DOCSLIB.ORG

Acaricidal Activity of Some Essential Oils and Their Constituents Against Tyrophagus Longior, a Mite of Stored Food

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Acaricidal Activity of Some Essential Oils and Their Constituents Against Tyrophagus Longior, a Mite of Stored Food Journal of Food Protection, Vol. 58, No.5, Pages 560-563 Copyrighl©, International Association of Milk, Food and Environmental Sanitarians Acaricidal Activity of Some Essential Oils and Their Constituents against Tyrophagus longior, a Mite of Stored Food STEF ANIA PERRUCCI* Dipartimento di Patologia Animale Profilassied Igiene degli Alimenti, Viale delle Piagge 2, Pisa, Italy 56/24 Downloaded from http://meridian.allenpress.com/jfp/article-pdf/58/5/560/1665363/0362-028x-58_5_560.pdf by guest on 24 September 2021 (MS# 94-226: Received 23 September 1994/Accepted 5 January 1995) ABSTRACT In addition, the presence of a large number of these pests in stored food can cause gastroenteric problems in Essential oils of four plants (two species of lavender, pepper- animals and humans ingesting them. Some authors report mint, and a eucalyptus) and some of their principal constituents, that biscuits and meal infested by Tyrophagus putrescentiae i.e., linalool, linalyl acetate, fenchone, menthone, menthol, and have caused diarrhea in dogs (6); moreover, other eucalyptol, were tested in vitro for their acaricidal activity against Tyrophagus longior, a mite species that is a pest in stored food. Tyrophagus species have caused gastrointestinal disorders Two different procedures were carried out to test the activity of in consumers of stored cheeses (5, 24). Storage mites are these compounds by direct contact and by inhalation. In the direct also frequently reported as being the etiological agents of contact assays five different quantities of each undiluted substance several allergic diseases in subjects coming into contact (6, 2, I, 0.5, and 0.25 J.ll) were spread on the internal surface of with them. Czernecki and Kraus (2) speak about an out- 6-cm petri dishes, each containing 10 mites. The activity by break of allergic dermatitis in a butcher's family caused by inhalation was tested using two petri dishes of different sizes: the Tyrophagus dimidatus, while T. longior was recorded by smaller one (6 cm), containing 10 mites, was covered with a filter- Rimbaud (21) as the cause of a severe canine dermatitis paper disk and enclosed in a bigger dish (9 cm) containing 6 oz with pruritus and alopecia. Allergic rhinitis and asthma 2 J.ll of each undiluted substance. At the highest doses, the essential oils of the two lavender species and of peppermint killed caused by storage mites are frequently reported worldwide 100% of the mites, both by direct contact and by inhalation. in farming communities and among cheese workers and Eucalyptus oil was the least active. Among the essential oil children (4,9,10,11,20,29). constituents, menthol showed the highest activity, killing 100% of These are some of the reasons why we need a means the mites at the lowest dose (0.25 J.ll) by direct contact and at 6 to control mites infestation of stored food. In addition, the J.ll by inhalation. However, Iinalool, fenchone, and menthone also development of drug resistance reported by some authors showed good acaricidal activity. Eucalyptol, like the essential oil (27,31) for T. longior and other Tyrophagus species justi- of which it is the principal constituent, had the lowest activity. fies the search for new effective acaricidal compounds. This study, part of more extensive research on the Key words: Essential oils, terpenes, Tyrophagus longior, acaricidal activity employment of new natural compounds to control arthropods, evaluates the acaricidal activity on T. longior of The high frequency of drug resistance of arthropods to the essential oils of two species of lavender (Lavandula pesticides and the problems of environmental safety due to angustifolia Miller and Lavandula stoechas L.), peppermint the persistence of these drugs and to their widespread use (Mentha x piperita L.), and a eucalyptus (Eucaliptus globulus in the agricultural and zootechnical fields (12,21,22,25) Labill.), and of some terpenes (linalool, linalyl acetate, illustrate why alternative means to fight dangerous acari menthone, menthol, and eucalyptol), which are their princi- and insects are needed. pal constituents (19). The killing activity of essential oils In this preliminary study we evaluated in vitro the acari- and their constituents on several arthropod species has cidal activity of some natural compounds against T. longior previously been reported; among them spearmint oil, (Gervais, 1844), an acarid species commonly found on menthone, and linalool were found to kill Dermatophagoides stored food (7,23). pteronyssinus, Dermatophagoides farinae, and T. putre- Among the mites that infest stored food, there are scentiae, mites closely related to T. longior (13). Hink and several species belonging to the genus