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O'Reilly Robert J - - 2011
Quantum chemistry computations have been used to investigate hydrogen-atom abstraction by chlorine atom from protonated and N-acetylated amino acids. The results are consistent with the decreased reactivity at the backbone α-carbon and adjacent side-chain positions that is observed experimentally. The individual effects of NH(3)(+), COOH, and NHAc substituents have been ...
Ozeir Mohammad - - 2011
Coenzyme Q (Q), an essential component of eukaryotic cells, is synthesized by several enzymes from the precursor 4-hydroxybenzoic acid. Mutations in six of the Q biosynthesis genes cause diseases that can sometimes be ameliorated by oral Q supplementation. We establish here that Coq6, a predicted flavin-dependent monooxygenase, is involved exclusively in ...
Amador-Noguez Daniel - - 2011
The fermentation carried out by the biofuel producer Clostridium acetobutylicum is characterized by two distinct phases. Acidogenesis occurs during exponential growth and involves the rapid production of acids (acetate and butyrate). Solventogenesis initiates as cell growth slows down and involves the production of solvents (butanol, acetone, and ethanol). Using metabolomics, ...
Naganuma Tatsuro - - 2011
Very long-chain fatty acids (VLCFAs) have a variety of physiological functions and are related to numerous disorders. The key step of VLCFA elongation is catalyzed by members of the elongase family, ELOVLs. Mammals have seven ELOVLs (ELOVL1-7), yet none of them has been purified and analyzed. In the presented study ...
Ye Xiang-Yang - - 2011
Starting from high throughput screening hit 2-adamantyl acetic acid 3, a series of polycyclic acids have been designed and synthesized as novel, potent, and selective inhibitors of human 11β-HSD-1. Structure-activity relationships of two different regions of the chemotype (polycyclic ring and substituents on quaternary carbon) are discussed.
Hazra Montu K - - 2011
Computational studies at the B3LYP/6-311++G(3df,3pd) and MP2/6-311++G(3df,3pd) levels are performed to explore the changes in reaction barrier height for the gas phase hydrolysis of SO<sub>3</sub> to form H<sub>2</sub>SO<sub>4</sub> in the presence of a single formic acid (FA) molecule. For comparison, we have also performed calculations for the reference reaction involving ...
Zhang Chaoyang - - 2011
The stored and wasted explosives are usually in an acid or alkali environment, leading to the importance of exploring the acid and alkali effects on the decomposition mechanism of explosives. The acid and alkali effects on the decomposition of HMX molecule in gaseous state and in aqueous solution are studied ...
Agarwal Arun S - - 2011
The engineering and economic feasibility of large-scale electrochemical reduction of carbon dioxide to formate salts and formic acid is the focus of this Full Paper. In our study we investigated the long-term performance of tin and other proprietary catalysts in the reduction of carbon dioxide to formate/formic acid at a ...
Siotto Michela - - 2012
In modern intensive agriculture, plastics are used in several applications (i.e. mulch films, drip irrigation tubes, string, clips, pots, etc.). Interest towards applying biodegradable plastics to replace the conventional plastics is promising. Ten monomers, which can be applied in the synthesis of potentially biodegradable polyesters, were tested according to ASTM ...
Li Yanjie - - 2011
Properties improvement of paper mill sludge (PMS) based granular activated carbon fillers for fluidized-bed bioreactor (FBBR) was investigated in this study. Bentonite (Na) powders were blended in the dewatered paper mill sludge powders to strengthen the abrasion resistance strength of the fillers. Different acid washing treatments were studied to produce ...
Cha Thye San - - 2011
This study was undertaken to investigate the effects of different nitrate concentrations in culture medium on oil content and fatty acid composition of Chlorella vulgaris (UMT-M1) and Chlorella sorokiniana (KS-MB2). Results showed that both species produced significant higher (p<0.05) oil content at nitrate ranging from 0.18 to 0.66mM with C. ...
