Kinetic Study of Ester Biofuels in Flames Artëm Dmitriev
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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. -
Effect of Enzymes on Strawberry Volatiles During Storage, at Different Ripeness
Effect of Enzymes on Strawberry Volatiles During Storage, at Different Ripeness Level, in Different Cultivars and During Eating Thesis Presented in Partial Fulfillment of the Requirements for the Degree Master of Science in the Graduate School of The Ohio State University By Gulsah Ozcan Graduate Program in Food Science and Technology The Ohio State University 2010 Thesis Committee: Sheryl Ann Barringer, Adviser W. James Harper John Litchfield 1 Copyright by Gülşah Özcan 2010 ii ABSTRACT Strawberry samples with enzyme activity and without enzyme activity (stannous chloride added) were measured for real time formation of lipoxygenase (LOX) derived aroma compounds after 5 min pureeing using selected ion flow tube mass spectrometry (SIFT-MS). The concentration of (Z)-3-hexenal and (E)-2-hexenal increased immediately after blending and gradually decreased over time while hexanal concentration increased for at least 5 min in ground strawberries. The formation of hexanal was slower than the formation of (Z)-3-hexenal and (E)-2-hexenal in the headspace of pureed strawberries. The concentration of LOX aldehydes and esters significantly increased during refrigerated storage. Damaging strawberries increased the concentration of LOX aldehydes but did not significantly affect the concentration of esters. The concentrations of many of the esters were strongly correlated to their corresponded acids and/or aldehydes. The concentration of LOX generated aldehydes decreased during ripening, while fruity esters increased. Different varieties had different aroma profiles and esters were the greatest percentage of the volatiles. The aroma release of some of the LOX derived aldehydes in the mouthspace in whole strawberries compared to chopped strawberries showed that these volatiles are formed in the mouth during chewing. -
Bioelectronic Nose Based on Single-Stranded DNA And
nanomaterials Article Bioelectronic Nose Based on Single-Stranded DNA and Single-Walled Carbon Nanotube to Identify a Major Plant Volatile Organic Compound (p-Ethylphenol) Released by Phytophthora Cactorum Infected Strawberries Hui Wang 1,2,* , Yue Wang 1, Xiaopeng Hou 2 and Benhai Xiong 1,* 1 State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China; [email protected] 2 Research Institute of Wood Industry, Chinese Academy of Forestry, Beijing 100091, China; [email protected] * Correspondence: [email protected] or [email protected] (H.W.); [email protected] (B.X.); Tel.: +86-010-62811680 (B.X.) Received: 5 February 2020; Accepted: 3 March 2020; Published: 7 March 2020 Abstract: The metabolic activity in plants or fruits is associated with volatile organic compounds (VOCs), which can help identify the different diseases. P-ethylphenol has been demonstrated as one of the most important VOCs released by the Phytophthora cactorum (P. cactorum) infected strawberries. In this study, a bioelectronic nose based on a gas biosensor array and signal processing model was developed for the noninvasive diagnostics of the P.cactorum infected strawberries, which could overcome the limitations of the traditional spectral analysis methods. The gas biosensor array was fabricated using the single-wall carbon nanotubes (SWNTs) immobilized on the surface of field-effect transistor, and then non-covalently functionalized with different single-strand DNAs (ssDNA) through π–π interaction. The characteristics of ssDNA-SWNTs were investigated using scanning electron microscope, atomic force microscopy, Raman, UV spectroscopy, and electrical measurements, indicating that ssDNA-SWNTs revealed excellent stability and repeatability. -
Expanding the Modular Ester Fermentative Pathways for Combinatorial Biosynthesis of Esters from Volatile Organic Acids
