of particular importance in animal health and productivity. Within the trichothecene group, deoxynivalenol (DON) is widely associated with feed rejection in pigs, while T-2 toxin can precipitate reproductive disturbances in sows. Another group comprising zearalenone (ZEN) and its derivatives is endowed with oestrogenic properties. The third category includes the fumonisins which have been linked with specific toxicity syndromes such as equine leukoencephalomalacia (ELEM) and porcine pulmonary oedema. Many toxigenic species of Fusarium are also common pathogens of cereal plants, causing diseases such as head blight of wheat and barley and ear rut of maize. Consequently, when cereal plants are infected with these fungi, there is a risk that grain may become contaminated with Fusarium mycotoxins and that these may subsequently be transferred to compound feeds. The surveillance of grain and animal feed for the occurrence of Fusarium mycotoxins continues to attract worldwide attention and has been the subject of extensive investigations over recent years. For example, high incidence rates of contamination with DON and another trichothecene, nivalenol (NIV), have been reported in maize samples in New Zealand. In Poland, unacceptably high values (up to 927 mg/kg) for DON were recorded for maize grain and cobs. Potentially harmful levels of DON (up to 40 mg/kg) were also observed in wheat produced in Germany, Poland, Japan, New Zealand, USA, Canada and Argentina. Samples of barley grain in Norway, Japan and USA were found with DON levels of up to 71 mg/kg. In the Norwegian study oat samples were also contaminated with DON at levels ranging from 7 to 62 mg/kg grain. Abnormally high concentrations of both NIV and ZEN have been observed in some Japanese barley samples (up to 26 and 15 mg/kg, respectively), and in maize produced in New Zealand (up to 7 and 10.5 mg/kg, respectively). Other trichothecenes such as 3-acetyl DON, diacetyoxyscirpenol (DAS), T-2 toxin and HT-2 toxin have also been found in cereals and animal feed in both temperate and tropical countries. In Uruguay all samples of maize-based animal feeds tested were positive for fumonisin B-1 (FB1). However, highest FB1 values were observed in South Africa for compound feed (11 000 mu g/kg), and in Thailand and China for maize (18 800 and 25 970 mu g/kg, respectively). In a study of Argentinian maize, FB2 was the major fumonisin at values of up to 11 300 mu g/kg. An alarming feature of several surveys is that in the tropics in particular, several Fusarium mycotoxins may co-occur with each other and with anatoxin B-1, an Aspergillus compound sharing carcinogenic properties with fumonisins. It is concluded that, although sample size has been small in a number of surveys, there is nevertheless unequivocal evidence of global contamination of cereal grains and animal feed with several trichothecenes, ZEN and fumonisins. Furthermore, it is clear that legislation for the control of these mycotoxins in animal feed is now overdue and that further work is required to exploit cereal genotypes that are resistant to diseases caused by toxigenic Fusarium phytopathogens. (C) 1999 Elsevier Science B.V. All rights reserved.

Plattner, R. D., A. E. Desjardins, et al. (1996). "Identification and characterization of strains of Gibberella fujikuroi mating population A with rare fumonisin production phenotypes." Mycologia 88(3): 416-424. ://A1996UT08700010 A survey of 245 strains of Gibberella fujikuroi mating population A (anamorph Fusarium moniliforme) isolated primarily from maize and sorghum in North America identified strains with three rare fumonisin production phenotypes. In liquid culture and on a maize solid substrate, several strains produced fumonisin B-2 (FB2) or B-3 (FB3), but not fumonisin B-1 (FB1), suggesting a defect in hydroxylation of C-5 or C-10. Several strains were nonproducers of fumonisins in liquid culture and low producers of fumonisins (0- 600 mu g/g FB1, FB2 and FB3) on maize substrate. The heritability of fumonisin production on maize was studied by crossing fumonisin low-producing and non- producing strains with fumonisin high-producing strains. Random ascospore and tetrad progeny were analyzed by gas chromatography-mass spectroscopy and high performance liquid chromatography for their ability to produce fumonisins on maize substrate. Although most of these crosses were pearly fertile, in one cross the ability to produce high levels of fumonisins segregated as a single gene, designated fum4, or group of closely linked genes. Allelism tests showed that fum4 was linked to, but not allelic with, the fum1 locus that was previously identified in strains of mating population A from Nepal.

Pons, W. A., L. S. Lee, et al. (1980). "Revised Method for Aflatoxins in Cottonseed Products, and Comparison of Thin-Layer and High- Performance Liquid-Chromatography Determinative Steps - Collaborative Study." Journal of the Association of Official Analytical Chemists 63(4): 899-906. ://WOS:A1980KB73400040

Prasongsidh, B. C., K. Kailasapathy, et al. (1999). "Influence of manufacturing and storing of ice cream on cyclopiazonic acid." Milchwissenschaft-Milk Science International 54(3): 141-144. ://000079961400007 Toxicity of cyclopiazonic acid (CPA) in humans of was reported. The appearance of CPA in animal and its carry-over into milk of lactating animals emphasised the potential risk to dairy consumers. However, the stability of CPA to freezing during the manufacture using contaminated milk and subsequent storage of frozen dairy products such as ice cream has not been reported. The objective of this study was to assess the stability of CPA to freezing during the preparation of ice cream and its storage over 3 months by using artificially contaminated raw whole milk at 1 mu g CPA.g(-1) Hot and cold treatment during the manufacture of ice cream did not greatly affect levels of CPA in the mix; reduction of CPA levels from mixing until ageing was nearly 12% in total. However, following pasteurisation, ageing at 4 degrees C overnight had a slight effect on CPA levels (2% decrease). Storage of 9 weeks at -20 degrees C appeared to adequately limit the loss of CPA, but significant decrease of CPA levels was observed in ice cream after 4 weeks (5%) and 9 weeks (12%) of storage. It appears that if milk contained the carry over CPA, the manufacture and storage of the ice cream made with contaminated milk would not greatly affect the stability of this neurotoxic mycotoxin in the product. The potential of CPA to reach dairy consumers will be high if ice cream is made from a high level CPA contaminated milk.

Proctor, R. H., D. W. Brown, et al. (2003). "Co-expression of 15 contiguous genes delineates a fumonisin biosynthetic gene cluster in Gibberella moniliformis." Fungal Genetics and Biology 38(2): 237-249. ://000181566600009 Fumonisins are mycotoxins produced by the maize pathogen Gibberella moniliformis and are associated with cancer in rodents. In this study, we determined the nucleotide sequence of a 75-kb region of G. monilijformis DNA and identified 18 heretofore undescribed genes flanking a cluster of five previously identified fumonism biosynthetic (FUM) genes. Ten of the newly identified genes downstream of the cluster were coregulated with FUM genes and exhibited patterns of expression that were correlated with fumonisin production. BLASTX analyses indicated that the predicted functions of proteins encoded by the 10 genes were consistent with activities expected for fumonisin biosynthesis or self-protection. These data indicate that the 10 newly identified genes and the previously identified FUM genes constitute a fumonisin biosynthetic gene cluster. Disruption of two of the new genes, encoding longevity assurance factors, had no apparent effect on fumonisin production, but disruption of a third, encoding an ABC transporter, had a subtle effect on ratios of fumonisins produced. Published by Elsevier Science (USA).

Proctor, R. H., A. E. Desjardins, et al. (2002). "Genetic analysis of the role of trichothecene and fumonisin mycotoxins in the virulence of Fusarium." European Journal of Plant Pathology 108(7): 691-698. ://000178595700012 The phytotoxicity of the Fusarium trichothecene and fumonisin mycotoxins has led to speculation that both toxins are involved in plant pathogenesis. This subject has been addressed by examining virulence of trichothecene and fumonisin-nonproducing mutants of Fusarium in field tests. Mutants were generated by transformation-mediated disruption of genes encoding enzymes that catalyze early steps in the biosynthesis of each toxin. Two economically important species of Fusarium were selected for these studies: the trichothecene-producing species Fusarium graminearum, which causes wheat head blight and maize ear rot, and the fumonisin- producing species F. verticillioides, which causes maize ear rot. Trichothecene-non-producing mutants of F. graminearum caused less disease than the wild-type strain from which they were derived on both wheat and maize, although differences in virulence on maize were not observed under hot and dry environmental conditions. Genetic analyses of the mutants demonstrated that the reduced virulence on wheat was caused by the loss of trichothecene production rather than by a non-target mutation induced by the gene disruption procedure. Although the analyses of virulence of fumonisinnon-producing mutants of F. verticillioides are not complete, to date, the mutants have been as virulent on maize ears as their wild-type progenitor strains. The finding that trichothecene production contributes to the virulence of F. graminearum suggests that it may be possible to generate plants that are resistant to this fungus by increasing their resistance to trichothecenes. As a result, several researchers are trying to identify trichothecene resistance genes and transfer them to crop species.

Proctor, R. H., A. E. Desjardins, et al. (1999). "Biosynthetic and genetic relationships of B-series fumonisins produced by Gibberella fujikuroi mating population A." Natural Toxins 7(6): 251-258. ://000166017400005 Fumonisins are mycotoxins produced by the maize pathogen Gibberella fujikuroi mating population A and frequently contaminate maize. Wild-type G. fujikuroi produces four B- series fumonisins, FB1, FB2, FB3 and FB4. These toxins are identical in structure except for the number and positions of hydroxyls along their linear carbon backbone. To elucidate the genetic and biosynthetic relationships among these fumonisins, we conducted meiotic and biochemical analyses of G. fujikuroi mutants with altered fumonisin production that resulted from defective alleles at three loci, Fum1, Fum2 and Fum3. These mutants produced either no fumonisins, only FB2 and FB4, or only FB3 and FB4. Genetic analyses revealed the orientation of the Fum loci along linkage group 1 of the fungus. The mutants were grown together in pair-wise combinations to determine if their fumonisin production phenotypes could be complemented. When FB3- and FB2-producing mutants were grown together, complementation occurred. However, when a nonproducing mutant was grown with a FB2- or FB3-producing mutant, complementation did not occur or was incomplete. When purified FB2, FB3 or FB4 was fed to mutant cultures, FB4 was converted primarily to FB2, FB3 was converted to FB1 and FB2 was not converted. The results from these assays suggest a previously unrecognized branch in the fumonisin biosynthetic pathway. Published in 1999 by John Wiley & Sons, Ltd.

Proctor, R. H., A. E. Desjardins, et al. (1999). "A polyketide synthase gene required for biosynthesis of fumonisin mycotoxins in Gibberella fujikuroi slating population A." Fungal Genetics and Biology 27(1): 100-112. ://000081854100009 Fumonisins are toxins associated with several mycotoxicoses and are produced by the maize pathogen Gibberella fujikuroi mating population A (MP-A), Biochemical analyses indicate that fumonisins are a product of either polyketide or fatty acid biosynthesis. To isolate a putative polyketide synthase (PKS) gene involved in fumonisin biosynthesis, we employed PCR with degenerate PKS primers and a cDNA template prepared from a fumonisin-producing culture of G. fujikuroi. Sequence analysis of the single PCR product and its flanking DNA revealed a gene (FUM5) with a 7.8-kb coding region. The predicted FUM5 translation product was highly similar to bacterial and fungal Type I PKSs, Transformation of a cosmid clone carrying FUM5 into G. fujikuroi enhanced production in three strains and restored wild-type production in a fumonisin nonproducing mutant. Disruption of FUM5 reduced fumonisin production by over 99% in G. fujikuroi MP-A. Together, these results indicate that FUM5 is a PKS gene required for fumonisin biosynthesis. (C) 1999 Academic Press.

Proctor, R. H., T. M. Hohn, et al. (1995). "Tri6 Encodes an Unusual Zinc-Finger Protein Involved in Regulation of Trichothecene Biosynthesis in Fusarium Sporotrichioides." Applied and Environmental Microbiology 61(5): 1923-1930. ://A1995QW18400040 In fusarium sporotrichioides, several genes required for biosynthesis of the trichothecene mycotoxin T-2 toxin are closely linked. Further characterization of this gene cluster has revealed a gene, Tri6, that specifies a 217-amino-acid protein with regions similar to Cys(2)His(2) zinc finger proteins. Temporal expression of Tri6 is similar to that of trichothecene biosynthetic pathway genes. Analysis of Tri6 transcripts indicated that transcription is initiated in two regions and that within each region there may be at least four initiation sites. Disruption of Tri6 resulted in a mutant that did not produce trichothecenes but that did accumulate low levels of the trichothecene precursor trichodiene. The Tri6 mutant was unable to convert six trichothecene biosynthetic intermediates to T-2 toxin, and transcription of two biosynthetic genes, Tri4 and Tri5, was greatly reduced in the mutant relative to the wild type. In addition, the product of Tri6 functioned as a transcriptional activator in Saccharomyces cerevisiae when fused to the DNA binding region of GAL4. These results indicate that Tri6 encodes a protein involved in the transcriptional regulation of trichothecene biosynthetic genes in F. sporotrichioides.

Purwoko, H. M., B. Hald, et al. (1991). "Aflatoxin Content and Number of Fungi in Poultry Feedstuffs from Indonesia." Letters in Applied Microbiology 12(6): 212-215. ://WOS:A1991FR05600002 AND http://www.botanischergarten.ch/Bt/Purwoko-Aflatoxin-Indonesia-1991.pdf The content of aflatoxin and associated fungi was determined in 56 samples, including 34 of corn, 10 of soybean meal, nine of rice bran and three of broken rice, collected from different poultry farms and poultry feedmills situated around Jakarta-Bogor, Indonesia. Ninety-one per cent of the corn samples contained aflatoxins and the total concentration ranged from 22 to 6171-mu-g/kg. With rice bran, 100% of the samples were positive for aflatoxin B1, ranging from 36 to 71-mu-g/kg. No aflatoxin was detected in samples of soybean meal or broken rice. All the samples were contaminated by several fungi (8 x 10(3)-5 x 10(6) cfu/g) and further identification was limited to Aspergillus flavus and A. parasiticus. The dominant species was A. flavus (2 x 10(3)-4 x 10(6) cfu/g in corn samples, 1.0 x 10(3)-1.0 x 10(5) cfu/g in soybean meal, 2 x 10(4)-4.4 x 10(5) cfu/g in rice bran and 2 x 10(4)-6 x 10(4) cfu/g in broken rice). Some of the corn samples also contained A. parasiticus (2 x 10(3)-9.5 x 10(4) cfu/g).

Ramakrishna, N., J. Lacey, et al. (1996). "Aspergillus flavus colonization and aflatoxin B-1 formation in barley grain during interaction with other fungi." Mycopathologia 136(1): 53-63. ://A1996WV53900009

Ramljak, D., R. J. Calvert, et al. (2000). "A potential mechanism for fumonisin B-1-mediated hepatocarcinogenesis: cyclin D1 stabilization associated with activation of Akt and inhibition of GSK-3 beta activity." Carcinogenesis 21(8): 1537-1546. ://WOS:000088561800012 AND http://www.botanischergarten.ch/Bt/Ramljak-Potential-Mechanism-2000.pdf

Ranjan, K. S. and A. K. Sinha (1991). "Occurrence of Mycotoxigenic Fungi and Mycotoxins in Animal Feed from Bihar, India." Journal of the Science of Food and Agriculture 56(1): 39-47. ://A1991GE98900004 AND http://www.botanischergarten.ch/Bt/Ranjan-Occurrence-Mycotoxigenic-1991.pdf A total of 387 samples comprising animal feed, poultry feed and cattle cakes from India were examined in order to isolate mycotoxin-producing fungi as well as mycotoxins. Of 385 Aspergillus flavus group isolates 53% were capable of producing aflatoxins in liquid SMKY medium. Toxigenic strains of other mycotoxigenic .fungi, viz A ochraceus, A versicolor, Penicillium citrinum and Fusarium moniliforme, were also recorded. In feed samples, citriizin were also recorded alone or as cocontaminants. A monsoon climate together with the socioeconomic conditions of this region are important determinants for the high incidence of mycotoxins in animal food.

Ratnavathi, C. V. and R. B. Sashidhar (2000). "Changes in enzyme activities and aflatoxin elaboration in sorghum genotypes following Aspergillus parasiticus infestation." Journal of the Science of Food and Agriculture 80(12): 1713-1721. ://000089024400002 Sorghum is a relatively poor substrate for aflatoxin production compared with high-risk agricultural commodities like maize and groundnut, even though it is susceptible to fungal attack. Fungal infestation of sorghum results in a varied biochemical composition of the deteriorated grain. In this study, six sorghum genotypes (red-AON 486, IS 620; yellow-LPJ, IS 17 779; white-SPV 86, SPV 462) were inoculated with a toxigenic strain of Aspergillus parasiticus (NRRL 2999) in order to evaluate the changes in the activities of various hydrolytic enzymes (alpha- and beta-amylases, protease and lipase) in comparison with those in uninfected grains. Enzyme activities were measured at different times after fungal infestation, and the enzymatic activities were correlated with the aflatoxin production. Alpha-amylase activity was observed to be greater than beta- amylase activity in all six genotypes under both healthy and infected conditions. The increase in alpha-amylase activity during the period of infection was higher in white genotypes than in red sorghum genotypes. Alpha-amylase activity in all the genotypes increased up to day 6 after fungal infection, but was significantly lower in infected grains than in healthy grains. The variability in the basal enzyme activities among the six sorghum genotypes was quite high compared with the amount of induction of each specific enzyme due to infection and germination. Higher protease activity was observed in the infected grains than in healthy grains. The enzyme activities in high tannin red genotypes were less than those in yellow and white genotypes. The alpha- and beta-amylase activities were positively correlated (r = 0.406 and 0.436; P < 0.05) to aflatoxin production. Inherent lipase activity was highest (on day 0) in AON 486, SPV 462 and SPV 86, as compared with the activity in infected grains. The total aflatoxins produced (quantified by TLC-fluorodensitometry) were lower in red genotypes than in yellow and white genotypes, suggesting that red genotypes were least susceptible to aflatoxin elaboration among the various genotypes tested. All four aflatoxins, (B-1, B-2, G(1) and G(2)) were present in five genotypes (IS 620, LPJ, IS 17 779, SPV 86 and SPV 462) at all the stages of infection, but, aflatoxin could not be detected in the red genotype AON 486 on day 3 after infection. White genotypes SPV 86 and SPV 462) showed maximal aflatoxin (total) production on day 6 after infection. (C) 2000 Society of Chemical Industry.

Ratnavathi, C. V. and R. B. Sashidhar (2003). "Substrate suitability of different genotypes of sorghum in relation to Aspergillus infection and aflatoxin production." Journal of Agricultural and Food Chemistry 51(11): 3482-3492. ://000182932700045 Grain sorghum is often damaged by rain in the field and severely infected by grain mold, which includes Aspergillus infection and aflatoxin production. The objective of the study is to investigate the extent of aflatoxin production with Aspergillus infection in vitro in different sorghum genotypes with different pericarps, red, yellow, and white, the physical and chemical characteristics of grain during infection, and the changes in grain polyphenols and phytic acid in comparison to maize and groundnut. The physical characters and biochemical composition of sorghum grain contribute to make it less susceptible to Aspergillus infection and aflatoxin contamination compared to maize and groundnut. The lowest amounts of aflatoxin and ergosterol were observed in genotypes with red pericarp, whereas higher amounts of aflatoxin and ergosterol were found in white genotypes followed by maize and groundnut. All of the red genotypes differ in polyphenol composition and aflatoxin produced, showing resistance to mold damage. Another indication of resistance in red genotypes was the delayed peaking of aflatoxin production (9 days after infection). In red sorghum genotypes there was a significant, positive correlation existing between polyphenol content and aflatoxin produced at 3 and 6 days after infection, the r values being 0.589 and 0.513, respectively. The starch content decreased whereas the protein content in all sorghum genotypes increased during infection. Maximum phytic acid was observed in white sorghum genotypes. Phytic acid in yellow genotypes was found to have a significant negative correlation (r = -0.569) with aflatoxin produced.

Reid, L. M., R. W. Nicol, et al. (1999). "Interaction of Fusarium graminearum and F-moniliforme in maize ears: Disease progress, fungal biomass, and mycotoxin accumulation." Phytopathology 89(11): 1028-1037. ://000083329800007 To investigate the interaction between two major ear-rotting pathogens, maize ears were inoculated with either Fusarium graminearum, F. moniliforme, or an equal mixture of the two. Silk and kernel tissues were periodically harvested throughout the growing season so that a time course of the experimental variables (disease severity, ergosterol content, fungal DNA content, and mycotoxin concentration) could be recorded. Over the 3 years tested (1992 to 1994), the highest levels of disease and ergosterol were found in the F. graminearum treatment, followed by the mixture treatment (F. graminearum plus F. moniliforme) and, finally, the F. moniliforme treatment. Kernel ergosterol content and disease rating were correlated for both pathogens, but the highest correlation coefficients were obtained in the F. graminearum treatment. The DNA analysis revealed that, in the mixed inoculum, F. moniliforme had a greater growth rate than did F. graminearum. In 1994, appreciable F. moniliforme from natural inoculum was found in the F. graminearum treatment. Fumonisin B-1 levels did not differ between the F. moniliforme treatment and the mixed inoculum treatment. The effect of temperature on the growth rate of the two species explained some of the field results, with temperatures in the silks being more favorable to F. moniliforme. Data on the growth rate on silks obtained by the incorporation of radiolabeled precursor to ergosterol demonstrated that F. graminearum was able to grow well at 26 to 28 degrees C, whereas F. moniliforme grew well over a broader range, including at higher temperatures.

Reid, L. M., X. Zhu, et al. (2001). "Crop rotation and nitrogen effects on maize susceptibility to gibberella (Fusarium graminearum) ear rot." Plant and Soil 237(1): 1-14. ://000172861900001 An experiment was established in 1992 in eastern Ontario, Canada to determine the effects of crop rotation (continuous maize, soybean-maize and alfalfa-maize) and nitrogen (N) amendment [0, 100 and 200 kg N ha(-1) of fertilizer (NH4NO3), and 50 and 100 Mg ha(-1) (wet wt.) each of stockpiled and rotted dairy manure] on maize production and soil properties. From 1997 to 1999, an additional study was added to the experiment to investigate treatment effects on the susceptibility of maize hybrids to gibberella ear rot. A moderately resistant and a susceptible hybrid were planted in each plot and inoculated with a macroconidial suspension of Fusarium graminearum by both the silk channel injection and the kernel-wound techniques. At harvest, ears were rated for the severity of disease symptoms and harvested kernels were analyzed for the mycotoxin deoxynivalenol (DON). The greatest number of significant N effects were found in the continuous maize treatments and with the susceptible hybrid. Most N amendments decreased both disease severity and DON accumulation in the susceptible hybrid. The most consistent effect was a decrease in disease severity with 100 kg N ha(-1) fertilizer and an increase in disease severity with the higher rate of 200 kg N ha(-1). This study is the first to report on the effects of soil N amendments on gibberella ear rot susceptibility.

Resnik, S., S. Neira, et al. (1996). "A survey of the natural occurrence of aflatoxins and zearalenone in Argentine field maize: 1983-1994." Food Additives and Contaminants 13(1): 115-120. ://A1996TV78800012

Reynoso, M. M., A. M. Torres, et al. (2004). "Fusaproliferin, beauvericin and fumonisin production by different mating populations among the Gibberella fujikuroi complex isolated from maize." Mycological Research 108: 154-160. ://000220606000005 The production of fumonisins, fusaproliferin and beauvericin by Gibberella fujikuroi different mating populations isolated from maize in Argentina was evaluated. From 203 strains of Fusarium verticillioides (G. fujikuroi mating population A), 193 were fumonisin producers. Among members of mating population A, female fertile strains produced 20% more toxin than female sterile ones. Among 78 Fusarium proliferatum strains (G. fujikuroi mating population D) 65 produced fumonisins. The percentage of strains that were high. intermediate and low level toxin producers varied according to the species evaluated and the area from which the strains were isolated. Fusarium subglutinans (G. fujikuroi mating population E) strains produced low levels or were no fumonisin producers. Strains from both G. fujikuroi mating populations D and E were able to produce fusaproliferin and beauvericin. Among the members of F. subglutinans (G. fujikuroi mating population E) the fusaproliferin production was more constant. Co-production of fumonisin, fusaproliferin and beauvericin among the strains belonging to G. fujikuroi D and E was also observed. The co- production of fumonisin, beauvericin and fusaproliferin in maize need to be considered, since from the toxicological point of view interactions between these toxins could occur. The toxigenic ability of the strains evaluated prompt us that is necessary to determine the natural occurrence of fusaproliferin and beauvericin in Argentinean maize.

Reynoso, M. M., A. M. Torres, et al. (2002). "Efficacy of antioxidant mixtures on growth, fumonisin production and hydrolytic enzyme production by Fusarium verticillioides and F. proliferatum in vitro on maize-based media." Mycological Research 106: 1093-1099. ://000179299000012 The effect of single or mixtures of antioxidants on the lag phase prior to growth, growth rate, hydrolytic enzyme production (N- acetyl-beta-glucosaminidase, beta-D-glucosidase and alpha-D-galactosidase) and fumonisin production by Fusarium verticillioides and F. proliferatum was evaluated on maize- based media at 25 degreesC, and under different water activity (a(w)) conditions. An increase in the lag phase (h) was observed for both F. verticillioides and F. proliferatum especially with propyl paraben (PP)+butylated hydroxyanisole (BHA) treatments at all a, levels tested. For both species PP alone or in combination with BHA, at concentrations of 0.5 and I mm reduced the growth rates by > 85 % at the three a, levels tested (0.995; 0.98 and 0.95). PP+butylated hydroxytoluene (BHT) or trihydroxybutyrophenone (THBP) were less effective in controlling growth, regardless of a, level. Combinations of PP+BHA reduced the fumonisin concentrations produced by F. verticillioides and F. proliferatum at 0.995 and 0.98 a, significantly. However, at low concentrations of antioxidants (0.5 mm) some stimulation in fumonisin production was observed with some treatments. The efficacy of the treatments was reflected in the impact on enzyme production. In the untreated control the highest total enzyme activity of three hydrolytic enzymes was observed at 0.995 a, after 96 h. All the antioxidant treatments alone or combined resulted in a significant reduction (P < 0.001) of the total enzyme activity at the aw levels tested. Only 10 mm THBP produced an increase in the total amount of N-acetyl-beta-D-glucosidase by both F. verticillioides and F. proliferatum. For the three enzymes single factors: time, a, and antioxidant treatments, most two and all three way interactions were significant (P < 0.001). The use of combined mixtures of antioxidants could be a good strategy to diminish the entry of fumonisin into the animal feed and human food chains.

Rheeder, J. P., W. F. O. Marasas, et al. (1992). "Fusarium-Moniliforme and Fumonisins in Corn in Relation to Human Esophageal Cancer in Transkei." Phytopathology 82(3): 353-357. ://A1992HG36100020 Homegrown corn samples were collected from areas with high and low rates of human esophageal cancer in the southern African territory of Transkei for six seasons over the period of 1976- 1989. The most consistent difference in the mycoflora of the corn kernels was the significantly higher incidence of Fusarium moniliforme in corn from high- vs. low-rate areas. In the 1989 samples, this significant (P < 0.01) difference in high- and low-rate cancer areas was 41.2 and 8.9%, respectively, in good (visibly nonmoldy) corn and 61.7 and 21.4%, respectively, in moldy (visibly Fusarium-infected) corn. The samples collected in 1985 and 1989 were analyzed for the presence of two secondary metabolites of F. moniliforme, the carcinogen fumonisin B1 (FB1) and its structural analogue fumonisin B2 (FB2). Significantly higher levels of both FB1 and FB2 were present in the samples from the high-rate esophageal cancer areas. Certain samples from the high-rate areas contained some of the highest levels of FB1 (up to 117,520 ng/g) and FB2 (up to 22,960 ng/g) yet recorded from naturally infected corn.

Rheeder, J. P., W. F. O. Marasas, et al. (2002). "Production of fumonisin analogs by Fusarium species." Applied and Environmental Microbiology 68(5): 2101-2105. ://000175407300002

Rheeder, J. P., E. W. Sydenham, et al. (1994). "Ear-Rot Fungi and Mycotoxins in South-African Corn of the 1989 Crop Exported to Taiwan." Mycopathologia 127(1): 35-41. ://A1994PB96200005 A shipment of South African corn (1989) exported to Taiwan, was analyzed for various ear-rot fungi and Fusarium mycotoxins. Two sets of samples, one from the points of origin in South Africa prior to shipment, and the other from the end-point distributors in Taiwan, were studied. Surface-sterilized kernels were plated onto two different agar media and the fungal colonies identified. High Performance Liquid Chromatography was used to analyze mycotoxin levels. The predominant ear-rot fungi, in decreasing order of isolation frequency, were Fusarium subglutinans, F. moniliforme, Diplodia maydis and F. graminearum. Aspergillus flavus and A. parasiticus were not isolated from samples prior to export, but a small number of A. flavus isolates were found after shipment. The predominant mycotoxins were fumonisins B-1 (0-865 ng/g) and B-2 (0-250 ng/g). Low levels of moniliformin (less than or equal to 390 ng/g) were detected in some samples before shipment. Zearalenone (25 ng/g), and nivalenol (120 ng/g) were detected in two out of 32 samples taken in Taiwan. The samples contained no detectable levels of either aflatoxins (> 0.5 ng/g) or deoxynivalenol (>100 ng/g) before or after shipment.

Richard, E., N. Heuttea, et al. (2007). "Toxigenic fungi and mycotoxins in mature corn silage." 45(12): 2420-2425. http://www.sciencedirect.com/science/article/B6T6P-4P1G9S4-1/2/912ee5d484d03f0c2e7bf7cbc5c58b95 AND http://www.botanischergarten.ch/Mycotoxins/Richard-Toxigenic-Fungi-2007.pdf To investigate the exposure of livestock and farm workers to mycotoxins during the last months of silage use, the mycoflora and the mycotoxins in a mature silage (11-months-old) were studied. A multimycotoxin method was developed to evaluate the toxigenic in vitro ability of fungal strains. The screening of potentially toxigenic fungi isolated from the mature silage showed that six Fusaria (Fusarium culmorum, Fusarium equiseti, Fusarium graminearum, Fusarium oxysporum,Fusarium solani and Fusarium verticillioides) and one Aspergillus (Aspergillus fumigatus) were able to produce mycotoxins on nutrient agar. Seven major mycotoxins (aflatoxin B1, citrinin, deoxynivalenol, fumonisin B1, gliotoxin, ochratoxin A and zearalenone) were also searched in the corn silage by high- performance liquid chromatography coupled to mass spectrometry (HPLC-MS). Among the three mycotoxins (citrinin, gliotoxin and deoxynivalenol) detected in the silage, gliotoxin, a strongly immunosuppressive mycotoxin, occured in the mature silage at level up to 877 ppb, which was associated with the presence of A. fumigatus in the silage.

Richard, J. L., D. Bhatnagar, et al. (1992). "Assessment of Aflatoxin and Cyclopiazonic Acid Production by Aspergillus-Flavus Isolates from Hungary." Mycopathologia 120(3): 183-188. ://A1992KH34300010 Thirty-two isolates of Aspergillus flavus were obtained from various sources in Hungary. All isolates were morphologically identified as A. flavus and three atypical variants were confirmed as A. flavus by comparing their DNA with an ex type culture of A. flavus. None of these isolates produced aflatoxins when tested on coconut agar or grown on rice medium and culture extracts examined by thin layer chromatography. Also, none of the isolates converted sterigmatocystin, O-methyl sterigmatocystin, norsolorinic acid, or sodium acetate to aflatoxin. However, 59% of the isolates produced cyclopiazonic acid based on thin layer chromatographic analysis of culture extracts. The isolates that lack the ability to produce both aflatoxin and cyclopiazonic acid are potential candidates for use in bicontrol studies.

Riley, R. T., E. Enongene, et al. (2001). "Sphingolipid perturbations as mechanisms for fumonisin carcinogenesis." Environmental Health Perspectives 109(2 supplement): 301-308. ://WOS:000168824500017 AND http://www.botanischergarten.ch/Bt/Riley-Sphingolipid-Perturbations-2001.pdf There is a great deal of evidence that altered sphingolipid metabolism is associated with fumonisin-induced animal diseases Including increased apoptotic and oncotic necrosis, and carcinogenesis in rodent liver and kidney. The biochemical consequences of fumonisin disruption of sphingolipid metabolism most likely to alter cell regulation are increased free sphingoid bases and their l- phosphates, alterations in complex sphingolipids, and decreased ceramide (CER) biosynthesis. Because free sphingoid bases and CER can induce cell death, the fumonisin inhibition of CER synthase can inhibit cell death induced by CER but promote free sphingoid base-induced cell death. Theoretically, at any time the balance between the intracellular concentration of effecters that protect cells from apoptosis (decreased CER, increased sphingosine 1-phosphate) and those that induce apoptosis (increased CER, free sphingoid bases, altered fatty acids) will determine the cellular response. Because the balance between the rates of apoptosis and proliferation is important in tumorigenesis, cells sensitive to the proliferative effect of decreased CER and increased sphingosine 1-phosphate may be selected to survive and proliferate when free sphingoid base concentration is not growth inhibitory. Conversely, when the increase in free sphingoid bases exceeds a cell's ability to convert sphinganine/sphingosine to dihydroceramide/CER or their sphingoid base 1-phosphate, then free sphingoid bases will accumulate. In this case cells that are sensitive to sphingoid base- induced growth arrest will die and insensitive cells will survive. If the cells selected to die are normal phenotypes and the cells selected to survive are abnormal, then cancer risk will increase.

Riley, R. T., E. Palencia, et al. (2003). "Fate of fumonisin in maize during nixtamalization and tortilla production by Mayan communities in Guatemala." Toxicological Sciences 72(1): 1227. ://000181518501232

Riley, R. T., K. A. Voss, et al. (1994). "Mechanism of Fumonisin Toxicity and Carcinogenicity - (Vol 57, Pg 638, 1994)." Journal of Food Protection 57(7): 645-645. ://A1994NZ59300017

Riley, R. T., K. A. Voss, et al. (1994). "Mechanism of Fumonisin Toxicity and Carcinogenesis." Journal of Food Protection 57(7): 638-645. ://A1994NZ59300016 what are the molecular events that fumonisin-induced porcine pulmonary edema syndrome and equine leucoencephalomalacia have in common? Do these animal diseases relate mechanistically to fumonisin toxicity in laboratory rats? There is considerable data indicating that disruption of sphingolipid metabolism plays an important early role in all of these diseases. In vitro studies have revealed that fumonisins and structurally related Alternaria alternata f. sp. lycopersici-toxin (AAL- toxin) are potent inhibitors of the enzyme sphinganine (sphingosine) N-acyl transferase (ceramide synthase). Soon after cultured cells or animals are exposed to fumonisins there is a dramatic increase in the free sphingoid base, sphinganine, in tissues, serum and/or urine. Also, free sphingosine concentration increases, complex sphingolipid concentration decreases, and sphingoid base degradation products and other lipid products also increase. It is hypothesized that disruption of sphingolipid metabolism is an early molecular event in the onset and progression of cell injury and the diseases associated with consumption of fumonisins. However, the exact mechanisms responsible for the diseases will not be easily revealed since the role of sphingolipids in cellular regulation is very complex and not yet fully understood. While fumonisin B1 is non-genotoxic it is a complete carcinogen in rat liver. Recent studies indicate that fumonisins inhibit hepatocyte proliferation in rat liver. It has been hypothesized that hepatotoxicity and effects on hepatocyte proliferation are critical determinants for fumonisin B1 cancer initiation and promotion. Alternatively, recent studies have found that fumonisin B-1 has mitogenic activity in cultured fibroblasts. It is conceivable that the mitogenic, cytostatic and cytotoxic potential of fumonisin may all contribute to the animal diseases including liver cancer in rats.

Riley, R. T., K. A. Voss, et al. (1994). "Mechanism of Fumonisin Toxicity and Carcinogenesis." Journal of Food Protection 57(6): 528-535. ://A1994NR98700015 What are the molecular events that fumonisin-induced porcine pulmonary edema syndrome and equine leucoencephalomalacia have in common? Do these animal diseases relate mechanistically to fumonisin toxicity in laboratory rats? There is considerable data indicating that disruption of sphingolipid metabolism plays an important early role in all of these diseases. In vitro studies have revealed that fumonisins and structurally related Alternaria alternata f. sp. lycopersici-toxin (AAL-toxin) are potent inhibitors of the enzyme sphinganine (sphingosine) N-acyl transferase (ceramide synthase). Soon after cultured cells or animals are exposed to fumonisins there is a dramatic increase in the free sphingoid base, sphinganine, in tissues, serum and/or urine. Also, free sphingosine concentration increases, complex sphingolipid concentration decreases, and sphingoid base degradation products and other lipid products also increase. It is hypothesized that disruption of sphingolipid metabolism is an early molecular event in the onset and progression of cell injury and the diseases associated with consumption of fumonisins. However, the exact mechanisms responsible for the diseases will not be easily revealed since the role of sphingolipids in cellular regulation is very complex and not yet fully understood. While fumonisin B1 is non-genotoxic it is a complete carcinogen in rat liver. Recent studies indicate that fumonisins inhibit hepatocyte proliferation in rat liver. It has been hypothesized that hepatotoxicity and effects on hepatocyte proliferation are critical determinants for fumonisin B1 cancer initiation and promotion. Alternatively, recent studies have found that fumonisin B1 has mitogenic activity in cultured fibroblasts. It is conceivable that the mitogenic, cytostatic and cytotoxic potential of fumonisin may all contribute to the animal diseases including liver cancer in rats.

Robens, J. (2002). "14th Aflatoxin Elimination Workshop." Mycopathologia 155(1-2): 122 pp. http://springerlink.metapress.com/content/q5236802q3312610/fulltext.pdf AND http://www.botanischergarten.ch/Bt/Robens-Aflatoxin- Fumonisin-Workshop-Phoenix-2001.pdf 14th Aflatoxin Elimination Workshop. Unlike fumonisin, which in the US is only a problem in corn, aflatoxincontaminates many crops. These include corn, peanuts, figs, cottonseed, almonds, walnuts, pistachios and otherhigh oil content crops. The first defense against aflatoxin contamination of crops is good management practices, including insectcontrol. However, in spite of good management practices, aflatoxin persists as a perennially serious problem inthe Southern US and is an episodic problem in the Midwestern US. To develop additional protection, studies areunderway using biocompetitive exclusion and conventional breeding to reduce infection with toxigenic strains ofA. flavus in figs and pistachio nuts. The biochemical mechanisms by which plant constituents increase resistanceto insect damage are being studied in corn and other crops. Identification of insect resistance genes will allowselection for resistance traits and replacement in plants where these traits have been lost. Computer programsare being developed to predict when and where fungal infection will appear in corn. Nonetheless, growers mustcarefully weigh the desire for high yield and reduced cost with the possibility of high level aflatoxin contamination.Fungi are resilient organisms. The goal of complete elimination of aflatoxin will be difficult to attain. Understandingthe physiological and environmental factors that control the interactions between fungi and between thefungus and its host is critical. This has led to successful use of competitive exclusion to control preharvest aflatoxincontamination of cottonseed in Arizona. In 2001, nearly 20,000 acres of Arizona cotton fields were treated with theatoxigenic biocontrol strain AF36. The level of aflatoxin in cottonseed was reduced by 80% compared to untreatedfields. This approach is also proving successful for cotton in South Texas, and is now being explored for corn andpeanuts and has promise for pistachio nuts and figs. The use of other biocontrol agents such as saprophytic yeast isalso being shown to be effective against colonization by toxigenic fungi in almond and pistachio.Breeding for resistance has the most promise for long-term, effective control. However, in addition to lowerlevels of aflatoxin, the variety must have agronomic traits that are attractive to the grower. Considerable success hasbeen achieved in developing acceptable almond varieties with resistance to both insect damage and aflatoxin contamination. Similar success is being achieved in identifying resistant peanut genotypes with favorable agronomiccharacteristics. Success in corn has been more difficult since multiple mechanisms of resistance are necessaryto achieve reduced levels of aflatoxin contamination. There is an ongoing concerted effort to identify resistantgermplasm, mechanisms of resistance, and molecular markers for resistance that can facilitate development ofcorn varieties with desirable agronomic traits. Identification of the natural sources of resistance in commerciallyacceptable varieties is a critical first step to the development of resistant varieties acceptable to growers. Progresshas been made in identifying natural constituents of walnut, endogenous enzymes and other proteins in maize, plantgrowth regulators, and volatile hydrocarbons emitted by pistachio leaves that act as aflatoxin resistance factors,inhibit toxin biosynthesis, or have antifungal properties. These sources of resistance will be useful for developingmolecular markers to be used in conventional breeding and with transgenic approaches for reducing aflatoxin incrops. Identification of the factors controlling toxin production and fungal infection, and a better understanding ofthe molecular basis for plant resistance are crucial first steps towards development of transgenic varieties resistantto aflatoxin contamination. Crop resistance to aflatoxin through genetic engineering remains largely in the developmentphase. Genes have been identified that produce proteins that are toxic to invading fungi, however, theexpression of these peptides in plants is difficult to monitor and often lack efficacy at target sites. As with conventionalbreeding approaches, development of transgenic varieties will require introduction of multiple mechanismsof resistance to achieve reduced levels of aflatoxin contamination.The sponsors of all three 2001 workshops in Phoenix were the National Cotton Council, the National CottonseedProducts Association, the Cotton Foundation, Cotton Incorporated, and the Arizona Cotton Research andProtection Council. USDA-ARS sponsored research to resolve the problem of aflatoxin contamination of cottonseedhas met with many successes. This year’s workshop featured a site visit to the Arizona Cotton Research andProtection Council Facility in Phoenix. This facility is undoubtedly the best example of what can be accomplishedthrough well funded collaborative research efforts between ARS, industry and university scientists.

