Search Results
Results 1 - 50 of 1946
1 2 3 4 5 6 7 8 9 10 >
Li Xinxiu X School of Pharmaceutical Sciences, Shandong University, Jinan, - - 2014
Soybean protein hydrolysates (SPHs), especially oligopeptides, have shown a variety of functional properties, including immunomodulatory and anti-oxidant effects. Soybean protein hydrolysate products have been used as functional ingredients in food, sports nutrition or clinical nutrition. However, the mixture is mostly undefined due to its complex nature, containing peptides and minor ...
Brent Lacey Cluff - - 2014
The structural composition of PM2.5 monitored in the atmosphere is usually divided by the analysis of organic carbon, black (also called elemental) carbon, and inorganic salts. The characterization of the chemical composition of aerosols represents a significant challenge to analysts and studies are frequently limited to determination of aerosol bulk ...
Barbaro Elena E Department of Environmental Sciences, Informatics and Statistics, University of Venice, Ca' Foscari, Calle Larga Santa Marta 2137, 30123, Venice, Italy, - - 2014
Amino acids represent a fraction of organic matter in marine and freshwater ecosystems, and a source of carbon, nitrogen and energy. L-Amino acids are the most common enantiomers in nature because these chiral forms are used during the biosynthesis of proteins and peptide. To the contrary, the occurrence of D-amino ...
Sadhukhan Sushabhan - - 2014
Herein we report a study combining metabolomics and mass isotopomer analysis used for investigation of the biochemical fate of γ-hydroxybutyric acid (GHB). Using various 13C incorporation labeling patterns into GHB, we have discovered that GHB is catabolized by previously unknown processes that include (i) direct β-oxidation to acetyl-CoA and glycolate; ...
Kim Yong-Hyun - - 2014
Headspace (HS) analysis has been recommended as one of the most optimal methods for extracting and analyzing volatile organic compounds from samples in diverse media such as soil and water. Short-chain volatile fatty acids (VFA, C3 - C7) with strong adsorptivity were selected as the target compounds to assess the ...
Liu Dong-Ze DZ Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, P. R. China. - - 2014
Phytochemical investigation of the AcOEt extract of G. Lucidum has led to the isolation of two new triterpenoids, 1 and 2, together with five known ones, 3-7. The structures of the new compounds were identified as 12β-acetoxy-3β,7β-dihydroxy-11,15,23-trioxolanost-8-en-26-oic acid butyl ester (1) and 12β-acetoxy-3,7,11,15,23-pentaoxolanost-8-en-26-oic acid butyl ester (2) on the basis ...
Kang Bo-Sik BS School of Life Science and Biotechnology, Korea Univ, 5-1, Anam-dong, Sungbuk-gu, Seoul 136-701, Republic of - - 2014
In Korean rice wine (makgeolli) model, we tried to develop a prediction model capable of eliciting a quantitative relationship between initial amino acids in makgeolli mash and major aromatic compounds, such as fusel alcohols, their acetate esters, and ethyl esters of fatty acids, in makgeolli brewed. Mass-spectrometry-based electronic nose (MS-EN) ...
West Charles E CE Petroleum and Environmental Geochemistry Group, Biogeochemistry Research Centre, Plymouth University, Drake Circus, Plymouth, PL4 8AA, - - 2014
The identification of key acid metabolites ('signature' metabolites) has allowed significant improvements to be made in our understanding of the biodegradation of petroleum hydrocarbons, in reservoir and in contaminated natural systems, such as aquifers and seawater. On this basis, anaerobic oxidation is now more widely accepted as one viable mechanism, ...
Guo Mengzhe M Department of Chemistry, Zhejiang University, Zheda road 38#, Hangzhou, 310027, - - 2014
The fragmentation of b3 ions derived from protonated Arg-Xxx-Asp-Ala-Ala (Xxx = Ala, Asp, Glu, Cys) and Arg-Xxx-Glu-Ala-Ala was investigated by electrospray ionization tandem mass spectrometry (MS (n) ) with collision-induced dissociation. A particular ion, which is 1 Da less than b2 ion, is shown to be the c2-H2O ion. The mechanism for its ...
Li Lixin L College of Chemistry and Environmental Science, Hebei University, Key Laboratory of Analytical Science and Technology of Hebei Province, Baoding 071002, China; Hebei Chemical & Pharmaceutical College, Shijiazhuang 050026, - - 2014
The degradation of penicillin G, penicillin V, and ampicillin in milk in the presence of β-lactamase was investigated by ultra-performance liquid chromatography coupled with electrospray ionization-time-of-flight mass spectrometry. Degradation products of the 3 penicillins in milk were identified based on the fact that the metabolites or degradation products contain a ...
