Tannin Management in the Vineyard

Total Page:16

File Type:pdf, Size:1020Kb

Tannin Management in the Vineyard Fact Sheet MaY 2010 tannin Management in the Vineyard Author: Dr Mark Downey Group Leader, Plant Production Sciences, Mildura Senior Research Scientist, Viticulture & Oenology cwrdc GRAPE AND WINE RESEARCH AND DEVELOPMENT CORPORA TION c 210mm tannin ManaGeMent in the VineYaRd Fact Sheet MaY 2010 What is tannin? extension subunits can be any of the flavan-3-ols, but in most studies of grapes, catechin is the common terminal subunit and tannins are bitter and astringent compounds found in most epicatechin is the most common extension subunit. Published plants. they are polyphenolic research suggests that grape compounds that fall into two polymers range in length up to 30- classes, hydrolysable and condensed 40 subunits. tannins. there are many hundreds of There are TWO classes of in grapes, condensed tannins are individual compounds, but they have tannins, HYDROLYSABLE present in high concentration in the a few things in common. all tannins seeds and skins, but are also present bind protein, which is the basis of and CONDENSED tannins in the leaves and stems. tannins are their role in tanning hides for leather also present in wood, but become and gave rise to their name. this bound to cell walls and other phenolics during lignification and property of binding tannin also gives rise to the term astringent are not easily extracted. from the Latin, ad astringere, “to bind”. Roles of tannin Measurement of tannin tannins play two defensive roles, one against micro-organisms there are many methods for measuring tannin. Most methods and the other against herbivores. in both cases tannins bind measure phenolics, rather than tannins. the most common to protein making it unavailable as a nitrogen source. tannins phenolic measure is absorbance at 280nm (a280). as a also bind to cell walls and other phenolics to create a defensive surrogate for tannins it is quite poor because it assumes that barrier when cell integrity is lost. Being bitter and astringent, most of what was measured by a280 is tannin, which is often their taste is a deterrent to herbivores. not the case. all of the small non-tannin phenolic compounds absorb at 280nm, as do anthocyanins, flavonols, proteins, and RNA & DNA. a number of methods are based on stains that hydrolysable tannins react with tannins with varying degrees of specificity. these hydrolysable tannins include: dMACA (dimethylcinnamaldehyde), vanillin-HCL, Folin- include gallotannins denis, Folin-ciocalteau and iron chloride (Fecl3). Some of these and ellagitannins. methods are quite reproducible, but they assume non-tannin Gallotannins are made material is either insignificant or at least constant; there isn’t up of gallic acid bound good evidence for either assumption. to a sugar molecule, eg. the French method and the Butanol-HCL method rely on boiling pentagalloyl-glucose. the tannin in acid to produce the coloured anthocyanidin ellagitannins are precursors to anthocyanins. this approach is useful because it complexes of gallic acid. will release bound tannin. however, the lack of standards make hydrolysable tannins hydrolysable tannins, showing gallic acid, it difficult to quantify. are primarily derived and pentagalloyl glucose (gallotannin) as from wood. well as ellagic acid and an ellagitannin Protein precipitation assays are well established and robust. polymeric complex. Some, like haeme analysis that required blood have lost favour, but gelatine and albumin assays are still common. currently in condensed tannin grape and wine research, precipitation with BSa (bovine serum condensed tannins, also know as proanthocyanidins, are albumin) is widely used in research and numerous wineries polymeric compounds made up of flavan-3-ols subunits. the in the USa. Because tannin will also bind polysaccharides, flavan-3-ols are based on a three ring structure, the flavan precipitation with methylcellulose has also been quite extensively skeleton, and have an alcohol (Oh) at position 3 on ring c used by the australian Wine Research institute (aWRi). of the flavan. Further modifications of the flavan give rise to thin-layer chromatography (tLc) has also been used, but different flavan-3-ols. requires tannin extraction and purification prior to separation. in grapes, these include the method is good for monomers, although these are in low catechin, epicatechin, abundance relative to polymers, which appear as a blob or epicatechin-gallate and smear depending on solvent choice. the separated spots require epigallocatechin. the visualisation by a reagent such as DAMCA or Fecl and can be biosynthesis of flavan- 3 difficult to quantify. 