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Sample records for acetic acid addition

  1. Okadaic acid: An additional non-phorbol-12-tetradecanoate-13-acetate-type tumor promoter

    SciTech Connect

    Suganuma, Masami; Fujiki, Hirota; Suguri, Hiroko; Yoshizawa, Shigeru; Hirota, Mitsuru; Nakayasu, Michie ); Ojika, Makoto; Wakamatsu, Kazumasa; Yamada, Kiyoyuki ); Sugimura, Takashi )

    1988-03-01

    Okadaic acid is a polyether compound of a C{sub 38} fatty acid, isolated from a black sponge, Halichondria okadai. Previous studies showed that okadaic acid is a skin irritant and induces ornithine decarboxylase in mouse skin 4 hr after its application to the skin. This induction was strongly inhibited by pretreatment of the skin with 13-cis-retinoic acid. A two-stage carcinogenesis experiment in mouse skin initiated by a single application of 100 {mu}g of 7,12-dimethylbenz(a)anthracene (DMBA) and followed by application of 10 {mu}g of okadaic acid twice a week revealed that okadaic acid is a potent additional tumor promoter: tumors developed in 93% of the mice treated with DMBA and okadaic acid by week 16. In contrast, tumors were found in only one mouse each in the groups treated with DMBA alone or okadaic acid alone. An average of 2.6 tumors per mouse was found in week 30 in the group treated with DMBA and okadaic acid. Unlike phorbol 12-tetradecanoate 13-acetate (TPA), teleocidin, and aplysiatoxin, okadaic acid did not inhibit the specific binding of ({sup 3}H)TPA to a mouse skin particulate fraction when added up to 100 {mu}M or activate calcium-activated, phospholipid-dependent protein kinase (protein kinase C) in vitro when added up to 1.2 {mu}M. Therefore, the actions of okadaic acid and phorbol ester may be mediated in different ways. These results show that okadaic acid is a non-TPA-type tumor promoter in mouse skin carcinogenesis.

  2. Antibiofilm Properties of Acetic Acid

    PubMed Central

    Bjarnsholt, Thomas; Alhede, Morten; Jensen, Peter Østrup; Nielsen, Anne K.; Johansen, Helle Krogh; Homøe, Preben; Høiby, Niels; Givskov, Michael; Kirketerp-Møller, Klaus

    2015-01-01

    Bacterial biofilms are known to be extremely tolerant toward antibiotics and other antimicrobial agents. These biofilms cause the persistence of chronic infections. Since antibiotics rarely resolve these infections, the only effective treatment of chronic infections is surgical removal of the infected implant, tissue, or organ and thereby the biofilm. Acetic acid is known for its antimicrobial effect on bacteria in general, but has never been thoroughly tested for its efficacy against bacterial biofilms. In this article, we describe complete eradication of both Gram-positive and Gram-negative biofilms using acetic acid both as a liquid and as a dry salt. In addition, we present our clinical experience of acetic acid treatment of chronic wounds. In conclusion, we here present the first comprehensive in vitro and in vivo testing of acetic acid against bacterial biofilms. PMID:26155378

  3. Enantioselective Synthesis of 1,2-Dihydronaphthalene-1-carbaldehydes by Addition of Boronates to Isochromene Acetals Catalyzed by Tartaric Acid

    PubMed Central

    Luan, Yi; Barbato, Keith S.; Moquist, Philip N.; Kodama, Tomohiro; Schaus, Scott E.

    2015-01-01

    Tartaric acid is an ideal asymmetric catalyst as it is abundant, cheap, and environmentally friendly. (+)-Tartaric acid was found to catalyze a novel enantioselective [4 + 2] cycloaddition of isochromene acetals and vinylboronates. A variety of substituted isochromene acetals were tolerated, furnishing the desired dihydronaphthalenes and dihydrobenzofluorene products in good yields. High enantiomeric ratios (up to 98.5:1.5) and excellent diastereoselectivities (all >99:1) were observed employing 10 mol % of (+)-tartaric acid as the catalyst, in combination with 5 mol % of Ho(OTf)3. PMID:25715172

  4. Lewis base activation of Lewis acids. Vinylogous aldol addition reactions of conjugated N,O-silyl ketene acetals to aldehydes.

    PubMed

    Denmark, Scott E; Heemstra, John R

    2006-02-01

    N,O-Silyl dienyl ketene acetals derived from unsaturated morpholine amides have been developed as highly useful reagents for vinylogous aldol addition reactions. In the presence of SiCl4 and the catalytic action of chiral phosphoramide (R,R)-3, N,O-silyl dienyl ketene acetal 8 undergoes high-yielding and highly site-selective addition to a wide variety of aldehydes with excellent enantioselectivity. Of particular note is the high yields and selectivities obtained from aliphatic aldehydes. Low catalyst loadings (2-5 mol %) can be employed. The morpholine amide serves as a useful precursor for further synthetic manipulation. PMID:16433495

  5. Electrospun homogeneous silk fibroin/poly (ɛ-caprolactone) nanofibrous scaffolds by addition of acetic acid for tissue engineering.

    PubMed

    Zhu, Jiang; Luo, Jingjing; Zhao, Xingyan; Gao, Junjiu; Xiong, Jie

    2016-09-01

    In this study, we investigated the phase separation phenomenon of silk fibroin/poly (ɛ-caprolactone) electrospinning solution to improve the performance of silk fibroin/poly (ɛ-caprolactone) electrospun nanofibers. It showed that phase separation does occur in just a few hours in the silk fibroin/poly (ɛ-caprolactone)/formic acid mixture solution. Acetic acid, small molecule nonsolvent for silk fibroin, was first introduced to silk fibroin/poly (ɛ-caprolactone)/formic acid solution, a homogeneous solution without separation for over several days was achieved after mixing for 5 h. The morphology and composition of the silk fibroin/poly (ɛ-caprolactone) and acetic acid-modified silk fibroin/poly (ɛ-caprolactone) fibrous scaffolds were examined by scanning electron microscopy, Fourier transform infrared spectroscopy and thermal gravimetric analyzer. Attachment and proliferation of mouse osteoblast MC3T3-E1 cells were tested by scanning electron microscopy and cytotoxity assay. The results indicated that the phase separation of silk fibroin/poly (ɛ-caprolactone) solution might led to inhomogeneous morphology and composition of the composite scaffolds, and the inhomogeneity of the silk fibroin/poly (ɛ-caprolactone) scaffolds with formic acid as solvent had a remarkable difference on cell adhesion and proliferation. In contrast, there was no significant difference among the silk fibroin/poly (ɛ-caprolactone) scaffolds with formic acid/acetic acid as solvent because of their good consistency in fiber morphology and composition. These obtained silk fibroin/poly (ɛ-caprolactone) nanofibers had small average diameter of 190 ± 40 nm. The obtained results proved that this study provided a facile and effective approach to achieve compositionally homogeneous silk fibroin/poly (ɛ-caprolactone) scaffolds with formic acid as solvent for effective applications. PMID:27422715

  6. Friedel-Crafts Fluoroacetylation of Indoles with Fluorinated Acetic Acids for the Synthesis of Fluoromethyl Indol-3-yl Ketones under Catalyst- and Additive-Free Conditions.

    PubMed

    Yao, Shun-Jiang; Ren, Zhi-Hui; Wang, Yao-Yu; Guan, Zheng-Hui

    2016-05-20

    A simple and efficient protocol for the fluoroacetylation of indoles is reported. The reaction uses fluorinated acetic acids as the fluoroacetylation reagents to synthesize diverse fluoromethyl indol-3-yl ketones in good yields under catalyst- and additive-free conditions. In addition, the only byproduct is water in this transformation. The synthetic utility of this reaction was also demonstrated by the concise synthesis of α-(trifluoromethyl)(indol-3-yl)methanol and indole-3-carboxylic acid. PMID:27101475

  7. Corrosion resistance of siloxane-poly(methyl methacrylate) hybrid films modified with acetic acid on tin plate substrates: Influence of tetraethoxysilane addition

    NASA Astrophysics Data System (ADS)

    Kunst, S. R.; Cardoso, H. R. P.; Oliveira, C. T.; Santana, J. A.; Sarmento, V. H. V.; Muller, I. L.; Malfatti, C. F.

    2014-04-01

    The aim of this paper is to study the corrosion resistance of hybrid films. Tin plate was coated with a siloxane-poly (methyl methacrylate) (PMMA) hybrid film prepared by sol-gel route with covalent bonds between the organic (PMMA) and inorganic (siloxane) phases obtained by hydrolysis and polycondensation of 3-(trimethoxysilylpropyl) methacrylate (TMSM) and polymerization of methyl methacrylate (MMA) using benzoyl peroxide (BPO) as a thermic initiator. Hydrolysis reactions were catalyzed by acetic acid solution avoiding the use of chlorine or stronger acids in the film preparation. The effect of the addition of tetraethoxysilane (TEOS) on the protective properties of the film was evaluated. The hydrophobicity of the film was determined by contact angle measurements, and the morphology was evaluated by scanning electron microscopy (SEM) and profilometry. The local nanostructure was investigated by Fourier transform infrared spectroscopy (FT-IR). The electrochemical behavior of the films was assessed by open circuit potential monitoring, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) measurements in a 0.05 M NaCl solution. The mechanical behavior was evaluated by tribology. The results highlighted that the siloxane-PMMA hybrid films modified with acetic acid are promising anti-corrosive coatings that acts as an efficient diffusion barrier, protecting tin plates against corrosion. However, the coating properties were affected by the TEOS addition, which contributed for the thickness increase and irregular surface coverage.

  8. 21 CFR 184.1005 - Acetic acid.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Acetic acid. 184.1005 Section 184.1005 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DIRECT FOOD....1005 Acetic acid. (a) Acetic acid (C2H4O2, CAS Reg. No. 64-19-7) is known as ethanoic acid. It...

  9. The impact of zinc sulfate addition on the dynamic metabolic profiling of Saccharomyces cerevisiae subjected to long term acetic acid stress treatment and identification of key metabolites involved in the antioxidant effect of zinc.

    PubMed

    Wan, Chun; Zhang, Mingming; Fang, Qing; Xiong, Liang; Zhao, Xinqing; Hasunuma, Tomohisa; Bai, Fengwu; Kondo, Akihiko

    2015-02-01

    The mechanisms of how zinc protects the cells against acetic acid toxicity and acts as an antioxidant are still not clear. Here we present results of the metabolic profiling of the eukaryotic model yeast species Saccharomyces cerevisiae subjected to long term high concentration acetic acid stress treatment in the presence and absence of zinc supplementation. Zinc addition decreased the release of reactive oxygen species (ROS) in the presence of chronic acetic acid stress. The dynamic changes in the accumulation of intermediates in central carbon metabolism were observed, and higher contents of intracellular alanine, valine and serine were observed by zinc supplementation. The most significant change was observed in alanine content, which is 3.51-fold of that of the control culture in cells in the stationary phase. Subsequently, it was found that 0.5 g L(-1) alanine addition resulted in faster glucose consumption in the presence of 5 g L(-1) acetic acid, and apparently decreased ROS accumulation in zinc-supplemented cells. This indicates that alanine exerted its antioxidant effect at least partially through the detoxification of acetic acid. In addition, intracellular glutathione (GSH) accumulation was enhanced by zinc addition, which is related to the protection of yeast cells from the oxidative injury caused by acetic acid. Our studies revealed for the first time that zinc modulates cellular amino acid metabolism and redox balance, especially biosynthesis of alanine and glutathione to exert its antioxidant effect. PMID:25554248

  10. 21 CFR 582.1005 - Acetic acid.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Acetic acid. 582.1005 Section 582.1005 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1005 Acetic acid. (a) Product. Acetic acid. (b) Conditions of use. This substance is...

  11. 21 CFR 582.1005 - Acetic acid.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Acetic acid. 582.1005 Section 582.1005 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1005 Acetic acid. (a) Product. Acetic acid. (b) Conditions of use. This substance is...

  12. 21 CFR 582.1005 - Acetic acid.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Acetic acid. 582.1005 Section 582.1005 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1005 Acetic acid. (a) Product. Acetic acid. (b) Conditions of use. This substance is...

  13. 21 CFR 582.1005 - Acetic acid.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Acetic acid. 582.1005 Section 582.1005 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1005 Acetic acid. (a) Product. Acetic acid. (b) Conditions of use. This substance is...

  14. 21 CFR 582.1005 - Acetic acid.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Acetic acid. 582.1005 Section 582.1005 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1005 Acetic acid. (a) Product. Acetic acid. (b) Conditions of use. This substance is...

  15. Sphingolipids contribute to acetic acid resistance in Zygosaccharomyces bailii.

    PubMed

    Lindahl, Lina; Genheden, Samuel; Eriksson, Leif A; Olsson, Lisbeth; Bettiga, Maurizio

    2016-04-01

    Lignocellulosic raw material plays a crucial role in the development of sustainable processes for the production of fuels and chemicals. Weak acids such as acetic acid and formic acid are troublesome inhibitors restricting efficient microbial conversion of the biomass to desired products. To improve our understanding of weak acid inhibition and to identify engineering strategies to reduce acetic acid toxicity, the highly acetic-acid-tolerant yeast Zygosaccharomyces bailii was studied. The impact of acetic acid membrane permeability on acetic acid tolerance in Z. bailii was investigated with particular focus on how the previously demonstrated high sphingolipid content in the plasma membrane influences acetic acid tolerance and membrane permeability. Through molecular dynamics simulations, we concluded that membranes with a high content of sphingolipids are thicker and more dense, increasing the free energy barrier for the permeation of acetic acid through the membrane. Z. bailii cultured with the drug myriocin, known to decrease cellular sphingo-lipid levels, exhibited significant growth inhibition in the presence of acetic acid, while growth in medium without acetic acid was unaffected by the myriocin addition. Furthermore, following an acetic acid pulse, the intracellular pH decreased more in myriocin-treated cells than in control cells. This indicates a higher inflow rate of acetic acid and confirms that the reduction in growth of cells cultured with myriocin in the medium with acetic acid was due to an increase in membrane permeability, thereby demonstrating the importance of a high fraction of sphingolipids in the membrane of Z. bailii to facilitate acetic acid resistance; a property potentially transferable to desired production organisms suffering from weak acid stress. PMID:26416641

  16. Extractive fermentation of acetic acid

    SciTech Connect

    Busche, R.M.

    1991-12-31

    In this technoeconomic evaluation of the manufacture of acetic acid by fermentation, the use of the bacterium: Acetobacter suboxydans from the old vinegar process was compared with expected performance of the newer Clostridium thermoaceticum bacterium. Both systems were projected to operate as immobilized cells in a continuous, fluidized bed bioreactor, using solvent extraction to recover the product. Acetobacter metabolizes ethanol aerobically to produce acid at 100 g/L in a low pH medium. This ensures that the product is in the form of a concentrated extractable free acid, rather than as an unextractable salt. Unfortunately, yields from glucose by way of the ethanol fermentation are poor, but near the biological limits of the organisms involved. Conversely, C. thermoaceticum is a thermophilic anaerobe that operates at high fermentation rates on glucose at neutral pH to produce acetate salts directly in substantially quantitative yields. However, it is severely inhibited by product, which restricts concentration to a dilute 20 g/L. An improved Acetobacter system operating with recycled cells at 50 g/L appears capable of producing acid at $0.38/lb, as compared with a $0.29/lb price for synthetic acid. However, this system has only a limited margin for process improvement. The present Clostridium system cannot compete, since the required selling price would be $0.42/lb. However, if the organism could be adapted to tolerate higher product concentrations at acid pH, selling price could be reduced to $0.22/lb, or about 80% of the price of synthetic acid.

  17. 21 CFR 184.1005 - Acetic acid.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Acetic acid. 184.1005 Section 184.1005 Food and... Substances Affirmed as GRAS § 184.1005 Acetic acid. (a) Acetic acid (C2H4O2, CAS Reg. No. 64-19-7) is known as ethanoic acid. It occurs naturally in plant and animal tissues. It is produced by fermentation...

  18. 21 CFR 184.1005 - Acetic acid.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Acetic acid. 184.1005 Section 184.1005 Food and... Substances Affirmed as GRAS § 184.1005 Acetic acid. (a) Acetic acid (C2H4O2, CAS Reg. No. 64-19-7) is known as ethanoic acid. It occurs naturally in plant and animal tissues. It is produced by fermentation...

  19. Experimental study of the hydrothermal reactivity of organic acids and acid anions: II. Acetic acid, acetate, and valeric acid

    NASA Astrophysics Data System (ADS)

    McCollom, Thomas M.; Seewald, Jeffrey S.

    2003-10-01

    Organic acids and acid anions occur in substantial concentrations in many aqueous geologic fluids and are thought to take part in a variety of geochemical processes ranging from the transport of metals in ore-forming fluids to the formation of natural gas to serving as a metabolic energy source for microbes in subsurface habitats. The widespread occurrence of organic acids and their potential role in diverse geologic processes has led to numerous experimental studies of their thermal stability, yet there remain substantial gaps in our knowledge of the factors that control the rates and reaction pathways for the decomposition of these compounds under geologic conditions. In order to address some of these uncertainties, a series of laboratory experiments were conducted to examine the behavior of organic acids and acid anions under hydrothermal conditions in the presence of minerals. Reported here are results of experiments where aqueous solutions of acetic acid, sodium acetate, or valeric acid ( n-pentanoic acid) were heated at 325°C, 350 bars in the presence of the mineral assemblages hematite + magnetite + pyrite, pyrite + pyrrhotite + magnetite, and hematite + magnetite. The results indicate that aqueous acetic acid and acetate decompose by a combination of two reaction pathways: decarboxylation and oxidation. Both reactions are promoted by minerals, with hematite catalyzing the oxidation reaction while magnetite catalyzes decarboxylation. The oxidation reaction is much faster, so that oxidation dominates the decomposition of acetic acid and acetate when hematite is present. In contrast to previous reports that acetate decomposed more slowly than acetic acid, we found that acetate decomposed at slightly faster rates than the acid in the presence of minerals. Although longer-chain monocarboxylic acids are generally thought to decompose by decarboxylation, valeric acid appeared to decompose primarily by "deformylation" to 1-butene plus formic acid. Subsequent

  20. Overview on mechanisms of acetic acid resistance in acetic acid bacteria.

    PubMed

    Wang, Bin; Shao, Yanchun; Chen, Fusheng

    2015-02-01

    Acetic acid bacteria (AAB) are a group of gram-negative or gram-variable bacteria which possess an obligate aerobic property with oxygen as the terminal electron acceptor, meanwhile transform ethanol and sugar to corresponding aldehydes, ketones and organic acids. Since the first genus Acetobacter of AAB was established in 1898, 16 AAB genera have been recorded so far. As the main producer of a world-wide condiment, vinegar, AAB have evolved an elegant adaptive system that enables them to survive and produce a high concentration of acetic acid. Some researches and reviews focused on mechanisms of acid resistance in enteric bacteria and made the mechanisms thoroughly understood, while a few investigations did in AAB. As the related technologies with proteome, transcriptome and genome were rapidly developed and applied to AAB research, some plausible mechanisms conferring acetic acid resistance in some AAB strains have been published. In this review, the related mechanisms of AAB against acetic acid with acetic acid assimilation, transportation systems, cell morphology and membrane compositions, adaptation response, and fermentation conditions will be described. Finally, a framework for future research for anti-acid AAB will be provided. PMID:25575804

  1. Simultaneous production of acetic and gluconic acids by a thermotolerant Acetobacter strain during acetous fermentation in a bioreactor.

    PubMed

    Mounir, Majid; Shafiei, Rasoul; Zarmehrkhorshid, Raziyeh; Hamouda, Allal; Ismaili Alaoui, Mustapha; Thonart, Philippe

    2016-02-01

    The activity of bacterial strains significantly influences the quality and the taste of vinegar. Previous studies of acetic acid bacteria have primarily focused on the ability of bacterial strains to produce high amounts of acetic acid. However, few studies have examined the production of gluconic acid during acetous fermentation at high temperatures. The production of vinegar at high temperatures by two strains of acetic acid bacteria isolated from apple and cactus fruits, namely AF01 and CV01, respectively, was evaluated in this study. The simultaneous production of gluconic and acetic acids was also examined in this study. Biochemical and molecular identification based on a 16s rDNA sequence analysis confirmed that these strains can be classified as Acetobacter pasteurianus. To assess the ability of the isolated strains to grow and produce acetic acid and gluconic acid at high temperatures, a semi-continuous fermentation was performed in a 20-L bioreactor. The two strains abundantly grew at a high temperature (41°C). At the end of the fermentation, the AF01 and CV01 strains yielded acetic acid concentrations of 7.64% (w/v) and 10.08% (w/v), respectively. Interestingly, CV01 was able to simultaneously produce acetic and gluconic acids during acetic fermentation, whereas AF01 mainly produced acetic acid. In addition, CV01 was less sensitive to ethanol depletion during semi-continuous fermentation. Finally, the enzymatic study showed that the two strains exhibited high ADH and ALDH enzyme activity at 38°C compared with the mesophilic reference strain LMG 1632, which was significantly susceptible to thermal inactivation. PMID:26253254

  2. Kinetics of Ethyl Acetate Synthesis Catalyzed by Acidic Resins

    ERIC Educational Resources Information Center

    Antunes, Bruno M.; Cardoso, Simao P.; Silva, Carlos M.; Portugal, Ines

    2011-01-01

    A low-cost experiment to carry out the second-order reversible reaction of acetic acid esterification with ethanol to produce ethyl acetate is presented to illustrate concepts of kinetics and reactor modeling. The reaction is performed in a batch reactor, and the acetic acid concentration is measured by acid-base titration versus time. The…

  3. Separating acetic acid from furol (furfural) by electrodialysis method

    SciTech Connect

    Guan, S.F.; Li, C.S. Ye, S.T.; Shen, S.Y.; Wang, Y.T.; Yu, S.H.

    1981-01-01

    Furfural production by hydrolysis of fibrous plant materials is accompanied by formation of acetic acid in amounts depending on the material used. The amount of acetic formed in the hydrolysis of the fruit shell of oil-tea camellia (Camellia oleosa) (an oilseed-bearing tree) is equal to the amount of furfural. The acetic acid can be separated from the furfural and concentrated to 10% by electrodialysis. A smaller amount of furfural is separated with acetic acid.

  4. [Degradation of oxytetracycline with ozonation in acetic acid solvent].

    PubMed

    Li, Shi-Yin; Li, Xiao-Rong; Zhu, Yi-Ping; Zhu, Jiang-Peng; Wang, Guo-Xiang

    2012-12-01

    Use acetic acid as the media of ozone degradation of oxytetracycline (OTC), and effects of the initial dosing ratio of ozone/OTC, ozone flow, free radical scavenger, metal ions on the removal rate of OTC were investigated respectively. The results showed that acetic acid had a high ozone stability and solubility. OTC had a high removal rate and degradation rate in acetic acid solution. With the increase of OTC dosage, the removal rate of OTC decreased in acetic acid. Removal rate of OTC was increased distinctly when ozone flow increased properly. It was also observed that free radical scavenger had a significantly negative effect on OTC ozonation degradation in acetic acid. Furthermore the main reactions of OTC ozone oxidation were direct oxidation and indirect oxidation in acetic acid. When Fe3+ and Co2+ were existent in acetic acid, the degradation of OTC was inhibited significantly. PMID:23379161

  5. Analysis of nine food additives in red wine by ion-suppression reversed-phase high-performance liquid chromatography using trifluoroacetic acid and ammonium acetate as ion-suppressors.

    PubMed

    Zhao, Yong-Gang; Chen, Xiao-Hong; Yao, Shan-Shan; Pan, Sheng-Dong; Li, Xiao-Ping; Jin, Mi-Cong

    2012-01-01

    A reversed-phase high-performance liquid chromatography (RP-HPLC) method was developed for the simultaneous determination of nine food additives, i.e., acesulfame, saccharin, caffeine, aspartame, benzoic acid, sorbic acid, stevioside, dehydroacetic acid and neotame in red wine. The effects of ion-suppressors, i.e., trifluoroacetic acid (TFA) and ammonium acetate (AmAc) on retention behavior of nine food additives in RP-HPLC separation were discussed in detail. The relationships between retention factors of solutes and volume percent of ion-suppressors in the mobile-phase systems of acetonitrile-TFA aqueous solution and acetonitrile-TFA-AmAc aqueous solution were quantitatively established, respectively. The results showed that the ion suppressors had not only an ion suppression effect, but also an organic modification effect on the acidic analytes. The baseline separation of nine food additives was completed by a gradient elution with acetonitrile-TFA(0.01%, v/v)-AmAc(2.5 mmol L(-1)) aqueous solution as the mobile phase. The recoveries were between 80.2 - 99.5% for all analytes with RSDs in the range of 1.5 - 8.9%. The linearities were in the range of 0.2 - 100.0 mg L(-1) with determination coefficients (r(2)) higher than 0.9991 for all analytes. The limits of quantification (LOQs) were between 0.53 - 0.99 mg L(-1). The applicability of the proposed method to detect and quantify food additives has been demonstrated in the analysis of 30 real samples. PMID:23059992

  6. Development of Acetic Acid Removal Technology for the UREX+Process

    SciTech Connect

    Robert M. Counce; Jack S. Watson

    2009-06-30

    It is imperative that acetic acid is removed from a waste stream in the UREX+process so that nitric acid can be recycled and possible interference with downstreatm steps can be avoidec. Acetic acid arises from acetohydrozamic acid (AHA), and is used to suppress plutonium in the first step of the UREX+process. Later, it is hydrolyzed into hydroxyl amine nitrate and acetic acid. Many common separation technologies were examined, and solvent extraction was determined to be the best choice under process conditions. Solvents already used in the UREX+ process were then tested to determine if they would be sufficient for the removal of acetic acid. The tributyl phosphage (TBP)-dodecane diluent, used in both UREX and NPEX, was determined to be a solvent system that gave sufficient distribution coefficients for acetic acid in addition to a high separation factor from nitric acid.

  7. Tested Demonstrations: Buffer Capacity of Various Acetic Acid-Sodium Acetate Systems: A Lecture Experiment.

    ERIC Educational Resources Information Center

    Donahue, Craig J.; Panek, Mary G.

    1985-01-01

    Background information and procedures are provided for a lecture experiment which uses indicators to illustrate the concept of differing buffer capacities by titrating acetic acid/sodium acetate buffers with 1.0 molar hydrochloric acid and 1.0 molar sodium hydroxide. A table with data used to plot the titration curve is included. (JN)

  8. Oxidation of indole-3-acetic acid to oxindole-3-acetic acid by an enzyme preparation from Zea mays

    NASA Technical Reports Server (NTRS)

    Reinecke, D. M.; Bandurski, R. S.

    1988-01-01

    Indole-3-acetic acid is oxidized to oxindole-3-acetic acid by Zea mays tissue extracts. Shoot, root, and endosperm tissues have enzyme activities of 1 to 10 picomoles per hour per milligram protein. The enzyme is heat labile, is soluble, and requires oxygen for activity. Cofactors of mixed function oxygenase, peroxidase, and intermolecular dioxygenase are not stimulatory to enzymic activity. A heat-stable, detergent-extractable component from corn enhances enzyme activity 6- to 10-fold. This is the first demonstration of the in vitro enzymic oxidation of indole-3-acetic acid to oxindole-3-acetic acid in higher plants.

  9. Improved Acetic Acid Resistance in Saccharomyces cerevisiae by Overexpression of the WHI2 Gene Identified through Inverse Metabolic Engineering.