Olutoye M A - - 2011
Fatty acid methyl esters (FAME) were produced from palm oil using eggshell modified with magnesium and potassium nitrates to form a composite, low-cost heterogeneous catalyst for transesterification. The catalyst, prepared by the combination of impregnation/co-precipitation was calcined at 830°C for 4h. Transesterification was conducted at a constant temperature of 65°C ...
Fuchibe Kohei - - 2011
In order to synthesize polycyclic aromatic hydrocarbons with nonlinear arrangements (angular PAHs), acid-promoted domino cyclizations of 1,1-difluoroalk-1-enes and 1,1-difluoroalka-1,3-dienes were studied. 1,1-Difluoroalkenes, each bearing two aryl substituents, were regioselectively protonated with FSO(3) H⋅SbF(5) to generate fluorine-stabilized carbocations, which readily underwent domino Friedel-Crafts-type cyclizations to give carbocycles based on 6/n/m/6 ring ...
Wang Cun - - 2011
A novel biosensor has been constructed by the electrodeposition of Au-nanoclusters (nano-Au) on poly(3-amino-5-mercapto-1,2,4-triazole) (p-TA) film modified glassy carbon electrode (GCE) and employed for the simultaneous determination of dopamine (DA), ascorbic acid (AA), uric acid (UA) and nitrite (NO(2)(-)). NH(2) and SH groups exposed to the p-TA layer are helpful ...
Coimbra Michelle C - - 2011
BACKGROUND: Bioactive compounds are capable of providing health benefits, reducing disease incidence or favoring body functioning. There is a growing search for vegetable oils containing such compounds. This study aimed to characterize the pulp and kernel oils of the Brazilian palm species guariroba (Syagrus oleracea), jerivá (Syagrus romanzoffiana) and macaúba ...
Sharma Upendra K - - 2011
BACKGROUND: Decarboxylation of substituted cinnamic acids is a predominantly followed pathway for obtaining hydroxystyrenes-one of the most extensively explored bioactive compounds in the food and flavor industry (e.g. FEMA GRAS approved 4-vinylguaiacol). For this, mild and green strategies providing good yields with high product selectivity are needed. RESULTS: Two newly ...
Keil Richard - - 2011
Organic compounds were evaluated in March 2010 at 22 stations in Barkley Sound, Vancouver Island Canada and at 66 locations in Puget Sound. Of 37 compounds, 15 were xenobiotics, 8 were determined to have an anthropogenic imprint over natural sources, and 13 were presumed to be of natural or mixed ...
Ukrainczyk Marko - - 2011
Investigation of basic interactions between the active pharmaceutical compounds and calcium carbonates is of great importance because of the possibility to use the carbonates as a mineral carrier in drug delivery systems. In this study the mode and extent of interactions of salicylic acid and its amino acid derivates, chosen ...
Gómez-Bombarelli Rafael - - 2011
Hydroxyhalofuranones form a group of genotoxic disinfection by-products (DBP) of increasing interest. Among them, mucohalic acids (3,4-dihalo-5-hydroxyfuran-2(5H)-one, MXA) are known mutagens that react with nucleotides, affording etheno, oxaloetheno and halopropenal derivatives. In this work, the alkylation kinetics of mucochloric and mucobromic acids has been studied from both the empirical and ...
Dozzi Maria Vittoria - - 2011
The photocatalytic behaviour of a series of ammonium fluoride (NH(4)F)-doped titania (TiO(2)) photocatalysts was investigated in the decomposition of acetic acid in aqueous suspensions and in the gas phase mineralization of acetaldehyde. Very similar photocatalytic activity trends, usually increasing with increasing the calcination temperature for a given nominal dopant amount, ...