Guerra Paula Vanessa - - 2014
Flavanol related structures such as epicatechin and catechins have been associated with potential antioxidant activity in food and are known to interfere with the Maillard reaction through scavenging of reactive dicarbonyl compounds. High resolution ESI-TOF mass spectrometry and isotope labeling technique were used to assess the reactivity of glycine with ...
Jobelius Carsten C Water Chemistry, Engler-Bunte-Institut, Karlsruhe Institute of Technology (KIT), 76131, Karlsruhe, - - 2014
The anaerobic microbial degradation of aromatic and heterocyclic compounds is a prevalent process in contaminated groundwater systems. The introduction of functional groups into the contaminant molecules often results in aromatic and heterocyclic and succinic acids. These metabolites can be used as indicators for prevailing degradation processes. Therefore, there is a ...
Sekimoto Kanako K Graduate School of Nanobioscience, Yokohama City University, 22-2 Seto, Kanazawa-ku, Yokohama, Kanagawa, 236-0027 Japan. - - 2014
The positive and negative ionization characteristics of 20 different α-amino acids were investigated using Direct Analysis in Real Time (DART) mass spectrometry. Almost all of the amino acids M were ionized to generate the (de)protonated analytes [M ± H](±)via proton transfer reactions with the typical background ions H3O(+)(H2O)n and O2˙(-) ...
Kahnt Ariane - - 2014
An oxygenated MW 188 compound is commonly observed in substantial abundance in atmospheric aerosol samples and was proposed in previous studies as an α-pinene-related marker compound which is associated with ageing processes. Owing to difficulties to produce this compound in sufficient amounts in laboratory studies and the occurrence of isobaric ...
Abedin Md Zainul MZ a Food Biopolymer Research Group, Food Technology Division, School of Industrial Technology, Universiti Sains Malaysia , 11800 Penang , - - 2014
The molecular mass distribution, amino acid composition and radical-scavenging activity of collagen hydrolysates prepared from collagen isolated from the sea cucumber Stichopus vastus were investigated. β and α1 chains of the collagen were successfully hydrolysed by trypsin. The molecular mass distribution of the hydrolysates ranged from 5 to 25 kDa, and ...
Ruan Y Y a Department of Traditional Chinese Medicine , College of Agronomy, Henan Agricultural University , Zhengzhou 450002 , P.R. - - 2014
Biotransformation of grandiflorenic acid by permeabilised fungus Fusarium graminearum to yield its hydroxylation derivative, 12α-hydroxygrandiflorenic acid, was studied. The biotransformed product was isolated by column chromatography and its structure was determined by mass spectrum and nuclear magnetic resonance analysis. Grandiflorenic acid was efficiently metabolised by the fungus. After 72 h, the ...
Murad André M AM Embrapa Genetic Resources and Biotechnology, Laboratory of Synthetic Biology, Parque Estação Biológica, PqEB, Av. W5 Norte, 70770-917, Brasília, DF, - - 2014
Improving the quality and performance of soybean oil as biodiesel depends on the chemical composition of its fatty acids and requires an increase in monounsaturated acids and a reduction in polyunsaturated acids. Despite its current use as a source of biofuel, soybean oil contains an average of 25 % oleic acid ...
Hsu Fong-Fu FF Mass Spectrometry Resource, Division of Endocrinology, Diabetes, Metabolism and Lipid Research, - - 2014
The structures of phosphatidylethanolamine (PE) in Leishmania infantum are unique in that they consist of a rare cyclopropane fatty acid (CFA) containing PE subfamily, including CFA-containing plasmalogen PE species. In this contribution, we applied multiple-stage linear ion-trap combined with high-resolution mass spectrometry to define the structures of PEs that were ...
Yu Xiaomin X Department of Microbiology, University of Illinois at Urbana-Champaign, Urbana, Illinois, - - 2014
Two related actinomycetes, Glycomyces sp. strain NRRL B-16210 and Stackebrandtia nassauensis NRRL B-16338, were identified as potential phosphonic acid producers by screening for the gene encoding phosphoenolpyruvate (PEP) mutase, which is required for the biosynthesis of most phosphonates. Using a variety of analytical techniques, both strains were subsequently shown to ...
Zimmermann Michael M Institute of Molecular Systems Biology, ETH Zurich , Zurich 8093, - - 2014
Mass spectrometry has been established as a powerful and versatile technique for studying cellular metabolism. Applications range from profiling of metabolites to accurate quantification and tracing of stable isotopes through the biochemical reaction network. Despite broad coverage of central carbon metabolism, most methods fail to provide accurate assessments of the ...