3-ols is well-studied, but the mechanism of high-performance liquid chromatography (hPLc) is widely polymer formation is used as a research tool and some wineries also employ this unknown. the flavan- technology. the equipment is costly and requires a skilled 3-ols can be combined technician to operate and in-depth knowledge of tannins a generic condensed tannin structure to interpret the data. hPLc methods are either based on in different sequences showing terminal an extension subunits and and proportions in the ring labelling and carbon numbering separating monomers from the tannin “blob” similar to tLc or tannin polymers. convention for the flavan skeleton rely on depolymerising the tannin with acid and separating the (uppermost extension subunit). individual subunits. there are also some hPLc methods that condensed tannin separate polymers based on size. polymers have a terminal subunit and a series of extension subunits linked by an More recently, rapid analytical methods that don’t require inter-flavan bond; a bond between flavan units. the terminal and chemical analysis have been developed, but are not yet ready for 210mm widespread adoption. For industry, the BSa and methylcellulose acids (eg, caffeic acid, resveratrol). this pathway also makes the precipitation methods are most accessible. precursors for lignin (wood) production. during berry development the main phase of tannin tannins in wine accumulation is between flowering and veraison. Studies conducted in tannins contribute to the mouthfeel McLaren Vale (South australia) on and colour stability of wine. the colour The most accessible Shiraz skin showed a high level of of grapes and of young red wine is method for Australian tannin at flowering followed by a due to the presence of anthocyanins. period of tannin synthesis towards anthocyanins are structurally similar to wineries to measure tannin veraison, after which tannin levels tannins, but are relatively unstable. in declined towards harvest. From wine they breakdown or interact with is the methylcellulose season to season there was variation other elements to form new compounds, method offered by AWRI. in the timing of the peak in tannin some of which are coloured. accumulation, but generally this the largest single class of the coloured was accepted as the typical pattern of tannin accumulation compounds in older wines are the pigmented polymers. in grape skin. however, samples collected from the Sunraysia Polymeric pigments are tannin polymers with anthocyanins region of northwest attached. there is limited information on the structure of Victoria showed a very pigmented polymers or their formation in wine. Pigmented different pattern with polymers are only formed during winemaking not in the grape. the peak in tannin occurring at fruit-set Because tannins are bitter and astringent they contribute to the and declining from mouthfeel of the wine. tannins precipitate the salivary proteins then on. this pattern that lubricate the mouth and make it easy to chew and swallow was seen in Shiraz, food. this causes the drying and puckering sensation associated cabernet Sauvignon with drinking red wine. in addition to protein, tannins also and chardonnay skin interact with polysaccharides in saliva as well as cells in the oral over several seasons cavity. these interactions are impacted upon by the alcohol and indicates a strong the pattern of tannin accumulation in skin of concentration and viscosity of the wine and can be masked by Shiraz berries from two regions, Sunraysia (nW regional effect on residual sugar and other flavour and aroma characters, such as Victoria) and McLaren Vale (South australia) tannin accumulation fruit intensity. the perception of mouthfeel is also affected by during berry development. in grapes. tannin concentration, polymer length and polymer composition. We know that epicatechin-gallate is perceived as coarser than epicatechin, while epigallocatechin is perceived as smoother, Variation between varieties however the sensory character of oligomers and polymers anecdotal evidence indicates significant differences in tannin and combinations of tannins and other elements such as levels between grape polysaccharides is unknown. varieties, with some varieties considered tannins added to wine high in tannins, eg. tannat and nebbiolo, While winemakers recognise there are tannins in grapes, often and others low in the level of extracted from the grapes is not sufficient for a tannin, eg. Merlot particular wine style, so it is common practice to add tannin to and Barbera. wine during fermentation or aging. the main reasons for adding tannin are to stabilise colour or to alter mouthfeel. a study of grape Variation in total skin tannins (mg/g FWt skin) skin tannins from 36 the tannins that are added to the wine can come from oak between varieties. cultivars showed that barrels, chips and staves (hydrolysable tannin), or can come many of the cultivars