    PubMed

    Chen, Yingying; Stabryla, Lisa; Wei, Na

    2016-01-01

    Development of acetic acid-resistant Saccharomyces cerevisiae is important for economically viable production of biofuels from lignocellulosic biomass, but the goal remains a critical challenge due to limited information on effective genetic perturbation targets for improving acetic acid resistance in the yeast. This study employed a genomic-library-based inverse metabolic engineering approach to successfully identify a novel gene target, WHI2 (encoding a cytoplasmatic globular scaffold protein), which elicited improved acetic acid resistance in S. cerevisiae. Overexpression of WHI2 significantly improved glucose and/or xylose fermentation under acetic acid stress in engineered yeast. The WHI2-overexpressing strain had 5-times-higher specific ethanol productivity than the control in glucose fermentation with acetic acid. Analysis of the expression of WHI2 gene products (including protein and transcript) determined that acetic acid induced endogenous expression of Whi2 in S. cerevisiae. Meanwhile, the whi2Δ mutant strain had substantially higher susceptibility to acetic acid than the wild type, suggesting the important role of Whi2 in the acetic acid response in S. cerevisiae. Additionally, overexpression of WHI2 and of a cognate phosphatase gene, PSR1, had a synergistic effect in improving acetic acid resistance, suggesting that Whi2 might function in combination with Psr1 to elicit the acetic acid resistance mechanism. These results improve our understanding of the yeast response to acetic acid stress and provide a new strategy to breed acetic acid-resistant yeast strains for renewable biofuel production. PMID:26826231

  10. Micelles Protect and Concentrate Activated Acetic Acid

    NASA Astrophysics Data System (ADS)

    Todd, Zoe; House, C.

    2014-01-01

    As more and more exoplanets are discovered and the habitability of such planets is considered, one can turn to searching for the origin of life on Earth in order to better understand what makes a habitable planet. Activated acetic acid, or methyl thioacetate, has been proposed to be central to the origin of life on Earth, and also as an important energy currency molecule in early cellular evolution. We have investigated the hydrolysis of methyl thioacetate under various conditions. Its uncatalyzed rate of hydrolysis is about three orders of magnitude faster (K = 0.00663 s^-1; 100°C, pH 7.5, concentration = 0.33mM) than published rates for its catalyzed production making it unlikely to accumulate under prebiotic conditions. However, we also observed that methyl thioacetate was protected from hydrolysis when inside its own hydrophobic droplets. We found that methyl thioacetate protection from hydrolysis was also possible in droplets of hexane and in the membranes of nonanoic acid micelles. Thus, the hydrophobic regions of prebiotic micelles and early cell membranes could have offered a refuge for this energetic molecule increasing its lifetime in close proximity to the reactions for which it would be needed. Methyl thioacetate could thus be important for the origin of life on Earth and perhaps for better understanding the potential habitability of other planets.

  11. Factors affecting acetic acid production by yeasts in strongly clarified grape musts.

    PubMed

    Moruno, E G; Delfini, C; Pessione, E; Giunta, C

    1993-01-01

    High acetate content in a wine, after strong clarification of the must, is due to depletion in the yeast cells of important metabolites (normally present in non-clarified musts) such as metals, amino acids, polyphenolic compounds and unsaturated fatty acids. These substances were added separately to a synthetic medium, comparable in composition to the clarified must, which was then inoculated with a high acetate producer strain. No effects were observed after the addition of various metals and amino acids. The addition of unsaturated fatty acids (Tween 80) caused a significant (p = 0.01) decrease in acetate content. Similar results have been obtained in the presence of polyphenols (catechins and anthocyans): their mechanism of action is probably due to direct inhibition of the enzyme aldehyde dehydrogenase. Control experiments were performed with a low acetate producer strain, and a reduction in acetate content was detected. No differences in the glyceropyruvic metabolism of the two strains was evident. PMID:8366831

  12. Biological Function of Acetic Acid-Improvement in Obesity and Glucose Tolerance by Acetic Acid in Type 2 Diabetic Rats.

    PubMed

    Yamashita, Hiromi

    2016-07-29

    Fatty acids derived from adipose tissue are oxidized by β-oxidation to form ketone bodies as final products under the starving condition. Previously, we found that free acetic acid was formed concomitantly with the production of ketone bodies in isolated rat liver perfusion, and mitochondrial acetyl CoA hydrolase was appeared to be involved with the acetic acid production. It was revealed that acetic acid was formed as a final product of enhanced β-oxidation of fatty acids and utilized as a fuel in extrahepatic tissues under the starving condition. Under the fed condition, β-oxidation is suppressed and acetic acid production is decreased. When acetic acid was taken daily by obesity-linked type 2 diabetic Otsuka Long-Evans Tokushima Fatty (OLETF) rats under the fed condition, it protected OLETF rats against obesity. Furthermore, acetic acid contributed to protect from the accumulation of lipid in the liver as well as abdominal fat in OLETF rats. Transcripts of lipogenic genes in the liver were decreased, while transcripts of myoglobin and Glut4 genes in abdominal muscles were increased in the acetic acid-administered OLETF rats. It is indicated that exogenously administered acetic acid would have effects on lipid metabolism in both the liver and the skeletal muscles, and have function that works against obesity and obesity-linked type 2 diabetes. PMID:26176799

  13. Glacial Acetic Acid Adverse Events: Case Reports and Review of the Literature

    PubMed Central

    Doles, William; Wilkerson, Garrett; Morrison, Samantha

    2015-01-01

    Glacial acetic acid is a dangerous chemical that has been associated with several adverse drug events involving patients over recent years. When diluted to the proper concentration, acetic acid solutions have a variety of medicinal uses. Unfortunately, despite warnings, the improper dilution of concentrated glacial acetic acid has resulted in severe burns and other related morbidities. We report on 2 additional case reports of adverse drug events involving glacial acetic acid as well as a review of the literature. A summary of published case reports is provided, including the intended and actual concentration of glacial acetic acid involved, the indication for use, degree of exposure, and resultant outcome. Strategies that have been recommended to improve patient safety are summarized within the context of the key elements of the medication use process. PMID:26448660

  14. A Binary Host Plant Volatile Lure Combined With Acetic Acid to Monitor Codling Moth (Lepidoptera: Tortricidae).

    PubMed

    Knight, A L; Basoalto, E; Katalin, J; El-Sayed, A M

    2015-10-01

    Field studies were conducted in the United States, Hungary, and New Zealand to evaluate the effectiveness of septa lures loaded with ethyl (E,Z)-2,4-decadienoate (pear ester) and (E)-4,8-dimethyl-1,3,7-nonatriene (nonatriene) alone and in combination with an acetic acid co-lure for both sexes of codling moth, Cydia pomonella (L.). Additional studies were conducted to evaluate these host plant volatiles and acetic acid in combination with the sex pheromone, (E,E)-8,10-dodecadien-1-ol (codlemone). Traps baited with pear ester/nonatriene + acetic acid placed within orchards treated either with codlemone dispensers or left untreated caught significantly more males, females, and total moths than similar traps baited with pear ester + acetic acid in some assays. Similarly, traps baited with codlemone/pear ester/nonatriene + acetic acid caught significantly greater numbers of moths than traps with codlemone/pear ester + acetic acid lures in some assays in orchards treated with combinational dispensers (dispensers loaded with codlemone/pear ester). These data suggest that monitoring of codling moth can be marginally improved in orchards under variable management plans using a binary host plant volatile lure in combination with codlemone and acetic acid. These results are likely to be most significant in orchards treated with combinational dispensers. Significant increases in the catch of female codling moths in traps with the binary host plant volatile blend plus acetic acid should be useful in developing more effective mass trapping strategies. PMID:26314018

  15. Fermentation of lignocellulosic sugars to acetic acid by Moorella thermoacetica.

    PubMed

    Ehsanipour, Mandana; Suko, Azra Vajzovic; Bura, Renata

    2016-06-01

    A systematic study of bioconversion of lignocellulosic sugars to acetic acid by Moorella thermoacetica (strain ATCC 39073) was conducted. Four different water-soluble fractions (hydrolysates) obtained after steam pretreatment of lignocellulosic biomass were selected and fermented to acetic acid in batch fermentations. M. thermoacetica can effectively ferment xylose and glucose in hydrolysates from wheat straw, forest residues, switchgrass, and sugarcane straw to acetic acid. Xylose and glucose were completely utilized, with xylose being consumed first. M. thermoacetica consumed up to 62 % of arabinose, 49 % galactose and 66 % of mannose within 72 h of fermentation in the mixture of lignocellulosic sugars. The highest acetic acid yield was obtained from sugarcane straw hydrolysate, with 71 % of theoretical yield based on total sugars (17 g/L acetic acid from 24 g/L total sugars). The lowest acetic acid yield was observed in forest residues hydrolysate, with 39 % of theoretical yield based on total sugars (18 g/L acetic acid from 49 g/L total sugars). Process derived compounds from steam explosion pretreatment, including 5-hydroxymethylfurfural (0.4 g/L), furfural (0.1 g/L) and total phenolics (3 g/L), did not inhibit microbial growth and acetic acid production yield. This research identified two major factors that adversely affected acetic acid yield in all hydrolysates, especially in forest residues: (i) glucose to xylose ratio and (ii) incomplete consumption of arabinose, galactose and mannose. For efficient bioconversion of lignocellulosic sugars to acetic acid, it is imperative to have an appropriate balance of sugars in a hydrolysate. Hence, the choice of lignocellulosic biomass and steam pretreatment design are fundamental steps for the industrial application of this process. PMID:26992903

  16. Measurement of the rates of oxindole-3-acetic acid turnover, and indole-3-acetic acid oxidation in Zea mays seedlings

    NASA Technical Reports Server (NTRS)

    Nonhebel, H. M.; Bandurski, R. S. (Principal Investigator)

    1986-01-01

    Oxindole-3-acetic acid is the principal catabolite of indole-3-acetic acid in Zea mays seedlings. In this paper measurements of the turnover of oxindole-3-acetic acid are presented and used to calculate the rate of indole-3-acetic acid oxidation. [3H]Oxindole-3-acetic acid was applied to the endosperm of Zea mays seedlings and allowed to equilibrate for 24 h before the start of the experiment. The subsequent decrease in its specific activity was used to calculate the turnover rate. The average half-life of oxindole-3-acetic acid in the shoots was found to be 30 h while that in the kernels had an average half-life of 35h. Using previously published values of the pool sizes of oxindole-3-acetic acid in shoots and kernels from seedlings of the same age and variety, and grown under the same conditions, the rate of indole-3-acetic acid oxidation was calculated to be 1.1 pmol plant-1 h-1 in the shoots and 7.1 pmol plant-1 h-1 in the kernels.

  17. Oxidation of indole-3-acetic acid and oxindole-3-acetic acid to 2,3-dihydro-7-hydroxy-2-oxo-1H indole-3-acetic acid-7'-O-beta-D-glucopyranoside in Zea mays seedlings

    NASA Technical Reports Server (NTRS)

    Nonhebel, H. M.; Bandurski, R. S.

    1984-01-01

    Radiolabeled oxindole-3-acetic acid was metabolized by roots, shoots, and caryopses of dark grown Zea mays seedlings to 2,3-dihydro-7-hydroxy-2-oxo-1H indole-3-acetic acid-7'-O-beta-D-glycopyranoside with the simpler name of 7-hydroxyoxindole-3-acetic acid-glucoside. This compound was also formed from labeled indole-3-acetic acid supplied to intact seedlings and root segments. The glucoside of 7-hydroxyoxindole-3-acetic acid was also isolated as an endogenous compound in the caryopses and shoots of 4-day-old seedlings. It accumulates to a level of 4.8 nanomoles per plant in the kernel, more than 10 times the amount of oxindole-3-acetic acid. In the shoot it is present at levels comparable to that of oxindole-3-acetic acid and indole-3-acetic acid (62 picomoles per shoot). We conclude that 7-hydroxyoxindole-3-acetic acid-glucoside is a natural metabolite of indole-3-acetic acid in Z. mays seedlings. From the data presented in this paper and in previous work, we propose the following route as the principal catabolic pathway for indole-3-acetic acid in Zea seedlings: Indole-3-acetic acid --> Oxindole-3-acetic acid --> 7-Hydroxyoxindole-3-acetic acid --> 7-Hydroxyoxindole-3-acetic acid-glucoside.

  18. Synthesis of acid addition salt of delta-aminolevulinic acid from 5-bromo levulinic acid esters

    DOEpatents

    Moens, Luc

    2003-06-24

    A process of preparing an acid addition salt of delta-aminolevulinc acid comprising: a) dissolving a lower alkyl 5-bromolevulinate and hexamethylenetetramine in a solvent selected from the group consisting of water, ethyl acetate, chloroform, acetone, ethanol, tetrahydrofuran and acetonitrile, to form a quaternary ammonium salt of the lower alkyl 5-bromolevulinate; and b) hydrolyzing the quaternary ammonium salt with an inorganic acid to form an acid addition salt of delta-aminolevulinic acid.

  19. Computerized image analysis for acetic acid induced intraepithelial lesions

    NASA Astrophysics Data System (ADS)

    Li, Wenjing; Ferris, Daron G.; Lieberman, Rich W.

    2008-03-01

    Cervical Intraepithelial Neoplasia (CIN) exhibits certain morphologic features that can be identified during a visual inspection exam. Immature and dysphasic cervical squamous epithelium turns white after application of acetic acid during the exam. The whitening process occurs visually over several minutes and subjectively discriminates between dysphasic and normal tissue. Digital imaging technologies allow us to assist the physician analyzing the acetic acid induced lesions (acetowhite region) in a fully automatic way. This paper reports a study designed to measure multiple parameters of the acetowhitening process from two images captured with a digital colposcope. One image is captured before the acetic acid application, and the other is captured after the acetic acid application. The spatial change of the acetowhitening is extracted using color and texture information in the post acetic acid image; the temporal change is extracted from the intensity and color changes between the post acetic acid and pre acetic acid images with an automatic alignment. The imaging and data analysis system has been evaluated with a total of 99 human subjects and demonstrate its potential to screening underserved women where access to skilled colposcopists is limited.

  20. Biosynthesis of the halogenated auxin, 4-chloroindole-3-acetic acid.

    PubMed

    Tivendale, Nathan D; Davidson, Sandra E; Davies, Noel W; Smith, Jason A; Dalmais, Marion; Bendahmane, Abdelhafid I; Quittenden, Laura J; Sutton, Lily; Bala, Raj K; Le Signor, Christine; Thompson, Richard; Horne, James; Reid, James B; Ross, John J

    2012-07-01

    Seeds of several agriculturally important legumes are rich sources of the only halogenated plant hormone, 4-chloroindole-3-acetic acid. However, the biosynthesis of this auxin is poorly understood. Here, we show that in pea (Pisum sativum) seeds, 4-chloroindole-3-acetic acid is synthesized via the novel intermediate 4-chloroindole-3-pyruvic acid, which is produced from 4-chlorotryptophan by two aminotransferases, TRYPTOPHAN AMINOTRANSFERASE RELATED1 and TRYPTOPHAN AMINOTRANSFERASE RELATED2. We characterize a tar2 mutant, obtained by Targeting Induced Local Lesions in Genomes, the seeds of which contain dramatically reduced 4-chloroindole-3-acetic acid levels as they mature. We also show that the widespread auxin, indole-3-acetic acid, is synthesized by a parallel pathway in pea. PMID:22573801

  1. Scaleable production and separation of fermentation-derived acetic acid. Final CRADA report.

    SciTech Connect

    Snyder, S. W.; Energy Systems

    2010-02-08

    ) Moderate ammonia flux. The advantages of producing acetic acid by fermentation include its appropriateness for small-scale production, lower cost feedstocks, low energy membrane-based purification, and lower temperature and pressure requirements. Potential energy savings of using fermentation are estimated to be approximately 14 trillion Btu by 2020 from a reduction in natural gas use. Decreased transportation needs with regional plants will eliminate approximately 200 million gallons of diesel consumption, for combined savings of 45 trillion Btu. If the fermentation process captures new acetic acid production, savings could include an additional 5 trillion Btu from production and 7 trillion Btu from transportation energy.

  2. Acetic acid oxidation and hydrolysis in supercritical water

    SciTech Connect

    Meyer, J.C.; Marrone, P.A.; Tester, J.W.

    1995-09-01

    Acetic acid (CH{sub 3}COOH) hydrolysis and oxidation in supercritical water were examined from 425--600 C and 246 bar at reactor residence times of 4.4 to 9.8 s. Over the range of conditions studied, acetic acid oxidation was globally 0.72 {+-} 0.15 order in acetic acid and 0.27 {+-} 0.15 order in oxygen to a 95% confidence level, with an activation energy of 168 {+-} 21 kJ/mol, a preexponential factor of 10{sup 9.9{+-}1.7}, and an induction time of about 1.5 s at 525 C. Isothermal kinetic measurements at 550 C over the range 160 to 263 bar indicated that pressure or density did not affect the rate of acetic acid oxidation as much as was previously observed in the oxidation of hydrogen or carbon monoxide in supercritical water. Major products of acetic acid oxidation in supercritical water are carbon dioxide, carbon monoxide, methane, and hydrogen. Trace amounts of propenoic acid were occasionally detected. Hydrolysis or hydrothermolysis in the absence of oxygen resulted in approximately 35% conversion of acetic acid at 600 C, 246 bar, and 8-s reactor residence time. Regression of the limited hydrolysis runs assuming a reaction rate first-order in organic gave a global rate expression with a preexponential factor of 10{sup 4.4{+-}1.1} and an activation energy of 94 {+-} 17 kJ/mol.

  3. Genetic dissection of acetic acid tolerance in Saccharomyces cerevisiae.

    PubMed

    Geng, Peng; Xiao, Yin; Hu, Yun; Sun, Haiye; Xue, Wei; Zhang, Liang; Shi, Gui-Yang

    2016-09-01

    Dissection of the hereditary architecture underlying Saccharomyces cerevisiae tolerance to acetic acid is essential for ethanol fermentation. In this work, a genomics approach was used to dissect hereditary variations in acetic acid tolerance between two phenotypically different strains. A total of 160 segregants derived from these two strains were obtained. Phenotypic analysis indicated that the acetic acid tolerance displayed a normal distribution in these segregants, and suggested that the acetic acid tolerant traits were controlled by multiple quantitative trait loci (QTLs). Thus, 220 SSR markers covering the whole genome were used to detect QTLs of acetic acid tolerant traits. As a result, three QTLs were located on chromosomes 9, 12, and 16, respectively, which explained 38.8-65.9 % of the range of phenotypic variation. Furthermore, twelve genes of the candidates fell into the three QTL regions by integrating the QTL analysis with candidates of acetic acid tolerant genes. These results provided a novel avenue to obtain more robust strains. PMID:27430512

  4. Tetrazole acetic acid: Tautomers, conformers, and isomerization

    NASA Astrophysics Data System (ADS)

    Araujo-Andrade, C.; Reva, I.; Fausto, R.

    2014-02-01

    Monomers of (tetrazol-5-yl)-acetic acid (TAA) were obtained by sublimation of the crystalline compound and the resulting vapors were isolated in cryogenic nitrogen matrices at 13 K. The conformational and tautomeric composition of TAA in the matrix was characterized by infrared spectroscopy and vibrational calculations carried out at the B3LYP/6-311++G(d,p) level. TAA may adopt two tautomeric modifications, 1H- and 2H-, depending on the position of the annular hydrogen atom. Two-dimensional potential energy surfaces (PESs) of TAA were theoretically calculated at the MP2/6-311++G(d,p) level, for each tautomer. Four and six symmetry-unique minima were located on these PESs, for 1H- and 2H-TAA, respectively. The energetics of the detected minima was subsequently refined by calculations at the QCISD level. Two 1H- and three 2H-conformers fall within the 0-8 kJ mol-1 energy range and should be appreciably populated at the sublimation temperature (˜330 K). Observation of only one conformer for each tautomer (1ccc and 2pcc) is explained in terms of calculated barriers to conformational rearrangements. All conformers with the cis O=COH moiety are separated by low barriers (less than 10 kJ mol-1) and collapse to the most stable 1ccc (1H-) and 2pcc (2H-) forms during deposition of the matrix. On the trans O=COH surfaces, the relative energies are very high (between 12 and 27 kJ mol-1). The trans forms are not thermally populated at the sublimation conditions and were not detected in matrices. One high-energy form in each tautomer, 1cct (1H-) and 2pct (2H-), was found to differ from the most stable form only by rotation of the OH group and separated from other forms by high barriers. This opened a perspective for their stabilization in a matrix. 1cct and 2pct were generated in the matrices selectively by means of narrow-band near-infrared (NIR) irradiations of the samples at 6920 and 6937 cm-1, where the first OH stretching overtone vibrations of 1ccc and 2pcc occur. The

  5. Tetrazole acetic acid: tautomers, conformers, and isomerization.

    PubMed

    Araujo-Andrade, C; Reva, I; Fausto, R

    2014-02-14

    Monomers of (tetrazol-5-yl)-acetic acid (TAA) were obtained by sublimation of the crystalline compound and the resulting vapors were isolated in cryogenic nitrogen matrices at 13 K. The conformational and tautomeric composition of TAA in the matrix was characterized by infrared spectroscopy and vibrational calculations carried out at the B3LYP/6-311++G(d,p) level. TAA may adopt two tautomeric modifications, 1H- and 2H-, depending on the position of the annular hydrogen atom. Two-dimensional potential energy surfaces (PESs) of TAA were theoretically calculated at the MP2/6-311++G(d,p) level, for each tautomer. Four and six symmetry-unique minima were located on these PESs, for 1H- and 2H-TAA, respectively. The energetics of the detected minima was subsequently refined by calculations at the QCISD level. Two 1H- and three 2H-conformers fall within the 0-8 kJ mol(-1) energy range and should be appreciably populated at the sublimation temperature (∼330 K). Observation of only one conformer for each tautomer (1ccc and 2pcc) is explained in terms of calculated barriers to conformational rearrangements. All conformers with the cis O=COH moiety are separated by low barriers (less than 10 kJ mol(-1)) and collapse to the most stable 1ccc (1H-) and 2pcc (2H-) forms during deposition of the matrix. On the trans O=COH surfaces, the relative energies are very high (between 12 and 27 kJ mol(-1)). The trans forms are not thermally populated at the sublimation conditions and were not detected in matrices. One high-energy form in each tautomer, 1cct (1H-) and 2pct (2H-), was found to differ from the most stable form only by rotation of the OH group and separated from other forms by high barriers. This opened a perspective for their stabilization in a matrix. 1cct and 2pct were generated in the matrices selectively by means of narrow-band near-infrared (NIR) irradiations of the samples at 6920 and 6937 cm(-1), where the first OH stretching overtone vibrations of 1ccc and 2pcc occur

  6. Tetrazole acetic acid: Tautomers, conformers, and isomerization

    SciTech Connect

    Araujo-Andrade, C.; Reva, I. Fausto, R.

    2014-02-14

    Monomers of (tetrazol-5-yl)-acetic acid (TAA) were obtained by sublimation of the crystalline compound and the resulting vapors were isolated in cryogenic nitrogen matrices at 13 K. The conformational and tautomeric composition of TAA in the matrix was characterized by infrared spectroscopy and vibrational calculations carried out at the B3LYP/6-311++G(d,p) level. TAA may adopt two tautomeric modifications, 1H- and 2H-, depending on the position of the annular hydrogen atom. Two-dimensional potential energy surfaces (PESs) of TAA were theoretically calculated at the MP2/6-311++G(d,p) level, for each tautomer. Four and six symmetry-unique minima were located on these PESs, for 1H- and 2H-TAA, respectively. The energetics of the detected minima was subsequently refined by calculations at the QCISD level. Two 1H- and three 2H-conformers fall within the 0–8 kJ mol{sup −1} energy range and should be appreciably populated at the sublimation temperature (∼330 K). Observation of only one conformer for each tautomer (1ccc and 2pcc) is explained in terms of calculated barriers to conformational rearrangements. All conformers with the cis O=COH moiety are separated by low barriers (less than 10 kJ mol{sup −1}) and collapse to the most stable 1ccc (1H-) and 2pcc (2H-) forms during deposition of the matrix. On the trans O=COH surfaces, the relative energies are very high (between 12 and 27 kJ mol{sup −1}). The trans forms are not thermally populated at the sublimation conditions and were not detected in matrices. One high-energy form in each tautomer, 1cct (1H-) and 2pct (2H-), was found to differ from the most stable form only by rotation of the OH group and separated from other forms by high barriers. This opened a perspective for their stabilization in a matrix. 1cct and 2pct were generated in the matrices selectively by means of narrow-band near-infrared (NIR) irradiations of the samples at 6920 and 6937 cm{sup −1}, where the first OH stretching overtone

  7. Acetic acid removal from corn stover hydrolysate using ethyl acetate and the impact on Saccharomyces cerevisiae bioethanol fermentation.

    PubMed

    Aghazadeh, Mahdieh; Ladisch, Michael R; Engelberth, Abigail S

    2016-07-01

    Acetic acid is introduced into cellulose conversion processes as a consequence of composition of lignocellulose feedstocks, causing significant inhibition of adapted, genetically modified and wild-type S. cerevisiae in bioethanol fermentation. While adaptation or modification of yeast may reduce inhibition, the most effective approach is to remove the acetic acid prior to fermentation. This work addresses liquid-liquid extraction of acetic acid from biomass hydrolysate through a pathway that mitigates acetic acid inhibition while avoiding the negative effects of the extractant, which itself may exhibit inhibition. Candidate solvents were selected using simulation results from Aspen Plus™, based on their ability to extract acetic acid which was confirmed by experimentation. All solvents showed varying degrees of toxicity toward yeast, but the relative volatility of ethyl acetate enabled its use as simple vacuum evaporation could reduce small concentrations of aqueous ethyl acetate to minimally inhibitory levels. The toxicity threshold of ethyl acetate, in the presence of acetic acid, was found to be 10 g L(-1) . The fermentation was enhanced by extracting 90% of the acetic acid using ethyl acetate, followed by vacuum evaporation to remove 88% removal of residual ethyl acetate along with 10% of the broth. NRRL Y-1546 yeast was used to demonstrate a 13% increase in concentration, 14% in ethanol specific production rate, and 11% ethanol yield. This study demonstrated that extraction of acetic acid with ethyl acetate followed by evaporative removal of ethyl acetate from the raffinate phase has potential to significantly enhance ethanol fermentation in a corn stover bioethanol facility. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:929-937, 2016. PMID:27090191

  8. Catalysis of the Carbonylation of Alcohols to Carboxylic Acids Including Acetic Acid Synthesis from Methanol.

    ERIC Educational Resources Information Center

    Forster, Denis; DeKleva, Thomas W.

    1986-01-01

    Monsanto's highly successful synthesis of acetic acid from methanol and carbon monoxide illustrates use of new starting materials to replace pretroleum-derived ethylene. Outlines the fundamental aspects of the acetic acid process and suggests ways of extending the synthesis to higher carboxylic acids. (JN)

  9. Absorption cross section for the 5νOH stretch of acetic acid and peracetic acid

    NASA Astrophysics Data System (ADS)

    Begashaw, I. G.; Collingwood, M.; Bililign, S.

    2009-12-01

    We report measurements of the absorption cross sections for the vibrational O-H stretch (5νOH) overtone transitions in glacial acetic acid and peracetic acid. The photochemistry that results from overtone excitation has been shown to lead to OH radical production in molecules containing O-H (HNO3, H2O2). In addition the overtone excitation has been observed to result in light initiated chemical reaction. A Cavity ring-down spectroscopy (CRDS) instrument comprising of an Nd:YAG pumped dye laser and 620nm high reflectivity mirrors (R=99.995%) was used to measure the cross sections. The dye laser wavelength was calibrated using water vapor spectrum and the HITRAN 2008 database. The instrument’s minimum detectable absorption is αmin =4.5 *10-9cm-1 Hz-1/2 at 2σ noise level near the peak of the absorption feature. This measurement is the first for acetic acid at this excitation level. Preliminary results for acetic acid show the peak occurs near 615nm. Procedures for separating the monomer and dimer contribution will be presented. We would like to acknowledge support from NSF award #0803016 and NOAA-EPP award #NA06OAR4810187.