Tyrophagus. These Duffy (8) found that linalool is an insecticide against ticks mites normally live on the external surface of seasoned and fleas. In some previous studies we have demonstrated hams, sausages, and cheeses, but sometimes they get into the acaricidal activity of the essential oil of L. angustifolia these products, causing the commercial exclusion of stored and of linalool against Psoroptes cuniculi, both by direct products (3,24,30). contact (17) and by inhalation (18). JOURNAL OF FOOD PROTECT/ON, VOL 58, MAY 1995 MATERIALS AND METIIODS Acaricidal activity by inhalation Mites (lO/plate) were placed in 6-cm petri dishes covered Essential oils with filter paper disks that allowed gas exchange; each plate so Flowering tops of Mentha x piperita (peppermint) plant prepared was inserted in a 9-cm petri dish containing the tested materials, harvested from a cultivated area located at substance and closed with the usual cover. After 24 h all immobile Sansepolcro (Ditta Aboca, Arezzo, Italy), were dried and mites were transferred to a sterile 6-cm petri dish. Each pure processed by hydrodistillation, using an apparatus (a Clevenger-like substance was used at 6 and 2 Ill; only menthol was dissolved device) according to Italian and European pharmacopoeia methods (20%) in vaseline oil. (Farmacopea Ufticiale, 1985), in order to extract its essential oil. The temperature, relative humidity, controls, and evaluation The essential oils of the two lavender species (Lavandula angustifolia of the acaricidal activity were the same as above. Each test was Miller and Lavandula stoechas L.) and of the eucalyptus (Eucaliptus repeated six times. The results are reported as the mean percent- globulus Labill.) were commercial samples (Ditta Primavera, Pisa). age of the mortality plus or minus the standard deviation of the six All the essential oils were analyzed using a Perkin-Elmer replicates. 8420 gas chromatograph equipped with a DB-Wax capillary column (30 m by 0.25 mm). The oven temperature was RESULTS AND DISCUSSION programmed as follows: first isotherm 60°C for 10 min, then up to 220°C at 5°C/min, and finally isotherm 220°C for 10 Table I shows the chemical composition of the oils Downloaded from http://meridian.allenpress.com/jfp/article-pdf/58/5/560/1665363/0362-028x-58_5_560.pdf by guest on 24 September 2021 min. The temperatures of the injector and detector were tested, analyzed by gas chromatography. 250°C. The carrier gas was nitrogen at 2 ml/min flow. The On the basis of the length of the body, the morphology detector was a flame ionization detector. The essential oil was of the fourth tarsus, and the male genital opening, the mites dissolved (I %) in diethyl ether (Et,O) and I III of this isolated from the ham were identified as belonging to the solution was injected using the split -technique (26). Peaks species Tyrophagus longior (Gervais, 1844). This acarid were identified by comparing the ,retention times to those of authentic samples, by means of their relative retention times species has been frequently isolated from ham, numerous with respect to two internal standards (cellosolve acetate and kinds of cheeses, and other foodstuffs (7, 23). butyl cellosolve), and by means of the reliability factors Table 2 shows the acaricidal activity by direct contact method (16). and by inhalation found for each essential oil and each constituent. The percentage of mortality of the control Constituents of essential oils mites was always very low in all the tests (6.7 to 10%). The main constituents of the essential oils tested were L angustifolia, L stoechas, and Mentha x piperita essential respectively linalool and linalyl acetate for the L. angustifolia oils, tested for their activity by direct contact, were able to oil, fenchone for the L. stoechas oil, menthone and menthol for the Mentha x piperita oil, and I, 8-cineole (eucalyptol) for E. globulus oil. They were all purchased from Aldrich (Sigma- TABLE I. Chemical composition of the essential oils (%). Aldrich Szl via Gallarate 154,20151 Milano, Italy). Principal Lavandula Mentha Lavandula Eucalyptus Mites components angustifolia piperita stoechas globulus Mites isolated from samples of seasoned Parma ham were microscopically identified using the keys and descrip- a-Pinene 0.14 0.44 3.68 6.60 tions of Robertson (23). At least 20 pairs of adult male and Camphene 0.10 0.91 female mites were confined in individual 9-cm petri dishes ~-Pinene 0.11 0.61 0.11 0.30 containing two slices (2 by 2 by 2 cm) of uninfested Parma ham. All Myrcene 0.64 tr 0.25 0.33 plates were placed in a controlled chamber (A. Gallenkarnp & Co., Limonene 0.20 0.60 2.35 5.73 Ltd., London) at 25°C and 70% relative humidity. In this way it was Eucalyptol 1.06 4.00 3.58 76.00 possible to obtain an in vitro culture (27). y-Terpinene tt' 0.15 0.78 The adult stages of the mites could be recognized and p-Cymene 9.05 0.51 1.02 selected from the culture by the presence of four pairs of legs, Fenchone 47.23 a stronger color, and a greater length.