Wohlfarth Ariane A Chemistry and Drug Metabolism, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, 251 Bayview Boulevard, Baltimore, MD, 21224, - - 2014
PB-22 (1-pentyl-8-quinolinyl ester-1H-indole-3-carboxylic acid) and 5F-PB-22 (1-(5-fluoropentyl)-8-quinolinyl ester-1H-indole-3-carboxylic acid) are new synthetic cannabinoids with a quinoline substructure and the first marketed substances with an ester bond linkage. No human metabolism data are currently available, making it difficult to document PB-22 and 5F-PB-22 intake from urine analysis, and complicating assessment of ...
Khodadoust S S a Medicinal Plants Research Center, Yasuj University of Medical Science , Yasuj , - - 2014
This article reports the fatty acid composition of the oil extracts from Quercus brantii fruits growing in Kohgiloye va Boyer Ahmad province in southwestern Iran. The oil from Q. brantii fruits was extracted with hexane in Soxhlet apparatus and subsequently identified and determined by using gas chromatography-mass spectroscopy. The results ...
Müller Karsten K a Chemistry Department , University of Marburg , Marburg , - - 2014
A method for the deuterium labelling of fluorobenzoic acids (FBAs) via acidic H/D exchange of the aromatic hydrogen atoms in concentrated D2SO4 is described. The synthesis is shown to be easy, fast, low-priced and without the use of catalysts or further purification. The use of at least double-deuterated FBAs as ...
Chiominto Alessandra A INAIL Research, Department of Occupational Hygiene, via Fontana Candida, 1-00040 Monteporzio Catone (RM), - - 2014
The most commonly analytical method used for the assessment of the occupational exposure to airborne endotoxins is the LAL test, but other methods are reported in the literature. The objective of this work was to develop and validate a method using HPLC coupled to triple quadrupole mass spectrometer for the ...
Mohammed Magdy M D MM a Laboratory of Molecular Biology of Infectious Agents , Graduate School of Biomedical Sciences, School of Pharmaceutical Sciences, Nagasaki University , Nagasaki , - - 2014
One new dihydrochalcone diglycoside has been isolated from the EtOAc fraction of the Egyptian seagrass Thalassodendrin ciliatum (Forsk.) den Hartog, and was identified as 6'-O-rhamnosyl-(1‴ → 6″)-glucopyranosyl asebogenin for which a trivial name Thalassodendrone was established. Furthermore, five known phenolics were isolated and identified as asebotin, quercetin 3,7-diglucoside, protocatechuic acid, ferulic acid ...
Cocuron Jean-Christophe JC Department of Molecular Genetics, The Ohio State University, Columbus, OH 43210, - - 2014
Physaria fendleri (syn. lesquerella), is a Brassicaceae producing lesquerolic acid, a highly-valued hydroxy fatty acid that could be used for several industrial applications, such as cosmetics, lubricating greases, paints, plastics, and biofuels. Free of toxins, physaria is an attractive alternative to imported castor (Ricinus communis) oil, and is hence on ...
Cioni Joel P JP Department of Microbiology and ‡The Institute for Genomic Biology, University of Illinois , Urbana-Champaign, Illinois 61801, United - - 2014
Streptomyces regensis strain WC-3744 was identified as a potential phosphonic acid producer in a large-scale screen of microorganisms for the presence of the pepM gene, which encodes the key phosphonate biosynthetic enzyme phosphoenolpyruvate phosphonomutase. (31)P NMR revealed the presence of several unidentified phosphonates in spent medium after growth of S. ...
Bouchoux Guy G Département de Chimie, Laboratoire des Mécanismes Réactionnels, Ecole Polytechnique, 91120, Palaiseau, - - 2014
This article constitutes the fourth part of a general review of the gas-phase protonation thermochemistry of polyfunctional molecules (Part 1: Theory and methods, Mass Spectrom Rev 2007, 26:775-835, Part 2: Saturated basic sites, Mass Spectrom Rev 2012, 31:353-390, Part 3: Amino acids, Mass Spectrom Rev 2012, 31:391-435). This fourth part ...
Teixeira António A Center for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB), Quinta de Prados, Vila Real 5001-801, Portugal. - - 2014
The characterization of the metabolites accumulated in the grapes of specific cultivars grown in different climates is of particular importance for viticulturists and enologists. In the present study, the metabolite profiling of grapes from the cultivars, Alvarinho, Arinto and Padeiro de Basto, of two Portuguese Controlled Denomination of Origin (DOC) ...