  10. Characterization of acetic acid bacteria in "traditional balsamic vinegar".

    PubMed

    Gullo, Maria; Caggia, Cinzia; De Vero, Luciana; Giudici, Paolo

    2006-02-01

    This study evaluated the glucose tolerance of acetic acid bacteria strains isolated from Traditional Balsamic Vinegar. The results showed that the greatest hurdle to acetic acid bacteria growth is the high sugar concentration, since the majority of the isolated strains are inhibited by 25% of glucose. Sugar tolerance is an important technological trait because Traditional Balsamic Vinegar is made with concentrated cooked must. On the contrary, ethanol concentration of the cooked and fermented must is less significant for acetic acid bacteria growth. A tentative identification of the isolated strains was done by 16S-23S-5S rDNA PCR/RFLP technique and the isolated strains were clustered: 32 strains belong to Gluconacetobacter xylinus group, two strains to Acetobacter pasteurianus group and one to Acetobacter aceti. PMID:16214251

  11. Diastereoselective additions of titanium enolates from N-glycolyl thiazolidinethiones to acetals.

    PubMed

    Baiget, Jessica; Caba, Marta; Gálvez, Erik; Romea, Pedro; Urpí, Fèlix; Font-Bardia, Mercè

    2012-10-01

    The stereochemical outcome of the Lewis acid-mediated glycolate addition of the titanium enolates from protected N-hydroxyacetyl-4-isopropyl-1,3-thiazolidine-2-thiones to dimethyl and dibenzyl acetals depends on the hydroxyl protecting group. Particularly, the pivaloyl protected glycolate derivative provides the reluctant anti adducts in high yields and diastereomeric ratios, which can be isolated and further converted in enantiomerically pure form to β-methoxy or β-benzyloxy α-pivaloyloxy carbonyl fragments in a straightforward manner. PMID:22985246

  12. 21 CFR 862.1390 - 5-Hydroxyindole acetic acid/serotonin test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false 5-Hydroxyindole acetic acid/serotonin test system... Test Systems § 862.1390 5-Hydroxyindole acetic acid/serotonin test system. (a) Identification. A 5-hydroxyindole acetic acid/serotonin test system is a device intended to measure 5-hydroxyindole acetic...

  13. 21 CFR 862.1390 - 5-Hydroxyindole acetic acid/serotonin test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false 5-Hydroxyindole acetic acid/serotonin test system... Test Systems § 862.1390 5-Hydroxyindole acetic acid/serotonin test system. (a) Identification. A 5-hydroxyindole acetic acid/serotonin test system is a device intended to measure 5-hydroxyindole acetic...

  14. 21 CFR 862.1390 - 5-Hydroxyindole acetic acid/serotonin test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false 5-Hydroxyindole acetic acid/serotonin test system... Test Systems § 862.1390 5-Hydroxyindole acetic acid/serotonin test system. (a) Identification. A 5-hydroxyindole acetic acid/serotonin test system is a device intended to measure 5-hydroxyindole acetic...

  15. Adsorptive Membranes vs. Resins for Acetic Acid Removal from Biomass Hydrolysates

    SciTech Connect

    Han, B.; Carvalho, W.; Canilha, L.; da Silva, S. S.; e Silva, J. B. A.; McMillan, J. D.; Wickramasinghe, S. R.

    2006-01-01

    Acetic acid is a compound commonly found in hemicellulosic hydrolysates. This weak acid strongly influences the bioconversion of sugar containing hydrolysates. Previous investigators have used anion exchange resins for acetic acid removal from different hemicellulosic hydrolysates. In this study, the efficiency of an anion exchange membrane was compared to that of an anion exchange resin, for acetic acid removal from a DI water solution and an acidic hemicellulose hydrolysate pretreated using two different methods. Ion exchange membranes and resins have very different geometries. Here the performance of membranes and resins is compared using two dimensionless parameters, the relative mass throughput and chromatographic bed number. The relative mass throughput arises naturally from the Thomas solution for ion exchange. The results show that the membrane exhibit better performance in terms of capacity, and loss of the desired sugars. In addition acetic acid may be eluted at a higher concentration from the membrane thus leading to the possibility of recovery and re-use of the acetic acid.

  16. Lipidomic profiling of Saccharomyces cerevisiae and Zygosaccharomyces bailii reveals critical changes in lipid composition in response to acetic acid stress.

    PubMed

    Lindberg, Lina; Santos, Aline Xs; Riezman, Howard; Olsson, Lisbeth; Bettiga, Maurizio

    2013-01-01

    When using microorganisms as cell factories in the production of bio-based fuels or chemicals from lignocellulosic hydrolysate, inhibitory concentrations of acetic acid, released from the biomass, reduce the production rate. The undissociated form of acetic acid enters the cell by passive diffusion across the lipid bilayer, mediating toxic effects inside the cell. In order to elucidate a possible link between lipid composition and acetic acid stress, the present study presents detailed lipidomic profiling of the major lipid species found in the plasma membrane, including glycerophospholipids, sphingolipids and sterols, in Saccharomyces cerevisiae (CEN.PK 113_7D) and Zygosaccharomyces bailii (CBS7555) cultured with acetic acid. Detailed physiological characterization of the response of the two yeasts to acetic acid has also been performed in aerobic batch cultivations using bioreactors. Physiological characterization revealed, as expected, that Z. bailii is more tolerant to acetic acid than S. cerevisiae. Z. bailii grew at acetic acid concentrations above 24 g L(-1), while limited growth of S. cerevisiae was observed after 11 h when cultured with only 12 g L(-1) acetic acid. Detailed lipidomic profiling using electrospray ionization, multiple-reaction-monitoring mass spectrometry (ESI-MRM-MS) showed remarkable changes in the glycerophospholipid composition of Z. bailii, including an increase in saturated glycerophospholipids and considerable increases in complex sphingolipids in both S. cerevisiae (IPC 6.2×, MIPC 9.1×, M(IP)2C 2.2×) and Z. bailii (IPC 4.9×, MIPC 2.7×, M(IP)2C 2.7×), when cultured with acetic acid. In addition, the basal level of complex sphingolipids was significantly higher in Z. bailii than in S. cerevisiae, further emphasizing the proposed link between lipid saturation, high sphingolipid levels and acetic acid tolerance. The results also suggest that acetic acid tolerance is associated with the ability of a given strain to generate large

  17. Condensation of acetol and acetic acid vapor with sprayed liquid

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A cellulose-derived fraction of biomass pyrolysis vapor was simulated by evaporating acetol and acetic acid (AA) from flasks on a hot plate. The liquid in the flasks was infused with heated nitrogen. The vapor/nitrogen stream was superheated in a tube oven and condensed by contact with a cloud of ...

  18. Thermodynamic analysis of acetic acid steam reforming for hydrogen production

    NASA Astrophysics Data System (ADS)

    Goicoechea, Saioa; Ehrich, Heike; Arias, Pedro L.; Kockmann, Norbert

    2015-04-01

    A thermodynamic analysis of hydrogen generation by acetic acid steam reforming has been carried out with respect to applications in solid oxide fuel cells. The effect of operating parameters on equilibrium composition has been examined focusing especially on hydrogen and carbon monoxide production, which are the fuels in this type of fuel cell. The temperature, steam to acetic acid ratio, and to a lesser extent pressure affect significantly the equilibrium product distribution due to their influence on steam reforming, thermal decomposition and water-gas shift reaction. The study shows that steam reforming of acetic acid with a steam to acetic acid ratio of 2 to 1 is thermodynamically feasible with hydrogen, carbon monoxide and water as the main products at the equilibrium at temperatures higher than 700 °C, and achieving CO/CO2 ratios higher than 1. Thus, it can be concluded that within the operation temperature range of solid oxide fuel cells - between 700 °C and 1000 °C - the production of a gas rich in hydrogen and carbon monoxide is promoted.

  19. Occurrence and metabolism of 7-hydroxy-2-indolinone-3-acetic acid in Zea mays

    NASA Technical Reports Server (NTRS)

    Lewer, P.; Bandurski, R. S.

    1987-01-01

    7-Hydroxy-2-indolinone-3-acetic acid was identified as a catabolite of indole-3-acetic acid in germinating kernels of Zea mays and found to be present in amounts of ca 3.1 nmol/kernel. 7-Hydroxy-2-indolinone-3-acetic acid was shown to be a biosynthetic intermediate between 2-indolinone-3-acetic acid and 7-hydroxy-2-indolinone-3-acetic acid-7'-O-glucoside in both kernels and roots of Zea mays. Further metabolism of 7-hydroxy-2-[5-3H]-indolinone-3-acetic acid-7'-O-glucoside occurred to yield tritiated water plus, as yet, uncharacterized products.

  20. Effects of acetic acid on light scattering from cells

    PubMed Central

    Marina, Oana C.; Sanders, Claire K.

    2012-01-01

    Abstract. Acetic acid has been used for decades as an aid for the detection of precancerous cervical lesions, and the use of acetic acid is being investigated in several other tissues. Nonetheless, the mechanism of acetowhitening is unclear. This work tests some of the hypotheses in the literature and measures changes in light scattering specific to the nucleus and the cytoplasm. Wide angle side scattering from both the nucleus and the cytoplasm increases with acetic application to tumorigenic cells, with the increase in nuclear scattering being greater. In one cell line, the changes in nuclear scattering are likely due to an increase in number or scattering efficiency of scattering centers smaller than the wavelength of excitation light. There are likely several cellular changes that cause acetowhitening and the cellular changes may differ with cell type. These results should lead to a better understanding of acetowhitening and potentially the development of adjunct techniques to improve the utility of acetic acid application. For the well-studied case of cervical tissue, acetowhitening has been shown to be sensitive, but not specific for oncogenic changes needing treatment. PMID:23224185

  1. The Fate of Acetic Acid during Glucose Co-Metabolism by the Spoilage Yeast Zygosaccharomyces bailii

    PubMed Central

    Rodrigues, Fernando; Sousa, Maria João; Ludovico, Paula; Santos, Helena; Côrte-Real, Manuela; Leão, Cecília

    2012-01-01

    Zygosaccharomyces bailii is one of the most widely represented spoilage yeast species, being able to metabolise acetic acid in the presence of glucose. To clarify whether simultaneous utilisation of the two substrates affects growth efficiency, we examined growth in single- and mixed-substrate cultures with glucose and acetic acid. Our findings indicate that the biomass yield in the first phase of growth is the result of the weighted sum of the respective biomass yields on single-substrate medium, supporting the conclusion that biomass yield on each substrate is not affected by the presence of the other at pH 3.0 and 5.0, at least for the substrate concentrations examined. In vivo 13C-NMR spectroscopy studies showed that the gluconeogenic pathway is not operational and that [2−13C]acetate is metabolised via the Krebs cycle leading to the production of glutamate labelled on C2, C3 and C4. The incorporation of [U-14C]acetate in the cellular constituents resulted mainly in the labelling of the protein and lipid pools 51.5% and 31.5%, respectively. Overall, our data establish that glucose is metabolised primarily through the glycolytic pathway, and acetic acid is used as an additional source of acetyl-CoA both for lipid synthesis and the Krebs cycle. This study provides useful clues for the design of new strategies aimed at overcoming yeast spoilage in acidic, sugar-containing food environments. Moreover, the elucidation of the molecular basis underlying the resistance phenotype of Z. bailii to acetic acid will have a potential impact on the improvement of the performance of S. cerevisiae industrial strains often exposed to acetic acid stress conditions, such as in wine and bioethanol production. PMID:23285028

  2. [Conversion of acetic acid to methane by thermophiles

    SciTech Connect

    Zinder, S.H.

    1993-01-01

    The primary goal of this project is to obtain a better understanding of thermophilic microorganisms which convert acetic acid to CH[sub 4]. The previous funding period represents a departure from earlier research in this laboratory, which was more physiological and ecological. The present work is centered on the biochemistry of the thermophile Methanothrix sp. strain CALS-1. this organism presents a unique opportunity, with its purity and relatively rapid growth, to do comparative biochemical studies with the other major acetotrophic genus Methanosarcina. We previously found that Methanothrix is capable of using acetate at concentrations 100 fold lower than Methanosarcina. This finding suggests that there are significant differences in the pathways of methanogenesis from acetate in the two genera.

  3. [Conversion of acetic acid to methane by thermophiles: Progress report

    SciTech Connect

    Zinder, S.

    1991-12-31

    The objective of this project is to provide an understanding of thermophilic anaerobic microorganisms capable of breaking down acetic acid, the precursor of two-thirds of the methane produced by anaerobic bioreactors. Recent results include: (1) the isolation of Methanothrix strain CALLS-1, which grows much more rapidly than mesophilic strains; (2) the demonstration that thermophilic cultures of Methanosarcina and Methanothrix show minimum thresholds for acetate utilization of 1--2.5 mM and 10--20{mu}m respectively, in agreement with ecological data indicating that Methanothrix is favored by low acetate concentration; (3) the demonstration of high levels of thermostable acetyl-coA synthetase and carbon monoxide dehydrogenase in cell-free extracts of Methanothrix strains CALS-1; (4) the demonstration of methanogenesis from acetate and ATP in cell free extracts of strain CALS-1. (5) the demonstration that methanogenesis from acetate required 2 ATP/methane, and, in contrast to Methanosarcina, was independent of hydrogen and other electron donors; (6) the finding that entropy effects must be considered when predicting the level of hydrogen in thermophilic syntrophic cultures. (7) the isolation and characterization of the Desulfotomaculum thermoacetoxidans. Current research is centered on factors which allow thermophilic Methanothrix to compete with Methanosarcina.

  4. (Conversion of acetic acid to methane by thermophiles: Progress report)

    SciTech Connect

    Zinder, S.

    1991-01-01

    The objective of this project is to provide an understanding of thermophilic anaerobic microorganisms capable of breaking down acetic acid, the precursor of two-thirds of the methane produced by anaerobic bioreactors. Recent results include: (1) the isolation of Methanothrix strain CALLS-1, which grows much more rapidly than mesophilic strains; (2) the demonstration that thermophilic cultures of Methanosarcina and Methanothrix show minimum thresholds for acetate utilization of 1--2.5 mM and 10--20{mu}m respectively, in agreement with ecological data indicating that Methanothrix is favored by low acetate concentration; (3) the demonstration of high levels of thermostable acetyl-coA synthetase and carbon monoxide dehydrogenase in cell-free extracts of Methanothrix strains CALS-1; (4) the demonstration of methanogenesis from acetate and ATP in cell free extracts of strain CALS-1. (5) the demonstration that methanogenesis from acetate required 2 ATP/methane, and, in contrast to Methanosarcina, was independent of hydrogen and other electron donors; (6) the finding that entropy effects must be considered when predicting the level of hydrogen in thermophilic syntrophic cultures. (7) the isolation and characterization of the Desulfotomaculum thermoacetoxidans. Current research is centered on factors which allow thermophilic Methanothrix to compete with Methanosarcina.

  5. 21 CFR 175.350 - Vinyl acetate/crotonic acid copolymer.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Vinyl acetate/crotonic acid copolymer. 175.350 Section 175.350 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) INDIRECT FOOD ADDITIVES: ADHESIVES AND COMPONENTS OF COATINGS Substances for Use as Components...

  6. Interaction of acetic acid and phenylacetaldehyde as attractants for trapping pest species of moths (Lepidoptera: Noctuidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phenylacetaldehyde is a flower volatile and attractant for many nectar-seeking moths. Acetic acid is a microbial fermentation product that is present in insect sweet baits. It is weakly attractive to some moths and other insects, but can be additive or synergistic with other compounds to make more p...

  7. 21 CFR 175.350 - Vinyl acetate/crotonic acid copolymer.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Vinyl acetate/crotonic acid copolymer. 175.350 Section 175.350 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) INDIRECT FOOD ADDITIVES: ADHESIVES AND COMPONENTS...

  8. Crystal structure of febuxostat-acetic acid (1/1).

    PubMed

    Wu, Min; Hu, Xiu-Rong; Gu, Jian-Ming; Tang, Gu-Ping

    2015-05-01

    The asymmetric unit of the title compound [systematic name: 2-(3-cyano-4-iso-butyl-oxyphen-yl)-4-methyl-thia-zole-5-carb-oxy-lic acid-acetic acid (1/1)], C16H16N2O3S·CH3COOH, contains a febuxostat mol-ecule and an acetic acid mol-ecule. In the febuxostat mol-ecule, the thia-zole ring is nearly coplanar with the benzene ring [dihedral angle = 3.24 (2)°]. In the crystal, the febuxostat and acetic acid mol-ecules are linked by O-H⋯O, O-H⋯N hydrogen bonds and weak C-H⋯O hydrogen bonds, forming supra-molecular chains propagating along the b-axis direction. π-π stacking is observed between nearly parallel thia-zole and benzene rings of adjacent mol-ecules; the centroid-to-centroid distances are 3.8064 (17) and 3.9296 (17) Å. PMID:25995912

  9. Acetic acid bacteria spoilage of bottled red wine -- a review.

    PubMed

    Bartowsky, Eveline J; Henschke, Paul A

    2008-06-30

    Acetic acid bacteria (AAB) are ubiquitous organisms that are well adapted to sugar and ethanol rich environments. This family of Gram-positive bacteria are well known for their ability to produce acetic acid, the main constituent in vinegar. The oxidation of ethanol through acetaldehyde to acetic acid is well understood and characterised. AAB form part of the complex natural microbial flora of grapes and wine, however their presence is less desirable than the lactic acid bacteria and yeast. Even though AAB were described by Pasteur in the 1850s, wine associated AAB are still difficult to cultivate on artificial laboratory media and until more recently, their taxonomy has not been well characterised. Wine is at most risk of spoilage during production and the presence of these strictly aerobic bacteria in grape must and during wine maturation can be controlled by eliminating, or at least limiting oxygen, an essential growth factor. However, a new risk, spoilage of wine by AAB after packaging, has only recently been reported. As wine is not always sterile filtered prior to bottling, especially red wine, it often has a small resident bacterial population (<10(3) cfu/mL), which under conducive conditions might proliferate. Bottled red wines, sealed with natural cork closures, and stored in a vertical upright position may develop spoilage by acetic acid bacteria. This spoilage is evident as a distinct deposit of bacterial biofilm in the neck of the bottle at the interface of the wine and the headspace of air, and is accompanied with vinegar, sherry, bruised apple, nutty, and solvent like off-aromas, depending on the degree of spoilage. This review focuses on the wine associated AAB species, the aroma and flavour changes in wine due to AAB metabolism, discusses the importance of oxygen ingress into the bottle and presents a hypothesis for the mechanism of spoilage of bottled red wine. PMID:18237809

  10. Theophylline-7-acetic acid: lack of absorption and therapeutic effectiveness.

    PubMed Central

    Fleetham, J A; Owen, J A; May, B; Munt, P W; Nakatsu, K

    1979-01-01

    A double-blind cross-over trial was conducted to evaluate the effectiveness of oral theophylline-7-acetic acid (T7AA) in 13 asthmatic patients. Pulmonary function tests showed no difference between T7AA and placebo. No T7AA or theophylline was found in the sera of these patients or of healthy volunteers who took T7AA tablets or syrup. PMID:388714

  11. 21 CFR 175.350 - Vinyl acetate/crotonic acid copolymer.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... COATINGS Substances for Use as Components of Coatings § 175.350 Vinyl acetate/crotonic acid copolymer. A copolymer of vinyl acetate and crotonic acid may be safely used as a coating or as a component of a coating... of vinyl acetate and crotonic acid used as a coating or as a component of a coating conforming...

  12. 40 CFR 180.1258 - Acetic acid; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Acetic acid; exemption from the... Exemptions From Tolerances § 180.1258 Acetic acid; exemption from the requirement of a tolerance. (a) An... acetic acid when used as a preservative on post-harvest agricultural commodities intended for animal...

  13. Survival mechanism of Escherichia coli O157:H7 against combined treatment with acetic acid and sodium chloride.

    PubMed

    Lee, Sun-Young; Kang, Dong-Hyun

    2016-05-01

    The combination of salt and acid is commonly used in the production of many foods, including pickles and fermented foods. However, in our previous studies, the addition of salt significantly reduced the inhibitory effect of acetic acid on Escherichia coli O157:H7 in laboratory media and pickled cucumbers. Therefore, this study was conducted to determine the mechanism by which salt confers resistance against acetic acid in E. coli O157:H7. The addition of high concentrations (up to 9% or 15% [w/v]) of salt increased the resistance of E. coli O157:H7 to acetic acid treatment. Combined treatment with acetic acid and salt showed varying results among different bacterial strains (an antagonistic effect for E. coli O157:H7 and Shigella and a synergistic effect for Listeria monocytogenes and Staphylococcus aureus). The addition of salt increased the cytoplasmic pH of E. coli O157:H7, but decreased the cytoplasmic pH of L. monocytogenes and S. aureus on treatment with acetic acid. Therefore, the addition of salt increases the acid resistance of E. coli O157:H7 possibly by increasing its acid resistance response and consequently preventing the acidification of its cytoplasm by organic acids. PMID:26742620

  14. Change in the plasmid copy number in acetic acid bacteria in response to growth phase and acetic acid concentration.

    PubMed

    Akasaka, Naoki; Astuti, Wiwik; Ishii, Yuri; Hidese, Ryota; Sakoda, Hisao; Fujiwara, Shinsuke

    2015-06-01

    Plasmids pGE1 (2.5 kb), pGE2 (7.2 kb), and pGE3 (5.5 kb) were isolated from Gluconacetobacter europaeus KGMA0119, and sequence analyses revealed they harbored 3, 8, and 4 genes, respectively. Plasmid copy numbers (PCNs) were determined by real-time quantitative PCR at different stages of bacterial growth. When KGMA0119 was cultured in medium containing 0.4% ethanol and 0.5% acetic acid, PCN of pGE1 increased from 7 copies/genome in the logarithmic phase to a maximum of 12 copies/genome at the beginning of the stationary phase, before decreasing to 4 copies/genome in the late stationary phase. PCNs for pGE2 and pGE3 were maintained at 1-3 copies/genome during all phases of growth. Under a higher concentration of ethanol (3.2%) the PCN for pGE1 was slightly lower in all the growth stages, and those of pGE2 and pGE3 were unchanged. In the presence of 1.0% acetic acid, PCNs were higher for pGE1 (10 copies/genome) and pGE3 (6 copies/genome) during the logarithmic phase. Numbers for pGE2 did not change, indicating that pGE1 and pGE3 increase their PCNs in response to acetic acid. Plasmids pBE2 and pBE3 were constructed by ligating linearized pGE2 and pGE3 into pBR322. Both plasmids were replicable in Escherichia coli, Acetobacter pasteurianus and G. europaeus, highlighting their suitability as vectors for acetic acid bacteria. PMID:25575969

  15. Distinct Effects of Sorbic Acid and Acetic Acid on the Electrophysiology and Metabolism of Bacillus subtilis

    PubMed Central

    van Beilen, J. W. A.; Teixeira de Mattos, M. J.; Hellingwerf, K. J.

    2014-01-01

    Sorbic acid and acetic acid are among the weak organic acid preservatives most commonly used to improve the microbiological stability of foods. They have similar pKa values, but sorbic acid is a far more potent preservative. Weak organic acids are most effective at low pH. Under these circumstances, they are assumed to diffuse across the membrane as neutral undissociated acids. We show here that the level of initial intracellular acidification depends on the concentration of undissociated acid and less on the nature of the acid. Recovery of the internal pH depends on the presence of an energy source, but acidification of the cytosol causes a decrease in glucose flux. Furthermore, sorbic acid is a more potent uncoupler of the membrane potential than acetic acid. Together these effects may also slow the rate of ATP synthesis significantly and may thus (partially) explain sorbic acid's effectiveness. PMID:25038097

  16. Gas-Phase Structures of Ketene and Acetic Acid from Acetic Anhydride Using Very-High-Temperature Gas Electron Diffraction.

    PubMed

    Atkinson, Sandra J; Noble-Eddy, Robert; Masters, Sarah L

    2016-03-31

    The gas-phase molecular structure of ketene has been determined using samples generated by the pyrolysis of acetic anhydride (giving acetic acid and ketene), using one permutation of the very-high-temperature (VHT) inlet nozzle system designed and constructed for the gas electron diffraction (GED) apparatus based at the University of Canterbury. The gas-phase structures of acetic anhydride, acetic acid, and ketene are presented and compared to previous electron diffraction and microwave spectroscopy data to show improvements in data extraction and manipulation with current methods. Acetic anhydride was modeled with two conformers, rather than a complex dynamic model as in the previous study, to allow for inclusion of multiple pyrolysis products. The redetermined gas-phase structure of acetic anhydride (obtained using the structure analysis restrained by ab initio calculations for electron diffraction method) was compared to that from the original study, providing an improvement on the description of the low vibrational torsions compared to the dynamic model. Parameters for ketene and acetic acid (both generated by the pyrolysis of acetic anhydride) were also refined with higher accuracy than previously reported in GED studies, with structural parameter comparisons being made to prior experimental and theoretical studies. PMID:26916368

  17. The effect of oral sodium acetate administration on plasma acetate concentration and acid-base state in horses

    PubMed Central

    Waller, Amanda; Lindinger, Michael I

    2007-01-01

    Aim Sodium acetate (NaAcetate) has received some attention as an alkalinizing agent and possible alternative energy source for the horse, however the effects of oral administration remain largely unknown. The present study used the physicochemical approach to characterize the changes in acid-base status occurring after oral NaAcetate/acetic acid (NAA) administration in horses. Methods Jugular venous blood was sampled from 9 exercise-conditioned horses on 2 separate occasions, at rest and for 24 h following a competition exercise test (CET) designed to simulate the speed and endurance test of 3-day event. Immediately after the CETs horses were allowed water ad libitum and either: 1) 8 L of a hypertonic NaAcetate/acetic acid solution via nasogastric tube followed by a typical hay/grain meal (NAA trial); or 2) a hay/grain meal alone (Control trial). Results Oral NAA resulted in a profound plasma alkalosis marked by decreased plasma [H+] and increased plasma [TCO2] and [HCO3-] compared to Control. The primary contributor to the plasma alkalosis was an increased [SID], as a result of increased plasma [Na+] and decreased plasma [Cl-]. An increased [Atot], due to increased [PP] and a sustained increase in plasma [acetate], contributed a minor acidifying effect. Conclusion It is concluded that oral NaAcetate could be used as both an alkalinizing agent and an alternative energy source in the horse. PMID:18096070

  18. Overexpression of acetyl-CoA synthetase in Saccharomyces cerevisiae increases acetic acid tolerance

    PubMed Central

    Ding, Jun; Holzwarth, Garrett; Penner, Michael H.; Patton-Vogt, Jana; Bakalinsky, Alan T.

    2015-01-01

    Acetic acid-mediated inhibition of the fermentation of lignocellulose-derived sugars impedes development of plant biomass as a source of renewable ethanol. In order to overcome this inhibition, the capacity of Saccharomyces cerevisiae to synthesize acetyl-CoA from acetic acid was increased by overexpressing ACS2 encoding acetyl-coenzyme A synthetase. Overexpression of ACS2 resulted in higher resistance to acetic acid as measured by an increased growth rate and shorter lag phase relative to a wild-type control strain, suggesting that Acs2-mediated consumption of acetic acid during fermentation contributes to acetic acid detoxification. PMID:25673654

  19. Formation of biologically relevant carboxylic acids during the gamma irradiation of acetic acid

    NASA Technical Reports Server (NTRS)

    Negron-Mendoza, A.; Ponnamperuma, C.

    1976-01-01

    Irradiation of aqueous solutions of acetic acid with gamma rays produced several carboxylic acids in small yield. Their identification was based on the technique of gas chromatography combined with mass spectrometry. Some of these acids are Krebs Cycle intermediates. Their simultaneous formation in experiments simulating the primitive conditions on the earth suggests that metabolic pathways may have had their origin in prebiotic chemical processes.

