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Larabi Cherif - - 2013
Transformation of lignocellulosic biomass to biofuels involves multiple processes, in which thermal decomposition, hydrotreatment are the most central steps. Current work focuses on the impact of several solid acids and Keggin-type heteropolyacids on the decomposition temperature (Td) of pine wood and the characterization of the resulted products. It has been ...
Rezanka Tomáš - - 2013
LC with atmospheric pressure chemical ionization (APCI) MS with reversed and chiral phases was used for separation of triacylglycerols (TAGs) from yeasts of the genera Candida, Kluyveromyces, Rhodotorula, Saccharomyces, Torulospora, Trichosporon and Yarrowia. Chiral LC-APCI-MS is based on using two columns in series packed with a 3,5-dimethylphenyl carbamate modified β-cyclodextrin ...
Kasmaei K Mogodiniyai - - 2013
A meta-analysis was conducted to establish linkages between crop and fermentation variables. Data from well-controlled mini silage studies were used in which no additives had been used and no ingress of air had occurred. The silage set consisted of data on crop chemical composition and epiphytic lactic acid bacteria count, ...
Malá Zdena - - 2013
The subject of this work is the definition of a simple model based on general isotachophoresis (ITP) theory that allows describing and predicting the behavior of ITP systems compatible with electrospray-ionization mass-spectrometric (ESI-MS) detection. The model is exemplified by anionic ITP of weak acids which represent an interesting potential application ...
Hu Xiuting - - 2013
The aim of this study was to examine the interaction between amylose and 1-butanol during the 1-butanol-hydrochloric acid (1-butanol-HCl) hydrolysis of normal rice starch. The interaction model between amylose and 1-butanol was proposed using gas chromatography-mass spectrometry (GC-MS), (13)C cross polarization and magic angle spinning NMR analysis ((13)C CP/MAS NMR), ...
Hamia Chahrazed - - 2013
The essential oil obtained by hydrodistillation of the flowers of Rhanterium adpressum Coss. & Durieu was analyzed using GC and GC-MS. The essential oil was very rich in monoterpene compounds. The major components identified were the monoterpene hydrocarbons: camphene (21.8%), myrcene (19.3%) and alpha-pinene (17.4%). Other compounds, including limonene, beta-pinene ...
Bai Rong - - 2013
In this study, two new compounds and six known compounds were isolated from the aerial parts of Pteris semipinnata. The chemical structures of these two new compounds were elucidated as 6β,11α-dihydroxy-15-oxo-ent-kaur-16-en-19-oic acid (1) and 7α,11α-dihydroxy-15-oxo-ent-kaur-16-en-19-oic acid (2) by the extensive spectral methods including 2D NMR and HR-MS techniques.
Shao Yafang - - 2014
This study investigated differences in total phenolic content (TPC), antioxidant capacity, and phenolic acids in free, conjugated and bound fractions of white (unpolished), red and black rice at 1-, 2-, and 3-weeks of grain development after flowering and at maturity. Unlike the TPC (mg/100g) of white rice (14.6-33.4) and red ...
Du Hui - - 2013
Mugua, fruit of the genus Chaenomeles, is a valuable source of health food and Chinese medicine. To elucidate the bioactive compounds of five wild Chaenomeles species, extracts from fresh fruits were investigated by HPLC-DAD/ESI-MS/MS. Among the 24 polyphenol compounds obtained, 20 were flavan-3-ols (including catechin, epicatechin and procyanidin oligomers). The ...
Sekikawa Akira - - 2013
Few previous studies have reported the association of aortic stiffness with marine n-3 fatty acids (Fas) in the general population. The aim of this study was to determine the combined and independent associations of 2 major marine n-3 FAs, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), with aortic stiffness evaluated ...
Falavigna Claudia - - 2013
Fumonisin derivatives obtained by esterification of fumonisin B1 (FB1) with palmitic, oleic and linoleic fatty acids have been recently described, but never reported in raw maize so far. In this study, the presence of oleoyl-EFB1 (EFB1OA) and linoleoyl-EFB1 (EFB1LA) in raw maize is reported by means of a suitable LC-ESI-MS/MS ...
Deepak M M Drug Standardisation Division, Centre for Medicinal Plants Research, Arya Vaidya Sala, Kottakkal, Malappuram, Kerala, - - 2013
Grahaṇimihira tailam is an unexplored ayurvedic oil preparation which consists of 34 ingredients. The efficacy of this traditional ayurvedic medicine is undisputable. Proper clinical standardization of this formulation will go a long way in securing greater recognition for it. The main objective of this study was to develop standardization parameters ...