Recommended publications
  • A Comparison of the Production of Polyphenol Contents and the Expression of Genes Involved in Vietnamese Tea Cultivars
    International Food Research Journal 26(6): 1781-1788 (December 2019) Journal homepage: http://www.ifrj.upm.edu.my A comparison of the production of polyphenol contents and the expression of genes involved in Vietnamese tea cultivars 1Hoang, T. T. Y., 2Luu, H. L., 2Nguyen, T. L., 3Duong, T. D., 4,5Nguyen, H. D. and 2*Huynh, T. T. H 1Thai Nguyen University of Sciences, Thai Nguyen University, Thai Nguyen Province 24000, Vietnam 2Institute of Genome Research, Vietnam Academy of Science and Technology (VAST), Hanoi 100000, Vietnam 3Thai Nguyen University of Agriculture and Forestry, Thai Nguyen University, Thai Nguyen Province 24000, Vietnam 4Advanced Centre for Bioorganic Chemistry, Institute of Marine Biochemistry, VAST, Hanoi 100000, Vietnam 5University of Science and Technology of Hanoi, VAST, Hanoi 100000, Vietnam Article history Abstract Received: 19 June, 2019 Tea (Camellia sinensis) is a popular health beverage which is consumed all over the world Received in revised form: due to its good aroma and taste. Tea consumption is also considered to reduce the risk of 16 September, 2019 several diseases in humans, including cardiovascular diseases, diabetes and cancers. Recent Accepted: 25 September, 2019 studies have shown that polyphenols derived from tea may contribute to the majority of these pharmaceutical properties. Among all the tea polyphenols, catechins are the main components that include (−)-epicatechin (EC), (−)-epicatechin gallate (ECG), (−)-epigallocatechin (EGC), (−)-epigallocatechin-3 gallate (EGCG), (+)-catechin (C), (−)-catechin gallate (CG), (−)-gallocatechin (GC), and (−)-gallocatechingallate (GCG). In the present work, four Keywords catechins (C, EGC, ECG, and EGCG) and two anthocyanidins (cyanidin 3-O-glucoside and delphinidin 3-O-glucoside) in two Vietnamese tea cultivars, Trungduxanh and Trungdutim, were Catechin LAR quantitatively detected by high-performance liquid chromatography.
    [Show full text]
  • Tannins: Current Knowledge of Food Sources, Intake, Bioavailability and Biological Effects
    S310 DOI 10.1002/mnfr.200900039 Mol. Nutr. Food Res. 2009, 53, S310 – S329 Review Tannins: Current knowledge of food sources, intake, bioavailability and biological effects Jos Serrano1, Riitta Puupponen-Pimi2, Andreas Dauer3, Anna-Marja Aura2 and Fulgencio Saura-Calixto4 1 Universidad Complutense de Madrid, Depto. Nutricin y Bromatologa I, Madrid, Spain 2 VTT Technical Research Center of Finland 3 Hexal AG, Holzkirchen, Germany 4 Consejo Superior de Investigaciones Cientficas, Instituto del Frio, Depto. Metabolismo y Nutricin, Madrid, Spain Tannins are a unique group of phenolic metabolites with molecular weights between 500 and 30000 Da, which are widely distributed in almost all plant foods and beverages. Proanthocyanidins and hydrolysable tannins are the two major groups of these bioactive compounds, but complex tannins containing structural elements of both groups and specific tannins in marine brown algae have also been described. Most literature data on food tannins refer only to oligomeric compounds that are extracted with aqueous-organic solvents, but a significant number of non-extractable tannins are usu- ally not mentioned in the literature. The biological effects of tannins usually depend on their grade of polymerisation and solubility. Highly polymerised tannins exhibit low bioaccessibility in the small intestine and low fermentability by colonic microflora. This review summarises a new approach to analysis of extractable and non-extractable tannins, major food sources, and effects of storage and processing on tannin content and bioavailability. Biological properties such as antioxidant, antimicro- bial and antiviral effects are also described. In addition, the role of tannins in diabetes mellitus has been discussed. Keywords: Bioavailability / Diet / Hydrolysable tannins / Proanthocyanidins / Tannins / Received: November 27, 2007; revised: January 25, 2009; accepted: February 9, 2009 1 Introduction weight having the ability to complex strongly with carbohy- drates and proteins [9].