Romeis, J. and F. Bigler (2004). "Proceedings of the Meeting “Ecological Impact of Genetically Modified Organisms” at Prague (Czech Republic), ." IOBC wprs Bulletin 29(5): xx + 215. http://www.botanischergarten.ch/Bt/Romeis-IOBC-Bulletin-2006.pdf Plant transformation: methodology, applications and the potential for unintended effects. A.M.R. Gatehouse ...... 1 Molecular solutions for increasing biosafety of transgenic plants. J. Gressel & H. Al-Ahmad...... 7 Testing rubidium marking for measuring adult dispersal of the corn borer Sesamia nonagrioides: first results. R. Albajes, J. Eras, C. López, X. Ferran, J. Vigatà & M. Eizaguirre...... 15 Analysis of web content of Theridion impressum L. Koch (Araneae: Theridiidae) in BT (DK 440 BTY, MON 810, Cry1Ab) and isogenic (DK 440) maize. K. Árpás, F. Tóth & J. Kiss...... 23 Impact of transgenic oilseed rape on soil arthropod assemblages. G. Burgio, F. Ramilli, M.C. Fiore & F. Cellini...... 31 Potential effect of GNA-transgenic potatoes on adult aphid parasitoids. A. Couty & J. Romeis...... 37 Monitoring of pest and beneficial insect populations in summer sown Bt maize. G. Delrio, M. Verdinelli & G. Serra...... 43 Assessing expression of Bt-toxin (Cry1Ab) in transgenic maize under different environmental conditions. A. Dutton, M. D’Alessandro, J. Romeis & F. Bigler...... 49 Tracking Bt-toxin in transgenic maize to assess the risks on non-target arthropods. A. Dutton, L. Obrist, M. D’Alessandro, L. Diener, M. Müller, J. Romeis & F. Bigler...... 57 Comparison of the nodulation ability and abundance of aerobic bacteria in the rhizosphere of transgenic and non-transgenic lines of alfalfa. N. Faragová, J. Faragó & J. Gálová...... 65 Research programme to monitor corn borer resistance to Bt-maize in Spain. G.P. Farinós, M. De La Poza, M. González-Núñez, P. Hernández-Crespo, F. Ortego & P. Castañera...... 73 Results of a 4-year plant survey and pitfall trapping in Bt maize and conventional maize fields regarding the occurrence of selected arthropod taxa. B. Freier, M. Schorling, M. Traugott, A. Juen & C. Volkmar...... 79 Population development of some predatory insects on Bt and non-Bt maize hybrids in Turkey. M. Güllü, F. Tatli, A.D. Kanat & M. İslamoğlu...... 85 The GMO Guidelines Project and a new ecological risk assessment. A. Hilbeck, D. Andow & E. Underwood...... 93 European corn borer (Ostrinia nubilalis): Studies on proteinase activity and proteolytical processing of the B.t.-toxin Cry1Ab in transgenic corn. R. Kaiser-Alexnat, W. Wagner, G.-A. Langenbruch, R.G. Kleespies, B. Keller & B. Hommel...... 97 First investigations on the effects of Bt-transgenic Brassica napus L. on the trophic structure of the nematofauna. B. Manachini, S. Landi, M.C. Fiore, M. Festa & S. Arpaia...... 103 Studies on the effects of Bt corn expressing CryIAb on two parasitoids of Ostrinia nubilalis Hb. (Lepidoptera: Crambidae). B. Manachini & G.C. Lozzia...... 109 Implications for the parasitoid Campoletis sonorensis (Hymenoptera: Ichneumonidae) when developing in Bt maize-fed Spodoptera littoralis larvae (Lepidoptera: Noctuidae). M. Meissle, E. Vojtech & G.M. Poppy...... 117 Production of Cry1Ab toxin in E. coli for standardisation of insect bioassays. Nguyen Thu Hang, T. Meise, G.-A. Langenbruch & J.A. Jehle...... 125 No effects of Bt maize on the development of Orius majusculus. X. Pons, B. Lumbierres, C. López & R. Albajes...... 131 Impact of growing Bt-maize on cicadas: Diversity, abundance and methods. S. Rauschen, J. Eckert, A. Gathmann & I. Schuphan...... 137 Impact of genetically modified herbicide resistant maize on the arthropod fauna. I.I. Rosca...... 143 A biannual study on the environmental impact of Bt maize. F. Sehnal, O. Habuštová, L. Spitzer, H.M. Hussein & V. Růžička...... 147 Determination of fungi species, relationship between ear infection rates and fumonisin quantities in Bt maize. F. Tatli, M. Güllü & F. Ozdemir...... 161 Spider communities in Bt maize and conventional maize fields. C. Volkmar, M. Traugott, A. Juen, M. Schorling & B. Freier...... 165 Larvicidal activities of transgenic Escherichia coli against susceptible and Bacillus thuringiensis israelensis-resistant strains of Culex quinquefasciatus. M.C. Wirth, W.E. Walton, R. Manasherob, V. Khasdan, E. Ben-Dov, S. Boussiba & A. Zaritsky...... 171 Peculiarities of Cry proteins to be taken into account during their in vivo and in vitro study. I.A. Zalunin, L.P. Revina, L.I. Kostina & G.G. Chestukhina ...... 177

Roscoe, V., G. A. Lombaert, et al. (2008). "Mycotoxins in breakfast cereals from the Canadian retail market: A 3-year survey." Food Additives and Contaminants 25(3): 347-355. ://WOS:000253660000012 One hundred and fifty-six samples of breakfast cereals were collected from the Canadian retail marketplace over a 3-year period. The samples were analysed for the mycotoxins deoxynivalenol, nivalenol, HT-2 toxin, zearalenone, ochratoxin A, and fumonisins B1 and B2 to contribute to dietary exposure estimates in support of the development of Canadian guidelines for selected mycotoxins in foods. The samples included corn-, oat-, wheat- and rice-based cereals, as well as mixed-grain cereals, and were primarily from North American processors. Overall, deoxynivalenol was the most frequently detected mycotoxin - it was detected in over 40% of all samples analysed. Fumonisins and ochratoxin A were each detected in over 30% of all samples. Zearalenone was detected in over 20% of all samples. Nivalenol and HT-2 toxin were each detected in only one sample. The survey clearly demonstrated regular occurrence of low levels of multiple mycotoxins in breakfast cereals on the Canadian market.

Rossi, F., M. Morlacchini, et al. (2005). "Effect of Bt corn on broiler growth performance and fate of feed-derived DNA in the digestive tract." Poultry Science 84(7): 1022-1030. ://000230047700007 AND http://www.botanischergarten.ch/Bt/Rossi-Effect-Broilers-2005.pdf The aim of the study was to evaluate the effect on broiler performance of transgenic Bacillus thuringiensis (Bt) corn containing the Cry1A(b) protein compared with the corresponding near isogenic corn and to analyze the degradation of the CryIA(b) gene in the digestive tract. Ross male broilers (432) were fed for 42 consecutive days with diets containing Bt or isogenic corn. Diet, Bt corn, and the isogenic form of the Bt corn were analyzed for composition and aflatoxin B-1, fumonisin B-1, and deoxynivalenol contents. Broiler body weight and feed intake were recorded at regular intervals (d 0, 21, and 42). The presence of the CryIA(b) gene and plant-specific genes Zein and Sh-2 in gut contents of crop, gizzard, jejunum, cecum, and samples of blood was determined in 10 animals per treatment at the end of the trial using a PCR technique. Chemical composition was not different between Bt and its isogenic form, whereas the fumonisin B, content for Bt was lower than for isogenic corn (2,039 vs. 1,1034 ppb; P < 0.05). The results of the growth study showed no difference for average daily weight gain (129.4 vs. 126.0 g/d), feed intake (63.4 vs. 61.8 g/d), and feed conversion ratio (1.95 vs. 2.02) among the groups. No significant relationship was observed between mycotoxins content and growth performances. Feed-derived DNA is progressively degraded along the digestive tract. Detection frequency of short fragments of maize-specific high copy number Zein gene was high but significantly decreased in distal sectors. An 1,800-bp fragment of the Cry1A(b) gene, corresponding to the minimal functional unit, was detected only in crop and gizzard of birds fed Bt corn. Sh-2 showed the same detection frequency of CryIA(b) and was also found in birds fed isogenic corn. Blood samples were positive with low frequency only for the Zein gene fragment. No significant difference in DNA detection was observed between birds fed Bt and isogenic corn, indicating that DNA derived from transgenic feed undergoes the same fate as isogenic feed.

Roy, A. K. and H. K. Chourasia (1990). "Mycoflora, Mycotoxin Producibility and Mycotoxins in Traditional Herbal Drugs from India." Journal of General and Applied Microbiology 36(5): 295-302. ://A1990EZ70400001

Ryu, D., C. Munimbazi, et al. (1999). "Fumonisin B-1 production by Fusarium moniliforme and Fusarium proliferatum as affected by cycling temperatures." Journal of Food Protection 62(12): 1456-1460. ://000084146300014 The effects of temperatures cycling between 5 and 20 degrees C, 10 and 25 degrees C, and 15 and 30 degrees C on the production of fumonisin B-1 (FB1) and ergosterol by Fusarium moniliforme and Fusarium proliferatum on rice was studied. Temperatures were cycled at 12-h intervals by manually moving cultures from one temperature to another. Constant temperature incubation at 25 degrees C and a low temperature stress were compared with the cycling temperature incubations. Low temperature stress was achieved by incubating rice cultures at 25 degrees C for 2 weeks followed by 15 degrees C for 4 weeks. The maximum yields of FB1 were found to be 247 mu g/g by F. moniliforme at temperatures that cycled between 10 and 25 degrees C after 2 weeks and 284 mu g/g by F. proliferatum when the temperatures cycled between 5 and 20 degrees C after 6 weeks. Ergosterol content of the rice cultures was also monitored. Overall, the two Fusarium species showed differences in production of FB1 and ergosterol under the various temperature treatments. The most notable differences were that the temperature treatments that stimulated greatest FB1 production were different for each species: cycling temperatures between 10 and 25 degrees C for F, moniliforme and cycling temperatures between 5 and 25 degrees C for F. proliferatum. At most temperatures, F proliferatum produced more ergosterol than F, moniliforme. Maximum production of ergosterol by F. proliferatum occurred at 6 weeks, with temperatures that cycled between 10 and 25 degrees C, whereas F. moniliforme produced maximum amounts of ergosterol at 6 weeks, with temperatures that cycled between 15 and 30 degrees C.

Ryu, J. C., J. S. Yang, et al. (1996). "Survey of natural occurrence of trichothecene mycotoxins and zearalenone in Korean cereals harvested in 1992 using gas chromatography mass spectrometry." Food Additives and Contaminants 13(3): 333-341. ://A1996UH52900009

Saunders, D. S., F. I. Meredith, et al. (2001). "Control of fumonisin: Effects of processing." Environmental Health Perspectives 109(2 supplement): 333-336. ://WOS:000168824500022 AND http://www.botanischergarten.ch/Bt/Saunders-Control-Fumonisin-2001.pdf Of about 10 billion bushels of corn that are grown each year in the United States, less than 2% is processed directly into food products, and about 18% is processed into intermediates such as high-fructose corn syrup, ethanol, and cornstarch. The vast majority of the annual crop is used domestically for animal feed (60%), and about 16% is exported. Thus, any program for controlling residues of fumonisin (FB) in food must recognize that most of the crop is grown for something other than food. Studies on the effects of wet milling on FR residues found these residues nondetectable in cornstarch, the starting material for hi(high-fructose corn syrup and most other wet-milled food ingredients. Similar effects are noted for the dry-milling process. FB residues were nondetectable or quite low in dry flaking grits and corn flour, higher in corn germ, and highest in corn bran. Extrusion of dry-milled products reduces FB concentrations by 30-90% for mixing-type extruders and 20-50% for nonmixing extruders. Cooking and canning generally have little effect on FB content. In the masa process measurable FB is reduced following the cooking, soaking, and washing steps, with little conversion of FB to the hydrolyzed form. Sheeting, baking, and frying at commercial times and temperatures generally have no effect. In summary, all available studies on the effects of processing corn into food and food ingredients consistently demonstrate substantial reductions in measurable FB. No studies have shown a concentration in FB residues in food products or ingredients.

Saxena, J., C. Munimbazi, et al. (2001). "Relationship of mould count, ergosterol and ochratoxin A production." International Journal of Food Microbiology 71(1): 29-34. ://000172559600003 The relationship between viable mould count, ergosterol content and ochratoxin A (OA) formation was studied at different inoculum concentrations of Aspergillus ochraceus NRRL 3174 and Penicillium verrucosum NRRL 3260 own on sterile long-grain enriched white rice as the substrate. Ergosterol was determined by extraction, saponification and quantification using hi.-h performance thin layer chromatography (HPTLC) with UV detection. Ergosterol and ochratoxin A were detected after 3 days of incubation and reached their maximum at 7-10 days of incubation. After that, a decline in the concentrations in both ergosterol and ochratoxin was observed. Ergosterol measurement by HPTLC appeared to be a useful method to detect fungal activity, which corresponded to ochratoxin production. Thus, the ergosterol assay may have a use as an early indicator of potential mycotoxin production. (C) 2001 Elsevier Science B.V. All rights reserved.

Schaafsma, A. W., D. C. Hooker, et al. (2002). "Effect of Bt-corn hybrids on deoxynivalenol content in grain at harvest." Plant Disease 86(10): 1123-1126. ://000178170300011 Concentrations of the Mycotoxins deoxynivalenol (DON) and fumonisin B-1 in grain were compared among Bt-transformed corn hybrids and their non-Bt isolines on 102 commercial corn Fields across Ontario from 1996 to 1999. Intensities of naturally occurring populations of Ostrinia nubilalis were assessed from tunneling measurements in the stalks of non-Bt isolines in 1996 and 1997. Mean concentrations of fumonisin B-1 across hybrids were <0.25 μg g(-1) in every year of the study. Relationships between the concentration of fumonisin B, and intensity of O. nubiledis or with the use of Bt corn hybrids could not be determined because the concentrations of fumonisin B-1 were below the lower limit of detection in most fields (<0.1 mug g(-1)). However, DON was more prevalent with mean concentrations across fields from 0.42 mug g(-1) in 1997 to 1.12 mug g(-1) in 1999, The effect of Bt hybrids on reducing concentrations of DON was mainly dependent on the intensity of O. nubilalis in each field. Where a high intensity (stalk injury) of O. nubilalis was observed (>4 cm of tunnel per stalk in the non-Bt), the use of Bt hybrids reduced concentrations of DON by an average of 59% from concentrations in the non-Bt isoline. Where the intensity of O. nubilalis was low (<4 cm of tunneling per stalk), concentrations of DON were not different among Bt and non-Bt hybrids. Concentrations of DON were low and not different between events Bt11 and 176 among Bt hybrids. A quadratic relationship was developed showing that the concentration of DON increased with intensity of O. nubilalis feeding. This study cautiously supports the use of Bt corn to reduce the risk of high concentrations of DON at harvest in Ontario.

Schlechter, M., W. F. O. Marasas, et al. (1998). "Incidence of Fusarium moniliforme and fumonisins in commercial maize products, intended for human consumption, obtained from retail outlets in the United States and South Africa." South African Journal of Science 94(4): 185-187. ://000074457000033 Fusarium moniliforme is associated with ear-rot of maize worldwide and is regarded as the most common seed-borne fungus of maize in South Africa. Fumonisins B-1 and B-2 secondary metabolites produced by F. moniliforme, cause acute toxic effects in several animal species, and are associated with a high risk of oesophageal cancer in humans who consume contaminated home- grown maize. Various commercial maize products intended for human consumption were purchased from several retail supermarkets in the US and South Africa, and subjected to mycological and chemical analyses. Fungal counts for F. moniliforme and the levels of fumonisin contamination were generally higher in the American maize products. The mean levels off moniliforme contamination in the South African and US products were 19 x 10(2) and 1037 x 10(2) cfu g(-1), respectively. Total fumonisin levels ranged from 0-465 ng g(-1) and from 0-3605 ng g(-1), respectively 'Braaipap' meals contained the highest mean fumonisin levels amongst the South African products (FB1, 177 ng g(-1); FB2, 32 ng g(-1)), whereas the American products with the most contamination were the white meals (FB1, 1365 ng g(-1); FB2, 319 ng g(-1)).

Schothorst, R. C. and H. P. van Egmond (2004). "Report from SCOOP task 3.2.10 "collection of occurrence data of Fusarium toxins in food and assessment of dietary intake by the population of EU member states" - Subtask: trichothecenes." Toxicology Letters 153(1): 133-143. ://WOS:000224154300015 AND http://www.botanischergarten.ch/Bt/Schothorst-Report-SCOOP-Fusarium-EU-2004.pdf In 2001 the SCOOP (SCOOP: Scientific Co-operation on Questions relating to Food) task 3.2.10 "Collection of occurrence data of Fusarium toxins in food and assessment of dietary intake by the population of EU Member States" was established. The task was divided in three subtasks (zearalenone, fumonisins and trichothecenes). Results of the subtask trichothecenes, which is co-ordinated by The Netherlands, will be presented. About 35,000 results were received about occurrence of 12 different trichothecenes (deoxynivalenol (DON), nivalenol (NIV), 3 and 15 acetyl-deoxynivalenol (3/15-AcDON), fusarenon-X (FUS-X), T-2 and HT-2 toxin, T2- triol, diacetoxyscirpenot (DAS), neosolaniol (NEOSOL, monoacetoxyscirpenol (MAS) and verrucarol (VOL)) in various food and food raw materials from 12 countries. Only the results of DON, NIV, T-2 and HT-2 toxin are included in this paper, because most of the data refer to these toxins and only for these trichothecenes the Scientific Committee for Food sets (temporary)-Tolerable Daily Intakes (t-TDIs). Occurrence data: By far most of the occurrence data were obtained for DON in wheat. Among cereals, corn showed the highest level of contamination with trichothecenes. Consumption data: There is a significant lack of consumption data in some countries. In particular information on baby's and children's food is generally not available. Intake data: Wheat and wheat containing products (like bread and pasta) represent the major source of intake for the four trichothecenes. The mean intakes for DON are below the TDI, however for the young children groups the mean intakes are sometimes (very) close to the TDI. By comparing the high intake levels for DON with the TDI, it is clear that especially for the young children groups most of the intakes are above the TDI. For NIV, the (mean and high level) intakes are far below the TDI. The summarised T-2 and HT-2 toxin intakes are in most cases (for the mean as well as the high level intake) above the t-TDI. (C) 2004 ILSI. Published by Elsevier Ireland Ltd. All rights reserved.

Schuhmacher, R., R. Krska, et al. (1997). "Interlaboratory comparison study for the determination of the Fusarium mycotoxins deoxynivalenol in wheat and zearalenone in maize using different methods." Fresenius Journal of Analytical Chemistry 359(6): 510-515. ://A1997YJ05900008

Scott, P. M. (1968). "Note on Analysis of Aflatoxins in Green Coffee." Journal of the Association of Official Analytical Chemists 51(3): 609-&. ://WOS:A1968B181600028

Scott, P. M. (1969). "Analysis of Cocoa Beans for Aflatoxins." Journal of the Association of Official Analytical Chemists 52(1): 72-&. ://WOS:A1969C496600015

Scott, P. M. (1973). "Modified Method for Determination of Mycotoxins in Cocoa Beans." Journal of the Association of Official Analytical Chemists 56(4): 1028-1030. ://WOS:A1973Q387300051

Scott, P. M. (1978). "Mycotoxins in Feeds and Ingredients and Their Origin." Journal of Food Protection 41(5): 385-398. ://WOS:A1978FA10400014

Scott, P. M. (1984). "Citation Classic - Mycotoxins (Ochratoxin-a, Citrinin, and Sterigmatocystin) and Toxigenic Fungi in Grains and Other Agricultural Products." Current Contents/Agriculture Biology & Environmental Sciences(20): 16-16. ://WOS:A1984SP74900001

Scott, P. M. (1984). "Effects of Food-Processing on Mycotoxins." Journal of Food Protection 47(6): 489-499. ://WOS:A1984SW71000015

Scott, P. M. (1984). "Report on Mycotoxins." Journal of the Association of Official Analytical Chemists 67(2): 366-369. ://WOS:A1984SN25900059

Scott, P. M. (1985). "Report on Mycotoxins." Journal of the Association of Official Analytical Chemists 68(2): 242-248. ://WOS:A1985AEK5600043

Scott, P. M. (1986). "Mycotoxins." Journal of the Association of Official Analytical Chemists 69(2): 240-246. ://WOS:A1986A476600032

Scott, P. M. (1987). "Mycotoxins." Journal of the Association of Official Analytical Chemists 70(2): 276-281. ://WOS:A1987G660000035

Scott, P. M. (1988). "Mycotoxins." Journal of the Association of Official Analytical Chemists 71(1): 70-76. ://WOS:A1988M028900040

Scott, P. M. (1989). "Methods for Determination of Aflatoxin-M1 in Milk and Milk-Products - a Review of Performance-Characteristics." Food Additives and Contaminants 6(3): 283-305. ://WOS:A1989U457600002

Scott, P. M. (1989). "Mycotoxins." Journal of the Association of Official Analytical Chemists 72(1): 75-80. ://WOS:A1989T353600038

Scott, P. M. (1991). "Mycotoxins." Journal of the Association of Official Analytical Chemists 74(1): 120-128. ://WOS:A1991EV85600033

Scott, P. M. (1992). "Mycotoxins." Journal of Aoac International 75(1): 95-102. ://WOS:A1992HK10700036

Scott, P. M. (1993). "Fumonisins." International Journal of Food Microbiology 18(4): 257-270. ://WOS:A1993LH90500003 Fusarium moniliforme Sheldon is a common fungal contaminant of corn and produces a variety of mycotoxins. Among these are the recently discovered fumonisins, which are now known to cause certain animal diseases, namely leukoencephalomalacia in horses and pulmonary edema in swine. There is a significant association between their presence in corn and human esophageal cancer in southern Africa. Fumonisin B1 causes liver cancer in rats. Five other fumonisins-B2, B3, B4, A1 and A2, have been isolated; the last two are N-acetates of fumonisins B1 and B2 and do not appear to be toxic. Several other Fusarium species are now known to produce fumonisins. Procedures for detection and determination of fumonisins include thin layer chromatography, liquid chromatography (with fluorescence derivatization), post-hydrolysis gas chromatography, immunochemical assay, and mass spectrometry. In addition to their natural occurrence in corn-based animal feeds and in home-grown African corn used for food, fumonisins are frequently found in commercial corn-based foods. Fumonisins are moderately heat-stable. No effective detoxification process has yet been developed for use with fumonisin-contaminated feeds.

Scott, P. M. (1993). "Mycotoxins." Journal of Aoac International 76(1): 112-119. ://WOS:A1993KG91100037

Scott, P. M. (1993). "Recent Developments in Methods of Analysis for Mycotoxins in Foodstuffs." Trac-Trends in Analytical Chemistry 12(9): 373-381. ://WOS:A1993MC94500005 New techniques and trends relating to mycotoxin methodology are reviewed, with emphasis on the procedures comprising an analytical method for foodstuffs - sampling, extraction of naturally contaminated samples, cleanup (in particular solid phase extraction and immunoaffinity columns), detection and determination, and confirmation. Also covered are automation and some aspects of assessing analyst performance. The aflatoxins (including aflatoxin M1), ochratoxin A, trichothecenes, zearalenone, and patulin are among the mycotoxins used to exemplify recent method development.

Scott, P. M. (1995). "Mycotoxin Methodology." Food Additives and Contaminants 12(3): 395-403. ://WOS:A1995RC65700016 Sensitive, specific, accurate and precise methods of analysis are needed for enforcement of mycotoxin regulations, other monitoring programmes, and research studies. Rapid screening tests are useful fdr control at all stages of food and feed production. There is a wide choice of both quantitative and qualitative methods for the more well known mycotoxins. Those at present covered by method standardization organizations such as AOAC International are aflatoxins (including Mi), Alternaria toxins, citrinin, cyclopiazonic acid, ergot alkaloids, fumonisins, ochratoxins, patulin, trichothecenes, and zearalenone. Methodology for mycotoxins is selectively reviewed in this paper with emphasis on the procedures comprising the analytical method-sampling, extraction of naturally contaminated samples, clean-up, detection and determination, and confirmation. Also covered are automation, method comparison, and method assessment.

Scott, P. M. (1996). "Mycotoxins transmitted into beer from contaminated grains during brewing." Journal of Aoac International 79(4): 875-882. ://WOS:A1996UX85300013 Studies with aflatoxin B-1, ochratoxin A, zearalenone, deoxynivalenol, and fumonisins B-1 and B-2 added at various stages of the brewing process show that these mycotoxins (or metabolites) may be transmitted from contaminated grains into beer, Citrinin does not survive the mashing step, Mycotoxins in beer could originate from the malted grain or from adjuncts, Although high incidences and concentrations of aflatoxins and zearalenone have been found in local beers brewed in Africa, aflatoxins have not been detected in European beers, Zearalenone and alpha- or beta-zearalenol (the metabolite likely to occur) have not been found in Canadian and European beers, except for one sample analyzed by thin-layer chromatography only, Ochratoxin A rarely has been detected at >1 ng/mL in beer; liquid chromatographic methods with a 0.05-0.1 ng/mL detection limit, however, have shown moderately high incidences of trace levels, Deoxynivalenol, which survives the brewing process, has been found with high incidence in Canadian and European beers, with concentrations of >200 ng/mL reported in several German beers, Fumonisins B-1 and B-2 occur to a limited extent in beer.

Scott, P. M. (1998). "Chromatography of mycotoxins - Foreword." Journal of Chromatography A 815(1): 1-1. ://WOS:000075254200001

Scott, P. M. (1998). "Industrial and farm detoxification processes for mycotoxins." Revue De Medecine Veterinaire 149(6): 543-548. ://WOS:000075078200006 Treatments that destroy or inactivate mycotoxins, and the effects of food and feed processing on mycotoxin concentrations and distribution are selectively reviewed. Requirements for technologically and economically feasible decontamination processes are outlined. Physical and chemical methods for decontamination of commodities containing mycotoxins that are used in practice (out of numerous experimentally successful procedures) include segregation and sorting of aflatoxin-containing peanuts; addition of adsorbents (sequestrants) to animal feed; and ammoniation of peanut meal, cottonseed, cottonseed meal and corn. Although some normal food and feed processing operations such as heat treatments can partly destroy certain mycotoxins, it is important to note that other processes can cause increases in mycotoxin concentrations in products such as malted barley, bran, corn germ, and spent grains from fermentation.

Scott, P. M. (2001). "Analysis of agricultural commodities and foods for Alternaria mycotoxins." Journal of Aoac International 84(6): 1809-1817. ://WOS:000172489900022 Fungi of the genus Alternaria are parasitic on plants and other organic materials. A. alternata is a frequently occurring species of particular interest because it produces a number of mycotoxins, including alternariol (AOH), alternariol monomethyl ether (AME), altenuene (ALT), altertoxins I, II, and III (ATX-I, -II, and -III), and L-tenuazonic acid (TeA). Cleanup procedures of analytical methods for foods and foodstuffs include solvent partition, generally used for TeA, and solid-phase extraction columns for AOH, AME, and ATX-I. These Alternaria mycotoxins have been determined by TLC, GC, and more usually LC, mainly with ultraviolet detection, although fluorescence and electrochemical detection have also been used for Alternaria toxins other than TeA. A Zn2+ salt is usually added to the LC mobile phase for TeA. Recently, atmospheric pressure chemical ionization and electrospray LC/MS and LC-MS/MS have been applied to the determination and confirmation of AOH and AME in apple juice and other fruit beverages at sub ng/mL levels. Natural occurrences of AOH, AME, and in some cases other Alternaria toxins have been reported in various fruits, including tomatoes, olives, mandarins, melons, peppers, apples, and raspberries. They have been found also in processed fruit products such as apple juice, other fruit beverages and tomato products, wheat and other grains, sunflower seeds, oilseed rape meal, and pecans.

Scott, P. M., T. Delgado, et al. (1994). "Determination of Fumonisins in Milk." Journal of Environmental Science and Health Part B-Pesticides Food Contaminants and Agricultural Wastes 29(5): 989-998. ://WOS:A1994PB62600007 Fumonisin B-1 (FB1) and fumonisin B-2 (FB2) were determined in milk by liquid chromatography (LC) following immunoaffinity column cleanup. Recoveries from milk spiked with 5-50 ng each fumonisin/ml averaged 79-109%. The aminopentol hydrolysis product of FB1 (AP(1)) was determined by LC after cleanup on a C-18 solid phase phase extraction column; mean recoveries were 69-83% at spiking levels of 50-100 ng AP(1)/ml milk. Detection limits were of the order 3-7 ng/ml for FB1 and FB2, and 20-25 ng/ml for AP(1). A stability study showed no losses of FB1 and FB2 in milk under conditions of freezing, refrigeration and boiling. A transmission study using four cows dosed with pure FB1 either orally (1.0 and 5.0 mg FB1/kg b.w.) or by i.v. injection (0.05 and 0.20 mg FB1/kg b.w.) showed no detectable residues of FB1 or AP(1) in the milk, with or without hydrolytic treatment with beta- glucuronidase/sulfatase to liberate any conjugates.

Scott, P. M., S. R. Kanhere, et al. (1995). "Fermentation of Wort Containing Added Ochratoxin-a and Fumonisin-B-1 and B-2." Food Additives and Contaminants 12(1): 31-40. ://WOS:A1995QL74900004 Ochratoxin A (OA), fumonisin B-1 (FB1) and fumonisin B-2 (FB2) were added to wort at levels of 0.19, 0.95 and 0.95 mu g/ml, respectively, and fermented for up to 8 days by three strains of Saccharomyces cerevisiae. Decreases of OA in the beer over this period were estimated from straight line slopes to be 2-13%. Losses of FB1 and FB2 were estimated to be 3-28% and 9-17% respectively. Some OA was taken up by the yeast, up to 21% in a detailed study with one strain. In contrast, uptake of fumonisins by yeast was negligible (< 1% FB1 and < 2% FB2). In control experiments, OA, FB1 and FB2 were found to be stable when added to yeast-free wort and kept for up to 8 days at 25 degrees C. In addition, spiking experiments with blank day 0-8 fermenting wort samples showed method recoveries averaging 87-91%. None of the mycotoxins was detected in control fermentations where they were not added to the wort.

Scott, P. M., S. R. Kanhere, et al. (1993). "Analysis of Canadian and Imported Beers for Fusarium Mycotoxins by Gas-Chromatography Mass- Spectrometry." Food Additives and Contaminants 10(4): 381-389. ://WOS:A1993LR56000002 A sensitive method was developed for the determination of deoxynivalenol (DON), nivalenol (NIV), alpha-zearalenol (alpha-ZEL), beta-zearalenol (beta-ZEL) and zearalenone (ZEN) in beer by capillary gas chromatography-mass spectrometry (GC-MS) of their heptafluorobutyrate (HFB) derivatives. Recoveries averaging 90-103% were obtained from beers spiked with each mycotoxin in the 5-20 ng/ml concentration range. Limits of detection were 0.1-1.5 ng DON/ml, 0.01-0.3 ng NIV/ml, 2.5-3 ng alpha- and beta-ZEL/ml, and 1.5-2 ng ZEN/ml. Twenty-nine of 50 samples of Canadian and imported beer surveyed were found to contain DON; of these nine contained greater than 5 ng/ml (up to 50 ng/ml). The identity of DON was confirmed by response ratios at m/z 670 and m/z 884 for the HFB derivative and m/z 497 and m/z 512 for the trimethylsilyl (TMS) derivative. NIV was also detected in three beer samples (0.1-0.84 ng/ml) but no alpha-ZEL, beta-ZEL or ZEN was found

Scott, P. M. and G. A. Lawrence (1992). "Liquid-Chromatographic Determination of Fumonisins with 4-Fluoro-7-Nitrobenzofurazan." Journal of Aoac International 75(5): 829-834. ://WOS:A1992JQ07600014 Fumonisins B1 and B2 are closely related mycotoxins produced by Fusarium moniliforme, F. proliferatum, and related species. Disadvantages of 2 fluorescence derivatizing reagents currently used for liquid chromatography (LC) are instability of the derivatives (with o-phthaldialdehyde-mercaptoethanol) and formation of 2 peaks (with fluorescamine). 4-Fluoro-7-nitrobenzofurazan (4-fluoro- 7-nitrobenz-2-oxa-1,2-diazole; NBD-F) was, therefore, investigated. Although a larger molar excess of this reagent is required for fumonisins than for amino acids, the derivatives formed are moderately stable, and as little as 1 ng fumonisins B1 or B2 can be detected, with a linear response up to at least 50 ng injected. Reversed-phase LC (C18 column) was carried out with a mobile phase of methanol-0.05M sodium dihydrogen phosphate adjusted to pH 5 (1 + 1), which was mixed with an equal volume of acetonitrile- water (8 + 2) after 5 min. Using a modification of a strong anion exchange cleanup procedure, good recoveries (averages of 94 and 80%, respectively) of fumonisins B1 and B2 from ground com, corn meal, and com flakes in the 125-5000 ng/g range were generally obtained; the limit of detection of the overall method was about 100 ng/g. Similar results were obtained in studies with ground corn, com meal, and com flakes using naphthalene-2,3-dicarboxaldehyde-potassium cyanide (NDA-KCN) for derivatization; average recoveries of fumonisins B1 and B2 Were 94 and 83%, respectively.

Scott, P. M. and G. A. Lawrence (1994). "Stability and Problems in Recovery of Fumonisins Added to Corn-Based Foods." Journal of Aoac International 77(2): 541-545. ://WOS:A1994NF07800040 Because the natural occurrence of fumonisins is so far known almost exclusively in corn, we have limited our investigations on their stability to corn-based foods. In these studies, distinction must be made between real losses, binding, and any matrix-related method problems. Fumonisins B-1 (FB1) and B-2 (FB2) were about 40% recovered when heated in corn meal at 190 degrees C, about 20-30% recovered when heated in moist corn meal at 190 degrees C, and completely unstable in corn meal at 220 degrees C. Average recoveries of FB1 and FB2 added to blank heated matrixes were 69-107% in control experiments. Baking corn meal muffins spiked with 2.5 mu g FB1 and FB2/g corn meal at 220 degrees C also resulted in losses of fumonisins. Little or no fumonisins were recovered from corn bran flour when methanol-water (3 + 1) was used as extraction solvent. However, when methanol-borate buffer (pH 9.2) (3 + 1)was used, recoveries averaged 91 +/- 17 and 84 +/- 9%, respectively, for FB1 and FB2; and natural contamination of the corn bran flour with FB1 and FB2 at levels of 1.9 and 0.95 mu g/g, respectively, was revealed. Comparable recoveries were observed for 1 brand of a corn bran breakfast cereal, but the binding effect was not seen with a second brand, for which methanol-water (3 + 1)alone was a good extraction solvent. Recoveries of FB1 and FB2 from a mixed cereal for babies were only about 50% with either extraction solvent mixture. Additives present in the mixed cereal-calcium carbonate, dibasic calcium phosphate, and reduced iron (iron filings)-did not affect recoveries of FB1 and FB2 when added to ground corn or corn flakes, although hydrated ferrous sulfate did.

Scott, P. M. and G. A. Lawrence (1995). "Analysis of beer for fumonisins." Journal of Food Protection 58(12): 1379-1382. ://WOS:A1995TP33900017 Forty-one samples of beer were analyzed for fumonisins B-1 and B-2 (FB1 and FB2) using an immunoaffinity column cleanup followed by liquid chromatographic (LC) analysis. These samples included three later brand resamplings. All LC analyses were carried out using o-phthaldialdehyde/2-mercaptoethanol (OPA/MCE) and/or 4-fluoro-7-nitrobenzofurazan (NBD-F) derivatization procedures, Detection limits were 0.4 to 1 ng of FB1 or FB2 per ml of beer with OPA/MCE and 0.7 to 3 ng/ml with NBD-F. Recoveries of FB1 and FB2 spiked into 8 different beer samples at 2 to 10 ng/ml ranged from 61 to 114% and 47 to 97%, respectively. Four samples (one of which was a resampled brand) contained > 2 ng of FB1 per ml (up to 59 ng/ml).

Scott, P. M. and G. A. Lawrence (1996). "Determination of hydrolysed fumonisin B-1 in alkali-processed corn foods." Food Additives and Contaminants 13(7): 823-832. ://WOS:A1996VH92300008 Treatment fumonisin B-1 (FB1)-contaminated corn with calcium hydroxide solution is known to cause large losses of FB1 and formation of the aminopentol AP(1) by hydrolysis. Methodology was developed for determination of AP(1) in foods manufactured from calcium hydroxide-processed corn. The ground food (tortilla chips, nacho chips, taco shells, or air-dried corn tortillas) was extracted with methanol-water (8:2) or methanol-acetonitrile-water (25:25:50), which also extracted FB1 and fumonisin B-2 (FB2). Clean-up for fumonisin determination was carried out on a 1 ml strong anion exchange (SAX) solid phase extraction (SPE) column. The water wash from this column, containing AP(1), was cleaned up on a 1 ml C-18 SPE column. AP(1) and, separately, FB1 and FB2 were determined as their o-phthaldialdehyde-mercaptoethanol (OPA/MCE) and, in some cases, 4-fluoro-7-nitrobenzofurazan (NBD- F) derivatives by gradient reverse phase liquid chromatography with fluorescence detection. Recoveries of AP(1), FB1 and FB2 from spiked samples were generally satisfactory, but FB1 and FB2 recoveries were low with some samples. Better recovery of FB1 with the methanol-acetonitrile-water (25:25:50) extraction solvent compared with methanol-water (8:2) was observed for naturally- contaminated samples. Detection limits were about 10 ng AP(1) per g and 20 ng FB1 and FB2 per g with OPA/MCE derivatization, but there were interferences for FB2. Analysis of 31 samples of alkali-processed corn foods (including three known already to contain FB1) showed measurable levels of AP(1) in nine samples, all < 100 ng/g and lower than the corresponding FB1 concentrations.