Liesenfeld Andrea A University of Bonn, Kekulé-Institute of Organic Chemistry and Biochemistry, Gerhard-Domagk-Str.1, D-53121 Bonn, - - 2014
Two new 9,9'-spirobifluorene-derived crown ethers were prepared and used to recognise constitutionally isomeric amino acid derivatives. The performance of the receptors was evaluated by ESI-mass spectrometry using the isomer labelled guest method (ILGM). This method revealed the preferred binding of L-norleucine and L-leucine compared to L-isoleucine for both receptors. Furthermore, ...
Bilton Penelope A PA Institute of Fundamental Sciences, Massey University, Palmerston North, New - - 2014
Negative-ion electrospray mass spectra of samples of naphthenic acids contain peaks due to monomeric species [M-H](-) and dimeric species [2M-H](-). Working with a model system, intensities of the dimers were related to the intensities of monomers through linear inverse modelling. The statistical approaches investigated and the details of their applications ...
Lee Sunmin S a Department of Bioscience and Biotechnology , Konkuk University , Seoul , Republic of - - 2014
This study aimed to investigate the biotransformation of soybean isoflavones to hydroxyisoflavones, and the primary and secondary metabolite change during Aspergillus oryzae KACC40247-mediated fermentation by gas chromatography-time of flight-mass spectrometry and LC-MS with multivariate analysis. The mass spectrometric analysis revealed that acetylglycosides and glycosides decreased during the first 12 h of ...
Wright Cynthia R CR a Department of Chemistry , University of Alabama in Huntsville , Huntsville , AL 35899 , - - 2013
The essential oils from the cladodes of Opuntia littoralis, Opuntia ficus-indica and Opuntia prolifera growing wild on Santa Catalina Island, California, were obtained by hydrodistillation and analysed by gas chromatography-mass spectrometry (GC-MS). Terpenoids were the dominant class of volatiles in O. littoralis, with the two main components being the furanoid ...
Cegłowski Michał M Faculty of Chemistry, Adam Mickiewicz University in Poznan, Umultowska 89b, 61-614, Poznan, - - 2013
Carbon nanotubes (CNTs) have been ascertained to constitute versatile assisting matrices for laser desorption/ionization mass spectrometric analysis of different molecules. The functionalization thereof can lead to obtaining laser desorption/ionization assisting surfaces that would allow the detection of molecules at lower concentration and produce spectra with a better signal-to-noise ratio. Pristine, ...
Cordeiro Nereida N Competence Centre in Exact Science and Engineering and ‡Competence Centre of Life Sciences, University of Madeira , 9000-390 Funchal, - - 2013
The lipophilic extracts from the storage root of 13 cultivars of sweet potato ( Ipomoea batatas (L.) Lam.) were evaluated by gas chromatography-mass spectrometry with the aim to valorize them and offer information on their nutritional properties and potential health benefits. The amount of lipophilic extractives ranged from 0.87 to ...
Kajita Ryo - - 2013
Various kinds of aldehyde-mediated chemical modifications of proteins have been identified as being exclusively covalent. We report a unique noncovalent modification: the aldehyde-mediated epimerization of the N-terminal amino acid. Epimerization of amino acids is thought to cause conformational changes that alter their biological activity. However, few mechanistic studies have been ...
Ramírez-Gonzáilez Irama I Instituto de Investigaciones, Facultad de Farmacia y Bioanálisis, Universidad de Los Andes, Mérida. - - 2013
From the aerial parts of Hypericum laricifolium Juss., twelve compounds were isolated and identified. They were the xanthones: 1-hydroxy-7-methoxy-xanthone (1), 1,7-dihydroxy-xanthone (2), 2-hydroxy-xanthone (3), 6-deoxyisojacareubin (4), 1,3-dihydroxy-6-methoxy-xanthone (6), and 1,5,6-trihydroxy-7-methoxy-xanthone (7), together with beta-sitosterol, betulinic acid, vanillic acid, isoquercitrin and a mixture of quercetin and isorhamnetin. All the compounds were ...
Wang Wen-Lian - - 2013
Two new 20α-ursane-type triterpenoids (1-2) were isolated from the roots of Ilex cornuta, along with three known triterpenoids (3-5). The structures of compounds 1-2 were determined as 3β, 23-dihydroxy-20α(H)-urs-12-en-28-oic acid (1), 3β,19α,23-trihydroxy-20α(H)-urs-12-en-28-oic acid 3β-O-α-l-arabinopyranoside (2), on the basis of hydrolysis and spectral evidence, including 1D- and 2D-NMR and high-resolution electrospray ...
