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Zeng Xu X School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China. - - 2014
We report here a theoretical study with quantum chemical calculations based on experimental results to understand highly efficient reduction of CO2 to formic acid by using zinc under hydrothermal conditions. Results showed that zinc hydride (Zn-H) is a key intermediate species in the reduction of CO2 to formic acid, which ...
Savourey Solène S CEA, IRAMIS, NIMBE, CNRS UMR 3299, 91191 Gif-sur-Yvette (France) - - 2014
The disproportionation of formic acid to methanol was unveiled in 2013 using iridium catalysts. Although attractive, this transformation suffers from very low yields; methanol was produced in less than 2 % yield, because the competitive dehydrogenation of formic acid (to CO2 and H2 ) is favored. We report herein the efficient ...
Felluga Fulvia F Dipartimento di Scienze Chimiche e Farmaceutiche, Università degli Studi di Trieste, Trieste, - - 2014
Enantiomerically enriched isoparaconic acid derivatives were obtained by kinetic enzymatic resolution. To explain the solvent dependence observed for their optical rotatory power a computational investigation of their chiroptical properties was performed. Chirality 00:000-000, 2014. © 2014 Wiley Periodicals, Inc.
Pópity-Tóth Eva E Department of Physical Chemistry and Materials Science, University of Szeged, Aradi vértanúk tere 1., Szeged H-6720, - - 2014
Horizontally propagating chemical fronts leading to the formation of a single stable convection roll are investigated in the iodate-arsenous acid reaction with arsenous acid stoichiometrically limiting, leaving the surface active iodine present in the product mixture. In sufficiently thin solution layers with open upper surface, the contribution of Marangoni instability ...
Brock Nelson L NL Institut für Organische Chemie, Hagenring 30, 38106 Braunschweig, Germany. - - 2014
Dimethylsulfoniopropionate (DMSP) is a versatile sulfur source for the production of sulfur-containing secondary metabolites by marine bacteria from the Roseobacter clade. (34)S-labelled DMSP and cysteine, and several DMSP derivatives with modified S-alkyl groups were synthesised and used in feeding experiments that gave insights into the biosynthesis of sulfur volatiles from ...
Palenik Mark C MC Theoretical and Computational Biomolecular Physics Group, Department of Physics and Astronomy, Purdue University, West Lafayette, IN 47907, USA. - - 2014
Understanding mechanisms of (+)-anti-BPDE detoxification is crucial for combating its mutagenic and potent carcinogenic action. However, energetic-structural correlations of reaction intermediates and transition states during detoxification via hydrolysis are poorly understood. To gain mechanistic insight we have computationally characterized intermediate and transition species associated with spontaneous and general-acid catalyzed hydrolysis ...
Polanco Carlos C Facultad de Ciencias de la Salud, Universidad Anáhuac, Col. Lomas Anáhuac C.P. 52786 Huixquilucan Estado de México, - - 2014
In accordance with the second law of thermodynamics, the Universe as a whole tends to higher entropy. However, the sequence of far-from-equilibrium events that led to the emergence of life on Earth could have imposed order and complexity during the course of chemical reactions in the so-called primordial soup of ...
Martí-Centelles Vicente V Departamento de Química Inorgánica y Orgánica, Universitat Jaume I, Av. Sos Baynat, s/n, E-12071 Castellón (Spain), Fax: - - 2014
Pseudopeptidic receptors containing an acridine unit have been prepared and their fluorescence response to a series of amino acids was measured in water. Free amino acids, not protected either at the C or the N terminus, were used for this purpose. The prepared receptors display a selective response to tryptophan ...
Dorofeeva Olga V - - 2014
Accurate gas-phase enthalpies of formation of 20 common α-amino acids, 7 uncommon amino acids, and 3 small peptides were calculated by combining G4 theory calculations with an isodesmic reaction approach. The internal consistency over a set of Hf(g) values was achieved by sequential adjustment of their values through the isodesmic ...
Volker Alexandra R AR Roy J. Carver Dept of Biochemistry, Biophysics and Molecular Biology, Iowa State University, - - 2014
Escherichia coli was engineered for the production of even and odd-chain fatty acids (FA) by fermentation. Co-production of thiolase, hydroxybutyryl-CoA dehydrogenase, crotonase and trans-enoyl-CoA reductase from a synthetic operon allowed the production of butyrate, hexanoate, and octanoate. Elimination of native fermentation pathways by genetic deletion (ΔldhA, ΔadhE, ΔackA, Δpta, ΔfrdC) ...
