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Geisler Anne C - - 2011
Redox-sensitive posttranslational modification emerged as important signaling mechanisms. Besides other posttranslational modifications nitroalkylation by nitrated fatty acids mediate favorable anti-inflammatory effects. This review gives an overview of the generation and the reactivity of nitrated fatty acids. Additionally, it provides insights into the so far described pathways regulated by nitrated fatty ...
Herter Susanne - - 2011
Phenylalkanes are ubiquitously found in nature as pollutants originating from oil, gas oil and petrol. Rising commercial demand for mineral oil fractions has led to the increased prevalence of environmental contamination, whereby these particular hydrocarbons are encountered by bacteria which have subsequently developed sophisticated metabolic routes for purposes of degradation. ...
Bian Wenjuan - - 2011
Degradation of 4-chlorophenol by pulsed high voltage discharge is an intricate process involving a series of complex chemical reactions. Hydroxylation of 4-chlorophenol to form hydroquinone, 4-chlororesorcinol and 4-chlorocatechol is the first step, though a very small amount of direct cleavage products of the C(1)-C(2) or C(5)-C(6) bond are observed. The ...
Neal Colin - - 2011
Dissolved aluminium concentrations ([Al]) in the <0.45μm filtered fraction are described for 54 UK river sites covering rural, acidic/acid sensitive, agricultural and urban typologies, and wide pH range (4 to 11). High [Al] occurred under acidic conditions and for acid runoff neutralised by bicarbonate rich groundwater. Thermodynamic analysis indicates Al ...
Ohshima Takashi - - 2011
A direct catalytic substitution of various allylic and benzylic alcohols with synthetically useful, but acid-sensitive Boc, Bus, and Dios protected amine nucleophiles, which have not been well utilized for Lewis acid catalysis, with various functionalities (OTBS, OTHP, etc.) was efficiently catalyzed by 1 mol% of Au(iii) under mild conditions.
Souza Lismery Pereira - - 2011
A direct determination of gallic acid was achieved at a carbon paste electrode modified with carbon nanotubes under differential pulse voltammetry conditions. The values obtained for gallic acid were used to estimate the antioxidant properties of sample wine based on gallic acid oxidation. The proposed method is based on gallic ...
Ling Siew Chen - - 2011
Aims:  Polyhydroxyalkanoate (PHA) with enhanced physicochemical properties will be ideal for a wide range of practical applications. The incorporation of 3-hydroxy-4-methylvalerate (3H4MV) into the polymer backbone is known to improve the overall properties of the resulting polymer. However, the most suitable microorganism and PHA synthase that can synthesize this monomer ...
Hakala Risto A - - 2011
Biodegradable poly(ester anhydride) networks based on linear and star-shaped poly(ε-caprolactone) based precursors were synthesized with the aim of obtaining matrixes suitable for release of macromolecular active agents. The ring-opening polymerization yielded hydroxyl telechelic oligomers, which were end-functionalized with succinic anhydride or with alkenylsuccinic anhydrides containing 8, 12, or 18 carbons ...
Kayi Hakan - - 2011
We have theoretically investigated the low energy conformers of neutral glycine (NH(2)CH(2)COOH) and its isomer methylcarbamic acid (CH(3)NHCOOH) in the gas phase. A total of 16 different levels of the theory, including CCSD(T), MP2 and B3LYP methods with various Pople and Dunning type basis sets with and without polarization and ...
Degenhardt Dani - - 2011
In the present study, an ephemeral (E) and a semi-permanent (SP) wetland were divided into halves using a polyvinyl curtain and one half of each wetland was treated with dicamba (3,6-dichloro-o-anisic acid), bromoxynil (3,5-dibromo-4-hydroxy-benzonitrile), MCPA [(4-chloro-2-methylphenoxy)acetic acid], 2,4-D [(2,4-dichlorophenoxy)acetic acid], mecoprop [RS- and (R)-2-(4-chloro-o-tolyloxy)propionic acid] and dichlorprop [(RS)-2-(2,4-dichlorophenoxy)propionic acid] such ...
Bettaieb Iness - - 2011
BACKGROUND: Cumin (Cuminum cyminum L.) seeds of two geographic origins, Tunisia (TCS) and India (ICS), were studied regarding their fatty acid and essential oil composition. RESULTS: Oil yields were 17.77 and 15.40% for TCS and ICS respectively. Petroselinic acid (C18:1n-12) was the major fatty acid in both varieties, with a ...
Notario Rafael - - 2011
Calorimetric measurements are expected to provide useful data regarding the relative stability of α- versus β-amino acid isomers, which in turn may help understand why Nature chose α- instead of β-amino acids for the formation of the biomolecules that are essential constituents of life on Earth. The present study is ...
