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Acetic Acid (acetic + acid)
Kinds of Acetic Acid Terms modified by Acetic Acid Selected AbstractsMAGNIFICATION ENDOSCOPIC VIEW OF AN EARLY GASTRIC CANCER USING ACETIC ACID AND NARROW-BAND IMAGING SYSTEMDIGESTIVE ENDOSCOPY, Issue 2006Hideki Toyoda A 62-year-old woman was referred to Mie University Hospital, Tsu, Japan, for examination of upper gastrointestinal tract. The conventional endoscopy showed a slightly depressed lesion on the greater curvature at the gastric body. The surface of surrounding non-neoplastic mucosa using magnification endoscopy with acetic acid was gyrus-villous pattern whereas the surface of the lesion was rough. Furthermore, magnification endoscopy using acetic acid and narrow-band imaging system visualized clearer fine surface pattern of carcinoma. The lesion had a rough mucosa with irregularly arranged small pits. The lesion was resected completely by endoscopic mucosal resection with insulated-tip electrosurgical knife. Narrow-band imaging system with acetic acid may be able to visualize not only the capillary pattern but also the fine surface pattern of gastric carcinoma. [source] CARBON SOURCES AND THEIR EFFECT ON GROWTH, ACETIC ACID AND ETHANOL PRODUCTION BY BRETTANOMYCES BRUXELLENSIS IN BATCH CULTUREJOURNAL OF FOOD PROCESS ENGINEERING, Issue 1 2007M.G. AGUILAR USCANGA ABSTRACT The influence of available low-cost carbohydrates as carbon sources on Brettanomyces bruxellensis growth, acetic acid and ethanol production was studied in order to ascertain the viability of this yeast to eventually become an industrial acetic acid producer. Six different raw materials were included as carbon sources (glucose, sugarcane molasses, refined cane sugar, pineapple, sugarcane and beet juices). B. bruxellensis develops in a complex culture medium like plant juices and sugarcane molasses better than in a medium with a simple carbohydrate such as glucose. The maximum acid acetic yield (0.24 g/g) and productivity (0.14 g/L/h) were attained in tests carried out with sugarcane molasses containing 60 g/L sucrose. The strain produced low levels of ethanol in a refined sugarcane medium, but was able to produce a substantial quantity of acetic acid (13 g/L). [source] Effect of Sodium Chloride, Acetic Acid, and Enzymes on Carotene Extraction in Carrots (Daucus carota L.)JOURNAL OF FOOD SCIENCE, Issue 2 2005Maria E. Jaramillo-Flores ABSTRACT: Carrot root cores were cut off longitudinally and treated with NaCl (0.6 and 1.2 M) and/or acetic acid (1.33%, 2.67%, and 4%) solutions. The extractability of the carotenes was estimated. Similarly, carrot cores were also treated with some degrading enzymes (carbohydrases, lipases, and proteases) alone or in combination to study the effect of the tissue rupture or the hydrolysis of possible complexes or interactions between carotenes and other components on the carotene extractability. The results showed that acetic acid increased the extractability of ,- and , carotenes up to 99.8% and 94.6%, respectively, at a 4% acid concentration compared with the samples without any treatment. This increase was directly proportional to the acid concentration. An increase in extractability was also observed for NaCl, although the increases were not as high as in the previous case with values of 49% and 41.4% for ,- and ,-carotenes respectively at a 0.6 M concentration. The study of microstructural changes and extractability revealed that the enzymatic treatments could have broken some carotene complexes and interactions and altered the carbohydrate matrix structure, increasing to a certain extent the extractability of carotenes. It can be concluded then that pickling with 4% acetic acid is a good method to increase the extractability of ,- and ,-carotenes. [source] Acetic Acid, Ethanol and Steam Effects on the Growth of Botrytis cinerea in vitro and Combination of Steam and Modified Atmosphere Packaging to Control Decay in KiwifruitJOURNAL OF PHYTOPATHOLOGY, Issue 2 2009Anastasia L. Lagopodi Abstract The effects of acetic acid fumigation, ethanol