Venkatakrishnan Harish H School of Civil and Environmental Engineering, Nanyang Technological University, 639798, Singapore; Advanced Environmental Biotechnology Center, Nanyang Environment and Water Research Institute, Nanyang Technological University, 637141, Singapore. Electronic address: - - 2014
A high strength chemical industry wastewater was assessed for its impact on anaerobic microbial community dynamics and consequently mesophilic methane generation. Cumulative methane production was 251 mL/g total chemical oxygen demand removed at standard temperature and pressure at the end of 30 days experimental period with a highest recorded methane ...
Davalos Juan Zenon - - 2014
Carborane clusters are not found in Nature and are exclusively man-made. In this work we study, both experimentally and computationally, the gas-phase acidity (measured GA = 1325 kJ•mol-1, computed GA = 1321 kJ•mol-1) and liquid-phase acidity (measured pKa = 2.00, computed pKa = 1.88) of the carborane acid closo-1-COOH-1,7-C2B10H11. The ...
Kitadai Norio N Earth-Life Science Institute, Tokyo Institute of Technology, 2-12-1-IE-1 Ookayama, Meguro-ku, Tokyo, 152-8550, Japan, - - 2014
Prediction of the thermodynamic behaviors of biomolecules at high temperature and pressure is fundamental to understanding the role of hydrothermal systems in the origin and evolution of life on the primitive Earth. However, available thermodynamic dataset for amino acids, essential components for life, cannot represent experimentally observed polymerization behaviors of ...
Campillo Tony T Université de Lyon, F-69622, Lyon, - - 2014
The soil and rhizosphere inhabiting bacterium Agrobacterium fabrum (genomospecies G8 of the A. tumefaciens species complex) is known to have species-specific genes involved in ferulic acid degradation. Here, we characterized by genetic and analytical means intermediates of degradation as feruloyl-CoA, 4-hydroxy-3-methoxyphenyl-β-hydroxypropionyl-CoA, 4-hydroxy-3-methoxyphenyl-β-ketopropionyl-CoA, vanillic acid and protocatechuic acid. Genes atu1416, atu1417 ...
Dong Meiting M College of Chemistry and Life Science, Zhejiang Normal University, Jinhua, 321004, Zhejiang, People's Republic of - - 2014
Here we report a facile one-pot method for the preparation of high-quality CdSe nanocrystals (NCs) in aqueous solution under an air atmosphere. Compared with the traditional use of NaHSe or H2 Se, the more stable sodium selenite is utilized as the Se source for preparing highly luminescent CdSe nanocrystals. By ...
Anand Richa R Division of Applied Sciences and Indo-Russian Centre for Biotechnology, Indian Institute of Information Technology, Allahabad, 211012, Uttar Pradesh, - - 2014
The present work investigates the anti-inflammatory activity of alpha-linolenic acid (ALA) and linoleic acid (LA) using computational and experimental analysis. The binding affinity of ALA and LA was appraised for cyclooxygenase 1 (COX-1), cyclooxygenase 2 (COX-2), and 5-lipoxygenase (5-LOX) using AutoDock 4.2 and AutoDock Vina 1.1.2. Anti-inflammatory activity of ALA ...
Bedogni Gabriel Alejandro GA Departamento de Ciencias Básicas y Aplicadas, Universidad Nacional del Chaco Austral, Cdte. Fernández 755, Pcia, 3700, Roque Sáenz Peña, Chaco, - - 2014
This work describes theoretical and experimental studies on glycerol esterification to obtain acetins focusing on the obtained isomers. The reaction of glycerol with acetic acid was carried out on Amberlyst 36 wet. Density functional theory calculations on the level of M06-2X functional and 6-311+G(d,p) basis set are carried out and ...
Sjöberg Béatrice B Laboratoire Chrono-Environnement, UMR CNRS 6249, Université de Franche-Comté, 16 route de Gray, 25030 Besançon cedex, - - 2014
The Raman spectra of a series of tripeptides with the basic formula GlyAAGly where the central amino acid (AA) was tryptophan, tyrosine, phenylalanine, glycine, methionine, histidine, lysine and leucine were measured in H2O. The theoretical Raman spectra obtained using density functional theory (DFT) calculations at the B3LYP/6-311+G(2df,2pd) level of theory ...