  20. Gas Cluster Ion Beam Etching under Acetic Acid Vapor for Etch-Resistant Material

    NASA Astrophysics Data System (ADS)

    Yamaguchi, Akira; Hinoura, Ryo; Toyoda, Noriaki; Hara, Ken-ichi; Yamada, Isao

    2013-05-01

    Gas cluster ion beam (GCIB) etching of etch-resistant materials under acetic acid vapor was studied for development of new manufacturing process of future nonvolatile memory. Etching depths of various etch-resistant materials (Pt, Ru, Ta, CoFe) with acetic acid vapor during O2-GCIB irradiations were 1.8-10.7 times higher than those without acetic acid. Also, etching depths of Ru, Ta, CoFe by Ar-GCIB with acetic acid vapor were 2.2-16.1 times higher than those without acetic acid. Even after etching of Pt, smoothing of Pt was realized using O2-GCIB under acetic acid. From XPS and angular distribution of sputtered Pt, it was shown that PtOx layer was formed on Pt after O2-GCIB irradiation. PtOx reacted with acetic acid by GCIB bombardments; as a result, increase of etching depth was observed.

  1. Temperature dependence of hydrogen-bond dynamics in acetic acid-water solutions.

    PubMed

    D'Amico, Francesco; Bencivenga, Filippo; Gessini, Alessandro; Masciovecchio, Claudio

    2010-08-19

    An inelastic UV scattering experiment has been carried out on acetic acid-water solutions as a function of temperature and concentration. The analysis of experimental data indicates the presence of a crossover temperature (T(c) approximately 325 +/- 10 K). Above T(c), the energy of hydrogen bonds responsible for water-acetic acid and acetic acid-acetic acid interactions is strongly reduced. This leads to a reduction in the average number of water molecule interacting with acetic acid, as well as to a lower number of acetic acid clusters. The latter behavior can be mainly ascribed to a temperature change in the activation energy of carboxylic groups of acetic acid. These results may be also relevant to better understand the folding mechanism in protein-water solutions. PMID:20701390

  2. Forming microbial anodes with acetate addition decreases their capability to treat raw paper mill effluent.

    PubMed

    Ketep, Stéphanie F; Bergel, Alain; Bertrand, Marie; Barakat, Mohamed; Achouak, Wafa; Fourest, Eric

    2014-07-01

    Microbial anodes were formed under polarization at -0.3 V/SCE on graphite plates in effluents from a pulp and paper mill. The bioanodes formed with the addition of acetate led to the highest current densities (up to 6A/m(2)) but were then unable to oxidize the raw effluent efficiently (0.5A/m(2)). In contrast, the bioanodes formed without acetate addition were fully able to oxidize the organic matter contained in the effluent, giving up to 4.5A/m(2) in continuous mode. Bacterial communities showed less bacterial diversity for the acetate-fed bioanodes compared to those formed in raw effluents. Deltaproteobacteria were the most abundant taxonomic group, with a high diversity for bioanodes formed without acetate addition but with almost 100% Desulfuromonas for the acetate-fed bioanodes. The addition of acetate to form the microbial anodes induced microbial selection, which was detrimental to the treatment of the raw effluent. PMID:24862005

  3. Kinetic Modeling of Esterification of Ethylene Glycol with Acetic Acid

    NASA Astrophysics Data System (ADS)

    Yadav, Vishnu P.; Mukherjee, Rudra Palash; Bantraj, Kandi; Maity, Sunil K.

    2010-10-01

    The reaction kinetics of the esterification of ethylene glycol with acetic acid in the presence of cation exchange resin has been studied and kinetic models based on empirical and Langmuir approach has been developed. The Langmuir based model involving eight kinetic parameters fits experimental data much better compared to empirical model involving four kinetic parameters. The effect of temperature and catalyst loading on the reaction system has been analyzed. Further, the activation energy and frequency factor of the rate constants for Langmuir based model has been estimated.

  4. Kinetic Modeling of Esterification of Ethylene Glycol with Acetic Acid

    SciTech Connect

    Yadav, Vishnu P.; Maity, Sunil K.; Mukherjee, Rudra Palash; Bantraj, Kandi

    2010-10-26

    The reaction kinetics of the esterification of ethylene glycol with acetic acid in the presence of cation exchange resin has been studied and kinetic models based on empirical and Langmuir approach has been developed. The Langmuir based model involving eight kinetic parameters fits experimental data much better compared to empirical model involving four kinetic parameters. The effect of temperature and catalyst loading on the reaction system has been analyzed. Further, the activation energy and frequency factor of the rate constants for Langmuir based model has been estimated.

  5. Radioiron utilization and gossypol acetic acid in male rats

    SciTech Connect

    Tone, J.N.; Jensen, D.R.

    1985-01-01

    The 24-h incorporation of VZFe into circulating red blood cells, bone marrow, urine, liver, spleen, and skeletal muscle was measured in splenectomized and sham-splenectomized rats which had received a daily, oral dose of gossypol acetic acid (20 mg GAA/kg body wt) for 91 days. A significant decrease in total body weight gain was observed in all GAA treated animals. Splenectomized rats dosed with GAA exhibited a significant decrease in hemoglobin concentration, hematocrit and erythrocyte count. A significant increase in VZFe incorporation by red blood cells and a decrease in hepatic incorporation of VZFe indicate a preferential utilization of iron in erythropoiesis among GAA treated animals.

  6. Quantitative Structure of an Acetate Dye Molecule Analogue at the TiO2–Acetic Acid Interface

    PubMed Central

    2016-01-01

    The positions of atoms in and around acetate molecules at the rutile TiO2(110) interface with 0.1 M acetic acid have been determined with a precision of ±0.05 Å. Acetate is used as a surrogate for the carboxylate groups typically employed to anchor monocarboxylate dye molecules to TiO2 in dye-sensitized solar cells (DSSC). Structural analysis reveals small domains of ordered (2 × 1) acetate molecules, with substrate atoms closer to their bulk terminated positions compared to the clean UHV surface. Acetate is found in a bidentate bridge position, binding through both oxygen atoms to two 5-fold titanium atoms such that the molecular plane is along the [001] azimuth. Density functional theory calculations provide adsorption geometries in excellent agreement with experiment. The availability of these structural data will improve the accuracy of charge transport models for DSSC. PMID:27110318

  7. Improvement of acetic acid tolerance of Saccharomyces cerevisiae using a zinc-finger-based artificial transcription factor and identification of novel genes involved in acetic acid tolerance.

    PubMed

    Ma, Cui; Wei, Xiaowen; Sun, Cuihuan; Zhang, Fei; Xu, Jianren; Zhao, Xinqing; Bai, Fengwu

    2015-03-01

    Acetic acid is present in cellulosic hydrolysate as a potent inhibitor, and the superior acetic acid tolerance of Saccharomyces cerevisiae ensures good cell viability and efficient ethanol production when cellulosic raw materials are used as substrates. In this study, a mutant strain of S. cerevisiae ATCC4126 (Sc4126-M01) with improved acetic acid tolerance was obtained through screening strains transformed with an artificial zinc finger protein transcription factor (ZFP-TF) library. Further analysis indicated that improved acetic acid tolerance was associated with improved catalase (CAT) activity. The ZFP coding sequence associated with the improved phenotype was identified, and real-time RT-PCR analysis revealed that three of the possible genes involved in the enhanced acetic acid tolerance regulated by this ZFP-TF, namely YFL040W, QDR3, and IKS1, showed decreased transcription levels in Sc4126-M01 in the presence of acetic acid, compared to those in the control strain. Sc4126-M01 mutants having QDR3 and IKS1 deletion (ΔQDR3 and ΔIKS1) exhibited higher acetic acid tolerance than the wild-type strain under acetic acid treatment. Glucose consumption rate and ethanol productivity in the presence of 5 g/L acetic acid were improved in the ΔQDR3 mutant compared to the wild-type strain. Our studies demonstrated that the synthetic ZFP-TF library can be used to improve acetic acid tolerance of S. cerevisiae and that the employment of an artificial transcription factor can facilitate the exploration of novel functional genes involved in stress tolerance of S. cerevisiae. PMID:25698512

  8. Oxidation of indole-3-acetic acid to oxindole-3-acetic acid by etiolated and green corn tissues

    SciTech Connect

    Reinecke, D. )

    1989-04-01

    Etiolated corn tissues oxidase indole-3-acetic acid (IAA) to oxindole-3-acetic acid (OxIAA). This oxidation results in loss of auxin activity and may plant a role in regulating IAA-stimulated growth. The enzyme has been partially purified and characterized and shown to require O{sub 2}, and a heat-stable lipid-soluble corn factor which can be replaced by linolenic or linoleic acids in the oxidation of IAA. Corn oil was tested as a cofactor in the IAA oxidation reaction. Corn oil stimulated enzyme activity by 30% while trilinolein was inactive. The capacity of green tissue to oxidize IAA was examined by incubating leaf sections from 2 week old light-grown corn seedlings with {sup 14}C-IAA. OxIAA and IAA were separated from other IAA metabolites on a 3 ml anion exchange column. Of the IAA taken up by the sections, 13% was oxidized to OxIAA. This is the first evidence that green tissue of corn may also regulate IAA levels by oxidizing IAA to OxIAA.

  9. Unusal pattern of product inhibition: batch acetic acid fermentation

    SciTech Connect

    Bar, R.; Gainer, J.L.; Kirwan, D.J.

    1987-04-20

    The limited tolerance of microorganisms to their metabolic products results in inhibited growth and product formation. The relationship between the specific growth rate, micro, and the concentration of an inhibitory product has been described by a number of mathematical models. In most cases, micro was found to be inversely proportional to the product concentration and invariably the rate of substrate utilization followed the same pattern. In this communication, the authors report a rather unusual case in which the formation rate of a product, acetic acid, increased with a decreasing growth rate of the microorganism, Acetobacter aceti. Apparently, a similar behavior was mentioned in a review report with respect to Clostridium thermocellum in a batch culture but was not published in the freely circulating literature. The fermentation of ethanol to acetic acid, C/sub 2/H/sub 5/OH + O/sub 2/ = CH/sub 3/COOH + H/sub 2/O is clearly one of the oldest known fermentations. Because of its association with the commercial production of vinegar it has been a subject of extensive but rather technically oriented studies. Suprisingly, the uncommon uncoupling between the inhibited microbial growth and the product formation appears to have been unnoticed. 13 references.

  10. Determination of Endogenous Indole-3-Acetic Acid in Plagiochila arctica (Hepaticae) 1

    PubMed Central

    Law, David M.; Basile, Dominick V.; Basile, Margaret R.

    1985-01-01

    Endogenous indole-3-acetic acid (IAA) was found in axenically cultured gametophytes of the leafy liverwort, Plagiochila arctica Bryhn and Kaal., by high-performance liquid chromatography with electrochemical detection. Identification of the methylated auxin was confirmed by gas chromatography-mass spectrometry. Addition of 57 micromolar IAA to cultures increased relative production of ethylene. This is the first definitive (gas chromatography-mass spectrometry) demonstration of the natural occurrence of IAA in a bryophyte. PMID:16664164

  11. Lactobionic and cellobionic acid production profiles of the resting cells of acetic acid bacteria.

    PubMed

    Kiryu, Takaaki; Kiso, Taro; Nakano, Hirofumi; Murakami, Hiromi

    2015-01-01

    Lactobionic acid was produced by acetic acid bacteria to oxidize lactose. Gluconobacter spp. and Gluconacetobacter spp. showed higher lactose-oxidizing activities than Acetobacter spp. Gluconobacter frateurii NBRC3285 produced the highest amount of lactobionic acid per cell, among the strains tested. This bacterium assimilated neither lactose nor lactobionic acid. At high lactose concentration (30%), resting cells of the bacterium showed sufficient oxidizing activity for efficient production of lactobionic acid. These properties may contribute to industrial production of lactobionic acid by the bacterium. The bacterium showed higher oxidizing activity on cellobiose than that on lactose and produced cellobionic acid. PMID:25965080

  12. Exogenous Ghrelin Accelerates the Healing of Acetic Acid-Induced Colitis in Rats.

    PubMed

    Matuszyk, Aleksandra; Ceranowicz, Piotr; Warzecha, Zygmunt; Cieszkowski, Jakub; Ceranowicz, Dagmara; Gałązka, Krystyna; Bonior, Joanna; Jaworek, Jolanta; Bartuś, Krzysztof; Gil, Krzysztof; Olszanecki, Rafał; Dembiński, Artur

    2016-01-01

    Previous studies have shown that ghrelin reduces colonic inflammation induced by trinitrobenzene sulfonic acid and dextran sodium sulfate. In the present study we determined the effect of treatment with ghrelin on the course of acetic acid-induced colitis in rats. Rectal administration of 3% acetic acid solution led to induction of colitis in all animals. Damage of the colonic wall was accompanied by an increase in mucosal concentration of pro-inflammatory interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α), as well mucosal activity of myeloperoxidase. Moreover, induction of colitis led to a reduction in colonic blood flow and DNA synthesis. Administration of ghrelin after induction of colitis led to faster regeneration of the colonic wall and reduction in colonic levels of IL-1β, TNF-α, and myeloperoxidase. In addition, treatment with ghrelin improved mucosal DNA synthesis and blood flow. Our study disclosed that ghrelin exhibits a strong anti-inflammatory and healing effect in acetic acid-induced colitis. Our current observation in association with previous findings that ghrelin exhibits curative effect in trinitrobenzene sulfonic acid- and dextran sodium sulfate-induced colitis suggest that therapeutic effect of ghrelin in the colon is universal and independent of the primary cause of colitis. PMID:27598133

  13. Heterogeneous Reactions of Acetic Acid with Oxide Surfaces: Effects of Mineralogy and Relative Humidity.

    PubMed

    Tang, Mingjin; Larish, Whitney A; Fang, Yuan; Gankanda, Aruni; Grassian, Vicki H

    2016-07-21

    We have investigated the heterogeneous uptake of gaseous acetic acid on different oxides including γ-Al2O3, SiO2, and CaO under a range of relative humidity conditions. Under dry conditions, the uptake of acetic acid leads to the formation of both acetate and molecularly adsorbed acetic acid on γ-Al2O3 and CaO and only molecularly adsorbed acetic acid on SiO2. More importantly, under the conditions of this study, dimers are the major form for molecularly adsorbed acetic acid on all three particle surfaces investigated, even at low acetic acid pressures under which monomers are the dominant species in the gas phase. We have also determined saturation surface coverages for acetic acid adsorption on these three oxides under dry conditions as well as Langmuir adsorption constants in some cases. Kinetic analysis shows that the reaction rate of acetic acid increases by a factor of 3-5 for γ-Al2O3 when relative humidity increases from 0% to 15%, whereas for SiO2 particles, acetic acid and water are found to compete for surface adsorption sites. PMID:27322707

  14. Acetic acid and lithium chloride effects on hydrothermal carbonization of lignocellulosic biomass.

    PubMed

    Lynam, Joan G; Coronella, Charles J; Yan, Wei; Reza, Mohammad T; Vasquez, Victor R

    2011-05-01

    As a renewable non-food resource, lignocellulosic biomass has great potential as an energy source or feedstock for further conversion. However, challenges exist with supply logistics of this geographically scattered and perishable resource. Hydrothermal carbonization treats any kind of biomass in 200 to 260°C compressed water under an inert atmosphere to produce a hydrophobic solid of reduced mass and increased fuel value. A maximum in higher heating value (HHV) was found when 0.4 g of acetic acid was added per g of biomass. If 1g of LiCl and 0.4 g of acetic acid were added per g of biomass to the initial reaction solution, a 30% increase in HHV was found compared to the pretreatment with no additives, along with greater mass reduction. LiCl addition also reduces reaction pressure. Addition of acetic acid and/or LiCl to hydrothermal carbonization each contribute to increased HHV and reduced mass yield of the solid product. PMID:21411315

  15. Benzylidene Acetal Protecting Group as Carboxylic Acid Surrogate: Synthesis of Functionalized Uronic Acids and Sugar Amino Acids.

    PubMed

    Banerjee, Amit; Senthilkumar, Soundararasu; Baskaran, Sundarababu

    2016-01-18

    Direct oxidation of the 4,6-O-benzylidene acetal protecting group to C-6 carboxylic acid has been developed that provides an easy access to a wide range of biologically important and synthetically challenging uronic acid and sugar amino acid derivatives in good yields. The RuCl3 -NaIO4 -mediated oxidative cleavage method eliminates protection and deprotection steps and the reaction takes place under mild conditions. The dual role of the benzylidene acetal, as a protecting group and source of carboxylic acid, was exploited in the efficient synthesis of six-carbon sialic acid analogues and disaccharides bearing uronic acids, including glycosaminoglycan analogues. PMID:26572799

  16. Recent advances in nitrogen-fixing acetic acid bacteria.

    PubMed

    Pedraza, Raúl O

    2008-06-30

    Nitrogen is an essential plant nutrient, widely applied as N-fertilizer to improve yield of agriculturally important crops. An interesting alternative to avoid or reduce the use of N-fertilizers could be the exploitation of plant growth-promoting bacteria (PGPB), capable of enhancing growth and yield of many plant species, several of agronomic and ecological significance. PGPB belong to diverse genera, including Azospirillum, Azotobacter, Herbaspirillum, Bacillus, Burkholderia, Pseudomonas, Rhizobium, and Gluconacetobacter, among others. They are capable of promoting plant growth through different mechanisms including (in some cases), the biological nitrogen fixation (BNF), the enzymatic reduction of the atmospheric dinitrogen (N(2)) to ammonia, catalyzed by nitrogenase. Aerobic bacteria able to oxidize ethanol to acetic acid in neutral or acid media are candidates of belonging to the family Acetobacteraceae. At present, this family has been divided into ten genera: Acetobacter, Gluconacetobacter, Gluconobacter, Acidomonas, Asaia, Kozakia, Saccharibacter, Swaminathania, Neoasaia, and Granulibacter. Among them, only three genera include N(2)-fixing species: Gluconacetobacter, Swaminathania and Acetobacter. The first N(2)-fixing acetic acid bacterium (AAB) was described in Brazil. It was found inside tissues of the sugarcane plant, and first named as Acetobacter diazotrophicus, but then renamed as Gluconacetobacter diazotrophicus. Later, two new species within the genus Gluconacetobacter, associated to coffee plants, were described in Mexico: G. johannae and G. azotocaptans. A salt-tolerant bacterium named Swaminathania salitolerans was found associated to wild rice plants. Recently, N(2)-fixing Acetobacter peroxydans and Acetobacter nitrogenifigens, associated with rice plants and Kombucha tea, respectively, were described in India. In this paper, recent advances involving nitrogen-fixing AAB are presented. Their natural habitats, physiological and genetic aspects

  17. Improvement in HPLC separation of acetic acid and levulinic acid in the profiling of biomass hydrolysate.

    PubMed

    Xie, Rui; Tu, Maobing; Wu, Yonnie; Adhikari, Sushil

    2011-04-01

    5-Hydroxymethylfurfural (HMF) and furfural could be separated by the Aminex HPX-87H column chromatography, however, the separation and quantification of acetic acid and levulinic acid in biomass hydrolysate have been difficult with this method. In present study, the HPLC separation of acetic acid and levulinic acid on Aminex HPX-87H column has been investigated by varying column temperature, flow rate, and sulfuric acid content in the mobile phase. The column temperature was found critical in resolving acetic acid and levulinic acid. The resolution for two acids increased dramatically from 0.42 to 1.86 when the column temperature was lowered from 60 to 30 °C. So did the capacity factors for levulinic acid that was increased from 1.20 to 1.44 as the column temperature dropped. The optimum column temperature for the separation was found at 45 °C. Variation in flow rate and sulfuric acid concentration improved not as much as the column temperature did. PMID:21316945

  18. Effect of acetic acid on lipid accumulation by glucose-fed activated sludge cultures

    SciTech Connect

    Mondala, Andro; Hernandez, Rafael; French, Todd; McFarland, Linda; Sparks, Darrell; Holmes, William; Haque, Monica

    2012-01-01

    The effect of acetic acid, a lignocellulose hydrolysis by-product, on lipid accumulation by activated sludge cultures grown on glucose was investigated. This was done to assess the possible application of lignocellulose as low-cost and renewable fermentation substrates for biofuel feedstock production. Results: Biomass yield was reduced by around 54% at a 2 g L -1 acetic acid dosage but was increased by around 18% at 10 g L -1 acetic acid dosage relative to the control run. The final gravimetric lipid contents at 2 and 10 g L -1 acetic acid levels were 12.5 + 0.7% and 8.8 + 3.2% w/w, respectively, which were lower than the control (17.8 + 2.8% w/w). However, biodiesel yields from activated sludge grown with acetic acid (5.6 + 0.6% w/w for 2 g L -1 acetic acid and 4.2 + 3.0% w/w for 10 g L -1 acetic acid) were higher than in raw activated sludge (1-2% w/w). The fatty acid profiles of the accumulated lipids were similar with conventional plant oil biodiesel feedstocks. Conclusions: Acetic acid enhanced biomass production by activated sludge at high levels but reduced lipid production. Further studies are needed to enhance acetic acid utilization by activated sludge microorganisms for lipid biosynthesis.

  19. Transcript and metabolite alterations increase ganoderic acid content in Ganoderma lucidum using acetic acid as an inducer.

    PubMed

    Ren, Ang; Li, Xiong-Biao; Miao, Zhi-Gang; Shi, Liang; Jaing, Ai-Liang; Zhao, Ming-Wen

    2014-12-01

    Acetic acid at 5-8 mM increased ganoderic acid (GA) accumulation in Ganoderma lucidum. After optimization by the response surface methodology, the GA content reached 5.5/100 mg dry weight, an increase of 105% compared with the control. The intermediate metabolites of GA biosynthesis, lanosterol and squalene also increased to 47 and 15.8 μg/g dry weight, respectively, in response to acetic acid. Acetic acid significantly induced transcription levels of sqs, lano, hmgs and cyp51 in the GA biosynthesis pathway. An acetic acid-unregulated acetyl coenzyme A synthase (acs) gene was selected from ten candidate homologous acs genes. The results indicate that acetic acid alters the expression of genes related to acetic acid assimilation and increases GA biosynthesis and the metabolic levels of lanosterol, squalene and GA-a, thereby resulting in GA accumulation. PMID:25216642

  20. Dynamics of three organic acids (malic, acetic and succinic acid) in sunflower exposed to cadmium and lead.

    PubMed

    Niu, Zhixin; Li, Xiaodong; Sun, Lina; Sun, Tieheng

    2013-01-01

    Sunflower (Helianthus annuus L.) has been considered as a good candidate for bioaccumulation of heavy metals. In the present study, sunflower was used to enrich the cadmium and lead in sand culture during 90 days. Biomass, Cd and Pb uptake, three organic acids and pH in cultures were investigated. Results showed that the existence of Cd and Pb showed different interactions on the organic acids exudation. In single Cd treatments, malic and acetic acids in Cd10 showed an incremental tendency with time. In the mixed treatments of Cd and Pb, malic acids increased when 10 and 40 mg x L(-1) Cd were added into Pb50, but acetic acids in Pb50 were inhibited by Cd addition. The Cd10 supplied in Pb10 stimulated the secretion of malic and succinic acids. Moreover, the Cd or Pb uptake in sunflower showed various correlations with pH and some organic acids, which might be due to the fact that the Cd and Pb interfere with the organic acids secretion in rhizosphere of sunflower, and the changes of organic acids altered the form and bioavailability of Cd and Pb in cultures conversely. PMID:23819268

  1. Lactobacillus acidophilus NCFM affects vitamin E acetate metabolism and intestinal bile acid signature in monocolonized mice

    PubMed Central

    Roager, Henrik M; Sulek, Karolina; Skov, Kasper; Frandsen, Henrik L; Smedsgaard, Jørn; Wilcks, Andrea; Skov, Thomas H; Villas-Boas, Silas G; Licht, Tine R

    2014-01-01

    Monocolonization of germ-free (GF) mice enables the study of specific bacterial species in vivo. Lactobacillus acidophilus NCFMTM (NCFM) is a probiotic strain; however, many of the mechanisms behind its health-promoting effect remain unknown. Here, we studied the effects of NCFM on the metabolome of jejunum, cecum, and colon of NCFM monocolonized (MC) and GF mice using liquid chromatography coupled to mass-spectrometry (LC-MS). The study adds to existing evidence that NCFM in vivo affects the bile acid signature of mice, in particular by deconjugation. Furthermore, we confirmed that carbohydrate metabolism is affected by NCFM in the mouse intestine as especially the digestion of oligosaccharides (penta- and tetrasaccharides) was increased in MC mice. Additionally, levels of α-tocopherol acetate (vitamin E acetate) were higher in the intestine of GF mice than in MC mice, suggesting that NCFM affects the vitamin E acetate metabolism. NCFM did not digest vitamin E acetate in vitro, suggesting that direct bacterial metabolism was not the cause of the altered metabolome in vivo. Taken together, our results suggest that NCFM affects intestinal carbohydrate metabolism, bile acid metabolism and vitamin E metabolism, although it remains to be investigated whether this effect is unique to NCFM. PMID:24717228

  2. Lactobacillus acidophilus NCFM affects vitamin E acetate metabolism and intestinal bile acid signature in monocolonized mice.

    PubMed

    Roager, Henrik M; Sulek, Karolina; Skov, Kasper; Frandsen, Henrik L; Smedsgaard, Jørn; Wilcks, Andrea; Skov, Thomas H; Villas-Boas, Silas G; Licht, Tine R

    2014-01-01

    Monocolonization of germ-free (GF) mice enables the study of specific bacterial species in vivo. Lactobacillus acidophilus NCFM(TM) (NCFM) is a probiotic strain; however, many of the mechanisms behind its health-promoting effect remain unknown. Here, we studied the effects of NCFM on the metabolome of jejunum, cecum, and colon of NCFM monocolonized (MC) and GF mice using liquid chromatography coupled to mass-spectrometry (LC-MS). The study adds to existing evidence that NCFM in vivo affects the bile acid signature of mice, in particular by deconjugation. Furthermore, we confirmed that carbohydrate metabolism is affected by NCFM in the mouse intestine as especially the digestion of oligosaccharides (penta- and tetrasaccharides) was increased in MC mice. Additionally, levels of α-tocopherol acetate (vitamin E acetate) were higher in the intestine of GF mice than in MC mice, suggesting that NCFM affects the vitamin E acetate metabolism. NCFM did not digest vitamin E acetate in vitro, suggesting that direct bacterial metabolism was not the cause of the altered metabolome in vivo. Taken together, our results suggest that NCFM affects intestinal carbohydrate metabolism, bile acid metabolism and vitamin E metabolism, although it remains to be investigated whether this effect is unique to NCFM. PMID:24717228

  3. Measurements of Acetic Acid and its Relationships with Trace Gases on Appledore Island, ME during the ICARTT Campaign

    NASA Astrophysics Data System (ADS)

    Haase, K. B.; Sive, B. C.; White, M. L.; Russo, R. S.; Ambrose, J. L.; Zhou, Y.; Talbot, R. W.

