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... 3, 4-Dihydroxybenzaldehydeisonicotinoylhydrazone was prepared, characterized with spectral analyses and used for developing a new method for the simple, sensitive and rapid spectrophotometric determination of vanadium(V) which gives maximum absorbance at wave length 360 nm. The metal ion gives a yellow colored complex with 3, 4-DHBINH in acetate buffer of pH 5.5 with 1:1 (metal:ligand) composition ...
gas production (biological); in vitro digestion; liquids; feed concentrates; ruminants; ruminant nutrition; rumen microorganisms; rumen fermentation; propionates; acetates; butyrates; forage evaluation; inoculum; volatile fatty acids; batch systems
Abstract:
... A simple and inexpensive in vitro feed evaluation system which estimates microbial fermentation by measuring gas production and allows for adjustment of liquid dilution rate has been design. Working conditions, in terms of substrate and inoculum proportions (experiment 1, EXP 1) and the liquid replacement schedule (experiment 2, EXP 2) were initially set. In EXP 1, three substrate concentrations ( ...
... A new irreversible esterification method for carboxylic acids catalyzed by a lipase from Candida antarctica (Novozyme 435) in organic solvents has been developed. The water produced during the process is chemically destroyed by a corresponding ester of acetoacetate, which acts as a sacrificial substrate in this reaction. The flavour esters isobutyl acetate, methyl butyrate, ethyl butyrate and benz ...
... This study examined the effects of brewers yeast, fructooligosaccharide (FOS), and GroBiotic®-A, a mixture of partially autolyzed brewers yeast, dairy components and dried fermentation products, on the intestinal microbial community of red drum, Sciaenops ocellatus. Gastrointestinal (GI) tracts were aseptically removed from three sub-adult red drum previously maintained on a commercial diet and pl ...
... Palladium-catalyzed transformations of aryl halides and pseudo-halides involving carbonylation, carbon–carbon and carbon–heteroatom bond-forming reactions, etc. are very well documented, and have already been reviewed several times. The metal-catalyzed activation of benzylic derivatives is much less described. However, during the last decades, a number of papers have shown the interest offered by ...
... The chloroplast ATP synthase gates the flow of protons out of the thylakoid lumen. In Chlamydomonas reinhardtii deletion of any of the genes for the ATP synthase subunits, or misfolding of the peptides results in photosynthetic membranes devoid of the enzyme (Lemaire and Wollman, J Biol Chem 264:675-685, 1989). This work examines the physiologic response of an algal strain in which the epsilon sub ...
... Rod-shaped Alphaproteobacteria possessing long prosthecae-like appendages have been detected abundantly in biofilms attaching onto anode graphite of cellulose-fed microbial fuel cells (MFCs). To identify their ecological roles, the present study isolated a corresponding bacterium (strain Mfc52) by direct plating of a biofilm suspension onto a solid medium containing glucose and ferric ion. Phyloge ...
... BACKGROUND: A single-stage reactor, in which the growth of bacterial culture, induction of desulfurizing enzymes, and desulfurization reaction are carried out in a single step, was adopted to investigate desulfurization of dibenzothiophene (DBT) at high cell densities. Rhodococcus erythropolis, IGTS8 was used as the biocatalyst. Optimal conditions for bacterial growth and DBT desulfurization were ...
... Marine biofilms are a virtually untapped source of bioactive molecules that may find application as novel antifoulants in the marine paint industry. This study aimed at determining the potential of marine biofilm bacteria to produce novel biomolecules with potential application as natural antifoulants. Nine representative strains were isolated from a range of surfaces and were grown in YEB medium ...
... Antimicrobial, antioxidant, and antiviral activities of flower extracts of Retama raetam Forssk. Webb (Fabaceae) were screened both from standard and isolated Gram-positive and Gram-negative bacteria by solid medium technique. Oxacillin, Amoxicillin, Ticarcillin, Cefotaxim, and Amphotericin were used as the control agents. The antiviral activity was evaluated against human cytomegalovirus (HCMV) s ...
... The search for natural antioxidants, especially of plant origin, has notably increased in recent years. Bunium persicum Boiss. is an economically important medicinal plant growing wild in the dry temperature regions in Iran. In this study, chemical constituents of the essential oil of the seed from Bunium persicum Boiss. have been studied by GC/MS technique. The major components were caryophyllene ...
... Cinnamomum osmophloeum Kaneh. is an indigenous tree species in Taiwan. In this study, phytochemical characteristics and antioxidant activities of ethanolic extracts from the twigs of C. osmophloeum were investigated for the first time. The extracts were obtained successively using liquid-liquid partition to yield n-hexane (Hex), ethyl acetate (EtOAc), n-butanol (BuOH) and water fractions. The anti ...