Jiménez-Osés Gonzalo - - 2014
In recent years, our group has reported the highly diastereoselective acid-catalyzed N,O-acetalization/intramolecular transcarbamoylation cascade of reactions between protected α-amino acid derivatives (Ser and Thr) and tetramethoxyalkanes. The resulting oligocyclic N,O-acetals have been used as excellent chiral building blocks for asymmetric transformations such as diastereoselective alkylation of the α-position. We now ...
Ivanov B N BN Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow Region, 142290, Russia. - - 2014
Experimental data concerning the role of ascorbic acid in both the maintenance of photosynthesis and in the protection of the photosynthetic apparatus against reactive oxygen species and photoinhibition are reviewed. The function of ascorbic acid as an electron donor in the "Krasnovsky reaction", as well as its physiological role as ...
Prasad Saurav S Department of Biotechnology, Indian Institute of Technology, Guwahati, Guwahati, Assam, 781039, India, - - 2014
Casein whey permeate (CWP), a lactose-enriched dairy waste effluent, is a viable feed stock for the production of value-added products. Two lactic acid bacteria were cultivated in a synthetic casein whey permeate medium with or without pH control. Lactobacillus lactis ATCC 4797 produced D-lactic acid (DLA) at 12.5 g l(-1) in a ...
Sałaga M M Department of Biomolecular Chemistry, Faculty of Medicine, Medical University of Lodz, Lodz, - - 2014
Pharmacological treatment and/or maintenance of remission in inflammatory bowel diseases (IBD) is currently one of the biggest challenge in the field of gastroenterology. Available therapies are mostly limited to overcoming the symptoms, but not the cause of the disease. Recently, the endocannabinoid system has been proposed as a novel target ...
Bagi Péter P Department of Organic Chemistry and Technology, Budapest University of Technology and Economics, Budapest, - - 2014
The resolution methods applying (-)-(4R,5R)-4,5-bis(diphenylhydroxymethyl)-2,2-dimethyldioxolane ("TADDOL"), (-)-(2R,3R)-α,α,α',α'-tetraphenyl-1,4-dioxaspiro[4.5]decan-2,3-dimethanol ("spiro-TADDOL"), as well as the acidic and neutral Ca(2+) salts of (-)-O,O'-dibenzoyl- and (-)-O,O'-di-p-toluoyl-(2R,3R)-tartaric acid were extended for the preparation of 1-n-butyl-3-methyl-3-phospholene 1-oxide in optically active form. In one case, the intermediate diastereomeric complex could be identified by single-crystal X-ray analysis. The absolute ...
Bian Jing J Beijing Key Laboratory of Lignocellulosic Chemistry, College of Materials Science and Technology, Beijing Forestry University, Beijing 100083, - - 2014
Hemicelluloses from sugarcane bagasse were subjected to microwave-assisted acid hydrolysis at mild temperature to produce xylooligosaccharides (XOS). The hydrolysis was performed with dilute H2SO4 at 90°C and the influence of acid concentration (0.1-0.3M) and reaction time (20-40min) on the XOS production was ascertained with response surface methodology based on central ...
Barua Priyanka P a Department of Chemistry , Gauhati University , Guwahati 781014 , Assam , - - 2014
A total of nine oilseeds with more than 15 wt% oil have been investigated for evaluating them as feedstock for biodiesel industries. Fatty acid profiles of all the nine oil samples have been determined by GC-MS analysis. The saponification numbers, gross heats of combustion of the oils and those of corresponding ...
Shibakami Motonari M Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Central 6th, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8566, Japan. Electronic address: - - 2014
We experimentally demonstrated that paramylon, a storage polysaccharide of Euglena gracilis, is efficiently thermoplasticized by adding acyl groups that differ in alkyl chain length. Glass transition temperature of mixed paramylon esters was higher than those of plant-based polylactic acid (PLA), poly 11-aminoundecanoic acid (PA11), and petroleum-based acrylonitrile-butadiene-styrene (ABS) resin and ...
Ochoa-Terán Adrián A Centro de Graduados e Investigación, Instituto Tecnológico de Tijuana, 22510 Tijuana, BC, - - 2014
A regioselective synthesis has been developed for the preparation of a series of N,N'-disubstituted 4,4'-carbonylbis(carbamoylbenzoic) acids and N,N'-disubstituted bis(carbamoyl) terephthalic acids by treatment of 3,3',4,4'-benzophenonetetracarboxylic dianhydride (1) and 1,2,4,5-benzenetetracarboxylic dianhydride (2) with arylalkyl primary amines (A-N). The carbamoylcarboxylic acid derivatives were synthesized with good yield and high purity. The specific ...