Scott, P. M. and G. A. Lawrence (1997). "Determination of aflatoxins in beer." Journal of Aoac International 80(6): 1229-1234. ://WOS:A1997YL25900013 Aflatoxins B-1, B-2, G(1), and G(2) were determined at parts-per-trillion levels in beer by immunoaffinity column cleanup and reversed-phase liquid chromatography (LC) with fluorescence detection after trifluoroacetic acid derivatization. Silanized vials were necessary for the evaporation step in order to obtain good recoveries of aflatoxins from spiked beer samples. Recoveries averaged 90-104%, 94%, 84-87%, and 89% for aflatoxins B-1, B-2, G(1), and G(2), respectively, at levels of 9.7-133 ng B-1, 46 ng B-2, 35-140 ng G(1), and 41 ng G(2)/L. Detection limits were 19-20 ng/L for aflatoxins B-1 and G(1) and 15-16 ng/L for aflatoxins B-2 and G(2) (signal-to-noise ratio = 3:1) obtained by using an excitation wavelength of 360 nm; at 340 nm these detection limits were lowered to about 2 ng/L. Analysis of 24 beer samples, the majority from the United States and Mexico, showed natural contamination of one sample of Mexican beer at 49 ng B-1/L when determined at 360 nm excitation, but reanalysis of 23 of the samples using 340 nm excitation indicated that an additional 4 Mexican samples and one Brazilian sample contained aflatoxin B-1 at low levels (<10 ng/L).

Scott, P. M., J. W. Lawrence, et al. (1970). "Detection of Mycotoxins by Thin-Layer Chromatography - Application to Screening of Fungal Extracts." Applied Microbiology 20(5): 839-&. ://WOS:A1970H858300039

Scott, P. M. and M. W. Trucksess (1997). "Application of immunoaffinity columns to mycotoxin analysis." Journal of Aoac International 80(5): 941-949. ://WOS:A1997XY20800006 Immunoaffinity columns (IACs) are widely used for cleanup and isolation of mycotoxins extracted from foods and biological fluids, particularly aflatoxins, ochratoxin A, and fumonisins, The columns are prepared by binding antibodies specific for a given mycotoxin to a specially activated solid-phase support and packing the support suspended in aqueous buffer solution into a cartridge, The mycotoxin in the extract or fluid binds to the antibody, impurities are removed with water or aqueous solution, and then the mycotoxin is desorbed with a miscible solvent such as methanol, Further separation can be performed with IAC, followed by liquid chromatographic (LC) quantitation, either off-line or on-line in an automated system, or by fluorometry, IACs have been used by laboratories that developed the antibodies but are also available commercially for aflatoxins, ochratoxin A, fumonisins, zearalenone, and deoxynivalenol. Among commercial IACs, Aflatest P is used as the cleanup step in an LC method and in a solution fluorometry method for corn, peanuts, and peanut butter that was adopted as an AOAC INTERNATIONAL Official Method after evaluation by an international collaborative study, As part of a fluorometer-based test kit, aflatest P was further certified by the AOAC Research Institute to measure total aflatoxins in 10 grains and grain products. IACs can concentrate the analyte from a large amount of sample, allowing detection limits at low parts-per-trillion levels in some cases (e.g., for aflatoxin M-1 and ochratoxin A in liquid food matrixes), Regeneration of IACs for reuse in aflatoxin, ochratoxin A, fumonisin, and zearalenone analyses has been investigated.

Scott, P. M., Vanwalbe.W, et al. (1967). "Formation of Aflatoxins by Aspergillus Ostianus Wehmer." Applied Microbiology 15(4): 945-&. ://WOS:A19679670300049

Scott, P. M., Vanwalbe.W, et al. (1972). "Mycotoxins (Ochratoxin-a, Citrinin, and Sterigmatocystin) and Toxigenic Fungi in Grains and Other Agricultural Products." Journal of Agricultural and Food Chemistry 20(6): 1103-&. ://WOS:A1972O032700003 AND http://www.botanischergarten.ch/Bt/Scott-Mycotoxins-Grains-1972.pdf

Scott, P. M., D. Weber, et al. (1997). "Gas chromatography mass spectrometry of Alternaria mycotoxins." Journal of Chromatography A 765(2): 255-263. ://WOS:A1997WX83600015 Heptafluorobutyrate (HFB) derivatives have not previously been used for GC of Alternaria mycotoxins. Capillary (0.5 mu m film) GC- mass spectrometry (MS) showed that full and partial derivatives of alternariol (AGH), alternariol monomethyl ether (AME) and altenuene (ALT); a structurally uncharacterized derivative of altertoxin I (ALTX-I); and a tris-HFB derivative of tenuazonic acid (TA) were formed with heptafluorobutyric anhydride and a basic catalyst. Full and partial trimethylsilyl (TMS) ethers of these mycotoxins were formed with Tri-Sil TBT. Apple juice extracts caused increased response in GC-MS of AGH bis-HFB and bis-TMS derivatives. Natural occurrence of AGH in apple juice has been demonstrated.

Scott, P. M., J. M. Yeung, et al. (1997). "Evaluation of enzyme-linked immunosorbent assay for analysis of beer for fumonisins." Food Additives and Contaminants 14(5): 445-450. ://WOS:A1997XJ75500004 A recently developed sensitive indirect competitive enzyme-linked immunosorbent assay, (ELISA) was applied to the determination of fumonisins in beer. Intra-assay and inter-assay recoveries averaged 98.7-102.8% at added fumonisin B-1 (FB1) levels of 0.5-50 ng/ml beer, and coefficients of variation were 2.8-4.4 and 4.7-8.6%, respectively. Cross-reactivity of fumonisin B-2 (FB2) compared with FB1 averaged 67% in beer. Two experiments were carried out to compare ELISA with liquid chromatography (LC) for determination of fumonisins in beer. In the first experiment, 19 samples (five previously known positive, nine other samples and Jive spiked samples) were passed through commercial immunoaffinity columns (ICs) and analysed by LC before conducting blind ELISA determinations on the extracts and beers directly. The known positive beers and extracts were used as blind duplicates. The second comparative experiment screened 46 beer samples by ELISA and then 22 positive and three of the negative samples were analysed by LC; the highest level found was 64.3 ng total fumonisins/ml measured by LC (24.7 ng/ml by ELISA). Regression analyses showed good correlation between ELISA and LC in the first experiment but low level interferences (equivalent to up to 5.35 ng fumonisin/ml) were observed by ELISA in the IC extracts. Five of nine beers negative by LC showed < 1 ng/ml ELISA responses on direct beer analysis. The second comparative experiment indicated underestimation by ELISA. However, there were two samples which tested positive by ELISA (0.2 ng/ml) but were found negative by LC (results close to the detection limits of both methods, which were 0.1 or 0.2 ng/ml by ELISA and 0.1-0.15 ng each fumonisin/ml by LC). There were no false negatives. It is concluded that ELISA has considerable value in rapid screening of beer directly for fumonisins.

Scudamore, K. A., M. T. Hetmanski, et al. (1997). "Occurrence of mycotoxins in raw ingredients used for animal feeding stuffs in the United Kingdom in 1992." Food Additives and Contaminants 14(2): 157-173. ://A1997WK51100007 AND http://www.botanischergarten.ch/Bt/Scudamore-Occurrence-raw-ingredients-1997.pdf

Scudamore, K. A. and C. T. Livesey (1998). "Occurrence and significance of mycotoxins in forage crops and silage: a review." Journal of the Science of Food and Agriculture 77(1): 1-17. ://000073633600001

Scudamore, K. A., S. Nawaz, et al. (1998). "Mycotoxins in ingredients of animal feeding stuffs: II. determination of mycotoxins in maize and maize products." Food Additives and Contaminants 15(1): 30-55. ://000071522200004 AND http://www.botanischergarten.ch/BtScudamore-Mycotoxins-II-det-1998.pdf

Scudamore, K. A. and S. Patel (2000). "Survey for aflatoxins, ochratoxin A, zearalenone and fumonisins in maize imported into the United Kingdom." Food Additives and Contaminants 17(5): 407-416. ://000087835900006 This survey examined 140 samples of raw maize as received at ports or at major maize mills in the UK and 12 after initial cleaning. Samples were examined for aflatoxins B-1, B-2, G(1) and G(2), ochratoxin A, zearalenone and fumonisins B-1, B-2 and B-3 using fully validated analytical HPLC methods with detection limits of 0.1 mu g/kg for each aflatoxin and ochratoxin A, 4 mu g/kg for zearalenone and 10 mu g/kg for each fumonisin. 95.0% and 92.1% of samples met the new EC statutory maximum permissible level for total aflatoxins and aflatoxin BI respectively. The maximum concentration of ochratoxin A found was 1.5 mu g/kg. Zearalenone and fumonisins were detected in almost every sample with 41.7% of maize containing move than 100 mu g/kg of zearalenone and 48% of samples containing move than 1000 mu g/kg total fumonisins. Initial cleaning of raw maize reduced aflatoxin concentrations by about 40% and total fumonisins by 32%.

Seegers, J. C., A. M. Joubert, et al. (2000). "Fumonisin B-1 influenced the effects of arachidonic acid, prostaglandins E2 and A2 on cell cycle progression, apoptosis induction, tyrosine- and CDC2-kinase activity in oesophageal cancer cells." Prostaglandins Leukotrienes and Essential Fatty Acids 62(2): 75-84. ://000086607400002 In a previous study, we showed that, of a group of lipids including arachidonic acid (AA), prostaglandins E2 (PGE2) and A2 (PGA2), PGA2 had the most marked effect on the inhibition of cell growth, activation of tyrosine kinase activity, lowering of the number of G1-phase cells, and induction of p53 levels in oesophageal carcinoma (WHCO3) cells(17). No significant effects by the three lipids were seen in normal monkey kidney cells. In the present study, the effects of the inhibitor of ceramide synthesis, fumonisin B-1 (FB1), a metabolite of Fusarium verticillioides (= F.moniliforme) which is implicated in the high incidence of oesophageal cancer, were determined on AA, PGE2 and PGA2 WHCO3 treated cells. In the presence of FB1, the lipid-enhanced tyrosine kinase activity was lowered. Flow cytometric and morphological studies showed that FB1 lowered the marked apoptosis induced by especially PGA2. FB1, however, in combination with AA, PGE2 or PGA2 increased the number of G2/M cells. AA>PGE2>PGA2 alone decreased CDC2-kinase activity, but, in the presence of FB1, CDC2-kinase activity was significantly increased. The PGA2- and AA-induced p53 levels were lowered in the presence of FB1. We concluded that FB1 diminished the cytotoxic effects of the lipids on oesophageal tumour cells. (C) 2000 Harcourt Publishers Ltd.

Seo, J. A., R. H. Proctor, et al. (2001). "Characterization of four clustered and coregulated genes associated with fumonisin biosynthesis in Fusarium verticillioides." Fungal Genetics and Biology 34(3): 155-165. ://000173226700002 Fumonisins are mycotoxins that cause several fatal animal diseases, including cancer in rats and mice. These toxins are produced by several Fusarium species, including the maize pathogen Fusarium verticillioides, and can accumulate in maize infected with the fungus. We have identified four F. verticillioides genes (FUM6, FUM7, FUM8, and FUM9) adjacent to FUM5, a previously identified polyketide synthase gene that is required for fumonisin biosynthesis. Gene disruption analysis revealed that FUM6 and FUM8 are required for fumonisin production and Northern blot analysis revealed that expression of all four recently identified genes is correlated with fumonisin production. Nucleotide sequence analysis indicated that the predicted FUM6 translation product is most similar to cytochrome P450 monooxygenase-P450 reductase fusion proteins and the predicted products of FUM7, FUM8, and FUM9 are most similar to type III alcohol dehydrogenases, class-II alpha- amino-transferases, and dioxygenases, respectively. Together, these data are consistent with FUM5 through FUM9 being part of a fumonisin biosynthetic gene cluster in F. verticillioides.

Setamou, M., K. F. Cardwell, et al. (1997). "Aspergillus flavus infection and aflatoxin contamination of preharvest maize in Benin." Plant Disease 81(11): 1323-1327. ://A1997YD50300019 Eighty and sixty maize fields were sampled in 1994 and 1995, respectively, to monitor Aspergillus infection and aflatoxin contamination of preharvest maize in Benin. Three Aspergillus species were isolated from different agroecological zones, with A. flavus being the most prevalent. The countrywide mean percentage of kernel infection was about 20% in both years. Aflatoxin was extracted from maize in at least 30% of the fields sampled. Toxin concentrations exhibited a distinct zonal variation, with relatively high levels in the Guinea Savanna. There was a trend toward higher rate of aflatoxin accumulation per percentage A. flavus infection from the south to the north. Damage by the ear borer, Mussidia nigrivenella, increased aflatoxin accumulation in maize. Hence, the geographic pattern observed in the occurrence of A. flavus and aflatoxin may be related to the incidence of M. nigrivenella.

Setamou, M., K. F. Cardwell, et al. (1998). "Effect of insect damage to maize ears, with special reference to Mussidia nigrivenella (Lepidoptera : Pyralidae), on Aspergillus flavus (Deuteromycetes : Monoliales) infection and aflatoxin production in maize before harvest in the Republic of Benin." Journal of Economic Entomology 91(2): 433-438. ://000073485000015 and http://www.entsoc.org/pubs/jee/ and http://www.bioone.org/bioone/?request=get-journals-l... Maize infection by Aspergillus flavus Link and subsequent anatoxin contamination as affected by insect damage to maize ears before harvest was studied with surveys in farmers' fields and in a field trial in the Republic of Benin, West Africa. The most important pest species was the lepidopteran earborer Mussidia nigrivenella Ragonot. Percentage of grain infected by A. flavus and of samples contaminated with anatoxin, as well as the mean anatoxin content of samples, increased with increasing borer damage. Ears with <2% insect damage had an average of 11.7 and 43.6 ppb of anatoxin in 1994 and 1995, respectively. Ears in the highest damage class (i.e., > 10% damage) had an average anatoxin of 514.6 and 358.2 ppb in 1994 and 1995, respectively. In 1994 only, coleopteran species such as Sitophilus zeamais Motschulsky and Carpophilus sp. significantly increased levels of aflatoxin in grain samples. In a field trial using M. nigrivenella infestation and A. flavus inoculation treatments, the presence of the insect feeding resulted in increased kernel infection and anatoxin contamination. Artificial infestation with M. nigrivenella larvae increased anatoxin content of maize by an average of 45 ppb, whereas inoculation with A. flavus spores increased the toxin level by 517 ppb. The significant interaction between infestation and inoculation indicated that higher levels of anatoxin B1 were found when the fungus was associated with borers than with the fungus alone. M. nigrivenlla was the major field pest connected with A. flavus infection and subsequent anatoxin production in preharvest maize in Benin.

Setamou, M., F. Schulthess, et al. (2002). "Natural enemies of the maize cob borer, Mussidia nigrivenella (Lepidoptera : Pyralidae) in Benin, West Africa." Bulletin of Entomological Research 92(4): 343-349. ://000177120100010 Mussidia nigrivenella Ragonot is a pest of maize cobs in West Africa. It significantly reduces maize yields and grain quality, with quantitative losses of 2-25% at harvest, and up to 10-15% indirect losses due to an increase in storage pest infestation levels. Infestation by M. nigrivenella also significantly increased the susceptibility of maize to Aspergillus flavus infection and subsequent aflatoxin contamination. Surveys conducted in different agro-ecological zones of Benin on cultivated and wild host plants during 1994- 1997 revealed one egg parasitoid, three larval parasitoids and one pupal parasitoid attacking M. nigrivenella. Egg parasitism was scarce on all host plants sampled and in all four agro- ecological zones. Parasitism by larval and pupal parasitoids was usually less than 10%, and varied with host plant species. Both larval and pupal parasitoids were rare or absent in cultivated maize fields. The solitary chalcidid pupal parasitoid, Antrocephalus crassipes Masi, was the predominant species, contributing approximately 53% of the observed mortality. Logistic regression analysis indicated that this parasitoid was more prevalent on fruits of Gardenia spp. (Rubiaceae) than on the other host plant species including maize used by M. nigrivenella, and was most abundant between February and September. The differences in parasitoid diversity and parasitism between Benin and other regions suggest that there are opportunities for biological control through introduction of exotic parasitoids or using the 'new association' approach, which uses natural enemies of closely related host species that occupy similar ecological niches to the target pest.

Severns, D. E., M. J. Clements, et al. (2003). "Comparison of Aspergillus ear rot and aflatoxin contamination in grain of high-oil and normal-oil corn hybrids." Journal of Food Protection 66(4): 637-643. ://000182130900015 High-oil corn (Zea mays L.) grain is a valuable component of feed for monogastric livestock. One method of increasing the concentration of oil in corn grain is the TopCross method. With TopCross, ears of a cytoplasmic male-sterile, normal-oil hybrid are pollinated by a male-fertile, high-oil synthetic hybrid. The concentration of oil in the resulting grain is increased because of xenia effects. Kernels of high-oil corn typically have a larger germ and a smaller endosperm than kernels of comparable normal hybrids. The growth of Aspergillus fiavus Link:Fr within germ tissue has been reported to be more extensive than that on the whole corn kernel; therefore, the severity of Aspergillus ear rot could be more extensive and aflatoxin concentrations could be higher in high-oil grain produced by TopCross than in grain with a lower concentration of oil. The objective of this study was to compare Aspergillus ear rot severity levels and aflatoxin concentrations in the grains of hybrids crossed with high-oil or-normal-oil pollinators. Fifteen hybrids were evaluated in 1998 and 1999 in Urbana, Ill. Primary ears were inoculated with A. flavus and evaluated for susceptibility to Aspergillus ear rot and aflatoxin production in grain. Concentrations of aflatoxin and oil in corn kernels were significantly higher for high-oil hybrids than for normal-oil hybrids; however, ear rot severity was unaffected by the type of pollinator. These results suggest that grain from high-oil hybrids is at greater risk for aflatoxin contamination during some growing seasons.

Sewram, V., N. Mshicileli, et al. (2003). "Fumonisin mycotoxins in human hair." Biomarkers 8(2): 110-118. ://000183550200003 This study shows for the first time the accumulation of fumonisin mycotoxins in human hair of population clusters exposed to contaminated maize, and thus the feasibility of human hair analysis for the assessment of past fumonisin exposure. Composite hair samples were obtained from the Bizana, Butterworth and Centane districts within the Transkei region of the Eastern Cape Province of South Africa. Following methanol extraction and strong anion exchange clean up, the fumonisins FB1, FB2 and FB3 were detected using high performance liquid chromatography coupled to electrospray ionization-mass spectrometry (HPLC-ESI-MS). Hair from Centane and Butterworth showed mean levels of FB1 of 26.7 and 23.5 mug kg(-1) hair, respectively. FB2 was only detected in hair from Centane and in one sampling point in Butterworth, with mean levels of 6.5 and 5.7 mug kg(-1) hair, respectively. Hair samples from Bizana, on the other hand, were found to contain higher levels of FB1 (mean 33.0 mug kg(-1) hair) and FB2 (mean 11.1 mug kg(-1) hair). No samples contained more than trace levels of FB3. Recoveries from spiked hair samples using this method ranged from 81% to 101%, demonstrating the applicability of hair analysis in assessing human exposure to fumonisin mycotoxins.

Sewram, V., J. J. Nair, et al. (2001). "Assessing chronic exposure to fumonisin mycotoxins: The use of hair as a suitable noninvasive matrix." Journal of Analytical Toxicology 25(6): 450-455. ://000170621500005

Sewram, V., T. W. Nieuwoudt, et al. (1999). "Determination of the Fusarium mycotoxins, fusaproliferin and beauvericin by high-performance liquid chromatography- electrospray ionization mass spectrometry." Journal of Chromatography A 858(2): 175-185. ://000083154900004 A method is described using LC-MS for the detection of the mycotoxins fusaproliferin (FUS) and beauvericin (BEA) in cultures of Fusarium subglutinans and in naturally contaminated maize. Protonated molecular ion signals for FUS and BEA were observed at m/z 445 and m/z 784, respectively. Collision induced dissociation of the readily dehydrated protonated molecular ion of the sesterterpene FUS (m/z 427) led to the loss of another water molecule (m/z 409) and acetic acid (m/z 385), while the cyclic lactone trimer BEA fragmented to yield the protonated dimer (m/z 523) and monomer (m/z 262), respectively. Detection of FUS was best performed in the MS-MS mode while BEA displayed a stronger signal in the MS mode. The on-column instrumental detection limits for pure FUS and BEA were found to be 2 ng and 20 pg (S/N = 2) while those in naturally contaminated maize were 1 mu g/kg and 0.5 mu g/kg, respectively. Five South African strains of F. subglutinans were analyzed following methanol extraction of which four produced FUS at levels between 330 mg/kg and 2630 mg/kg while only three produced BEA at levels between 140 mg/kg and 700 mg/kg. Application of this method to naturally contaminated maize samples from the Transkei region of South Africa showed FUS at levels of 8.8-39.6 mu g/kg and BEA at 7.6-238.8 mu g/kg. (C) 1999 Elsevier Science B.V. All rights reserved.

Sewram, V., G. S. Shepard, et al. (2003). "Improving extraction of fumonisin mycotoxins from Brazilian corn-based infant foods." Journal of Food Protection 66(5): 854-859. ://000182669900020 The current AOAC International methods for the determination of fumonisins have been validated for corn and cornflakes but have produced low recoveries and high variability when applied to processed corn products for infants. Hence, an investigation was undertaken to improve the extraction efficiency for fumonisins by investigating the use of different extraction solvents. Corn-based infant foods containing cornmeal, corn starch, and corn flour were purchased in the city of Campinas, state of Sao Paulo, Brazil, and were analyzed for fumonisins B- 1 (FB1), B-2 (FB2), and B-3 (FB3) following extraction with a range of solvents. Comparison of the results from each of the samples indicated that acidified 70% aqueous methanol at pH 4.0 provided the best overall performance, whereas a methanol/boric acid (pH 9.2) mixture displayed poor extraction efficiency. Extraction with acidified 70% aqueous methanol showed seven of eight test samples to be positive for 1713 1 (range, 30 to 6,127 mug/kg; relative SD, 4.2 to 51.7%), two of eight samples to be positive for FB2 (range, 53 to 1,738 mug/kg; relative SD, 4.5 to 5.3%), and one of eight samples to be positive for FB3 (575 mug/kg). For samples in which extraction with phosphate- buffered mixtures (pH 3) proved superior, the method suffered from poor chromatography due to interfering compounds. The findings indicate that matrix interferences play a significant role in the extractability, cleanup, and chromatography of the fumonisins.

Shah, H. U., T. J. Simpson, et al. (2010). "Mould incidence and mycotoxin contamination in maize kernels from Swat Valley, North West Frontier Province of Pakistan." Food and Chemical Toxicology 48(4): 1111-1116. ://WOS:000276593100017 Mould incidence and aflatoxin B1 (AFB1) and ochratoxin A (OTA) contamination as well as proximate composition and minerals content of maize kernels from Swat Valley, North West Frontier Province of Pakistan was studied during the year, 2007. Results indicated that the mean moisture content of the kernels was within the recommended safe storage levels of <= 15%. Across the whole valley, Aspergillus. Fusar-Penicillium and Rhizopus were the most predominant fungal genera identified and amongst the mycotoxigenic species, Aspergillus flavus had the highest incidence. AFB1 content ranged from none to 30.921 mu g/kg with the average values of 14.94 and 16.22 mu g/kg for Upper and Lower Swat regions, respectively. Similar trend was observed for OTA with the contamination level ranged from <0.001 to 7.32 mu g/kg. A significant numbers of samples contained AFB1 and OTA levels above the safe limits as recommended by the USFDA and EU but on the average the results were within the safe limit. These results indicate that maize consumers in Swat Valley may be exposed to the danger of aflatoxins and ochratoxins poisoning. Thus, there is a need for policy makers to establish and enforce maize quality standards and regulations related to moulds and mycotoxins across the area. (C) 2010 Elsevier Ltd. All rights reserved.

Sharma, M. and C. Marquez (2001). "Determination of aflatoxins in domestic pet foods (dog and cat) using immunoaffinity column and HPLC." Animal Feed Science and Technology 93(1-2): 109-114. ://000171062100008 A determination of aflatoxins in 35 samples of domestic pet foods (dog and cat) was carried out. A reversed phase HPLC method with fluorometric detection is described for the determination and quantification of aflatoxins B-1, B-2, G1(,) G(2), M-1, M-2, P-1 and aflatoxicol after an immunoaffinity column clean up. The samples were drawn from 12 different commercially available pet foods in Mexico. The presence of seven aflatoxins and aflatoxicol was observed in most of the samples. Aflatoxin B-1 was the mycotoxin found with higher frequency (0.885) and was at high concentration in six samples (17.1%) of both dog and cat foods, Two of the samples contained a high concentration of total aflatoxins 72.4 and 59.7 ng/g. The total contamination of AFB(1) in cat food was higher in comparison to the dog food but statistical analysis using ANOVA one way and Dunnes test showed that there was no significant difference between cat and dog food samples, which was because of high standard deviation for the samples. Methods of analysis were tested by mean average recoveries of different aflatoxins and aflatoxicol spiked at levels of 0.5-8.0 ng/g ranged from 83-87% for AFG(1) and AFB(2) with relative standard deviation of <7% for AFP(1). Detection limits were 3-7 ng/g based on a signal- to-noise ratio of 4:1 at (ex) 370 nm/lambda (em) 418 nm. In conclusion, aflatoxin B-1 was present in most of the samples which even at low concentrations is of great concern for human and animal health. Maize was the main ingredient in all the contaminated samples. (C) 2001 Elsevier Science B.V. All rights reserved.

Shephard, G. S. (2003). "Aflatoxin and food safety: Recent African perspectives." Journal of Toxicology-Toxin Reviews 22(2-3): 267-286. ://000185165300007 The issue of food safety in Africa is one which interacts with and is frequently subjugate to issues of food security, especially in geographic areas where food shortages are caused by recurrent natural weather phenomena such as drought. In addition, many subsistence farming communities in Africa are reliant on the consumption of home-grown crops, irrespective of the quality considerations normally applied in the developed world. Nevertheless, some African governments have instituted food safety regulations to control mycotoxin, especially aflatoxin, contamination of the national food supply and research into natural occurrence of aflatoxins in a range of local foods is widely conducted. This review summarises the work published in this field through the previous decade. It emphasizes that much of the research effort has been performed in South Africa, Egypt and in various countries in west Africa including Ghana, Nigeria and The Gambia. Although much of the published research deals with levels-of aflatoxin contamination in staple foods such as maize and groundnuts, other particularly local foods such as cured and smoke-dried fish have been implicated as sources of dietary aflatoxin in various areas of Africa. The conclusion to be drawn from this survey is that aflatoxin exposure remains an important aspect of food safety which needs to be addressed by African communities.

Shephard, G. S. (2008). "Impact of mycotoxins on human health in developing countries." Food Additives and Contaminants 25: 146-151. ://WOS:000253659900003 NOT IN EZB, NOT IN NEBIS Adverse human health effects from the consumption of mycotoxins have occurred for many centuries. Although mycotoxin contamination of agricultural products still occurs in the developed world, the application of modern agricultural practices and the presence of a legislatively regulated food processing and marketing system have greatly reduced mycotoxin exposure in these populations. At the mycotoxin contamination levels generally found in food products traded in these market economies, adverse human health effects have largely been overcome. However, in the developing world, where climatic and crop storage conditions are frequently conducive to fungal growth and mycotoxin production, much of the population relies on subsistence farming or on unregulated local markets. The extent to which mycotoxins affect human health is difficult to investigate in countries whose health systems lack capacity and in which resources are limited. Aflatoxin B-1, the toxin on which major resources have been expended, has long been linked to liver cancer, yet its other effects, such as immune suppression and growth faltering previously observed in veterinary studies, are only now being investigated and characterized in human populations. The extent to which factors such as immune suppression contribute to the overall burden of infectious disease is difficult to quantify, but is undoubtedly significant. Thus, food safety remains an important opportunity for addressing current health problems in developing countries.

Shephard, G. S., N. L. Leggott, et al. (2002). "Preparation of South African maize porridge: effect on fumonisin mycotoxin levels." South African Journal of Science 98(7-8): 393-396. ://000179074700022 The estimated levels of fumonisin exposure in South African communities that consume maize as their staple diet have previously been based on the analysis of raw maize collected from subsistence farmers, rather than on analysis of traditionally cooked food. During the preparation of a typical South African stiff porridge, fumonisin levels in naturally contaminated maize meal were reduced during cooking. A mean reduction in fumonisin B, levels of 23% was observed, with a correlation coefficient between the levels in uncooked meal and cooked porridge of r = 0.90 (P < 0.01). A survey of available maize consumption data from around the world indicated that the highest levels of maize consumption are found in the general Mexican population and in the rural population of the Transkei region of South Africa.

Shephard, G. S., W. F. O. Marasas, et al. (2000). "Natural occurrence of fumonisins in corn from Iran." Journal of Agricultural and Food Chemistry 48(5): 1860-1864. ://000087116000069 Corn collected in the Mazandaran and Isfahan Provinces of Iran was analyzed for fumonisin B-1 (FB1), fumonisin B-2 (FB2), and fumonisin B-3 (FB3). The samples from Mazandaran Province, situated on the Caspian littoral of Iran, were random samples from farmers' corn lots collected in September 1998, whereas those from Isfahan Province, situated further south in the center of Iran, were bought as corn cobs in the local retail market during October 1998. All 11 samples from Mazandaran showed high levels of fumonisin contamination with FB1 levels between 1.270 and 3.980 mu g/g, FB2 levels between 0.190 and 1.175 mu g/g, and FB3 levels between 0.155 and 0.960 mu g/g. Samples from Isfahan showed lower levels of contamination with eight of eight samples having detectable FB1 (0.010-0.590 mu g/g), two of eight samples having detectable FB2 (0.050 -0.075 mu g/g), and two of eight samples having detectable FB3 (0.050- 0.075 mu g/g). This is the first report of fumonisin contamination of corn from Iran, in which samples from the area of high esophageal cancer on the Caspian littoral have been shown to contain high levels of fumonisins.

Shephard, G. S., W. F. O. Marasas, et al. (2002). "Fumonisin B-1 in maize harvested in Iran during 1999." Food Additives and Contaminants 19(7): 676-679. ://000176754000007 The fumonisin B-1 (FB1) contamination of maize collected in two areas of Iran during 1999 was determined. The 20 maize samples from Mazandaran Province, situated on the Caspian littoral of Iran, consisted of random samples of farmers' lots and were all contaminated with FB1 at a mean level of 3.18 mg kg(-1) (range 0.68-7.66 mg kg(-1)). The 10 samples (of the same maize cultivar) from Isfahan Province in central Iran were purchased as maize cobs in local retail markets and had mean FB1 levels of 0.22 mg kg(-1) (mean of all samples, 6/10 samples positive, range <0.01-0.88 mg kg(-1)). The FB1 levels in Mazandaran, an area of high oesophageal cancer, were significantly (p < 0.0001) higher than the FB1 levels found in maize from Isfahan, an area of low oesophageal cancer in Iran.

Shephard, G. S. and V. Sewram (2004). "Determination of the mycotoxin fumonisin B-1 in maize by reversed-phase thin-layer chromatography: a collaborative study." Food Additives and Contaminants 21(5): 498-505. ://000221241900011 A simple and cost-effective method using thin-layer chromatography for the determination of the mycotoxin fumonisin B-1 in maize is described. The analytical method consisted of the extraction of ground maize by shaking with methanol/water (75: 25) for 60 min and clean-up of the resultant extract by means of strong anion exchange solid-phase extraction. The purified residue, formed by evaporation of the elution solvent, was reacted with fluorescamine and the fumonisin B-1-derivative was separated by reversed- phase thin-layer chromatography using a developing solution of methanol/aqueous 4% potassium chloride (70: 30). The derivatized FB1 was readily visualized as a greenish-yellow spot under long wavelength ultraviolet light and quantified by visual comparison with a set of similarly derivatized standards in the range 20-300 ng FB1 spotted on plate. Based on visual comparison, levels down to 0.5 mg kg(-1) were successfully estimated. The method was collaboratively studied in 14 laboratories using four duplicate maize meal samples (including a blank) and a spiked sample for determination of recovery. No significant difference was observed between mean FB1 levels by high-performance liquid chromatography or thin-layer chromatography. Based on within- laboratory relative standard deviations of 27.1-41.7% and between-laboratory relative standard deviations of 35.0-63.3%, the method can be considered semiquantitative. The mean recovery achieved by participants at a spiking level of 2.00 mg kg(-1) was 74.5%.

Shephard, G. S., V. Sewram, et al. (1999). "Production of the mycotoxins fusaproliferin and beauvericin by South African isolates in the Fusarium section Liseola." Journal of Agricultural and Food Chemistry 47(12): 5111-5115. ://000084374200045 The production of fusaproliferin (FUS), a recently described mycotoxin, and beauvericin (BEA), a mycotoxin recently reported to co- occur with FUS in Fusarium-infected corn, by South African isolates in the Fusarium section Liseola, was investigated. Five isolates each off. verticillioides, F. proliferatum, F. subglutinans, and F. globosum were cultured on corn kernels. Four each of the five South African isolates off. proliferatum and F: subglutinans produced FUS (10-1725 and 330- 2630 mg/kg, respectively). BEA was produced by four of the F. proliferatum strains (310-1130 mg/kg) and three of the F: subglutinans strains (140-700 mg/kg). The isolates of F. verticillioides failed to produce significant levels of either of these secondary metabolites. F, globosum was a weak producer of both in that one isolate of five produced 25 mg/kg FUS and five out of five produced BEA at levels ranging between 10 and 110 mg/kg. To further characterize these strains, their production of fumonisins B-1, B-2, and B-3, as well as moniliformin, was investigated. Of the four species investigated, fumonisins were produced by all except F. subglutinans, which in turn was the only species whose isolates in this study produced moniliformin (four of five isolates, ranging from 155 to 2095 mg/kg). Analysis of visibly Fusarium- infected home-grown corn collected in the Transkei region of the Eastern Cape Province of South Africa showed that nine of the ten samples contained low levels of FUS (up to 62 mu g/kg), whereas all ten samples showed BEA contamination ranging from 8 to 1734 mu g/kg with a mean of 258 mu g/kg.

Shephard, G. S. and P. W. Snijman (1999). "Elimination and excretion of a single dose of the mycotoxin fumonisin B-2 in a nonhuman primate." Food and Chemical Toxicology 37(2-3): 111-116. ://000079844600003 The mycotoxin fumonisin B-2 (FB2), which can be present at significant levels in maize infected with the fungus Fusarium moniliforme, was dosed both iv and by gavage to vervel monkeys. It was rapidly eliminated from the plasma of vervet monkeys dosed iv with 2 mg FB2/kg body mass. The concentration of FB2 in plasma after the iv dose was characterized by an initial distributional phase and a subsequent elimination phase with a mean half-life of 18 min. When two monkeys were dosed by gavage with a single bolus (7.5 mg/kg body mass), only one showed detectable trace levels of FB2 in plasma (25-40 ng/ml over the 3-5 hr period after dosing). This indicates that, like FB1, FB2 has a limited bioavailability. Urinary excretion of FB2 was extremely low, even after iv dosing. In total, a mean of 4.1% of the iv dose and 0.2% of the gavage dose was recovered in urine over a 7-day period. The predominant route of excretion was via the faeces, mainly as the unmetabolized toxin or as a partially hydrolysed analogue, with the latter accounting for between 6% and 47% of the dose. Limited amounts (maximum of 1.1%) of the fully hydrolysed aminopolyol backbone of FB2 were recovered in faeces. (C) 1999 Elsevier Science Ltd. All rights reserved.

Shephard, G. S., E. W. Sydenham, et al. (1990). "Quantitative-Determination of Fumonisin-B1 and Fumonisins-B2 by High-Performance Liquid- Chromatography with Fluorescence Detection." Journal of Liquid Chromatography 13(10): 2077-2087. ://A1990EF59600015

Shephard, G. S., P. G. Thiel, et al. (1993). "Isolation and Determination of Aal Phytotoxins from Corn Cultures of the Fungus Alternaria-Alternata F Sp Lycopersici." Journal of Chromatography 641(1): 95-100. ://A1993LL52900012 The fungus Alternaria alternata f. sp. lycopersici produces a group of four related host-specific phytotoxins (AAL toxins) which can be divided into two groups (TA and TB), each of which exists as an equilibrium mixture of two structural isomers. The AAL toxins were isolated from com cultures by aqueous extraction, followed by purification on Amberlite XAD-2 resin, separation of TA from TB on silica gel and final purification on a semi-preparative high-performance liquid chromatographic (HPLC) system. A rapid, sensitive and reproducible method was developed to determine these toxins in culture material in order to monitor toxin production on com cultures. The method consisted of aqueous extraction, C18 solid-phase extraction clean-up, precolumn derivatization with o- phthaldialdehyde and reversed-phase HPLC with fluorescence detection. An isocratic HPLC system was developed that separated the structural isomers of TA and TB within a chromatographic analysis time of 24 min.

Shephard, G. S., P. G. Thiel, et al. (1996). "Worldwide survey of fumonisin contamination of corn and corn- based products." Journal of Aoac International 79(3): 671-687. ://A1996UN11000011 As part of a comprehensive risk assessment study for fumonisins, reliable data on exposure of populations to these dietary toxins must be obtained. To assess the extent of worldwide exposure, the published literature on the contamination of food and feed supplies has been reviewed and supplemented with unpublished material from various international sources, Fumonisin contamination of corn and corn-based products occurs in many countries. Animal mycotoxicoses such as equine leukoencephalomalacia and porcine pulmonary edema are caused by heavily contaminated animal feeds. For example, as much as 330 mu g/g fumonisin B-1 (FB1) has been found in swine feed, Although commercially available refined corn products for human consumption are generally contaminated at levels below 1 mu g/g FB1, individual products in certain countries can reach far higher levels. Health risks associated with consumption of these products depend on the extent to which they are consumed in a varied diet. Home-grown corn in certain rural areas, where it also constitutes the staple diet, can be contaminated at >100 mu g/g. Consumption of corn contaminated at these high levels has been associated with a high incidence of esophageal cancer in these areas.

Shephard, G. S., P. G. Thiel, et al. (1992). "Determination of Fumonisin-B1 in Plasma and Urine by High- Performance Liquid-Chromatography." Journal of Chromatography-Biomedical Applications 574(2): 299-304. ://A1992HG32200016 Fumonisin B1 (FB1), the major compound of the newly described fumonisin mycotoxins, has been shown to be the causative agent of the animal diseases leukoencephalomalacia in horses and pulmonary oedema in pigs. Whereas previous analytical methods have dealt with the determination of FB1 in feed and foodstuffs, this report for the first time details methods for FB1 determination in the physiological fluids, plasma and urine. The methods involve solid-phase anion-exchange clean-up, precolumn derivatisation with o- phthaldialdehyde and reversed- phase high-performance liquid chromatography with fluorescence detection. These methods were shown to be sensitive (detection limit around 50 ng ml-1), reproducible (relative standard deviation on six replicates less than 5%) and accurate (recoveries on spiked blank samples above 85%).