fumigation, and steam heat treatment on growth of Botrytis cinerea in vitro were investigated. The effect of steam heat treatments in combination with modified atmosphere packaging (MAP) on Botrytis decay development on ,Hayward' kiwifruit was also studied. The fungus was grown in Petri dishes on potato dextrose agar. Ethanol fumigation with 100 ,l/l for 3 or 6 min, or 200 ,l/l for 6 min enhanced the growth of B. cinerea. The effect of acetic acid on growth of B. cinerea was time and dosage-dependent. Fumigation with 1 ,l/l for 6 min, 2 ,l/l for 3 min, and 4 ,l/l for 3 min promoted radial growth of the fungus when compared to the growth of the untreated control. Fumigation with 2 ,l/l for 6 min delayed the growth of the fungus for the first 6 days, while fumigation with 6 ,l/l for 3 min delayed the growth of the fungus after the sixth day. Fumigation with 4 or 6 ,l/l acetic acid for 6 min, and 8 ,l/l acetic acid for 3 or 6 min resulted in complete inhibition of fungal growth. Steam heat treatment at 45°C for 6 min, and at 48, 51, and 54°C for 3 or 6 min completely inhibited fungal growth in vitro. Furthermore, steam treatments at 47, 50, and 53°C for 3 or 6 min completely inhibited decay at the stem end of kiwifruit kept at 10°C in MAP for 12 days. However, none of the steam treatments inhibited decay in wounds on the surface of the fruit kept in MAP. [source] Detection of Recent Ethanol Intake With New Markers: Comparison of Fatty Acid Ethyl Esters in Serum and of Ethyl Glucuronide and the Ratio of 5-Hydroxytryptophol to 5-Hydroxyindole Acetic Acid in UrineALCOHOLISM, Issue 5 2005K Borucki Background: At present, recent ethanol consumption can be routinely detected with certainty only by direct measurement of ethanol concentration in blood or urine. Because ethanol is rapidly eliminated from the circulation, however, the time span for this detection is in the range of hours. Several new markers have been proposed to extend the detection interval, but their characteristics have not yet justified their use in routine clinical practice. We therefore investigated three new markers and compared their kinetics and sensitivities: (1) fatty acid ethyl esters (FAEEs) in serum, (2) ethyl glucuronide (EtG) in urine, and (3) the ratio of 5-hydroxytryptophol to 5-hydroxyindole acetic acid (5-HTOL/5-HIAA) in urine. Methods: Seventeen healthy men participated in a drinking experiment. Blood and urine samples were collected twice daily on three consecutive days and once daily on days 4 and 5. Ethanol concentration was determined by gas chromatography, FAEE levels, by gas chromatography with mass spectrometry, EtG concentration, by liquid chromatography-tandem mass spectrometry, and 5-HTOL/5-HIAA ratio, by high-performance liquid chromatography. Results: The peak serum ethanol concentrations of the subjects ranged from 5.4 to 44.7 mmol/liter (mean ± SD, 30.1 ± 9.1 mmol/liter). In the case of the serum ethanol determination, 100% sensitivity was reached only immediately after the end of the drinking experiment, and in the case of FAEE levels and 5-HTOL/5-HIAA ratio, it tested for 6.7 hr after the end of the ethanol intake. Thereafter, these latter parameters declined until 15.3 hr (FAEEs) and 29.4 hr (5-HTOL/5-HIAA), subsequently remaining in a stable range until 78.5 hr without further decrease. In contrast, EtG concentration showed 100% sensitivity until 39.3 hr and thereafter decreased, falling to below the limit of quantification of 0.1 mg/liter at 102.5 hr. Conclusion: After moderate drinking, EtG in the urine proved to be a superior marker of recent ethanol consumption in healthy subjects. This is because EtG is a direct ethanol metabolite, it occurs in the urine only when ethanol has been consumed, and its sensitivity remains at the level of 100% for 39.3 hr. [source] Modeling and Biokinetics in Anaerobic Acidogenesis of Starch-Processing Wastewater to Acetic AcidBIOTECHNOLOGY PROGRESS, Issue 2 2004Johng-Hwa Ahn Starch-processing wastewater was anaerobically treated to produce acetic acid in laboratory-scale, continuously