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Results 401 - 450 of 1405
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Simo Mpetga James D - - 2012
Five new triterpenoids, caloncobic acids A and B (1 and 2), caloncobalactones A and B (3 and 4), and glaucalactone (5), along with the known compounds 3β,21β-dihydroxy-30-nor-(D:A)-friedo-olean-20(29)-en-27-oic acid (6) and acetyltrichadenic acid B (7), were isolated from the leaves of Caloncoba glauca. The structures of 1-5 were elucidated using spectroscopic ...
Gao Jian - - 2012
Convenient synthetic strategy toward spinasaponin A methyl ester 1 and calenduloside G methyl ester 2, two natural oleanane-type triterpenoid saponins bearing an unique β-d-glucosyl/galactosyl-(1→3)-β-d-glucuronic acid methyl ester disaccharide moiety, was established. Based on this facile approach, four structurally modified congeners 3-6 with ursolic acid and glycyrrhetinic acid as aglycones were ...
Rao Ramisetti Nageswara - - 2012
(R)-(-)-α-Methoxy phenyl acetic acid, (S)-(-)-1,1'-(2-naphthol), and (R)-(+)-α-methoxy-α-trifluoromethyl phenyl acetic acid were evaluated as chiral shift reagents (CSRs) for (1) H NMR spectroscopic resolution and determination of R and S enantiomers of modafinil (MDL) in bulk drugs and formulations. Effects of the nature of CSR and the weight ratio of substrate ...
Lubin Jean-Bernard - - 2012
Sialic or nonulosonic acids are nine-carbon alpha ketosugars that are present in all vertebrate mucous membranes. Among bacteria, the ability to catabolize sialic acid as a carbon source is present mainly in pathogenic and commensal species of animals. Previously, it was shown that several Vibrio species carry homologues of the ...
Lin Qiang - - 2012
This investigation examined the effects of the inorganic carbon concentration (4, 0.8 and 0g/L NaHCO(3)) on the carbon formation, nitrate utilization, growth and fatty acids compositions of Nannochloropsis oculata. The dissolved inorganic carbon (DIC) concentration in the three treatments decreased sharply during the first 6days, and the percentage of dissolved ...
Zhao Jin-Song - - 2012
The induced aggregation of achiral building blocks by a chiral species to form chiral aggregates with memorized chirality has been observed for a number of systems. However, chiral memory in isolated aggregates of achiral building blocks remains rare. One possible reason for this discrepancy could be that not much is ...
Aoki Nobuwa - - 2012
A new brominated C(17) acetylenic acid (1) designated as bromotheoynic acid has been isolated from the marine sponge Theonella swinhoei, collected off the coast of Tanegashima, Kagoshima Prefecture, Japan. The structure was determined on the basis of the analysis of its extensive 2D NMR spectroscopic data as well as HRMS. ...
Nahm Byung J - - 2012
A carbon dioxide laser operating at the highly absorbed wavelength of 9.3μm with a pulse duration of 10-15μs is ideally suited for caries removal and caries prevention. The enamel thermally modified by the laser has enhanced resistance to acid dissolution. This is an obvious advantage for caries prevention; however, it ...
Rudolf Christiane - - 2012
During fermentative metabolism, carbon dioxide fixation plays a key role in many bacteria regarding growth and production of organic acids. The present contribution, dealing with the facultative photosynthetic bacterium Rhodospirillum rubrum, reveals not only the strong influence of ambient carbon dioxide on the fermentative break-down of fructose but also a ...
Davalos Juan Zenon - - 2012
We have studied the energetics and structural properties of trans-cinnamic (CA), o-, m-, p-coumaric (2-, 3-, 4-hydroxycinnamic), caffeic (3,4-dihydroxycinnamic), ferulic (4-hydroxy-3-methoxycinnamic), iso-ferulic (3-hydroxy-4-methoxycinnamic) and sinapic (3,5-dimethoxy-4-hydroxycinnamic) acids. The experimental values of (g), determined (in kJ•mol-1) for CA (-229.8 ± 1.9), p-coumaric (-408.0 ± 4.4), caffeic (-580.0 ± 5.9) and ferulic ...