Load more

Recommended publications
  • Retention Indices for Frequently Reported Compounds of Plant Essential Oils
    Retention Indices for Frequently Reported Compounds of Plant Essential Oils V. I. Babushok,a) P. J. Linstrom, and I. G. Zenkevichb) National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA (Received 1 August 2011; accepted 27 September 2011; published online 29 November 2011) Gas chromatographic retention indices were evaluated for 505 frequently reported plant essential oil components using a large retention index database. Retention data are presented for three types of commonly used stationary phases: dimethyl silicone (nonpolar), dimethyl sili- cone with 5% phenyl groups (slightly polar), and polyethylene glycol (polar) stationary phases. The evaluations are based on the treatment of multiple measurements with the number of data records ranging from about 5 to 800 per compound. Data analysis was limited to temperature programmed conditions. The data reported include the average and median values of retention index with standard deviations and confidence intervals. VC 2011 by the U.S. Secretary of Commerce on behalf of the United States. All rights reserved. [doi:10.1063/1.3653552] Key words: essential oils; gas chromatography; Kova´ts indices; linear indices; retention indices; identification; flavor; olfaction. CONTENTS 1. Introduction The practical applications of plant essential oils are very 1. Introduction................................ 1 diverse. They are used for the production of food, drugs, per- fumes, aromatherapy, and many other applications.1–4 The 2. Retention Indices ........................... 2 need for identification of essential oil components ranges 3. Retention Data Presentation and Discussion . 2 from product quality control to basic research. The identifi- 4. Summary.................................. 45 cation of unknown compounds remains a complex problem, in spite of great progress made in analytical techniques over 5.
    [Show full text]
  • Antibacterial Activity and Mechanism of Linalool Against Shewanella Putrefaciens
    molecules Article Antibacterial Activity and Mechanism of Linalool against Shewanella putrefaciens Fengyu Guo 1,2,3, Qiong Liang 1, Ming Zhang 1, Wenxue Chen 1,2,3, Haiming Chen 1,2,3 , Yonghuan Yun 1,2,3 , Qiuping Zhong 1,2,3,* and Weijun Chen 1,2,3,* 1 College of Food Science and Technology, Hainan University, Haikou 570228, China; [email protected] (F.G.); [email protected] (Q.L.); [email protected] (M.Z.); [email protected] (W.C.); [email protected] (H.C.); [email protected] (Y.Y.) 2 Key Laboratory of Food Nutrition and Functional Food of Hainan Province, Haikou 570228, China 3 Hainan Provincial Engineering Research Center of Aquatic Resources Efficient Utilization in the South China Sea, Haikou 570228, China * Correspondence: [email protected] (Q.Z.); [email protected] (W.C.) Abstract: The demand for reduced chemical preservative usage is currently growing, and natural preservatives are being developed to protect seafood. With its excellent antibacterial properties, linalool has been utilized widely in industries. However, its antibacterial mechanisms remain poorly studied. Here, untargeted metabolomics was applied to explore the mechanism of Shewanella putrefaciens cells treated with linalool. Results showed that linalool exhibited remarkable antibacterial activity against S. putrefaciens, with 1.5 µL/mL minimum inhibitory concentration (MIC). The growth of S. putrefaciens was suppressed completely at 1/2 MIC and 1 MIC levels. Linalool treatment reduced the membrane potential (MP); caused the leakage of alkaline phosphatase (AKP); and released the DNA, RNA, and proteins of S. putrefaciens, thus destroying the cell structure and expelling the cytoplasmic content.