    2011-12-01

    Acetic acid is ubiquitously present in the ambient atmosphere. Acetic acid, along with formic acid, is the one of the most abundant gas phase organic acids with mixing ratios reaching into the tens of parts per billion by volume (ppbv) range, and can influence the pH of aerosols and precipitation. The magnitude of the sources and sinks of acetic acid in the environment is not well understood (~24 Tg/yr of missing emissions globally), as they are widely dispersed and measurements are relatively challenging to accomplish using established techniques. Here, the application of Proton Transfer Reaction Mass Spectrometry (PTR-MS) is explored as a technique for quantification of ambient acetic acid. Direct calibrations of PTR-MS instruments at low ppbv levels show good linearity and fast response, and during the ICARTT campaign, a PTR-MS measured acetic acid and a suite of other volatile organic compounds on Appledore Island, ME over a period of 6 weeks. During the campaign, the average mixing ratio of acetic acid on the island was 607.9 ± 341.8 (1σ) pptv with a median of 530 pptv. Mixing ratios of acetic acid observed on the island showed diurnal variations corresponding land breeze/sea breeze transport, similar to other pollutants including ozone and carbon monoxide, indicating that acetic acid was advected to the sample site, and not a product of local emissions. Additionally, no mixing ratio dependence on wind speed was found, indicating that at this location, loss due to dry deposition to the ocean during transport was minimal. Over the course of the campaign, acetic acid showed complex relationships with a range of other VOCs, indicating a diverse set of sources and further showing the utility of the PTR-MS technique for monitoring acetic acid. Mixing ratios of acetic acid showed correlations with different compounds at different times, indicating a complex source signature comprised of (1) anthropogenic emissions, (2) biomass burning, and (3) photochemical

  4. Leaching of spent lead acid battery paste components by sodium citrate and acetic acid.

    PubMed

    Zhu, Xinfeng; He, Xiong; Yang, Jiakuan; Gao, Linxia; Liu, Jianwen; Yang, Danni; Sun, Xiaojuan; Zhang, Wei; Wang, Qin; Kumar, R Vasant

    2013-04-15

    A sustainable method, with minimal pollution and low energy cost in comparison with the conventional smelting methods, is proposed for treating components of spent lead-acid battery pastes in aqueous organic acid(s). In this study, PbO, PbO2, and PbSO4, the three major components in a spent lead paste, were individually reacted with a mixture of aqueous sodium citrate and acetic acid solution. Pure lead citrate precursor of Pb3(C6H5O7)2 · 3H2O is the only product crystallized in each leaching experiment. Conditions were optimized for individual lead compounds which were then used as the basis for leaching real industrial spent paste. In this work, efficient leaching process is achieved and raw material cost is reduced by using aqueous sodium citrate and acetic acid, instead of aqueous sodium citrate and citric acid as reported in a pioneering hydrometallurgical method earlier. Acetic acid is not only cheaper than citric acid but is also more effective in aiding dissolution of the lead compounds thus speeding up the leaching process in comparison with citric acid. Lead citrate is readily crystallized from the aqueous solution due to its low solubility and can be combusted to directly produce leady oxide as a precursor for making new battery pastes. PMID:23500418

  5. Crystal structure of 7,8-benzocoumarin-4-acetic acid

    PubMed Central

    Swamy, R. Ranga; Gowda, Ramakrishna; Gowda, K. V. Arjuna; Basanagouda, Mahantesha

    2015-01-01

    The fused-ring system in the title compound [systematic name: 2-(2-oxo-2H-benzo[h]chromen-4-yl)acetic acid], C15H10O4, is almost planar (r.m.s. deviation = 0.031 Å) and the Car—C—C=O (ar = aromatic) torsion angle for the side chain is −134.4 (3)°. In the crystal, mol­ecules are linked by O—H⋯O hydrogen bonds, generating [100] C(8) chains, where the acceptor atom is the exocyclic O atom of the fused-ring system. The packing is consolidated by a very weak C—H⋯O hydrogen bond to the same acceptor atom. Together, these inter­actions lead to undulating (001) layers in the crystal. PMID:26396827

  6. [Removal of tattoos by CO2 laser and acetic acid].

    PubMed

    Di Quirico, R; Pallini, G; Di Domenicantonio, G; Astolfi, A; Bindi, F; Gianfelice, F

    1992-10-31

    The Authors pay attention to small tattoo removal by means of the utilization of the CO2 laser. Moreover, the Authors emphasize the drawback of double treatment which, usually, the patient suffers in tattoo removal by CO2 laser. Then, the pressure of the Authors is small sized tattoo removal in only one sitting achieving so an excellent esthetic result. Besides, the Authors, in this medical study, explains two methods for tattoo removal. In the study's results, the Authors describes the manner and the time of the two lesion recovery by the different manners of treatment. Finally, the Authors affirms the great consequence of the surgical CO2 laser, they don't fail, however, to affirm that the laser and acetic acid combination is an excellent procedure for small tattoo removal. PMID:1480288

  7. Inflammatory cells’ role in acetic acid-induced colitis

    PubMed Central

    Sanei, Mohammad H.; Hadizadeh, Fatemeh; Adibi, Peyman; Alavi, Sayyed Ali

    2014-01-01

    Background: Free radicals are the known mechanisms responsible for inducing colitis with two origins: Inflammatory cells and tissues. Only the inflammatory cells can be controlled by corticosteroids. Our aim was to assess the importance of neutrophils as one of the inflammatory cells in inducing colitis and to evaluate the efficacy of corticosteroids in the treatment of inflammatory bowel disease (IBD). Materials and Methods: Thirty-six mice were divided into six groups of six mice each. Colitis was induced in three groups by exposing them to acetic acid through enema (group 1), ex vivo (group 3), and enema after immune suppression (group 5). Each group had one control group that was exposed to water injection instead of acetic acid. Tissue samples were evaluated and compared based on macroscopic damages and biochemical and pathological results. Results: Considering neutrophilic infiltration, there were significant differences between groups 1, 3, 5, and the control of group 1. Groups 3, 5, and their controls, and group 1 and the control of group 3 had significant differences in terms of goblet depletion. Based on tissue originated H2O2, we found significant differences between group 1 and its control and group 3, and also between groups 5 and the control of group 3. All the three groups were significantly different from their controls based on Ferric Reducing Ability of Plasma (FRAP) and such differences were also seen between group 1 with two other groups. Conclusion: Neutrophils may not be the only cause of oxidation process in colitis, and also makes the effectiveness of corticosteroids in the treatment of this disease doubtful. PMID:25337523

  8. Acetic acid and aromatics units planned in China

    SciTech Connect

    Alperowicz, N.

    1993-01-27

    The Shanghai Wujing Chemical Complex (SWCC; Shanghai) is proceeding with construction of an acetic acid plant. The 100,000-m.t./year until will use BP Chemicals carbonylation technology, originally developed by Monsanto. John Brown has been selected by China National Technical Import Corp. (CNTIC) to supply the plant, Chinese sources say. The UK contractor, which competed against Mitsui Engineering Shipbuilding (Tokyo) and Lurgi (Frankfurt), has built a similar plant for BP in the UK, although using different technology. The new plant will require 54,000 m.t./year of methanol, which is available onsite. Carbon monoxide will be delivered from a new plant. The acetic acid unit will joint two other acetic plants in China supplied some time ago by Uhde (Dortmund). SWCC is due to be integrated with two adjacent complexes to form Shanghai Pacific Chemical. Meanwhile, four groups are competing to supply a UOP-process aromatics complex for Jilin Chemical Industrial Corp. They are Toyo Engineering, Lurgi, Lucky/Foster Wheeler, and Eurotechnica. The complex will include plants with annual capacities for 115,000 m.t. of benzene, 90,000 m.t. of ortho-xylene, 93,000 m.t. of mixed xylenes, and 20,000 m.t. of toluene. The plants will form part of a $2-billion petrochemical complex based on a 300,000-m.t./year ethylene plant awarded last year to a consortium of Samsung Engineering and Linde. Downstream plants will have annual capacities for 120,000 m.t. of linear low-density polyethylene, 80,000 m.t. of ethylene oxide, 100,000 m.t. of ethylene glycol, 80,000 m.t. of phenol, 100,000 m.t. of acrylonitrile, 20,000 m.t. of sodium cyanide, 40,000 m.t. of phthalic anhydride, 40,000 m.t. of ethylene propylene rubber, 20,000 m.t. of styrene butadiene styrene, and 30,000 m.t. of acrylic fiber.

  9. Comparative Genomics of Acetobacterpasteurianus Ab3, an Acetic Acid Producing Strain Isolated from Chinese Traditional Rice Vinegar Meiguichu.

    PubMed

    Xia, Kai; Li, Yudong; Sun, Jing; Liang, Xinle

    2016-01-01

    Acetobacter pasteurianus, an acetic acid resistant bacterium belonging to alpha-proteobacteria, has been widely used to produce vinegar in the food industry. To understand the mechanism of its high tolerance to acetic acid and robust ability of oxidizing ethanol to acetic acid (> 12%, w/v), we described the 3.1 Mb complete genome sequence (including 0.28 M plasmid sequence) with a G+C content of 52.4% of A. pasteurianus Ab3, which was isolated from the traditional Chinese rice vinegar (Meiguichu) fermentation process. Automatic annotation of the complete genome revealed 2,786 protein-coding genes and 73 RNA genes. The comparative genome analysis among A. pasteurianus strains revealed that A. pasteurianus Ab3 possesses many unique genes potentially involved in acetic acid resistance mechanisms. In particular, two-component systems or toxin-antitoxin systems may be the signal pathway and modulatory network in A. pasteurianus to cope with acid stress. In addition, the large numbers of unique transport systems may also be related to its acid resistance capacity and cell fitness. Our results provide new clues to understanding the underlying mechanisms of acetic acid resistance in Acetobacter species and guiding industrial strain breeding for vinegar fermentation processes. PMID:27611790

  10. Preparation and characterization of physicochemical properties of glacial acetic acid modified Gadung (Diocorea hispida Dennst) flours.

    PubMed

    Kumoro, Andri Cahyo; Amalia, Rizka; Budiyati, Catarina Sri; Retnowati, Diah Susetyo; Ratnawati, Ratnawati

    2015-10-01

    In addition to the presence of antinutrients, the inferior physicochemical properties of flours has caused gadung (Dioscorea hispida dennst) becomes one of the underutilized tubers in the world. Acetylation is one of the starch modification methods to alter the physicochemical properties of starch, namely swelling power and solubility. The objective of this work was to investigate the effect of reaction time, glacial acetic acid/flour mass ratio and pH on gadung flour acetylation at ambient temperature. The acetylation was carried out by reacting gadung flour slurry of 20 % consistency with glacial acetic acid under alkaline condition. The results show that in general degree of substitution and swelling power increased with the increase of reaction time, while the solubility was not affected by reaction time after 10 min acetylation. Acetylation led to significant changes in morphology and structure of gadung flour starch granules. Overall, all the acetylated gadung flours obtained in this work were having higher swelling power and solubility than the native flour. Acetylation of gadung flour using glacial acetic acid with 1:3 mass ratio and pH 8.0 at ambient temperature for 30 min resulted gadung flours with swelling power and solubility similar to that of Korean wheat flour. PMID:26396408

  11. Atmospheric geochemistry of formic and acetic acids at a mid-latitude temperate site

    NASA Technical Reports Server (NTRS)

    Talbot, R. W.; Beecher, K. M.; Harriss, R. C.; Cofer, R. W., III

    1988-01-01

    Tropospheric concentrations of formic and acetic acids in the gas, the aerosol, and the rainwater phases were determined in samples collected 1-2 m above ground level at an open field site in eastern Virginia. These acids were found to occur principally (98 percent or above) in the gas phase, with a marked annual seasonality, averaging 1890 ppt for formate and 1310 ppt for acetate during the growing season, as compared to 695 ppt and 700 ppt, respectively, over the nongrowing season. The data support the hypothesis that biogenic emissions from vegatation are important sources of atmospheric formic and acetic acid during the local growing season. The same time trends were observed for precipitation, although with less defined seasonality. The relative increase of the acetic acid/formic acid ratio during the nongrowing season points to the dominance of anthropogenic inputs of acetic acid from motor vehicles and biomass combustion in the wintertime.

  12. Permeability of acetic acid through organic films at the air-aqueous interface.

    PubMed

    Gilman, Jessica B; Vaida, Veronica

    2006-06-22

    Recent field studies of collected aerosol particles, both marine and continental, show that the outermost layers contain long-chain (C >or= 18) organics. The presence of these long-chain organics could impede the transport of gases and other volatile species across the interface. This could effect the particle's composition, lifetime, and heterogeneous chemistry. In this study, the uptake rate of acetic acid vapor across a clean interface and through films of long-chain organics into an aqueous subphase solution containing an acid-base indicator (bromocresol green) was measured under ambient conditions using visible absorption spectroscopy. Acetic acid is a volatile organic compound (VOC) and is an atmospherically relevant organic acid. The uptake of acetic acid through single-component organic films of 1-octadecanol (C(18)H(38)O), 1-triacontanol (C(30)H(62)O), cis-9-octadecen-1-ol (C(18)H(36)O), and nonacosane (C(29)H(60)) in addition to two mixed films containing equimolar 1-triacontanol/nonacosane and equimolar 1-triacontanol/cis-9-octadecen-1-ol was determined. These species represent long-chain organic compounds that reside at the air-aqueous interface of atmospheric aerosols. The cis-9-octadecen-1-ol film had little effect on the net uptake rate of acetic acid vapor into solution; however, the uptake rate was reduced by almost one-half by an interfacial film of 1-triacontanol. The measured uptake rates were used to calculate the permeability of acetic acid through the various films which ranged from 1.5 x 10(-3) cm s(-1) for 1-triacontanol, the least permeable film, to 2.5 x 10(-2) cm s(-1) for cis-9-octadecen-1-ol, the most permeable film. Both mixed films had permeabilities that were between that of the single-component films comprising the mixture. This shows that the permeability of a mixed film may not be solely determined by the most permeable species in the mixture. The permeabilities of all the films studied here are discussed in relation to their

  13. Phenyl Acetate Preparation from Phenol and Acetic Acid: Reassessment of a Common Textbook Misconception.

    ERIC Educational Resources Information Center

    Hocking, M. B.

    1980-01-01

    Reassesses a common textbook misconception that "...phenols cannot be esterified directly." Results of experiments are discussed and data tables provided of an effective method for the direct preparation of phenyl acetate. (CS)

  14. Improved isolation of zein from corn gluten meal using acetic acid as solvent

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To develop new uses for corn zein, an improved means of isolating zein is needed. We have evaluated the ability of acetic acid to remove zein from corn gluten meal, distillers dried grains and ground corn. Acetic acid removed zein more quickly, at lower temperatures and in higher yields when compa...

  15. Microbiological preservation of cucumbers for bulk storage by the use of acetic acid and food preservatives

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Microbial growth did not occur when cucumbers were preserved without a thermal process by storage in solutions containing acetic acid, sodium benzoate, and calcium chloride to maintain tissue firmness. The concentrations of acetic acid and sodium benzoate required to assure preservation were low en...

  16. 2-[4-(Carb­oxy­meth­yl)phen­oxy]acetic acid

    PubMed Central

    Fu, Jun-Dan; Wen, Yi-Hang

    2011-01-01

    The title compound, C10H10O5, was obtained by the reaction of 4-hy­droxy­phenyl­acetic acid with chloro­acetic acid. In the crystal, the mol­ecules form a three-dimensional network by way of inter­molecular O—H⋯O hydrogen bonding. PMID:21522674

  17. Development of xylose-fermenting yeasts for ethanol production at high acetic acid concentrations

    SciTech Connect

    Mohandas, D.V.; Whelan, D.R.; Panchal, C.J.

    1995-12-31

    Mutants resistant to comparatively high levels of acetic acid were isolated from the xylose-fermenting yeasts Candida shehatae and Pichia Stipitis by adapting these cultures to increasing concentrations of acetic acid grown in shake-flask cultures. These mutants were tested for their ability to ferment xylose in presence of high acetic acid concentrations, in acid hydrolysates of wood, and in hardwood spent sulfite liquor, and compared with their wild-type counterparts and between themselves. The P. stipitis mutant exhibited faster fermentation times, better tolerance to acid hydrolysates, and tolerance to lower pH.

  18. MOF-Derived Tungstated Zirconia as Strong Solid Acids toward High Catalytic Performance for Acetalization.

    PubMed

    Wang, Peng; Feng, Jian; Zhao, Yupei; Wang, Shaobin; Liu, Jian

    2016-09-14

    A strong solid acid, tungstated zirconia (WZ), has been prepared first using tungstate immobilized UiO-66 as precursors through a "double-solvent" impregnation method under mild calcination temperature. With moderate W contents, the as-synthesized WZ catalysts possess a high density of acid sites, and the proper heat treatment also has facilely led to a bunch of oligomeric tungsten clusters on stabilized tetragonal ZrO2. The resultant solid acids show an improved catalytic performance toward the benzaldehyde's acetalization in comparison with traditional zirconium hydroxide-prepared WZ. Notably, due to large surface area and additionally introduced strong acid sites, the MOF-derived WZ catalysts afforded conversion up to 86.0%. The facile method endows the WZ catalysts with superior catalytic activities and excellent recyclability, thus opening a new avenue for preparation of metal oxide-based solid superacids and superbases. PMID:27557351

  19. Synthesis of acetic acid via methanol hydrocarboxylation with CO2 and H2

    PubMed Central

    Qian, Qingli; Zhang, Jingjing; Cui, Meng; Han, Buxing

    2016-01-01

    Acetic acid is an important bulk chemical that is currently produced via methanol carbonylation using fossil based CO. Synthesis of acetic acid from the renewable and cheap CO2 is of great importance, but state of the art routes encounter difficulties, especially in reaction selectivity and activity. Here we report a route to produce acetic acid from CO2, methanol and H2. The reaction can be efficiently catalysed by Ru–Rh bimetallic catalyst using imidazole as the ligand and LiI as the promoter in 1,3-dimethyl-2-imidazolidinone (DMI) solvent. It is confirmed that methanol is hydrocarboxylated into acetic acid by CO2 and H2, which accounts for the outstanding reaction results. The reaction mechanism is proposed based on the control experiments. The strategy opens a new way for acetic acid production and CO2 transformation, and represents a significant progress in synthetic chemistry. PMID:27165850

  20. Synthesis of acetic acid via methanol hydrocarboxylation with CO2 and H2.

    PubMed

    Qian, Qingli; Zhang, Jingjing; Cui, Meng; Han, Buxing

    2016-01-01

    Acetic acid is an important bulk chemical that is currently produced via methanol carbonylation using fossil based CO. Synthesis of acetic acid from the renewable and cheap CO2 is of great importance, but state of the art routes encounter difficulties, especially in reaction selectivity and activity. Here we report a route to produce acetic acid from CO2, methanol and H2. The reaction can be efficiently catalysed by Ru-Rh bimetallic catalyst using imidazole as the ligand and LiI as the promoter in 1,3-dimethyl-2-imidazolidinone (DMI) solvent. It is confirmed that methanol is hydrocarboxylated into acetic acid by CO2 and H2, which accounts for the outstanding reaction results. The reaction mechanism is proposed based on the control experiments. The strategy opens a new way for acetic acid production and CO2 transformation, and represents a significant progress in synthetic chemistry. PMID:27165850

  1. The Key to Acetate: Metabolic Fluxes of Acetic Acid Bacteria under Cocoa Pulp Fermentation-Simulating Conditions

    PubMed Central

    Adler, Philipp; Frey, Lasse Jannis; Berger, Antje; Bolten, Christoph Josef; Hansen, Carl Erik

    2014-01-01

    Acetic acid bacteria (AAB) play an important role during cocoa fermentation, as their main product, acetate, is a major driver for the development of the desired cocoa flavors. Here, we investigated the specialized metabolism of these bacteria under cocoa pulp fermentation-simulating conditions. A carefully designed combination of parallel 13C isotope labeling experiments allowed the elucidation of intracellular fluxes in the complex environment of cocoa pulp, when lactate and ethanol were included as primary substrates among undefined ingredients. We demonstrate that AAB exhibit a functionally separated metabolism during coconsumption of two-carbon and three-carbon substrates. Acetate is almost exclusively derived from ethanol, while lactate serves for the formation of acetoin and biomass building blocks. Although this is suboptimal for cellular energetics, this allows maximized growth and conversion rates. The functional separation results from a lack of phosphoenolpyruvate carboxykinase and malic enzymes, typically present in bacteria to interconnect metabolism. In fact, gluconeogenesis is driven by pyruvate phosphate dikinase. Consequently, a balanced ratio of lactate and ethanol is important for the optimum performance of AAB. As lactate and ethanol are individually supplied by lactic acid bacteria and yeasts during the initial phase of cocoa fermentation, respectively, this underlines the importance of a well-balanced microbial consortium for a successful fermentation process. Indeed, AAB performed the best and produced the largest amounts of acetate in mixed culture experiments when lactic acid bacteria and yeasts were both present. PMID:24837393

  2. Effective Trapping of Fruit Flies with Cultures of Metabolically Modified Acetic Acid Bacteria

    PubMed Central

    Ishii, Yuri; Akasaka, Naoki; Goda, Itsuko; Sakoda, Hisao

    2015-01-01

    Acetoin in vinegar is an attractant to fruit flies when combined with acetic acid. To make vinegar more effective in attracting fruit flies with increased acetoin production, Komagataeibacter europaeus KGMA0119 was modified by specific gene disruption of the acetohydroxyacid isomeroreductase gene (ilvC). A previously constructed mutant lacking the putative ligand-sensing region in the leucine-responsive regulatory protein (KeLrp, encoded by Kelrp) was also used. The ilvC and Kelrp disruptants (KGMA5511 and KGMA7203, respectively) produced greater amounts of acetoin (KGMA5511, 0.11%; KGMA7203, 0.13%) than the wild-type strain KGMA0119 (0.069%). KGMA7203 produced a trace amount of isobutyric acid (0.007%), but the other strains did not. These strains produced approximately equal amounts of acetic acid (0.7%). The efficiency of fruit fly attraction was investigated with cultured Drosophila melanogaster. D. melanogaster flies (approximately 1,500) were released inside a cage (2.5 m by 2.5 m by 1.5 m) and were trapped with a device containing vinegar and a sticky sheet. The flies trapped on the sticky sheet were counted. The cell-free supernatant from KGMA7203 culture captured significantly more flies (19.36 to 36.96% of released flies) than did KGMA0119 (3.25 to 11.40%) and KGMA5511 (6.87 to 21.50%) cultures. Contrastingly, a 0.7% acetic acid solution containing acetoin (0.13%) and isobutyric acid (0.007%), which mimicked the KGMA7203 supernatant, captured significantly fewer flies (0.88 to 4.57%). Furthermore, the KGMA0119 supernatant with additional acetoin (0.13%) and isobutyric acid (0.007%) captured slightly more flies than the original KGMA0119 supernatant but fewer than the KGMA7203 supernatant, suggesting that the synergistic effects of acetic acid, acetoin, isobutyric acid, and unidentified metabolites achieved the efficient fly trapping of the KGMA7203 supernatant. PMID:25595769

  3. Acetic acid chromoendoscopy: Improving neoplasia detection in Barrett's esophagus

    PubMed Central

    Chedgy, Fergus J Q; Subramaniam, Sharmila; Kandiah, Kesavan; Thayalasekaran, Sreedhari; Bhandari, Pradeep

    2016-01-01

    Barrett’s esophagus (BE) is an important condition given its significant premalignant potential and dismal five-year survival outcomes of advanced esophageal adenocarcinoma. It is therefore suggested that patients with a diagnosis of BE undergo regular surveillance in order to pick up dysplasia at an earlier stage to improve survival. Current “gold-standard” surveillance protocols suggest targeted biopsy of visible lesions followed by four quadrant random biopsies every 2 cm. However, this method of Barrett’s surveillance is fraught with poor endoscopist compliance as the procedures are time consuming and poorly tolerated by patients. There are also significant miss-rates with this technique for the detection of neoplasia as only 13% of early neoplastic lesions appear as visible nodules. Despite improvements in endoscope resolution these problems persist. Chromoendoscopy is an extremely useful adjunct to enhance mucosal visualization and characterization of Barrett’s mucosa. Acetic acid chromoendoscopy (AAC) is a simple, non-proprietary technique that can significantly improve neoplasia detection rates. This topic highlight summarizes the current evidence base behind AAC for the detection of neoplasia in BE and provides an insight into the direction of travel for further research in this area. PMID:27433088

  4. Antifertility mechanisms of gossypol acetic acid in female rats.

    PubMed

    Yang, Y Q; Wu, X Y

    1987-07-01

    Gossypol acetic acid was administered orally (30, 60, 90 and 120 mg/kg/day) on Days 1-5 post coitum to mature female rats. At autopsy on Day 10, pregnancy in most treated animals (6/7 and 6/8) was blocked at high doses (90 and 120 mg/kg/day respectively). As the daily dose decreased to 60 mg/kg/day half (4/8) were not pregnant. However, at a lower dose (30 mg/kg/day), or at a single dose of 200 mg/kg at Day 1 p.c., pregnancy was not blocked. The concentrations of progesterone in the serum of these females were significantly decreased except at the low dose. The numbers of implantation sites in the treated females that did remain pregnant were similar to those in control females except at the dose of 120 mg/kg/day. Gossypol did not retard the development of the preimplantation embryo or cavitation. The Pontamine Blue test revealed that the drug did not interfere with the initiation of implantation. We suggest that gossypol has an antifertility effect in the female rat because it is luteolytic and disrupts post-implantation development. PMID:3656277

  5. Metabolism of Flavone-8-acetic Acid in Mice.

    PubMed

    Pham, Minh Hien; Auzeil, Nicolas; Regazzetti, Anne; Scherman, Daniel; Seguin, Johanne; Mignet, Nathalie; Dauzonne, Daniel; Chabot, Guy G

    2016-08-01

    Flavone-8-acetic acid (FAA) is a potent antivascular agent in mice but not in humans. Assuming that FAA was bioactivated in mice, we previously demonstrated that 6-OH-FAA was formed from FAA by mouse microsomes but not by human microsomes; its antivascular activity was 2.1- to 15.9-fold stronger than that of FAA, and its antivascular activity was mediated through the Ras homolog gene family (Rho) protein kinase A (RhoA) pathway. The present work aimed to study FAA metabolism in order to verify if 6-OH-FAA is formed in mice. Using synthesized standards and high-performance liquid chromatography (HPLC) coupled with ultraviolet (UV) detection and mass spectrometry (MS) analysis, we herein demonstrated, for the first time, that in vitro FAA and its monohydroxylated derivatives could directly undergo phase II metabolism forming glucuronides, and two FAA epoxides were mostly scavenged by NAC and GSH forming corresponding adducts. FAA was metabolized in mice. Several metabolites were formed, in particular 6-OHFAA. The antitumor activity of 6-OH-FAA in vivo is worthy of investigation. PMID:27466491

  6. Metabolic regulation of the plant hormone indole-3-acetic acid

    SciTech Connect

    Jerry D. Cohen

    2009-11-01

    The phytohormone indole-3-acetic acid (IAA, auxin) is important for many aspects of plant growth, development and responses to the environment yet the routes to is biosynthesis and mechanisms for regulation of IAA levels remain important research questions. A critical issue concerning the biosynthesis if IAA in plants is that redundant pathways for IAA biosynthesis exist in plants. We showed that these redundant pathways and their relative contribution to net IAA production are under both developmental and environmental control. We worked on three fundamental problems related to how plants get their IAA: 1) An in vitro biochemical approach was used to define the tryptophan dependent pathway to IAA using maize endosperm, where relatively large amounts of IAA are produced over a short developmental period. Both a stable isotope dilution and a protein MS approach were used to identify intermediates and enzymes in the reactions. 2) We developed an in vitro system for analysis of tryptophan-independent IAA biosynthesis in maize seedlings and we used a metabolite profiling approach to isolate intermediates in this reaction. 3) Arabidopsis contains a small family of genes that encode potential indolepyruvate decarboxylase enzymes. We cloned these genes and studied plants that are mutant in these genes and that over-express each member in the family in terms of the level and route of IAA biosynthesis. Together, these allowed further development of a comprehensive picture of the pathways and regulatory components that are involved in IAA homeostasis in higher plants.