Schäfer André - - 2012
As you like it: The choice of solvents and substituents at the silicon atom determine what product is formed from carbon dioxide after electrophilic activation by silyl cations. Benzoic acid as well as the C-1 building blocks formic acid and methanol are on the product tableau.
Gómez Castaño Jovanny A - - 2012
The novel selenocarboxylic Se-acids, HCF(2)C(O)SeH and ClCF(2)C(O)SeH, were prepared by treating the corresponding carboxylic acids with Woollins' reagent. The boiling points were extrapolated from the vapor pressure curves to be 364 and 359 K for HCF(2)C(O)SeH and ClCF(2)C(O)SeH, respectively. Both compounds are unstable at ambient temperatures and decompose to the ...
Weylandt Karsten H - - 2012
Omega-3 polyunsaturated fatty acids (n-3 PUFAs) have long been associated with decreased inflammation and are also implicated in the prevention of tumorigenesis. Conventional thinking attributed this mainly to a suppressive effect of these fatty acids on the formation of arachidonic acid-derived prostaglandins and leukotrienes. Recent years have seen the discovery ...
Hadi Mojtaba - - 2012
Nanocrystalline graphite-like pyrolytic carbon film (PCF) electrode fabricated by a non-catalytic chemical vapor deposition (CVD) process was used for the simultaneous electrochemical sensing of ascorbic acid (AA), dopamine (DA), and uric acid (UA). The electrode was studied with respect to changes in electrocatalytic activity caused by a simple and fast ...
Kosová Klára - - 2012
Hormonal changes accompanying the cold stress (4°C) response that are related to the level of frost tolerance (FT; measured as LT50) and the content of the most abundant dehydrin, WCS120, were compared in the leaves and crowns of the winter wheat (Triticum aestivum L.) cv. Samanta and the spring wheat ...
Arslan-Alaton Idil - - 2012
The present paper deals with the effects of frequently used textile preparation chemicals and common ions on the H2O2/UV-C treatment of a commercially important and slowly biodegradable nonionic surfactant, namely a nonylphenol bearing 10 ethoxylated chains. For this purpose, the effect of soda ash carbonate (0-5.0 g L(-1)), two phosphonic ...
Tao Si-Jia - - 2012
Microbial transformation of gambogenic acid (1), a caged polyprenylated xanthone isolated from the resin of Garcinia hanburyi, was carried out with Chaetomium globosum CICC 2445, after screening forty-six strains of filamentous fungi. A new caged polyprenylated xanthone, 16,17-dihydroxygambogenic acid (2), was specifically obtained, as a result of hydroxylation at C-16, ...
Felchner-Zwirello Monika - - 2012
Biowaste digestion is a possibility to gain biogas as a renewable fuel source. However, the anaerobic food chain may be disrupted by, e.g., substrate overload or by inhibitors, leading to the accumulation of volatile fatty acids (VFAs), predominantly of propanoic acid (PA). VFA Accumulation may cause a rapid pH decrease, ...
Badrinarayanan Sandhya - - 2012
The dimerization of amino acid-derived α-amino aldehydes provides a short, biomimetic synthesis of several 2,5-disubstituted pyrazine natural products. The α-amino aldehyde intermediates were generated in situ by the hydrogenolysis of their Cbz-derivatives. It was found that a judicious choice of reaction solvent facilitated hydrogenolysis, dimerization and oxidation to the natural ...
Stierle Andrea A - - 2012
Berkeley Pit Lake, Butte, Montana, is a 540 m deep abandoned open-pit copper mine filled with over 140 billion liters of acidic, metal-sulfate-contaminated water. This harsh environment has yielded several microorganisms that produce interesting biologically active compounds. Several polyketide metabolites including the new berkazaphilones A (1) and B (2) and ...
Hu Youcai Y Department of Biochemistry, Division of Chemistry, University of Texas Southwestern Medical Center, 5323 Harry Hines, Blvd, Dallas, TX 75390-9038, - - 2012
A new peptide, L-O-Lac-L-Val-D-O-Hiv-D-Val (1), consisting of D-valine, L-valine, L-lactic acid, and 3-D-hydroxyisovaleric acid, was isolated from the culture of the marine sediment derived Streptomyces bacillaris. The planar structure of compound 1 was assigned by 1D, 2D NMR and mass spectroscopic analyses. Following acid and base hydrolysis, the absolute configuration ...