Ciunel Krzysztof K Gdańsk University of Technology, 80-233 Gdatisk, 1 1/12 Narutowicza Str., Gdańsk, Poland. - - 2014
Rapeseed pellet - crushed seed residue from oil extraction is a by-product of fatty acid methyl esters production process. As other types of biomass, it can either be burned directly in furnaces or processed to increase its energetic value. Biomass is renewable, abundant and has domestic usage; the sources ofbiomass ...
Kowałczyk Iwona - - 2014
3-(3-Dimethylammonio)propylammonio propanoate bromide (1), 4-(3-dimethylammonio)propylammonio butanoate bromide (2), and 5-(3-dimethylammonio)propylammonio pentanoate bromide (3) have been obtained in reaction of 1,1-dimethyl-1,3-propylenediamine with 3-bromopropionic acid, ethyl 4-bromobutyrate and 5-bromovaleric acid, respectively. The products have been characterized by FTIR, Raman and NMR spectroscopy. Also B3LYP calculations have been carried out. The screening constants ...
Hosoda Kazufumi K Institute for Academic Initiatives, Osaka University, Suita, Osaka, - - 2014
Chloroplasts originated from cyanobacteria through endosymbiosis. The original cyanobacterial endosymbiont evolved to adapt to the biochemically rich intracellular environment of the host cell while maintaining its photosynthetic function; however, no such process has been experimentally demonstrated. Here, we show the adaptation of a model cyanobacterium, Synechocystis sp. PCC 6803, to ...
Rayung Marwah M Department of Chemistry, Faculty of Science, Universiti Putra Malaysia, Serdang 43400, Malaysia. - - 2014
In this work, biodegradable composites from poly(lactic acid) (PLA) and oil palm empty fruit bunch (OPEFB) fiber were prepared by melt blending method. Prior to mixing, the fiber was modified through bleaching treatment using hydrogen peroxide. Bleached fiber composite showed an improvement in mechanical properties as compared to untreated fiber ...
Dubey Ritesh - - 2013
The acid-pyridine heterosynthon may be used as a "molecular" module to probe the structural landscape of the benzoic acid : isonicotinamide 1 : 1 cocrystal, BA : INA. Experimental structures of 1 : 1 cocrystals of fluorobenzoic acids (FBA) with isonicotinamide (INA) contain this heterosynthon and correspond to high-energy structures of 1 : 1 BA : INA.
El Razak Ahmed Abd - - 2013
Water samples from three different environments including Mid Atlantic Ridge, Red Sea and Mediterranean Sea were screened in order to isolate new polyunsaturated fatty acids (PUFAs) bacterial producers especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Two hundred and fifty-one isolates were screened for PUFA production and among them the ...
McMahon Matthew D - - 2013
Short-chain fatty acid (SCFAs) biosynthesis is pertinent to production of biofuels, industrial compounds, and pharmaceuticals from renewable resources. To expand on Escherichia coli SCFA products, we previously implemented a coenzyme A (CoA)-dependent pathway that condenses acetyl-CoA to a diverse group of short-chain fatty acyl-CoAs. To increase product titers and reduce ...
Settimo Luca - - 2013
Assessment of the accuracy of experimental and theoretical methods of pKa determination for acids and bases as separate classes. Four literature pKa datasets were checked for errors and pKa values assigned unambiguously to a single acidic and/or basic ionisation centre. A new chemically diverse and drug-like dataset was compiled from ...
Malovrh Tomaž - - 2013
The aim of the current study was to determine the incorporation of cis (c) 9, trans (t) 11-conjugated linoleic acid (CLA) and t10, c12-CLA into porcine erythrocytes-both isomers were supplemented in equal proportions. The study group consisted of 16 piglets randomly assigned into experimental and control group. For the period ...
Rai Pankaj K - - 2013
Hydrogen production from sugarcane bagasse (SCB) by integrating dark-fermentation by Enterobacter aerogenes MTCC 2822 and photo-fermentation by Rhodopseudomonas BHU 01 was investigated. The SCB was hydrolysed by sulphuric acid and the hydrolysate detoxified by passing through adsorbent resin column (Amberlite XAD-4) to remove the inhibitory furfural, and subjected to dark-fermentation. ...