stirred tank reactors. The optimal conditions, in which the maximum acetic acid production occurred, were 0.56 d hydraulic retention time, pH 5.9, and 36.1 °C. Acetic acid production at the optimum conditions was 672 ± 20 mg total organic carbonequivalent L,1, which indicated a 75% conversion efficiency of influent total organic carbon into acetic acid. A fourth order Runge-Kutta approximation was used to determine the Monod kinetics of the acidogens by using unsteady-state data from continuous unsteady-state experiments at the optimum conditions. The model outputs and experimental data fit together satisfactorily, suggesting that the unsteady-state approach was appropriate for the evaluation of acidogenic biokinetics. These included ,m, Ks, Y, and kd, which were evaluated as being 0.13 h,1, 25 mg total carbohydrate (TC) L,1, 0.38 mg volatile suspended solid mg,1 TC, and 0.002 h,1, respectively. [source] ChemInform Abstract: Condensed Bridgehead Nitrogen Heterocyclic System: Synthesis and Pharmacological Activities of 1,2,4-Triazolo-[3,4-b]-1,3,5-thiadiazole Derivatives of Ibuprofen and Biphenyl-4-yloxy Acetic Acid.CHEMINFORM, Issue 28 2009Mohd. Amir Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: A Diastereoselective Route to 2,6-syn-Disubstituted Tetrahydropyrans: Synthesis of the Civet Compound (+)-2-((2S,6S)-6-Methyltetrahydro-2H-pyran-2-yl) Acetic Acid.CHEMINFORM, Issue 13 2009Matthew O'Brien Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Copper Methanesulfonate,Acetic Acid as a Novel Catalytic System for Tetrahydropyranylation of Alcohols and Phenols.CHEMINFORM, Issue 18 2008Min Wang Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Highly Regio- and Stereoselective Palladium(0)-Catalyzed Addition of Organoboronic Acids with 1,2-Allenic Sulfones, Sulfoxides, or Alkyl- or Aryl-Substituted Allenes in the Presence of Acetic Acid: An Efficient Synthesis of (E)-Alkenes.CHEMINFORM, Issue 52 2007Hao Guo Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Regioselective Control in the Palladium-Catalyzed Isomerization of Methylenecyclopropylcarbinols Using Acetic Acid as a Reagent.CHEMINFORM, Issue 32 2007Min Shi Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Palladium-Catalyzed Reactions of Vinylidenecyclopropanes with Acetic Acid.CHEMINFORM, Issue 1 2007Jian-Mei Lu Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Catalytic Aromatization of Hantzsch 1,4-Dihydropyridines by Ferric Perchlorate in Acetic Acid.CHEMINFORM, Issue 33 2005Majid M. Heravi Abstract For Abstract see ChemInform Abstract in Full Text. [source] Synthesis and Analgesic and Antiinflammatory Activity of Some New 6-Acyl-2-benzoxazolinone and 6-Acyl-2-benzothiazolinone Derivatives with Acetic Acid and Propanoic Acid Residues.CHEMINFORM, Issue 52 2003Serdar Uenlue Abstract For Abstract see ChemInform Abstract in Full Text. [source] Reduction of Diaryl Alkenes by Hypophosphorous Acid,Iodine in Acetic Acid.CHEMINFORM, Issue 41 2002Albert J. Fry Abstract For Abstract see ChemInform Abstract in Full Text. [source] ChemInform Abstract: A Convenient and Chemoselective Acetylation and Formylation of Alcohols and Phenols Using Acetic Acid and Ethyl Formate in the Presence of Bi(III) Salts.CHEMINFORM, Issue 2 2002Iraj Mohammadpoor-Baltork Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Effect of acetic acid and pH on the cofermentation of glucose and xylose to ethanol by a genetically engineered strain of Saccharomyces cerevisiaeFEMS YEAST RESEARCH, Issue 4 2010Elizabeth Casey Abstract A current challenge of the cellulosic ethanol industry is the effect of inhibitors present in biomass hydrolysates. Acetic acid is an example of one such inhibitor that is released during the pretreatment of hemicellulose. This study examined the effect of acetic acid on the cofermentation of glucose and xylose under controlled pH conditions by Saccharomyces cerevisiae 424A(LNH-ST), a genetically engineered industrial yeast strain. Acetic acid concentrations of 7.5 and 15 g L,1, representing the range of concentrations expected in actual biomass hydrolysates, were