  7. Acetic acid chromoendoscopy: Improving neoplasia detection in Barrett's esophagus.

    PubMed

    Chedgy, Fergus J Q; Subramaniam, Sharmila; Kandiah, Kesavan; Thayalasekaran, Sreedhari; Bhandari, Pradeep

    2016-07-01

    Barrett's esophagus (BE) is an important condition given its significant premalignant potential and dismal five-year survival outcomes of advanced esophageal adenocarcinoma. It is therefore suggested that patients with a diagnosis of BE undergo regular surveillance in order to pick up dysplasia at an earlier stage to improve survival. Current "gold-standard" surveillance protocols suggest targeted biopsy of visible lesions followed by four quadrant random biopsies every 2 cm. However, this method of Barrett's surveillance is fraught with poor endoscopist compliance as the procedures are time consuming and poorly tolerated by patients. There are also significant miss-rates with this technique for the detection of neoplasia as only 13% of early neoplastic lesions appear as visible nodules. Despite improvements in endoscope resolution these problems persist. Chromoendoscopy is an extremely useful adjunct to enhance mucosal visualization and characterization of Barrett's mucosa. Acetic acid chromoendoscopy (AAC) is a simple, non-proprietary technique that can significantly improve neoplasia detection rates. This topic highlight summarizes the current evidence base behind AAC for the detection of neoplasia in BE and provides an insight into the direction of travel for further research in this area. PMID:27433088

  8. Acetic acid bacteria isolated from grapes of South Australian vineyards.

    PubMed

    Mateo, E; Torija, M J; Mas, A; Bartowsky, E J

    2014-05-16

    Acetic acid bacteria (AAB) diversity from healthy, mould-infected and rot-affected grapes collected from three vineyards of Adelaide Hills (South Australia) was analyzed by molecular typing and identification methods. Nine different AAB species were identified from the 624 isolates recovered: Four species from Gluconobacter genus, two from Asaia and one from Acetobacter were identified by the analysis of 16S rRNA gene and 16S-23S rRNA gene internal transcribed spacer. However, the identification of other isolates that were assigned as Asaia sp. and Ameyamaea chiangmaiensis required more analysis for a correct species classification. The species of Gluconobacter cerinus was the main one identified; while one genotype of Asaia siamensis presented the highest number of isolates. The number of colonies recovered and genotypes identified was strongly affected by the infection status of the grapes; the rot-affected with the highest number. However, the species diversity was similar in all the cases. High AAB diversity was detected with a specific genotype distribution for each vineyard. PMID:24681711

  9. Design, Synthesis, and Antimycobacterial Activity of Novel Theophylline-7-Acetic Acid Derivatives With Amino Acid Moieties.

    PubMed

    Stavrakov, Georgi; Valcheva, Violeta; Voynikov, Yulian; Philipova, Irena; Atanasova, Mariyana; Konstantinov, Spiro; Peikov, Plamen; Doytchinova, Irini

    2016-03-01

    The theophylline-7-acetic acid (7-TAA) scaffold is a promising novel lead compound for antimycobacterial activity. Here, we derive a model for antitubercular activity prediction based on 14 7-TAA derivatives with amino acid moieties and their methyl esters. The model is applied to a combinatorial library, consisting of 40 amino acid and methyl ester derivatives of 7-TAA. The best three predicted compounds are synthesized and tested against Mycobacterium tuberculosis H37Rv. All of them are stable, non-toxic against human cells and show antimycobacterial activity in the nanomolar range being 60 times more active than ethambutol. PMID:26502828

  10. Removal and recovery of furfural, 5-hydroxymethylfurfural, and acetic acid from aqueous solutions using a soluble polyelectrolyte.

    PubMed

    Carter, Brian; Gilcrease, Patrick C; Menkhaus, Todd J

    2011-09-01

    In the cellulosic ethanol process, furfural, 5-hydroxymethylfurfural (HMF), and acetic acid are formed during the high temperature acidic pretreatment step needed to convert biomass into fermentable sugars. These compounds can inhibit cellulase enzymes and fermentation organisms at relatively low concentrations (≥ 1 g/L). Effective removal of these inhibitory compounds would allow the use of more severe pretreatment conditions to improve sugar yields and lead to more efficient fermentations; if recovered and purified, they could also be sold as valuable by-products. This study investigated the separation of aldhehydes (furfural and HMF) and organic acid (acetic acid) inhibitory compounds from simple aqueous solutions by using polyethyleneimene (PEI), a soluble cationic polyelectrolyte. PEI added to simple solutions of each inhibitor at a ratio of 1 mol of functional group to 1 mol inhibitor removed up to 89.1, 58.6, and 81.5 wt% of acetic acid, HMF, and furfural, respectively. Furfural and HMF were recovered after removal by washing the polyelectrolyte/inhibitor complex with dilute sulfuric acid solution. Recoveries up to 81.0 and 97.0 wt% were achieved for furfural and HMF, respectively. The interaction between PEI and acetic acid was easily disrupted by the addition of chloride ions, sulfate ions, or hydroxide ions. The use of soluble polymers for the removal and recovery of inhibitory compounds from biomass slurries is a promising approach to enhance the efficiency and economics of an envisioned biorefinery. PMID:21455937

  11. Acetic acid suppresses the increase in disaccharidase activity that occurs during culture of caco-2 cells.

    PubMed

    Ogawa, N; Satsu, H; Watanabe, H; Fukaya, M; Tsukamoto, Y; Miyamoto, Y; Shimizu, M

    2000-03-01

    To understand how blood glucose level is lowered by oral administration of vinegar, we examined effects of acetic acid on glucose transport and disaccharidase activity in Caco-2 cells. Cells were cultured for 15 d in a medium containing 5 mmol/L of acetic acid. This chronic treatment did not affect cell growth or viability, and furthermore, apoptotic cell death was not observed. Glucose transport, evaluated with a nonmetabolizable substrate, 3-O-methyl glucose, also was not affected. However, the increase of sucrase activity observed in control cells (no acetic acid) was significantly suppressed by acetic acid (P < 0.01). Acetic acid suppressed sucrase activity in concentration- and time-dependent manners. Similar treatments (5 mmol/L and 15 d) with other organic acids such as citric, succinic, L-maric, L-lactic, L-tartaric and itaconic acids, did not suppress the increase in sucrase activity. Acetic acid treatment (5 mmol/L and 15 d) significantly decreased the activities of disaccharidases (sucrase, maltase, trehalase and lactase) and angiotensin-I-converting enzyme, whereas the activities of other hydrolases (alkaline phosphatase, aminopeptidase-N, dipeptidylpeptidase-IV and gamma-glutamyltranspeptidase) were not affected. To understand mechanisms underlying the suppression of disaccharidase activity by acetic acid, Northern and Western analyses of the sucrase-isomaltase complex were performed. Acetic acid did not affect the de novo synthesis of this complex at either the transcriptional or translational levels. The antihyperglycemic effect of acetic acid may be partially due to the suppression of disaccharidase activity. This suppression seems to occur during the post-translational processing. PMID:10702577

  12. Sol-gel process for preparation of YBa{sub 2}Cu{sub 4}O{sub 8} from acidic acetates/ammonia/ascorbic acid systems

    SciTech Connect

    Deptula, A.; Lada, W.; Olczak, T.; Goretta, K.C.; Bartolomeo, A.; Casadio, S.

    1997-03-01

    YBa{sub 2}Cu{sub 4}O{sub x} sols were prepared by addition of ammonia to acidic acetate solutions of Y{sup 3+}, Ba{sup 2+}, and Cu{sup 2+}. Ascorbic acid was added to part of the sol. The resultant sols were gelled to a shard or a coating by evaporation at 60 C. Addition of ethanol to the sols facilitated formation of gel coatings, fabricated by a dipping technique, on Ag or glass or substrates. At 100 C, gels formed in the presence of ascorbic acid were perfectly amorphous, in contrast to crystalline acetate gels. The quality of coatings prepared from ascorbate gels was superior to that of acetate gel coatings.

  13. Microbial process for the preparation of acetic acid, as well as solvent for its extraction from the fermentation broth

    DOEpatents

    Gaddy, James L.; Clausen, Edgar C.; Ko, Ching-Whan; Wade, Leslie E.; Wikstrom, Carl V.

    2004-06-22

    A modified water-immiscible solvent useful in the extraction of acetic acid from aqueous streams is a substantially pure mixture of isomers of highly branched di-alkyl amines. Solvent mixtures formed of such a modified solvent with a desired co-solvent, preferably a low boiling hydrocarbon, are useful in the extraction of acetic acid from aqueous gaseous streams. An anaerobic microbial fermentation process for the production of acetic acid employs such solvents, under conditions which limit amide formation by the solvent and thus increase the efficiency of acetic acid recovery. Methods for the direct extraction of acetic acid and the extractive fermentation of acetic acid also employ the modified solvents and increase efficiency of acetic acid production. Such increases in efficiency are also obtained where the energy source for the microbial fermentation contains carbon dioxide and the method includes a carbon dioxide stripping step prior to extraction of acetic acid in solvent.

  14. Microbial process for the preparation of acetic acid, as well as solvent for its extraction from the fermentation broth

    DOEpatents

    Gaddy, James L.; Clausen, Edgar C.; Ko, Ching-Whan; Wade, Leslie E.; Wikstrom, Carl V.

    2007-03-27

    A modified water-immiscible solvent useful in the extraction of acetic acid from aqueous streams is a substantially pure mixture of isomers of highly branched di-alkyl amines. Solvent mixtures formed of such a modified solvent with a desired co-solvent, preferably a low boiling hydrocarbon, are useful in the extraction of acetic acid from aqueous gaseous streams. An anaerobic microbial fermentation process for the production of acetic acid employs such solvents, under conditions which limit amide formation by the solvent and thus increase the efficiency of acetic acid recovery. Methods for the direct extraction of acetic acid and the extractive fermentation of acetic acid also employ the modified solvents and increase efficiency of acetic acid production. Such increases in efficiency are also obtained where the energy source for the microbial fermentation contains carbon dioxide and the method includes a carbon dioxide stripping step prior to extraction of acetic acid in solvent.

  15. Effects of acetic acid on the viability of Ascaris lumbricoides eggs

    PubMed Central

    Beyhan, Yunus E.; Yilmaz, Hasan; Hokelek, Murat

    2016-01-01

    Objectives: To investigate the effects of acetic acid on durable Ascaris lumbricoides (A. lumbricoides) eggs to determine the effective concentration of vinegar and the implementation period to render the consumption of raw vegetables more reliable. Methods: This experimental study was performed in May 2015 in the Parasitology Laboratory, Faculty of Medicine, Yuzuncu Yil University, Van, Turkey. The A. lumbricoides eggs were divided into 2 groups. Eggs in the study group were treated with 1, 3, 5, and 10% acetic acid concentrations, and eggs in the control group were treated with Eosin. The eggs’ viability was observed at the following points in time during the experiment: 0, 10, 15, 20, 30, 45, and 60 minutes. Results: The 1% acetic acid was determined insufficient on the viability of Ascaris eggs. At the 30th minute, 3% acetic acid demonstrated 95% effectiveness, and at 5% concentration, all eggs lost their viability. Treatment of acetic acid at the ratio of 4.8% in 30 minutes, or a ratio of 4.3% in 60 minutes is required for full success of tretment. Conclusion: Since Ascaris eggs have 3 layers and are very resistant, the acetic acid concentration, which can be effective on these eggs are thought to be effective also on many other parasitic agents. In order to attain an active protection, after washing the vegetables, direct treatment with a vinegar containing 5% acetic acid for 30 minutes is essential. PMID:26905351

  16. Acetic acid bacteria in traditional balsamic vinegar: phenotypic traits relevant for starter cultures selection.

    PubMed

    Gullo, Maria; Giudici, Paolo

    2008-06-30

    This review focuses on acetic acid bacteria in traditional balsamic vinegar process. Although several studies are available on acetic acid bacteria ecology, metabolism and nutritional requirements, their activity as well as their technological traits in homemade vinegars as traditional balsamic vinegar is not well known. The basic technology to oxidise cooked grape must to produce traditional balsamic vinegar is performed by the so called "seed-vinegar" that is a microbiologically undefined starter culture obtained from spontaneous acetification of previous raw material. Selected starter cultures are the main technological improvement in order to innovate traditional balsamic vinegar production but until now they are rarely applied. To develop acetic acid bacteria starter cultures, selection criteria have to take in account composition of raw material, acetic acid bacteria metabolic activities, applied technology and desired characteristics of the final product. For traditional balsamic vinegar, significative phenotypical traits of acetic acid bacteria have been highlighted. Basic traits are: ethanol preferred and efficient oxidation, fast rate of acetic acid production, tolerance to high concentration of acetic acid, no overoxidation and low pH resistance. Specific traits are tolerance to high sugar concentration and to a wide temperature range. Gluconacetobacter europaeus and Acetobacter malorum strains can be evaluated to develop selected starter cultures since they show one or more suitable characters. PMID:18177968

  17. Indole-3-Acetic Acid Biosynthesis in Colletotrichum gloeosporioides f. sp. aeschynomene

    PubMed Central

    Robinson, M.; Riov, J.; Sharon, A.

    1998-01-01

    We characterized the biosynthesis of indole-3-acetic acid by the mycoherbicide Colletotrichum gloeosporioides f. sp. aeschynomene. Auxin production was tryptophan dependent. Compounds from the indole-3-acetamide and indole-3-pyruvic acid pathways were detected in culture filtrates. Feeding experiments and in vitro assay confirmed the presence of both pathways. Indole-3-acetamide was the major pathway utilized by the fungus to produce indole-3-acetic acid in culture. PMID:9835603

  18. Effects of acetic acid and lactic acid on the growth of Saccharomyces cerevisiae in a minimal medium.

    PubMed

    Narendranath, N V; Thomas, K C; Ingledew, W M

    2001-03-01

    Specific growth rates (mu) of two strains of Saccharomyces cerevisiae decreased exponentially (R2 > 0.9) as the concentrations of acetic acid or lactic acid were increased in minimal media at 30 degrees C. Moreover, the length of the lag phase of each growth curve (h) increased exponentially as increasing concentrations of acetic or lactic acid were added to the media. The minimum inhibitory concentration (MIC) of acetic acid for yeast growth was 0.6% w/v (100 mM) and that of lactic acid was 2.5% w/v (278 mM) for both strains of yeast. However, acetic acid at concentrations as low as 0.05-0.1% w/v and lactic acid at concentrations of 0.2-0.8% w/v begin to stress the yeasts as seen by reduced growth rates and decreased rates of glucose consumption and ethanol production as the concentration of acetic or lactic acid in the media was raised. In the presence of increasing acetic acid, all the glucose in the medium was eventually consumed even though the rates of consumption differed. However, this was not observed in the presence of increasing lactic acid where glucose consumption was extremely protracted even at a concentration of 0.6% w/v (66 mM). A response surface central composite design was used to evaluate the interaction between acetic and lactic acids on the specific growth rate of both yeast strains at 30 degrees C. The data were analysed using the General Linear Models (GLM) procedure. From the analysis, the interaction between acetic acid and lactic acid was statistically significant (P < or = 0.001), i.e., the inhibitory effect of the two acids present together in a medium is highly synergistic. PMID:11420658

  19. Biosynthesis of the Halogenated Auxin, 4-Chloroindole-3-Acetic Acid1[W][OA

    PubMed Central

    Tivendale, Nathan D.; Davidson, Sandra E.; Davies, Noel W.; Smith, Jason A.; Dalmais, Marion; Bendahmane, Abdelhafid I.; Quittenden, Laura J.; Sutton, Lily; Bala, Raj K.; Le Signor, Christine; Thompson, Richard; Horne, James; Reid, James B.; Ross, John J.

    2012-01-01

    Seeds of several agriculturally important legumes are rich sources of the only halogenated plant hormone, 4-chloroindole-3-acetic acid. However, the biosynthesis of this auxin is poorly understood. Here, we show that in pea (Pisum sativum) seeds, 4-chloroindole-3-acetic acid is synthesized via the novel intermediate 4-chloroindole-3-pyruvic acid, which is produced from 4-chlorotryptophan by two aminotransferases, TRYPTOPHAN AMINOTRANSFERASE RELATED1 and TRYPTOPHAN AMINOTRANSFERASE RELATED2. We characterize a tar2 mutant, obtained by Targeting Induced Local Lesions in Genomes, the seeds of which contain dramatically reduced 4-chloroindole-3-acetic acid levels as they mature. We also show that the widespread auxin, indole-3-acetic acid, is synthesized by a parallel pathway in pea. PMID:22573801

  20. Acetic Acid Acts as a Volatile Signal To Stimulate Bacterial Biofilm Formation

    PubMed Central

    Chen, Yun; Gozzi, Kevin; Yan, Fang

    2015-01-01

    ABSTRACT Volatiles are small air-transmittable chemicals with diverse biological activities. In this study, we showed that volatiles produced by the bacterium Bacillus subtilis had a profound effect on biofilm formation of neighboring B. subtilis cells that grew in proximity but were physically separated. We further demonstrated that one such volatile, acetic acid, is particularly potent in stimulating biofilm formation. Multiple lines of genetic evidence based on B. subtilis mutants that are defective in either acetic acid production or transportation suggest that B. subtilis uses acetic acid as a metabolic signal to coordinate the timing of biofilm formation. Lastly, we investigated how B. subtilis cells sense and respond to acetic acid in regulating biofilm formation. We showed the possible involvement of three sets of genes (ywbHG, ysbAB, and yxaKC), all encoding putative holin-antiholin-like proteins, in cells responding to acetic acid and stimulating biofilm formation. All three sets of genes were induced by acetate. A mutant with a triple mutation of those genes showed a severe delay in biofilm formation, whereas a strain overexpressing ywbHG showed early and robust biofilm formation. Results of our studies suggest that B. subtilis and possibly other bacteria use acetic acid as a metabolic signal to regulate biofilm formation as well as a quorum-sensing-like airborne signal to coordinate the timing of biofilm formation by physically separated cells in the community. PMID:26060272

  1. First chemoenzymatic synthesis of (+)-2-carboxypyrrolidine-3-acetic acid, the nucleus of kainoid amino acids.

    PubMed

    Felluga, Fulvia; Forzato, Cristina; Nitti, Patrizia; Pitacco, Giuliana; Ghelfi, Franco; Valentin, Ennio

    2012-02-01

    The distinctive nucleus of kainoid amino acids, (2S,3R)-(+)-2-carboxypyrrolidine-3-acetic acid 6, was synthesized by a chemoenzymatic process, exploiting the diastereomeric cis/trans methyl pyroglutamate derivatives 10a-c/11a-c as key intermediates. These mixtures, when subjected to a kinetic resolution mediated by α-chymotrypsin, reacted diastereo-, regio-, and enantioselectively to give the trans derivatives (+)-10a-c possessing the correct (2S,3R) configuration. Subsequently, the desired product (2S,3R)-(+)-6 could be obtained after well-established transformations. PMID:22180179

  2. Effect of exogenous indole-3-acetic acid and naphthalene acetic acid on regeneration of damask rose cuttings in three growing media.

    PubMed

    Khan, Rahmat Ullah; Khan, Muhammad Sohail; Rashid, Abdur; Farooq, Arshad

    2007-10-15

    An experiment was conducted to evaluate the performance of various levels of indole-3-acetic acid (IAA) and naphthalene acetic acid (NAA) treatments i.e., 0, 25, 50, 75, 100 mg L(-1) on the regeneration of damask rose (Rosa damascena Mill.) cuttings in different growing media at the research farm of Arid Zone Research Institute D.I. Khan during 2004. The data revealed significant effect of different levels of growth regulators and growing media on the rose establishment parameters viz., plant height, plant spread, number of primary shoots, secondary shoots and survival percentage. Maximum plant height (134.2 cm), plant spread (46.3 cm), primary shoots (6.3), secondary shoots (25) and survival percentage (94.72%) were recorded when the rose cuttings were applied with NAA at the rate of 50 mg L(-1). Among the plant growth regulators, Naphthalene Acetic Acid (NAA) was found to be superior to indole-3-acetic acid (IAA) for its stronger effect regarding all parameters. The optimum level of Naphthalene Acetic Acid (NAA) was found in the range of 50 and 75 mg L(-1), while no such conclusion could be drawn for indole-3-acetic acid (IAA) as all growth parameters were linearly increased up to the highest concentrations of IAA i.e., 100 mg L(-1). Regarding growing media, the leaf mould appeared the best in terms of its positive effect on establishment of rose cuttings by giving the maximum plant height (125.1 cm), plant spread (37 cm), primary shoots (5.2), secondary shoots (19.48) and survival percentage (85.67%), followed by soil + leaf mould, while soil media was least effective. PMID:19093472

  3. Indole-3-acetic acid biosynthetic pathways in the basidiomycetous yeast Rhodosporidium paludigenum.

    PubMed

    Nutaratat, Pumin; Srisuk, Nantana; Arunrattiyakorn, Panarat; Limtong, Savitree

    2016-07-01

    Microorganisms produce plant growth regulators, such as auxins, cytokinins and gibberellins, to promote plant growth. Auxins are a group of compounds with an indole ring that have a positive effect on plant growth. Indole-3-acetic acid (IAA) is a plant growth hormone classified as an indole derivative of the auxin family. IAA biosynthesis pathways have been reported and widely studied in several groups of bacteria. Only a few studies on IAA biosynthesis pathways have been conducted in yeast. This study aimed to investigate IAA biosynthesis pathways in a basidiomycetous yeast (Rhodosporidium paludigenum DMKU-RP301). Investigations were performed both with and without a tryptophan supplement. Indole compound intermediates were detected by gas chromatography-mass spectrometry. Indole-3-lactic acid and indole-3-ethanol were found as a result of the enzymatic reduction of indole-3-pyruvic acid and indole-3-acetaldehyde, in IAA biosynthesis via an indole-3-pyruvic acid pathway. In addition, we also found indole-3-pyruvic acid in culture supernatants determined by high-performance liquid chromatography. Identification of tryptophan aminotransferase activity supports indole-3-pyruvic acid-routed IAA biosynthesis in R. paludigenum DMKU-RP301. We hence concluded that R. paludigenum DMKU-RP301 produces IAA through an indole-3-pyruvic acid pathway. PMID:26899734

  4. Auxin Biosynthesis: Are the Indole-3-Acetic Acid and Phenylacetic Acid Biosynthesis Pathways Mirror Images?

    PubMed

    Cook, Sam D; Nichols, David S; Smith, Jason; Chourey, Prem S; McAdam, Erin L; Quittenden, Laura; Ross, John J

    2016-06-01

    The biosynthesis of the main auxin in plants (indole-3-acetic acid [IAA]) has been elucidated recently and is thought to involve the sequential conversion of Trp to indole-3-pyruvic acid to IAA However, the pathway leading to a less well studied auxin, phenylacetic acid (PAA), remains unclear. Here, we present evidence from metabolism experiments that PAA is synthesized from the amino acid Phe, via phenylpyruvate. In pea (Pisum sativum), the reverse reaction, phenylpyruvate to Phe, is also demonstrated. However, despite similarities between the pathways leading to IAA and PAA, evidence from mutants in pea and maize (Zea mays) indicate that IAA biosynthetic enzymes are not the main enzymes for PAA biosynthesis. Instead, we identified a putative aromatic aminotransferase (PsArAT) from pea that may function in the PAA synthesis pathway. PMID:27208245

  5. Responses of Pisum sativum L. to exogenous indole acetic acid application under manganese toxicity.

    PubMed

    Gangwar, Savita; Singh, Vijay Pratap; Maurya, Jagat Narayan

    2011-06-01

    Responses of pea (Pisum sativum L.) seedlings to manganese (50, 100 and 250 μM) and indole acetic acid (10 and 100 μM) treatments were investigated. Single and combined exposure of pea to manganese and 100 μM indole acetic acid decreased root and shoot fresh mass, chlorophyll, carotenoids, protein and nitrogen while ammonium content increased compared to the control. Combined treatment of pea with 250 μM manganese and 100 μM indole acetic acid decreased root and shoot fresh mass by 54% and 51%, chlorophyll and carotenoids by 31% and 26%, root and shoot protein by 47% and 44%, and root and shoot nitrogen by 44% and 40%, respectively. Activities of glutamine synthetase and glutamate synthase were decreased by the exposure of manganese and 100 μM indole acetic acid while glutamate dehydrogenase activity increased. Combined application of 250 μM manganese and 100 μM indole acetic acid decreased root and shoot glutamine synthetase activity by 44% and 39%, and glutamate synthase activity by 39% and 37% while root and shoot glutamate dehydrogenase activity increased by 47% and 42%, respectively compared to the control. In contrast, application of 10 μM indole acetic acid together with manganese decreased the negative impacts of manganese, and promoted seedling growth compared to the manganese treatments alone. This study has shown that 10 μM indole acetic acid protected pea seedlings appreciably from manganese toxicity by regulating ammonium content and the activities of enzymes of ammonium assimilation, while 100 μM of indole acetic acid exhibited opposite response under manganese toxicity. PMID:21516457

  6. The antimicrobial effect of acetic acid--an alternative to common local antiseptics?

    PubMed

    Ryssel, H; Kloeters, O; Germann, G; Schäfer, Th; Wiedemann, G; Oehlbauer, M

    2009-08-01

    Acetic acid has been commonly used in medicine for more than 6000 years for the disinfection of wounds and especially as an antiseptic agent in the treatment and prophylaxis of the plague. The main goal of this study was to prove the suitability of acetic acid, in low concentration of 3%, as a local antiseptic agent, especially for use in salvage procedures in problematic infections caused by organisms such as Proteus vulgaris, Acinetobacter baumannii or Pseudomonas aeruginosa. This study was designed to compare the in vitro antimicrobial effect of acetic acid with those of common local antiseptics such as povidone-iodine 11% (Betaisodona), polyhexanide 0.04% (Lavasept), mafenide 5% and chlohexidine gluconate 1.5% cetrimide 15% (Hibicet). Former studies suggest the bactericidal effect of acetic acid, but these data are very heterogeneous; therefore, a standardised in vitro study was conducted. To cover the typical bacterial spectrum of a burn unit, the following Gram-negative and Gram-positive bacterial strains were tested: Escherichia coli, P. vulgaris, P. aeruginosa, A. baumannii, Enterococcus faecalis, Staphylococcus epidermidis, methicillin-resistant Staphylococcus aureus (MRSA) and beta-haemolytic Streptococcus group A and B. The tests showed excellent bactericidal effect of acetic acid, particularly with problematic Gram-negative bacteria such as P. vulgaris, P. aeruginosa and A. baumannii. The microbiological spectrum of acetic acid is wide, even when tested at a low concentration of 3%. In comparison to our currently used antiseptic solutions, it showed similar - in some bacteria, even better - bactericidal properties. An evaluation of the clinical value of topical application of acetic acid is currently underway. It can be concluded that acetic acid in a concentration of 3% has excellent bactericidal effect and, therefore, seems to be suitable as a local antiseptic agent, but further clinical studies are necessary. PMID:19286325

  7. Continuous Ethanol Production with a Membrane Bioreactor at High Acetic Acid Concentrations

    PubMed Central

    Ylitervo, Päivi; Franzén, Carl Johan; Taherzadeh, Mohammad J.

    2014-01-01

    The release of inhibitory concentrations of acetic acid from lignocellulosic raw materials during hydrolysis is one of the main concerns for 2nd generation ethanol production. The undissociated form of acetic acid can enter the cell by diffusion through the plasma membrane and trigger several toxic effects, such as uncoupling and lowered intracellular pH. The effect of acetic acid on the ethanol production was investigated in continuous cultivations by adding medium containing 2.5 to 20.0 g·L−1 acetic acid at pH 5.0, at a dilution rate of 0.5 h−1. The cultivations were performed at both high (~25 g·L−1) and very high (100–200 g·L−1) yeast concentration by retaining the yeast cells inside the reactor by a cross-flow membrane in a membrane bioreactor. The yeast was able to steadily produce ethanol from 25 g·L−1 sucrose, at volumetric rates of 5–6 g·L−1·h−1 at acetic acid concentrations up to 15.0 g·L−1. However, the yeast continued to produce ethanol also at a concentration of 20 g·L−1 acetic acid but at a declining rate. The study thereby demonstrates the great potential of the membrane bioreactor for improving the robustness of the ethanol production based on lignocellulosic raw materials. PMID:25028956

  8. Dissimilation of Carbon Monoxide to Acetic Acid by Glucose-Limited Cultures of Clostridium thermoaceticum

    PubMed Central

    Martin, Douglas R.; Misra, Arun; Drake, Harold L.