    [Show full text]
  • Liquid−Liquid Extraction of Linalool from Methyl Eugenol with 1-Ethyl-3-Methylimidazolium
    Open Chem., 2019; 17: 564–570 Research Article Tuğba Erkoç, Lutfullah M. Sevgili*, Selva Çavuş* Liquid−Liquid Extraction of Linalool from Methyl Eugenol with 1-Ethyl-3-methylimidazolium Hydrogen Sulfate [EMIM][HSO4] Ionic Liquid https://doi.org/10.1515/chem-2019-0067 received January 22, 2018; accepted January 9, 2019. present such as membrane separation [3], pervaporation [3] and extraction [4]. Because of the significant Abstract: The liquid–liquid equilibrium (LLE) data for advantages of ionic liquids, they have a great potential a ternary system {methyl eugenol + linalool +1-ethyl-3- to be investigated for extraction and other separation methylimidazolium hydrogen sulfate [EMIM][HSO4]} processes [5, 6]. Detailed economic analysis of hydrogen (Meu-Lin-IL) were measured at 298.2 K and atmospheric sulfate based ILs was performed [7]. It was reported that pressure. The Othmer–Tobias correlation was used to large volume-IL based applications may be commercially verify the reliability of the experimental tie-line data. The feasible and also, ILs can be as inexpensive as typical solubility curves were obtained using the cloud point organic solvents [7]. Studies on the liquid-liquid titration indicating the liquid-liquid equilibrium of the extraction with ionic liquids showed that ionic liquid ternary system was in Type II class where two immiscible is an efficient solvent for the separation process. [8-14]. curve pairs were attained. Distribution coefficients, ILs can easily be synthesized with a conceivable cost separation factors and selectivity were calculated for [9] and ILs also have advantages in terms of economy the immiscibility regions. The calculated results were such as decrease in purification steps and reduced compared with the experimental data.
    [Show full text]
  • Mechanistic Insights on Skin Sensitization to Linalool
    Mechanistic insights on skin sensitization to linalool hydroperoxides: EPR evidence on radical intermediates formation in reconstructed human epidermis and 13 C-NMR reactivity studies with thiol residues Salen Kuresepi, Bertrand Vileno, Jean-Pierre Lepoittevin, Corresponding Author, Elena Giménez-Arnau To cite this version: Salen Kuresepi, Bertrand Vileno, Jean-Pierre Lepoittevin, Corresponding Author, Elena Giménez- Arnau. Mechanistic insights on skin sensitization to linalool hydroperoxides: EPR evidence on radical intermediates formation in reconstructed human epidermis and 13 C-NMR reactivity stud- ies with thiol residues. Chemical Research in Toxicology, American Chemical Society, 2020, 10.1021/acs.chemrestox.0c00125. hal-02624525 HAL Id: hal-02624525 https://hal.archives-ouvertes.fr/hal-02624525 Submitted on 26 May 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Mechanistic insights on skin sensitization to linalool hydroperoxides: EPR evidence on radical intermediates formation in reconstructed human epidermis and 13C-NMR reactivity studies
    [Show full text]
  • Essential Oil Flavours and Fragrances
    Authenticating Essential Oil Flavours and Fragrances Using Enantiomeric Composition Analysis A report for the Rural Industries Research and Development Corporation by Professor RC Menary and Ms SM Garland University of Tasmania October 1999 RIRDC Publication No 99/125 RIRDC Project No UT-15A i © 1999 Rural Industries Research and Development Corporation All rights reserved. ISBN 0 642 57906 7 ISSN 1440-6845 Authenticating Essential Oil Flavours and Fragrances - Using Enantiomeric Composition Analysis Publication no 99/125 Project no.UT-15A The views expressed and the conclusions reached in this publication are those of the author and not necessarily those of persons consulted. RIRDC shall not be responsible in any way whatsoever to any person who relies in whole or in part on the contents of this report. This publication is copyright. However, RIRDC encourages wide dissemination of its research, providing the Corporation is clearly acknowledged. For any other enquiries concerning reproduction, contact the Publications Manager on phone 02 6272 3186. Researcher Contact Details Prof. Robert C. Menary Ms Sandra M. Garland School of Agricultural Science University of Tasmania GPO Box 252 C Hobart Tas 7001 Phone: (03) 6226 6723 Fax: (03) 6226 7609 RIRDC Contact Details Rural Industries Research and Development Corporation Level 1, AMA House 42 Macquarie Street BARTON ACT 2600 PO Box 4776 KINGSTON ACT 2604 Phone: 02 6272 4539 Fax: 02 6272 5877 Email: [email protected] Website: http://www.rirdc.gov.au Published in October 1999 Printed on environmentally friendly paper by Canprint ii Foreword The introduction of international standards to quantify and qualify properties of essential oils has seen the increasing application of analytical technology.