... The present study was designed to explore the antioxidant potential of chloroform, ethyl acetate, n-butanol and water fractions of 80% methanol extract of leaves Chukrasia tabularis by 2,2'-diphenyl-1-picrylhydrazyl (DPPH), deoxyribose degradation (non-site specific and site specific), reducing power and DNA nicking assays. The different fractions showed significant activities in all the free radi ...
... In vitro antioxidant activities of three selected Indian red seaweeds - viz., Euchema kappaphycus, Gracilaria edulis and Acanthophora spicifera were evaluated. Total phenolic content and reducing power of crude methanol extract were determined. The antioxidant activities of total methanol extract and five different solvent fractions (viz., petroleum ether (PE), ethyl acetate (EA), dichloromethane ...
... This study was conducted to determine the composition of essential oil and headspace from Elsholtzia splendens, and to determine the aroma-active compounds of this aromatic plant. Eighty-five components were identified in the oil by GC and GC-MS. The major compounds were naginata ketone (70.43%) and elsholtzia ketone (4.95%). Sixty-eight volatile flavour constituents were detected in the headspace ...
Cephus cinctus; acetates; adults; air; air flow; beta-ocimene; bioassays; females; grasses; males; oviposition; pest management; sawflies; stems; volatile compounds; wheat
Abstract:
... 1 Adult wheat stem sawflies Cephus cinctus, pests of cultivated cereals that also infests wild grasses, migrate into wheat fields where they oviposit in elongating, succulent stems. 2 Volatiles released by wheat plants at susceptible stages were analyzed to determine potential semiochemical compounds. Seven major compounds were identified and quantified. 3 A Y-tube bioassay was developed to evalua ...
... The continuous aerobic degradation of phenol, mixed with readily degradable synthetic wastewater was studied over a period of 400 days at 25±5°C temperature in a fixed bed biofilm reactor using 'Liapor' clay beads as packing material. The phenol concentration added to the reactor ranged from 0.19 to 5.17g/l and was achieved by a gradual increase of phenol in wastewater, thus adapting the microbial ...
... Most of our understanding of the physiology of microorganisms is the result of investigations in pure culture. However, in order to understand complex environmental processes, there is a need to investigate mixed microbial communities. This is true for enhanced biological phosphorus removal (EBPR), an environmental process that results in the enrichment of the polyphosphate-accumulating organism A ...
... Biofilm formation and adherence properties of 13 bacterial strains commonly found in wastewater treatment systems were studied in pure and mixed cultures using a crystal violet microtiter plate assay. Four different culture media were used, wastewater, acetate medium, glucose medium and diluted nutrient broth. The medium composition strongly affected biofilm formation. All strains were able to for ...
... Biodegradation kinetic behaviors of ethyl acetate and amyl acetate in a composite bead biofilter were investigated. The composite bead was the spherical PVA/peat/KNO₃/GAC composite bead which was prepared in our previous works. Both microbial growth rate and biochemical reaction rate were inhibited at higher inlet concentration. For the microbial growth process, the microbial growth rate of ethyl ...
... The potential to produce and accumulate mono- and sesquiterpenes in lemon mint (Mentha aquatica var. citrata) glandular trichomes was evaluated. Volatiles were extracted using methyl-tert-butyl ether or solid phase micro extraction and determined by gas chromatography-mass spectrometry. The main components of the essential oil of lemon mint are the monoterpene alcohol linalool ...
... The effects of short-chain fatty acids (butyrate, propionate, and acetate) and trichostatin A (TSA), a typical histone deacetylase inhibitor, on tumor necrosis factor (TNF)-α secretion and nuclear factor κB (NF-κB) activation in peripheral blood mononuclear cells induced with lipopolysaccharide were evaluated in relation to prostaglandin E₂ (PGE₂) secretion. Treatment of cells with butyrate; tribu ...
... A pre-column derivatization method for sensitive determination of oligopeptides, using the tagging reagent 2-(9-carbazole)ethyl chloroformate (CEOC-Cl) followed by capillary electrophoresis (CE) with diode-array detection, has been developed. Maximum yield close to 100% were observed when a three to fourfold molar excess of reagent was used at pH 9.0–10.0. Excess reagent was extracted with n-hexan ...
... A macrocyclic polyamine, 1,5,9,13,17,21,25,29-octaazacyclodotriacontane ([32]ane-N₈), in the bonded phase was employed as a molecular receptor for CEC separation of oligopeptides. Parameters affecting the performance of the separations were considered. Baseline separation for the mixture of angiotensin I, angiotensin II, [Sar¹, Thr⁸]-angiotensin II, β-casomorphin bovine, β-casomorphin human, oxyto ...