Shephard, G. S., P. G. Thiel, et al. (1992). "Initial Studies on the Toxicokinetics of Fumonisin-B1 in Rats." Food and Chemical Toxicology 30(4): 277-279. ://A1992JB92200003 Fumonisin B1 (FB1), the major compound in the fumonisin group of secondary metabolites of Fusarium moniliforme Sheldon, is associated with some human and animal diseases. After intraperitoneal dosing to rats (7.5 mg/kg), FB1 was rapidly absorbed and reached a maximum concentration in plasma within 20 min after injection. Thereafter, it underwent rapid removal from plasma, displaying a mono-exponential elimination phase that fitted a one-compartment model with a half-life of 18 min. Collection of 24- and 48-hr urine samples indicated that only 16% of the applied dose was eliminated unmetabolized in urine, all within the first 24-hr period following dosing. In contrast to this, a similar dose of FB1 given by gavage resulted in the recovery of only 0.4% of the FB1 in urine.

Shephard, G. S., P. G. Thiel, et al. (1995). "Liquid-Chromatographic Determination of the Mycotoxin Fumonisin B-2 in Physiological Samples." Journal of Chromatography A 692(1-2): 39-43. ://A1995QJ00100005 The fungus Fusarium moniliforme produces a group of mycotoxins, the fumonisins, of which the most abundant are fumonisins B-1 (FB1) and B-2 (FB2). Previously developed analytical methods for the determination of FB1 in physiological samples have been modified for the determination of FB2 by the use of less polar extraction solvents. Plasma and urine extracts were purified on strong anion-exchange solid-phase extraction cartridges and fecal extracts on reversed-phase (C-18) cartridges. FB2 in purified extracts was determined by reversed-phase HPLC with fluorescence detection using preformed o-phthaldialdehyde derivatives. These methods were reproducible (R.S.D. of less than 6%) with recoveries greater than 85%. In a short preliminary study, they have been applied to the determination of the fate of FB2 dosed to rats by gavage. Of the dose given to the animals, over 90% was recovered unmetabolised in the feces within 48 h.

Shephard, G. S., P. G. Thiel, et al. (1994). "Biliary-Excretion of the Mycotoxin Fumonisin B-1 in Rats." Food and Chemical Toxicology 32(5): 489- 491. ://A1994NR57000011 The biliary excretion of the mycotoxin fumonisin B, (FB,), produced by the fungus Alsarium moniliforme Sheldon, has been measured in male Wistar rats. After ip injection of a solution of FB1 (7.5 mg/kg body weight), 67% of the applied dose was recovered in bile over a 24-hr period, 88% of this recovery being excreted in the first 4 hr after dosing. In contrast to these results, a similar dose of FB1 given by gavage resulted in only 0.2% recovery of the toxin in bile over a 24-hr period. Hence, although these results show that biliary excretion is a major route of elimination of FB1 from the circulation, only small amounts of the toxin appeared to be absorbed from the gut in rats.

Shephard, G. S., P. G. Thiel, et al. (1994). "Distribution and Excretion of a Single-Dose of the Mycotoxin Fumonisin B-1 in a Nonhuman Primate." Toxicon 32(6): 735-741. ://A1994NT95300009 Fumonisin B-1 (FB1), a toxic and carcinogenic secondary metabolite of the fungus Fusarium moniliforme Sheldon, was administered either by i.v. injection or by gavage to vervet monkeys (Cercopithecus aethiops). FB1 dosed by i.v. injection to two female vervet monkeys was rapidly eliminated from plasma with a mean half-life during the elimination phase of 40 min. Analysis of urine and faeces over a 5 day period after dosing gave an average 47% recovery of the dose as FB1 and its hydrolysed analogues. Two female vervet monkeys were given a single gavage dose of C-14-labelled FB1. During the subsequent 3 day period, faecal excretion of radioactivity accounted for an average of 61% of the administered dose and urinary excretion 1.2%. Residual radioactivity was recovered in low levels from skeletal muscle (1%), liver (0.4%), brain (0.2%), kidney, heart, plasma, red blood cells and bile (each 0.1%), while the contents of the intestines accounted for a further 12% of the radioactive dose. In total, 76% of the administered radioactivity was recovered. Analysis of the faeces, intestinal contents and urine indicated that over 90% of the radioactivity in these samples was due to FB1 and its hydrolysis products.

Shephard, G. S., P. G. Thiel, et al. (1992). "Fate of a Single Dose of the C-14-Labeled Mycotoxin, Fumonisin- B1, in Rats." Toxicon 30(7): 768-770. ://A1992JD02000011 The fate of the mycotoxin fumonisin B1 (FB1) dosed to rats by i.p. injection and by gavage was traced using C-14-labelled FB1. Twenty-four hours after i.p. injection, 66% of the radioactivity was recovered in faeces, 32% in urine, 1% in liver and trace amounts (< 1%) in kidney and red blood cells. When dosed by gavage, all (101%) radioactivity was recovered in faeces and trace amounts were found in urine, liver, kidney and red blood cells. The bulk of the radioactivity recovered was unmetabolized FB1.

Shephard, G. S., P. G. Thiel, et al. (1995). "Toxicokinetics of the Mycotoxin Fumonisin B-2 in Rats." Food and Chemical Toxicology 33(7): 591- 595. ://A1995RL88400007 Fumonisin B-2 (FB2), a secondary metabolite of the fungus Fusarium moniliforme, was administered at a dose of 7.5 mg/kg body weight to male ED IX rats by ip injection or by gavage. FB2 was rapidly absorbed from the peritoneum, its level in plasma reaching a maximum within 20 min after injection. It was rapidly eliminated from plasma with a half-life of 26 min. After 24 hr, FB2 could not be detected in plasma (<20 ng/ml). Analysis of rat plasma for FB2 following a gavage dose failed to detect any toxin over a 6-hr period after dosing. The elimination of FB2 in the urine and faeces was determined over a 3-day period after dosing. After ip injection, the mean urinary excretion over this period was 1.2% and faecal elimination accounted for 84.1% of the dose. Similarly, after dosing by gavage, 0.2 and 82.0% of the dose was recovered in urine and faeces, respectively. FB2 appeared to be excreted unmetabolized.

Shephard, G. S., P. G. Thiel, et al. (1994). "Determination of the Mycotoxin Fumonisin B-1 and Identification of Its Partially Hydrolyzed Metabolites in the Feces of Nonhuman-Primates." Food and Chemical Toxicology 32(1): 23-29. ://A1994NA16300004 A method has been developed for the determination of fumonisin B-1 (FB1) in the faeces of non-human primates (vervet monkeys). The animals were dosed with C-14-labelled FB1, and the radioactive compounds in faeces were recovered by repeated extractions with 0.1M ethylenediaminetetraacetic acid. The extracts were cleaned-up on a reversed-phase (C-18) solid-phase extraction cartridge, and FB1 was determined by o- phthaldialdehyde derivatization and reversed-phase HPLC. The analytical method for the determination of FB1 in the faecal extracts was reproducible [2.6% relative standard deviation (RSD)] and accurate (recovery from spiked blank extracts of 93 +/- 2.9% RSD). Confirmation of the identification of FB1 in faeces was achieved using HPLC and thin-layer chromatography, which showed that the radioactivity extracted corresponded mainly to FB1 and a new metabolite with chromatographic properties similar to those of the mycotoxin. The new metabolite was identified by mass spectrometry and nuclear magnetic resonance spectroscopy to be an equilibrium mixture of the two structural isomers of partially hydrolysed FB,, which are formed by hydrolysis of one of the ester groups of the mycotoxin.

Shephard, G. S., L. vanderWesthuizen, et al. (1996). "Disruption of sphingolipid metabolism in non-human primates consuming diets of fumonisin-containing Fusarium moniliforme culture material." Toxicon 34(5): 527-534. ://A1996UN92600004 G. S. Shephard, L. van der Westhuizen, P. G. Thiel, W. C. A. Gelderblom, W. F. O. Marasas and D. J. van Schalkwyk. Disruption of sphingolipid metabolism in non-human primates consuming diets of fumonisin-containing Fusarium moniliforme culture material. Toxicon 34, 527-534, 1996.-The fumonisin mycotoxins are produced by Fusarium moniliforme Sheldon, a contaminant of corn worldwide. The two most abundant analogues (fumonisins B-1 and B-2) are known to be potent inhibitors of sphingosine N- acyltransferase (ceramide synthase) and hence to disrupt de novo sphingolipid biosynthesis. The sphingoid bases, sphingosine and sphinganine (and hence their ratio), were measured at varying intervals over a period of 60 weeks in the serum of non-human primates (vervet monkeys; Cercopithecus aethiops) which were consuming diets containing 'low' and 'high' amounts of F. moniliforme culture material, such that their total daily fumonisin intake was approximately 0.3 and 0.8 mg/kg body weight/day, respectively. Although no significant differences were found in the serum levels of sphingosine compared to controls, serum sphinganine levels in the experimental groups (mean of 219 nM and 325 nM, respectively) were significantly (P = 0.02) elevated above the levels in controls (mean 46 nM). As a consequence, the ratio sphinganine:sphingosine was significantly (P = 0.003) elevated from a mean of 0.43 in the control group to 1.72 and 2.57 in the experimental groups, respectively. Similar changes in sphingolipid profiles were also measured in urine with an increase of the ratio from 0.87 in controls to 1.58 and 2.17 in the experimental groups, although the differences were not statistically significant. Hence, the disruption of sphingolipid biosynthesis in vervet monkeys by fumonisins in culture material added to their diet can effectively be monitored in the serum as an elevation of the sphinganine:sphingosine ratio. Copyright (C) 1996 Elsevier Science Ltd.

Shier, W. T. (2000). "The fumonisin paradox: A review of research on oral bioavailability of fumonisin B-1, a mycotoxin produced by Fusarium moniliforme." Journal of Toxicology-Toxin Reviews 19(2): 161-187. ://000087187200003 The fumonisins are a series of mycotoxins produced by Fusarium moniliforme, a ubiquitous contaminant of stored corn (maize) worldwide. Consumption of food products contaminated with F. moniliforme has been correlated with increased risk of human esophageal cancer in epidemiological studies in southern Africa and China. The most abundant component, fumonisin B-1 (FB1), was isolated from F. moniliforme culture extracts using a shortterm tumor promoter bioassay to guide the fractionation. Purified FB1 has been confirmed to act as a tumor promoter in animal model systems; to cause hepatocellular carcinoma, cirrhosis and proximal tubule nephrosis in rats; and to mediate agriculturally significant diseases associated with consumption of F. moniliforme- contaminated feeds, including equine leukoencephalomalacia and porcine pulmonary edema. However, studies on the toxicokinetics of radiolabeled and unlabeled FB1 carried out by three research groups in five animal species all indicate that it is absorbed very poorly if at all when administered orally. There is no evidence for functionally significant metabolism of FB1 in vivo. These observations result in what might be called the "fumonisin paradox''-how can the toxin cause agriculturally significant diseases and possibly human cancer if it is not effectively adsorbed after oral administration? There are several plausible explanations including (i) an unknown, readily bioavailable contaminating toxin is responsible; (ii) higher FB1 bioavailability at lower dose; (iii) greater conversion to active metabolites at lower dose; (iv) bioaccumulation and (v) effective uptake of FB1 derivatives that are readily converted back to FB1 or active metabolites in the body. The full extent of the threat to food safety posed by the fumonisins will not be known until the factors affecting oral bioavailability are understood.

Shier, W. T., H. K. Abbas, et al. (2003). "Fumonisins: Abiogenic conversions of an environmental tumor promoter and common food contaminant." Journal of Toxicology-Toxin Reviews 22(4): 591-616. ://000187562600010 Fumonisins are a series of sphingosine-analog mycotoxins produced by Fusarium verticilhoides, a ubiquitous contaminant of stored corn (maize) world-wide. Extensive alterations in the structures of fumonisins are possible without complete loss of in vitro toxicity. Numerous laboratories have reported that fumonisin B-1 (FB1) levels in corn-derived foods are reduced during roasting and frying. We have conducted radiotracer studies to determine the fate of tritium-labeled FB1 added in laboratory models of corn flake manufacture (roasting), and tortilla chip manufacture (frying). These studies have confirmed that most, but not all, FB1 is converted to other substances during cooking. Under roasting conditions the major conversion pathway resulted in radiolabeled FB1 becoming covalently bound to proteins. Several lines of evidence supported a proposed role for FB1-anhydride, an intermediate formed by loss of water from a FB1 side chain, which enabled the toxin to bind covalently to proteins by reacting with amino groups. Under nixtamalization/frying conditions in preheated cooking oil, both FB1 and hydrolyzed FB1 were efficiently N- fatty acylated to the corresponding ceramide derivatives, presumably by fatty acid anhydrides or other degradation products formed from the fat by non- oxidative thermal degradation. The N-fatty acylated fumonisin derivatives were efficiently extracted from the chips into the hot oil. We will not understand the full threat to food safety posed by the fumonisins until we know what they are converted to during cooking, and what is the toxicity of those conversion products.

Shim, W. B., J. E. Flaherty, et al. (2003). "Comparison of fumonisin B-1 biosynthesis in maize germ and degermed kernels by Fusarium verticillioides." Journal of Food Protection 66(11): 2116-2122. ://000186488900022 Fusarium verticillioides produces a group of mycotoxins known as fumonisins in maize kernels. Fumonisins are associated with a variety of mycotoxicoses in humans and animals; thus, their presence in food is a considerable safety issue. This study addressed fumonisin B, (FB1) production in two components of the maize kernel, namely the germ tissues and the degermed kernel. Growth of F. verticillioides was similar in colonized germ tissue and degermed kernels, but FB1 production was at least five times higher in degermed maize kernels than in germ tissue. Expression of the fumonisin polyketide synthase gene, FUM1, as measured by beta- glucuronidase (GUS) and Northern blot analysis, followed the same pattern as FB1 production. Also correlated to FB1 was a concomitant drop in pH of the colonized degermed kernels. A time course experiment showed that degermed kernels inoculated with F. verticillioides became acidified over time (from pH 6.4 to 4.7 after 10 days of incubation), whereas colonized germ tissue became alkaline over the same period (from pH 6.5 to 8.5). Because conditions of acidic pH are conducive to FB1 production and alkaline pH is repressive, the observed correlation between the acidification of degermed kernels and the increase in FB1 provides one explanation for the observed differences in FB1 levels.

Shiu, C. M., J. J. Wang, et al. (2010). "Sensitive enzyme-linked immunosorbent assay and rapid one-step immunochromatographic strip for fumonisin B1 in grain-based food and feed samples." Journal of the Science of Food and Agriculture 90(6): 1020-1026. ://WOS:000276650500013 BACKGROUND: Maize contaminated with mycotoxin fumonisin B1 poses a global threat to agricultural production. In this study, polyclonal antibodies (pAb) specific to fumonisin B1 were generated from rabbits immunised with fumonisin B1-keyhole limpet haemocyanin (KLH). These antibodies were used to establish a sensitive competitive direct enzyme-linked immunosorbent assay (cdELISA) and gold nanoparticle immunochromatographic strip for detecting fumonisin B1 levels in maize-based foods and feeds. RESULTS: In cdELISA, fumonisins B1, B2 and B3 at concentrations of 0.42, 0.58 and 81.5 ng mL(-1) respectively caused 50% inhibition (IC50) of binding of fumonisin B1-horseradish peroxidase (HRP) to the antibodies. Effective on-site detection of fumonisin B1 was achieved by developing a rapid and sensitive pAb-based gold nanoparticle immunochromatographic strip. This strip had a detection limit of 5 ng mL-1 for fumonisin B1 in maize-based samples. Additionally, the whole analytical process could be completed within 10 min. Close examination of 15 maize-based samples by cdELISA revealed that 11 were fumonisin-positive, with a mean concentration of 435 +/- 20.1 ng g(-1). These results correlated well with those obtained by immunochromatographic strip. CONCLUSION: Both cdELISA and immunochromatographic strip methods established in this study are sensitive for rapid detection of fumonisins in agricultural commodities. (C) 2010 Society of Chemical Industry

Siame, B. A., S. F. Mpuchane, et al. (1998). "Occurrence of aflatoxins, fumonisin B1, and zearalenone in foods and feeds in Botswana." Journal of Food Protection 61(12): 1670-1673. ://000077525500013 AND http://cherubino.catchword.com/vl=12691755/cl=53/nw=... Sorghum and maize form the main dietary staple foods in Botswana. Other products such as peanuts, peanut butter, phane (an edible larval stage of an emperor moth Imbrasia belina Westwood) and pulses (cowpeas and beans) are also widely used as food and for the manufacture of feeds. These important food and feed commodities were analyzed for the presence of aflatoxins, fumonisin B1, and zearalenone. Aflatoxins were detected in 40% of the samples analyzed. The concentration of total aflatoxins ranged from 0.1 to 64 mu g/kg. The mean concentration ranged from 0.3 mu g/kg in sorghum to 23 mu g/kg in peanut butter. Peanut butter samples were the most contaminated (71%). No aflatoxins were detected in maize. Fumonisin B1 was detected in 36% of the samples. Maize samples were the most contaminated (85% of the samples) with the concentration ranging from 20 to 1,270 mu g/kg. No fumonisin B1 was detected in peanuts, phane, and beans. Zearalenone was only found in 2.6% of the samples analyzed at 40 mu g/kg. Aflatoxins were the most common toxins detected in foods and feeds in Botswana. However, fumonisin B1 was more prevalent in maize than aflatoxins or zearalenone.

Siegel, D., K. Andrae, et al. (2010). "Dynamic covalent hydrazine chemistry as a selective extraction and cleanup technique for the quantification of the Fusarium mycotoxin zearalenone in edible oils." Journal of Chromatography A 1217(15): 2206-2215. ://BIOSIS:PREV201000259635 A novel, cost-efficient method for the analytical extraction of the Fusarium mycotoxin zearalenone (ZON) from edible oils by dynamic covalent hydrazine chemistry (DCHC) was developed and validated for its application with high performance liquid chromatography-fluorescence detection (HPLC-FLD). ZON is extracted from the edible oil by hydrazone formation on a polymer resin functionalised with hydrazine groups and subsequently released by hydrolysis. Specifity and precision of this approach are superior to liquid partitioning or gel permeation chromatography (GPC). DCHC also extracts zearalanone (ZAN) but not alpha-beta-zearalenol or -zearalanol. The hydrodynamic properties of ZON, which were estimated using molecular simulation data, indicate that the compound is unaffected by nanofiltration through the resin pores and thus selectively extracted. The method's levels of detection and quantification are 10 and 30 mu g/kg, using 0.2 g of sample. Linearity is given in the range of 10-20,000 mu g/kg, the average recovery being 89%. Bias and relative standard deviations do not exceed 7%. in a sample survey of 44 commercial edible oils based on various agricultural commodities (maize, olives, nuts, seeds, etc.) ZON was detected in four maize oil samples, the average content in the positive samples being 99 mu g/kg. The HPLC-FLD results were confirmed by HPLC-tandem mass spectrometry and compared to those obtained by a liquid partitioning based sample preparation procedure. (C) 2010 Elsevier B.V. All rights reserved.

Silva, J. C., R. E. Minto, et al. (1996). "Isolation and characterization of the versicolorin B synthase gene from Aspergillus parasiticus - Expansion of the aflatoxin B-1 biosynthetic gene cluster." Journal of Biological Chemistry 271(23): 13600-13608. ://A1996UP38500046 and http://www.botanischergarten.ch/Mycotoxins/Silva-Isol-Versicolorin-1996.pdf Versicolorin B synthase catalyzes the side chain cyclizatian of racemic versiconal hemiacetal (7) to the bisfuran ring: system of (-)- versicolorin B (8), an essential transformation in the aflatoxin biosynthetic pathway of Aspergillus parasiticus. The dihydrobisfuran an is key to the mutagenic nature of aflatoxin B-1 (1), The protein, which skews 58% similarity and 38% identity with glucose oxidase from Aspergillus niger, possesses an amino-terminal sequence homologous to the ADP-binding region of other flavoenzymes. However, this enzyme does not require flavin or nicotinamide cofactors for its cyclase activity, The 643-amino acid native enzyme contains three potential sites for W-linked glycosylation, Asn-Xaa-Thr or Asn-Xaa-Ser. The cDNA and genomic clones of versicolorin B synthase were isolated by screening the respective libraries with random-primed DNA probes generated from an exact copy of an internal vbs sequence. This probe was created through polymerase chain reaction by using nondegenerate polymerase chain reaction primers derived from the amino acid sequences of peptide fragments of the enzyme. The 1985-base genomic rbs DNA sequence is interrupted by one intron of 53 nucleotides. Southern blotting, nucleotide sequencing, and detailed restriction mapping of the vbs-containing genomic clones revealed the presence of omtA, a methyltransferase active in the biosynthesis, 3.3 kilobases upstream of vbs and oriented in the opposite direction from vbs. The presence of omtA in close proximity to obs supports the theory that the genes encoding the aflatoxin biosynthetic enzymes in A, parasiticus are clustered.

Silva, J. C. and C. A. Townsend (1997). "Heterologous expression, isolation, and characterization of versicolorin B synthase from Aspergillus parasiticus - A key enzyme in the aflatoxin B-1 biosynthetic pathway." Journal of Biological Chemistry 272(2): 804-813. ://A1997WC04800018 Aflatoxin B-1 is a potent environmental carcinogen produced by certain strains of Aspergillus. Central to the biosynthesis of this mycotoxin is the reaction catalyzed by versicolorin B synthase (VBS) in which a racemic substrate, versiconal hemiacetal, is cyclized to an optically active product whose absolute configuration is crucial to the interaction of aflatoxin B-1 with DNA. Attempted over- production of VBS in Escherichia coli led principally to protein aggregated into inclusion bodies but also small amounts of soluble but catalytically inactive enzyme. Comparisons to wild-type VBS by SDS-polyacrylamide gel electrophoresis and after N glycosidase F treatment revealed that extensive glycosylation accounted for the mass discrepancy (7,000 +/- 1,500 Da) between the native and bacterially expressed proteins, Several over-expression systems in Saccharomyces cerevisiae were surveyed in which one that incorporated a secretion signal was found most successful. VBS of indistinguishable mass on SDS-polyacrylamide gel electrophoresis and kinetic properties from the wild-type enzyme could be obtained in 50-100-fold greater amounts and whose catalytic behavior has been examined. The translated protein sequence of VBS showed three potential N-glycosylation sites (Asn-Xaa-Ser/Thr) consistent with the modifications observed above and unexpectedly revealed extensive homology to the ADP-binding region prominently conserved in the glucose- methanol-choline (GMC) family of flavoenzymes. Over production of VBS in yeast marks the first aflatoxin biosynthetic enzyme to be so obtained and opens the way to direct study of the enzymology of this complex biosynthetic pathway.

Singsit, C., M. J. Adang, et al. (1997). "Expression of a Bacillus thuringiensis cryIA(c) gene in transgenic peanut plants and its efficacy against lesser cornstalk borer." Transgenic Research 6(2): 169-176. ://A1997WQ05400007 The invasion of peanut (Arachis hypogaea L.) pods and seeds by aflatoxin-forming species of Aspergillus is linked to injury by the lesser cornstalk borer and frequently causes a severe reduction in crop quality. The lesser cornstalk borer is susceptible to the lepidopteran-active Bacillus thuringiensis insecticidal crystal protein. We have introduced a codon-modified Bacillus thuringiensis crIA(c) gene into peanut using microprojectile bombardment. The toxin-coding region of a Bt cryIA(c) gene was reconstructed for expression in plants and the resulting 3.4 kb gene cassette (promoter: 1.8 kb coding: 3') was directly cloned into the BglII site of plant transformation vectors. The vectors contained the hph gene, conferring resistance to the antibiotic hygromycin. Somatic embryos initiated from immature peanut cotyledons of two cultivars were used as the target for bombardment. DNA from hygromycin-resistant embryogenic cell lines, regenerated plants, and a progeny plant showed the presence and integration of hph and Bt genes by PCR and/or Southern blot analyses. ELISA immunoassay of the CryIA(c) protein from the hygromycin-selected plants showed the expression of CryIA(c) protein up to 0.18% of total soluble protein, Insect feeding bioassay of transformed plants indicated various levels of resistance to the lesser cornstalk borer, from complete larval mortality to a 66% reduction in larval weight. A negative correlation between percent survival or larval weight and the amount of Bt CryIA(c) protein was recorded indicating in general that the higher the protein level the lower the survival or larval weight of the insect. Based on leaf bioassay, transformation of peanut with vectors containing the Bt cryIA(c) gene may be effective in protecting the peanut plants from damage by lepidopteran insect larvae of lesser cornstalk borer.

Sitas, F., D. M. Parkin, et al. (2008). "Part II: Cancer in indigenous Africans - causes and control." Lancet Oncology 9(8): 786-795. ://WOS:000258248800015 Africa has contributed substantial knowledge to the understanding of certain risk factors for cancer, such as the role of several infectious agents (eg, viruses, bacteria, and parasites), aflatoxins, and certain lifestyle factors. Although the relative importance of many lifestyle factors is becoming better understood in developed countries, more work is needed to understand the importance of these factors in different African settings. In view of the substantial genetic diversity in Africa, it would be prudent not to generailise too widely from one place to the next. We argue that risks for several exposures related to certain cancers differ from the patterns seen in developed countries. In this paper, we review the current knowledge of causes of some of the leading cancers in Africa, namely cancers of the cervix, breast, liver, prostate, stomach, bladder, and oesophagus, Kaposfs sarcoma, nonHodgkin lymphoma, and tobacco-related cancers. There are no comprehensive cancer-control programmes in Africa and provision of radiotherapy, chemotherapy, and palliation is inadequate. Certain cost-effective interventions, such as tobacco control, provision of antiretroviral therapy, and malarial and bilharzial control, can cause substantial decreases in the burden of some of these cancers. Vaccinations against hepatitis B and oncogenic human papilloma viruses can make the biggest difference, but very few countries in Africa can afford these vaccines without substantial subsidisation.

Smart, M. G., O. L. Shotwell, et al. (1990). "Pathogenesis in Aspergillus Ear Rot of Maize - Aflatoxin B-1 Levels in Grains around Wound- Inoculation Sites." Phytopathology 80(12): 1283-1286. ://A1990EP58600005

Sobek, E. A. and G. P. Munkvold (1999). "European corn borer (Lepidoptera : Pyralidae) larvae as vectors of Fusarium moniliforme, causing kernel rot and symptomless infection of maize kernels." Journal of Economic Entomology 92(3): 503-509. ://000081134100001 Field and greenhouse experiments were conducted to assess the ability of Ostrinia nubilalis (Hubner) larvae to act as vectors of Fusarium moniliforme J. Sheld. from maize leaf surfaces to kernels. Leaf surfaces of plants in the dough stage were sprayed with a spore suspension of F. moniliforme strain EA-2, after which plants were manually infested with O. nubilalis larvae or kernels were mechanically wounded. In 2 greenhouse experiments, O. nubilalis larvae significantly increased incidence of kernel rot symptoms and symptomless infection. Strain EA-2 was detected on O. nubilalis larvae, in plant debris in the leaf axils, and in 28-39% of F. moniliforme- infected kernels from plants manually infested with O. nubilalis. In the field, O. nubilalis infestation significantly increased incidence of kernel rot symptoms (1995) and symptomless infection (1994 and 1995). Symptomless infection was highest for treatments in which lan;ae were artificially contaminated with F. moniliforme strain EA-4 prior to manual infestation of plants. F. moniliforme strain EA-2 (from leaf surfaces) and strain EA-4 (from larvae) were recovered from kernels in the O. nubilalis-infested treatments in 1995. Results indicated that O. nubilalis larvae can act as vectors of F. moniliforme, increasing symptoms of Fusarium kernel rot and symptomless infection of kernels by F. moniliforme. Kernel wounding also is an important factor contributing to this disease.

Somashekar, D., E. R. Rati, et al. (2004). "PCR-restriction fragment length analysis of aflR gene for differentiation and detection of Aspergillus flavus and Aspergillus parasiticus in maize." International Journal of Food Microbiology 93(1): 101-107. ://000221775000009 Contamination of food and feedstuffs by Aspergillus species and their toxic metabolites is a serious problem as they have adverse effects on human and animal health. Hence, food contamination monitoring is an important activity, which gives information on the level and type of contamination. A PCR-based method of detection of Aspergillus species was developed in spiked samples of sterile maize flour. Gene-specific primers were designed to target aflR gene, and restriction fragment length polymorphism (RFLP) of the PCR product was done to differentiate Aspergillus flavus and Aspergillus parasiticus. Sterile maize flour was inoculated separately with A. flavus and A. parasiticus, each at several spore concentrations. Positive results ere obtained only after 12-h incubation in enriched media, with extracts of maize inoculated with A. flavus (10(1) spores/g) and A. parasiticus (104 spores/g). PCR products were subjected to restriction endonuclease (HincII and PvuII) analysis to look for RFLPs. PCR-RFLP patterns obtained with these two enzymes showed enough differences to distinguish A. flavus and A. parasiticus. This approach of differentiating these two species would be simpler, less costly and quicker than conventional sequencing of PCR products. (C) 2003 Elsevier B.V. All rights reserved.

Srobarova, A., A. Moretti, et al. (2002). "Toxigenic Fusarium species of Liseola section in pre-harvest maize ear rot, and associated mycotoxins in slovakia." European Journal of Plant Pathology 108(4): 299-306. ://000175803500003 The occurrence of Fusarium species of Liseola section and related toxins was investigated for two years (1996 and 1998) on maize ear rot samples collected in the most important areas for maize growing in Slovakia. The species most frequently isolated was F. verticillioides, followed by F. proliferatum in 1996 and F. subglutinans in 1998. Most of the strains belonged to mating populations A, D, and E of the teleomorph Gibberella fujikuroi. Fusarium graminearum was also frequently recovered in both the years of investigations. Toxin analysis of maize ears showed that most of the samples (21 out of 22) were contaminated with at least one toxin. In particular, the concentration of fumonisin B-1, and fumonisin (2) was up to 26.9 and 5.1 mug g(-1), respectively in 1996, and up to 12.1 and 6.3 mug g(-1), respectively in 1998. Beauvericin was detected only in one sample in 1996. Seven samples in 1996 were contaminated by fusaproliferin up to 8.2 mug g(-1), but just traces of the toxin were found in one sample in 1998. All 29 strains of F. verticillioides, two of three strains of F. proliferatum and none of eight F. subglutinans strains isolated from samples produced fumonisin B-1 in culture on whole maize kernels (0.1-5646 and 940-1200 muug g(-1), respectively). Two strains of F. subglutinans and two of F. proliferatum produced beauvericin (up to 65 and 70 mug g(-1), respectively). Ten strains of F. verticillioides produced beauvericin: 9 strains produced a low amount (up to 3 mug g(-1)), while only one of them produced a high level of toxin (375 mug g(- 1)). Fusaproliferin was produced by two F. proliferatum strains (220 and 370 mug g(-1)), by seven F. subglutinans (20-1335 mug g(- 1)) and by three F. verticillioides (10-35 mug g(-1)). This is the first report on fusaproliferin production by F. verticillioides, although at low level.

Staib, F., S. P. Hussain, et al. (2003). "TP53 and liver carcinogenesis." Human Mutation 21(3): 201-216. ://000181474900005 and http://www.botanischergarten.ch/Mycotoxins/Staib-Human-Mutation-2003.pdf Primary hepatocellular carcinoma (HCC) is one of the most common malignancies and has the fourth highest mortality rate worldwide. The major risk factors, including chronic infections with the hepatitis B or C virus, are exposure to dietary aflatoxin B-1 (AFB(1)), vinyl chloride, or alcohol consumption. Southern China and sub,Saharan Africa have the highest dietary AFB(1) exposure; making it and hepatitis B virus (HBV) the major causes of cancer mortality in these geographic areas. Recent studies have discovered genetic and epigenetic changes involved in the molecular pathogenesis of HCC, including somatic mutations in the p53 tumor suppressor gene (TP53). AFB(1) induces typical G:C to TA transversions at the third base in codon 249 of p53. Chronic active hepatitis B and C (HCV) infection, and further inflammatory and oxyradical disorders including Wilson disease (WD) or hemochromatosis, generate reactive oxygen/nitrogen species that can damage DNA and mutate the P53 gene. The X gene of HBV (HBx) is the most common open reading frame integrated into the host genome in HCC. The integrated HBx is frequently mutated and has a diminished ability to function as a transcriptional cotransactivator and to activate the NF-kappa B pathway. However, the mutant HBx proteins still retain their ability to bind to and abrogate p53-mediated apoptosis. In summary, both viruses and chemicals are implicated in the etiology and molecular pathogenesis of HCC. The resultant molecular changes in the ras and Wnt signal,transduction pathways, and the p53 and Rb tumor suppressor pathway's significantly contribute to liver carcinogenesis.

Stewart, D. W., L. M. Reid, et al. (2002). "A mathematical simulation of growth of Fusarium in maize ears after artificial inoculation." Phytopathology 92(5): 534-541. ://000175140800010 Fusarium spp. in maize can contaminate the grain with mycotoxins if environmental conditions are favorable for fungal growth. To quantify the relationship between growth of Fusarium spp. and environmental conditions, a mathematical model was developed to simulate growth of F. graminearum and F. verticillioides on maize ears following silk inoculation in field experiments from 1992 to 1995. Each species was inoculated separately and as a mixture of the two for 3 of the 4 years on one maize hybrid. Disease progress in cars was measured by a visual rating scale that was converted to percent visual infection. Measurements were made at regular time intervals after silks were inoculated 5 days after silk emergence. Differential equations were used to relate growth rates of Fusarium spp. in maize cars to hourly air temperature and relative humidity and to daily precipitation. Integration of these equations over time produced quantitative estimates of fungal growth. Model calculations compared well with measurements (R-2 = 0.931, standard error of estimate [SEE] = 2.11%) of percent visual disease infection of maize cars over 3 years. The model was tested against a second set of data (R-2 = 0.89, SEE = 5.9%) in which silks were inoculated at nine different times after first silk emergence for each of 2 years (1994 and 1995) with the two species of fungi on the same maize hybrid. At this time, a silk function was developed to account for changes in the susceptibility of silks to disease. F. graminearum responded to wet conditions more than F. verticillioides, and for the conditions of this experiment, grew much faster than F. verticillioides when inoculated separately. When they were inoculated together, F. graminearum growth rates were much lower, indicating some interference by F. verticillioides. During 1993, weather conditions before inoculation reduced the growth of both species in silks.

Stockenstrom, S., E. W. Sydenham, et al. (1998). "Fumonsin B-1, B-2, and B-3 content of commercial unprocessed maize imported into South Africa from Argentina and the USA during 1992." Food Additives and Contaminants 15(6): 676-680. ://000075577900007 The widespread occurence of F. moniliforme and the toxic effects of ifs secondary metabolites, the fumonisins B-1(FB1), B-2(FB2) and B-3(FB3), make it imperative that fumonisin contamination of maize, a major constituent of animal feed as well as the staple diet of many populations, be closely monitored to reduce the risk of fumonisin exposure. Equine leukoencephalomalacia and pol cine pulmonary oedema have been associated with the intake of feed heavily contaminated with fumonisins. In addition, high levels of fumonisins in the maize-based staple diets of cel tain populations have been linked to a high incidence of oesophageal cancel in the Transkei region of South Africa and in Linxian and Cixian Counties, China. Bulk shipments of maize imported into South Africa from the USA and Argentina during 1992 were sampled at the port of entry to determine fumonisin levels. Of the 79 samples from two US shipments, all were positive for fumonisins, with FB1 constituting approximately 71% of the total fumonisins with an overall mean of 2.35 mu g/gFB(1). The maximum FB1 level observed was 3.9 mu g/g. These levels contrast with those obtained from two Argentinian bulk: shipments, which also were all positive for fumonisins, but had a mean FB1 level of 0.31 mu g/g and a maximum observed level of 0.7 mu g/g FB1 measured over 47 composite samples.

Stoloff, L. (1967). "Collaborative Study of a Method for Identification of Aflatoxin B1 by Derivative Formation." Journal of the Association of Official Analytical Chemists 50(2): 354-&. ://WOS:A19679253000030

Stoloff, L. (1970). "Report on Mycotoxins." Journal of the Association of Official Analytical Chemists 53(2): 330-&. ://WOS:A1970F827700055

Stoloff, L. (1971). "Report on Mycotoxins." Journal of the Association of Official Analytical Chemists 54(2): 305-&. ://WOS:A1971J095700032

Stoloff, L. (1972). "Analytical Methods for Mycotoxins." Clinical Toxicology 5(4): 465-494. ://WOS:A1972O324000004

Stoloff, L. (1972). "Report on Mycotoxins." Journal of the Association of Official Analytical Chemists 55(2): 265-&. ://WOS:A1972M043500027

Stoloff, L. (1973). "Mycotoxins." Journal of the Association of Official Analytical Chemists 56(2): 278-282. ://WOS:A1973P247200027

Stoloff, L. (1974). "Report on Mycotoxins." Journal of the Association of Official Analytical Chemists 57(2): 274-278. ://WOS:A1974S430800028

Stoloff, L. (1975). "Report on Mycotoxins." Journal of the Association of Official Analytical Chemists 58(2): 213-217. ://WOS:A1975V936000027

Stoloff, L. (1976). "Occurrence of Mycotoxins in Foods and Feeds." Advances in Chemistry Series(149): 23-50. ://WOS:A1976BU41900002

Stoloff, L. (1976). "Report on Mycotoxins." Journal of the Association of Official Analytical Chemists 59(2): 317-323. ://WOS:A1976BM84000036

Stoloff, L. (1977). "Report on Mycotoxins." Journal of the Association of Official Analytical Chemists 60(2): 348-353. ://WOS:A1977CX81000037

Stoloff, L. (1978). "Report on Mycotoxins." Journal of the Association of Official Analytical Chemists 61(2): 340-346. ://WOS:A1978ET37200039

Stoloff, L. (1979). "Report on Mycotoxins." Journal of the Association of Official Analytical Chemists 62(2): 356-362. ://WOS:A1979GP24800049

Stoloff, L. (1980). "Aflatoxin Control - Past and Present." Journal of the Association of Official Analytical Chemists 63(5): 1067-1073. ://WOS:A1980KH85100021

Stoloff, L. (1980). "Aflatoxin-M in Perspective." Journal of Food Protection 43(3): 226-230. ://WOS:A1980JS52400016

Stoloff, L. (1987). "Carcinogenicity of Aflatoxins." Science 237(4820): 1283-1283. ://WOS:A1987J924400002

Stoloff, L. (1989). "Aflatoxin Is Not a Probable Human Carcinogen - the Published Evidence Is Sufficient." Regulatory Toxicology and Pharmacology 10(3): 272-283. ://WOS:A1989CD99900006 AND http://www.botanischergarten.ch/Bt/Stoloff-Aflatoxin-Not-a-Probable-Carcinogen-1989.pdf Since the early 1960s, when aflatoxin, the mold-produced contaminant of a number of important food commoditi4s, was found to be potent hepatocarcinogen for laboratory rats, there has been sustained search for evidence to support the regulatory presumption that aflatoxin is a probable human carcinogen. The developing laboratory evidence of differences between species in metabolism of aflatoxin and susceptibility to its oncogenic effects indicated that humans were probably refractory to aflatoxin carcinogenesis, but the early epidemiological evidence indicated otherwise. That epidemological evidence, however, contained flaws so that Working Groups of the International Agency for Research on Cancer (IARC) meeting in 1970, 1976 and 1882, although ignoring the biochemical evidence, did consider the available epidemiological evicdence insufficient for a conclusion of human carcinogenicity. During the 1970s and 1980s, studies on the connnection between chronic infection with hepatitis B virus (HBV) and Primary Liver cell Cancer (PLC), the expected lesion from aflatoxin exposure, had established a very strong etiological relationship between HBV and PLC. Since all the epidemiological studies of aflaxonxin and PLC conducted prior to 1982 had been of populations with endemic HBV infection, and, in additioin to other flaws, had not been controlled for this confounding factor, there was a solid basis for their rejection. Most epidemiolocial studies in the 1980s of aflatoxin and PLC were either in the United States, where HBV- infected groups could be excluded from the study, or, when in areas of chronic HBV infection, attempts were made to include that factor. The study of U.S. populations showed no difference in mortality rates from PLC that could be attributed to aflatoxin exposure. The studies of populations with endemic HBV infection produced no convincing evidence to suppoort a primary role for aflaxonxin could not be ruled out. However, the epidemiological studies of the HBV/PLC relation indicate that an accessory factor is not an essential condition, a conclusion supported by animal models and a laboratory study that specifically found no interaction between aflatoxin and a hepatitis virus in the duck, a species in which liver cancer can be induced by either agent. It was surprising that an IARC Working Group meeting in 1987 concluded, on the basis of much of this evidence that was available a that time, and citing other studies that appear to be irrelevant to the issue, that there was sufficient evidence to consider aflatoxin a probable human carcinogen.