    [Show full text]
  • Essential Oil Composition of Thymus Vulgaris L. and Their Uses
    Journal of Research & Development, Vol. 11 (2011) ISSN 0972-5407 Essential Oil Composition of Thymus Vulgaris L. and their Uses Shazia Shabnum1,2 and Muzafar G. Wagay1,*2 1,2. Department of Bio-technology, Rayalaseema University, Kurnool (A.P) India, 1,*2. Bio-technoogy Division, Indian Institute of Integrative Medicine, Srinagar (J&K) ABSTRACT The composition of the essential oil from the Thymus vulgaris L. type growing wild in northern Italy were identified by GC/MS . Identified were thirty components, the main essential oils are as follows:- thymol, γ- terpinene, ρ-cymene, linalool, myrcene, α-pinene, eugenol, carvacrol and α -thujene. Among these twelve aroma constituents of thyme were examined for their antioxidant activities using the aldehyde/carboxylic assay. Eugenol, thymol, carvacrol and 4-allylphenol showed stronger antioxidant activities than did other components tested in the assay. Twenty one essential oils were tested for insecticidal activity against spodoptera litura. Carvacrol has shown mutagenecity. ρ -cymene, linalool, terpinene -4-ol and thymol exhibited antifungal activity against Botrytis Cinerea and Rhizopus Stolonifer, two common storage pathogens of strawberries (Fragaria ananassa). Effects of thymol on the spontaneous contractile activity have been found in in-vitro experiments with circular smooth muscle strips from guinea pig stomach and vena portae. Thymol was found to possess an agonistic effect on α1-α2 and β-adrenergic receptors. Thymol has shown analgesic effect through its action on the α2 adrenergic receptors of the nerve cells. Key words: Thymus vulgaris L., essential oil, composition, smooth muscle fibres, α1-α2 and -adrenergic receptors, natural anti oxidants, Fragaria ananassa, Rosaceae, volatile components, antifungal, Botrytis cinerea, Rhizopus stolonifer, Spodoptera litura 83 Journal of Research & Development, Vol.
    [Show full text]
  • Dietary Compounds for Targeting Prostate Cancer
    Review Dietary Compounds for Targeting Prostate Cancer Seungjin Noh 1, Eunseok Choi 1, Cho-Hyun Hwang 1, Ji Hoon Jung 2, Sung-Hoon Kim 2 and Bonglee Kim 1,2,* 1 College of Korean Medicine, Kyung Hee University, Seoul 02453, Korea; [email protected] (S.N.); [email protected] (E.C.); [email protected] (C.-H.H.) 2 Department of Pathology, College of Korean Medicine, Graduate School, Kyung Hee University, Seoul 02453, Korea; [email protected] (J.H.J.); [email protected] (S.-H.K.) * Correspondence: [email protected]; Tel.: +82-2-961-9217 Received: 10 August 2019; Accepted: 17 September 2019; Published: 8 October 2019 Abstract: Prostate cancer is the third most common cancer worldwide, and the burden of the disease is increased. Although several chemotherapies have been used, concerns about the side effects have been raised, and development of alternative therapy is inevitable. The purpose of this study is to prove the efficacy of dietary substances as a source of anti-tumor drugs by identifying their carcinostatic activities in specific pathological mechanisms. According to numerous studies, dietary substances were effective through following five mechanisms; apoptosis, anti-angiogenesis, anti- metastasis, microRNA (miRNA) regulation, and anti-multi-drug-resistance (MDR). About seventy dietary substances showed the anti-prostate cancer activities. Most of the substances induced the apoptosis, especially acting on the mechanism of caspase and poly adenosine diphosphate ribose polymerase (PARP) cleavage. These findings support that dietary compounds have potential to be used as anticancer agents as both food supplements and direct clinical drugs.