Clark Valerie C - - 2012
The skins of Madagascar poison frogs (Mantella) and certain Neotropical poison frogs (Epipedobates, Dendrobates) secrete the new bile acid tauromantellic acid (1), which was found in both wild-caught and captive-born frogs. This is the first molecule of endogenous origin detected in skin secretions from these taxa. Sucrose was also detected ...
Li Ming-Fei - - 2012
Fractionation of lignocellulosic material into its constitutive components is of vital importance for the production of biofuels as well as other value-added chemicals. The conventional acetosolv processes are mainly focused on the production of pulp from woody lignocelluloses. In this study, a mild acetosolv process was developed to fractionate bamboo ...
Zhou Zhong-Yu - - 2012
Life saver: Two unusual and toxic amino acids, 2R-amino-4S-hydroxy-5-hexynoic acid (red, see scheme) and 2R-amino-5-hexynoic acid (blue) have been isolated from the fruiting bodies of the mushroom Trogia venenata. Toxicology studies suggest that these compounds may be the cause of Sudden Unexplained Death (SUD) in Yunnan Province, China.
Vysotsky Yuri B - - 2012
In the frameworks of the quantum-chemical semiempirical PM3 method, the thermodynamic parameters of trans-isomers of unsaturated carboxylic acids at the air/water interface were studied. Systems with 18-26 carbon atoms in the alkyl chain and different positions of the double bond are considered. Using quantum-chemical semiempirical PM3 method enthalpy, Gibbs' energy ...
Hosoya Takahiro - - 2012
Three new trichostatin analogues, JBIR-109 (1), JBIR-110 (2), and JBIR-111 (3), were isolated from the culture of the marine sponge-derived Streptomyces sp. strain RM72, together with trichostatin A (4) and trichostatic acid (5). The planar structures of 1-3 were determined on the basis of extensive NMR and MS analyses. In ...
Sudjaroen Yuttana - - 2012
Longan (Dimocarpus longan Lour, syn. Euphoria longan Lam.) represents an important fruit in Northern Thailand and has significant economic impact. The fruit is either consumed fresh or as commercially prepared dried and canned products. The canning industry in Thailand produces considerable quantities of waste products, in particular Longan seeds. Because ...
Munyololo Muganza - - 2012
Two further variations of the Ferrier-type allylic rearrangements of 1,2-cyclopropanated glucose derivatives bearing an acetoxylated carbon at the 1'-position are described. In the first, treatment of the cyclopropanated sugar with a nucleophile (ROH, PhSH, azide) and Lewis acid (BF(3)·Et(2)O or Al(OTf)(3)), gives 2-C-vinyl glucosides in good yields and α-selectivities. Alternatively, ...
Nagoba Basavraj S - - 2012
A prospective study was carried out to assess the role of citric acid as a sole antimicrobial agent in the management of lepromatous ulcers. Thirty-four known cases of lepromatous ulcers not responding to conventional antibiotic therapies for long duration were investigated for culture and susceptibility studies. Staphylococcus aureus (25·00%) and ...
Rohof W O - - 2012
BackgroundThe risk for acidic reflux is mainly determined by the position of the gastric acid pocket. It was hypothesised that compounds affecting proximal stomach tone might reduce gastro-oesophageal reflux by changing the acid pocket position.ObjectiveTo study the effect of azithromycin (Azi) on acid pocket position and acid exposure in patients ...
Sands Jeffrey J - - 2012
Background: Citrasate®, citric acid dialysate (CD), contains 2.4 mEq of citric acid (citrate), instead of acetic acid (acetate) as in standard bicarbonate dialysate. Previous studies suggest CD may improve dialysis adequacy and decrease heparin requirements, presumably due to nonsystemic anticoagulant effects in the dialyzer. Methods: We prospectively evaluated 277 hemodialysis ...
Jöris Monique M - - 2012
Previously, we showed that with an increasing number of amino acid differences in single HLA class I-mismatched molecules, the probability of T cell alloreactivity decreases. It is unlikely that every amino acid difference will affect T cell alloreactivity in a similar way; we hypothesized that the effect of an amino ...