Rezanka Tomáš - - 2011
The yellow-green alga Trachydiscus minutus (Eustigmatophyceae, Heterocontophyta) was cultivated in a standard medium and under nitrogen- and phosphorus-starvation and its triacylglycerols were analyzed by RP-HPLC/MS-APCI. The molecular species of triacylglycerols included a total of 74 triacylglycerols having at least one polyunsaturated fatty acid. Polyunsaturated triacylglycerols were identified for the first ...
Wang Yingying - - 2011
This study was reported on a novel process for fatty acid ethyl esters preparation by transesterification and esterification from renewable low-cost feedstock camellia oil soapstocks and friendly acyl acceptor diethyl carbonate. The main components of product were 83.9% ethyl oleate, 8.9% ethyl palmitate, 4.7% ethyl linoleate and 2.1% ethyl stearate, ...
Ohara-Nemoto Yuko - - 2011
Porphyromonas gingivalis and Porphyromonas endodontalis, asaccharolytic black-pigmented anaerobes, are predominant pathogens of human chronic and periapical periodontitis, respectively. They incorporate di- and tripeptides from the environment as carbon and energy sources. In the present study we cloned a novel dipeptidyl peptidase (DPP) gene of P. endodontalis ATCC 35406, designated as ...
Rühl Jana J Laboratory of Chemical Biotechnology, Department of Biochemical and Chemical Engineering, TU Dortmund, Emil-Figge-Str. 66, 44221 Dortmund, - - 2012
Microorganisms, such as Pseudomonas putida, utilize specific physical properties of cellular membrane constituents, mainly glycerophospholipids, to (re-)adjust the membrane barrier to environmental stresses. Building a basis for membrane composition/function studies, we inventoried the glycerophospholipids of different Pseudomonas and challenged membranes of growing cells with n-butanol. Using a new high-resolution liquid ...
Mellert W - - 2011
Metabolite profiling (metabolomics) elucidates changes in biochemical pathways under various conditions, e.g., different nutrition scenarios or compound administration. BASF and metanomics have obtained plasma metabolic profiles of approximately 500 compounds (agrochemicals, chemicals and pharmaceuticals) from 28-day rat studies. With these profiles the establishment of a database (MetaMap(®)Tox) containing specific metabolic ...
Xu Huijuan - - 2011
This study investigated the effect of d-tyrosine on microbial attachment to hydrophilic glass and hydrophobic polypropylene surfaces. Results showed that d-tyrosine did not influence microbial growth, ATP and substrate utilization, but significantly inhibited the synthesis of autoinducer-2 (AI-2), eDNA and extracellular polysaccharides and proteins, and subsequently reduced microbial attachment onto ...
Zhuang Wei-Qin - - 2011
Bacteria of the genus Dehalococcoides are important members of bioremediation communities because of their ability to detoxify chloroethenes to the benign end product ethene. Genome-enabled studies conducted with Dehalococcoides ethenogenes 195 have revealed that two ATP-binding cassette (ABC)-type amino acid transporters are expressed during its exponential growth stages. In light ...
Alhooshani Khalid - - 2011
For the first time, haloacetic acids and aromatic acetic acids were extracted from wastewater samples using electromembrane extraction (EME). A thin layer of toluene immobilized on the walls of a polypropylene membrane envelope served as an artificial supported liquid membrane (SLM). The haloacetic acids (HAAs) (chloroacetic acid, dichloroacetic acid, and ...
Schmitt Daniel C - - 2011
Three-component coupling of the lithium enolate of t-BuOAc, silyl glyoxylate, and an α,β-unsaturated ketone enables the rapid construction of the trachyspic acid carbon skeleton. A 3,4-disubstituted isoxazole is utilized to mask the C7/C9 dicarbonyl. New enolsilane/nitrile-oxide cycloadditions enable the preparation of various 3,4-disubstituted isoxazoles that are challenging to access by ...
Ratanapariyanuch Kornsulee - - 2011
Thin stillage contains organic and inorganic compounds, some of which may be valuable fermentation co-products. This study describes a thorough analysis of the major solutes present in thin stillage using NMR and HPLC. The concentration of charged and neutral organic compounds in thin stillage was determined by excitation sculpting NMR ...