    [Show full text]
  • Mangifera Indica) Cultivars from the Colombian Caribbean
    Vol. 11(7), pp. 144-152, 17 February, 2017 DOI: 10.5897/JMPR2017.6335 Article Number: 94A673D62820 ISSN 1996-0875 Journal of Medicinal Plants Research Copyright © 2017 Author(s) retain the copyright of this article http://www.academicjournals.org/JMPR Full Length Research Paper Mangiferin content, carotenoids, tannins and oxygen radical absorbance capacity (ORAC) values of six mango (Mangifera indica) cultivars from the Colombian Caribbean Marcela Morales1, Santiago Zapata1, Tania R. Jaimes1, Stephania Rosales1, Andrés F. Alzate1, Maria Elena Maldonado2, Pedro Zamorano3 and Benjamín A. Rojano1* 1Laboratorio Ciencia de los Alimentos, Universidad Nacional de Colombia, Medellín, Colombia. 2Escuela de nutrición, Universidad de Antioquia, Medellín, Colombia. 3Graduate School, Facultad de Ciencias Agrarias, Universidad Austral de Chile, Chile. Received 18 January, 2017; Accepted 13 February, 2017 Mango is one of the tropical fruits of greater production and consumption in the world, and a rich source of bioactive compounds, with various functional properties such as antioxidant activity. In Colombia, mango’s market is very broad and diverse. However, there are very few studies that determined the content of bioactive secondary metabolites. The objective of this study was to evaluated the content of different metabolites like Mangiferin, carotenoids, tannins, and the antioxidant capacity by oxygen radical absorbance capacity (ORAC) methodology of six cultivars from the Colombian Caribbean region, with total carotenoid values ranging from 24.67 to 196.15 mg of β-carotene/100 g dry pulp; 84.30 to 161.49 mg Catequine eq./100 g dry pulp for the content of condensed tannins, and 91.80 to 259.23 mg/100 g dry pulp for mangiferin content.
    [Show full text]
  • Solutions That Meet Your Demands for Food Testing & Agriculture
    Solutions that meet your demands for food testing & agriculture Our measure is your success. Excellent choices for food & agriculture applications products I applications I software I services Agilent Technologies Consumer Products Toys, jewelry, clothing, and other products are frequently recalled due to the presence of unsafe levels of substances such as lead from paint and phthal- ates from product polymers and packaging. Whether your perspective is to guarantee your products are free of contaminants or you are screening for harmful contaminants in a wide variety of consumer products, Agilent Tech- nologies provides the tools you need to detect and measure these and other harmful contaminants. > Search entire document Agilent 1290 Infinity LC with Agilent Poroshell columns for simultaneous determination of eight organic UV filters in under two minutes Application Note Consumer Products Authors Siji Joseph Agilent Technologies India Pvt. Ltd. mAU Amino benzoic acid Bangalore, India 2 Oxybenzone 1.5 4-Methyl benzylidene camphor Dioxybenzone Avobenzone Michael Woodman 1 Octyl methoxycinnamate 0.5 Octocrylene Agilent Technologies, Inc. Octyl salicylate 2850 Centerville Road 0 0 0.5 1 1.5 2 min Wilmington DE 19808 USA Abstract Levels of UV filters in personal care products are regulated by the FDA and European Pharmacopeia (EP). Liquid chromatographic (LC) methods are widely accepted analyt- ical techniques for the qualitative and quantitative analysis of these UV filters. Most of these traditional LC methods require about 25–50 minutes. In this Application Note, the Agilent 1290 Infinity LC, in combination with Agilent Poroshell columns, were used for development of a short, sensitive, robust and well resolved separation of eight FDA/EP approved active UV filter ingredients in 99 seconds.
    [Show full text]
  • L.) Leaves Tao Jiang1,3, Kunyuan Guo2,3, Lingdi Liu1, Wei Tian1, Xiaoliang Xie1, Saiqun Wen1 & Chunxiu Wen1*
    www.nature.com/scientificreports OPEN Integrated transcriptomic and metabolomic data reveal the favonoid biosynthesis metabolic pathway in Perilla frutescens (L.) leaves Tao Jiang1,3, Kunyuan Guo2,3, Lingdi Liu1, Wei Tian1, Xiaoliang Xie1, Saiqun Wen1 & Chunxiu Wen1* Perilla frutescens (L.) is an important medicinal and edible plant in China with nutritional and medical uses. The extract from leaves of Perilla frutescens contains favonoids and volatile oils, which are mainly used in traditional Chinese medicine. In this study, we analyzed the transcriptomic and metabolomic data of the leaves of two Perilla frutescens varieties: JIZI 1 and JIZI 2. A total of 9277 diferentially expressed genes and 223 favonoid metabolites were identifed in these varieties. Chrysoeriol, apigenin, malvidin, cyanidin, kaempferol, and their derivatives were abundant in the leaves of Perilla frutescens, which were more than 70% of total favonoid contents. A total of 77 unigenes encoding 15 enzymes were identifed as candidate genes involved in favonoid biosynthesis in the leaves of Perilla frutescens. High expression of the CHS gene enhances the accumulation of favonoids in the leaves of Perilla frutescens. Our results provide valuable information on the favonoid metabolites and candidate genes involved in the favonoid biosynthesis pathways in the leaves of Perilla frutescens. Perilla frutescens (L.), which is a self-compatible annual herb, belongs to the family Lamiaceae. Tis species has been widely cultivated in China, Japan, and Korea for centuries. Perilla frutescens is an important medicinal and edible plant in China with medical and nutritional uses 1. Its leaves can be utilized as a transitional medicinal herb, as a vegetable, and as a spice, and its seeds can be processed into foods and nutritional edible oils 2.