... The ability of Pdᴵᴵ complexes derived from 2,6-pyridinedicarboxylic acids to catalyze homogeneous regioselective aerobic oxidation of 5- and 6-substituted 8-methylquinolines in AcOH–Ac₂O solution to produce corresponding 8-quinolylmethyl acetates in high yield was demonstrated; corresponding 8-quinoline carboxylic acids are minor reaction products. ...
acetates; bismuth; matrix-assisted laser desorption-ionization mass spectrometry; molecular weight; nuclear magnetic resonance spectroscopy; polymerization; polymers; salts
Abstract:
... Acidic bismuth salts, such as BiCl₃, BiBr₃, BiJ₃, and Bi-triflate catalyzed the ring-opening polymerization of 2-methoxazoline (MOZ) in bulk at 100 °C, whereas less acidic salts such as Bi₂O₃ or Bi(III)acetate did not. Bi-triflate-catalyzed polymerizations of 2-ethyloxazoline (EtOZ) were performed with variation of the monomer-catalyst ratio (M/C). It was found that the molecular weights were inde ...
... Many of the herbal extracts used in the Chinese clinical medical routine inhibit the growth of tumor cells. In the present work, extracts of 12 selected herbs were prepared with methanol, chloroform, ethyl acetate and water, and the effects of these on the multidrug resistance (MDR) and P-glycoprotein of mouse lymphoma cells transfected with the human mdr1 gene and on a human lung alveolar epithel ...
... The interaction of Cu²⁺ ions with the homopolymer poly(styrene sulfonic acid) (PSSH), as well as with the copolymers of maleic acid (MAc) with styrene sulfonic acid (SSH) or vinyl acetate (VAc), was investigated in dilute aqueous solution through turbidimetry, potentiometry, viscometry, and spectrophotometry in the visible region. Cu²⁺ ions were introduced either through neutralization with Cu(OH) ...
... Fungi are the dominant organisms decomposing leaf litter in streams and mediating energy transfer to other trophic levels. However, less is known about their role in decomposing submerged wood. This study provides the first estimates of fungal production on wood and compares the importance of fungi in the decomposition of submerged wood versus that of leaves at the ecosystem scale. We determined f ...
Archaea; Dendrosporobacter; acetates; bioreactors; chemical analysis; denaturing gradient gel electrophoresis; fermentation; methane production; methanogens; microbial communities; oligonucleotide probes; oxidation; population structure; propionic acid; sulfate-reducing bacteria; sulfates
Abstract:
... The microbial population structure and function of natural anaerobic communities maintained in lab-scale continuously stirred tank reactors at different lactate to sulfate ratios and in the absence of sulfate were analyzed using an integrated approach of molecular techniques and chemical analysis. The population structure, determined by denaturing gradient gel electrophoresis and by the use of oli ...
... Maternal hyperthermia induces pre-implantation embryo death, which is accompanied by enhanced physiological oxidative stress. We evaluated whether the administration of DL-α-tocopherol acetate (TA) to hyperthermic mothers mitigated pre-implantation embryo death. Mice were exposed to heat stress (35 °C, 60% relative humidity) for 12 h or not heated (25 °C) on the day of mating. Twelve hours before ...
acetates; animal models; chronic diseases; encephalitis; mechanism of action; mice; oligodendroglia; scanning electron microscopy; sclerosis; stem cells
Abstract:
... The interplay between demyelination and remyelination is critical in the progress of multiple sclerosis (MS) and its animal model, experimental autoimmune encephalomyelitis (EAE). In the present study, we explored the capacity of glatiramer acetate (GA, Copaxone) to affect the demyelination process and/or lead to remyelination in mice inflicted by chronic EAE, using both scanning electron microsco ...
... Extensive use of insecticides on cotton has prompted resistance development in the cotton aphid, Aphis gossypii (Glover) in China. A deltamethrin-selected population of cotton aphids from Xinjiang Uygur Autonomous Region, China with 228.59-fold higher resistance to deltamethrin was used to examine how carboxylesterase conferred resistance to this pyrethroid insecticide. The carboxylesterase activi ...
... Six strains of novel bacteria were isolated from profundal sediment of Lake Constance, a deep freshwater lake in Germany, by direct dilution of the sediment in mineral agar medium containing a background lawn of the hydrogen-scavenging Methanospirillum hungatei as a syntrophic partner. The numbers of colony-forming units obtained after incubation for more than 2 months were in the same range as th ...
... To investigate the ecophysiology of populations of polyphosphate-accumulating organisms (PAO) and glycogen-accumulating organisms (GAO) in communities of a novel acetate fed process removing phosphate from wastewater. Attempts were made to see if acetate could be replaced by an alternative carbon source which did not support the growth of the GAO. A continuously aerated sequencing batch reactor wa ...
... To elucidate the physiological adaptation of Escherichia coli due to cra gene knockout, a total of 3,911 gene expressions were investigated by DNA microarray for continuous culture. About 50 genes were differentially regulated for the cra mutant. TCA cycle and glyoxylate shunt were down-regulated, while pentose phosphate (PP) pathway and Entner Doudoroff (ED) pathway were up-regulated in the cra m ...