Zangrando Roberta - - 2013
Biomass burning is one of the most important sources of organic matter in the atmosphere as it affects the absorption and scattering of solar radiation, creates cloud condensation nuclei and possibly influences ice and snow albedo. Here we created and validated an analytical method using HPLC/(-)-ESI-MS/MS to determine phenolic compounds ...
Cao Bei - - 2013
Oxidative stress is involved in the pathogenesis of multiple system atrophy (MSA). Uric acid has an antioxidative effect. Our aim is to clarify the correlations between serum uric acid and MSA in Chinese population. A total of 234 patients with probable MSA and 240 age- and gender- matched healthy controls ...
Cardoso Anajás S - - 2013
To investigate the association between serum uric acid concentration according to the presence or absence of non-alcoholic fatty liver disease (NAFLD) and/or metabolic syndrome (MS) in overweight or obese children and adolescents. This was a cross-sectional study conducted from April of 2009 to March of 2010, including 129 children and ...
Ceunen Stijn - - 2013
The rare Mexican species Stevia phlebophylla A. Gray was long considered to be the only known Stevia species, beside the well-known S. rebaudiana, containing the highly sweet diterpenoid steviol glycosides. We report a re-evaluation of this claim after phytochemically screening leaves obtained from two herbarium specimens of S. phlebophylla for ...
Vanzo Andreja - - 2013
Apple quality was investigated in the scab-resistant 'Liberty', 'Santana' and 'Topaz' cultivars and the scab-susceptible 'Golden Delicious' cultivar. Trees subjected to the same crop load were cultivated using either an organic (ORG) or an integrated production (IP) system. Physicochemical properties, phenolic content and sensorial quality of fruit from both systems ...
Takada Kentaro - - 2013
Surugamides A- E (1-5), cyclic octapeptides with four D-amino acid residues, were isolated from the broth of marine-derived Streptomyces sp. Their planar structures were determined by analyses of spectroscopic data, and the absolute configuration of constituent amino acid residues was determined by the Marfey's method. Differentiation of D-Ile and L-Ile ...
Xu Yong-Jiang - - 2013
Background: The main objective of this study was to explore the potential use of electron ionization (EI) and chemical ionization (CI) techniques in fatty acid measurement. MS/MS, together with main fragment ions in EI and positive CI of 37 fatty acid methyl esters (FAMEs), were investigated using a triple quadrupole ...
Black Brenna A - - 2013
Lactobacillus hammesii converts linoleic acid into an antifungal hydroxy fatty acid. High speed counter-current chromatography (HSCCC) using a hexane/ethyl acetate/methanol/water solvent system [3.5:1.5:3:2 (v/v/v/v)] allowed isolation of the antifungal hydroxy fatty acid. A method was developed for characterization of antifungal hydroxy fatty acids using normal phase liquid chromatography combined with ...
Menon Rani - - 2013
The macronutrient and micronutrient compositions of traditional media used to cultivate Lactic Acid Bacteria are largely undefined, which precludes their use in many metabolic bioassays. In order to address this deficiency, we developed MS: a carbohydrate-supplemental semidefined medium with low-background coloration. MS was designed to support the semiselective cultivation of ...
Niu Wei - - 2013
We have utilized in vitro evolution to identify tRNA variants with significantly enhanced activity for the incorporation of unnatural amino acids into proteins in response to a quadruplet codon in both bacterial and mammalian cells. This approach will facilitate the creation of an optimized and standardized system for the genetic ...
Rose Christopher M CM Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53706, United - - 2013
Metabolic labeling of cells using heavy amino acids is most commonly used for relative quantitation; however, partner mass shifts also detail the number of heavy amino acids contained within the precursor species. Here, we use a recently developed metabolic labeling technique, NeuCode (neutron encoding) stable isotope labeling with amino acids ...
Liu Kaiying - - 2013
Capillary array electrophoresis (CAE) is a promising technique for multiple enantiomeric separations. Carboxytetramethylrhodamine succinimidyl ester (TAMRA SE), a rhodamine-core fluorescent probe, has rarely been applied as an original precolumn derivatization reagent for chiral amino acid (AA) analysis so far. For these purposes, high-throughput enantiomeric separations of 12 TAMRA SE-AAs by ...
Hallmann Ewelina - - 2013
A specific objective of this paper was to evaluate seasonal changes in bioactive compounds level (carotenoids and polyphenols) in juice prepared from organic and non-organic tomatoes in Poland. In the examined tomato juice, the content of dry matter, vitamin C, carotenoids as well as polyphenols (by HPLC method) has been ...
Guenther G G - - 2013
Nutrient stress that produces quiescence and catabolism in normal cells is lethal to cancer cells, because oncogenic mutations constitutively drive anabolism. One driver of biosynthesis in cancer cells is the mammalian target of rapamycin complex 1 (mTORC1) signaling complex. Activating mTORC1 by deleting its negative regulator tuberous sclerosis complex 2 ...