Stoloff, L., A. D. Campbell, et al. (1969). "Sample Preparation for Aflatoxin Assay - Nature of Problem and Approaches to a Solution." Journal of the American Oil Chemists Society 46(12): 678-&. ://WOS:A1969F050300013

Stoloff, L. and B. Dalrymple (1977). "Aflatoxin and Zearalenone Occurrence in Dry-Milled Corn Products." Journal of the Association of Official Analytical Chemists 60(3): 579-582. ://WOS:A1977DG84500014

Stoloff, L., J. Dantzman, et al. (1971). "Aflatoxin Excretion in Wethers." Food and Cosmetics Toxicology 9(6): 839-&. ://WOS:A1971L150200006

Stoloff, L. and O. J. Francis (1980). "Survey for Aflatoxins and Zearalenone in Canned and Frozen Sweet Corn." Journal of the Association of Official Analytical Chemists 63(2): 180-181. ://WOS:A1980JQ01300007

Stoloff, L., S. Henry, et al. (1976). "Survey for Aflatoxins and Zearalenone in 1973 Crop Corn Stored on Farms and in Country Elevators." Journal of the Association of Official Analytical Chemists 59(1): 118-121. ://WOS:A1976BG64100026

Stoloff, L., S. Nesheim, et al. (1971). "Multimycotoxin Detection Method for Aflatoxins, Ochratoxins, Zearalenone, Sterigmatocystin, and Patulin." Journal of the Association of Official Analytical Chemists 54(1): 91-&. ://WOS:A1971I412400022

Stoloff, L., M. Trucksess, et al. (1975). "Stability of Aflatoxin-M in Milk." Journal of Dairy Science 58(12): 1789-1793. ://WOS:A1975BB51500003

Stoloff, L. and M. W. Trucksess (1978). "Survey for Aflatoxin B-1 in Chicken Eggs." Journal of the Association of Official Analytical Chemists 61(4): 995-996. ://WOS:A1978FJ37400042

Stoloff, L. and M. W. Trucksess (1979). "Distribution of Aflatoxin-B1 and Aflatoxin-M1 in Contaminated Calf and Pig Livers." Journal of the Association of Official Analytical Chemists 62(6): 1361-1362. ://WOS:A1979HV16700031

Stoloff, L. and M. W. Trucksess (1981). "Effect of Boiling, Frying, and Baking on Recovery of Aflatoxin from Naturally Contaminated Corn Grits or Cornmeal." Journal of the Association of Official Analytical Chemists 64(3): 678-680. ://WOS:A1981LR11200025

Stoloff, L., H. P. Vanegmond, et al. (1991). "Rationales for the Establishment of Limits and Regulations for Mycotoxins." Food Additives and Contaminants 8(2): 213-222. ://WOS:A1991FP37500009 Although 50 countries have enacted or proposed regulations for control of aflatoxins in food or feed, and 15 of these countries also have regulations for permitted levels of contamination by other mycotoxins, very few countries have formally presented the rationale for the need to regulate, or for the selection of a particular maximum tolerated level. After several successive inquiries, information concerning the rationale for regulation was obtained from 21 countries. Most of the responses concerned limits for aflatoxin in food, and most of these were based on a vague, unsupported statement of the carcinogenic risk for humans. There was a general consensus that exposure to a potential human carcinogen that could not be totally avoided should be limited to the lowest practical level; the definition of practicality depended on whether the country was an importer or producer of the potentially contaminated commodity. A claim to a hazard evaluation was made by six countries (Canada, Belgium, India, United Kingdom, United States, Switzerland) without providing specifics; and one country, South Africa, referred to a risk determination. The most comprehensive rationale for any mycotoxin regulation was provided by the United States in support of limits for aflatoxin in specific animal feedstuffs. The responses provided no rationale for setting limits for other mycotoxins; but scholarly risk assessments for zearalenone and ochratoxin A have been published by Canadian government scientists, and a symposium presentation provides the information that in Norway patulin is regulated for quality control purposes only. It is apparent that, in most countries, either the scientific basis for regulation of mycotoxins is nonexistent, or the science has not been fully utilized. For a common approach to the control of mycotoxin hazards, access to the best available scientific data, and agreement on its interpretation, now appear to be the most important initial steps.

Stoloff, L., M. J. Verrett, et al. (1972). "Toxicological Study of Aflatoxin P, Using Fertile Chicken Egg." Toxicology and Applied Pharmacology 23(3): 528-&. ://WOS:A1972N817900019

Stoloff, L., G. Wood, et al. (1981). "Aflatoxin M1 in Manufactured Dairy-Products Produced in the United-States in 1979." Journal of Dairy Science 64(12): 2426-2430. ://WOS:A1981NC27400016

Stubblefield, R. D., W. F. Kwolek, et al. (1982). "Determination and Thin-Layer Chromatographic Confirmation of Identity of Aflatoxin-B1 and Aflatoxin-M1 in Artificially Contaminated Beef Livers - Collaborative Study." Journal of the Association of Official Analytical Chemists 65(6): 1435-1444. ://WOS:A1982PR43700028

Sydenham, E. W., W. C. A. Gelderblom, et al. (1990). "Evidence for the Natural Occurrence of Fumonisin-B1, a Mycotoxin Produced by Fusarium-Moniliforme, in Corn." Journal of Agricultural and Food Chemistry 38(1): 285-290. ://A1990CK49600064

Sydenham, E. W., W. F. O. Marasas, et al. (1992). "Fumonisin Concentrations in Brazilian Feeds Associated with Field Outbreaks of Confirmed and Suspected Animal Mycotoxicoses." Journal of Agricultural and Food Chemistry 40(6): 994-997. ://A1992HZ93700016 AND http://www.botanischergarten.ch/Bt/Sydenham-Fumonisin-Brazil-1992.pdf Twenty-one Fusarium moniliforme-contaminated feed samples associated with outbreaks of confirmed and suspected mycotoxicoses in various animal species were collected from farms in the State of Parana, Brazil, and analyzed for the fumonisins. Fumonisins B1 (FB1) and B2 (FB2) were detected in 20 and 18 of the 21 feed samples, respectively, at concentrations of 0.2-38.5-mu- g g-1 FB1 and 0.1-12.0-mu-g g-1 FB2. In addition, duckling toxicity and fumonisin levels were determined in com cultures of 26 F. moniliforme isolates from the feed samples. With the exception of one isolate, all were acutely toxic to ducklings and contained 65- 4420-mu-g g-1 FB1 and 5-1380-mu-g g-1 FB2. The results constitute the first report on the natural occurrence of the fumonisins in animal feeds from Brazil.

Sydenham, E. W., W. F. O. Marasas, et al. (1991). "Production of Mycotoxins by Selected Fusarium-Graminearum and F-Crookwellense Isolates." Food Additives and Contaminants 8(1): 31-41. ://A1991EU69900004 Corn cultures (five isolates each of Fusarium graminearum Group 1 from wheat crowns, Group 2 from scabby wheat grains and from ear rot of corn and five isolates of F. crookwellense) were screened for their ability to produce deoxynivalenol (DON), nivalenol (NIV), fusarenon-x (FUS-X) and zearalenone (ZEA). Nine of the ten F. graminearum isolates from wheat produced DON (5-165-mu-g g-1) but none produced either NIV or FUS-X. Conversely, 3/5 and 2/5 of the F. graminearum isolates from corn produced NIV (5-40- mu-g g-1) and FUS-X (5-7-mu-g g-1), respectively, while none produced DON. All but one of the F. graminearum isolates produced ZEA (2-1160-mu-g g-1). None of the F. crookwellense isolates produced DON, but 5/5 and 4/5 produced NIV (6-170-mu-g g-1) and FUS-X (3-90-mu-g g-1), respectively, and all produced ZEA (605-1030-mu-g g-1). The results confirmed previous findings on the presence of two distinct F. graminearum chemotypes.

Sydenham, E. W., G. S. Shephard, et al. (1997). "Production of fumonisin B analogues and related compounds by Fusarium globosum, a newly described species from corn." Journal of Agricultural and Food Chemistry 45(10): 4004-4010. ://A1997YB39700053 Fusarium globosum Rheeder, Marasas et Nelson is a recently described species originally isolated from corn kernels harvested in the Transkei region of South Africa. On the basis of morphological criteria, F. globosum is closely related to other common fungal contaminants of corn, viz. F. moniliforme, F. proliferatum, and F. subglutinans, and accordingly it has been classified in the section Liseola. Species within the section Liseola have been reported to produce either the fumonisin B or moniliformin (MON) mycotoxins and, in some cases both. Seventeen isolates off. globosum, cultured on corn, were screened for the production of fumonisins B-1 (FB1), B-2 (FB2), B-3 (FB3), and MON. All isolates produced FB1 (range 5-325 mu g/g), while 15 of 17 also produced FB2 (range 1-4 mu g/g). For 14 of 17 isolates, the levels of FB3 produced (range 4-24 mu g/g) exceeded those of the corresponding FB2 concentrations. None of the isolates produced detectable levels of MON (< 1 mu g/g). In addition, several isolates of F. globosum also produced two additional fumonisin-like compounds, the mass spectral evidence of which suggests that they may be isomers of FB1 and FB2 or FB3, respectively.

Sydenham, E. W., G. S. Shephard, et al. (1992). "Liquid-Chromatographic Determination of Fumonisin-B1, Fumonisin-B2, and Fumonisin-B3 in Foods and Feeds." Journal of Aoac International 75(2): 313-318. ://A1992HM21600016 Three recently described and toxicologically important Fusarium mycotoxins, fumonisin B1 (FB1), fumonisin B2 (FB2), and fumonisin B3 (FB3), are the major fumonisins produced in cultures of F. moniliforme, a fungus that occurs worldwide on corn. Contamination of food and feed with F. moniliforme has been associated with a number of diseases in both animals and humans. Aspects of a recently reported liquid chromatographic method for the determination of FB1 and FB2 in corn, including initial extraction, extract purification, and stability of derivatives, were investigated and, where necessary, optimized further both to reduce the analysis time and to include the co- determination of FB3. The method was applied for the determination of FB3, in a series of U.S. feed samples associated with outbreaks of equine leukoencephalomalacia, which were shown previously to contain both FB1 and FB2. Twelve of the 13 feed samples contained FB3 at levels ranging between 50 and 2650 ng/g, corresponding to 2.2-18% of the total fumonisin concentrations present in the FB3-positive feed samples. This is the first report of the natural occurrence of FB3.

Sydenham, E. W., G. S. Shephard, et al. (1996). "Determination of fumonisins in corn: Evaluation of competitive immunoassay and HPLC techniques." Journal of Agricultural and Food Chemistry 44(1): 159-164. ://A1996TR36000029 The fumonisins, mycotoxins produced by Fusarium moniliforme, are known to occur as natural contaminants of corn worldwide and to be associated with several animal disease syndromes. Highperformance liquid chromatography (HPLC) and monoclonal antibody- based (MAb) competitive direct enzyme-linked immunosorbent assay (CD-ELISA) methods, developed for the determination of fumonisins in corn, were compared. CD-ELISA results for naturally contaminated corn were consistently higher than corresponding HPLC results. Quantitative differences were reduced by decreasing the organic phase composition of the extract and by introducing a hexane partitioning step. The results were indicative of a possible lipid-based matrix effect, but when applied to fumonisin-free corn spiked with fumonisin levels ranging from 0.8 to 12.8 mu g/g, analyses by both techniques were well correlated (r = 0.996). It is concluded that structurally related fumonisin- like compounds, present in naturally contaminated corn, may contribute to the differences recorded between the two methods, although the MAb-based CD-ELISA may still be used as an initial semiquantitative screening technique.

Sydenham, E. W., G. S. Shephard, et al. (1993). "Fumonisins in Argentinean Field-Trial Corn." Journal of Agricultural and Food Chemistry 41(6): 891-895. ://A1993LH11900010 Seventeen corn samples, which formed part of a series of field trials conducted in Argentina, were analyzed for fumonisins B1 (FB1), B2(FB2), and B3 (FB3). Combined fumonisin concentrations recorded in the samples ranged between 1585 and 9990 ng g-1, The bulk of the samples (16/17) had combined fumonisin levels in excess of 2000 ng g-1, with several having levels previously shown to be associated without breaks of equine leukoencephalomalacia. In addition, several isolates of Fusarium moniliforme and Fusarium proliferatum of Argentinian origin were analyzed to determine their fumonisin-producing ability. FB1 was the major fumonisin analogue produced by the F. moniliforme isolates (50-8160 mug g-1), but for each isolate, production levels of FB3 exceeded the corresponding FB2 levels. One of the three F. proliferatum isolates produced only FB2. The data represent the first reports of the natural occurrence of the three major fumonisin analogues in Argentinian corn and the production of fumonisins by Fusarium isolates from Argentina.

Sydenham, E. W., G. S. Shephard, et al. (1991). "Fumonisin Contamination of Commercial Corn-Based Human Foodstuffs." Journal of Agricultural and Food Chemistry 39(11): 2014-2018. ://A1991GQ61400028 and http://www.botanischergarten.ch/Mycotoxins/Sydenham-Fumonisin-1991.pdf Corn-based human foodstuffs from retail outlets in five countries were analyzed for fumonisin B1 (FB1) and fumonisin B2 (FB2). The highest mean concentrations occurred in two Egyptian samples (2380 ng/g FB1 and 595 ng/g FB2). Only one of four Peruvian samples contained 660 ng/g FB1 and 68 ng/g FB2, while only one of two Canadian samples contained a detectable level of FB1. The 16 cornmeal (CM) and 10 corn grits (CG) products from the United States contained mean concentrations of 1048 ng/g FB1 and 298 ng/g FB2 and 601 ng/g FB1 and 375 ng/g FB2, respectively, while the mean concentrations in 52 CM and 18 CG samples from South Africa were 138 ng/g FB1 and 83 ng/g FB2 and 125 ng/g FB1 and 85 ng/g FB2, respectively. Only 1 of 10 cornflakes/lime-treated samples contained a low level of FB1. Of several samples obtained from a high esophageal cancer (EC) risk area in the United States 7/7 contained FB1 (105-1915 ng/g) and 6/7 FB2 (70-460 ng/g).

Sydenham, E. W., G. S. Shephard, et al. (1996). "Liquid chromatographic determination of fumonisins B-1, B-2, and B-3 in corn: AOAC-IUPAC collaborative study." Journal of Aoac International 79(3): 688-696. ://A1996UN11000012 A liquid chromatographic (LC) method for simultaneous determination of fumonisins B-1 (FB1), B-2 (FB2), and B-3 (FB3) in corn was subjected to a collaborative study involving 12 participants from 10 countries, in which the accuracy and reproducibility characteristics of the method were established, Mean analyte recoveries from corn ranged from 81.1 to 84.2% for FB1 (at a spiking range of 500 to 8000 ng/g), from 75.9 to 81.9% for FB2 (at a spiking range of 200 to 3200 ng/g), and from 75.8 to 86.8% for FB3 (at a spiking range of 100 to 1600 ng/g), The valid data were statistically evaluated after exclusion of outliers. Relative standard deviations for within- laboratory repeatability ranged from 5.8 to 13.2% for FB1, from 7.2 to 17.5% for FB2, and from 8.0 to 17.2% for FB3, Relative standard deviations for between-laboratory reproducibility varied from 13.9 to 22.2% for FB1, from 15.8 to 26.7% for FB2, and from 19.5 to 24.9% for FB3. HORRAT ratios, calculated for the individual toxin analogues, ranged from 0.75 to 1.73, The LC method for determination of fumonisins B-1, B-2, and B-3 in corn (at concentrations of 800-12800 ng total fumonisins/g) has been adopted by AOAC INTERNATIONAL.

Sydenham, E. W., S. Stockenstrom, et al. (1996). "Polyclonal antibody-based ELISA and HPLC methods for the determination of fumonisins in corn: A comparative study." Journal of Food Protection 59(8): 893-897. ://A1996VD34600019 The performance of an experimental polyclonal antibody (PAb)- based competitive direct enzyme-linked immunosorbent assay (CD- ELISA) developed for the analysis of fumonisins in corn was assessed by comparison with an established highperformance liquid chromatography (HPLC) method. The comparative study was conducted using a series of 20 corn samples naturally contaminated with combined fumonisin levels ranging from <0.05 to >5 mu g/g (ppm). Linear regression analysis between the results generated by HPLC and CD-ELISA provided correlation coefficients (r) and regression slopes (b) of r = 0.960, b = 1.493 (P < 0.001); r = 0.865, b = 3.903 (P < 0.001); and r = 0.832, b = 0.107 (P < 0.001) for the individual fumonisins B-1 (FB1), B-2 (FB2) and B-3 (FB3), respectively, while corresponding values of r = 0.967, b = 1.059 (P < 0.001) were obtained for the combined FB1, FB2, and FB3 concentrations. In 3 of 18 fumonisin-positive corn samples, combined fumonisin levels determined by CD-ELISA were between 85 and 100% higher than those determined in the same extracts by HPLC, while in 13 other samples, CD-ELISA results were between 1.8 and 53% higher than those determined by HPLC. Conversely, in 2 of 18 samples, CD-ELISA results were lower than those determined by HPLC. The differences recorded between HPLC and the experimental PAb- based CD-ELISA were far less than those previously recorded for other mono- and polyclonal antibody-based CD-ELISA systems. The results indicate that the experimental PAb-based. CD-ELISA may be effectively applied for the initial screening for fumonisins in corn.

Sydenham, E. W., S. Stockenstrom, et al. (1995). "Potential of Alkaline-Hydrolysis for the Removal of Fumonisins from Contaminated Corn." Journal of Agricultural and Food Chemistry 43(5): 1198-1201. ://A1995QY97800014 Studies have shown that fumonisin B-1 (FB1) may undergo alkaline hydrolysis to yield its aminopentol (AP(1)) and tricarballylic acid moieties. Treatment of fumonisin- contaminated ground corn with 0.1 M calcium hydroxide, over a period of 24 h at room temperature, resulted in the transfer of the majority of the FB1 (mean = 74.1%) to the easily separable aqueous fraction, where it was present predominantly as the AP(1) moiety. Following similar treatment of intact corn kernels, only 5.1% of the original FB1 concentration was retained in those kernels devoid of their outer pericarp.

Sydenham, E. W., P. G. Thiel, et al. (1990). "Natural Occurrence of Some Fusarium Mycotoxins in Corn from Low and High Esophageal Cancer Prevalence Areas of the Transkei, Southern Africa." Journal of Agricultural and Food Chemistry 38(10): 1900-1903. ://A1990EE50900004

Sydenham, E. W., P. G. Thiel, et al. (1995). "Preparation and Isolation of the Partially Hydrolyzed Moiety of Fumonisin B-1." Journal of Agricultural and Food Chemistry 43(9): 2400-2405. ://A1995RW08900016 The natural occurrence in corn of carcinogenic mycotoxins, the fumonisins, has prompted the development of potential decontamination procedures. Chemical treatment of fumonisin B-1 (FB1)-contaminated corn with calcium hydroxide [Ca(OH)(2)] results in the base hydrolysis of FB1 (the major naturally occurring fumonisin analogue) to yield its corresponding aminopentol (AP(1)) and tricarballylic acid (TCA) moieties. Complete hydrolysis proceeds in a sequential reaction involving the removal of one TCA group and the formation of a partially hydrolyzed moiety (PH1), which exists as an equilibrium mixture of the two possible monoesters. PH1 was prepared by the treatment of Fusarium moniliforme culture material with Ca(OH)2 and subsequently isolated and purified using chromatographic methods. PH1 was also prepared, using similar methods, from pure FB1. The identity of the PH1 moiety was determined by liquid chromatography-electrospray mass spectrometry.

Sydenham, E. W., P. G. Thiel, et al. (1996). "Physicochemical data for some selected Fusarium toxins." Journal of Aoac International 79(6): 1365-1379. ://A1996VU05000018 Fusarium toxins are a major group of secondary metabolites, produced by several species, that may contaminate food cereals and animal feeds, We describe results of a study in which a number of physicochemical constants for 12 important Fusarium mycotoxins (zearalenone, diacetoxyscirpenol, T-2 toxin, neosolaniol monoacetate, deoxynivalenol, nivalenol, fumonisin B-1, fumonisin B-2, moniliformin, fusarenon-X, HT-2 toxin, and beta-zearalenol) were determined, Nuclear magnetic resonance, mass spectrometric, UV spectral, molar absorption coefficients, fluorescence spectra, melting points, and specific rotation data are presented.

Sydenham, E. W., L. Vanderwesthuizen, et al. (1994). "Fumonisin-Contaminated Maize - Physical Treatment for the Partial Decontamination of Bulk Shipments." Food Additives and Contaminants 11(1): 25-32. ://A1994MY76800004 Ten maize samples, randomly selected from a bulk shipment imported into South Africa, were characterized by a wide distribution in particulate size. Following fractionation by sieving through a 3 mm screen, the 'kernels' (fractions greater-than-or-equal-to 3 mm) corresponding to between 80.0 and 95-3% of the samples by mass, were contaminated with total fumonisin levels of between 530 and 1890 ng/g. Conversely, those fractions termed 'fines' (< 3 mm) had significantly higher total fumonisin concentrations of between 12 340 and 27 460 ng/g, and accounted for between 4.7 and 20.0% of the samples by mass. The data indicated that removal of the 'fines' resulted in overall reductions in total fumonisin levels of between 26.2 and 69.4%. It is suggested that initial removal of 'fines' from bulk shipments of maize, prior to further processing, could be considered as a preliminary fumonisin- decontamination procedure.

Takahashi, T., P. K. Chang, et al. (2002). "Nonfunctionality of Aspergillus sojae aflR in a strain of Aspergillus parasiticus with a disrupted aflR gene." Applied and Environmental Microbiology 68(8): 3737-3743. ://000177260500010 Aspergillus sojae belongs to the Aspergillus section Flavi but does not produce aflatoxins. The functionality of the A. sojae aflR gene (aflRs) was examined by transforming it into an DeltaaflR strain of A. parasiticus, derived from a nitrate- nonutilizing, versicolorin A (VERA)-accumulating strain. The A. parasiticus aflR gene (aflRp) transformants produced VERA, but the aflRs transformants did not. Even when aflRs was placed under the control of the amylase gene (amyB) promoter of Aspergillus oryzae, the amy(p)::aflRs transformants did not produce VERA. A chimeric construct containing the aflRs promoter plus the aflRs N- and aflRp C-terminal coding regions could restore VERA production, but a construct containing the aflRp promoter plus the aflRp N- and aflRs C-terminal coding regions could not. These results show that the A. sojae aflR promoter is functional in A. parasiticus and that the HAHA motif does not affect the function of the resulting hybrid AflR. We conclude that the lack of aflatoxin production by A. sojae can be attributed, at least partially, to the premature termination defect in aflRs, which deletes the C-terminal transcription activation domain that is critical for the expression of aflatoxin biosynthetic genes.

Tam, J., M. Mankotia, et al. (2006). "Survey of breakfast and infant cereals for aflatoxins B-1, B-2, G(1) and G(2)." Food Additives and Contaminants 23(7): 693-699. ://WOS:000238201000007 Three hundred and forty-nine breakfast and infant cereal samples were collected at retail level across Canada from 2002 to 2005. They included rice-, soy-, barley-based and mixed-grain infant cereals, corn-, wheat-, rice-based and mixed-grain breakfast cereals, and were analysed for aflatoxins B-1, B-2, G(1) and G(2) using a modified AOAC International official method. An immunoaffinity column was used for the cleanup and purification of extracts. Determination of aflatoxins was by LC using post-column derivatization with pyridinium hydrobromide perbromide and fluorescence detection. Results indicated that 50% of both breakfast and infant cereals had detectable levels (limit of detection = 0.002 ng g(-1)) of aflatoxin B-1, which is the most toxic of the four toxins. The levels found varied from 0.002 to 1.00 ng g(-1) for aflatoxin B-1, from 0.002 to 0.14 ng g(-1) for aflatoxin B-2, from 0.008 to 0.27 ng g(-1) for aflatoxin G(1), and from 0.008 to 0.048 ng g(-1) for aflatoxin G(2). Only 4% of the breakfast cereals and 1% of the infant cereals had aflatoxin B1 levels exceeding 0.1 ng g(-1), which is the European Union maximum limit for aflatoxin B1 in baby foods and processed cereal-based foods for infants and young children.

Tarter, E. J., J. P. Hanchay, et al. (1984). "Improved Liquid-Chromatographic Method for Determination of Aflatoxins in Peanut Butter and Other Commodities." Journal of the Association of Official Analytical Chemists 67(3): 597-600. ://WOS:A1984SU63000032

Theumer, M. G., A. G. Lopez, et al. (2003). "Immunobiological effects of AFB1 and AFB1-FB1 mixture in experimental subchronic mycotoxicoses in rats." Toxicology 186(1-2): 159-170. ://000181732800015 Maize co-contamination with aflatoxin B1 (AFB1) and fumonisin B1 (FB1) is frequently found in several countries. Although the alterations on nutritional and immunologic parameters induced by these mycotoxins, when administered individually, are partially characterised, little is known about the effects induced in animals by a subchronic administration of both toxins mixtures. We have studied the nutritional and immunological alterations induced in rats fed during 90 days with a diet without mycotoxins, containing 40 ppb AFB1, and with a diet containing a mixture of 40 ppb AFB1 and 100 ppm FB1. Animals fed with the mixture of toxins obtained lower body weight than the control ones. The mitogenic response of spleen mononuclear cells (SMC) in vivo was higher in animals fed with AFB1. In in vitro studies, lower proliferations of SMC pre- exposed to AFB1 and to the mixture of toxins were detected. The SMC of animals fed with AFB1 produced lower levels of IL-2, higher of IL-4 and equal levels of IL-10. The SMC of animals fed with both toxins produced higher levels of IL-4, lower of IL-10 and equal levels of IL-2. The SMC preincubated with an AFB1-FB1 mixture produced higher concentrations of IL-4, lower of IL-10 and equal levels of IL-2. The peritoneal macrophages of animals that consumed AFB1 released less H2O2, while animals fed with the mixture of toxins produced higher levels. In in vitro studies, macrophages pre-exposed to the mixture of toxins released less H2O2. These results show different immunobiological effects produced by a mixture of mycotoxins in comparison to the individual action of the same toxins. (C) 2002 Published by Elsevier Science Ireland Ltd.

Thiel, P. G., W. F. O. Marasas, et al. (1992). "The Implications of Naturally-Occurring Levels of Fumonisins in Corn for Human and Animal Health." Mycopathologia 117(1-2): 3-9. ://A1992HL60100002 AND NEBIS 20080204 Contamination of corn with the fungus Fusarium moniliforme and its secondary metabolites, the fumonisins, has been associated with several human and animal diseases. This paper summarizes present knowledge and presents new data on the levels of fumonisins present in foods and feeds associated with these diseases as well as in commercial corn and corn-based products. The doses of fumonisins to which humans and animals consuming these products would be exposed are compared with those doses known to produce LEM in horses and hepatocarcinogenesis in rats. It is concluded that the known naturally occurring levels of fumonisins present a potential threat to human and animal health and realistic tolerance levels need to be set.

Thiel, P. G., W. F. O. Marasas, et al. (1991). "Survey of Fumonisin Production by Fusarium Species." Applied and Environmental Microbiology 57(4): 1089-1093. ://A1991FF03900032 Fumonisins B1 (FB1) and B2 (FB2), two structurally related mycotoxins with cancer-promoting activity, were recently isolated from corn cultures of Fusarium moniliforme MRC 826. These toxins have been reported to be produced also by isolates of F. proliferatum. Contamination of foods and feeds by F. moniliforme has been associated with human esophageal cancer risk, and FB1 has been shown to be the causative agent of the neurotoxic disease leukoencephalomalacia in horses. Because of the toxicological importance of the fumonisins, the potential to produce FB1 and FB2 was determined in a study of 40 toxic Fusarium isolates representing 27 taxa in 9 of the 12 sections of Fusarium, as well as two recently described species not yet classified into sections. With the exception of one isolate of F. nygamai, fumonisin production was restricted to isolates of F. moniliforme and F. proliferatum, in the section Liseola. The F. nygamai isolate produced 605-mu-g of FB1 g-1 and 530-mu- g of FB2 g-1, and the identity of the toxins was confirmed by capillary gas chromatography-mass spectrometry. This is the first report of the production of the fumonisins by F. nygamai.

Thiel, P. G., G. S. Shephard, et al. (1991). "Levels of Fumonisin-B1 and Fumonisin-B2 in Feeds Associated with Confirmed Cases of Equine Leukoencephalomalacia." Journal of Agricultural and Food Chemistry 39(1): 109-111. ://A1991ET70500022 AND http://www.botanischergarten.ch/Bt/Thiel-Level-Fumonisins-1991.pdf Leukoencephalomalacia (LEM) is a neurotoxic disease of Equidae caused by the ingestion of feed contaminated with the fungus Fusarium moniliforme. Feed samples from the United States that were fed to horses prior to the development of LEM were analyzed for fumonisin B1 (FB1) and fumonisin B2 (FB2), toxic secondary metabolites of F. moniliforme. In addition, FB1, FB2, and moniliformin were determined in corn cultures of 10 isolates of F. moniliforme from these samples. None of the cultures produced moniliformin but all contained both FB1 (160- 3800-mu-g g-1) and FB2 (20-950-mu-g g-1). All 14 feed samples contained both FB1 (1.3-27.0-mu-g g-1) and FB2 (0.1-12.6-mu-g g-1). FB1 was the major fumonisin in the cultures (80-96%) as well as in the feed samples (53-93%). These results support the finding that the fumonisins are causative factors in the development of LEM in horses.

Thiel, P. G., E. W. Sydenham, et al. (1995). "The Reliability and Significance of Analytical Data on the Natural Occurrence of Fumonisins in Foods and Feeds." Abstracts of Papers of the American Chemical Society 209: 101-AGFD. ://A1995QP23200101

Thiel, P. G., E. W. Sydenham, et al. (1993). "Study of the Reproducibility Characteristics of a Liquid- Chromatographic Method for the Determination of Fumonisins B-1 and B-2 in Corn - Iupac Collaborative Study." Journal of Aoac International 76(2): 361-366. ://A1993KT99000017 An interlaboratory study of the reproducibility characteristics of a liquid chromatographic method for the determination of fumonisins B1 and B2 in corn was conducted in 11 laboratories in the United States, South Africa, Italy, Japan, United Kingdom, and The Netherlands. Each laboratory was supplied with 12 coded, blind duplicates of 6 samples of naturally contaminated corn containing different amounts of fumonisins B1 and B2. Samples are extracted with methanol-water (3 + 1), extracts are centrifuged, and supernatants are cleaned up on strong-anion-exchange cartridges, which were supplied to participants. Solutions are derivatized with o- phthaldialdehyde, and individual fumonisins are determined by reversed-phase liquid chromatography with fluorescence detection. Quantitation is by comparison with the supplied fumonisin standards. The within-laboratory repeatability was determined by statistical analysis of data after exclusion of outliers. Relative standard deviations for within-laboratory repeatability varied from 7.7 to 25.5% for fumonisin B1 at concentrations between 200 and 2000 ng/g and from 12.5 to 36.8% for fumonisin B2 at concentrations between 70 and 740 ng/g. Relative standard deviations for between-laboratory reproducibility varied from 18.0 to 26.7% for fumonisin B1 and from 28.0 to 45.6% for fumonisin B2 at the concentrations mentioned above. These measures of variability indicate that the method is suitable for adoption as an official method provided that the accuracy characteristics are verified collaboratively.

Thirumala-Devi, K., M. A. Mayo, et al. (2002). "Occurrence of aflatoxins and ochratoxin A in Indian poultry feeds." Journal of Food Protection 65(8): 1338-1340. ://000177228500022 AND http://www.botanischergarten.ch/Bt/Thirumala-Devi-Occurrence-Aflatoxins-2002.pdf From 1998 to 2001, 216 ingredients intended for incorporation into chicken feed, which included groundnut cake, maize, millets, rice bran. sorghum, soybean, sunflower, and mixed feeds, were assayed for aflatoxins and ochratoxin A contamination using an indirect competitive enzyme-linked immunosorbent assay. Thirty-eight percent of the sample,, were contaminated With aflatoxins and 6% with ochratoxin A. The incidence scores of aflatoxin contamination in excess of 10 mug/kg were 41 of 95 for maize, 18 of 30 for mixed feeds. 10 of 37 for groundnut 6 of 29 for sorghum, 5 of 10 for sunflower, 3 of 14 for rice bran, and 1 of 8 for millet. Ochratoxin A contamination, in excess of 10 mug/kg, was found in 9 of 29 sorghum samples, 1 of 27 groundnut samples, 1 of 14 rice bran samples, 1 of 10 sunflower samples. and 2 of 8 millet samples. Ochratoxin A was not found in maize and mixed feeds. None of the three soybean samples contained ochratoxin A. This is the first report, to our knowledge. of co-occurrence of aflatoxins and ochratoxin A in 1ndian poultry feeds, The results confirm the importance of analysis of ingredients before incorporating them into mixed feeds.

Thirumala-Devi, K. and D. Reddy (2004, 2004). "Application of ELISA for cost-effective analysis of aflatoxins in foods and feeds." FoodInfo Online Features. from http://www.botanischergarten.ch/Mycotoxins/Thirumala-Mycotox-Info-Food-2004.pdf. Agricultural commodities are often vulnerable to attack by fungi that are able to produce toxic metabolites called mycotoxins. Among the various mycotoxins, aflatoxins have assumed significance due to their deleterious effects on humans, poultry and livestock and their role in carcinogenesis and immunosuppression. Simple and cost-effective methods for determining aflatoxin levels in various commodities are extremely important. In addition to such methods being used by commercial companies, research institutes and farmers, they are indispensable during risk assessment analyses and for determining the suitability of agricultural commodities for international trade. This paper describes the application of various forms of enzyme-linked immunosorbent assay (ELISA), and their merits for the estimation of aflatoxins in foods and feeds. A cost-effective penicillinase-based ELISA is described and the reliability of ELISA techniques, as compared with other methods of evaluating aflatoxins, are outlined

Torres, A. M., M. L. Ramirez, et al. (2003). "Potential use of antioxidants for control of growth and fumonisin production by Fusarium verticillioides and Fusarium proliferatum on whole maize grain." International Journal of Food Microbiology 83(3): 319-324. ://000183055800008 The effect of interactions between two food grade antioxidants butylated hydroxyanisole (BHA) and propyl paraben (PP, 100, 200, 500 mug g(-1)) and water activity (a(w), 0.995, 0.98, 0.95) of irradiated maize on lag phase prior to growth, growth rate and fumonisin production by Fusarium verticillioides and Fusarium proliferatum was evaluated at 25 degreesC. Both antioxidants had an effect on growth characteristics, and fumonisin production. However, this was dependent on the dose used and the a, treatment. At 500 mug g(-1) BHA and PP increased the lag phase prior to growth, and reduced the growth rate of both Fusarium species significantly, especially at 0.95 aw. Both antioxidants significantly reduced the production of fumonisin by both Fusarium species, especially at 0.98 and 0.95 a,. These results suggest that these antioxidants have potential for treatment of maize grain for controlling growth of these mycotoxigenic species and prevent fumonisin accumulation. (C) 2002 Elsevier Science B.V. All rights reserved.

Torres, A. M., M. M. Reynoso, et al. (2001). "Fusarium species (section Liseola) and its mycotoxins in maize harvested in northern Argentina." Food Additives and Contaminants 18(9): 836-843. ://000170526100009 Maize and maize products harvested in small fields and stored by farmers in northern Argentina were assayed for Fusarium and fumonisin and beauvericin contamination. Fumonisins were present in six of the 18 samples. The levels of fumonisins ranged from 603 to 1888 ng/kg. Fumonisin B-3 (FB3) and beauvericin were not detected in the samples evaluated. Fusarium subglutinans was one of the most prevalent species isolated. Twenty-five strains of F. subglutinans isolated from maize kernels and belonging to Gibberella fujikuroi mating population E were beauvericin-producers in culture. Seven of these strains also produced moniliformin. This is the first report on beauvericin-production by maize isolates of F. subglutinans from Argentina.

Trager, W. and L. Stoloff (1967). "Possible Reactions for Aflatoxin Detoxification." Journal of Agricultural and Food Chemistry 15(4): 679-&. ://WOS:A19679651300025

Trager, W. T., A. D. Campbell, et al. (1964). "Comparison of Assay Procedures for Aflatoxin in Peanut Products." Journal of the Association of Official Agricultural Chemists 47(6): 993-&. ://WOS:A19642888B00024

Trucksess, M. W., J. L. Richard, et al. (1983). "Absorption and Distribution Patterns of Aflatoxicol and Aflatoxins-B1 and Aflatoxin-M1 in Blood and Milk of Cows Given Aflatoxin-B1." American Journal of Veterinary Research 44(9): 1753-1756. ://WOS:A1983RF01200030

Trucksess, M. W. and P. M. Scott (2008). "Mycotoxins in botanicals and dried fruits: A review." Food Additives and Contaminants 25: 181-192. ://WOS:000253659900007 Botanicals are used in many countries for medicinal and general health-promoting purposes. Numerous natural occurrences of mycotoxins in botanicals and dried fruits have been reported. Aflatoxins or ochratoxin A (OTA) have been found in botanicals such as ginseng, ginger, liquorice, turmeric, and kava-kava in the USA, Spain, Argentina, India, and some other countries, while fumonisins have been found in medicinal wild plants in South Africa and in herbal tea and medicinal plants in Turkey. Zearalenone was identified in ginseng root. Dried fruits can be contaminated with aflatoxins, OTA, kojic acid, and, occasionally, with patulin or zearalenone. One main area of concern is aflatoxins in dried figs; bright greenish yellow fluorescence under ultraviolet light is associated with aflatoxin contamination. OTA in dried vine fruits (raisins, sultanas, and currants) is another concern. There are also reports of aflatoxins in raisins and OTA in dried figs, apricots, dried plums (prunes), dates, and quince. Maximum permitted levels in the European Union include 4 mu g kg(-1) for total aflatoxins in dried fruit intended for direct consumption and 10 mu g kg(-1) for OTA in dried vine fruit. This review discusses the occurrence of mycotoxins in botanicals and dried fruits and analytical issues such as sampling, sample preparation, and methods for analysis. Fungal contamination of these products, the influence of sorting, storage, and processing, and prevention are also considered.