Hitaoka Seiji - - 2011
We carried out full ab initio fragment molecular orbital (FMO) calculations for complexes comprising human neuraminidase-2 (hNEU2) and sialic acid analogues including antiinfluenza drugs zanamivir (Relenza) and oseltamivir (Tamiflu) in order to examine the variation in the observed inhibitory activity toward hNEU2 at the atomic and electronic levels. We recently ...
Ng Seik Weng - - 2011
The unit cell of the title compound, C(7)H(6)O(4)·H(2)O, features four independent formula units; the individual carb-oxy-lic acid mol-ecules themselves are nearly planar (r.m.s. deviations = 0.0189, 0.0334, 0.0356 and 0.0441 Å). Two independent mol-ecules each form two hydrogen bonds by acid-carbonyl O-H⋯O inter-actions and the dimers are also nearly planar (r.m.s. ...
Pasquevich M Y - - 2011
While invertebrates store neutral lipids as their major energy source, little is known about triacylglycerol (TAG) class composition and their differential catabolism in aquatic arthropods. This study focuses on the composition of the main energy source and its catabolism by lipase from the midgut gland (hepatopancreas) of the crustacean Macrobrachium ...
Usuki Toyonobu - - 2011
Shikimic acid, the starting material in the commercial synthesis of oseltamivir phosphate (Tamiflu®), was efficiently extracted and isolated from Ginkgo biloba leaves utilizing the ionic liquid 1-butyl-3-methylimidazolium chloride ([bmim]Cl), which dissolves cellulose.
Kirkby Jasper J CERN, CH-1211 Geneva, Switzerland. - - 2011
Atmospheric aerosols exert an important influence on climate through their effects on stratiform cloud albedo and lifetime and the invigoration of convective storms. Model calculations suggest that almost half of the global cloud condensation nuclei in the atmospheric boundary layer may originate from the nucleation of aerosols from trace condensable ...
Rivero-Chan Braulio E - - 2011
We describe in this article a process with which to obtain different ketones related to oleanolic and ursolic acids from a natural source, Salvia canariensis L., with minimal use of chromatography columns. Amongst the isolated compounds was 12α-bromo-3-oxo-olean-13, 28-olide (3), which was fully characterised, including a characterisation of its molecular ...
Gurinov Andrey A - - 2011
1H and variable temperature 15N NMR techniques have been used to study the effect of a gradual alumination of SBA-15 on the structure and adsorption properties of this mesoporous material. The interpretation of experimental spectra suggests that aluminum chlorhydrol most effectively reacts with silica surface in a confined geometry of ...
Sourabié Alain M - - 2011
Despite their importance as potent odors that contribute to the aroma of numerous cheeses, S-methyl thioesters formation pathways have not been fully established yet. In a first part of our work, we demonstrated that Brevibacterium antiquum and Brevibacterium aurantiacum could produce S-methyl thioesters using short-chain fatty acids or branched-chain amino ...
Lazzaroni Raffaello - - 2011
Indolizidine alkaloids have attracted considerable attention because of their vast array of structural diversity and varied biological activity. This article relates the results that we obtained in the field of the total synthesis of indolizidines from α-amino acids, based on the rhodium-catalyzed hydroformylation of N-allylpyrroles intermediates. The formed pyrrolylbutanals undergo ...
Nykiforuk Cory L - - 2011
Gamma linolenic acid (GLA; C18:3Δ6,9,12 cis), also known as γ-Linolenic acid, is an important essential fatty acid precursor for the synthesis of very long chain polyunsaturated fatty acids and important pathways involved in human health. GLA is synthesized from linoleic acid (LA; C18:2Δ9,12 cis) by endoplasmic reticulum associated Δ6-desaturase activity. ...