Bach Vibe - - 2013
Jerusalem artichoke tubers (Helianthus tuberosus L.) undergo enzymatic browning when peeled or cut, and turn grey after boiling, due to after-cooking darkening reactions between iron and phenolic acids. In an attempt to reveal the components responsible for these discolouration reactions, sensory evaluation and instrumental colour measurements were related to contents ...
Wang Ling-Fei - - 2013
In this study, citric acid production from extract of Jerusalem artichoke tubers by the genetically engineered yeast Yarrowia lipolytica strain 30 was investigated. After the compositions of the extract of Jerusalem artichoke tubers for citric acid production were optimized, the results showed that natural components of extract of Jerusalem artichoke ...
Wang Lifang - - 2013
Boronic acids are important in the organic and biological arenas. Thus, their identification and characterization are important. ESI-MS is a well-known tool for such uses. Herein we report a systematic analysis of the chemical behavior of arylboronic acids under ESI-MS conditions. Such information will be very critical to understanding the ...
Mochizuki Yuko - - 2013
A novel bromoquinolinium reagent, i.e., 1-(3-aminopropyl)-3-bromoquinolinium bromide (APBQ), was synthesized for the analysis of carboxylic acids. A simple and practical pre-column derivatization procedure using the APBQ in reversed-phase chromatography and mass spectrometry (HPLC-MS) has been developed using bile acids and free fatty acids, as the representative carboxylic acids in biological ...
Tong Shengqiang - - 2013
This work concentrates on extending the utilization of multiple dual mode counter-current chromatography in chiral separations. Two aromatic acids, 2-(6-methoxy-2-naphthyl) propionic acid and 2-phenylpropionic acid, were enantioseparated by multiple dual mode counter-current chromatography using hydroxypropyl-β-cyclodextrin as chiral selector. The two-phase solvent systems consisting of n-hexane-ethyl acetate-0.1 mol L(-1) phosphate buffer ...
Bhatia Anil - - 2013
Withania somnifera (L.) Dunal (Solanaceae), commonly known as Ashwagandha, is one of the most valued Indian medicinal plant with several pharmaceutical and nutraceutical applications. Metabolic profiling was performed by GC-MS and NMR spectroscopy on the fruits obtained from four chemotypes of W. somnifera. A combination of (1)H NMR spectroscopy and ...
Tani Yasushi - - 2013
Glycosphingolipids (GSLs) are essential membrane components of eukaryotic cells. Recently, a new type of fungal neogala-series GSL was identified in aureobasidin A-resistant fungi. In this study, we analyzed GSLs from four pathogenic fungal strains belonging to the order Hypocreales, and found that Mariannaea elegans contained both acidic GSLs and neutral ...
Fayek Nesrin M - - 2013
β-amyrin-3-(3'-dimethyl) butyrate, a new natural compound was isolated from the fruits of Manilkara zapota (L.) Van Royen, in addition to lupeol-3-acetate and 4-caffeoylquinic acid (cryptochlorogenic acid). The structures of these compounds were identified using different spectral methods (IR, MS, UV, (1)H-NMR, (13)C-NMR and 2D-NMR). The alcoholic and aqueous extracts of ...
Isobe Kimiyasu - - 2013
Teratosphaeria acidotherma AIU BGA-1 isolated from an acidic and high temperature hot spring produced four intracellular β-d-galactosidases with different pH activity profiles, in which three forms were acidophilic and stable from extremely acidic to neutral pH region. The other one was alkalophilic and unstable in the acidic pH region.
Nagao Ryuji - - 2013
This paper reports the synthesis and the application of novel derivatization reagents possessing a pyridylthiourea structure for the enantiospecific determination of chiral amines and carboxylic acids in high-throughput LC-ESI-MS/MS. The novel reagents, i.e., (R)-N-(3-pyridylthiocarbamoyl)pyrrolidine-2-carboxylic acid (PyT-C) and (S)-3-amino-1-(3-pyridylthiocarbamoyl)pyrrolidine (PyT-N), were evaluated as chiral derivatization reagents for the enantiomeric determination of ...
Hou Aiqin - - 2013
Aqueous solutions of 3,3',4,4'-benzophenone tetracarboxylic dianhydride (BPTCD) were successfully employed in treatment of cotton fabrics to bring multiple functions onto the cotton cellulose. The overall reaction mechanism of the chemical finishing process was investigated. Results revealed that the dianhydride groups of BPTCD were hydrolyzed to tetracarboxylic acid groups, and the ...
Zhang Luxin - - 2013
With the aim to develop an ecologically viable catalytic pathway for furfural production without the use of inorganic acids, H3PW12O40, Amberlyst-5 and NKC-9 (macroporous styrene-based sulfonic acid resin) were used as catalysts for producing furfural from xylose, xylan and lignocellulosic biomass in [BMIM]Cl under microwave irradiation at atmospheric pressure. A ...