tested under controlled pH conditions of 5, 5.5, and 6. The presence of acetic acid in the fermentation media led to a significant decrease in the observed maximum cell biomass concentration. Glucose- and xylose-specific consumption rates decreased as the acetic acid concentration increased, with the inhibitory effect being more severe for xylose consumption. The ethanol production rates also decreased when acetic acid was present, but ethanol metabolic yields increased under the same conditions. The results also revealed that the inhibitory effect of acetic acid could be reduced by increasing media pH, thus confirming that the undissociated form of acetic acid is the inhibitory form of the molecule. [source] The influence of the acidic component of the gas-foaming porogen used in preparing an injectable porous calcium phosphate cement on its properties: Acetic acid versus citric acidJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 1 2008Saeed Hesaraki Abstract In the present study, macroporous calcium phosphate cements (CPCs) were prepared using a porogen; that is, the gas-foaming technique. The objective was to investigate the influence of the acidic component of the porogen (acetic acid versus citric acid) on several properties of a specified CPC. In all of the cements prepared, the basic component of the porogen was the same, namely, NaHCO3, and it was added to the powder phase of the cement, while the acidic component of the porogen was dissolved in the liquid phase of the cement. The cements were characterized in terms of initial setting time, porosity, crystallinity, injectability and compressive strength. Also, XRD, FTIR, and SEM techniques were employed to evaluate the phase composition, the chemical groups and the morphological aspects of the porous cements during setting. It was found that the presence of a porogen in a CPC led to significant decreases in both its initial setting time and compressive strength. A CPC made using acetic acid contained a larger amount of the apatite phase but was significantly less injectable and less porous than when citric acid was used. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2008 [source] Regioselective synthesis of 2-methyl-2,5,6,11,12,13-hexahydro 4H indazolo[5,4-a]pyrrolo[3,4-c]carbazole-4-onesJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 6 2009Ming Tao 2-Methyl-2,5,6,11,12,13-hexahydro 4H indazolo[5,4-a]pyrrolo[3,4-c]carbazole-4-one was synthesized utilizing a regioselective Diels-Alder reaction with 5-(1H-indol-2-yl)-2-methyl-6,7-dihydro-2H-indazole and ethyl cis -,-cyanoacrylate. Acetic acid and YtBr3 were the best solvent and catalyst for the regioselective Diels-Alder reaction. The chemistry was used to synthesize novel 8-pyrimidinyloxy-2,5,6,11,12,13-hexahydro 4H indazolo[5,4-a]pyrrolo[3,4-c]carbazole-4-ones that were screened and found to be potent inhibitors of DLK. J. Heterocyclic Chem., (2009). [source] Application of hydrophilic interaction chromatography retention coefficients for predicting peptide elution with TFA and methanesulfonic acid ion-pairing reagentsJOURNAL OF SEPARATION SCIENCE, JSS, Issue 6-7 2010Chad E. Wujcik Abstract Hydrophilic retention coefficients for 17 peptides were calculated based on retention coefficients previously published for TSKgel silica-60 and were compared with the experimental elution profile on a Waters Atlantis HILIC silica column using TFA and methanesulfonic acid (MSA) as ion-pairing reagents. Relative peptide retention could be accurately determined with both counter-ions. Peptide retention and chromatographic behavior were influenced by the percent acid modifier used with increases in both retention and peak symmetry observed at increasing modifier concentrations. The enhancement of net peptide polarity through MSA pairing shifted retention out by nearly five-fold for the earliest eluting peptide, compared with TFA. Despite improvements in retention and efficiency (Neff) for MSA over TFA, a consistent reduction in calculated selectivity (,) was observed. This result is believed to be attributed