Trucksess, M. W. and L. Stoloff (1979). "Extraction, Cleanup, and Quantitative-Determination of Aflatoxins B1 and M1 in Beef-Liver." Journal of the Association of Official Analytical Chemists 62(5): 1080-1082. ://WOS:A1979HP42600022

Trucksess, M. W. and L. Stoloff (1980). "Comparison of 3 Methods for Determining Aflatoxins in Sunflower Seed Meals." Journal of the Association of Official Analytical Chemists 63(6): 1357-1358. ://WOS:A1980KR83000038

Trucksess, M. W. and L. Stoloff (1980). "Thin-Layer Chromatographic Determination of Aflatoxins in Dry Ginger Root and Ginger Oleoresin." Journal of the Association of Official Analytical Chemists 63(5): 1052-1054. ://WOS:A1980KH85100018

Trucksess, M. W., L. Stoloff, et al. (1982). "Aflatoxicol and Aflatoxin-B1 and Aflatoxin-M1 in the Tissues of Pigs Receiving Aflatoxin." Journal of the Association of Official Analytical Chemists 65(4): 884-887. ://WOS:A1982NY05700019

Trucksess, M. W., L. Stoloff, et al. (1988). "Effect of Temperature, Water Activity and Other Toxigenic Mold Species on Growth of Aspergillus- Flavus and Aflatoxin Production on Corn, Pinto Beans and Soybeans." Journal of Food Protection 51(5): 361-363. ://WOS:A1988N598300002

Trucksess, M. W., L. Stoloff, et al. (1977). "Thin-Layer Chromatographic Determination of Aflatoxin-B1 in Eggs." Journal of the Association of Official Analytical Chemists 60(4): 795-798. ://WOS:A1977DQ78900007

Trucksess, M. W., L. Stoloff, et al. (1983). "Aflatoxicol and Aflatoxin-B1 and Aflatoxin-M1 in Eggs and Tissues of Laying Hens Consuming Aflatoxin-Contaminated Feed." Poultry Science 62(11): 2176-2182. ://WOS:A1983RR59300009

Tubajika, K. M. and K. E. Damann (2001). "Sources of resistance to aflatoxin production in maize." Journal of Agricultural and Food Chemistry 49(5): 2652-2656. ://000168915200088 Drought-tolerant maize genotypes (Huffman, Z08-004, Tuxpan, PH 9, NRC 5348, Chunco, Saint Croix, and Arizona) were compared in the field and laboratory to toxin-resistant GT-MAS:gk and Yellow Creole. SDS-PAGE, scanning electron microscopy of kernel cuticle, amount of kernel wax, Aspergillus flavus kernel colonization, Aspergillus ear rot, insect damage, aflatoxin production, and their relationships were examined. SDS-PAGE showed the presence df a 14 kDa trypsin inhibitor in the kernels of all genotypes except Chunco, which contains a protein of a larger molecular weight. The 14 kDa trypsin inhibitor protein content in these genotypes was higher than in GT-MAS:gk and Yellow Creole. Scanning electron microscopy revealed that Arizona, Huffman, and Chunco genotypes had abundant wax deposits on kernel surfaces and the amount of pericarp wax was equal to or above that from GT-MAS:gk and Yellow Creole. Differences in Aspergillus ear rot ratings, fungal colonization, and insect damage by corn earworm were observed in all drought-tolerant maize genotypes as well as in the controls. Kernel screening assays showed that aflatoxin Pr levels in inoculated drought-tolerant genotypes differed significantly from those in GT-MAS:gk and Yellow Creole (LSD = 576). Aflatoxin B-1 levels in the inoculated genotypes differed significantly from those of GT-MAS:gk or Yellow Creole (LSD = 1389) when grown under drought stress conditions. Pearson correlation coefficients were significant between ear rot ratings and insect damage (r = 0.75; P = 0.01) and between Aspergillus ear rot and aflatoxin levels (r = 0.54; P = 0.05). On the basis of the parameters studied, there are indications that these genotypes were potential sources of A. flavus resistance.

Tubajika, K. M. and K. E. Damann (2002). "Glufosinate-ammonium reduces growth and aflatoxin B-1 production by Aspergillus flavus." Journal of Food Protection 65(9): 1483-1487. ://000177944700020 The herbicide glufosinate-ammonium (GA) [butanoic acid, 2- amino-4-(hydroxymethylphosphinyl)-ammonium salt] was tested at concentrations from 2 to 2,000 g GA per ml for activity against growth and aflatoxin B-1 (AFB(1)) production by the mycotoxigenic fungus Aspergillus flavus Link:Fr. The highest concentration (2,000 mug GA per ml) reduced colony diameter of A. flavus strain AF13 by 80%. AFB(1) production was inhibited by 90% at this concentration. Reduction in mycelial dry weight and AFB(1) production in response to GA application ranged from 17.2 to 97.1% and from 39.1 to 90.1%, respectively. of four concentrations tested, 2 mug GA per ml was weakly inhibitory. In the kernel screening assay, AFB(1) production was inhibited 60 to 91% when kernels were preimmersed or immersed 5 days after incubation in 200 mug GA per ml. Both concentrations (2 and 200 mug GA per ml) reduced seed germination by 25 to 50%. Results indicate that GA has an inhibitory effect on growth and AFB(1) production by A. flavus.

Tubajika, K. M., H. J. Mascagni, et al. (2000). "Susceptibility of commercial corn hybrids to aflatoxin contamination in Louisiana." Cereal Research Communications 28(4): 463-467. ://000167023600014 Susceptibility of commercial corn (Zea mays L.) hybrids to aflatoxin contamination was determined at Winnsboro, Louisiana in 1997 and 1998. Thirty-three hybrids were inoculated with 10(6) conidia/ml of Aspergillus flavus 20 days after midsilk using the pinbar technique. All corn hybrids grown in Louisiana were susceptible to A. flavus and aflatoxin contamination in the field, but differences were detected among hybrids. When averaged across 1997 and 1998, levels of aflatoxin were highest in DeKalb 683 (26,854 ng/g) and Mycogen 2725 (25,254 ng/g) and lowest in Terra TR1185 (3,967 ng/g), Terra TR1167 (5,104 ng/g), Asgrow RX 938 (5,112 ng/g), Terra TR 1226 (5,540 ng/g), Pioneer 3394 (6,354 ng/g), and Pioneer 3167 (7,174 ng/g). This study documents the extreme susceptibility of commercial corn hybrids grown in the southern United States and demonstrates the need for continued research to identify host plant resistance.

Turner, P. C., S. E. Moore, et al. (2003). "Modification of immune function through exposure to dietary aflatoxin in Gambian children." Environmental Health Perspectives 111(2): 217-220. ://000180963400036 and http://www.botanischergarten.ch/Mycotoxins/Turner-Aflatoxin-Gambian-Children.pdf Aflatoxins are immunotoxins that frequently contaminate staple foods in The Gambia and other parts of sub-Saharan Africa, resulting in high exposure throughout life. Impaired infant immune system development may be a key predictor of mortality from infectious disease. In this study we aimed to determine the effect of dietary aflatoxin exposure on a number of immune parameters in Gambian children. A cohort of 472 Gambian children 6-9 years of age was recruited. Serum aflatoxin- albumin (AF-alb) adducts were analyzed to provide a measure of exposure. Immune parameters included secretory IgA (sIgA) in saliva, cell-mediated immunity (CMI), determined using the CMI multitest where test antigens are applied to the skin, and antibody responses to both rabies and pneumococcal polysaccharide vaccines. Birth weight, current anthropometry, and micronutrient status were also recorded. AF-alb adducts were detected in 93% of the children (geometric mean level 22.3 pg/mg; range 5-456 pg/mg). AF-alb level was strongly influenced by month of sampling. In a multivariable analysis, sIgA was markedly lower in children with detectable AF- alb compared with those with nondetectable levels [50.4 mug/mg protein (95% confidence interval [CI] 48.0-52.8) and 70.2 mug/mg protein (95% Cl 61.1-79.2), respectively; p < 0.0001]. Antibody response to one of four pneumococcal serotypes, but not rabies vaccine, was weakly associated with higher levels of AF-alb. There was no association between CMI responses to test antigens and AF-alb. These data confirm that children in rural Gambia are frequently exposed to high levels of aflatoxin. The study provides evidence that sIgA in saliva may be reduced because of dietary levels of aflatoxin exposure. Given the high burden of infection- related mortality in West Africa, further investigation of the immune effects of aflatoxin exposure in children is merited.

Turner, P. C., P. Nikiema, et al. (1999). "Fumonisin contamination of food: progress in development of biomarkers to better assess human health risks." Mutation Research-Genetic Toxicology and Environmental Mutagenesis 443(1-2): 81-93. ://000081753100006 AND http://www.botanischergarten.ch/Bt/Turner-Fumonisin-Contamination-1999.pdf Fumonisins, fungal toxins produced by Fusarium monilifome, contaminate maize based foods and feeds throughout the world. They cause Liver and kidney toxicity in animals in addition to leukoencephalomalacia in horses and pulmonary edema in pigs. Fumonisin B-1 is carcinogenic in rats and mice. Ecological studies have linked consumption of fumonisin contaminated maize with oesophageal cancer in human populations in South Africa and China. This review discusses the potential health risks for people exposed to the fumonisins, and describes how mechanistic studies of toxicity in animal models have allowed the development of putative biomarkers of fumonisin exposure at the individual level. The requirements for an applicable biomarker include sample availability as well as a high specificity and sensitivity for the exposure of interest. Most environmental toxic insults involve complex exposures both to other toxins and to infections; these confounding factors need to be considered in assessing both the validity of the biomarker and the exposure-disease associations. Fumonisins can be detected in the urine of animals in feeding studies but the sensitivity of the current methodology means only highly exposed people could be monitored. Mechanistic studies indicate that ceramide synthase, an enzyme involved in sphingolipid synthesis, is one cellular target for fumonisin toxicity and carcinogenicity, and this disruption to sphingolipid metabolism increases the ratio of two sphingoid precursors, sphinganine and sphingosine. The altered ratio has been observed in tissues, serum and urine for a number of animal models suggesting it as a good candidate marker of fumonisin exposure. Despite development of analytical methods to measure this biomarker there have been no studies to date correlating it to fumonisin intake in people. Given the toxic effects of fumonisins in animals and the widespread human exposure, which has been calculated to reach 440 mu g kg(-1) body weight day(-1) in a population consuming high quantities (460 g day(-1)) of contaminated maize, then the development of biomarkers and their application in epidemiological studies should be a priority for research on these toxins. (C) 1999 Elsevier Science B.V. All rights reserved.

Udoh, J. M., K. F. Cardwell, et al. (2000). "Storage structures and aflatoxin content of maize in five agroecological zones of Nigeria." Journal of Stored Products Research 36(2): 187-201. ://000086150400010 A survey was conducted in 1994 to describe the maize storage systems, quantify the aflatoxin levels in these storage systems, and identify the main problems of maize storage recognized by both men and women farmers in five agroecological zones in Nigeria. Maize storage in bags was the most common among all farmers. The clay rhumbu was used in 4 out of 5 agroecological zones by both male and female farmers. The woven oba was found only in the southern Guinea savanna and was used predominantly by women. Only 13% of the male farmers in the southern Guinea savanna and none in the other zones stored in an improved crib while no female farmers across all the zones used the crib system of storage. Male and female farmers across all the zones identified insect infestation, and fungal and rodent attack as the main problems in their stored maize, Insect infestation was reported by 83% of the female farmers in the southern Guinea savanna zone who stored maize in bags. The highest fungal attack on stored maize was reported by 71% of the male farmers who stored maize in bags in the humid forest zone, while 75% of the male farmers who stored in bags in the Sudan savanna zone complained of rodent attack. Across all zones, farmers of both genders identified insects as the most common storage problem. Farmers who reported insect problems were significantly more likely to have aflatoxin in their stores, The highest zonal mean aflatoxin level of 125.6 mu g/kg was obtained from maize samples provided by male farmers in the Sudan savanna zone who stored maize in bags or in a rhumbu. Across the storage systems, 33% were contaminated with detectable levels of aflatoxin. No aflatoxin was detected in the storage systems of male or female farmers in the northern Guinea savanna zone in 1994. (C) 2000 Elsevier Science Ltd. All rights reserved.

Valenta, H., S. Daenicke, et al. (2001). "Comparative studies on concentration of the Fusarium mycotoxins deoxynivalenol and zearalenone in kernels of transgenic Bt maize hybrids and non transgenic hybrids. ." Proc. Nutr. Soc. Physiol. 10: 164.

van der Westhuizen, L., N. L. Brown, et al. (1999). "Sphinganine/sphingosine ratio in plasma and urine as a possible biomarker for fumonisin exposure in humans in rural areas of Africa." Food and Chemical Toxicology 37(12): 1153-1158. ://000084787800004 This study was conducted in the Transkei region of the Eastern Cape and KwaZulu-Natal province, South Africa and in the Bomet district, western Kenya. The sphinganine (Sa)/sphingosine (So) ratios in the plasma and urine of male and female volunteers consuming a staple diet of homegrown maize in Transkei, were 0.34 +/- 0.36 (mean +/- standard deviation) (n = 154) and 0.4 +/- 0.72 (n = 153), respectively and in plasma samples from KwaZulu-Natal it was 0.44 +/- 0.23 (n = 26). In Kenya, the ratios in plasma and urine were 0.28 +/- 0.07 (n = 29) and 0.34 +/- 0.20 (n = 27), respectively. Mean total fumonisin level in home-grown maize, randomly collected in Transkei from the same region where the human volunteers lived, was 580 ng/g (n = 40), as compared to the KwaZulu- Natal province, where no fumonisin (n = 17) were detected (<10 ng/g) in the home-grown maize. In Kenya, only one of seven samples was contaminated with 60 ng/g fumonisins. No significant differences were found in the Sa/So ratios between males and females within the regions nor between the different regions (P > 0.05). It is possible that the ratio is not sensitive enough to act as a biomarker for fumonisin exposure in humans at these levels of contamination in maize. This is the first report on Sa/So ratios determined in rural populations in Africa consuming home-grown maize as their staple diet. (C) 2000 Elsevier Science Ltd. All rights reserved. van der Westhuizen, L., W. C. A. Gelderblom, et al. (2004). "Disruption of sphingolipid biosynthesis in hepatocyte nodules: selective proliferative stimulus induced by fumonisin B-1." Toxicology 200(1): 69-75. ://000221821600007 In order to investigate the role of sphingolipid disruption in the cancer promoting potential of fumonisin B-1 (FB1) in the development of hepatocyte nodules, male Fischer 344 rats were subjected to cancer initiation (FB1 containing diet or diethylnitrosamine (DEN) by i.p. injection) and promotion (2- acetylaminofluorene with partial hepatectomy, 2-AAF/PH) treatments followed by a secondary FB1 dietary regimen. Sphinganine (Sa) and sphingosine (So) levels were measured by high performance liquid chromatography in control, surrounding and nodular liver tissues of the rats. The disruption of sphingolipid biosynthesis by the secondary FBI treatment in the control rats was significantly (P < 0.05) enhanced by the 2- AAF/PH cancer promotion treatment. The nodular and surrounding Sa levels returned to baseline following FBI initiation and 2- AAF/PH promotion. When comparing the groups subjected to the secondary FBI treatment, the initiation effected by FB1 was less (P < 0.01) sensitive to the accumulation of Sa in the nodular and surrounding tissues than DEN initiation and the 2- AAF/PH control treatment. In contrast, the So level of FB1 initiation was marginally increased in the nodules compared to the surrounding liver after 2-AAF/PH promotion and significantly (P < 0.05) higher with the secondary FB1 treatment. Although, the FB1-induced hepatocyte nodules were not resistant to the disruption of sphingolipid biosynthesis, the nodular So levels were increased and might provide a selective growth stimulus possibly induced by bio-active sphingoid intermediates such as sphingosine 1-phosphate (S1P). (C) 2004 Elsevier Ireland Ltd. All rights reserved. van der Westhuizen, L., G. S. Shephard, et al. (2003). "Fumonisin contamination and Fusarium incidence in corn from Santa Catarina, Brazil." Journal of Agricultural and Food Chemistry 51(18): 5574-5578. ://000184941500061 In Brazil, the southern region has the highest incidence of esophageal cancer and also the highest production and consumption of corn (Zea mays) products. Corn samples intended for human consumption from the western, northern, and southern regions of the state of Santa Catarina, southern Brazil, had mean total fumonisin B (B-1, B-2, and B-3) levels of 3.2, 3.4, and 1.7 mg/kg, respectively. Fusarium verticiffloides, the predominant fungus in the corn samples, had mean incidences (percent of kernels infected) of 14, 11, and 18% for the three regions, respectively. Additional corn samples intended for animal feed from the southern region had a mean total fumonisin level of 1.5 mg/kg and a mean F. verticiffloides incidence of 10%. The fumonisin levels in corn from the state of Santa Catarina, Brazil, were similar to the high levels determined in other high esophageal cancer incidence regions of the world. van der Westhuizen, L., G. S. Shephard, et al. (1998). "Inhibition of sphingolipid biosynthesis in rat primary hepatocyte cultures by Fumonisin, B-1 and other structurally related compounds." Food and Chemical Toxicology 36(6): 497-503. ://000074534900005 The fumonisins and toxins produced by Alternaria alternata f. sp. lycopersici (AAL toxins) are structurally related mycotoxins that disrupt sphingolipid biosynthesis by inhibiting the rate-limiting enzyme, ceramide synthase. Rat primary hepatocytes were exposed to fumonisin B-1 (FB1), its N-acetyl analogue, FA(1), its fully hydrolysed analogue, AP(1) and the AAL toxins (TA and TB) at concentrations of 1 mu M for 40 hr in culture. The extent to which these compounds disrupt sphingolipid biosynthesis in hepatocytes in vitro was investigated by analysing the sphingosine (So) and sphinganine (Sa) levels by HPLC. The inhibition of ceramide synthase was irreversible as the Sa:So ratio was maximally increased by FB1 after 24 hr of exposure and the subsequent removal of FB1 had no effect on the ratio as compared with the 40-hr incubation period in the presence of FB1. The Sa concentration was significantly (P < 0.01) increased in all the cultures treated with the different structurally related compounds, while only AP(1) increased the So concentration significantly (P < 0.05) above the control. As AP(1) was found to be less effective in disrupting sphingolipid biosynthesis it would appear that the tricarballylic (TCA) moiety is required for maximal inhibition of ceramide synthase. The presence of an amino group appears not to be a requisite for activity, since FA(1) increased the Sa:So ratio to the same extent as FBI. The AAL toxins TA and TB increased the Sa concentration significantly (P < 0.01) above that of FBI and FA(1), while the Sa:So ratios were altered to the same extent. The structural requirements for the induction of cytotoxicity differ from those required for ceramide synthase inhibition as TA and TB were significantly (P < 0.05 to P < 0.01) less toxic to primary hepatocytes than FBI at all the concentrations tested. (C) 1998 Elsevier Science Ltd. All rights reserved.

Vanegmond, H. P. (1995). "Mycotoxins - Regulations, Quality Assurance and Reference Materials." Food Additives and Contaminants 12(3): 321-330. ://A1995RC65700004

Vanwalbe.W, P. M. Scott, et al. (1968). "Mycotoxins from Food-Borne Fungi." Canadian Journal of Microbiology 14(2): 131-&. ://WOS:A1968A822000007

Vanwalbeek, M., P. M. Scott, et al. (1967). "Studies on Mycotoxins and Mycotoxic Fungi from Foods." Canadian Journal of Public Health 58(1): 31-31. ://WOS:A1967ZN33300028

Vasanthi, S. and R. V. Bhat (1998). "Mycotoxins in foods - Occurrence, health & economic significance & food control measures." Indian Journal of Medical Research 108: 212-224. ://000077579000006

Velluti, A., S. Marin, et al. (2001). "Fumonisin B-1, zearalenone and deoxynivalenol production by Fusarium moniliforme, F proliferatum and F graminearum in mixed cultures on irradiated maize kernels." Journal of the Science of Food and Agriculture 81(1): 88-94. ://000166561000015 The impact on fungal growth and mycotoxin formation of interactions between fumonisin-producing isolates of Fusarium moniliforme and F proliferatum and a zearalenone (ZEA)- and deoxynivdenol (DON)-producing isolate of F graminearum inoculated together on irradiated maize at 15 and 25 degreesC and at 0.98, 0.95 and 0.93 a(w) was studied. The presence of F graminearum decreased the fungal populations (CFUg(-1) grain) of F moniliforme and F proliferatum under almost all conditions tested. In the presence of F moniliforme, CFUs of F graminearum increased significantly at 25 OC, especially at 0.93 and 0.95 a(w), while the presence of F proliferatum caused them to increase at 15 degreesC. The presence of F graminearum always inhibited FB, production, except at 25 degreesC and 0.98a(w) where it increased. However, the observed differences were not statistically significant. There was no effect of fungal interaction on ZEA production by F graminearum; however, when paired with F moniliforme and Ii proliferatum, DON production by F graminearum was significantly stimulated, especially at 0.98a(w). (C) 2000 Society of Chemical Industry.

Velluti, A., V. Sanchis, et al. (2003). "Inhibitory effect of cinnamon, clove, lemongrass, oregano and palmarose essential oils on growth and fumonisin B-1 production by Fusarium proliferatum in maize grain." International Journal of Food Microbiology 89(2-3): 145-154. ://000187443400004 The effect of cinnamon, clove, oregano, palmarose and lemongrass oils on growth and FBI production by three different isolates of F. proliferatum in irradiated maize grain at 0.995 and 0.950 a(w) and at 20 and 30 degreesC was evaluated. The five essential oils inhibited growth of F. proliferatum isolates at 0.995 a(w) at both temperatures, while at 0.950 a(w) only cinnamon, clove and oregano oils were effective in inhibiting growth of F. proliferatum at 20 degreesC and none of them at 30 degreesC. Cinnamon, oregano and palmarose oils had significant inhibitory effect on FB1 production by the three strains of F. proliferatum at 0.995 a(w) and both temperatures, while clove and lemongrass oils had only significant inhibitory effect at 30 degreesC. No differences were found using 500 or 1000 mug essential oil g(-1). At 0.950 a(w), none of the essential oils had any significant effect on FBI production. The results suggest that mainly cinnamon and oregano oils could be effective in controlling growth and FBI production by F. proliferatum in maize under preharvest conditions. (C) 2003 Elsevier Science B.V. All rights reserved.

Vergopoulou, S., D. Galanopoulou, et al. (2001). "Methyl jasmonate stimulates aflatoxin B-1 biosynthesis by Aspergillus parasiticus." Journal of Agricultural and Food Chemistry 49(7): 3494-3498. ://000170043400057 Aflatoxin B-1 (AFB(1)) is a highly toxic and carcinogenic metabolite produced by certain Aspergillus species on agricultural commodities. One factor promoting the production of aflatoxin is the presence of high levels of fatty acid hydroperoxides often found in plant material under stress. Jasmonic acid (JA) and its methyl ester (MeJA) are derived from linolenic acid, and their biosyntheses involve the production of lipid hydroperoxides. Exposure of aflatoxigenic mold to jasmonates is likely because the mold attacks plant material and possibly initiates the production of jasmonates. In this study the effect of MeJA on the growth of Aspergillus parasiticus and AFB(1) biosynthesis is reported. MeJA, at a final concentration of 10(-4) M in yeast extract sucrose medium, did not have any apparent effect on mycelial growth during the 16 days of observation but did increase significantly the levels of AFB(1) after the seventh day of growth. After the ninth day, AFB(1) production was decreased in contrast to the control cultures, where the production was constantly increasing. AFB(1) determination was performed by immunoaffinity and HPLC after derivatization to AFB(2a).

Visconti, A., A. Boenke, et al. (1996). "European intercomparison study for the determination of the fumonisins content in two maize materials." Food Additives and Contaminants 13(8): 909-927. ://A1996VU46100005

Visconti, A. and M. B. Doko (1994). "Survey of Fumonisin Production by Fusarium Isolated from Cereals in Europe." Journal of Aoac International 77(2): 546-550. ://A1994NF07800041

Visconti, A., M. B. Doko, et al. (1994). "Stability of Fumonisins (Fb(1) and Fb(2)) in Solution." Food Additives and Contaminants 11(4): 427-431. ://A1994PA73700002

Visconti, A., M. B. Doko, et al. (1996). "European intercomparison study for the determination of fumonisins in maize." Mikrochimica Acta 123(1-4): 55-61. ://A1996UR89200008

Visconti, A., M. Solfrizzo, et al. (1996). "Stability of fumonisins at different storage periods and temperatures in gamma-irradiated maize." Food Additives and Contaminants 13(8): 929-938. ://A1996VU46100006

Voss, K. A., P. C. Howard, et al. (2002). "Carcinogenicity and mechanism of action of fumonisin B1: a mycotoxin produced by Fusarium moniliforme (= F. verticillioides)." Cancer Detection and Prevention 26(1): 1-9. http://www.sciencedirect.com/science/article/B6X28-45MCS85-2/2/936b0b4af0c1ddfa52f8764bf7d22082 AND http://www.botanischergarten.ch/Bt/Voss-Carcinogenicity-FumonisinB1-2002.pdf Abstract Fumonisins are fungal metabolites and suspected human carcinogens. They inhibit ceramide synthase in vitro, enhance tumor necrosis factor α (TNFα) production, and cause apoptosis. Fumonisin B1 (FB1) was fed to rats and mice for 2 years or, in separate studies, given to rats or mice for up to 4 weeks. Kidney tubule adenomas and carcinomas were found in male rats fed ≥50 ppm, whereas liver adenomas and carcinomas were found in female mice fed ≥50 ppm for 2 years. In the short-term studies, increases in tissue concentration of the ceramide synthase substrate sphinganine (Sa) and the Sa to sphingosine (So) ratio were correlated with apoptosis. Further, hepatotoxicity was ameliorated in mice lacking either the TNFR1 or the TNFR2 TNFα receptors. Thus, FB1 was carcinogenic to rodents and the findings support the hypothesis that disrupted sphingolipid metabolism and TNFα play important roles in its mode of action.

Voss, K. A., R. T. Riley, et al. (2001). "An overview of rodent toxicities: Liver and kidney effects of fumonisins and Fusarium moniliforme." Environmental Health Perspectives 109(2 supplement): 259-266. ://WOS:000168824500012 AND http://www.botanischergarten.ch/Bt/Voss-Overview-Rodent-Fumonisin-2001.pdf Fumonisins are produced by Fusarium moniliforme (= F. verticillioides) and other Fusarium that grow on corn worldwide. They cause fatal toxicoses of horses and swine. Their effects in humans are unclear, but epidemiologic evidence suggests that consumption of fumonisin-contaminated corn contributes to human esophageal cancer in southern Africa and China. Much has been learned from rodent studies about fumonisin B-1 (FB1), the most common homologue. FB, is pearly absorbed and rapidly eliminated in feces. Minor amounts are retained in liver and kidneys. Unlike other mycotoxins, fumonisins cause the same liver cancer promotion and subchronic (studies less than or equal to 90 days) liver and kidney effects as F. moniliforme. FB1 induces apoptosis of hepatocytes and of proximal tubule epithelial cells. More advanced lesions in both organs are characterized by simultaneous cell loss (apoptosis and necrosis) and proliferation (mitosis). Microscopic and other findings suggest that an imbalance between cell loss and replacement develops, a condition favorable for carcinogenesis. On the molecular level, fumonisins inhibit ceramide synthase, and disrupt sphingolipid metabolism and, theoretically, sphingolipid-mediated regulatory processes that influence apoptosis and mitosis. Liver sphingolipid effects and toxicity are correlated, and ceramide synthase inhibition occurs in liver and kidney at doses below their respective no-observed-effect levels. FB1 does not cross the placenta and is not teratogenic in vivo in rats, mice, or rabbits, but is embryotoxic at high, maternally toxic doses. These data have contributed to preliminary risk evaluation and to protocol development for carcinogenicity and chronic toxicity studies of FB1 in rats and mice.

Vurro, M. and B. E. Ellis (1997). "Effect of fungal toxins on induction of phenylalanine ammonia- lyase activity in elicited cultures of hybrid poplar." Plant Science 126(1): 29-38. ://A1997XK28400004 Eleven fungal phytotoxins were tested for their ability to selectively interfere with elicitor-induced increases in phenylalanine ammonia-lyase (PAL) activity in hybrid poplar suspension cultures. The toxins varied greatly in their impact on cell growth, oxygen consumption and PAL induction. At a concentration of 10(-4) M, cytochalasin A and zearalenone severely depressed values for all three parameters, while fusaric acid, cytochalasin B, fumonisin B, and fusarenone X were somewhat less inhibitory. Fumonisin B, displayed selectivity in that it strongly inhibited growth and respiration, while having no effect on PAL induction. By contrast, pinolidoxin and putaminoxin were also selective, since at 10(-4) M they had little effect on cell growth but were able to suppress PAL induction by 40-50%. Selective suppression of PAL induction was also revealed when lower concentrations of fusarenone X were assayed. These results suggest that, in addition to their cytotoxic effects, some phytotoxins could directly suppress specific defence responses in plant cells during pathogenesis. (C) 1997 Elsevier Science Ireland Ltd.

Walker, R. D. and D. G. White (2001). "Inheritance of resistance to aspergillus ear rot and aflatoxin production of corn from CI2." Plant Disease 85(3): 322-327. ://000167258200016 This study determined the types and magnitude of gene action, estimated heritabilities, and predicted gain from selection for resistance to Aspergillus ear rot and aflatoxin production in the cross of resistant corn inbred CI2 to susceptible inbred B73 in 1998 and 1999. The warm, dry summer of 1998 favored aflatoxin production, whereas the conditions of 1999 did not. Resistance to ear rot was mainly controlled by additive gene action. Aflatoxin values were analyzed by individual years (environments) because of the highly significant generation x environment interaction. Resistance to aflatoxin production was mainly controlled by epistasis in 1998 and by additive gene action in 1999. Heritabilities for ear rot and aflatoxin production were higher in the F-3 generation than in the BCP1- selfed generation. In 1998, Spearman's correlation coefficients between Aspergillus ear rot ratings and aflatoxin values for the F-3 and the BCP1-selfed families were not significant (P > 0.05). In 1999, both were highly significant (P < 0.01), but low at 0.41 and 0.17 for the F-3 and BCP1-selfed generations, respectively. We found that CI2 is not an acceptable source of resistance due to lower heritabilities and disease resistance compared to other sources of resistance.

Wallin, J. R., N. W. Widstrom, et al. (1991). "Maize Populations with Resistance to Field Contamination by Aflatoxin-B1." Journal of the Science of Food and Agriculture 54(2): 235-238. ://A1991FA04000008 Maize (Zea mays L) germplasm is needed with resistance to infection by Aspergillus flavus and/or subsequent contamination by aflatoxin B1 (AFB1). A select group of maize populations were evaluated for their resistance to AFB1 contamination at three locations. Four populations (Ibadan B and three others derived from crosses between Corn Belt inbreds and diploid perennial teosinte, Zea diploperennis) were compared with a susceptible hybrid check in a randomised complete block experiment with 10 replicates in Georgia, Missouri and South Carolina for two years. Ears were not inoculated, and naturally occurring concentrations of AFB1 in harvested grain were analysed for population differences. Ibadan B and Mo20W x Z diploperennis had significantly lower average amounts of AFB1, 19-mu-g kg-1 and 18-mu-g kg-1, respectively, than other test entries. Backcrossing to susceptible Corn Belt inbreds produced populations as susceptible as the check when resistance was measured as the concentrations of AFB1 in the grain. The consistency and significance of low AFB1 concentrations for Ibadan B and Mo20W x Z diploperennis suggest that these may be useful sources of resistance.

Wang, E., W. P. Norred, et al. (1991). "Inhibition of Sphingolipid Biosynthesis by Fumonisins - Implications for Diseases Associated with Fusarium-Moniliforme." Journal of Biological Chemistry 266(22): 14486-14490. ://WOS:A1991FZ35100060 AND http://www.botanischergarten.ch/Bt/Wang-Inhibition-Sphingolipid-1991.pdf

Wang, E., P. F. Ross, et al. (1992). "Increases in Serum Sphingosine and Sphinganine and Decreases in Complex Sphingolipids in Ponies Given Feed Containing Fumonisins, Mycotoxins Produced by Fusarium-Moniliforme." Journal of Nutrition 122(8): 1706-1716. ://WOS:A1992JE88300014 AND http://www.botanischergarten.ch/Bt/Wang-Increases-Sphingosine-1992.pdf Consumption of food contaminated with Fusarium moniliforme causes leucoencephalomalacia and hepatotoxicity in horses, pulmonary edema in pigs and liver cancer in rats, and has been correlated with esophageal cancer in humans. The causative agents are thought to be a family of compounds called fumonisins, which have recently been shown to be potent inhibitors of sphingosine (sphinganine) N-acyltransferase. Because inhibition at this step blocks the formation of complex sphingolipids while leading to accumulation of sphinganine, we hypothesized that exposure of animals to fumonisin-contaminated feed might be detected by analyses of serum sphingolipids. Within days of giving ponies feed contaminated with 15 to 44-mu-g/g fumonisin B1, there was an increase in the amount of free sphinganine (and sometimes sphingosine) and a reduction in complex sphingolipids. Free sphinganine and sphingosine decreased when ponies consumed less of the contaminated feed, and increased again when they consumed more fumonisin. When toxicosis was evident as indicated by other serum markers, complex sphingolipids as well as free sphingosine and sphinganine were elevated, probably due to loss of sphingolipids from dying cells. These findings establish that consumption of fumonisin-contaminated feed disrupts sphingolipid metabolism. Because the changes in sphinganine and sphingosine were seen before liver enzymes were noticeably elevated, they may be an early marker of exposure to fumonisins.

Watson, A. J., L. J. Fuller, et al. (1999). "Homologs of Aflatoxin Biosynthesis Genes and Sequence of aflR in Aspergillus oryzae and Aspergillus sojae." Appl. Environ. Microbiol. 65(1): 307-310. http://aem.asm.org/cgi/content/abstract/65/1/307 and http://www.botanischergarten.ch/Mycotoxins/Watson-Homologs-Aflatox-1999.pdf The presence, but not expression, of homologs of three structural genes and a regulatory gene necessary for aflatoxin biosynthesis in Aspergillus parasiticus and A. flavus was shown for A. oryzae and A. sojae. Homologs of the regulatory gene aflR were cloned and sequenced from A. oryzae and A. sojae.

Wehner, F. C., W. F. O. Marasas, et al. (1978). "Lack of Mutagenicity to Salmonella-Typhimurium of Some Fusarium Mycotoxins." Applied and Environmental Microbiology 35(4): 659-662. ://A1978EV71400006

Wenehed, V., A. Solyakov, et al. (2003). "Cytotoxic response of Aspergillus fumigatus-produced mycotoxins on growth medium, maize and commercial animal feed substrates." Food and Chemical Toxicology 41(3): 395-403. ://000180609800009 The occurrence of mycotoxin-producing moulds in animal feed is a severe problem since the quality of the feed is reduced and thereby both animal and human health can be affected. Aspergillus fumigatus is a common fungus found in improperly stored animal feed and the abundance of spores of the fungus is frequently spread into the air, exposing individuals who stay in areas where the fungus develops. The cytotoxic activities of extracts from three different A. fumigatus-inoculated substrates: (i) CzDox- broth; (ii) maize; and (iii) commercial feed grain as well as from gliotoxin, a mycotoxin produced by A. fumigatus, were studied in vitro using human neuroblastoma (SH-SY5Y) cells. Extracts of cultures from the gliotoxin- producing strain of A. fumigatus possessed cytotoxic activity in the cell system. Pure gliotoxin caused a 20% reduction of total protein content (EC20) at 0.12 +/- 0.02 muM, but also a 20% reduction in the number of neurites per cell body as compared with control cells (ND20) at 0.06 +/- 0.01 muM. The results show that use-of the SH-SY5Y cell model is a promising approach for detecting toxic activity in animal feed. Furthermore, the neurite degeneration of gliotoxin has to be investigated for estimation of a potentially neurotoxic risk. (C) 2002 Elsevier Science Ltd. All rights reserved.

Werner, D., W. Gelderblom, et al. (2002). "The effect of dietary iron overload on the toxicological of fumonisin Bi in mice Fischer rats." Hepatology 36(4): 2107. ://000178301702089

Wessel, J. R. and L. Stoloff (1973). "Regulatory Surveillance for Aflatoxin and Other Mycotoxins in Feeds, Meat, and Milk." Journal of the American Veterinary Medical Association 163(11): 1284-1287. ://WOS:A1973R452000017

Wheeler, M. H. and D. Bhatnagar (1995). "Inhibition of Aflatoxin Production by Aspergillus-Flavus with Pentachlorobenzyl Alcohol, Phthalide, and Pyroquilon." Pesticide Biochemistry and Physiology 52(2): 109-115. ://A1995RF14700004 Two isolates of Aspergillus flavus were grown in shake cultures for 4 days at 30 degrees C with 0 to 8 mu g/ml of 2,3,4,5,6- pentachlorobenzyl alcohol (PCBA) or phthalide and 0 to 30 mu g/ml of pyroquilon. The three compounds significantly inhibited the accumulation of aflatoxins B-1, B-2, and B-2a in cultures of both isolates. The effect of PCBA was most pronounced, followed by phthalide and then pyroquilon. With isolate SRRC- 2089, the control contained 365 +/- 45 mu g of aflatoxin B-1 per gram mycelial dry weight, while in cultures treated with 8 mu g/ml PCBA, phthalide or pyroquilon, aflatoxin B-1 levels decreased by 98, 86, and 48%, respectively. At the 8 mu g/ml level, phthalide and pyroquilon did not significantly inhibit fungal growth with SRRC-2089, but PCBA caused a decrease of 12% in mycelial dry weight. Precursor feeding studies with [C- 14]norsolorinic acid demonstrated that the enzymes converting norsolorinic acid and later precursors to aflatoxins were not inhibited by these compounds. Thus, inhibition of aflatoxin synthesis by PCBA, phthalide, and pyroquilon seems to be earlier in the biosynthetic pathway before the synthesis of norsolorinic acid. (C) 1995 Academic Press, Inc.

Wheeler, M. H., D. Bhatnagar, et al. (1991). "Effects of Chlobenthiazone on Aflatoxin Biosynthesis in Aspergillus-Parasiticus and Aspergillus- Flavus." Pesticide Biochemistry and Physiology 41(2): 190-197. ://A1991GM05100009

Wheeler, M. H., D. Bhatnagar, et al. (1989). "Chlobenthiazone and Tricyclazole Inhibition of Aflatoxin Biosynthesis by Aspergillus-Flavus." Pesticide Biochemistry and Physiology 35(3): 315-323. ://A1989CA72300012

Whitaker, T. B., M. W. Trucksess, et al. (2004). "Evaluation of sampling plans to detect Cry9C protein in corn flour and meal." Journal of Aoac International 87(4): 950-960. ://000222479200021 StarLink is a genetically modified corn that produces an insecticidal protein, Cry9C. Studies were conducted to determine the variability and Cry9C distribution among sample test results when Cry9C protein was estimated in a bulk lot of corn flour and meal. Emphasis was placed on measuring sampling and analytical variances associated with each step of the test procedure used to measure Cry9C in corn flour and meal. Two commercially available enzyme-linked immunosorbent assay kits were used: one for the determination of Cry9C protein concentration and the other for % StarLink seed. The sampling and analytical variances associated with each step of the Cry9C test procedures were determined for flour and meal. Variances were found to be functions of Cry9C concentration, and regression equations were developed to describe the relationships. Because of the larger particle size sampling variability associated with cornmeal was about double that for corn flour. For cornmeal, the sampling variance accounted for 92.6% of the total testing variability. The observed sampling and analytical distributions were compared with the Normal distribution. In almost all comparisons, the null hypothesis that the Cry9C protein values were sampled from a Normal distribution could not be rejected at 95% confidence limits. The Normal distribution and the variance estimates were used to evaluate the performance of several Cry9C protein sampling plans for corn flour and meal. Operating characteristic curves were developed and used to demonstrate the effect of increasing sample size on reducing false positives (seller's risk) and false negatives (buyer's risk).