ARTICLE Expanding the Modular Ester Fermentative Pathways for Combinatorial Biosynthesis of Esters From Volatile Organic Acids Donovan S. Layton,1,2 Cong T. Trinh1,2,3 1 Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, Tennessee 2 BioEnergy Science Center (BESC), Oak Ridge National Laboratory, Oak Ridge, Tennessee 3 Bredesen Center for Interdisciplinary Research and Graduate Education, University of Tennessee, Knoxville, Tennessee; telephone: þ865-974-8121; fax: 865-974-7076; e-mail: [email protected] Biotechnol. Bioeng. 2016;113: 1764–1776. ABSTRACT: Volatile organic acids are byproducts of fermentative ß 2016 Wiley Periodicals, Inc. metabolism, for example, anaerobic digestion of lignocellulosic KEYWORDS: modular chassis cell; carboxylate; ester; acyl acetate; biomass or organic wastes, and are often times undesired inhibiting acyl acylate; ester fermentative pathway cell growth and reducing directed formation of the desired products. Here, we devised a general framework for upgrading these volatile organic acids to high-value esters that can be used as flavors, fragrances, solvents, and biofuels. This framework employs the acid-to-ester modules, consisting of an AAT (alcohol Introduction acyltransferase) plus ACT (acyl CoA transferase) submodule and an alcohol submodule, for co-fermentation of sugars and organic Harnessing renewable or waste feedstocks (e.g., switchgrass, corn acids to acyl CoAs and alcohols to form a combinatorial library of stover, agricultural residue, or municipal solid waste) -
Reuse of Oak Chips for Modification of the Volatile Fraction of Alcoholic Beverages
LWT - Food Science and Technology 135 (2021) 110046 Contents lists available at ScienceDirect LWT journal homepage: www.elsevier.com/locate/lwt Reuse of oak chips for modification of the volatile fraction of alcoholic beverages Eduardo Coelho *, Jos´e A. Teixeira , Teresa Tavares , Lucília Domingues , Jos´e M. Oliveira CEB – Centre of Biological Engineering, University of Minho, 4710-057, Braga, Portugal ARTICLE INFO ABSTRACT Keywords: New or used barrels can be applied in ageing of alcoholic beverages. Compounds adsorbed in wood migrate Wood ageing between beverages along with wood extractives. As barrel ageing is costly and time-consuming, processes using Barrel alternatives wood fragments have been gaining interest. These generate wood residues for which the reuse is still not well Volatile compounds established. This work aims at the reuse of oak fragments for the additive ageing of alcoholic beverages. Oak Sensory properties chips, previously immersed in fortifiedwine, were applied to beer, wine and grape marc spirit. Wood compounds and adsorbed wine volatiles were extracted, with more impact and satisfactory yields on beer composition. Also, wood adsorbed beverages compounds in a subtractive ageing phenomena. Beer formulations using different binomial wood concentration/temperature combinations were generated and presented to trained tasters. Higher temperatures and wood concentrations led to prominence of wood descriptors and lower perception of fruity and floral aromas, reflecting the changes in chemical composition. 1. Introduction several other (Mosedale & Puech, 2003). During its lifecycle, cooperage wood can be used, reused, regenerated and eventually discarded. For Wood ageing is commonly used as a strategy to modify and enhance barrels, there is a well-established reuse flow depending on the aged the composition of alcoholic beverages. -