to the stronger polar contribution of MSA masking and diminishing the underlying influence of the amino acid residues of each associated peptide. Finally, post-column infusion of propionic acid and acetic acid was evaluated for their potential to recover signal intensity for TFA and MSA counter-ions for LC-ESI-MS applications. Acetic acid generally yielded more substantial signal improvements over propionic acid on the TFA system while minimal benefits and some further reductions were noted with MSA. [source] GC-MS and 13C NMR Investigation of Lead Zirconate Titanate Precursor Sols for Fiber PreparationJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 2 2007Mei Zhang Different macroscopic properties of PZT fibers have been obtained when using acetic acid and methacrylic acid to modify the PZT precursor. In order to clarify the role of the acids the molecular structure of the acidified PZT precursors was investigated and compared by gas chromatography-mass spectrometry, Fourier transform infrared, 13C nuclear magnetic resonance (NMR) spectroscopy (solution and solid state 13C NMR) and the reason for obtaining long PZT fibers is discussed. The results indicate that when methacrylic acid was used, long gel and ceramic fibers have been obtained because strongly co-ordinating carboxylate groups of methacrylic acid were formed. Linear chains, like those of methacrylic acid propyl ester and methacrylic acetate, have been formed in the PZT precursor sols. In addition, after heat treatment the polymer decomposed quickly so that pure perovskite could be obtained at low temperature in the PZT fibers. When acetic acid was used short fibers were obtained. Acetic acid may act as chelate agent to form oxo acetate in the precursors; this oxo acetate nature also resulted in PZT fibers drawing. However, the longest gel and ceramic fibers have been prepared from precursors with methacrylic acid. [source] Presence of sourdough lactic acid bacteria in commercial total mixed ration silage as revealed by denaturing gradient gel electrophoresis analysisLETTERS IN APPLIED MICROBIOLOGY, Issue 4 2010C. Wang Abstract Aims:, To characterize the bacterial communities in commercial total mixed ration (TMR) silage, which is known to have a long bunk life after silo opening. Methods and Results:, Samples were collected from four factories that produce TMR silage according to their own recipes. Three factories were sampled three times at 1-month intervals during the summer to characterize the differences between factories; one factory was sampled 12 times, three samples each during the summer, autumn, winter and spring, to determine seasonal changes. Bacterial communities were determined by culture-independent denaturing gradient gel electrophoresis. All silages contained lactic acid as the predominant acid, and the contents appeared stable regardless of factories and product seasons. Acetic acid and 1-propanol contents were different between factories and indicated seasonal changes, with increases in warm seasons compared to cool seasons. Both differences and similarities existed among the bacterial communities from each factory and product season. Lactobacillus parabuchneri was found in the products from three of four factories. Various sourdough lactic acid bacteria (LAB) were identified in commercial TMR silage; Lactobacillus panis, Lactobacillus hammesii, Lactobacillus mindensis, Lactobacillus pontis, Lactobacillus frumenti and Lactobacillus farciminis were detected in many products. Moreover, changes owing to product season were distinctive, and Lact. pontis and Lact. frumenti became detectable in summer products. Conclusion:, Sourdough LAB are involved in the ensiling of commercial TMR silage. Silage bacterial communities vary more by season than by factory. The LAB species Lact. parabuchneri was detected in the TMR silage but may not be essential to the product's long bunk life after silo opening. Significance and Impact of the Study:, Commercial TMR silage resembles sourdough with respect to bacterial communities and long shelf life. The roles