    [Show full text]
  • Antioxidant Rich Extracts of Terminalia Ferdinandiana Inhibit the Growth of Foodborne Bacteria
    foods Article Antioxidant Rich Extracts of Terminalia ferdinandiana Inhibit the Growth of Foodborne Bacteria Saleha Akter 1 , Michael E. Netzel 1, Ujang Tinggi 2, Simone A. Osborne 3, Mary T. Fletcher 1 and Yasmina Sultanbawa 1,* 1 Queensland Alliance for Agriculture and Food Innovation (QAAFI), The University of Queensland, Health and Food Sciences Precinct, 39 Kessels Rd, Coopers Plains, QLD 4108, Australia 2 Queensland Health Forensic and Scientific Services, 39 Kessels Rd, Coopers Plains, QLD 4108, Australia 3 CSIRO Agriculture and Food, 306 Carmody Road, St Lucia, QLD 4067, Australia * Correspondence: [email protected]; Tel.: +617-344-32471 Received: 26 June 2019; Accepted: 20 July 2019; Published: 24 July 2019 Abstract: Terminalia ferdinandiana (Kakadu plum) is a native Australian plant containing phytochemicals with antioxidant capacity. In the search for alternatives to synthetic preservatives, antioxidants from plants and herbs are increasingly being investigated for the preservation of food. In this study, extracts were prepared from Terminalia ferdinandiana fruit, leaves, seedcoats, and bark using different solvents. Hydrolysable and condensed tannin contents in the extracts were determined, as well as antioxidant capacity, by measuring the total phenolic content (TPC) and free radical scavenging activity using the 2, 2-diphenyl-1-picrylhydrazyl (DPPH) assay. Total phenolic content was higher in the fruits and barks with methanol extracts, containing the highest TPC, hydrolysable tannins, and DPPH-free radical scavenging capacity (12.2 2.8 g/100 g dry weight ± (DW), 55 2 mg/100 g DW, and 93% respectively). Saponins and condensed tannins were highest in ± bark extracts (7.0 0.2 and 6.5 0.7 g/100 g DW).
    [Show full text]
  • Anthocyanins: Antioxidant And/Or Anti-Inflammatory Activities
    Journal of Applied Pharmaceutical Science 01 (06); 2011: 07-15 ISSN: 2231-3354 Anthocyanins: Antioxidant and/or anti-inflammatory Received on: 18-08-2011 Accepted on: 23-08-2011 activities M. G. Miguel ABSTRACT Anthocyanins are polyphenols with known antioxidant activity which may be responsible for some biological activities including the prevention or lowering the risk of cardiovascular disease, diabetes, arthritis and cancer. Nevertheless such properties, their stability and bioavailability depend M. G. Miguel on their chemical structure. In the present work a brief review is made on chemical structures, Faculdade de Ciências e Tecnologia, bioavailability and antioxidant/anti -inflammatory of anthocyanins. Departamento de Química e Farmácia, Centro de Biotecnologia Vegetal, Instituto de Biotecnologia e Key words: Anthocyanins, chemistry, stability, bioavailability, free radical scavenging. Bioengenharia, Universidade do Algarve, Campus de Gambelas, 8005- 139 Faro, PORTUGAL INTRODUCTION Anthocyanins are generally accepted as the largest and most important group of water- soluble pigments in nature (Harborne, 1998). They are responsible for the blue, purple, red and orange colors of many fruits and vegetables. The word anthocyanin derived from two Greek words: anthos, which means flowers, and kyanos, which means dark blue (Horbowicz et al., 2008). Major sources of anthocyanins are blueberries, cherries, raspberries, strawberries, black currants, purple grapes and red wine (Mazza, 2007). They belong to the family of compounds known as flavonoids, but they are distinguished from other flavonoids due to their capacity to form flavylium cations (Fig. 1) (Mazza, 2007). + O Fig 1. Flavylium cation. They occur principally as glycosides of their respective aglycone anthocyanidin- chromophores with the sugar moiety generally attached at the 3-position on the C-ring or the 5- position on the A-ring (Prior and Wu, 2006).