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Analytical Methods Accepted Manuscript This is an Accepted Manuscript, which has been through the Royal Society of Chemistry peer review process and has been accepted for publication. Accepted Manuscripts are published online shortly after acceptance, before technical editing, formatting and proof reading. Using this free service, authors can make their results available to the community, in citable form, before we publish the edited article. We will replace this Accepted Manuscript with the edited and formatted Advance Article as soon as it is available. You can find more information about Accepted Manuscripts in the Information for Authors. Please note that technical editing may introduce minor changes to the text and/or graphics, which may alter content. The journal’s standard Terms & Conditions and the Ethical guidelines still apply. In no event shall the Royal Society of Chemistry be held responsible for any errors or omissions in this Accepted Manuscript or any consequences arising from the use of any information it contains. www.rsc.org/methods Page 1 of 23 Analytical Methods 1 2 3 1 Analysis of volatile compounds in Capsicum spp. by headspace solid-phase 4 5 6 2 microextraction and GC×GC-TOFMS 7 8 3 Stanislau Bogusz Junior a, d *, Paulo Henrique Março b, Patrícia Valderrama b, Flaviana 9 10 c c c 11 4 Cardoso Damasceno , Maria Silvana Aranda , Cláudia Alcaraz Zini , Arlete Marchi 12 d e 13 5 Tavares Melo , Helena Teixeira Godoy 14 15 6 16 17 18 7 a Federal University of the Jequitinhonha and Mucuri (UFVJM), Institute of Science and 19 20 8 Technology, Diamantina, MG, Brazil. -
Dependent Modeling Approach Derived from Semi-Empirical Quantum Mechanical Calculations
3D-QSAR/QSPR Based Surface- Dependent Modeling Approach Derived From Semi-Empirical Quantum Mechanical Calculations 3D-QSAR/QSPR-basierter, oberflächenabhängiger Modellierungsansatz, abgeleitet von semi-empirischen quantenmechanischen Rechnungen Der Naturwissenschaftlichen Fakultät der Friedrich-Alexander-Universität Erlangen-Nürnberg Zur Erlangung des Doktorgrades Dr. rer. nat. vorgelegt von Marcel Youmbi Foka aus Kamerun Als Dissertation genehmigt von der Naturwissenschaftlichen Fakultät/ vom Fachbereich Chemie und Pharmazie der Friedrich-Alexander-Universität Erlangen-Nürnberg Tag der mündlichen Prüfung: 05.12.2018 Vorsitzender des Promotionsorgans: Prof. Dr. Georg Kreimer Gutachter/in: Prof. Dr. Tim Clark Prof. Dr. Birgit Strodel Dedication In memory of my late Mother Lucienne Metiegam, who the Lord has taken unto himself on May 3, 2009. My mother, light of my life, God rest her soul, had a special respect for my studies. She had always encouraged me to move forward. I sincerely regret the fact that today she cannot witness the culmination of this work. Maman, que la Terre de nos Ancêtres te soit légère! This is a special reward for Mr. Joseph Tchokoanssi Ngouanbe, who always supported me financially and morally. That he find here the expression of my deep gratitude. i ii Acknowledgements I would like to pay tribute to all those who have made any contribution, whether scientific or not, to help carry out this work. All my thanks go especially to Prof. Dr. Tim Clark, who gave me the opportunity and means to work in his research team. I am grateful to have had him not only supervise my work but also for his patience and for giving me the opportunity to explore this fascinating topic. -
Oral Release Behavior of Wine Aroma Compounds by Using In-Mouth Headspace Sorptive Extraction (HSSE) Method
foods Article Oral Release Behavior of Wine Aroma Compounds by Using In-Mouth Headspace Sorptive Extraction (HSSE) Method María Pérez-Jiménez, Carolina Muñoz-González and María Angeles Pozo-Bayón * Instituto de Investigación en Ciencias de la Alimentación (CIAL), CSIC-UAM, C/Nicolás Cabrera, 9, 28049 Madrid, Spain; [email protected] (M.P.-J.); [email protected] (C.M.