of sourdough LAB in the ensiling process and aerobic stability are worth examining. [source] Cell-free supernatants of Escherichia coli Nissle 1917 modulate human colonic motility: evidence from an in vitro organ bath studyNEUROGASTROENTEROLOGY & MOTILITY, Issue 5 2009F. Bär Abstract, Clinical studies have shown that probiotics influence gastrointestinal motility, e.g. Escherichia coli Nissle 1917 (EcN) (Mutaflor®) proved to be at least as efficacious as lactulose and more potent than placebo in constipated patients. As the underlying mechanisms are not clarified, the effects of EcN culture supernatants on human colonic motility were assessed in vitro. Human colonic circular smooth muscle strips (n = 94, 17 patients) were isometrically examined in an organ bath and exposed to different concentrations of EcN supernatants. Contractility responses were recorded under (i) native conditions, (ii) electrical field stimulation (EFS), (iii) non-adrenergic non-cholinergic conditions, and (iv) enteric nerve blockade by tetrodotoxin (TTX). As concentrations of acetic acid were increased in EcN supernatants, contractility responses to acetic acid were additionally tested. EcN supernatants significantly increased the maximal tension forces both at low and high concentrations. Neither blockade of both adrenergic and cholinergic nerves nor application of TTX abolished these effects. EFS-induced contractility responses were not altered after exposure to EcN supernatants. Acetic acid elicited effects comparable to EcN supernatants only under TTX conditions. EcN supernatants modulate in vitro contractility of the human colon. As neither partial nor TTX blockade of enteric nerves abolished these effects, EcN supernatants appear to enhance colonic contractility by direct stimulation of smooth muscle cells. Active metabolites may include other substances than acetic acid, as acetic acid only partially resembled the effects elicited by EcN supernatants. The data provide a rationale for therapeutical application of probiotics in gastrointestinal motility disorders. [source] Nerve growth factor and gastric hyperalgesia in the ratNEUROGASTROENTEROLOGY & MOTILITY, Issue 4 2003K. Lamb Abstract We recently demonstrated an association between the development of hyperalgesia and an increase in nerve growth factor (NGF) during gastric inflammation. We hypothesized that block of NGF signalling will blunt injury-induced hyperalgesia. Male Sprague,Dawley rats (300,400 g) were anaesthetized, the stomach was exposed and placed in a circular clamp. Acetic acid (60%) or saline (control) was injected into this area and aspirated 45 s later, resulting in kissing ulcers. A balloon was surgically placed into the stomach and electromyographic responses to gastric distension (GD) were recorded from the acromiotrapezius muscle. Animals received a daily injection of neutralizing NGF antibody or control serum for 5 days. NGF in the stomach wall was measured with an ELISA. The severity of gastric injury was assessed macroscopically and by determination of myeloperoxidase (MPO) activity. Gastric injury enhanced the visceromotor response to GD and increased NGF content. Anti-NGF significantly blunted the development of hyperalgesia and led to a decrease in gastric wall thickness and MPO activity. Increases in NGF contribute to the development of hyperalgesia after gastric injury. This may be partly mediated by direct effects on afferent nerves and indirectly by modulatory effects on the inflammatory response. [source] Preparation and characterization of transparent PANI-SIO2 hybrid conducting filmsPOLYMER ENGINEERING & SCIENCE, Issue 5 2010Li Wei Dodecylbenzene sulfonic acid-doped polyaniline (DBSA-PANI) was prepared with 3-glycidoxypropyltrimethoxysilane (GPTMS) through a sol,gel route without water and ethanol. Acetic acid was used to play both the roles of reagent and catalyst during the hydrolysis-condensation reaction of GPTMS, which affected the structure of precursors. On the other hand, m -cresol can adjust the acidity of solution and it was also a secondary