Arivazhagan G - - 2011
FTIR and 13C NMR spectral studies have been carried out on diisopropyl ether-propionic acid binary mixture to probe the molecular interactions and stoichiometry of complexation. Density functional theory (DFT) calculations of vibrational frequencies of pure acid and ether-acid binary mixtures have also been performed. In addition, Kirkwood-correlation factors, excess permittivity ...
You Sheng-Jie - - 2011
Sludge in a sequential batch reactor (SBR) system was used to investigate the effect of lead toxicity on metabolisms of polyphosphate accumulating organisms (PAOs) and glycogen accumulating organisms (GAOs) communities fed with acetic acid or glucose as their sole carbon source, respectively. Results showed that the effect of lead on ...
Sa Jeong-Hoon - - 2011
The motivation for this work was the potential of hydrophobic amino acids such as glycine, l-alanine, and l-valine to be applied as thermodynamic hydrate inhibitors (THIs). To confirm their capabilities in inhibiting the formation of gas hydrates, three-phase (liquid-hydrate-vapor) equilibrium conditions for carbon dioxide hydrate formation in the presence of ...
Liang Xiao - - 2011
The acid-catalyzed hydrolysis of dimethyl ether (DME) to methanol was examined using ab initio density functional metadynamics simulations. Diffusion of the acid proton from the aqueous medium, leading to the formation of a protonated DME, is 12.3 kcal mol(-1) activated and 9.3 kcal mol(-1) endothermic, indicating a greater affinity of ...
Lee Phil Ho - - 2011
Trifluoromethanesulfonic acid catalyzed isomerization of kinetic enol derivatives to the thermodynamically favored isomers was developed. Under the present conditions, kinetic enol phosphates, enol acetates and benzoates, and enol sulfonates were smoothly isomerized to produce the corresponding thermodynamically favored isomers in good to excellent yields.
Bhat Krishna L - - 2011
Boroxines are the six-membered cyclotrimeric dehydration products of organoboronic acids, 3R–B(OH)2 → R3B3O3 + 3H2O, and in recent years have emerged as a useful class of organoboron molecules with applications in organic synthesis both as reagents and catalysts, as structural components in boronic-acid-derived pharmaceutical agents, and as anion acceptors and ...
Bickler Stephen W - - 2011
Environmental enteropathy has been identified as a cause of poor growth in children living in low-income countries, but a mechanism has not been well defined. We suggest changes in sulfur amino acid metabolism can in part explain the poor growth and possibly the histological changes in the small bowel, which ...
Valentincic T - - 2011
On the basis of previous findings of behavioural discrimination of amino acids and on the knowledge of electrophysiology of the catfish (genera Ictalurus and Ameiurus) olfactory organs, behavioural experiments that investigated olfactory discrimination of amino acid mixtures were carried out on the black bullhead Ameiurus melas. Repeated presentations of food-rewarded ...
Besset Céline J - - 2011
Strategies for the preparation of polycarbonates, derived from natural polyhydroxy monomeric repeat units, were developed for biosourced polycarbonates based on quinic acid. The design and synthesis of regioselectively tert-butyldimethylsilyloxy (TBS)-protected 1,4- and 1,5-diol monomers of quinic acid were followed by optimization of their copolymerizations with phosgene, generated in situ from ...
Lluch Cristina - - 2011
Fast-degrading linear and branched polyanhydrides are obtained by melt-condensation of novel di- and tri-carboxylic acid monomers based on oleic and undecylenic acid synthesized using photoinitiated thiol-ene click chemistry. (1) H NMR spectroscopy, size exclusion chromatography, differential scanning calorimetry, thermogravimetric analysis, and FT-IR spectroscopy have been used to fully characterize these ...
Ottosson Niklas - - 2011
We report highly surface sensitive core-level photoelectron spectra of small carboxylic acids (formic, acetic and butyric acid) and their respective carboxylate conjugate base forms (formate, acetate and butyrate) in aqueous solution. The relative surface propensity of the carboxylic acids and carboxylates is obtained by monitoring their respective C1s signal intensities ...
Jimenez Ana I - - 2011
The natural non-proteinogenic α-amino acid 1-aminocyclopropanecarboxylic acid (Ac3c) has been vaporized by laser ablation and studied in the gas phase by molecular-beam Fourier transform microwave spectroscopy. Comparison of the experimental rotational and 14N nuclear quadrupole coupling constants with the values predicted ab initio for these parameters has allowed the unambiguous ...