Wiatrak, P. J., D. L. Wright, et al. (2005). "Influence of planting date on aflatoxin accumulation in Bt, non-Bt, and tropical non-Bt hybrids." Agronomy Journal 97(2): 440-445. ://000228037700012 AND http://www.botanischergarten.ch/Bt/Wiatrak-Aflatoxin-2005.pdf Aflatoxin, produced by the fungus Aspergillusflavus Link, reduces the value of corn (Zea mays L.) and is usually associated with high temperatures, water stress, and insect damage. The objective of this study was to determine if Bt (Bacillus thuringiensis) corn hybrids or "tropical" germplasm could reduce aflatoxin accumulation with later planting dates. Aflatoxin accumulation (B-1, B-2, G(1), and G(2)) in corn grain was evaluated on Bt, non-Bt, and tropical non-Bt hybrids and four planting dates (March, April, May, and June) from 1998 to 2000. Aflatoxin concentration in corn varied across years but generally decreased with later planting date. In 1998, aflatoxin accumulation was lower in Bt (314 ng g(-1)) than non-Bt hybrids (634 ng g-1) but not different than tropical non-Bt hybrid (470 ng g-1). However, aflatoxin contamination was lower from Bt hybrids (70 ng g(-1)) than from the tropical non-Bt hybrid (259 ng g(-1)) but not different in non-Bt hybrids (86 ng g(-1)) in 1999. In 2000, aflatoxin levels were low, and hybrid had no effect on aflatoxin concentration. Temperature and irrigation effects on aflatoxin accumulation were not consistent. In-creased temperature and delayed harvest may lead to aflatoxin accumulation before harvest. However, precipitation may influence aflatoxin levels in some years. The results of this study indicate that aflatoxin accumulation in corn may be decreased with later planting date, and less accumulation in Bt than non-Bt or tropical non-Bt hybrids may be indirectly explained by insect reductions.

Wicklow, D. T. (1999). "Influence of Aspergillus flavus strains on aflatoxin and bright greenish yellow fluorescence of corn kernels." Plant Disease 83(12): 1146-1148. ://000083850100014 The objective of this study was to relate the diversity of a naturally occurring population of Aspergillus flavus to their ability to contaminate grain with aflatoxin and produce bright greenish yellow fluorescent (BGYF) kernels. A total of 19 strains of A. flavus isolated from a corn field near Kilbourne, Illinois were used as inoculum, including 16 genotypes (DNA fingerprinting), and representing both aflatoxin producers and non-producers. A commercial corn hybrid (Pioneer 3394) was grown in this field in 1996 and 1998. A total of 20 ears in the late-milk to early-dough stage of maturity were inoculated with each A. flavus strain using a toothpick-wound procedure. At harvest, 20 to 24 of the kernels nearest to each wounded site were separated into three categories: wound-inoculated kernels, intact BGYF kernels, and all other intact kernels. Sample weights of intact BGYF kernels in 1996 and 1998 grain samples averaged 5.0 and 9.5% of the total sample weight, respectively. Aflatoxin-producing strains were associated with a higher frequency (P < 0.05) of BGYF kernels for grain samples harvested in 1998. Removal of the individual wound-inoculated kernels and the intact BGYF kernels from corn ears inoculated with 13 aflatoxin-producing strains of A. flavus lowered mean aflatoxin values from 115 ng/g (range = <1 to 387 ng/g) to 2 ng/g for 1996 grain samples and from 744 ng/g (range = 20 to 1,416 ng/g) to 33 ng/g for 1998 grain samples. Results indicated substantial variation among A. flavus genotypes in their ability to produce aflatoxin in the germ and endosperm of infected BGYF kernels. The naturally occurring A. flavus population may include a majority of strains that produce no aflatoxin but exhibit BGYF and are thus aflatoxin "false positives" when corn grain is examined with an ultraviolet light at 365 nm. Intraspecific competition between aflatoxin- producing and non-producing strains would be expected to naturally suppress the severity of aflatoxin outbreaks within the Midwestern corn belt.

Widstrom, N. W., A. Butron, et al. (2003). "Control of preharvest aflatoxin contamination in maize by pyramiding QTL involved in resistance to ear-feeding insects and invasion by Aspergillus spp." European Journal of Agronomy 19(4): 563-572. ://000184564300008 Several resistance sources and resistance mechanisms to aflatoxin formation and corn earworm (Helicoverpa zea Boddie) damage to maize (Zea mays L.) have been identified. Based on this knowledge, experiments were initiated toward achievement of the following objectives: (1) to confirm earlier determinations on resistance traits of germplasm sources and to identify quantitative trait loci (QTL) associated with each of the traits, and (2) upon estimation of the degree of QTL effects on each trait, to generate a maize population, with chemical and physical resistance to Aspergillus spp. and ear- feeding insects, for inbred development. A 2-year field experiment to evaluate selected genotypes inoculated with A. flavus and infested with corn earworm revealed that significant variation exists among the genotypes for aflatoxin contamination and corn earworm damage. The protection of maize ears against aflatoxin contamination was primarily dependent on resistance to fungal infection and ear-feeding insects, and excellent husk coverage and tightness. A major QTL (p]) identified on chromosome IS had effects of 54.0, 42.1, and 28.3% on the phenotypic variability for concentrations of silk maysin, 3'-methoxymaysin + apimaysin, and chlorogenic acid, respectively. Markers/QTLs for husk phenotypic traits and total aflatoxin concentrations have been determined, but more detailed mapping of these chromosomic regions will be necessary to locate precise markers/QTLs for husk traits and aflatoxin production. Realizing the complexity of the Aspergillus- aflatoxin-maize system and the factors affecting aflatoxin contamination, we are directing our program toward marker- assisted breeding to enhance or improve general genetic resistance to ear-feeding insects and invasion by Aspergillus spp. Published by Elsevier Science B.V.

Widstrom, N. W., B. Z. Guo, et al. (2003). "Integration of crop management and genetics for control of preharvest aflatoxin contamination of corn." Journal of Toxicology-Toxin Reviews 22(2-3): 195-223. ://000185165300005 Aflatoxin contamination of corn in the field is influenced by several factors. In the southern U.S., insect populations are usually large every year. Drought caused by warmer and drier than normal weather is conducive to A. flavus infection and aflatoxin contamination of corn, Zea mays L. When loose-husked hybrids are used in the southern U.S., they accentuate insect damage and aflatoxin contamination. The development and breeding of "southern-type" hybrids is essential for control of preharvest aflatoxin contamination. Molecular biotechnology may make an impact on tackling the complexity of preharvest aflatoxin contamination of corn. Integration of crop management tactics and genetic strategies, conventional or molecular, may constrain the problem and help southern corn growers produce a quality, profitable crop.

Widstrom, N. W., W. W. McMillian, et al. (1994). "Preharvest Aflatoxin Contamination of Maize Inoculated with Aspergillus-Flavus and Fusarium-Moniliforme." Mycopathologia 128(2): 119-123. ://A1994QY29000010

Wild, C. P. and A. J. Hall (2000). "Primary prevention of hepatocellular carcinoma in developing countries." Mutation Research-Reviews in Mutation Research 462(2-3): 381-393. ://000086585200033 AND http://www.botanischergarten.ch/Bt/Wild-Primary-Prevention-Aflatoxin-2000.pdf Hepatocellular carcinoma (HCC) is the fifth most common cancer in the world with 80% of cases occurring in developing countries. The cancer is rapidly fatal in almost all cases with survival generally less than 1 year from diagnosis. The major risk factors for this cancer have been identified as chronic infection with hepatitis B (HBV) and hepatitis C (HCV) viruses and dietary exposure to aflatoxins. There is a safe and effective vaccine to prevent chronic HBV infection. Given estimates that approximately 70% of HCC in developing countries is attributable to HBV then vaccination could prevent more than 250,000 cases per year in these areas of the world. A major challenge now is to ensure the availability of vaccine in countries with endemic infection. Development of a vaccine against HCV is more problematic due to the genetic heterogeniety of the virus. However, with 24% of HCC in developing countries attributable to HCV (approximately 93,000 cases per year) a vaccine would make a major contribution to cancer prevention. Aflatoxins contaminate dietary staple foods (groundnuts, maize), are patent animal hepatocarcinogens and are carcinogenic in humans with particularly high risks in individuals with a concomitant infection with HBV. Reduction of exposure can be addressed at the community level either pre- or post-harvest by limiting fungal contamination of crops; approaches may involve low technology post-harvest measures to limit fungal growth or genetic engineering of crops to be resistant to fungal infection or toxin biosynthesis. An alternative measure is to modulate the metabolism of aflatoxins once ingested using chemopreventive agents e.g., oltipraz. The resources available in countries with endemic hepatitis infection and fungal contamination of foods are often severely Limited. Clearly HBV vaccination has to be the priority in the reducing the incidence of HCC. However, there are currently 360 million chronic HBV carriers worldwide and HBV vaccine is still not incorporated into many national immunisation programs. Thus measures to reduce food spoilage by fungi and the associated dietary exposure to aflatoxins is also a desirable public health goal. (C) 2000 Elsevier Science B.V. All rights reserved.

Wildman, J. D., L. Stoloff, et al. (1967). "Aflatoxin Production by a Potent Aspergillus Flavus Link Isolate." Biotechnology and Bioengineering 9(3): 429-&. ://WOS:A19679691000012

Williams, K. C. and B. J. Blaney (1994). "Effect of the Mycotoxins, Nivalenol and Zearalenone, in Maize Naturally Infected with Fusarium- Graminearum on the Performance of Growing and Pregnant Pigs." Australian Journal of Agricultural Research 45(6): 1265-1279. ://A1994NV04600013

Williams, W. P., P. M. Buckley, et al. (2002). "Southwestern corn borer (Lepidoptera : Crambidae) damage and aflatoxin accumulation in maize." Journal of Economic Entomology 95(5): 1049-1053. ://000178550000023 Aflatoxin, a potent carcinogen, is produced by the fungus Aspergillus flavus Link: Fr. Drought, high temperatures, and insect damage contribute to increased levels of aflatoxin contamination in corn, Zea mays L. Plant resistance is widely considered a desirable method of reducing aflatoxin contamination. Germplasm lines with aflatoxin resistance have been developed. This investigation was undertaken to determine whether crosses among these lines exhibited resistance to southwestern corn borer, Diatraea grandiosella Dyar, and to assess the effects of southwestern corn borer feeding on aflatoxin accumulation. Differences in ear damage among southwestern corn borer infested hybrids were significant. Estimates of general combining ability effects indicated that the lines Mp80:04, Mp420, and Mp488 contributed to reduced ear damage, and SC213 and T165 contributed to greater damage when used in hybrids. Mean aflatoxin levels were 254 ng/g for hybrids infested with southwestern corn borer larvae and 164 ng/g for noninfested hybrids in 2000 when environmental conditions were conducive to aflatoxin production. In contrast, the overall mean aflatoxin level for southwestern corn borer infested hybrids was only 5 ng/g in 1999 when environmental conditions did not favor aflatoxin accumulation. Crosses that included lines selected for aflatoxin resistance as parents (Mp,80:04 and Mp313E) exhibited lower levels of aflatoxin contamination both with and without southwestern corn borer infestation in 2000. Only the experimental line Mp80:04 contributed significantly to both reduced southwestern corn borer damage and reduced aflatoxin contamination.

Williams, W. P., G. L. Windham, et al. (2003). "Enhancing maize germplasm with resistance to aflatoxin contamination." Journal of Toxicology- Toxin Reviews 22(2-3): 175-193. ://000185165300004 Preharvest kernel infection by Aspergillus flavus and the subsequent accumulation of aflatoxin in maize grain are chronic problems in the southeastern United States. Aflatoxin is a natural carcinogen, and its presence markedly reduces the value of grain. Losses to aflatoxin contamination reach devastating levels some years. Development and deployment of maize hybrids with resistance to aflatoxin contamination is generally considered the most feasible method of reducing or eliminating the problem. Research to address the aflatoxin problem was initiated by USDA-ARS at Mississippi State, MS, in the late 1970s. The goals of the research were to identify and develop aflatoxin-resistant maize germplasm. First, reliable techniques for screening germplasm were developed. Then, germplasm from numerous sources was screened. The release of Mp313E in 1988 was the first release of maize germplasm with resistance to aflatoxin contamination. Two other germplasm lines, Mp420 and Mp715, were released in 1991 and 1999, respectively. Additional germplasm lines have been developed, but not yet released. Efforts are currently underway to identify other sources of resistance. When used in crosses with other lines, the aflatoxin-resistant lines markedly reduce the level of aflatoxin contamination in the resulting hybrids. Analysis of a diallel cross indicated that general combining ability was a significant source of variation in the inheritance of resistance to aflatoxin contamination. Efforts to combine resistance to aflatoxin combination and agronomic qualities using both conventional breeding methods and molecular marker assisted selection have been initiated.

Williams, W. P., G. L. Windham, et al. (2008). "Diallel analysis of aflatoxin accumulation in maize." Crop Science 48: 134-138. ://WOS:000252971400016 Aflatoxin, a toxin produced by the fungus Aspergillus flavus Link:Fries, occurs naturally in maize (Zea mays L.). It is a potent carcinogen, and its presence markedly reduces the value of grain. Host-plant resistance to A. flavus infection and subsequent aflatoxin accumulation is generally considered a desirable means of reducing losses to aflatoxin. Maize germplasm lines with resistance to aflatoxin contamination have been developed in Mississippi. Four of the aflatoxin-resistant lines and six other lines were used as parents to produce a diallel Cross. The diallel cross was evaluated for resistance to aflatoxin contamination in field trials conducted in Mississippi in 2005 and 2006. General combining ability (GCA) and specific combining ability (SCA) were highly significant sources of variation each year. Reciprocal effects were not significant in 2005 or in the combined analysis over years. In the analysis over years, GCA effects for reduced aflatoxin were highly significant for the four lines developed as sources of resistance: Mp313E, Mp494, Mp715, and Mp717. The GCA effect for reduced aflatoxin was also highly significant for Mo18W and NC408. These lines should be useful in developing maize lines and hybrids with resistance to aflatoxin contamination. Breeding methods that maximize the use of GCA should be effective in enhancing resistance to aflatoxin accumulation when using these germplasm lines.

Williams, W. P., G. L. Windham, et al. (2002). "Aflatoxin accumulation in conventional and transgenic corn hybrids infested with southwestern corn borer (Lepidoptera : Crambidae)." Journal of Agricultural and Urban Entomology 19(4): 227-236. ://000189114400005 Aflatoxin is a potent carcinogen produced by the fungus Aspergillus flavus Link:fr. Aflatoxin contamination of corn greatly diminishes its value and is a major impediment to profitable corn production in the South. Aflatoxin contamination is frequently linked with drought, high temperatures, and insect damage. The effects of southwestern corn borer, Diatraea grandiosella Dyar, damage on aflatoxin contamination were investigated. Aflatoxin contamination levels in conventional nonBt corn hybrids and transgenic Bt hybrids after inoculation with A. flavus and infestation with southwestern corn borer were compared. Aflatoxin contamination was highest when hybrids were inoculated with A. flavus using a technique that wounded the kernels. Aflatoxin contamination was significantly greater in nonBt than in Bt hybrids when ears were inoculated by spraying with an A. flavus conidial suspension and concurrently infesting with southwestern corn borer. Infesting conventional nonBt hybrids with southwestern corn borer resulted in significant leaf feeding, stalk tunneling, stunting, yield loss, and aflatoxin contamination. Losses were significantly reduced in transgenic Bt hybrids.

Williams, W. P., G. L. Windham, et al. (2006). "Aflatoxin accumulation in corn hybrids infested at different growth stages with southwestern corn borer (Lepidoptera : Crambidae)." Journal of Agricultural and Urban Entomology 23(2): 97-103. ://WOS:000248518200005 Aflatoxin is a potent toxin produced by the fungus Aspergillus flavus. Contamination of corn, Zea mays L., with aflatoxin greatly reduces the value of corn grain and is a major impediment to profitable corn production in the South. Infestation of developing corn ears with southwestern corn borer, Diatraea grandiosella Dyar (Lepidopera: Crambidae), increases the likelihood of aflatoxin contamination. In this investigation, six corn hybrids with different levels of resistance to southwestern corn borer damage and aflatoxin contamination were evaluated for damage by southwestern corn borer and aflatoxin contamination after infestation with southwestern corn borer at 7-d intervals from 35-84 d after planting and inoculation with an A. flavus conidial suspension. Transgenic (130 hybrids exhibited excellent resistance to Southwestern corn borer and less aflatoxin contamination than conventional versions of the same hybrids. A conventional hybrid with intermediate resistance to southwestern corn borer also exhibited relatively low levels of aflatoxin contamination. A conventional hybrid selected for resistance to aflatoxin contamination was heavily damaged by southwestern corn borer, but exhibited little aflatoxin contamination. Hybrids that have resistance to both southwestern corn borer and aflatoxin contamination appear to have the greatest potential for effectively reducing losses to aflatoxin in the South. Damage by southwestern corn borer to plants in both the vegetative and reproductive stages of growth can increase aflatoxin contamination in susceptible corn hybrids.

Williams, W. P., G. L. Windham, et al. (2005). "Southwestern corn borer damage and aflatoxin accumulation in conventional and transgenic corn hybrids." Field Crops Research 91(2-3): 329-336. ://000226473400018 AND http://www.botanischergarten.ch/Bt/Williams-Damage-Aflatoxin-2005.pdf Southwestern corn borer (Diatraea grandiosella Dyar) is a major pest of corn (Zea mays L.) in the southern United States. In addition to the direct yield losses caused by southwestern corn borer, larval feeding on developing ears provides a site for fungi to enter the ear. Aspergillus flavus Link: Fries infection and the subsequent accumulation of aflatoxin in corn gram are major limitations to profitable corn production in the southern United States. This investigation was conducted to determine the effectiveness of transgenic corn hybrids expressing the delta-endotoxin insecticidal (CryIAb) proteins isolated from Bacillus thuringiensis (Bt) in reducing southwestern corn borer damage and aflatoxin accumulation. Ear damage and aflatoxin accumulation were compared among 10 pairs of conventional nonBt and transgenic Bt corn hybrids following infestation with southwestern corn borer and inoculation with A. flavus using kernel-wounding and nonwounding techniques. Both non-Bt and Bt hybrids exhibited high levels of aflatoxin accumulation when inoculated with a kernel-wounding technique. When inoculated with a non-wounding technique and infested with southwestern corn borer, aflatoxin accumulation was significantly higher in nonBt than Bt hybrids. Aflatoxin accumulation was also significantly higher for nonBt hybrids inoculated with A. flavus and infested with southwestern corn borer than for hybrids that were only inoculated with A. flavus. Southwestern corn borer larval establishment was significantly higher on nonBt hybrids than on Bt hybrids. Larval survival was extremely low on the Bt hybrids. The results of this investigation indicate that these Bt hybrids should be effective in reducing aflatoxin contamination in areas where high southwestern corn borer infestations occur. The reduced levels of aflatoxin accumulation associated with Bt hybrids are likely a consequence of reduced insect damage rather than resistance to A. flavus infection or aflatoxin accumulation per se. (C) 2004 Elsevier B.V. All rights reserved.

Wilson, R. A., H. W. Gardner, et al. (2001). "Cultivar-dependent expression of a maize lipoxygenase responsive to seed infesting fungi." Molecular Plant-Microbe Interactions 14(8): 980-987. ://000169947000007 Maize kernels are highly susceptible to Aspergillus spp. infection and aflatoxin (AF) contamination. Fatty acid signaling molecules appear to mediate the plant-fungal interaction by affecting the growth, development, and AF production of the fungus. In particular, fatty acid derivatives of the plant lipoxygenase (LOX) pathway are implicated in the Aspergillus spp.-seed interaction. The 9(S)- hydroperoxide derivative of linoleic acid promotes transcription of AF genes, whereas the 13(S)-hydroperoxide derivative decreases AF gene expression and production; both are sporulation factors. Our goal was to identify LOX genes responsive to Aspergillus spp. colonization and determine their specificities, 9(S)- or 13(S)- , Screening maize LOX expressed sequence tags (ESTs) identified one clone, cssap 92, which is highly expressed in Aspergillus spp.-infected seed susceptible to AF contamination and repressed in lines with resistance to AF contamination, The accumulation of cssap 92 transcript was similar during Fusarium spp, infection. The cDNA clone has 94% identity to the previously described L2 LOX gene from maize. Product- specificity analysis of the CSSAP 92 protein shows that it preferentially adds oxygen to carbon 9 of linoleic acid. Because 9(S)-hydroperoxy linoleic acid has been implicated as an anatoxin-signaling molecule, it is possible that cssap 92 could be used as a biomarker that is indicative of AF resistance in maize lines.

Wilson, R. A. and T. Otsuki (2001). "Winners and Losers in a Fragmented System." Working Papers -- Agriculture. Land, commodity prices, markets No. 2689. 2004, from http://ideas.repec.org/p/wop/wobaac/2689.html and http://wbln0018.worldbank.org/research/workpapers.nsf/. Food safety and the trade-off between precaution and increased agricultural exports is at the forefront of policy debate. Discussions of food safety standards and their relation to trade have been prominent in many of the osition papers developed in advance of the World Trade Organization (WTO) Ministerial in Doha set for November 2001, for example. How food safety is addressed within the trading systems is of significant importance to developing countries which continue to rely on agricultural exports. This includes some of the least developed exporters of cereals, fruits, an nuts in Africa, Asia, and Western Hemisphere. Moreover, in a fragmented system of conflicting national standards – and lack of agreement on globally accepted regulation of food safety attributes -- export prospects for the least developed countries can be severely limited. This study examines the impact of adopting international food safety standards and harmonization of standards on global food trade patterns. The paper estimates the effect of aflatoxin standards in 15 importing (4 developing) countries on exports from 31 (21 developing ) countries. Aflatoxin is a natural substance which can contaminate certain grains and nuts when storage and drying facilities for these commodities are inadequate. Based on our analysis, we find that adopting a worldwide standard for aflatoxin B1 – the most potentially toxic of all aflatoxins -- based on current international guidelines is found to increase the cereal and nut trade among the countries studied by $US 6.1 billion from the 1998 levels. We further estimate that total world exports would rise by $38.8 billion if an international standard (Codex) were adopted, compared to the current divergent national standards in place.

Windham, G. L. and W. P. Williams (1998). "Aspergillus flavus infection and aflatoxin accumulation in resistant and susceptible maize hybrids." Plant Disease 82(3): 281-284. ://000072163100003

Windham, G. L. and W. P. Williams (2002). "Evaluation of corn inbreds and advanced breeding lines for resistance to aflatoxin contamination in the field." Plant Disease 86(3): 232-234. ://000173952300006 AND http://www.botanischergarten.ch/Bt/Windham-Evaluation-Corn-Inbreds-2002.pdf Eighteen corn inbred lines and advanced breeding lines were evaluated for resistance to aflatoxin contamination when artificially inoculated with Aspergillus flavus in 1998, 1999 (two tests), and 2000 at Mississippi State, MS, in field studies. The top ear of each plant was inoculated with the A. flavus isolate NRRL 3357 seven days after midsilk (50% of the plants in a plot had silks emerged) using the side-needle technique. Ears were harvested at kernel maturity approximately 63 days after midsilk and aflatoxin levels were measured using the Vicam AflaTest. Aflatoxin contamination in the inbreds was extremely high in 1998. Levels ranged from 139 to 21,090 ng/g. In 1999, aflatoxin contamination ranged from 17 to 1,070 ng/g in one test and 14 to 1,278 ng/g in another test. In 2000, aflatoxin levels ranged from 237 to 7,503 ng/g. Lines that supported lowest levels of aflatoxin contamination included Mp81:112, Mp92:673, Mp92:679, and Mp494. These lines provide potential new sources of resistance that can be used to move aflatoxin resistance into commercial corn hybrids.

Windham, G. L. and W. P. Williams (2007). "A comparison of inoculation techniques for inducing aflatoxin contamination and Aspergillus flavus kernel infection on corn hybrids in the field." Phytoparasitica 35(3): 244-252. ://WOS:000247118500005 Aspergillus flavus inoculation techniques were compared on aflatoxin-resistant and -susceptible corn hybrids for inducing aflatoxin contamination and A. flavus kernel infection. A dry carrier technique was comparable to the standard inoculation techniques (the side-needle and a spray technique) in differentiating between the resistant and the susceptible hybrids in the first year of the study. However, only hybrids inoculated with the side-needle technique had statistically different levels of aflatoxin and A. flavus kernel infection in the second year of the study. In a second study, a modified pinbar technique with inoculations near the tip or base of the ear was compared with the side-needle technique. When developing ears were inoculated near the base with the modified pinbar, adequate levels of aflatoxin were induced both years to distinguish between the resistant and susceptible corn hybrids. The modified pinbar technique has the potential of being a useful tool in evaluating corn germplasm for aflatoxin resistance.

Windham, G. L. and W. P. Williams (2007). "Effect of ear bagging systems on Aspergillus flavus kernel infection and aflatoxin contamination of corn hybrids grown in the field." Phytoparasitica 35(3): 277-281. ://WOS:000247118500009 Field studies were conducted for 4 years to determine the effect of various ear bagging systems on Aspergillus flavus kernel infection and aflatoxin production in developing ears of corn hybrids. Each year, corn hybrids were grown on a Myatt loam (low water-holding capacity) and a Leeper silty clay loam (high water-holding capacity). Corn cars were inoculated with A. flavus using the side-needle technique 7 days after midsilk (50% of the plants in the plot had silks emerged). For the first 2 years, inoculated ears were covered with either white or black paper pollination bags at approximately 14 days after inoculation. During the last 2 years, inoculated ears were covered with either a brown paper pollination bag or a clear plastic zip-lock bag. Daily maximum temperatures were increased 2 to 4 degrees C in all of the bagging systems over ambient temperatures. The bagging systems had a limited effect on aflatoxin production and A. flavus kernel infection in the Leeper silty clay loam. In the Myatt loam, ears covered with plastic bags had higher levels of aflatoxin contamination and A. flavus kernel infection compared with ears covered with paper bags.

Windham, G. L. and W. P. Williams (2007). "Systemic infection of stalks and ears of corn hybrids by Aspergillus parasiticus." Mycopathologia 164: 249-254. ://WOS:000249951900006 This study was conducted to explore systemic infection by the Aspergillus flavus group into corn ears via the stalk. An A. parasiticus mutant which produces norsolorinic (NOR) acid (a visible orange intermediate of the aflatoxin biosynthetic pathway) was used in field studies to monitor systemic infection of corn stalk and ear tissues. Corn hybrids resistant and susceptible to aflatoxin contamination were grown in the field and inoculated prior to tasseling by inserting A. parasiticus infested toothpicks into stalks between the 5th and 6th node below the lowest ear shoot. Beginning 2 weeks after inoculation, systemic infection by the NOR mutant was assessed weekly by collecting ear shank tissue and stalk tissue from the nodes between the infection sites and the developing ears. Ears were collected at the end of the growing season to determine the level of kernel infection by the NOR mutant. In two separate studies, the A. parasiticus NOR mutant was isolated from stalk tissues at all of node positions and ear shank tissue from several susceptible corn hybrid plants at the first harvest date 2 weeks after inoculation. The NOR mutant was also isolated from stalk and ear tissue of a resistant hybrid. The NOR mutant was only isolated from kernels of susceptible hybrids in 2003 and 2004. Infection rates of kernels in infected ears were very low (< 1%). In 2005, the fungus was found in only one kernel from an ear of the resistant hybrid. The NOR mutant was not isolated from stalks, ears, or kernels from control (uninoculated) plants grown in the plots with inoculated plants. Although infection levels of corn kernels were low, systemic movement of the A. parasiticus up the stalk appears to be another possible route to infection of developing corn ears.

Windham, G. L., W. P. Williams, et al. (2003). "Inoculation techniques used to quantify aflatoxin resistance in corn." Journal of Toxicology-Toxin Reviews 22(2-3): 313-325. ://000185165300009 The development of Aspergillus flavus inoculation techniques has played an important part in developing corn (Zea mays L.) germplasm resistant to aflatoxin contamination. Corn genotypes evaluated for aflatoxin resistance in field studies must be artificially inoculated due to the sporadic nature of aflatoxin contamination from year to year. A number of different inoculation techniques are used by researchers in the South and Midwest. Field inoculation techniques either wound developing kernels or leave the kernels intact. Non-wounding techniques apply A. flavus conidia to exposed silks or silks inside the husks without damaging kernels. Wounding techniques deliver A. flavus conidia onto kernels that have been mechanically damaged. Inoculation techniques utilizing ear feeding insects to vector conidia have also been used in field studies. Environmental conditions such as ambient temperature and drought stress appear to have a significant impact on artificial inoculations. Laboratory evaluation techniques have been developed to confirm aflatoxin resistance identified in corn genotypes in the field. Color mutants and transformants of Aspergillus spp. have been used in field and laboratory studies to identify resistant genotypes. More efficient, less labor intensive, and less costly inoculation techniques need to be developed to aid in the production of aflatoxin resistant corn hybrids.

Windham, G. L., W. P. Williams, et al. (1999). "Effects of the southwestern corn borer on Aspergillus flavus kernel infection and aflatoxin accumulation in maize hybrids." Plant Disease 83(6): 535-540. ://000080433500009 Field studies were conducted in 1995 to 1997 to determine the effect of the southwestern corn borer (SWCB) on Aspergillus flavus kernel infection and aflatoxin accumulation in maize hybrids. In 1995, when A. flavus conidia were applied to silks in a spray and SWCB neonate larvae in maize cob grits were placed in the leaf axil at the top ear of commercial hybrids, aflatoxin contamination and A. flavus kernel infection were highest in plants treated with both the fungus and the insect. In 1996, using the same inoculation and infestation techniques, aflatoxin levels and kernel infection were much lower than in 1995 and SWCB had no effect on aflatoxin contamination or kernel infection. In another study in 1996, the effect of SWCB on aflatoxin contamination and A. flavus kernel infection in hybrids resistant and susceptible to A. flavus was determined. The inoculation-infestation technique involved applying maize cob grits containing A. flavus conidia and SWCB larvae to silks. When SWCB was combined with A. flavus, aflatoxin levels and kernel infection were dramatically higher than in hybrids inoculated with A. flavus alone, regardless of whether the hybrids were resistant or susceptible to A. flavus. In 1997, die interaction of A. flavus and SWCB was determined on hybrids resistant and susceptible to A. flavus and on a commercial hybrid with and without the Bacillus thuringiensis (Bt) toxin. Maize cob grits were used to inoculate A. flavus and infest SWCB on the silks 7 or 21 days after midsilk (50% of the plants in a row had silks emerged). All four hybrids had the highest levels of Aspergillus spp. kernel infection and aflatoxin contamination when A. flavus and SWCB were applied at 21 days after midsilk. These studies indicate that SWCB can substantially increase aflatoxin levels when combined with A. flavus. However, inoculation and infestation techniques, placement of the fungus and the insect, and timing of inoculation and infestation are all critical in demonstrating a synergistic relationship between A. flavus and SWCB on aflatoxin contamination of maize.

Woloshuk, C. P., K. R. Foutz, et al. (1994). "Molecular Characterization of Aflr, a Regulatory Locus for Aflatoxin Biosynthesis." Applied and Environmental Microbiology 60(7): 2408-2414. ://A1994NV57200031 Aflatoxins belong to a family of decaketides that are produced as secondary metabolites by Aspergillus flavus and A. parasiticus. The aflatoxin biosynthetic pathway involves several enzymatic steps that appear to be regulated by the afl2 gene in A. flavus and the apa2 gene in A. parasiticus. Several lines of evidence indicate that these two genes are homologous. The DNA sequences of the two genes are highly similar, they both are involved in the regulation of aflatoxin biosynthesis, and apa2 can complement the afl2 mutation in A. flavus. Because of these similarities, we propose that these two genes are homologs, and because of the ability of these genes to regulate aflatoxin biosynthesis, we suggest that they be designated aflR. We report here the further characterization of aflR fi-om A. flavus and show that aflR codes for a 2,078-bp transcript with an open reading frame of 1,311 nucleotides that codes for 437 amino acids and a putative protein of 46,679 daltons. Analysis of the predicted amino acid sequence indicated that the polypeptide contains a zinc cluster motif between amino acid positions 29 and 56. This region contains the consensus sequence Cys- Xaa2-Cys-Xaa6-Cys-Xaa6-Cys-Xaa2-Cys-Xaa6-Cys. This motif has been found in several fungal transcriptional regulatory proteins. DNA hybridization of the aflR gene with genomic digests of seven polyketide-producing fungi revealed similar sequences in three other species related to A. flavus: A. parasiticus, A. oryzae, and A. sojae. Finally, we present evidence for an antisense transcript (aflRas) derived from the opposite strand of aflR, suggesting that the aflR locus involves some form of antisense regulation.

Woloshuk, C. P., G. L. Yousibova, et al. (1995). "Molecular Characterization of the Afl-1 Locus in Aspergillus- Flavus." Applied and Environmental Microbiology 61(8): 3019-3023. ://A1995RM01500033 An unusual mutation at the afl-1 locus, affecting aflatoxin biosynthesis in Aspergillus flavus 649, was investigated. The inability of strain 649 to produce aflatoxin was found to be the result of a large (greater than 60 kb) deletion that included a cluster of aflatoxin biosynthesis genes. Diploids formed by parasexual crosses between strain 649 and the aflatoxigenic strain 86 did not produce aflatoxin, indicating the dominant nature of the afl-1 mutation in strain 649. In metabolite feeding experiments, the diploids did not convert three intermediates in the aflatoxin pathway to aflatoxin. Northern (RNA blot) analysis of the diploids grown in medium conducive for aflatoxin production indicated that the aflatoxin pathway genes nor1, ver1, and omt1 were not expressed; however, there was low-level expression of the regulatory gene aflR. Pulsed-field electrophoresis gels indicated a larger (6 Mb) chromosome in strain 649 than the apparently homologous (4.9 Mb) chromosome in strain 86. The larger chromosome in strain 649 suggests that a rearrangement occurred in addition to the deletion. From these data, we propose that a traps-sensing mechanism in diploids is responsible for the dominant phenotype associated with the afl-1 locus in strain 649. Such a mechanism is known in Drosophila melanogaster but has not been described for fungi.

Wright, M. S., D. M. Greene-McDowelle, et al. (2000). "Effects of volatile aldehydes from Aspergillus-resistant varieties of corn on Aspergillus parasiticus growth and aflatoxin biosynthesis." Toxicon 38(9): 1215-1223. ://000086703200004 The fungi Aspergillus flavus and Aspergillus parasiticus produce a potent class of hepatocarcinogens known as aflatoxins. Corn- derived volatile compounds have been previously found to affect growth and aflatoxin production in A. flavus. In this study, the effects on A. parasiticus of three corn-derived volatile compounds, n-decyl aldehyde, hexanal and octanal, were measured. These three compounds were previously found to be variably expressed in five Aspergillus- resistant maize strains and three susceptible strains. In this study, A. parasiticus radial growth was restricted least by n- decyl aldehyde and most by octanal. Treatments of 100 mu l of both hexanal and octanal were found to completely inhibit radial growth of the fungus using an agar plate assay method. While the volatile compound n-decyl aldehyde had less of an effect on radial growth than the other volatiles, the n-decyl aldehyde treated colonies had a predominance of uniquely aerial hyphae. These colony structures were found to have more complex hyphae and significantly fewer conidiophores than the control and other aldehyde treatments. Furthermore, aflatoxin production by the fungus was reduced by n-decyl aldehyde and hexanal, but was stimulated by octanal. The results presented here indicate that all three volatile compounds reduce radial growth but only n-decyl aldehyde significantly inhibits aflatoxin biosynthesis in A. parasiticus. Published by Elsevier Science Ltd.

Wu, F. (2004). "Explaining public resistance to genetically modified corn: An analysis of the distribution of benefits and risks." Risk Analysis 24(3): 715-726. ://000222436300016 AND http://www.botanischergarten.ch/Riskbalance/Wu-Public-Resistance-2004.pdf Genetically modified (GM) crops have met with widespread approval among scientists and policy makers in the United States, but public approval of GM crops, both domestically and abroad, is progressing much more slowly. An underlying cause of public wariness may be that both nations and individual consumers do not perceive significant benefits to themselves from GM crops, while fearing the risks they may incur. In this study, an economic analysis is conducted to determine whether the benefits of one type of GM corn, Bt corn (genetically modified to resist damage from the ECB and Southwestern corn borer), outweigh the potential risks; and who the "winners" and "losers" are among stakeholder groups that may be affected by Bt corn. It is found that Bt corn growers, consumers, and industry all benefit from Bt corn adoption, though the purported health and environmental benefits of reducing chemical pesticide usage through Bt corn are negligible. Though the aggregated public benefit is large, the welfare gain to individual consumers is small and may not make up for perceived risks. While environmental and health risks of Bt corn are unlikely, the potential market risks-impacting both the organic corn market and total U.S. corn exports-are found to be significant, Currently, distributional analysis is not a part of regulatory decision making of Bt corn in the United States; yet it may help to explain why decision makers at both the government and individual-consumer levels have failed to embrace Bt corn and other GM crops.

Wu, F. (2004). "Mycotoxin risk assessment for the purpose of setting international regulatory standards." Environmental Science & Technology 38(15): 4049-4055. ://000223035400009 AND http://www.botanischergarten.ch/Mycotoxins/Wu-Regulation-2004.pdf The 2003 Council for Agricultural Science and Technology Mycotoxin report states that one 21st century goal is the development of uniform regulations worldwide for foodborne mycotoxin contamination. This study informs that endeavor by a risk assessment and economic analysis of two important mycotoxins: fumonisins and aflatoxins. The goals are to identify the nations that would be most heavily impacted by tighter mycotoxin regulations, examine costs and benefits as a function of regulatory stringency, and address risk-risk tradeoffs between health benefits and economic losses from compliance with those regulations. Among industrial nations, the United States would experience the heaviest economic losses from more precautionary mycotoxin standards. Environmental conditions in the developing world, however, are more conducive to mycotoxin accumulation in crops. Contrary to concerns expressed among policymakers, the less developed countries that would likely experience the greatest loss from tighter mycotoxin standards are not sub-Saharan African nations, but China and Argentina. If a fumonisin standard of 0.5 mg/kg were adopted worldwide, total export losses from fumonisins in corn may exceed $300 million annually: 3-fold higher than if the less stringent U.S. standard of 2 mg/kg were adopted. Likewise, export losses from aflatoxins in peanuts may exceed $450 million under the current EU regulatory standard of 4 mug/kg: almost 5-fold higher than if the U.S. standard of 20 mug/kg were adopted. Stricter standards are unlikely to improve health significantly. In developing nations such as China where hepatitis B and C are prevalent, tighter aflatoxin standards may increase health risks until improved control methods for aflatoxins are found, as high-quality crops may be exported instead of being consumed domestically.