... The goal of this study was to examine the effect of feeding strategy on the capability for treatment and the stability of an anaerobic sequencing batch reactor (ASBR) under increasing organic loading. The lab-scale ASBR systems were operated at 35°C using synthetic organic wastewater under both batch and fed-batch operational modes with different feed to cycle time (F:C) ratios. Experimental studi ...
... Previously, we produced two groups of gnotobiotic mice, GB-3 and GB-4, which showed different responses to Escherichia coli O157:H7 challenge. E. coli O157:H7 was eliminated from GB-3, whereas GB-4 became carriers. In this study, we analysed the mechanisms of E. coli O157:H7 elimination using GB-3 and GB-4. When GB-3 and GB-4 mice were challenged with E. coli O157:H7, the E. coli O157:H7 populatio ...
... The effect of static magnetic field on the production of polyhydroxyalkanoates (PHAs) from different short-chain fatty acids by activated sludge process under aerobic dynamic feeding (ADF) technique was evaluated in four sequencing batch reactors (SBRs) with static magnetic field intensity of 42mT (SBR1), 21mT (SBR2), 7mT (SBR3), 0mT (SBR4), respectively. It was demonstrated that the static magnet ...
... The purpose of this study was to determine if moderate levels of carnosine supplement, alone or in combination with vitamin E, enhance antioxidant status and/or provide protection against oxidative stress. Fiftyfour one-month-old male Sprague-Dawley rats were fed a basal vitamin E-deficient diet supplemented with either 0, 200, or 1000 mg L-carnosine, and either 0, 10, or 100 IU vitamin E (as all ...
... This study was completed to investigate whether a fibrolytic enzyme preparation with xylanase and cellulase activities (Fibrozyme[trade mark sign], Alltech Inc., Nicholasville, KY, USA), could stimulate in vitro rumen fermentation of alfalfa hay, grass hay and barley straw, and their isolated cell walls as neutral detergent fibre (NDF). Samples (500mg) of each substrate were incubated in 120ml bot ...
... The aim of this study was to determine how evaporative cooling modifies body function with respect to water metabolism and other variables relevant to milk synthesis in crossbred cattle. The study was conducted on two groups of 0.875HF:0.125RS crossbred Holstein cattle (87.5%) housed in an open-sided barn with a tiled roof (non-cooled animals) and in a close-sided barn under an evaporative cooling ...
... Microbiological investigation of anaerobic ammonium oxidizing (anammox) bacteria has until now been restricted to wastewater species. The present study describes the enrichment and characterization of two marine Scalindua species, the anammox genus that dominates almost all natural habitats investigated so far. The species were enriched from a marine sediment in the Gullmar Fjord (Sweden) using a ...
... Although the effects of filler nanoparticles size and surface treatment on the glass transition temperature of the matrix phase have received well-deserved attention, nanofiller effects on other physical parameters associated with the glass transition have received less interest. To better understand how the incorporation of nanofillers affects the enthalpic relaxations associated with the glass t ...
... Alcohol acetyltransferase (AAT) catalyzing 2-phenylethyl alcohol and acetyl co-enzyme A (acetyl-CoA) to form phenylethyl acetate in Hanseniaspora valbyensis was studied. The enzyme was solubilized from lipid particles using 1% Triton X-100 and then purified by three steps of chromatographic separations with diethylaminoethlyl (DEAE) Sepharose, Sephadex G-75 and Octyl Sepharose, respectively. Its m ...
Ruditapes philippinarum; acetates; alizarin; juveniles; littoral zone
Abstract:
... The conventional acetate peel method was modified to analyze the shell growth pattern of juvenile Manila clam Ruditapes philippinarum as small as 2 mm in shell length (SL). In the outer shell layer along the axis of maximum growth, two types of growth increments were observed: distinct increments and indistinct increments, which, respectively, do and do not continue to the middle shell layer. The ...
... Esterases are a group of enzymes that are reportedly associated with acaricide resistance in Riphicephallus (Boophilus) microplus. A comparative analysis was made of the esterase patterns in malathion and deltamethrin-sensitive, tolerant and resistant tick groups, using non-denaturing polyacrylamide gel electrophoresis. Electrophoretical profiles revealed four bands of esterase activity against α- ...
... The glycoside hydrolase activity of Saccharomyces cerevisiae and Brettanomyces custersii was examined on sour cherry (Prunus cerasus L.) glycosides with bound volatile compounds. Refermentations by the β-glucosidase-negative S. cerevisiae strains LD25 and LD40 of sour cherry juice-supplemented beer demonstrated only a moderate increase of volatiles. In contrast, the β-glucosidase-positive B. custe ...