Rahbar Nahid - - 2012
OBJECTIVE: To examine whether dietary supplementation with omega-3 fatty acids relieved symptoms of primary dysmenorrhea. METHODS: Women aged 18-22years with primary dysmenorrhea were enrolled in a double-blind crossover study. Women assigned to group 1 (n=47) received 1 omega-3 capsule daily for 3months, followed by placebo for 3months. Women in group ...
Naoulou Becky - - 2012
Objective. To evaluate the efficacy of tranexamic acid in the treatment of idiopathic and non-functional heavy menstrual bleeding. Design. Systematic review. Population: Women with diagnosis of idiopathic and non-functional heavy menstrual bleeding treated with tranexamic acid. Method. Electronic searches were conducted in literature database up to February 2011 by 2 ...
Arunadevi N - - 2012
The title molecular salts, N(2)H(5)(+)·C(7)H(5)O(3)(-)·C(7)H(6)O(3) and N(2)H(5)(+)·C(11)H(7)O(3)(-)·C(11)H(8)O(3), are acid adducts containing a hydrazinium cation, one molecule of a deprotonated acid and one molecule of a neutral acid. The two compounds contain essentially identical hydrogen-bond networks between the hydrazinium cation and the acid molecules, which define closely comparable two-dimensional layers in ...
Tomshich S V - - 2012
The O-specific polysaccharide was obtained by mild acid degradation of the lipopolysaccharide of the marine bacterium Arenibacter palladensis type strain KMM 3961(T) and studied by chemical methods and (1)H and (13)C NMR spectroscopy including 2D COSY, TOCSY, (1)H,(13)C HSQC, and HMBC experiments. The polysaccharide was shown to consist of tetrasaccharide ...
Zhang Yong-Hong - - 2012
A new chiro-inositol ester, 4-hydroxyphenylacetyl-3-d-chiro-inositol ester (1), was isolated from the whole plants of Prenanthes macrophylla Franch., along with 10 known compounds, 4-hydroxyphenylacetic acid (2), trans-ethyl caffeate (3), cis-ethyl caffeate (4), protocatechualdehyde (5), luteolin (6), luteolin-7-O-β-d-glucoside (7), 15-hydroxy-2-oxo-guai-3-en-1α,5α,6β,7α,10α,11βH-12,6-olide (8), 15-glucopyranosyloxy-2-oxo-guaia-3,11(13)-dien-1α,5α,6β,7α,10αH-12,6-olide (9), ursolic acid (10), and oleanolic acid (11). Their structures ...
Aoki Syota - - 2012
Six new secoiridoid constituents, named isoligustrosidic acid (1), 6'-O-trans-cinnamoyl 8-epikingisidic acid (2), 6'-O-cis-cinnamoyl 8-epikingisidic acid (3), oleopolynuzhenide A (4), nuzhenals A (5) and B (6) were isolated from the dried fruits of Ligustrum lucidum AIT. Their structures were established on the basis of spectral and chemical data.
Salinero Carmen - - 2012
<em>Camellia japonica </em>(CJ) has oil-rich seeds, but the study of these oils has received little attention and has mainly focused only on their health properties. In the present work the relative composition of the fatty acid (FA) components of the triglycerides in cold-pressed oil from CJ is studied by <sup>1</sup>H-NMR. ...
Yeddes Nizar - - 2012
The fatty acids profiles of Tunisian Opuntia ficus indica seeds (spiny and thornless form) were investigated. Results of supercritical carbon dioxide (SC-CO(2)) and soxhlet n-hexane extract were compared. Quantitatively, the better yield was obtained through soxhlet n-hexane: 10.32% (spiny) and 8.91% (thornless) against 3.4% (spiny) and 1.94% (thornless) by SC-CO(2) ...