    [Show full text]
  • “Off” Flavors in Beer Their Causes & How to Avoid Them a Moremanual ™ Morebeer.Com 1–800–600–0033
    “Off” Flavors In Beer Their Causes & How To Avoid Them A MoreManual ™ MoreBeer.com 1–800–600–0033 Acetaldehyde puckering sensation, may feel powdery or metallic in the mouth, like sucking on a grape skin or a tea bag • Tastes/Smells Like: Green apples, rotten-apples, freshly cut pumpkin. • Possible Causes: Astringency can be caused by many different factors. Polyphenols or tannins are the • Possible Causes: Acetaldehyde is a naturally occurring number one cause of such flavors. Tannins are found chemical produced by yeast during fermentation. It is in the skins or husks of the grain as well as in the skin usually converted into Ethanol alcohol, although this of fruit. Steeping grain for too long or grain that has process may take longer in beers with high alcohol been excessively milled or crushed can release tan- content or when not enough yeast is pitched. Some nins. When mashing, if the pH exceeds 5.2–5.6, as- bacteria can cause green apple flavors as well. tringent flavors can be produced. Over-hopping can • How to Avoid: Let the beer age and condition over also lend a hand in creating astringent qualities. a couple months time. This will give the yeast time • How to Avoid: Avoid grain that has been “over-milled”. to convert the Acetaldehyde into Ethanol. Always use Grain should be cracked open but not crushed or high quality yeast and make sure you are pitching the shredded. When sparging, pay close attention to correct amount for the gravity of the wort or make a the temperature and the amount of the water used.
    [Show full text]
  • Fortified Mangrove Tannin-Based Plywood Adhesive
    Fortified Mangrove Tannin-Based Plywood Adhesive S. SOWUNMI,1 R. O. EBEWELE,1,* A. H. CONNER,2 AND B. H. RIVER2 1Department of Chemical Engineering, Ahmadu Bello University, Zaria, Nigeria; and 2Forest Products Laboratory, One Gifford Pinchot Drive, Madison, Wisconsin 53705 SYNOPSIS Mangrove bark tannin adhesives are based on a renewable resource. They are potential substitutes or supplements for phenol-formaldehyde (PF) wood-bonding adhesives which are derived from petroleum, a finite natural resource. However, mangrove tannin adhesives exhibit poor adhesive properties including poor wet strength, brittleness, and poor wood penetration. These problems were addressed by treating tannin extract with acetic anhydride and then sodium hydroxide followed by modification with 20% resole-type PF resin. Sig- nificant structural changes occurred after the chemical treatment. Heat of reaction of tannin with formaldehyde was increased while the activation energy was drastically reduced. Pre- mature cure was also reduced. The fortified formulations had good plywood adhesive prop- erties. 1996 John Wiley & Sons, Inc. INTRODUCTION poor wood penetration, and poor wet strength. Rea- sons advanced for these shortcomings inter alia in- 1,2,6,7 There have been several attempts to replace part of clude the following. the petroleum-derived phenolic compounds in wood bonding adhesives with phenolic-type compounds 1. The tannin molecules are big and therefore obtained from renewable sources. Principal among cannot rotate freely about their backbone. these efforts is the development of adhesives from This results in the observed inherent brittle- tannin. 1,2 Tannin-based adhesives have in the past ness. been heavily fortified with urea, urea-formaldehyde 2.