    [Show full text]
  • Transient Receptor Potential Channels and Metabolism
    Molecules and Cells Minireview Transient Receptor Potential Channels and Metabolism Subash Dhakal and Youngseok Lee* Department of Bio and Fermentation Convergence Technology, Kookmin University, BK21 PLUS Project, Seoul 02707, Korea *Correspondence: [email protected] https://doi.org/10.14348/molcells.2019.0007 www.molcells.org Transient receptor potential (TRP) channels are nonselective Montell, 2007). These cationic channels were first charac- cationic channels, conserved among flies to humans. Most terized in the vinegar fly, Drosophila melanogaster. While TRP channels have well known functions in chemosensation, a visual mechanism using forward genetic screening was thermosensation, and mechanosensation. In addition to being studied, a mutant fly showed a transient response to being sensing environmental changes, many TRP channels constant light instead of the continuous electroretinogram are also internal sensors that help maintain homeostasis. response recorded in the wild type (Cosens and Manning, Recent improvements to analytical methods for genomics 1969). Therefore, the mutant was named as transient recep- and metabolomics allow us to investigate these channels tor potential (trp). In the beginning, researchers had spent in both mutant animals and humans. In this review, we two decades discovering the trp locus with the germ-line discuss three aspects of TRP channels, which are their role transformation of the genomic region (Montell and Rubin, in metabolism, their functional characteristics, and their 1989). Using a detailed structural permeation property anal- role in metabolic syndrome. First, we introduce each TRP ysis in light-induced current, the TRP channel was confirmed channel superfamily and their particular roles in metabolism. as a six transmembrane domain protein, bearing a structural Second, we provide evidence for which metabolites TRP resemblance to a calcium-permeable cation channel (Mon- channels affect, such as lipids or glucose.
    [Show full text]
  • Linalool Cas No
    SUMMARY OF DATA FOR CHEMICAL SELECTION LINALOOL CAS NO. 78-70-6 BASIS OF NOMINATION TO THE CSWG The nomination of linalool to the CSWG is based on high production volume, widespread human exposure, and an unknown potential for adverse health effects from long-term administration. Linalool came to the attention of the CSPG because of information supplied by the Food and Drug Administration (FDA) from a review of “GRAS” substances used as spices and food additives. According to the FDA data, linalool is found in 63 different spices. It is also a common flavoring in beverages and foods and has widespread use in cosmetics. North American consumption in the flavor and fragrance industry alone has been estimated to be 2.2 million lbs. Occupational exposure to linalool in the United States is significant, estimated to be nearly 250,000 workers in 106 industries. Linalool is found in herbs, other plants, and in household and pet products, helping to account for its widespread occurrence in the environment. Although virtually every person in the United States has some degree of exposure to linalool, no studies in humans or experimental animals were found that address or identify the chronic effects of linalool. SELECTION STATUS ACTION BY CSWG : 7/16/97 Studies requested : - Metabolism studies - Mechanistic studies to include examination of the role of _2u -globulin in transport - Carcinogenicity - In vitro cytogenetic analysis - In vivo micronucleus assay Priority : High Rationale/Remarks : - High production levels Widespread exposure as an ingredient in natural products and as an environmental pollutant - Lack of chronic toxicity data - Test in parallel with citronellol INPUT FROM GOVERNMENT AGENCIES/INDUSTRY Dr.