Meyers Marvin J - - 2011
Fatty acid amide hydrolase (FAAH) is an integral membrane serine hydrolase responsible for the degradation of fatty acid amide signaling molecules such as endocannabinoid anandamide (AEA), which has been shown to possess cannabinoid-like analgesic properties. Herein we report the optimization of spirocyclic 7-azaspiro[3.5]nonane and 1-oxa-8-azaspiro[4.5]decane urea covalent inhibitors of FAAH. ...
Olma A - - 2012
The cyclization of N-Boc-α-alkylserines to corresponding β-lactones under Mitsunobu reaction conditions and the ring opening with heterocyclic amines (pyrrolidine, piperidine, morpholine and thiomorpholine) produced N-Boc-α-alkyl-β-(sec-amino)alanines. The removal of the Boc group gives di-hydrochlorides of non-protein amino acids.
Averous J - - 2011
In mammals, the GCN2/ATF4 pathway has been described as the main pathway involved in the regulation of gene expression upon amino acid limitation. This regulation is notably conferred by the presence of a cis-element called Amino Acid Response Element (AARE) in the promoter of specific genes. In vivo, the notion ...
Truong Lien T N - - 2011
In this work, a sensitive label-free impedimetric hCG-immunosensor was constructed by using a commercial screen-printing carbon ink electrode (namely disposable electrochemical printed chip) as the basis. The carbon ink electrode of DEP chip is modified first by deposition of polypyrrole-pyrole-2-carboxylic acid copolymer and thence hCG antibody immobilization via the COOH ...
Adamiak Joanna - - 2011
A new catalyst, H(3)PO(4)/MoO(3)/SiO(2), was prepared by modification of MoO(3)/SiO(2) using phosphoric acid. The characterization of the catalyst was performed using Infrared and Raman Spectroscopy, potentiometric titration and nitrogen adsorption-desorption methods. Molybdenum oxides were identified along with phosphomolybdic acid and polymolybdates on the modified surface. The suitability of the catalysts ...
Zheng Purong - - 2011
Catalyzed by DBU or DBN, 2-acetoxy benzofuranones and 2-acetoxy-N-Tos indolin-3-ones, were readily prepared from o-acyl phenols and o-acyl anilines, respectively, reacted with H(2)O or a range of amines to afford o-OH and o-NH-Tos benzoic acids or benzoamides in moderate to excellent yields.
Trost Barry M - - 2011
Enabled by the broad scope of the Pd-catalyzed asymmetric alkylation of meso- and d,l-divinylethylene carbonate, several chiral diene ligands were prepared in two steps from commercial materials. Subsequently, these ligands were evaluated in the Rh-catalyzed asymmetric conjugate addition of boronic acids to enones.
Dellomonaco Clementina - - 2011
Advanced (long-chain) fuels and chemicals are generated from short-chain metabolic intermediates through pathways that require carbon-chain elongation. The condensation reactions mediating this carbon-carbon bond formation can be catalysed by enzymes from the thiolase superfamily, including β-ketoacyl-acyl-carrier protein (ACP) synthases, polyketide synthases, 3-hydroxy-3-methylglutaryl-CoA synthases, and biosynthetic thiolases. Pathways involving these enzymes ...
Economou Ch N - - 2011
Rice hull hydrolysate was used as feedstock for microbial lipids production using the oleaginous fungus Mortierella isabellina. Kinetic experiments were conducted in C/N ratios 35, 44 and 57 and the oil accumulation into fungal biomass was 36%, 51.2% and 64.3%, respectively. A detailed mathematical model was used in order to ...
Hattori Ryota - - 2011
Compound-specific carbon isotope analysis of acetic acid is useful for origin discrimination and quality control of vinegar. Intramolecular carbon isotope distributions, which are each carbon isotope ratios of the methyl and carboxyl carbons in acetic acid molecule, may be required to obtain more detailed information to discriminate such origin. In ...
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