    [Show full text]
  • 6 Health Aspects and Antiaflatoxigenic Activity of Phytochemicals in Tree
    OF Health Aspects 6 and Antiaflatoxigenic Activity of Phytochemicals in Tree Nuts Russell]. Molyneux, Noreen Mahoney, long H. Kim, and Bruce C. Campbell CONTENTS 6.1 Introduction............................................................................................................................. 95 6.2 Aflatoxinsin Tree Nuts ........................................................................................................... 96 6.3 Allatoxin Resistance Phytochemicals in Tree Nuts................................................................97 6.3.1 Varietal Resistance of Tree Nut Species .....................................................................98 6.3.2 Antiaflatoxigenic Constituents in Specific Tissues .....................................................98 6.4 Isolation and Identification of Walnut Antiatlatoxigenic Constituents...................................99 6.4.1 Bioassay-Directed Fractionation .................................................................................99 6.4.2 Analysis of Hydrolysable Tannin Content in Walnuts ..............................................100 6.4.3 Gallic and Ellagic Acid Content in Tree Nuts...........................................................101 6.4.3.1 Variation of Gallic and Ellagic Acids with Maturity .................................101 6.4.3.2 Variation of Gallic and Ellagic Acids with Cultivar..................................101 6.4.3.3 Structure—Activity Relationships ...............................................................103 6.5 Mechanism
    [Show full text]
  • Use of Fire-Impacted Trees for Oriented Strandboards
    Use of fire-impacted trees for oriented strandboards Laura Moya✳ Jerrold E. Winandy✳ William T. Y. Tze✳ Shri Ramaswamy Abstract This study evaluates the potential use of currently unexploited burnt timber from prescribed burns and wildfires for oriented strandboard (OSB). The research was performed in two phases: in Phase I, the effect of thermal exposure of timber on OSB properties was evaluated. Jack pine (Pinus banksiana) trees variously damaged by a moderately intense prescribed burn in a northern Wisconsin forest were selected. Four fire-damage levels of wood were defined and processed into series of single-layer OSB. The flakes used in Phase I had all char removed. Mechanical and physical properties were evaluated in accordance with ASTM D 1037. Results showed that OSB engineering performance of all four fire-damage levels were similar, and their me­ chanical properties met the CSA 0437 requirements. In Phase II, we assessed OSB properties from fire-killed, fire-affected and virgin red pine (Pinus resinosa) trees from a central Wisconsin forest exposed to an intense wildfire. The effect of various thermal exposures and varying amounts of char on OSB performance were evaluated. Phase II findings indicate that fire-damage level and bark amount had significant effects on the board properties. Addition of 20 percent charred bark had an adverse effect on bending strength; however, OSB mechanical properties still met the CSA requirements for all fire levels. Conversely, bark addition up to 20 percent was found to improve dimension stability of boards. This study suggests that burnt timber is a promising alternative bio-feedstock for commercial OSB production.
    [Show full text]
  • A Guide to Medicinal Plants of Appalachia
    LACTUCA SCARZOLA L. (ASTERACEAE) COMMON NAMES: Prickly lettuce, compass plant, wild let- tuce, wild opium. DESCRIPTION: An annual or perennial that grows to 2 feet in height. Flowers are yellow, but purple or bluish when dried. Stem has a few prickles. Leaves are cleft, with lobes arranged on either side of a common axis. FLOWERING PERIOD: June to October. HABITAT: Cultivated fields, waste or disturbed areas, dry soil, and gardens. HARVEST: Leaves in summer or fall; milky juice of the stem in summer. USES: The milky juice of this plant is extremely irritating to the eyes. The whole herb has been used as a diuretic, antispasmodic, and emollient. LACTUCA SCARZOLA L. (ASTERACEAE) LEONURUS CARDZACA L. (LAM1ACEAE) COMMON NAMES: Motherwort, common motherwort, lion's ear, lion's tail, lion's tart, throwwort. DESCRIPTION: A perennial that grows to 3 to 6 feet in height. Stems are stout, with 2- to 5-inch long petioled leaves. The palmately lobed leaves have sharp teeth. Flowers are white to pink, and very hairy. FLOWERING PERIOD: May to August. HABITAT: Waste places, roadsides, gardens, and pastures. HARVEST: Herb at flowering time. USES: The herb is used as a stimulant and emmenagogue. In Europe it has been used to treat heart palpitations and asthma. LEONURUS CARDZACA L. (LAMIACEAE) LZNDERA BENZOIN (L.) BLUME (LAURACEAE) COMMON NAMES: Common spicebush, auspice bush, Benja- min bush, feverbush, spiceberry, spicebush, wild allspice. DESCRIPTION: A deciduous shrub that grows to more than, 15 feet in height. Leaves are 3 to 5 inches long, alternate, elliptical, aromatic, with smooth margins. Produces greenish- -yellow flowers in dense clusters and long, bright red berries.
    [Show full text]