Ehrnhoefer-Ressler Miriam M - - 2013
Drinking or gargling Salvia officinalis L. infusion (sage infusion) is thought to soothe a sore throat, tonsillitis, and inflamed, red gums, although structure-based scientific evidence for the key anti-inflammatory compounds in sage infusion is scarce. Human gingival fibroblasts (HGF-1) were treated with sage infusion (SI) or SI fractions containing either ...
Mai Franziska - - 2013
Enzymatic browning is generally reported as the reaction between phenolic substances and enzymes. The quality of iceberg lettuce is directly linked to this discoloration. In particular, the color change of lettuce stems considerably reduces consumer acceptance and thus decreases sales revenue of iceberg lettuce. Ten phenolic compounds (caffeic acid, chlorogenic ...
Gao Jian-Bo - - 2013
A new tetracyclic triterpenoid compound named as mastichinoic acid A (1) was isolated from Mastich. The structure was established as 3,7-dioxo-11β-hydroxy-5α-tirucalla-8,24(Z)-dien-26-oic acid by various spectroscopic techniques including MS, 1D, and 2D NMR and HRTOFMS.
Parrot Delphine - - 2013
A chemical study of the lichen Ramalina siliquosa complex found in Brittany was conducted. Eight chemotypes were considered and their chemical composition was elucidated for the first time by LC-MS analysis. Ten main compounds were identified: conhypoprotocetraric acid (1), salazinic acid (2), peristictic acid (3), cryptostictic acid (4), protocetraric acid ...
Levison Bruce S - - 2013
Oxidized fatty acids formed via lipid peroxidation are implicated in pathological processes such as inflammation and atherosclerosis. A number of methods may be used to detect specific oxidized fatty acids containing a single or multiple combinations of epoxide, hydroxyl, ketone and hydroperoxide moieties on varying carbon chain lengths from C8 ...
Izumikawa Miho - - 2013
As part of our chemical screening program for new microbial secondary metabolites, we discovered a new compound, JBIR-107 (1), from the culture of Streptomyces tateyamensis NBRC 105047 isolated from a marine sponge sample. Extensive NMR and MS spectroscopic data enabled the structure of 1 to be determined as 5-acetamido-6-(4-(methyl(2-oxo-3-phenylpropyl)amino)phenyl)-4-oxohexanoic acid.
Grant-Preece Paris - - 2013
The efficiency of different white wine antioxidant systems in preventing aldehyde production from amino acids by oxidative processes is not well understood. The aim of this study was to assess the efficiency of sulphur dioxide alone and in combination with either glutathione, ascorbic acid or its stereoisomer erythorbic acid, in ...
Khalili Mohammad - - 2013
OBJECTIVES: Multiple sclerosis is a neurodegenerative and demyelinating disease of central nervous system. High levels of oxidative stress are associated with inflammation and play an important role in pathogenesis of multiple sclerosis. This double-blind, randomized controlled clinical study was carried out to determine the effect of daily consumption of lipoic ...
Zhao Yunliang - - 2013
In-situ measurements of organic compounds in both gas and particle phases were made with a Thermal desorption Aerosol Gas chromatograph (TAG) instrument. The gas/particle partitioning of phthalic acid, pinonaldehyde and 6, 10, 14-trimethyl-2-pentadecanone is discussed in detail to explore secondary organic aerosol (SOA) formation mechanisms. Measured fractions in the particle ...
Zhang Li - - 2013
Tobacco leaves obtained from different geographical regions in China were profiled using gas chromatography-mass spectrometry (GC-MS) coupled with multivariate data analyses. Hierarchical cluster analysis (HCA) and principal component analysis (PCA) showed that the tobacco metabolome was clearly dependent on geographical origins; climatic conditions, such as temperature, precipitation, and temperature, imposed ...
Ma Xin X Department of Chemistry and Biochemistry, The University of Arizona, Tucson, AZ 85721, - - 2013
Glu, Gln, Pro, and Ala are the main amino acids involved in ammonia detoxification in mosquitoes. In order to develop a tandem mass spectrometry method (MS(2)) to monitor each carbon of the above isotopically-labeled (13)C-amino acids for metabolic studies, the compositions and origins of atoms in fragments of the protonated ...
Kodani Shinya - - 2013
A new polyacetylene carboxylic acid named montiporic acid D (1) was isolated along with a known polyacetylene alcohol, (Z)-13,15-hexadecadien-2,4-diyn-1-ol (2) from scleractinian coral Montipora digitata. The structures of compounds were determined by analyses of NMR and MS spectra.
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