Araujo Pedro - - 2013
The content of triacylglycerols (TAG) in krill oil is generally omitted from the labels of commercial supplements and unacknowledged in studies aimed at proving its health benefits. The present study demonstrates that TAG compounds, in addition to phospholipids and lysophospholipids, are an important lipid class in pure krill oil. The ...
Cheng Chun-Ru - - 2013
The metabolism of traditional Chinese medicine is very complicated and has been a great challenge. In the present paper, a new strategy was established to study the metabolism of crude extract from Ganoderma lucidum using the highly separative and sensitive ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry. Based on the investigation ...
Carillo Sara S Dipartimento di Scienze Chimiche, Università di Napoli Federico II, Complesso Universitario di Monte S.Angelo, Via Cintia 4, 80126 Napoli, - - 2013
Cyanobacteria are aquatic and photosynthetic microorganisms, which contribute up to 30% of the yearly oxygen production on the earth. They have the distinction of being the oldest known fossils, more than 3.5 billion years old, and are one of the largest and most important groups of bacteria on earth. Cyanobacteria ...
Haupa Karolina - - 2013
Aminosulfonic acids are structurally related to amino acids as bifunctional compounds. Some of them like taurine and homotaurine play important roles in biology. Although there is a vast literature devoted to the electrospray ionization mass spectrometric (ESI-MS) study of amino acid aggregation, no such study has been performed so far ...
Ragonese Carla - - 2014
In this work the characterisation of the lipid fraction of several species of marine macro algae gathered along the eastern coast of Sicily is reported. Two species of green marine algae (Chloropyceae), two species of red marine algae (Rhodophyceae) and four species of brown marine algae (Pheophyceae) were evaluated in ...
Yao Xin - - 2013
Ginkgo biloba leaf extract has been widely used in dietary supplements and more recently in some foods and beverages. In addition to the well-known flavonol glycosides and terpene lactones, G. biloba leaves are also rich in amino acids. To determine the content of free amino acids, a reliable method has ...
Hammann Simon - - 2013
Fatty acids of microalgae have been studied as potential chemotaxonomic markers, to reveal plausible lipid phycotoxins or in the context of mass production of algal biofuels. The planctonic microalgae Alexandrium tamarense (Dinophyceae) is a common harmful algal bloom species that often proliferates in eutrophic costal waters. Alexandrium blooms are the ...
Teramoto Kanae - - 2013
Mycolic acids have been used as important chemotaxonomic markers. In this study, a newly developed matrix-assisted laser desorption/ionization time-of-flight mass spectrometer with a spiral ion trajectory (MALDI spiral-TOFMS) was applied to the characterization of mycolic acids of three type strains of validated species belonging to the genus Dietzia (D. papillomatosis ...
Ramos Patricia A B - - 2013
Lipophilic extracts of Cynara cardunculus L. var. altilis (DC) from south of Portugal (Baixo Alentejo) were studied by gas chromatography-mass spectrometry. One sesquiterpene lactone, four pentacyclic triterpenes and five sterols were reported for the first time as cultivated cardoon components, namely deacylcynaropicrin, β- and α-amyrin, lupenyl and ψ-taraxasteryl acetates, stigmasterol,, ...
Kim Nam Sook - - 2014
In this study, a method for discriminating natural mozzarella cheese from cheese substitutes, using fatty acid profiles, phytosterol contents, and statistical comparison, was developed. A total of 27 cheeses were evaluated: eight natural mozzarella cheeses (NMCs), four imitation mozzarella cheeses (IMCs), 12 processed cheeses (PCs) and three mixed cheeses (MCs) ...
Liu Xinping - - 2013
A highly sensitive, specific and robust method for the analysis of oxidized metabolites of linoleic, acid (LA), arachidonic acid (AA) and docosahexaenoic acid (DHA) was developed using charge-switch derivatization, LC-ESI MS/MS with selected reaction monitoring (SRM) and quantitation by high mass accuracy analysis of product ions thereby minimizing interferences from ...
Abu-Reidah I M - - 2013
Lettuce (Lactuca sativa), a leafy vegetal widely consumed worldwide, fresh cut or minimally processed, constitutes a major dietary source of natural antioxidants and bioactive compounds. In this study, reversed-phase ultra-high-performance liquid chromatography (RP-UHPLC) coupled to electrospray ionization-quadrupole-time-of-flight mass spectrometry (ESI-QTOF-MS) was applied for the comprehensive profiling of polar and semi-polar ...
1 2 3 4 5 6 7 8 9 10 >