-G.) * Correspondence: [email protected] Abstract: The oral release behavior of wine aroma compounds was determined by using an in-mouth headspace sorptive extraction (HSSE) procedure. For this, 32 volunteers rinsed their mouths with a red wine. Aroma release was monitored at three time points (immediately, 60 s, and 120 s) after wine expectoration. Twenty-two aroma compounds belonging to different chemical classes were identified in the mouth. Despite the large inter-individual differences, some interesting trends in oral release behavior were observed depending on the chemical family. In general, esters and linear alcohols showed rapid losses in the mouth over the three sampling times and therefore showed a low oral aroma persistence. On the contrary, terpenes, lactones, and C13 norisoprenoids showed lower variations in oral aroma release over time, thus showing a higher oral aroma persistence. Additionally, and despite their low polarity, furanic acids and guaiacol showed the highest oral aroma persistence. This work represents the first large study regarding in-mouth aroma release behavior after wine tasting, using real wines, and it confirmed that oral release behavior does not only Citation: Pérez-Jiménez, M.; depend on the physicochemical properties of aroma compounds but also on other features, such as Muñoz-González, C.; Pozo-Bayón, the molecular structure and probably, on the characteristics and composition of the oral environment. -
An Experimental and Kinetic Modeling Study of Premixed Laminar Flames of Methyl Pentanoate and Methyl Hexanoate
Z. Phys. Chem. 2015; aop Oleg P. Korobeinichev, Ilya E. Gerasimov, Denis A. Knyazkov, Andrey G. Shmakov, Tatyana A. Bolshova, Nils Hansen, Charles K. Westbrook*, Guillaume Dayma, and Bin Yang An Experimental and Kinetic Modeling Study of Premixed Laminar Flames of Methyl Pentanoate and Methyl Hexanoate Abstract: Detailed chemical structures of stoichiometric and rich premixed lam- inar flames of methyl pentanoate and methyl hexanoate were investigated over a flat burner at 20 Torr and for methyl pentanoate at 1atm. Molecular beam mass spectrometry was used with tunable synchrotron vacuum ultraviolet (VUV) pho- toionization for low pressure flames of both methyl pentanoate and methyl hex- anoate, and soft electron-impact ionization was used for atmospheric pressure flames of methyl pentanoate. Mole fraction profiles of stable and intermediate species, as well as temperature profiles, were measured in the flames. A detailed chemical kinetic high temperature reaction mechanism for small alkyl ester oxi- dation was extended to include combustion of methyl pentanoate and methyl hex- anoate, and the resulting model was used to compare computed values with ex- perimentally measured values. Reaction pathways for both fuels were identified, with good agreement between measured and computed species profiles. Implica- tions of these results for future studies of larger alkyl ester fuels are discussed. Keywords: Spectroscopy, Reaction Kinetics. DOI 10.1515/zpch-2014-0596 Received August 29, 2014; accepted December 15, 2014 || Dedicated to Professor Henning Bockhorn on the occasion of his 70th birthday *Corresponding author: Charles K. Westbrook, Lawrence Livermore National Laboratory, Livermore, CA, USA, e-mail: [email protected] Oleg P. Korobeinichev, Ilya E. -
Supplemental Material
Haddad Supp pp 1 Supplementary materials for: Global features of neural activity in the olfactory system form a parallel code that predicts olfactory behavior and perception Rafi Haddad1,2#, Tali Weiss1, Rehan Khan1σ, Boaz Nadler2, Nathalie Mandairon3, 3 1* 1*# Moustafa Bensafi , Elad Schneidman and Noam Sobel . Section 1: PCA analysis We provide a step by step example of how we conducted the PCA analysis. Assume we have 8 odors, each located on the vertexes of a 3 dimensional unit cube. Each odor can thus be represented by the exact binary code of the numbers 0 to 7. We can represent these odors in the following binary code matrix: Odor ID Pattern code: 1 0 0 0 2 0 0 1 3 0 1 0 4 0 1 1 5 1 0 0 6 1 0 1 7 1 1 0 8 1 1 1 1 Haddad Supp pp 2 Using any available mathematical tool (we used Matlab 'princomp' method) we can calculate the principle components scores of this matrix. In this case the values of the PC1 scores are: [1 0 0]. The PC1 projection value of each row is the projection of each row by the PC1 weight vector. For example the PC1 value of the first row is [0,0,0]X[1,0,0] = 0X1 + 0X0 + 0X0 = 0. (this is a vector multiplication). Thus the PC1 value of each row of this matrix is: 0,0,0,0,1,1,1,1. Note that usually the PC1 is calculated on a centered matrix (the columns of the matrix have zero mean) and thus the PC1 value might be shifted by some value. -