Kocharova N A - - 2011
An acidic O-polysaccharide was isolated by mild acid degradation of the lipopolysaccharide of Providencia alcalifaciens O25 followed by gel-permeation and anion-exchange chromatography. The O-polysaccharide was studied by sugar and methylation analyses along with (1)H and (13)C NMR spectroscopy, including two-dimensional correlation (1)H,(13)C HMBC, and (1)H,(1)H ROESY experiments both in D2O ...
Petäjä Tuukka - - 2011
Sulfuric acid is a key compound in atmospheric nucleation. Here we report on the observation of a close-to-collision-limited sulfuric acid dimer formation in atmospherically relevant laboratory conditions in the absence of measurable quantities of ammonia or organics. The observed dimer formation rate was clearly higher than the measured new particle ...
Mayworm Marco A S - - 2011
Contents of proteins, carbohydrates and oil of seeds of 57 individuals of Vochysiaceae, involving one species of Callisthene, six of Qualea, one of Salvertia and eight of Vochysia were determined. The main nutritional reserves of Vochysiaceae seeds are proteins (20% in average) and oils (21. 6%). Mean of carbohydrate contents ...
Kim Seyun - - 2011
Comment on: Kim S, et al. Cell Metab 2011; 13:215-21.
An Guijie - - 2011
A link tooth wheel-cylinder non-thermal plasma reactor was set up to investigate the degradation of phenol in the mists. In addition, the decomposition efficiency of phenol, TOC removal, and byproduct formation were investigated. The stable discharge was achieved in both air and the mist condition. The decomposition efficiency and TOC ...
Liu Feng - - 2011
A mutant termed Aeromonas hydrophila AKLF was constructed by deleting acetic acid pathway related genes pta and ackA in A. hydrophila 4AK4. Accumulation of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) in A. hydrophila AKLF was increased by 47% from 2.11 to 3.10g/L associated with a reduction on acetic acid formation compared with A. hydrophila ...
Kapinos Larisa E - - 2011
Adenosine (Ado) can accept three protons, at N1, N3, and N7, to give H(3) (Ado)(3+) , and thus has three macro acidity constants. Unfortunately, these constants do not reflect the real basicity of the N sites due to internal repulsions, for example, between (N1)H(+) and (N7)H(+) . However, these macroconstants ...
Pini Cecilia - - 2011
In Pseudomonas putida, as in many other eubacteria, cyclopropane fatty acids (CFAs) accumulate in the membrane during the stationary phase of growth. We show here that cfaB gene expression in P. putida KT2440 is dependent on the RpoS sigma factor that recognizes the sequence 5'-CTACTCT-3' between -8 and -14. We ...
Petersen Tue B - - 2011
An efficient arylation of carboxylic acids with diaryliodonium salts has been developed, giving aryl esters in high yields within short reaction times for both aromatic and aliphatic substrates. The transition-metal-free conditions are compatible with a range of functional groups, and good chemoselectivity is observed with unsymmetric diaryliodonium salts. Furthermore, steric ...
Palm Gottfried J - - 2011
The highly thermostable esterase from the hyperthermophilic archaeon Pyrobaculum calidifontis VA1 (PestE) shows high enantioselectivity (E > 100) in the kinetic resolution of racemic chiral carboxylic acids, but little selectivity towards acetates of tertiary alcohols (E = 2-4). To explain these unique properties, its crystal structure has been determined at 2.0 Å resolution. The enzyme ...
Imaizumi Kinji - - 2011
We investigated the properties of 4,4'-biphenyl dicarboxylic acid diethyl ester (PCE). The PCE underwent a 2-step reduction at -1.5 V and -2.2 V. The color of the PCE changed from colorless to yellow in the first step and consequently to red in the second reduction step. A PCE based EC ...
Pinzi S - - 2011
The effect of fatty acids chain length (LC) and its interaction with unsaturation degree (UD) on important biodiesel quality parameters was studied. Low calorific value, kinematic viscosity, flash point, cetane number and cold filter plugging point of biodiesel blends covering a wide range of fatty acids were analyzed. Analytical results ...
Sanz José L - - 2011
Río Tinto (Iberian Pyritic Belt, SW Spain) is well known for its low pH (mean pH 2.3), high redox potential (> +400 mV) and high concentration of heavy metals. In this work we describe and analyse the presence of methanogenic archaea in the extreme acidic and oxidizing environment of the Tinto basin. ...
Semrau Jeremy D - - 2011
Methanotrophs are a group of phylogenetically diverse microorganisms characterized by their ability to utilize methane as their sole source of carbon and energy. Early studies suggested that growth on methane could be stimulated with the addition of some small organic acids, but initial efforts to find facultative methanotrophs, i.e., methanotrophs ...