Wu, F. (2006). "Mycotoxin reduction in Bt corn: Potential economic, health, and regulatory impacts." Transgenic Research 15(3): 277-289. ://000238328300002 AND http://www.botanischergarten.ch/Mycotoxins/Wu-Reduction-2006.pdf Genetically modified (GM) Bt corn, through the pest protection that it confers, has lower levels of mycotoxins: toxic and carcinogenic chemicals produced as secondary metabolites of fungi that colonize crops. In some cases, the reduction of mycotoxins afforded by Bt corn is significant enough to have an economic impact, both in terms of domestic markets and international trade. In less developed countries where certain mycotoxins are significant contaminants of food, Bt corn adoption, by virtue of its mycotoxin reduction, may even improve human and animal health. This paper describes an integrated assessment model that analyzes the economic and health impacts of two mycotoxins in corn: fumonisin and aflatoxin. It was found that excessively strict standards of these two mycotoxins could result in global trade losses in the hundreds of millions $US annually, with the US, China, and Argentina suffering the greatest losses. The paper then discusses the evidence for Bt corn's lower levels of contamination of fumonisin and aflatoxin, and estimates economic impacts in the United States. A total benefit of Bt corn's reduction of fumonisin and aflatoxin in the US was estimated at $23 million annually. Finally, the paper examines the potential policy impacts of Bt corn's mycotoxin reduction, on nations that are making a decision on whether to allow commercialization of this genetically modified crop.

Wu, F. (2007). "Bt corn and impact on mycotoxins." CAB Reviews: Perspectives in Agriculture, Veterinary Science, Nutrition and Natural Resources 2(060): 1-8. http://www.cababstractsplus.org/cabreviews AND http://www.botanischergarten.ch/Bt/Wu-Corn-Impact-CAB-2007.pdf This review summarizes the literature linking Bt corn and the reduction of the mycotoxins fumonisin, aflatoxin, deoxynivalenol (DON) and zearalenone. Mycotoxins in field corn cause hundreds of millions of dollars in economic losses annually in the USA, and substantially greater losses in other regions of the world. Most of the losses are from aflatoxin contamination, while significant but smaller losses are due to Fusarium mycotoxins, fumonisins and DON. The insecticidal proteins in genetically modified hybrid Bt corn (Zea mays spp.) reduce insect damage from certain Lepidopteran larvae, which in turn can reduce infection of the grain by mycotoxigenic fungi. Where such insect damage is a major factor in mycotoxin contamination, Bt corn can lower mycotoxin levels. Since such damage is not always the most important factor, experimental results have been mixed, especially with aflatoxin levels. Bt corn appears to have a greater impact on the Fusarium mycotoxins than on aflatoxin levels. Studies on economic impacts of Bt corn’s mycotoxin reduction are briefly summarized. The benefits in developing countries from mycotoxin reduction could be more significant, particularly in regions where unprocessed corn is a staple in the human diet.

Wu, F. (2007). "Measuring the economic impacts of Fusarium toxins in animal feeds." Animal Feed Science and Technology 137(3-4): 363-374. ://WOS:000249473500010 Economic impacts of mycotoxins in animal feed are difficult to measure, because information regarding animal illnesses and productivity losses due to chronic low-level exposures have been largely anecdotal. The current paper presents an original economic model that takes the first steps in measuring the various impacts of Fusarium toxins in animal feed. Two different categories of losses are considered: losses related to animal health, and trade losses related to grain rejection in the marketplace. Of animal health losses, both mortalities and morbidities are considered. The relevant trade losses concern impacts in both the domestic and international feed grain markets. A case study regarding fumonisin in US maize intended for animal feed is presented. It is estimated that in a normal year (without a significant Fusarium ear rot outbreak), the losses due to fumonisin in animal feed would total US$ 1- 20 million. In a year with a significant Fusarium carrot outbreak, losses would total US$ 31-46 million. The economic model presented here provides a framework by which farmers, grain handlers, and diverse policymakers may be able to analyze economic losses due to mycotoxins in feed grain. (c) 2007 Elsevier B.V. All rights reserved.

Wu, F., J. D. Miller, et al. (2004). "The economic impact of Bt corn resulting from mycotoxin reduction." Journal of Toxicology-Toxin Reviews 23(2-3): 397-424. ://000224372900011 AND http://www.botanischergarten.ch/Mycotoxins/Wu-Economic-Impact-2004.pdf The insecticidal proteins in genetically modified hybrid Bt corn (Zea mays spp.) reduce insect damage, which in turn can reduce infection of the grain by mycotoxigenic fungi. Lower levels of Fusarium mycotoxins, fumonisin, and deoxynivalenol in Bt corn could have significant market and health impacts, both in the United States and around the world. These impacts are foregone losses through market rejection, human health losses, and animal health losses. We estimate that at current planting levels, Bt corn saves farmers in the United States about $17 million annually through reduced fumonisin and deoxynivalenol damage alone. Though not extensively grown in developing countries, the benefits there in mycotoxin reduction could be even more significant, particularly in regions where corn is a staple in the human diet.

Wu, F. and G. P. Munkvold (2008). "Mycotoxins in ethanol co-products: Modeling economic impacts on the livestock industry and management strategies." Journal of Agricultural and Food Chemistry 56(11): 3900-3911. ://WOS:000256445300003 AND http://www.botanischergarten.ch/Bt/Wu-Mycotoxins-Ethanol-Co-products-2008.pdf The rapidly expanding U.S. ethanol industry is generating a growing supply of co-products, mostly in the form of dried distillers' grain and solubles (DDGS) or wet distillers' grains (WDG). In the United States, 90% of the co-products of maize-based ethanol are fed to livestock. An unintended consequence is that animals are likely to be fed higher levels of mycotoxins, which are concentrated up to three times in DDGS compared to grain. The model developed in this study estimates current losses to the swine industry from weight gain reduction due to fumonisins in added DDGS at $9 million ($2-18 million) annually. If there is complete market penetration of DDGS in swine feed with 20% DDGS inclusion in swine feed and fumonisins are not controlled, losses may increase to $147 million ($29-293 million) annually. These values represent only those losses attributable to one mycotoxin on one adverse outcome on one species. The total loss due to mycotoxins in DDGS could be significantly higher due to additive or multiplicative effects of multiple mycotoxins on animal health. If mycotoxin surveillance is implemented by ethanol producers, losses are shifted among multiple stakeholders. Solutions to this problem include methods to reduce mycotoxin contamination in both pre- and postharvest maize.

Wunch, K. G., J. W. Bennett, et al. (1992). "An Averufin-Accumulating Mutant of Aspergillus-Nidulans." Mycologia 84(6): 913-916. ://A1992KK46400013

Xu, H. X., S. Annis, et al. (2000). "Infection and colonization of peanut pods by Aspergillus parasiticus and the expression of the aflatoxin biosynthetic gene, nor-1, in infection hyphae." Physiological and Molecular Plant Pathology 56(5): 185-196. ://000087694400001 The aflatoxigenic fungi, Aspergillus flavus and A. parasiticus infect a wide variety of crops, all of which produce oil-rich seed. A histological study of the host-pathogen interaction between peanut, Arachis hyphogea, and A, parasiticus was performed in a system where peanuts remained attached to the plant and were inoculated without wounding. For infection studies, a genetically- tagged strain of A. parasiticus, G5, was engineered to harbor the beta-glucuronidase (GUS) reporter gene under control of the nor-1 promoter from the aflatoxin biosynthetic pathway. There was a similar temporal pattern of aflatoxin B1 production and appearance of GUS activity in cultures of A. parasiticus G5. This strain was used to follow infection and aflatoxin production during colonization of undamaged, drought-stressed peanuts. The fungus colonized ail tissues of the peanut pod and appeared to gain ingress through the corky layer of the pericarp. Both intra- and inter-cellular colonization were observed. Fungal colonization of the cotyledons resulted in Visible depletion of storage bodies within cells. Two morphologically distinct types of hyphae, wider hyphae and narrower hyphae, were seen throughout the pod tissues. Statistical analysis revealed that the narrower hyphae were significantly more likely to produce GUS activity than wider ones. GUS activity was found in hyphae infecting the pericarp, embryo and cotyledons indicating expression of aflatoxin biosynthetic genes in these tissues. Interestingly, GUS activity was not observed in the hyphae colonizing the testa. (C) 2000 Academic Press.

Yates, I. E., J. W. Arnold, et al. (2003). "Fusarium verticillioides induction of maize seed rot and its control." Canadian Journal of Botany-Revue Canadienne De Botanique 81(5): 422-428. ://000183913900002 Experimental evidence is lacking to demonstrate whether Fusarium verticiltioides (synonym = Fusarium mondiforme J. Sheld.; teleomorph = Gibberella fujikuroi (Sawada) Ito in Ito & K. Kimura, mating population A) functions as a causative agent or an opportunistic invader in seed (caryopsis) rot of maize (Zea mays L.). Previous researchers have isolated this fungus, along with many other microorganisms, from seed collected in the field long after rot commenced. The current investigations used an isolate of F. verticillioides transformed with a selectable marker and a reporter gene to inoculate previously disinfected maize seed. Seed rot developed, and F. verticillioides containing the introduced genes was isolated from inoculated, but not noninoculated, seed. Efficacy of Plantpro-45, an agent with an iodine-based active ingredient (a.i.), was analyzed for controlling growth of F. verticillioides from conidia and inoculated maize seed. A solution containing <10 μg a.i./mL inhibited growth of conidia suspended for <30 s. Furthermore, seed rot was controlled without diminishing seedling survival at 10 mg a.i./kg maize seed. Thus, F. verticillioides can function as the causative agent of maize seed rot and can be suppressed and (or) controlled at the postinfection stage with Plantpro- 45.

Ye, Y., Y. X. Zhou, et al. (2010). "Rapid detection of aflatoxin B-1 on membrane by dot-immunogold filtration assay." Talanta 81(3): 792-798. ://WOS:000276877500008 Immunofiltration assay for mycotoxins in which nitrocellulose membrane (NCM) was used as a support and enzyme was used as the label has been developed since the late 1980s. As colloidal gold is a good labeling substance that can accelerate antibody-antigen reaction which result can be read directly by naked eyes, the colloidal gold particles could replace the enzyme to be labeled to antibody in aflatoxin B-1 (AFB(1)) immunoassay. Dot-immunogold filtration assay (DIGFA) of AFB(1) on NCM was developed in this study. At first, the colloidal gold was synthesized and colloidal gold-monoclonal antibody (McAb) conjugates against AFB(1) were prepared at pH 7.0 of colloidal gold solution, 0.018 mg/mL of McAb. Then the colloidal gold-McAb conjugates were used to develop AFB(1) DIGFA, which detection time was only 15 min, six times less than that of ELISA. With this method to determine the standard AFB(1) solution, the results demonstrated a visual detection limit of approximately 2 ng/mL of AFB(1). which was similar to that of ELISA. This method had good specificities for AFG(1), AFG(2) and AFM(1) and a little cross-reactivity with AFB(2). 45 food samples collected from the markets were subjected to DIGFA and the results showed that one corn sample was positive and in agreement that of HPLC. It is suggested that DIGFA developed in current study has a potential use as a rapid and cost-effective screening tool for the determination of AFB(1) in foods in the field within 15 min without complicated steps. (C) 2010 Elsevier B.V. All rights reserved.

Yin, L., A. D. Campbell, et al. (1971). "Method for Detection of Aflatoxins-B1 and B2 in Toasted Cottonseed Meal." Journal of the Association of Official Analytical Chemists 54(1): 102-&. ://WOS:A1971I412400024

Yong, R. K. and M. A. Cousin (2001). "Detection of moulds producing aflatoxins in maize and peanuts by an immunoassay." International Journal of Food Microbiology 65(1-2): 27-38. ://000168062100004 An enzyme-linked immunosorbent assay (ELISA) was developed to detect moulds producing aflatoxins in maize and peanuts by an antibody produced to extracellular antigen from Aspergillus parasiticus. This antibody recognized species with phenotypic similarities to A. parasiticus, A. flavus and the domesticated species A. sojae and A. oryzae. For maize samples that were naturally contaminated with aflatoxins, low and high levels of aflatoxin corresponded with low and high ELISA readings for mould antigens, respectively. Maize and peanuts inoculated with 10(2) spores ml(-1) of A. parasiticus and incubated at 15 degreesC for 18 days or 21 degreesC for 7 days were analyzed for mould antigens and anatoxin levels. At 15 degreesC. mould antigens were detected by day 4 in maize when 0.16 ng g(-1) of anatoxin was detected by ELISA but not by thin layer chromatography (TLC). Antigens were detected in peanuts by day 4 before anatoxin was found. Likewise, at 21 degreesC, antigens were detected by day 4 in maize when less than 1 ng g(-1) of anatoxin was detected by ELISA but not by TLC, but by day 2 in peanuts when no anatoxin was detected. A. parasiticus could be detected before it could produce aflatoxins. Therefore, this ELISA shows potential as an early detection method for moulds that produce aflatoxins. (C) 2001 Elsevier Science B.V. All rights reserved.

Yoshizawa, T., A. Yamashita, et al. (1994). "Fumonisin Occurrence in Corn from High-Risk and Low-Risk Areas for Human Esophageal Cancer in China." Applied and Environmental Microbiology 60(5): 1626-1629. ://WOS:A1994NJ57700033 AND http://www.botanischergarten.ch/Bt/Yoshizawa-Fumonisin-China-1994.pdf

Yu, J., P. K. Chang, et al. (2000). "Genes encoding cytochrome P450 and monooxygenase enzymes define one end of the aflatoxin pathway gene cluster in Aspergillus parasiticus." Applied Microbiology and Biotechnology 53(5): 583-590. ://000087506200013 and http://www.botanischergarten.ch/Mycotoxins/Yu-Encoding-Aflatox-2000a.pdf The identification of overlapping cosmids resulted in the discovery of the aflatoxin biosynthetic pathway gene cluster in Aspergillus flavus and A. parasiticus. This finding led to the cloning and characterization of one regulatory and 16 structural genes involved in aflatoxin biosynthesis, including the most recent report on the gene, ordA, which has been identified to be involved in the formation of four aflatoxins (B-1, B-2, G(1) and G(2)). However, these genes do not account for all the identified chemical/biochemical steps in aflatoxin synthesis and efforts are underway to identify the genes controlling the other steps. We are also attempting to define the outer boundaries of the aflatoxin pathway gene cluster in the Aspergillus genome. For this goal, we extended sequencing in both directions from the existing (60 kb) aflatoxin pathway gene cluster, beyond the pksA gene at one end and the omtA gene at the other. Within the 25-kb genomic DNA sequence determined at the omtA end of the cluster, several new gene sequences were identified. The recently reported genes, vbs and ordA, were found within this 25-kb region. Two additional genes were also found in this region, a cytochrome P450 monooxygenase encoding gene, tentatively named cypX, and a monooxygenase encoding gene, tentatively named moxY, and these are also reported in this study. The sequence beyond these genes showed a 5-kb noncoding region of DNA followed by the presence of a cluster of genes probably involved in sugar metabolism. Northern blot analysis and reverse transcriptase-polymerase chain reaction (RT-PCR) studies demonstrated that the genes, cypX and MoxY are expressed concurrently with genes involved in aflatoxin biosynthesis. Therefore, the two putative aflatoxin pathway genes cypX and mox Y followed by a 5-kb non-coding region of DNA define one end of the boundary of the aflatoxin pathway gene cluster in A, parasiticus.

Yu, J., S. M. Mohawed, et al. (2003). "Substrate-induced lipase gene expression and aflatoxin production in Aspergillus parasiticus and Aspergillus flavus." Journal of Applied Microbiology 95(6): 1334-1342. ://000186563100021 Aims: To establish a relationship between lipase gene expression and aflatoxin production by cloning the lipA gene and studying its expression pattern in several aflatoxigenic and nontoxigenic isolates of Aspergillus flavus and A. parasiticus. Methods and Results: We have cloned a gene, lipA, that encodes a lipase involved in the breakdown of lipids from aflatoxin-producing A. flavus, A. parasiticus and two nonaflatoxigenic A. flavus isolates, wool-1 and wool-2. The lipA gene was transcribed under diverse media conditions, however, no mature mRNA was detected unless the growth medium was supplemented with 0.5% soya bean or peanut oil or the fungus was grown in lipid-rich medium such as coconut medium. The expression of the lipase gene (mature mRNA) under substrate-induced conditions correlated well with aflatoxin production in aflatoxigenic species A. flavus(SRRC 1007) and A. parasiticus (SRRC 143). Conclusions: Substrate-induced lipase gene expression might be indirectly related to aflatoxin formation by providing the basic building block acetate for aflatoxin synthesis. No direct relationship between lipid metabolism and aflatoxin production can be ascertained, however, lipase gene expression correlates well with aflatoxin formation. Significance and Impact of the Study: Lipid substrate induces and promotes aflatoxin formation. It gives insight into genetic and biochemical aspects of aflatoxin formation.

Yu, J. J., D. Bhatnagar, et al. (2004). "Completed sequence of aflatoxin pathway gene cluster in Aspergillus parasiticus." Febs Letters 564(1-2): 126-130. ://000221032000021 An 82-kb Aspergillus parasiticus genomic DNA region representing the completed sequence of the well-organized aflatoxin pathway gene cluster has been sequenced and annotated. In addition to the 19 reported and characterized aflatoxin pathway genes and the four sugar utilization genes in this cluster, we report here the identification of six newly identified genes which are putatively involved in aflatoxin formation. The function of these genes, the cluster organization and its significance in gene expression are discussed. (C) 2004 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

Yu, J. J., J. W. Cary, et al. (1993). "Cloning and Characterization of a Cdna from Aspergillus- Parasiticus Encoding an O-Methyltransferase Involved in Aflatoxin Biosynthesis." Applied and Environmental Microbiology 59(11): 3564-3571. ://A1993ME66000007 Aflatoxins are polyketide-derived secondary metabolites produced by the fungi Aspergillus flavus and Aspergillus parasiticus. Among the catalytic steps in the aflatoxin biosynthetic pathway, the conversion of sterigmatocystin to O- methylsterigmatocystin and the conversion of dihydrosterigmatocystin to dihydro-O-methylsterigmatocystin are catalyzed by an S-adenosylmethionine-dependent O- methyltransferase. A cDNA library was constructed by using RNA isolated from a 24-h-old culture of wild-type A. parasiticus SRRC 143 and was screened by using polyclonal antiserum raised against a purified 40-kDa O-methyltransferase protein. A clone that harbored a full-length cDNA insert (1,460 bp) containing the 1,254-bp coding region of the gene omt-1 was identified by the antiserum and isolated. The complete cDNA sequence was determined, and the corresponding 418-amino-acid sequence of the native enzyme with a molecular weight of 46,000 was deduced. This 46-kDa native enzyme has a leader sequence of 41 amino acids, and the mature form of the enzyme apparently consists of 377 amino acids and has a molecular weight of 42,000. Direct sequencing of the purified mature enzyme from A. parasiticus SRRC 163 showed that 19 of 22 amino acid residues were identical to the amino acid residues in an internal region of the deduced amino acid sequence of the mature protein. The 1,460-bp omt-1 cDNA was cloned into an Escherichia coli expression system; a Western blot (immunoblot) analysis of crude extracts from this expression system revealed a 51-kDa fusion protein (fused with a 5-kDa beta-galactosidase N- terminal fragment). Furthermore, enzymatic activity assays of the E. coli crude extracts showed that sterigmatocystin was converted to 0-methylsterigmatocystin in the presence of S- adenosylmethionine. A 1.5-kb omt-1 gene transcript was detected by Northern (RNA) blot analysis in total RNAs isolated from submerged A. parasiticus cultures grown in a medium which induces aflatoxin B, production that were 24, 48, 72, and 96 h old but not in RNA from a culture that was 18 h old. Transcript accumulation correlated well with the increased rate of aflatoxin accumulation in these cultures. A comparison of the predicted amino acid sequence of O-methyltransferase with previously described sequences revealed a proposed S- adenosylmethionine-binding site motif found in other S- adenosylmethionine- dependent methyltransferases.

Yu, J. J., P. K. Chang, et al. (2000). "Cloning of a sugar utilization gene cluster in Aspergillus parasiticus." Biochimica Et Biophysica Acta-Gene Structure and Expression 1493(1-2): 211-214. ://000089294600026 At one end of the 70 kb aflatoxin biosynthetic pathway gene cluster in Aspergillus parasitictus and Aspergillus flavus reported earlier, we have cloned a group of four genes that constitute a well-defined gene cluster related to sugar utilization in A. parasiticus: (1) sugR, (2) hxtA, (3) glcA and (4) nadA. No similar well-defined sugar gene cluster has been reported so far in any other related Aspergillus species such as A. flavus, A. nidulcans, A. sojae, A. niger, A. oryzae and A. fumigatus. The expression of the hxtA gene, encoding a hexose transporter protein, was found to be concurrent with the aflatoxin pathway cluster genes, in aflatoxin-conducive medium. This is significant since a close linkage between the two gene clusters could potentially explain the induction of aflatoxin biosynthesis by simple sugars such as glucose or sucrose. (C) 2000 Published by Elsevier Science B.V.

Yu, J. J., P. K. Chang, et al. (2003). "Cloning and functional expression of an esterase gene in Aspergillus parasiticus." Mycopathologia 156(3): 227-234. ://000182274300012 Within the 80 kb aflatoxin pathway gene cluster characterized earlier, and between adhA and norA genes, we have identified an estA gene encoding an esterase from wild type strain Aspergillus parasiticus SRRC 143. The 1,500 bp genomic DNA and 945 bp cDNA sequences were determined for estA. Outside of the aflatoxin pathway gene cluster, an additional copy of the estA gene (named estA2) was also cloned from the same A. parasiticus strain. Comparison of the estA and estA2 sequences showed 9 substitutions within the 314 amino acid residues of their gene products, and no apparent defect was identified in the estA2. The estA gene is a homolog of the stcI gene identified in A. nidulans involved in the biosynthesis of sterigmatocystin and dihydro-sterigmatocystin for the conversion of versiconal hemiacetal acetate to versiconal. Reverse-transcriptase polymerase chain reaction (RT-PCR) experiments demonstrated that the estA is constitutively expressed. And only this estA gene, which is located within the aflatoxin pathway gene cluster, is expressed; no expression of the estA2 gene was detected under both aflatoxin conducive and non- conducive conditions. Possible reasons for the preferential expression of the estA over the estA2 gene have been discussed.

Yu, J. J., P. K. Chang, et al. (1997). "avnA, a gene encoding a cytochrome P-450 monooxygenase, is involved in the conversion of averantin to averufin in aflatoxin biosynthesis in Aspergillus parasiticus." Applied and Environmental Microbiology 63(4): 1349-1356. ://A1997WR16200025 Recent studies have shown that at least 17 genes involved in the aflatoxin biosynthetic pathway are clustered within a 75-kb DNA fragment in the genome of Aspergillus parasiticus. Several additional transcripts have also been mapped to this gene cluster, A gene, avnA (previously named ord-l), corresponding to one of the two transcripts identified earlier between the ver-1 and omtA genes on the gene cluster was sequenced, The nucleotide sequence of the avnA gene contains a coding region for a protein of 495 amino acids with a calculated molecular mass of 56.3 kDa, The gene consists of three exons and two introns, Disruption of the avnA gene in the wild-type aflatoxigenic A, parasiticus strain (SU1-N3) resulted in a nonaflatoxigenic mutant which accumulated a bright yellow pigment, Thin-layer chromatographic studies with six different solvent systems showed that the migration patterns of the accumulated metabolite were identical to those of averantin, a known aflatoxin precursor. Precursor feeding studies with this mutant showed that norsolorinic acid and averantin were not converted to aflatoxin whereas 5'-hydroxyaverantin averufanin, averufin, versicolorin A, sterigmatocystin, and O- methylsterigmatocystin were converted to aflatoxins, Southern blot analysis of the wild-type strain and avnA-disrupted mutant strain indicated that the avnA gene was disrupted in the mutant strain. A search of the GenBank database for similarity indicated that the avnA gene encodes a cytochrome P-450-type monooxygenase, and it has been assigned to a new P-450 gene family named CYP60A1, We have therefore concluded that the avnA gene encodes a fungal cytochrome P-450-type enzyme which is involved in the conversion of averantin to averufin in the aflatoxin biosynthetic pathway in A. parasiticus.

Yu, J. J., P. K. Chang, et al. (1995). "Comparative Mapping of Aflatoxin Pathway Gene Clusters in Aspergillus-Parasiticus and Aspergillus-Flavus." Applied and Environmental Microbiology 61(6): 2365-2371. ://A1995RA62100046 Aflatoxins are toxic and carcinogenic secondary metabolites produced by the fungi Aspergillus flavus and A. parasiticus. Aflatoxins are synthesized by condensation of acetate units; their synthesis is estimated to involve at least 16 different enzymes. In this study we have shown that at least nine genes involved in the aflatoxin biosynthetic pathway are located within a 60-kb DNA fragment. Four of these genes, nor-1, aflR, ver-1, and omtA (previously named omt-1), have been cloned in A. flavus and A. parasiticus. In addition, five other genes, pksA, uvm8, aad, ord-1, and ord-2 have been recently cloned in A. parasiticus. The pksA, aad, and uvm8 genes exhibit sequence homologies to polyketide synthase, aryl-alcohol dehydrogenase, and fatty acid synthase genes, respectively. The cDNA sequences of ord-1 and ord-2 genes, which may be involved in later steps of aflatoxin biosynthesis, have been determined; the ord-1 gene prc,duct exhibits homology to cytochrome P-450-type enzymes. By characterizing the overlapping regions of the DNA inserts in different cosmid and lambda DNA clones, we have determined the order of these aflatoxin pathway genes within this 60-kb DNA region to be pksA, nor-1, uvm8, aflR, aad, ver-1, ord-1, ord-2, and omtA in A. parasiticus and nor-1, aflR, ver-1, ord-1, ord- 2, and omtA in A. flavus. The order is related to the order in enzymatic steps required for aflatoxin biosynthesis. The physical distances (in kilobase pairs) and the directions of transcription of these genes have been determined for both aflatoxigenic species.

Yu, J. J., P. K. Chang, et al. (2004). "Clustered pathway genes in aflatoxin biosynthesis." Applied and Environmental Microbiology 70(3): 1253- 1262. ://000220154800001

Yu, J. J., P. K. Chang, et al. (1998). "Characterization of the critical amino acids of an Aspergillus parasiticus cytochrome P-450 monooxygenase encoded by ordA that is involved in the biosynthesis of aflatoxins B-1, G(1), B-2, and G(2)." Applied and Environmental Microbiology 64(12): 4834-4841. ://000077396700031 The conversion of O-methylsterigmatocystin (OMST) and dihydro- O-methylsterigmatocystin to a aflatoxins B-1, G(1), B-2, and G(2) requires a cytochrome P-450 type of oxidoreductase activity. ordA, a gene adjacent to the omtA gene, was identified in the aflatoxin-biosynthetic pathway gene cluster by chromosomal walking in Aspergillus parasiticus, The ordA gene was a homolog of the Aspergillus flavus ord1 gene, which is involved in the conversion of OMST to aflatoxin B-1. Complementation of A. parasiticus SRRC 2043, an OMST- accumulating strain, with the ordA gene restored the ability to produce aflatoxins B-1, G(1), B-2, and G(2). The ordA gene placed under the control of the GAL1 promoter converted exogenously supplied OMST to aflatoxin B-1 in Saccharomyces cerevisiae. In contrast, the ordA gene homolog in A. parasiticus SRRC 2043, ordA1, was not able to carry out the same conversion in the yeast system. Sequence analysis revealed that the ordA1 gene had three point mutations which resulted in three amino acid changes (His-400-->Leu-400, Ala-143-->Ser-143, and Ile-528-->Tyr-528). Site-directed mutagenesis studies showed that the change of His-400 to Leu-400 resulted in a loss of the monooxygenase activity and that Ala-143 played a significant role in the catalytic conversion, In contrast, Ile- 528 was not associated with the enzymatic activity, The involvement of the ordA gene in the synthesis of aflatoxins G(1), and G(2) in A. parasiticus suggests that enzymes required fur the formation of aflatoxins G(1) and G(2) are not present in A. flavus. The results showed that in addition to the conserved heme-binding and redox reaction domains encoded by ordA, other seemingly domain-unrelated amino acid residues are critical for cytochrome P-450 catalytic activity. The ordA gene has been assigned to a new cytochrome P-450 gene family named CYP64 by The Cytochrome P450 Nomenclature Committee.

Yu, J. J., P. K. Chang, et al. (1995). "Comparison of the Omta Genes Encoding O-Methyltransferases Involved in Aflatoxin Biosynthesis from Aspergillus-Parasiticus and Aspergillus-Flavus." Gene 163(1): 121-125. ://A1995RY32400020 O-methyltransferase (OMT) is one of the key enzymes in aflatoxin (AF) biosynthesis in the fungi, Aspergillus flavus (Af) and A. parasiticus (Ap). Genomic DNA clones containing the omtA genes from Ap strain SRRC 143 and Af strain CRA01-2B were sequenced. Comparison of the genomic DNA sequences with the cDNA of this Ap gene revealed the presence of four introns ranging from 52 to 60 bp in length in both species; the region encoding the putative S-adenosylmethionine-binding motif was located between the third and fourth introns. The coding sequence of omtA from Ap strain SRRC 143 demonstrated a greater than 97% sequence identity with that from Af strain CRA01-2B, within the coding region.

Yu, J. J., C. P. Woloshuk, et al. (2000). "Cloning and characterization of avfA and omtB genes involved in aflatoxin biosynthesis in three Aspergillus species." Gene 248(1-2): 157-167. ://000087111700017 and http://www.botanischergarten.ch/Mycotoxins/Yu-Cloning-Aflatox-biosynth-2000b.pdf The biosynthesis of aflatoxins (B-1, G(1), B-2, and G(2)) is a multi-enzyme process controlled genetically by over 20 genes. In this study, we report the identification and characterization of the avfA gene, which was found to be involved in the conversion of averufin (AVF) to versiconal hemiacetal acetate (VHA), in Aspergillus parasiticus and A. flavus; a copy of avfA gene was also cloned from a non- aflatoxin producing strain A. sojae. Complementation of an averufin-accumulating, non-aflatoxigenic mutant strain of A. parasiticus, SRRC 165, with the avfA gene cloned from A. flavus, restored the ability of the mutant to convert AVF to VHA and to produce aflatoxins B-1, G(1), B-2, and G(2). Sequence analysis revealed that a single amino acid replacement from aspartic acid to asparagine disabled the function of the enzyme in the mutant strain SRRC 165. The A. parasiticus avfA was identified to be a homolog of previously sequenced, but functionally unassigned transcript, stcO, in A. nidulans based on sequence homology at both nucleotide (57%) and amino acid (55%) levels. In addition to avfA, another aflatoxin pathway gene, omtB, encoding for an O- methyltransferase involved in the conversion of demethylsterigmatocystin (DMST) to sterigmatocystin (ST) and dihydrodemethylsterigmatocystin (DHDMST) to dihydrosterigmatocystin (DHST), was cloned from A. parasiticus, A. flavus, and A. sojae. The omtB gene was found to be highly homologous to stcP from A. nidulans, which has been reported earlier to be involved in a similar enzymatic step for the sterigmatocystin formation in that species. RT-PCR data demonstrated that both the avfA and avfA1 as well as omtB genes in A. parasiticus were expressed only in the aflatoxin- conducive medium. An analysis of the degrees of homology for the two reported genes between the Aspergillus species A. parasiticus, A. flavus, A. nidulans and A. sojae was conducted. Published by Elsevier Science B.V. All rights reserved.

Zeringue, H. J. (2000). "Identification and effects of maize silk volatiles on cultures of Aspergillus flavus." Journal of Agricultural and Food Chemistry 48(3): 921-925. ://000086026000056 Volatiles generated from corn silks of individual genotypes of maize were found to exhibit differences in biological activities when the volatiles were exposed to 5-day solid cultures of Aspergillus flavus. In inverted potato dextrose- agar Petri plate bioassays, it was found that volatiles emitted from silks of the different maize genotypes had a profound effect on the growth of the fungus and, consequently, aflatoxin production. To determine the underlying cause for this bioactivity, volatiles emitted from the maize silks were trapped on Tenax glass columns and were analyzed by GO-MS. Aflatoxin field-resistant maize genotypes exhibited a larger relative concentration of the antifungal aldehyde, furfural (2- furancarboxaldehyde), when compared to the relative concentrations of the field-susceptible varieties tested. In a closed-container 5-day study, it was observed that fresh 1-and C-day-old corn silk samples of aflatoxin-resistant maize genotypes emitted higher concentrations of furfural compared to those from susceptible genotypes. This observation probably explains the reason for the bioactivity observed in the in vitro bioassays, and the presence of furfural appears to contribute to a defense mechanism for protecting the developing maize kernel from fungal attack.

Zeringue, H. J. and D. Bhatnagar (1990). "Inhibition of Aflatoxin Production in Aspergillus-Flavus Infected Cotton Bolls after Treatment with Neem (Azadirachta- Indica) Leaf Extracts." Journal of the American Oil Chemists Society 67(4): 215-216. ://A1990DA43800005

Zeringue, H. J. and D. Bhatnagar (1994). "Effects of Neem Leaf Volatiles on Submerged Cultures of Aflatoxigenic Aspergillus-Parasiticus." Applied and Environmental Microbiology 60(10): 3543-3547. ://A1994PK26600010 Microbe-free compressed air was passed continuously for a S-day test period through an enclosed system containing fresh neem leaves; the resultant emitted volatiles were passed over the surface of submerged liquid cultures of a wild-type aflatoxigenic isolate of Aspergillus parasiticus. Aflatoxin determinations for the fungal culture that received neem- derived volatiles, after a 3-day incubation period, resulted in a 90% overall reduction in aflatoxin production and a 51% reduction in fungal biomass when compared with cultures that did not receive neem volatiles. In a separate experiment but in a similarly enclosed system, volatiles from fresh neem leaves were collected on a small Tenax column and were thermally desorbed and cryogenically focused on a capillary gas chromatography column. The neem volatiles-were subsequently separated and identified by gas chromatography-mass spectrometry. Sixty-eight compounds were identified by comparison of retention times and mass spectra with either authentic compounds or spectra from a computer-assisted library database of mass spectra. It was found that 10% of the total headspace volatiles were composed of C-3 to C-9 alkenals, which are toxic to aflatoxigenic Aspergillus spp., which could explain the bioactivity that resulted in reduced biomass in the neem-treated cultures.

Zeringue, H. J., D. Bhatnagar, et al. (1993). "C15h24 Volatile Compounds Unique to Aflatoxigenic Strains of Aspergillus-Flavus." Applied and Environmental Microbiology 59(7): 2264-2270. ://A1993LL31000041 Headspace volatiles from eight strains of Aspergillus flavus (four aflatoxigenic strains and four nonaflatoxigenic strains), grown for 1, 2, 3, 4, 8, and 10 days in submerged cultures, were collected in Tenax GC traps. The traps were desorbed onto a 50-m gas-liquid chromatography capillary column by heat and gas purge from an external direct injector device. The column was interfaced with a mass spectrometer data acquisition system. Peaks were identified by comparing retention times and mass spectra with those obtained from authentic compounds and by using a computer-assisted mass spectral data base. Aflatoxigenic strains of A. flavus produced several C15H24 compounds (e.g., alpha-gurjunene, trans-caryophyllene, and cadinene) which peaked in 3-day cultures and were not present in earlier (1- and 2-day) or later (8- and 10-day) cultures. None of these volatiles were detected in nonaflatoxigenic strains of A. flavus. There was an apparent correlation between the release of C15H24 volatile compounds and the initiation of aflatoxin biosynthesis, and a correlation between decline of aflatoxin synthesis and the disappearance of the C15H24 compounds unique to aflatoxigenic A. flavus also existed.

Zeringue, H. J., B. Y. Shih, et al. (2001). "Effects of clarified neem oil on growth and aflatoxin B-1 formation in submerged and plate cultures of aflatoxigenic Aspergillus spp." Phytoparasitica 29(4): 361-366. ://000170618600008 An increase of 11-31% of dry mycelial mass was observed along with a slight decrease (5-10%) in aflatoxin B-1 production in 5-day- old aflatoxigenic Aspergillus spp, submerged cultures containing either 0.5 ml or 1.0 mi clarified neem oil (CNO) in 0.1% Triton solution. Fungal growth and aflatoxin B-1 production were also determined in potato-dextrose-agar petri plate cultures inoculated with aflatoxigenic Aspergillus spp. containing an atmosphere of volatiles emitted from 0.25 ml, 0.5 ml, and 1.0 ml CNO added to the plates. After 5 days' incubation, fungal radial growth was reduced by 7-29% and aflatoxin B-1 production by 0-67%. GC/MS analysis of the head space volatiles of the CNO indicated that the reduction of fungal growth and aflatoxin B-1 was probably due to low molecular weight hydrocarbons, aldehydes, alcohols, and sulfur compounds emitted at 30 degreesC in the dry culture. These results suggest that volatiles emitted from CNO at 30 degreesC in plate cultures were more fungistatic and consequently inhibited aflatoxin production more than neem oil added in liquid cultures.

Zollitsch, W., C. Raffaseder, et al. (2003). "Impact of the mycotoxins moniliformin and beauvericin on growth and carcass traits of broilers." Wiener Tierarztliche Monatsschrift 90(9): 238-243. ://000185983500002 In a feeding trial with broilers, the effects of diets containing different levels of the mycotoxins moniliformin and beauvericin on growth, carcass traits, chemical composition of carcasses and meat quality were analysed. A total of 180 day- old broiler chicks were divided into four treatments with three replicates (3 pens with 15 broilers each). Maize grain which was contaminated with moniliformin and beauvericin after inoculation on the field was included into the rations of group 1 (control), 2, 3 and 4 at a rate of 0, 5, 10 and 15%, respectively. Diets consisted of maize grain, soybean meal, maize gluten feed, dehydrated grass meal, meat meal, oil and mineral and vitamin premix and contained 21.1% crude protein, 1.21% lysine, 0.88% methionine + cysteine, 13.19 MJ/kg ME, 1.01% calcium, 0.70% phosphorus and 0.12% sodium. At the age of 37 days the chickens of treatments 1, 2, 3 and 4 had live masses of 1,779, 1,771, 1,764 and 1,743 g, respectively. The feed conversion ratios were 1.82, 1.79, 1.81, and 1.88, respectively. The diets containing moniliformin and beauvericin had no significant effect on growth, carcass traits and chemical composition of the carcass. No residues of mycotoxins could be detected in carcasses and selected internal organs. Heterogeneous results were observed for the organoleptic meat quality, the differences were independent of the dietary concentration of mycotoxins. The results of the present study indicate that dosages of up to 2.7 mg/kg and 12 mg/kg of diet of moniliformin and beauvericin, respectively, coming from natural contamination on the field show no effect on any of the traits observed here. Nevertheless all measures should be taken to avoid the contamination of broiler diets with mycotoxins because of the possibility of negative effects on performance and product quality that may be caused by higher mycotoxin contents in maize following severe fungi infections.

Zonno, M. C. and M. Vurro (1999). "Effect of fungal toxins on germination of Striga hermonthica seeds." Weed Research 39(1): 15-20. ://000079402500002 Fourteen fungal toxins were assayed in vitro to evaluate their effect on seed germination of the parasitic weed Striga hermonthica. Among them, T-2 toxin proved to be the most active, being able to inhibit 100% seed germination at 10(-5) M, and being still active when tested at a concentration of 10(-7) M (19% inhibition). Deoxinivalenol was also very active, causing 100% and 69% reduction in germination when assayed at 10(-4) and 10(-5) M respectively. Cytochalasin E, tenuazonic acid, fumonisin B-1, enniatin and nivalenol were shown to have an inhibitory effect of around 50% at 10(-4) M, whereas other toxins had lower or no activity. The high activity shown by some fungal toxins suggests that they may have potential for use as more natural and safe herbicides to suppress parasite seed germination.