GC-MS) Techniques and Selected Ion Flow Tube Mass Spectrometry (SIFT-MS) Assessment of Volatiles Produced from Nitric Oxide Producing Smart Dressings
The detection of trace volatiles from complex matrices using gas chromatography mass spectrometry (GC-MS) techniques and selected ion flow tube mass spectrometry (SIFT-MS) assessment of volatiles produced from nitric oxide producing smart dressings Oliver John Gould A thesis submitted in partial fulfilment of the requirements of the University of the West of England, Bristol for the degree of Doctor of Philosophy Faculty of Health and Applied Sciences, University of the West of England, Bristol 2019 Copyright declaration This copy has been supplied on the understanding that it is copyright material and that no quotation from the thesis may be published without proper acknowledgment. i Acknowledgements I would like to thank my supervisors Professor Norman Ratcliffe, and Associate Professor Ben de Lacy Costello for all their help, guidance, and support over the course of this work, and for their co-authorship on the published versions of chapters 2 and 3. I would also like to thank Dr Hugh Munro and Edixomed Ltd for financial support and scientific guidance with chapter 4. I would like to thank my co-authors on the publication of chapter 2 Tom Wieczorek, Professor Raj Persad. Also thank you to my co-authors on the publication of chapter 3, Amy Smart, Dr Angus Macmaster, and Dr Karen Ransley; and express my appreciation to Givaudan for funding the work undertaken in chapter 3. Thank you also to my colleagues and fellow post graduate research students at the University of the West of England for always being on hand for discussion and generation of ideas. A special mention to Dr Peter Jones who has been mentoring me on mass spectrometry for a number of years. -
South African Journal of Enology and Viticulture
SOUTH AFRICAN JOURNAL OF ENOLOGY AND VITICULTURE ISSN NR 0253-939X VOLUME FORTY ONE· NUMBER TWO 41(2) 2020 LATEST IMPACT FACTOR: 1.833 MANUSCRIPTS ARE PUBLISHED ONLINE BY SUNJournals (http://www.journals.ac.za/index.php/sajev) Electronic copies of manuscripts are freely available at: http://www.sasev.org and on the internet via most search engines EDITOR Prof Leon M.T. Dicks E-mail: [email protected] ASSISTANT-EDITORS Dr Pia Addison (South Africa), Dr Elleunorah Allsopp (South Africa), Dr Rolene Bauer (South Africa), Prof Florian Bauer (South Africa), Dr Astrid Buica (South Africa), Prof Simone Castellarin (Canada), Dr Michael Costello (USA), Prof Benoit Divol (South Africa), Prof Maret du Toit (South Africa), Dr Ana M Fortes (Portugal), Dr Francois Halleen (South Africa), Dr Carolyn Howell (South Africa), Dr Lucilla Iacumin (Italy), Dr Neil Jolly (South Africa), Dr Sandra Lamprecht (South Africa), Dr Marianne McKay (South Africa), Dr John Moore (South Africa), Dr Lizel Mostert (South Africa), Dr Carlos Poblete-Echeverria (South Africa), Prof Doris Rauhut (Germany), Dr Evodia Setati (South Africa), Prof Giuseppe Spano (Italy), Janene Strydom (South Africa), Hanlé Theron (South Africa), Dr Philip Young (South Africa) Subscription for subscribers in South Africa = R850.00 (as from January 2021) Subscription for subscribers from outside South Africa = R2 100.00 (as from January 2021) Payment: Remittances to the correct amount must accompany all orders. Customers outside South Africa should preferably remit by bank drafts. Bank drafts must be calculated in, or for conversion into, South African Currency, free of all charges, and be made payable to SAWWV.