    [Show full text]
  • Generated by SRI International Pathway Tools Version 25.0, Authors S
    Authors: Pallavi Subhraveti Ron Caspi Quang Ong Peter D Karp An online version of this diagram is available at BioCyc.org. Biosynthetic pathways are positioned in the left of the cytoplasm, degradative pathways on the right, and reactions not assigned to any pathway are in the far right of the cytoplasm. Transporters and membrane proteins are shown on the membrane. Ingrid Keseler Periplasmic (where appropriate) and extracellular reactions and proteins may also be shown. Pathways are colored according to their cellular function. Gcf_000725805Cyc: Streptomyces xanthophaeus Cellular Overview Connections between pathways are omitted for legibility.
    [Show full text]
  • RSC Advances
    RSC Advances View Article Online PAPER View Journal | View Issue One-pot synthesis at room temperature of epoxides and linalool derivative pyrans in Cite this: RSC Adv., 2020, 10, 7691 monolacunary Na7PW11O39-catalyzed oxidation reactions by hydrogen peroxide† a b b Castelo B. Vilanculo, * Marcio´ J. Da Silva, Milena Galdino Teixeira and Jesus Avendano Villarrealc In this work, we describe a new one-pot synthesis route of valuable linalool oxidation derivatives (i.e., 2-(5- methyl-5-vinyltetrahydrofuran-2-yl propan-2-ol) (1a)), 2,2,6-trimethyl-6-vinyltetrahydro-2H-pyran-3-ol (1b) and diepoxide (1c), using a green oxidant (i.e., hydrogen peroxide) under mild conditions (i.e., room temperature). Lacunar Keggin heteropolyacid salts were the catalysts investigated in this reaction. Among Received 2nd January 2020 them, Na PW O was the most active and selective toward oxidation products. All the catalysts were Accepted 25th January 2020 7 11 39 characterized by FT-IR, TG/DSC, BET, XRD analyses and potentiometric titration. The main reaction Creative Commons Attribution-NonCommercial 3.0 Unported Licence. DOI: 10.1039/d0ra00047g parameters were assessed. Special attention was dedicated to correlating the composition and rsc.li/rsc-advances properties of the catalysts and their activity. 1. Introduction In this regard, to develop oxidative routes of linalool based on hydrogen peroxide, an inexpensive, atom-efficient and green The oxidation of terpenic alcohols, which are an abundant, oxidant that generates only water as a by-product is a challenge
    [Show full text]
  • Development of a Process for the Preparation of Linalool from Cis -2-Pinanol
    1 DEVELOPMENT OF A PROCESS FOR THE PREPARATION OF LINALOOL FROM CIS -2-PINANOL Subash Ramnarain Buddoo Thesis submitted in fulfilment of the requirements for the degree DOCTOR TECHNOLOGIAE In the faculty of Applied Science at the NELSON MANDELA METROPOLITAN UNIVERSITY June 2008 Promoter : Prof. B. Zeelie Co-promoter : Dr. J. Dudas 2 ACKNOWLEDGEMENTS The author wishes to express his sincere appreciation to: • My promoters, Prof. B. Zeelie and Dr. J. Dudas for their assistance, guidance and encouragement to conclude this project; • The Department of Science and Technology for funding the project under the Support Programme for Industrial Innovation (SPII); • The THRIP fund for providing funds for the purchase of equipment required for the laboratory experimental investigations; • Teubes Pty. Ltd. for financial support, provision of starting material (CST and α-pinene) and for permission to use this material for a thesis; • S. Farnworth for the management of the CST project; • N. Siyakatshana for his assistance with the reaction kinetics and computer modelling of the process; • B. Cowan for assistance with the GC-MS analysis; and • My wife (Shelina), son (Kavish) and daughter (Sarisha) for their encouragement, patience and tolerance. 3 SUMMARY Linalool is a key intermediate for the production of important fragrance chemicals such as geraniol, nerol, geranial, and neral. Linalool can be produced via a two-step process from α-pinene which is a major component of crude sulphated turpentine (CST) a foul-smelling, volatile waste product of the pulp and paper industry. The key step in this process is the pyrolysis step which involves the isomerisation of cis -2- pinanol to linalool and requires high temperatures (600-650°C) and is not very selective due to the decomposition of the product itself under these conditions.
    [Show full text]