    1985-01-01

    Clostridium thermoaceticum was cultivated in glucose-limited media, and the dissimilation of CO to acetic acid was evaluated. We found that cultures catalyzed the rapid dissimilation of CO to acetic acid and CO2, with the stoichiometry obtained for conversion approximating that predicted from the following reaction: 4CO + 2H2O → CH3CO2H + 2CO2. Growing cultures formed approximately 50 mmol (3 g) of CO-derived acetic acid per liter of culture, with the rate of maximal consumption approximating 9.1 mmol of CO consumed/h per liter of culture. In contrast, resting cells were found not to dissimilate CO to acetic acid. 14CO was incorporated, with equal distribution between the carboxyl and methyl carbons of acetic acid when the initial cultivation gas phase was 100% CO, whereas 14CO2 preferentially entered the carboxyl carbon when the initial gas phase was 100% CO2. Significantly, in the presence of saturating levels of CO, 14CO2 preferentially entered the methyl carbon, whereas saturating levels of CO2 yielded 14CO-derived labeling predominantly in the carboxyl carbon. These findings are discussed in relation to the path of carbon flow to acetic acid. PMID:16346807

  9. Comparison of D-gluconic acid production in selected strains of acetic acid bacteria.

    PubMed

    Sainz, F; Navarro, D; Mateo, E; Torija, M J; Mas, A

    2016-04-01

    The oxidative metabolism of acetic acid bacteria (AAB) can be exploited for the production of several compounds, including D-gluconic acid. The production of D-gluconic acid in fermented beverages could be useful for the development of new products without glucose. In the present study, we analyzed nineteen strains belonging to eight different species of AAB to select those that could produce D-gluconic acid from D-glucose without consuming D-fructose. We tested their performance in three different media and analyzed the changes in the levels of D-glucose, D-fructose, D-gluconic acid and the derived gluconates. D-Glucose and D-fructose consumption and D-gluconic acid production were heavily dependent on the strain and the media. The most suitable strains for our purpose were Gluconobacter japonicus CECT 8443 and Gluconobacter oxydans Po5. The strawberry isolate Acetobacter malorum (CECT 7749) also produced D-gluconic acid; however, it further oxidized D-gluconic acid to keto-D-gluconates. PMID:26848948

  10. [Advances in the progress of anti-bacterial biofilms properties of acetic acid].

    PubMed

    Gao, Xinxin; Jin, Zhenghua; Chen, Xinxin; Yu, Jia'ao

    2016-06-01

    Bacterial biofilms are considered to be the hindrance in the treatment of chronic wound, because of their tolerance toward antibiotics and other antimicrobial agents. They also have strong ability to escape from the host immune attack. Acetic acid, as a kind of organic weak acid, can disturb the biofilms by freely diffusing through the bacterial biofilms and bacterial cell membrane structure. Then the acid dissociates to release the hydrogen ions, leading to the disorder of the acid-base imbalance, change of protein conformation, and the degradation of the DNA within the membranes. This paper reviews the literature on the characteristics and treatment strategies of the bacterial biofilms and the acetic acid intervention on them, so as to demonstrate the roles acetic acid may play in the treatment of chronic wound, and thus provide a convincing treatment strategy for this kind of disease. PMID:27321493

  11. Zinc, magnesium, and calcium ion supplementation confers tolerance to acetic acid stress in industrial Saccharomyces cerevisiae utilizing xylose.

    PubMed

    Ismail, Ku Syahidah Ku; Sakamoto, Takatoshi; Hasunuma, Tomohisa; Zhao, Xin-Qing; Kondo, Akihiko

    2014-12-01

    Lignocellulosic biomass is a potential substrate for ethanol production. However, pretreatment of lignocellulosic materials produces inhibitory compounds such as acetic acid, which negatively affect ethanol production by Saccharomyces cerevisiae. Supplementation of the medium with three metal ions (Zn(2+) , Mg(2+) , and Ca(2+) ) increased the tolerance of S. cerevisiae toward acetic acid compared to the absence of the ions. Ethanol production from xylose was most improved (by 34%) when the medium was supplemented with 2 mM Ca(2+) , followed by supplementation with 3.5 mM Mg(2+) (29% improvement), and 180 μM Zn(2+) (26% improvement). Higher ethanol production was linked to high cell viability in the presence of metal ions. Comparative transcriptomics between the supplemented cultures and the control suggested that improved cell viability resulted from the induction of genes controlling the cell wall and membrane. Only one gene, FIT2, was found to be up-regulated in common between the three metal ions. Also up-regulation of HXT1 and TKL1 might enhance xylose consumption in the presence of acetic acid. Thus, the addition of ionic nutrients is a simple and cost-effective method to improve the acetic acid tolerance of S. cerevisiae. PMID:24924214

  12. Reaction engineering analysis of hydrogenotrophic production of acetic acid by Acetobacterium woodii.

    PubMed

    Demler, Martin; Weuster-Botz, Dirk

    2011-02-01

    Great interest has emerged in biological CO₂-fixing processes in the context of current climate change discussions. One example for such a process is the hydrogenotrophic production of acetic acid by anaerobic microorganisms. Acetogenic microorganisms make use of carbon dioxide in the presence of hydrogen to produce acetic acid and biomass. In order to establish a process for the hydrogenotrophic production of acetic acid, the formation of acetate by Acetobacterium woodii was studied in a batch-operated stirred-tank bioreactor at different hydrogen partial pressures (pH₂) in the gas phase. The volumetric productivity of the batch processes increased with increasing hydrogen partial pressure. A maximum of the volumetric productivity of 7.4 g(acetate) L⁻¹ day⁻¹ was measured at a pH₂ of 1,700 mbar. At this pH(2) a final acetate concentration of 44 g L⁻¹ was measured after a process time of 11 days, if the pH was controlled at pH 7.0 (average cell density of 1.1 g L⁻¹ cell dry weight). The maximum cell specific actetate productivity was 6.9 g(acetate) g(cdw)⁻¹ day⁻¹ under hydrogenotrophic conditions. PMID:20830677

  13. Isolation of acetic, propionic and butyric acid-forming bacteria from biogas plants.

    PubMed

    Cibis, Katharina Gabriela; Gneipel, Armin; König, Helmut

    2016-02-20

    In this study, acetic, propionic and butyric acid-forming bacteria were isolated from thermophilic and mesophilic biogas plants (BGP) located in Germany. The fermenters were fed with maize silage and cattle or swine manure. Furthermore, pressurized laboratory fermenters digesting maize silage were sampled. Enrichment cultures for the isolation of acid-forming bacteria were grown in minimal medium supplemented with one of the following carbon sources: Na(+)-dl-lactate, succinate, ethanol, glycerol, glucose or a mixture of amino acids. These substrates could be converted by the isolates to acetic, propionic or butyric acid. In total, 49 isolates were obtained, which belonged to the phyla Firmicutes, Tenericutes or Thermotogae. According to 16S rRNA gene sequences, most isolates were related to Clostridium sporosphaeroides, Defluviitoga tunisiensis and Dendrosporobacter quercicolus. Acetic, propionic or butyric acid were produced in cultures of isolates affiliated to Bacillus thermoamylovorans, Clostridium aminovalericum, Clostridium cochlearium/Clostridium tetani, C. sporosphaeroides, D. quercicolus, Proteiniborus ethanoligenes, Selenomonas bovis and Tepidanaerobacter sp. Isolates related to Thermoanaerobacterium thermosaccharolyticum produced acetic, butyric and lactic acid, and isolates related to D. tunisiensis formed acetic acid. Specific primer sets targeting 16S rRNA gene sequences were designed and used for real-time quantitative PCR (qPCR). The isolates were physiologically characterized and their role in BGP discussed. PMID:26779817

  14. Growth and survival of various strains of enterohemorrhagic Escherichia coli in hydrochloric and acetic acid.

    PubMed

    McKellar, R C; Knight, K P

    1999-12-01

    Nineteen strains of enterohemorrhagic Escherichia coli isolated from humans and foods were examined for their ability to grow and survive at low pH in organic (acetic) and mineral (HCl) acids. Strains were subcultured in tryptic soy broth adjusted to various pH values (3.75 to 4.75 for HCl and 4.75 to 5.75 for acetic acid) and incubated for 72 h at 37 degrees C to determine the minimum growth pH value. Minimum pH values for growth of 4.25 and 5.5 were found for HCl and acetic acid, respectively. Strains were also exposed to pH 2.0 (HCl) and pH 4.0 (acetic acid) for up to 24 h at 37 degrees C to assess their ability to survive. HCl was a more effective inhibitor after 6 h of exposure, whereas acetic acid was more effective after 24 h. Outbreak strains survived acid treatment significantly (P < or = 0.05) better than strains isolated from fermented or high-pH foods or animal or human isolates. Significant (P < or = 0.05) differences among serotypes and between O157:H7 and other serotypes were apparent after 3 or 6 h of exposure to acids. PMID:10606153

  15. Microwave Spectroscopy and Proton Transfer Dynamics in the Formic Acid-Acetic Acid Dimer

    NASA Astrophysics Data System (ADS)

    Howard, B. J.; Steer, E.; Page, F.; Tayler, M.; Ouyang, B.; Leung, H. O.; Marshall, M. D.; Muenter, J. S.

    2012-06-01

    The rotational spectrum of the doubly hydrogen-bonded {hetero} dimer formed between formic acid and acetic acid has been recorded between 4 and 18 GHz using a pulsed-nozzle Fourier transform microwave spectrometer. Each rigid-molecule rotational transition is split into four as a result of two concurrent tunnelling motions, one being proton transfer between the two acid molecules, and the other the torsion/rotation of the methyl group within the acetic acid. We present a full assignment of the spectrum for {J} = 1 to {J} = 7 for these four torsion/tunnelling states. Spectra have been observed for the main isotopic species, with deuterium substitution at the C of the formic acid and all 13C species in natural abundance, The observed transitions are fitted to within a few kilohertz using a molecule-fixed effective rotational Hamiltonian for the separate {A} and {E} vibrational species of the G12 permutation-inversion group which is applicable to this complex. To reduce the effects of internal angular momentum, a non-principal axis system is used throughout. Interpretation of the internal motion uses an internal-vibration and overall rotation scheme, and full sets of rotational and centrifugal distortion constants are determined. The proton tunnelling rates and the internal angular momentum of the methyl group in the {E} states is interpreted in terms of a dynamical model which involves coupled proton transfer and internal rotation. The resulting potential energy surface not only describes these internal motions, but can also explain the observed shifts in rotational constants between {A} and {E} species, and the deviations of the tunnelling frequencies from the expected 2:1 ratio. It also permits the determination of spectral constants free from the contamination effects of the internal dynamics. M.C.D. Tayler, B. Ouyang and B.J. Howard, J. Chem. Phys., {134}, 054316 (2011).

  16. Improvement of sensitivity of electrolyte cathode discharge atomic emission spectrometry (ELCAD-AES) for mercury using acetic acid medium.

    PubMed

    Shekhar, R

    2012-05-15

    A method has been developed to improve the sensitivity of the electrolyte cathode discharge atomic emission spectrometry (ELCAD-AES) for mercury determination. Effects of various low molecular weight organic solvents at different volume percentages as well as at different acid molarities on the mercury signal were investigated using ELCAD-AES. The addition of few percent of organic solvent, acetic acid produced significant enhancement in mercury signal. Acetic acid of 5% (v/v) with the 0.2M acidity has been found to give 500% enhancement for mercury signal in flow injection mode. Under the optimized parameters the repeatability, expressed as the percentage relative standard deviation of spectral peak area for mercury with 5% acetic acid was found to be 10% for acid blank solution and 5% for 20 ng/mL mercury standard based on multiple measurements with a multiple sample loading in flow injection mode. Limit of detection of this method was determined to be 2 ng/mL for inorganic mercury. The proposed method has been validated by determining mercury in certified reference materials, Tuna fish (IAEA-350) and Aquatic plant (BCR-060). Accuracy of the method for the mercury determination in the reference materials has been found to be between 3.5% and 5.9%. This study enhances the utility of ELCAD-AES for various types of biological and environmental materials to quantify total mercury at very low levels. PMID:22483872

  17. Acetate Salts as Nonhalogen Additives To Improve Perovskite Film Morphology for High-Efficiency Solar Cells.

    PubMed

    Wu, Qiliang; Zhou, Pengcheng; Zhou, Weiran; Wei, Xiangfeng; Chen, Tao; Yang, Shangfeng

    2016-06-22

    A two-step method has been popularly adopted to fabricate a perovskite film of planar heterojunction organo-lead halide perovskite solar cells (PSCs). However, this method often generates uncontrollable film morphology with poor coverage. Herein, we report a facile method to improve perovskite film morphology by incorporating a small amount of acetate (CH3COO(-), Ac(-)) salts (NH4Ac, NaAc) as nonhalogen additives in CH3NH3I solution used for immersing PbI2 film, resulting in improved CH3NH3PbI3 film morphology. Under the optimized NH4Ac additive concentration of 10 wt %, the best power conversion efficiency (PCE) reaches 17.02%, which is enhanced by ∼23.2% relative to that of the pristine device without additive, whereas the NaAc additive does not lead to an efficiency enhancement despite the improvement of the CH3NH3PbI3 film morphology. SEM study reveals that NH4Ac and NaAc additives can both effectively improve perovskite film morphology by increasing the surface coverage via diminishing pinholes. The improvement on CH3NH3PbI3 film morphology is beneficial for increasing the optical absorption of perovskite film and improving the interfacial contact at the perovskite/spiro-OMeTAD interface, leading to the increase of short-circuit current and consequently efficiency enhancement of the PSC device for NH4Ac additive only. PMID:27253082

  18. Experimental and DFT studies of the conversion of ethanol and acetic acid on PtSn-based catalysts.

    PubMed

    Alcala, Rafael; Shabaker, John W; Huber, George W; Sanchez-Castillo, Marco A; Dumesic, James A

    2005-02-17

    Reaction kinetics studies were conducted for the conversions of ethanol and acetic acid over silica-supported Pt and Pt/Sn catalysts at temperatures from 500 to 600 K. Addition of Sn to Pt catalysts inhibits the decomposition of ethanol to CO, CH4, and C2H6, such that PtSn-based catalysts are active for dehydrogenation of ethanol to acetaldehyde. Furthermore, PtSn-based catalysts are selective for the conversion of acetic acid to ethanol, acetaldehyde, and ethyl acetate, whereas Pt catalysts lead mainly to decomposition products such as CH4 and CO. These results are interpreted using density functional theory (DFT) calculations for various adsorbed species and transition states on Pt(111) and Pt3Sn(111) surfaces. The Pt3Sn alloy slab was selected for DFT studies because results from in situ (119)Sn Mössbauer spectroscopy and CO adsorption microcalorimetry of silica-supported Pt/Sn catalysts indicate that Pt-Sn alloy is the major phase present. Accordingly, results from DFT calculations show that transition-state energies for C-O and C-C bond cleavage in ethanol-derived species increase by 25-60 kJ/mol on Pt3Sn(111) compared to Pt(111), whereas energies of transition states for dehydrogenation reactions increase by only 5-10 kJ/mol. Results from DFT calculations show that transition-state energies for CH3CO-OH bond cleavage increase by only 12 kJ/mol on Pt3Sn(111) compared to Pt(111). The suppression of C-C bond cleavage in ethanol and acetic acid upon addition of Sn to Pt is also confirmed by microcalorimetric and infrared spectroscopic measurements at 300 K of the interactions of ethanol and acetic acid with Pt and PtSn on a silica support that had been silylated to remove silanol groups. PMID:16851198

  19. Acetic acid bacteria: A group of bacteria with versatile biotechnological applications.

    PubMed

    Saichana, Natsaran; Matsushita, Kazunobu; Adachi, Osao; Frébort, Ivo; Frebortova, Jitka

    2015-11-01

    Acetic acid bacteria are gram-negative obligate aerobic bacteria assigned to the family Acetobacteraceae of Alphaproteobacteria. They are members of the genera Acetobacter, Gluconobacter, Gluconacetobacter, Acidomonas, Asaia, Kozakia, Swaminathania, Saccharibacter, Neoasaia, Granulibacter, Tanticharoenia, Ameyamaea, Neokomagataea, and Komagataeibacter. Many strains of Acetobacter and Komagataeibacter have been known to possess high acetic acid fermentation ability as well as the acetic acid and ethanol resistance, which are considered to be useful features for industrial production of acetic acid and vinegar, the commercial product. On the other hand, Gluconobacter strains have the ability to perform oxidative fermentation of various sugars, sugar alcohols, and sugar acids leading to the formation of several valuable products. Thermotolerant strains of acetic acid bacteria were isolated in order to serve as the new strains of choice for industrial fermentations, in which the cooling costs for maintaining optimum growth and production temperature in the fermentation vessels could be significantly reduced. Genetic modifications by adaptation and genetic engineering were also applied to improve their properties, such as productivity and heat resistance. PMID:25485864

  20. Laboratory Studies of the Tropospheric Loss Processes for Acetic and Peracetic Acid

    NASA Astrophysics Data System (ADS)

    Orlando, J. J.; Tyndall, G. S.

    2002-12-01

    Organic acids are ubiquitous components of tropospheric air and contribute to acid precipitation, particularly in remote regions. These species are present in the troposphere as the result of direct emissions from anthropogenic and biogenic sources, and as the result of photochemical processing of hydrocarbons. Production of organic acids can occur following ozonolysis of unsaturated hydrocarbons, while both organic acids and peroxyacids are formed from the reactions of HO2 with acylperoxy radicals. For example, both acetic and peracetic acid are known products of the reaction of HO2 with acetylperoxy radicals. In this paper, data relevant to the gas-phase tropospheric destruction of both acetic and peracetic acid are reported, including studies of their UV absorption spectra and of their rate coefficients for reaction with OH radicals. The data, the first of their kind for peracetic acid, show that the gas-phase lifetime of this species will be on the order of 10 days, with OH reaction occurring more rapidly than photolysis. Data on the rate coefficient for reaction of OH with acetic acid appear to resolve some conflicting data in the previous literature, and show 1) that reaction of OH with the acetic acid dimer is slow compared to the monomer and 2) that the rate coefficient possesses a negative temperature dependence near room temperature.

  1. Reactivity and reaction intermediates for acetic acid adsorbed on CeO2(111)

    SciTech Connect

    Calaza, Florencia C.; Chen, Tsung -Liang; Mullins, David R.; Xu, Ye; Steven H. Overbury

    2015-05-02

    Adsorption and reaction of acetic acid on a CeO2(1 1 1) surface was studied by a combination of ultra-highvacuum based methods including temperature desorption spectroscopy (TPD), soft X-ray photoelectronspectroscopy (sXPS), near edge X-ray absorption spectroscopy (NEXAFS) and reflection absorption IRspectroscopy (RAIRS), together with density functional theory (DFT) calculations. TPD shows that thedesorption products are strongly dependent upon the initial oxidation state of the CeO2 surface, includingselectivity between acetone and acetaldehyde products. The combination of sXPS and NEXAFS demon-strate that acetate forms upon adsorption at low temperature and is stable to above 500 K, above whichpoint ketene, acetone and acetic acid desorb. Furthermore, DFT and RAIRS show that below 500 K, bridge bondedacetate coexists with a moiety formed by adsorption of an acetate at an oxygen vacancy, formed bywater desorption.

  2. A laboratory study of the effect of acetic acid vapor on atmospheric copper corrosion

    SciTech Connect

    Lopez-Delgado, A.; Cano, E.; Bastidas, J.M.; Lopez, F.A.

    1998-12-01

    A study was made of the copper corrosion rate and corrosion products originated by the action of acetic acid vapor at 100% relative humidity. Copper plates were exposed to an acetic acid contaminated atmosphere for a period of 21 days. Five acetic vapor concentration levels were used. The copper corrosion rate was in the range of 1 to 23 mg/dm{sup 2} day. The corrosion-product layers were characterized using electrochemical, X-ray powder diffraction, Fourier transform infrared spectrometry, and scanning electron microscopy techniques. Thermal and calorimetric studies were also performed. Some of the compounds identified were cuprite (Cu{sub 2}O), copper acetate hydrate [Cu(CH{sub 3}COO){sub 2}{center_dot}2H{sub 2}O], and copper hydroxide acetate [Cu{sub 4}(OH)(CH{sub 3}COO){sub 7}{center_dot}2H{sub 2}O]. This last compound was also characterized. The thickness of the patina layers was 4 to 8 nm for amorphous cuprite, 11 to 48 nm for cuprite, and 225 nm for copper acetate. The patina, in which the cementation process of different corrosion-product layers plays an important role, is formed by the reaction of acetic vapor with copper through porous cuprite paths.

  3. Structure-activity relationships (SAR) and structure-kinetic relationships (SKR) of pyrrolopiperidinone acetic acids as CRTh2 antagonists.

    PubMed

    Andrés, Miriam; Buil, Maria Antonia; Calbet, Marta; Casado, Oscar; Castro, Jordi; Eastwood, Paul R; Eichhorn, Peter; Ferrer, Manel; Forns, Pilar; Moreno, Imma; Petit, Silvia; Roberts, Richard S

    2014-11-01

    Pyrrolopiperidinone acetic acids (PPAs) were identified as highly potent CRTh2 receptor antagonists. In addition, many of these compounds displayed slow-dissociation kinetics from the receptor. Structure-kinetic relationship (SKR) studies allowed optimisation of the kinetics to give potent analogues with long receptor residence half-lives of up to 23 h. Low permeability was a general feature of this series, however oral bioavailability could be achieved through the use of ester prodrugs. PMID:25437503

  4. Feulgen staining of mammalian tissues fixed in picro-formol-acetic acid.

    PubMed

    Dutt, M K

    1975-01-01

    The paper describes a highly satisfactory method for in situ localization of DNA in tissues fixed in picro-formol-acetic acid or picro-formol-acetic-chromic acid mixtures following a technique in the Feulgen procedure as devised by the author. Mammalian tissues fixed in these fixatives can be hydrolysed in 6N HCl at 35 degrees C for 10 min, rinsed in water, stained with Schiff reagent after exposing the sections under UV light for 10 min, washed in water, dehydrated through a graduated series of ethanol, cleared in xylol and mounted in DPX. Sections of tissues fixed in picro-formol-acetic-chromic acid mixtures after acid hydrolysis when stained with an aqueous solution of basic fuchsin are also found to be very satisfactory for in situ localization of DNA. PMID:55054

  5. Acid Rain Analysis by Standard Addition Titration.

    ERIC Educational Resources Information Center

    Ophardt, Charles E.

    1985-01-01

    The standard addition titration is a precise and rapid method for the determination of the acidity in rain or snow samples. The method requires use of a standard buret, a pH meter, and Gran's plot to determine the equivalence point. Experimental procedures used and typical results obtained are presented. (JN)

  6. Iron chelation using subcutaneous infusions of diethylene triamine penta-acetic acid (DTPA).

    PubMed

    Pippard, M J; Jackson, M J; Hoffman, K; Petrou, M; Modell, C B

    1986-05-01

    The iron chelating ability and potential toxicity of subcutaneous infusions of the calcium and zinc salts of diethylene triamine penta-acetic acid (DTPA) have been assessed in metabolic balance studies in 2 iron-loaded thalassaemic patients. Infusions of calcium DTPA were locally well tolerated and the drug was as effective as desferrioxamine in mobilising iron. However, daily infusions in the 1st patient also produced symptomatic zinc depletion which could not be controlled by simultaneous oral zinc supplements. Zinc DTPA proved ineffective as an iron chelator, but zinc balance could be maintained in the 2nd patient by combining intermittent (every 4 d) use of calcium DTPA with oral zinc supplements. Combined studies with desferrioxamine and calcium DTPA showed the drugs to have additive effects, probably as a result of the chelation of iron from different body sites. PMID:3738427

  7. An in vitro system from maize seedlings for tryptophan-independent indole-3-acetic acid biosynthesis

    SciTech Connect

    Oestin, A.; Ilic, N.; Cohen, J.D.

    1999-01-01

    The enzymatic synthesis of indole-3-acetic acid (IAA) from indole by an in vitro preparation from maize (Zea mays L.) that does not use tryptophan (Trp) as an intermediate is described. Light-grown seedlings of normal maize and the maize mutant orange pericarp were shown to contain the necessary enzymes to convert [{sup 14}C]indole to IAA. The reaction was not inhibited by unlabeled Trp and neither [{sup 14}C]Trp nor [{sup 14}C]serine substituted for [{sup 14}C]indole in this in vitro system. The reaction had a pH optimum greater than 8.0, required a reducing environment, and had an oxidation potential near that of ascorbate. The results obtained with this in vitro enzyme preparation provide strong, additional evidence for the presence of a Trp-independent IAA biosynthesis pathway in plants.

  8. Acetate and other Volatile Fatty Acids - Key Intermediates in marine sediment metabolism - Thermodynamic and kinetic implications

    NASA Astrophysics Data System (ADS)

    Glombitza, C.; Jaussi, M.; Røy, H.; Jørgensen, B. B.

    2014-12-01

    Volatile fatty acids (VFAs) play important roles as key intermediates in the anaerobic metabolism of subsurface microbial communities. Usually they are present in marine sediment pore water in low concentrations as a result of balanced production and consumption, both occurring in the same sediment zone. Thus their low concentrations represent a steady state condition regulated by either thermodynamics or kinetics. We have developed a novel analytical approach for the parallel measurement of several VFAs directly from marine pore water without any sample pretreatment by the use of a 2-dimensional ion chromatography coupled to mass spectrometry. In a first study we analyzed acetate, formate, and propionate in pore water from sediment cores retrieved from 5 different stations within and offshore of the Godhåbsfjord (Greenland). The sediment cores represent different sedimentological conditions, ranging from a typical marine sedimentation site to a glacier/freshwater dominated site. In addition to VFA concentrations, we measured sulfate concentrations, sulfate reduction rates, and cell abundances. We calculated the Gibbs free energy (ΔG) available for sulfate reduction (SR), as well as the VFA turnover times by the in-situ SR rates. The turnover time for acetate by SR ranged from several hours to days in the top cm of sediment and increased to several hundred years at the bottom of the SR zone. From the associated cell abundances we calculated that the VFA turnover times were significantly longer than the diffusion times of the VFA between individual cells. This shows that VFA consumption in the SR zone, and concomitantly the observed pore water concentrations, are not constrained by diffusion. DG values for SR using acetate were >36 kJ/mol which is significantly above the lower limit for anaerobic microbial energy metabolism. It thus remains unclear what controls the VFA concentrations in the sediment.