dopant in DBSA-PANI to enhance conductivity of hybrid films. The conductivity and visible light transmittance vary with the molar ratio of acetic acid to GPTMS and m -cresol to GPTMS. Sheet resistance of the new hybrid films made by a dipping process reaches 5.1 k,/, and visible light transmittance is higher than 75%. POLYM. ENG. SCI., 2010. © 2009 Society of Plastics Engineers [source] Performance and population analysis of a non-sterile trickle bed reactor inoculated with Caldicellulosiruptor saccharolyticus, a thermophilic hydrogen producerBIOTECHNOLOGY & BIOENGINEERING, Issue 5 2009J.W. van Groenestijn Abstract Non-axenic operation of a 400 L trickle bed reactor inoculated with the thermophile Caldicellulosiruptor saccharolyticus, yielded 2.8 mol,H2/mol hexose converted. The reactor was fed with a complex medium with sucrose as the main substrate, continuously flushed with nitrogen gas, and operated at 73°C. The volumetric productivity was 22 mmol,H2/(L,filterbed,h). Acetic acid and lactic acid were the main by-products in the liquid phase. Production of lactic acid occurred when hydrogen partial pressure was elevated above 2% and during suboptimal fermentation conditions that also resulted in the presence of mono- and disaccharides in the effluent. Methane production was negligible. The microbial community was analyzed at two different time points during operation. Initially, other species related to members of the genera Thermoanaerobacterium and Caldicellulosiruptor were present in the reactor. However, these were out-competed by C. saccharolyticus during a period when sucrose was completely used and no saccharides were discharged with the effluent. In general, the use of pure cultures in non-sterile industrial applications is known to be less useful because of contamination. However, our results show that the applied fermentation conditions resulted in a culture of a single dominant organism with excellent hydrogen production characteristics. Biotechnol. Bioeng. 2009;102: 1361,1367. © 2008 Wiley Periodicals, Inc. [source] ChemInform Abstract: Synthesis and Biological Evaluation of Amide Derivatives of (6-Chloro-2,3-dihydro-1H-inden-1-yl)acetic Acid as Potential Antiinflammatory Agents with Lower Gastrointestinal Toxicity.CHEMINFORM, Issue 43 2008Meenakshi Sharma Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Reaction of Hydrazide of (Tetrazol-5-yl)acetic Acid with Isothiocyanates and Antimicrobial Investigations of Newly-Obtained Compounds.CHEMINFORM, Issue 13 2008Monika Wujec Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: New Derivatives of 2-(3,5-Dioxo-4-azatricyclo [5.2.1.02,6-endo]dec-8-en-4-yl)acetic Acid.CHEMINFORM, Issue 10 2008Reactivity., Synthesis Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Reactions of {4-[Bis(2-chloroethyl)amino]phenyl}acetic Acid (Phenylacetic Acid Mustard) with 2,-DeoxyribonucleosidesCHEMISTRY & BIODIVERSITY, Issue 3 2007Diana Florea-Wang Abstract Phenylacetic acid mustard (PAM; 2), a major metabolite of the anticancer agent chlorambucil (CLB; 1), was allowed to react with 2,-deoxyadenosine (dA), 2,-deoxyguanosine (dG), 2,-deoxycytidine (dC), 2,-deoxy-5-methylcytidine (dMeC), and thymidine (T) at physiological pH (cacodylic acid, 50% base). The reactions were followed by HPLC and analyzed by HPLC/MS and/or 1H-NMR techniques. Although the predominant reaction observed was hydrolysis of PAM, 2 also reacted with various heteroatoms of the nucleosides to give a series of products: compounds 5,31. PAM (2) was found to be hydrolytically slightly more stable than CLB (1). The principal reaction sites of 2 with dA, dG, and with all pyrimidine nucleosides were N(1), N(7), and N(3), resp. Also, several other adducts were detected and characterized. There was no significant difference in the reactivity of 1 and 2 with dG, dA or T, but the N(3) dC,PAM adduct was deaminated easier than the corresponding CLB derivative. The role of PAM,2,-deoxyribonucleoside adducts on the cytotoxic and mutagenic properties of CLB (1) is discussed. [source] | |||||||||||||||||||||||||||||||||||||