Watanabe Masayuki - - 2011
Rumex obtusifolius L., a member of Polygonaceae, is one of the world's worst weeds. We characterized the glucosylceramide molecular species in leaves of R. obtusifolius by liquid chromatography/tandem mass spectrometry. 4,8-Sphingadienines were principally paired with 2-hydroxy palmitic acids. In contrast, 4-hydroxy-8-sphingenines were chiefly attached to 2-hydroxy fatty acids with 22 ...
Fitzgerald Mark - - 2011
  The organic peroxide explosive triacetone triperoxide (TATP) is regularly encountered by law enforcement agents in various stages of its production. This study utilizes solid-phase microextraction (SPME) and gas chromatography/mass spectrometry (GC/MS) to examine sulfuric acid-, hydrochloric acid-, and nitric acid-catalyzed TATP syntheses during the initial 24 h of these reactions ...
He Yuanhua - - 2011
The advanced oxidation processes of sonolysis (213 kHz), photocatalysis and a hybrid combination of both (sonophotocatalysis) have been used in the degradation of a representative aromatic carboxylic acid, p-chlorobenzoic acid (PCBA), in ambient air saturated aqueous solutions. The formation of degradation products were monitored quantitatively and qualitatively using HPLC and ...
Hamura Toshiyuki - - 2011
Alkenyl alkynyl ketones and ketene silyl acetals (KSAs) undergo regioselective [2+2]-cycloaddition under thermal conditions, triggering domino pericyclic reactions en route to various poly-substituted salicylic acid derivatives.
Di Giacomo Marcello - - 2011
In this paper we report the stereoselective synthesis of alpha-D-C-mannosyl-(S)-amino acids exploiting, as a key step, an allylic alkylation of glycal-derived pi-allyl Pd(II) intermediates, prepared by oxidative addition of Pd(0) species to 2,3-unsaturated pyranosides (pseudoglycals). The reaction of 4,6-di-O-acetyl alpha-pseudoglucal carbonate 10a with racemic alanine-, valine-, and phenylalanine-derived azlactones gave ...
Lou Liping - - 2011
Acid treatment is a routine demineralization process to obtain black carbon (BC), but there has been little systematic research about its influence on BC's characteristics. In this study, elemental analysis, SEM, FTIR, and Boehm titration were used to investigate that effect. Our results showed that the acid treatment had little ...
Haynes Christopher A - - 2011
This study describes the use of a stable-isotope labeled precursor ([U-¹³C]palmitate) to analyze de novo sphingolipid biosynthesis by tandem mass spectrometry. It also describes factors to consider in interpreting the data, including the isotope's location (¹³C appears in three isotopomers and isotopologues: [M + 16] for the sphingoid base or ...
Roberts James M - - 2011
We measured isocyanic acid (HNCO) in laboratory biomass fires at levels up to 600 parts per billion by volume (ppbv), demonstrating that it has a significant source from pyrolysis/combustion of biomass. We also measured HNCO at mixing ratios up to 200 pptv (parts-per-trillion by volume) in ambient air in urban ...
Harding A P - - 2011
The prediction of pK(a) from a single ab initio bond length has been extended to provide equations for benzoic acids and anilines. The HF/6-31G(d) level of theory is used for all geometry optimisations. Similarly to phenols (Part 2 of this series of publications), the meta-/para-substituted benzoic acids can be predicted ...
Thierry Anne - - 2011
Dairy propionibacteria are Actinobacteria, mainly isolated from dairy environments. Propionibacterium freudenreichii has been used for a long time as a ripening culture in Swiss-type cheese manufacture, and is more and more considered for its potent probiotic effects. This review summarises the knowledge on the main P. freudenreichii pathways and the ...
Betz Richard - - 2011
The title compound, C(7)H(4)ClFO(2), is a twofold halogenated derivative of benzoic acid. The C-C-C angles within the aromatic moiety cover a range 116.11 (14)-123.96 (15)°, with the maximum and the minimum value next to each other. In the crystal, O-H⋯O hydrogen bonds form carb-oxy-lic acid dimers, which are further connected by C-H⋯F ...
Ramachandran Kasirajan - - 2011
Al(HSO(4))(3) heterogeneous acid catalyst was prepared by the sulfonation of anhydrous AlCl(3). This catalyst was employed to catalyze transesterification reaction to synthesis methyl ester when a mixed waste vegetable oil was used as feedstock. The physical and chemical properties of aluminum hydrogen sulphate catalyst were characterized by scanning electron microscopy ...
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