Wu Haifeng - - 2012
From the whole plant of <em>Sarcandra glabra</em>,<strong> </strong>a new phenolic acid glycoside, benzyl 2-β-glucopyranosyloxybenzoate (<strong>1</strong>), together with seven known compounds including eleutheroside B<sub>1</sub> (<strong>2</strong>), 5-<em>O</em>-caffeoylshikimic acid (<strong>3</strong>), (-)-(7<em>S</em>, 8<em>R</em>)-dihydrodehydro-diconiferyl alcohol (<strong>4</strong>), (-)-(7<em>S</em>, 8<em>R</em>)-dihydrodehydrodiconiferyl alcohol 9-, 9'- and 4-<em>O</em>-â-D-glucopyranoside (<strong>5</strong>-<strong>7</strong>), and (-)-(7<em>S</em>, 8<em>R</em>)-5-methoxydihydrodehydrodiconiferyl alcohol 4-<em>O</em>-β-D-glucopyranoside (<strong>8</strong>) was isolated. Their structures were ...
She Gaimei - - 2012
Dried sclerotia of Wolfiporia extensa (Polyporaceae) is used to invigorate the spleen and to tranquilize the mind in Chinese herbal medicine. Lanostane-type triterpene acids were regard as major secondary metabolites from dried sclerotia of W. extensa. Three new lanostane-type triterpene acids, 3-epi-benzoyloxyl-dehydrotumulosic acid (1), 3-epi-(3'-O-methyl malonyloxy)-dehydrotumulosic acid (2) and 3-epi-(3'-hydroxy-3'-methylglutaryloxyl)-dehydrotumulosic ...
Mulopo J - - 2012
The conversion of steelmaking slag (a waste product of the steelmaking process) to calcium carbonate (CaCO(3)) was tested using hydrochloric acid, ammonium hydroxide and carbon dioxide via a pH-swing process. Batch reactors were used to assess the technical feasibility of calcium carbonate recovery and its use for pre-treatment of acid ...
Jala Ram Chandra Reddy - - 2012
Structured lipids (SL) are broadly referred to as modified or synthetic oils and fats or lipids with functional or pharmaceutical applications. Some structured lipids, such as triglycerides that contain both long-chain (mainly essential) fatty acids and medium- or short-chain fatty acids and also artificial products that mimic the structure of ...
Ji De - - 2012
A new iridoid glycoside, named loganic acid ethyl ester (1), together with five known compounds: chlorogenic acid (2), caffeic acid (3), loganin (4), cantleyoside (5) and syringaresinol-4',4''-O-bis-β-D-glucoside (6) were isolated from the roots of Dipsacus asper. The structure of compound 1 was elucidated on the basis of detailed spectroscopic analyses. ...
Zhu Chen-Chen - - 2012
A new triterpenoid saponin and fourteen known triterpenoids were isolated from the methanol extract of the stems and leaves of Callicarpa integerrima Champ, which is used in Chinese folk medicine for stopping bleeding, expelling the wind, dissipating stagnation, and treating scrofula, by using various chromatographies, such as silica gel, Sephadex ...
Hazar-Yoruc Binnaz - - 2012
This study investigated the erosion kinetics of conventional and resin-modified glass-ionomer luting cements in acidic buffer solutions as a function of time. Disc shaped specimens were prepared from conventional (Ketac-Cem: KTC) and resin-modified glass ionomer cements (Fuji Plus: FP) and immersed in three acidic buffer solutions (0.01 M) namely, acetic ...
Almeida Verônica M - - 2012
Naringin is an important flavanone with several biological activities, including antioxidant action. However, this compound shows low solubility in lipophilic preparations, such as is used in the cosmetic and food industries. One way to solve this problem is to add fatty acids to the flavonoid sugar unit using immobilized lipase. ...
Kinuthia Esther W - - 2012
A new triterpenoid, 3-oxo-22alpha-hydroxy-olean-12-en-28-oic acid (1), oleanolic acid (2) and a known iridoid, 10-hydroxy-1-oxo-7-iriden-11-oic acid methyl ester (3) have been isolated from the dichloromethane extract of the dried seeds of Gardenia volkensii. Their structures were established by 1D and 2D NMR spectroscopic and MS methods.
Hadibarata Tony - - 2012
Armillaria sp. F022, a white rot fungus isolated from tropical rain forest (Samarinda, Indonesia) was used to biodegrade naphthalene in cultured medium. Transformation of naphthalene by Armillaria sp. F022 which is able to use naphthalene, a two ring-polycyclic aromatic hydrocarbon (PAH) as a source of carbon and energy was investigated. ...
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