Kumar Rajaram Shyam - - 2013
In this study, a hybrid system of response surface methodology followed by genetic algorithm has been adopted to optimize the production medium for L-glutamic acid fermentation with mixed cultures of Corynebacterium glutamicum and Pseudomonas reptilovora. The optimal combination of media components for maximal production of L-glutamic acid was found to ...
Li Xiangrong - - 2013
Ascorbic acid, α-tocopherol and proanthocyanidins are three classic dietary antioxidants. In this study, the interaction between the three antioxidants and human serum albumin (HSA) was investigated by several spectroscopic techniques. Experimental results proved that the three antioxidants quench the fluorescence of HSA through a static (proanthocyanidins) or static-dynamic combined quenching ...
Alvarez-Diduk Ruslán - - 2013
Four flavonols namely: quercetin, morin, kaempferol and myricetin were studied using spectrophotometry UV/Vis, in aqueous solution. The study was performed varying the pH to analyze the stability of these compounds, and to estimate their acidity constants. In addition, the deprotonation mechanisms were studied using computational chemistry, within the Density Functional ...
Nishio Yousuke - - 2013
Understand the process of amino acid fermentation as a comprehensive system is a challenging task. Previously, we developed a literature-based dynamic simulation model, which included transcriptional regulation, transcription, translation, and enzymatic reactions related to glycolysis, the pentose phosphate pathway, the tricarboxylic acid (TCA) cycle, and the anaplerotic pathway of Escherichia ...
Tomuţă Ioan - - 2013
Abstract The paper proposes a near infrared method able to directly and simultaneously quantify ascorbic acid and sodium ascorbate in powder blends for tableting and in vitamin C chewable tablets without any sample preparation. In the first step, calibration models for the quantification of ascorbic acid and sodium ascorbate in ...
Slivkin A I - - 2013
We studied the effects of an analogue of isonicotinic acid hydrazide on the treatment course of experimental tuberculosis. Complex analysis has demonstrated the efficiency of isonicotinic acid hydrazide immobilized on a carrier that consisted of water-soluble cation-active analogue of chitosan (N-chlorohydroxypropyl chitosan) in a complex with cobalt ions in the ...
Nishino Hideo - - 2013
The delivery of extraterrestrial organics to primitive Earth is considered to have triggered the origin and subsequent evolution of life. Indeed, enantiomerically enriched amino acids of nonterrestrial origin have been found in carbonaceous meteorites, and enantioselective photodecomposition by circularly polarized light (CPL) in outer space has been proposed to have ...
Sanyano Naruetsawan - - 2013
Harvesting of marine Chlorella sp. by autoflocculation and flocculation by addition of coagulant with pH adjustment was investigated in this study. Autoflocculation provided low efficiency. Response surface methodology was employed to optimize the coagulant dosage and pH for flocculation. Aluminium sulfate and ferric chloride were investigated coagulants. The empirical models ...
Pitre Spencer P - - 2013
The photocatalytic hydroxylation of boronic acids with methylene blue as photosensitizer proceeds with high efficiency. Detailed time-resolved studies of the relevant rate constants provide a clear mechanistic understanding of excited state processes and guided the selection of the photocatalyst and the optimization of experimental conditions.
Grayson Matthew Neil - - 2013
1,1'-Bi-2-naphthol (BINOL)-derived catalysts catalyze the asymmetric propargylation of ketones. Density functional theory (DFT) calculations show that the reaction proceeds via a closed six-membered transition structure (TS) in which the chiral catalyst undergoes an exchange process with the original cyclic boronate ligand. This leads to a Lewis acid type activation mode, ...
Liu Liu - - 2013
Spectator or actor? Density functional theory calculations were performed to examine the role of the base in the nickel-catalyzed cross-coupling of aryl phosphates with arylboronic acids. Potassium phosphate was found to not act as a spectator base but was involved in the transmetalation step, as shown by a lower barrier ...
Krügel Undine - - 2013
Plant sucrose transporters (SUTs) are functional as sucrose-proton-cotransporters with an optimal transport activity in the acidic pH range. Recently, the pH optimum of the Solanum tuberosum sucrose transporter StSUT1 was experimentally determined to range at an unexpectedly low pH of 3 or even below. Various research groups have confirmed these ...
Xing Huabin - - 2014
Long chain unsaturated fatty acids (LCUFAs) are important food components and dietary supplements due to their beneficial health effects. The key process to produce high-purity LCUFAs is to separate long chain fatty acids (LCFAs) with different degrees of unsaturation and chain lengths. This process faces great challenge because of similar ...
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