  9. Density Functional Investigation of the Adsorption of Isooctane, Ethanol, and Acetic Acid on a Water-Covered Fe(100) Surface

    PubMed Central

    2014-01-01

    The presence of water in biofuels poses the question of how it affects the frictional performance of additives in fuels containing organic substances. To investigate the effect of water on the adsorption of molecules present in fuel and its additives we simulated within the framework of density functional theory the adsorption of ethanol, isooctane (2,2,4-trimethylpentane), and acetic acid on a bare and a water-covered Fe(100) surface. Van der Waals interactions are taken into account in our computations. In those molecules, where dispersion forces contribute significantly to the binding mechanism, the water layer has a stronger screening effect. Additionally, this effect can be enhanced by the presence of polar functional groups in the molecule. Thus, with the introduction of a water layer, the adsorption energy of isooctane and ethanol is reduced but it is increased in the case of the acetic acid. The adsorption configuration of ethanol is changed, while the one of acetic acid is moderately, and for isooctane only very slightly altered. Therefore, the effect of a water layer in the adsorption of organic molecules on an Fe(100) surface strongly depends on the type of bond and consequently, so do the tribological properties. PMID:25243045

  10. Candida zemplinina Can Reduce Acetic Acid Produced by Saccharomyces cerevisiae in Sweet Wine Fermentations

    PubMed Central

    Rantsiou, Kalliopi; Dolci, Paola; Giacosa, Simone; Torchio, Fabrizio; Tofalo, Rosanna; Torriani, Sandra; Suzzi, Giovanna; Rolle, Luca

    2012-01-01

    In this study we investigated the possibility of using Candida zemplinina, as a partner of Saccharomyces cerevisiae, in mixed fermentations of must with a high sugar content, in order to reduce its acetic acid production. Thirty-five C. zemplinina strains, which were isolated from different geographic regions, were molecularly characterized, and their fermentation performances were determined. Five genetically different strains were selected for mixed fermentations with S. cerevisiae. Two types of inoculation were carried out: coinoculation and sequential inoculation. A balance between the two species was generally observed for the first 6 days, after which the levels of C. zemplinina started to decrease. Relevant differences were observed concerning the consumption of sugars, the ethanol and glycerol content, and acetic acid production, depending on which strain was used and which type of inoculation was performed. Sequential inoculation led to the reduction of about half of the acetic acid content compared to the pure S. cerevisiae fermentation, but the ethanol and glycerol amounts were also low. A coinoculation with selected combinations of S. cerevisiae and C. zemplinina resulted in a decrease of ∼0.3 g of acetic acid/liter, while maintaining high ethanol and glycerol levels. This study demonstrates that mixed S. cerevisiae and C. zemplinina fermentation could be applied in sweet wine fermentation to reduce the production of acetic acid, connected to the S. cerevisiae osmotic stress response. PMID:22247148

  11. Acetic Acid Detection Threshold in Synthetic Wine Samples of a Portable Electronic Nose

    PubMed Central

    Macías, Miguel Macías; Manso, Antonio García; Orellana, Carlos Javier García; Velasco, Horacio Manuel González; Caballero, Ramón Gallardo; Chamizo, Juan Carlos Peguero

    2013-01-01

    Wine quality is related to its intrinsic visual, taste, or aroma characteristics and is reflected in the price paid for that wine. One of the most important wine faults is the excessive concentration of acetic acid which can cause a wine to take on vinegar aromas and reduce its varietal character. Thereby it is very important for the wine industry to have methods, like electronic noses, for real-time monitoring the excessive concentration of acetic acid in wines. However, aroma characterization of alcoholic beverages with sensor array electronic noses is a difficult challenge due to the masking effect of ethanol. In this work, in order to detect the presence of acetic acid in synthetic wine samples (aqueous ethanol solution at 10% v/v) we use a detection unit which consists of a commercial electronic nose and a HSS32 auto sampler, in combination with a neural network classifier (MLP). To find the characteristic vector representative of the sample that we want to classify, first we select the sensors, and the section of the sensors response curves, where the probability of detecting the presence of acetic acid will be higher, and then we apply Principal Component Analysis (PCA) such that each sensor response curve is represented by the coefficients of its first principal components. Results show that the PEN3 electronic nose is able to detect and discriminate wine samples doped with acetic acid in concentrations equal or greater than 2 g/L. PMID:23262483

  12. The Antibacterial Activity of Acetic Acid against Biofilm-Producing Pathogens of Relevance to Burns Patients

    PubMed Central

    Halstead, Fenella D.; Rauf, Maryam; Moiemen, Naiem S.; Bamford, Amy; Wearn, Christopher M.; Fraise, Adam P.; Lund, Peter A.; Oppenheim, Beryl A.; Webber, Mark A.

    2015-01-01

    Introduction Localised infections, and burn wound sepsis are key concerns in the treatment of burns patients, and prevention of colonisation largely relies on biocides. Acetic acid has been shown to have good antibacterial activity against various planktonic organisms, however data is limited on efficacy, and few studies have been performed on biofilms. Objectives We sought to investigate the antibacterial activity of acetic acid against important burn wound colonising organisms growing planktonically and as biofilms. Methods Laboratory experiments were performed to test the ability of acetic acid to inhibit growth of pathogens, inhibit the formation of biofilms, and eradicate pre-formed biofilms. Results Twenty-nine isolates of common wound-infecting pathogens were tested. Acetic acid was antibacterial against planktonic growth, with an minimum inhibitory concentration of 0.16–0.31% for all isolates, and was also able to prevent formation of biofilms (at 0.31%). Eradication of mature biofilms was observed for all isolates after three hours of exposure. Conclusions This study provides evidence that acetic acid can inhibit growth of key burn wound pathogens when used at very dilute concentrations. Owing to current concerns of the reducing efficacy of systemic antibiotics, this novel biocide application offers great promise as a cheap and effective measure to treat infections in burns patients. PMID:26352256

  13. Asaia bogorensis gen. nov., sp. nov., an unusual acetic acid bacterium in the alpha-Proteobacteria.

    PubMed

    Yamada, Y; Katsura, K; Kawasaki, H; Widyastuti, Y; Saono, S; Seki, T; Uchimura, T; Komagata, K

    2000-03-01

    Eight Gram-negative, aerobic, rod-shaped and peritrichously flagellated strains were isolated from flowers of the orchid tree (Bauhinia purpurea) and of plumbago (Plumbago auriculata), and from fermented glutinous rice, all collected in Indonesia. The enrichment culture approach for acetic acid bacteria was employed, involving use of sorbitol medium at pH 3.5. All isolates grew well at pH 3.0 and 30 degrees C. They did not oxidize ethanol to acetic acid except for one strain that oxidized ethanol weakly, and 0.35% acetic acid inhibited their growth completely. However, they oxidized acetate and lactate to carbon dioxide and water. The isolates grew well on mannitol agar and on glutamate agar, and assimilated ammonium sulfate for growth on vitamin-free glucose medium. The isolates produced acid from D-glucose, D-fructose, L-sorbose, dulcitol and glycerol. The quinone system was Q-10. DNA base composition ranged from 59.3 to 61.0 mol% G + C. Studies of DNA relatedness showed that the isolates constitute a single species. Phylogenetic analysis based on their 16S rRNA gene sequences indicated that the isolates are located in the acetic acid bacteria lineage, but distant from the genera Acetobacter, Gluconobacter, Acidomonas and Gluconacetobacter. On the basis of the above characteristics, the name Asaia bogorensis gen. nov., sp. nov. is proposed for these isolates. The type strain is isolate 71T (= NRIC 0311T = JCM 10569T). PMID:10758893

  14. Potential biofuel additive from renewable sources--Kinetic study of formation of butyl acetate by heterogeneously catalyzed transesterification of ethyl acetate with butanol.

    PubMed

    Ali, Sami H; Al-Rashed, Osama; Azeez, Fadhel A; Merchant, Sabiha Q

    2011-11-01

    Butyl acetate holds great potential as a sustainable biofuel additive. Heterogeneously catalyzed transesterification of biobutanol and bioethylacetate can produce butyl acetate. This route is eco-friendly and offers several advantages over the commonly used Fischer Esterification. The Amberlite IR 120- and Amberlyst 15-catalyzed transesterification is studied in a batch reactor over a range of catalyst loading (6-12 wt.%), alcohol to ester feed ratio (1:3 to 3:1), and temperature (303.15-333.15K). A butanol mole fraction of 0.2 in the feed is found to be optimum. Amberlite IR 120 promotes faster kinetics under these conditions. The transesterifications studied are slightly exothermic. The moles of solvent sorbed per gram of catalyst decreases (ethanol>butanol>ethyl acetate>butyl acetate) with decrease in solubility parameter. The dual site models, the Langmuir Hinshelwood and Popken models, are the most successful in correlating the kinetics over Amberlite IR 120 and Amberlyst 15, respectively. PMID:21908187

  15. Formic and Acetic Acid Observations over Colorado by Chemical Ionization Mass Spectrometry and Organic Acids' Role in Air Quality

    NASA Astrophysics Data System (ADS)

    Treadaway, V.; O'Sullivan, D. W.; Heikes, B.; Silwal, I.; McNeill, A.

    2015-12-01

    Formic acid (HFo) and acetic acid (HAc) have both natural and anthropogenic sources and a role in the atmospheric processing of carbon. These organic acids also have an increasing importance in setting the acidity of rain and snow as precipitation nitrate and sulfate concentrations have decreased. Primary emissions for both organic acids include biomass burning, agriculture, and motor vehicle emissions. Secondary production is also a substantial source for both acids especially from biogenic precursors, secondary organic aerosols (SOAs), and photochemical production from volatile organic compounds (VOCs) and oxygenated volatile organic compounds (OVOCs). Chemical transport models underestimate organic acid concentrations and recent research has sought to develop additional production mechanisms. Here we report HFo and HAc measurements during two campaigns over Colorado using the peroxide chemical ionization mass spectrometer (PCIMS). Iodide clusters of both HFo and HAc were recorded at mass-to-charge ratios of 173 and 187, respectively. The PCIMS was flown aboard the NCAR Gulfstream-V platform during the Deep Convective Clouds and Chemistry Experiment (DC3) and aboard the NCAR C-130 during the Front Range Air Pollution and Photochemistry Experiment (FRAPPE). The DC3 observations were made in May and June 2012 extending from the surface to 13 km over the central and eastern United States. FRAPPE observations were made in July and August 2014 from the surface to 7 km over Colorado. DC3 measurements reported here are focused over the Colorado Front Range and complement the FRAPPE observations. DC3 HFo altitude profiles are characterized by a decrease up to 6 km followed by an increase either back to boundary layer mixing ratio values or higher (a "C" shape). Organic acid measurements from both campaigns are interpreted with an emphasis on emission sources (both natural and anthropogenic) over Colorado and in situ photochemical production especially ozone precursors.

  16. Measuring acetic acid dimer modes by ultrafast time-domain Raman spectroscopy.

    PubMed

    Heisler, Ismael A; Mazur, Kamila; Yamaguchi, Sayuri; Tominaga, Keisuke; Meech, Stephen R

    2011-09-14

    Acetic acid is capable of forming strong multiple hydrogen bonds and therefore different dimeric H-bonded structures in neat liquid phase and in solutions. The low frequency Raman spectra of acetic acid (neat, in aqueous solution and as a function of temperature) were obtained by ultrafast time and polarization resolved optical Kerr effect (OKE) measurements. Isotropic OKE measurements clearly reveal a specific totally symmetric mode related to the dimeric structure H-bond stretching mode. The effects of isotope substitution, water dilution and temperature on this mode were investigated. These results together with anisotropic OKE measurements and density functional theory calculations for a number of possible dimers provide strong evidence for the cyclic dimer structure being the main structure in liquid phase persisting down to acetic acid concentrations of 10 M. Some information about the dimer structure and concentration dependence was inferred. PMID:21625711

  17. Molecular mechanisms of Saccharomyces cerevisiae stress adaptation and programmed cell death in response to acetic acid

    PubMed Central

    Giannattasio, Sergio; Guaragnella, Nicoletta; Ždralević, Maša; Marra, Ersilia

    2013-01-01

    Beyond its classical biotechnological applications such as food and beverage production or as a cell factory, the yeast Saccharomyces cerevisiae is a valuable model organism to study fundamental mechanisms of cell response to stressful environmental changes. Acetic acid is a physiological product of yeast fermentation and it is a well-known food preservative due to its antimicrobial action. Acetic acid has recently been shown to cause yeast cell death and aging. Here we shall focus on the molecular mechanisms of S. cerevisiae stress adaptation and programmed cell death in response to acetic acid. We shall elaborate on the intracellular signaling pathways involved in the cross-talk of pro-survival and pro-death pathways underlying the importance of understanding fundamental aspects of yeast cell homeostasis to improve the performance of a given yeast strain in biotechnological applications. PMID:23430312

  18. Molecular mechanisms of Saccharomyces cerevisiae stress adaptation and programmed cell death in response to acetic acid.

    PubMed

    Giannattasio, Sergio; Guaragnella, Nicoletta; Zdralević, Maša; Marra, Ersilia

    2013-01-01

    Beyond its classical biotechnological applications such as food and beverage production or as a cell factory, the yeast Saccharomyces cerevisiae is a valuable model organism to study fundamental mechanisms of cell response to stressful environmental changes. Acetic acid is a physiological product of yeast fermentation and it is a well-known food preservative due to its antimicrobial action. Acetic acid has recently been shown to cause yeast cell death and aging. Here we shall focus on the molecular mechanisms of S. cerevisiae stress adaptation and programmed cell death in response to acetic acid. We shall elaborate on the intracellular signaling pathways involved in the cross-talk of pro-survival and pro-death pathways underlying the importance of understanding fundamental aspects of yeast cell homeostasis to improve the performance of a given yeast strain in biotechnological applications. PMID:23430312

  19. Tuning the properties of polyhydroxybutyrate films using acetic acid via solvent casting

    NASA Astrophysics Data System (ADS)

    Anbukarasu, Preetam; Sauvageau, Dominic; Elias, Anastasia

    2015-12-01

    Biodegradable polyhydroxybutyrate (PHB) films were fabricated using acetic acid as an alternative to common solvents such as chloroform. The PHB films were prepared using a solvent casting process at temperatures ranging from 80 °C to 160 °C. The crystallinity, mechanical properties and surface morphology of the films cast at different temperatures were characterized and compared to PHB films cast using chloroform as a solvent. Results revealed that the properties of the PHB film varied considerably with solvent casting temperature. In general, samples processed with acetic acid at low temperatures had comparable mechanical properties to PHB cast using chloroform. This acetic acid based method is environmentally friendly, cost efficient and allows more flexible processing conditions and broader ranges of polymer properties than traditional methods.

  20. Effect of acetic acid on physical properties of pregelatinized wheat and corn starch gels.

    PubMed

    Majzoobi, Mahsa; Kaveh, Zahra; Farahnaky, Asgar

    2016-04-01

    Pregelatinized starches are physically modified starches with ability to absorb water and increase viscosity at ambient temperature. The main purpose of this study was to determine how different concentrations of acetic acid (0, 500, 1000, 10,000 mg/kg) can affect functional properties of pregelatinized wheat and corn starches (PGWS and PGCS, respectively) produced by a twin drum drier. With increasing acetic acid following changes occurred for both samples; cold water solubility (at 25 °C) increased, water absorption and apparent cold water viscosity (at 25 °C) reduced, the smooth surface of the starch particles converted to an uneven surface as confirmed by scanning electron microscopy, cohesiveness, consistency and turbidity of the starch gels reduced while their syneresis increased. It was found that in presence of acetic acid, PGWS resulted in higher water absorption and apparent cold water viscosity and produced more cohesive and turbid gels with less syneresis compared to PGCS. PMID:26593546

  1. A Search for Interstellar Acetic Acid Using the BIMA and OVRO Millimeter Arrays

    NASA Astrophysics Data System (ADS)

    Mehringer, D. M.; Snyder, L. E.; Miao, Y.; Lovas, F. J.

    1996-03-01

    We have used the Berkeley-Illinois-Maryland Association (BIMA) and the Caltech Owens Valley (OVRO) millimeter arrays to search for acetic acid (CH_3COOH) in the Sgr B2 Large Molecule Heimat source (e.g., Miao et al. 1995, ApJ, 445, L59). With the BIMA Array, we observed two transitions near 90 GHz. One of these lines is blended with the 37_{8,29} ->37_{8,30} line of methyl formate,(HCOOCH_3) and so an unambiguous identification is difficult. The other line is in a clear spectral region and we have a detection at the 5 sigma level. In order to confirm that this line is due to acetic acid, we have used the OVRO Millimeter Array to search for another pair of acetic acid lines near 100 GHz. These data are currently being reduced, and we will discuss our results.

  2. Tuning the properties of polyhydroxybutyrate films using acetic acid via solvent casting

    PubMed Central

    Anbukarasu, Preetam; Sauvageau, Dominic; Elias, Anastasia

    2015-01-01

    Biodegradable polyhydroxybutyrate (PHB) films were fabricated using acetic acid as an alternative to common solvents such as chloroform. The PHB films were prepared using a solvent casting process at temperatures ranging from 80 °C to 160 °C. The crystallinity, mechanical properties and surface morphology of the films cast at different temperatures were characterized and compared to PHB films cast using chloroform as a solvent. Results revealed that the properties of the PHB film varied considerably with solvent casting temperature. In general, samples processed with acetic acid at low temperatures had comparable mechanical properties to PHB cast using chloroform. This acetic acid based method is environmentally friendly, cost efficient and allows more flexible processing conditions and broader ranges of polymer properties than traditional methods. PMID:26640089

  3. 40 CFR 721.10074 - Acetic acid, 2-chloro-, 1-(3,3-dimethylcyclohexyl)ethyl ester.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Acetic acid, 2-chloro-, 1-(3,3... Specific Chemical Substances § 721.10074 Acetic acid, 2-chloro-, 1-(3,3-dimethylcyclohexyl)ethyl ester. (a... acetic acid, 2-chloro-, 1-(3,3-dimethylcyclohexyl)ethyl ester (PMN P-05-568; CAS No. 477218-59-0)...

  4. 40 CFR 721.10074 - Acetic acid, 2-chloro-, 1-(3,3-dimethylcyclohexyl)ethyl ester.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Acetic acid, 2-chloro-, 1-(3,3... Specific Chemical Substances § 721.10074 Acetic acid, 2-chloro-, 1-(3,3-dimethylcyclohexyl)ethyl ester. (a... acetic acid, 2-chloro-, 1-(3,3-dimethylcyclohexyl)ethyl ester (PMN P-05-568; CAS No. 477218-59-0)...

  5. Bombella intestini gen. nov., sp. nov., an acetic acid bacterium isolated from bumble bee crop.

    PubMed

    Li, Leilei; Praet, Jessy; Borremans, Wim; Nunes, Olga C; Manaia, Célia M; Cleenwerck, Ilse; Meeus, Ivan; Smagghe, Guy; De Vuyst, Luc; Vandamme, Peter

    2015-01-01

    In the frame of a bumble bee gut microbiota study, acetic acid bacteria (AAB) were isolated using a combination of direct isolation methods and enrichment procedures. MALDI-TOF MS profiling of the isolates and a comparison of these profiles with profiles of established AAB species identified most isolates as Asaia astilbis or as 'Commensalibacter intestini', except for two isolates (R-52486 and LMG 28161(T)) that showed an identical profile. A nearly complete 16S rRNA gene sequence of strain LMG 28161(T) was determined and showed the highest pairwise similarity to Saccharibacter floricola S-877(T) (96.5%), which corresponded with genus level divergence in the family Acetobacteraceae. Isolate LMG 28161(T) was subjected to whole-genome shotgun sequencing; a 16S-23S rRNA internal transcribed spacer (ITS) sequence as well as partial sequences of the housekeeping genes dnaK, groEL and rpoB were extracted for phylogenetic analyses. The obtained data confirmed that this isolate is best classified into a new genus in the family Acetobacteraceae. The DNA G+C content of strain LMG 28161(T) was 54.9 mol%. The fatty acid compositions of isolates R-52486 and LMG 28161(T) were similar to those of established AAB species [with C18:1ω7c (43.1%) as the major component], but the amounts of fatty acids such as C19:0 cyclo ω8c, C14:0 and C14:0 2-OH enabled to differentiate them. The major ubiquinone was Q-10. Both isolates could also be differentiated from the known genera of AAB by means of biochemical characteristics, such as their inability to oxidize ethanol to acetic acid, negligible acid production from melibiose, and notable acid production from d-fructose, sucrose and d-mannitol. In addition, they produced 2-keto-d-gluconate, but not 5-keto-d-gluconate from d-glucose. Therefore, the name Bombella intestini gen nov., sp. nov. is proposed for this new taxon, with LMG 28161(T) ( =DSM 28636(T) =R-52487(T)) as the type strain of the type species. PMID:25336723

  6. Use of pooled sodium acetate acetic acid formalin-preserved fecal specimens for the detection of intestinal parasites.

    PubMed

    Gaafar, Maha R

    2011-01-01

    This study aimed at comparing detection of intestinal parasites from single unpreserved stool sample vs. sodium acetate acetic acid formalin (SAF)-preserved pooled samples, and stained with chlorazol black dye in routine practice. Unpreserved samples were collected from 120 patients and represented as Group I. Other three SAF-preserved samples were collected from the same patients over a 6-day period and represented as Groups IIa, IIb, and IIc. The latter groups were equally subdivided into two subgroups. The first subgroup of each of the three samples was examined individually, whereas the second subgroup of each were pooled and examined as a single specimen. All groups were examined by the routine diagnostic techniques; however, in group II when the diagnosis was uncertain, the chlorazol black dye staining procedure was carried out. Results demonstrated that out of 74 patients who continued the study, 12 cases (16%) were positive in group I, compared with 29 (39%) in the subgroups examined individually, and 27 (36%) in the pooled subgroups. Therefore, pooling of preserved fecal samples is an efficient and economical procedure for the detection of parasites. Furthermore, the chlorazol black dye was simple and effective in detecting the nuclear details of different parasites. PMID:21567472

  7. Acetic Acid Can Catalyze Succinimide Formation from Aspartic Acid Residues by a Concerted Bond Reorganization Mechanism: A Computational Study

    PubMed Central

    Takahashi, Ohgi; Kirikoshi, Ryota; Manabe, Noriyoshi

    2015-01-01

    Succinimide formation from aspartic acid (Asp) residues is a concern in the formulation of protein drugs. Based on density functional theory calculations using Ace-Asp-Nme (Ace = acetyl, Nme = NHMe) as a model compound, we propose the possibility that acetic acid (AA), which is often used in protein drug formulation for mildly acidic buffer solutions, catalyzes the succinimide formation from Asp residues by acting as a proton-transfer mediator. The proposed mechanism comprises two steps: cyclization (intramolecular addition) to form a gem-diol tetrahedral intermediate and dehydration of the intermediate. Both steps are catalyzed by an AA molecule, and the first step was predicted to be rate-determining. The cyclization results from a bond formation between the amide nitrogen on the C-terminal side and the side-chain carboxyl carbon, which is part of an extensive bond reorganization (formation and breaking of single bonds and the interchange of single and double bonds) occurring concertedly in a cyclic structure formed by the amide NH bond, the AA molecule and the side-chain C=O group and involving a double proton transfer. The second step also involves an AA-mediated bond reorganization. Carboxylic acids other than AA are also expected to catalyze the succinimide formation by a similar mechanism. PMID:25588215

  8. Combined application of origanum vulgare l. essential oil and acetic acid for controlling the growth of staphylococcus aureus in foods

    PubMed Central

    de Souza, Evandro Leite; de Barros, Jefferson Carneiro; da Conceição, Maria Lúcia; Neto, Nelson Justino Gomes; da Costa, Ana Caroliny Vieira

    2009-01-01

    This study evaluated the occurrence of an enhancing inhibitory effect of the combined application of Origanum vulgare L. essential oil and acetic acid against Staphylococcus aureus by the determination of Fractional Inhibitory Concentration (FIC) index and kill-time assay in nutrient broth, meat broth and in a food model (meat pieces). Acetic acid showed MIC and MFC of 0.6 and 1.25 μL.mL-1, respectively. For O. vulgare essential oil MIC and MBC were 1.25 and 2.5 μL.mL-1, respectively. FIC indexes of the mixture of essential oil and acetic acid at MIC x ½ were ≤ 1.0, showing an additive effect. No synergy was found at kill-time study. Anti-staphylococcal effect of the antimicrobials alone or in mixture (MIC x ½) was lower in meat than in nutrient and meat broths. The effective combination of essential oils and organic acids could appear as an attractive alternative for the food industry, as the doses to inhibit the microbial growth in foods can be lowered. PMID:24031377

  9. [Comparative genomics and evolutionary analysis of CRISPR loci in acetic acid bacteria].

    PubMed

    Kai, Xia; Xinle, Liang; Yudong, Li

    2015-12-01

    The clustered regularly interspaced short palindromic repeat (CRISPR) is a widespread adaptive immunity system that exists in most archaea and many bacteria against foreign DNA, such as phages, viruses and plasmids. In general, CRISPR system consists of direct repeat, leader, spacer and CRISPR-associated sequences. Acetic acid bacteria (AAB) play an important role in industrial fermentation of vinegar and bioelectrochemistry. To investigate the polymorphism and evolution pattern of CRISPR loci in acetic acid bacteria, bioinformatic analyses were performed on 48 species from three main genera (Acetobacter, Gluconacetobacter and Gluconobacter) with whole genome sequences available from the NCBI database. The results showed that the CRISPR system existed in 32 species of the 48 strains studied. Most of the CRISPR-Cas system in AAB belonged to type I CRISPR-Cas system (subtype E and C), but type II CRISPR-Cas system which contain cas9 gene was only found in the genus Acetobacter and Gluconacetobacter. The repeat sequences of some CRISPR were highly conserved among species from different genera, and the leader sequences of some CRISPR possessed conservative motif, which was associated with regulated promoters. Moreover, phylogenetic analysis of cas1 demonstrated that they were suitable for classification of species. The conservation of cas1 genes was associated with that of repeat sequences among different strains, suggesting they were subjected to similar functional constraints. Moreover, the number of spacer was positively correlated with the number of prophages and insertion sequences, indicating the acetic acid bacteria were continually invaded by new foreign DNA. The comparative analysis of CRISR loci in acetic acid bacteria provided the basis for investigating the molecular mechanism of different acetic acid tolerance and genome stability in acetic acid bacteria. PMID:26704949

  10. (+/-)-1-Tetralone-3-carboxylic acid and (+/-)-1-tetralone-2-acetic acid: hydrogen bonding in two gamma-keto acids.

    PubMed

    Barcon, A; Brunskill, A P; Lalancette, R A; Thompson, H W; Miller, A J

    2001-03-01

    The crystal structure of (+/-)-4-oxo-1,2,3,4-tetrahydronaphthalene-2-carboxylic acid (C(11)H(10)O(3)) involves projection of the carboxyl group nearly orthogonal to the aromatic plane and hydrogen bonding of the acid groups by centrosymmetric pairing across the a edge and the center of the chosen cell [O...O = 2.705 (2) A]. Intermolecular C--H...O==C close contacts to translationally related molecules are found for both the ketone (2.55 A) and the acid (2.67 A). In (+/-)-1-oxo-1,2,3,4-tetrahydronaphthalene-2-acetic acid (C(12)H(12)O(3)), the aggregation involves centrosymmetric carboxyl dimers mutually hydrogen bonded across the bc face and the a edge of the chosen cell [O...O = 2.674 (2) A]. A 2.60 A close C--H...O==C contact is found to the carboxyl group of centrosymmetrically related molecule. PMID:11250596

  11. Comparative Indole-3-Acetic Acid Levels in the Slender Pea and Other Pea Phenotypes 1

    PubMed Central

    Law, David M.; Davies, Peter J.

    1990-01-01

    Free indole-3-acetic acid levels were measured by gas chromatography-mass spectrometry in three ultra-tall `slender' Pisum sativum L. lines differing in gibberellin content. Measurements were made for apices and stem elongation zones of light-grown plants and values were compared with wild-type, dwarf, and nana phenotypes in which internode length is genetically regulated, purportedly via the gibberellin level. Indole-3-acetic acid levels of growing stems paralleled growth rates in all lines, and were high in all three slender genotypes. Growth was inhibited by p-chlorophenoxyisobutyric acid, demonstrating the requirement of auxin activity for stem elongation, and also by the ethylene precursor 1-aminocyclopropane-1-carboxylic acid. It is concluded that the slender phenotype may arise from constant activation of a gibberellin receptor or transduction chain event leading directly or indirectly to elevated levels of indole-3-acetic acid, and that increased indole-3-acetic acid levels are a significant factor in the promotion of stem elongation. PMID:16667653

  12. Isolation and characterization of esters of indole-3-acetic acid from the liquid endosperm of the horse chestnut (Aesculus species)

    NASA Technical Reports Server (NTRS)

    Domagalski, W.; Schulze, A.; Bandurski, R. S.

    1987-01-01

    Esters of indole-3-acetic acid were extracted and purified from the liquid endosperm of immature fruits of various species of the horse chestnut (Aesculus parviflora, A. baumanni, A. pavia rubra, and A. pavia humulis). The liquid endosperm contained, at least 12 chromatographically distinct esters. One of these compounds was purified and characterized as an ester of indole-3-acetic acid and myo-inositol. A second compound was found to be an ester of indole-3-acetic acid and the disaccharide rutinose (glucosyl-rhamnose). A third compound was partially characterized as an ester of indole-3-acetic acid and a desoxyaminohexose.

  13. (S) 2-phenyl-2-(p-tolylsulfonylamino)acetic acid. Structure, acidity and its alkali carboxylates

    NASA Astrophysics Data System (ADS)

    Duarte-Hernández, Angélica M.; Contreras, Rosalinda; Suárez-Moreno, Galdina V.; Montes-Tolentino, Pedro; Ramos-García, Iris; González, Felipe J.; Flores-Parra, Angelina

    2015-03-01

    The structure and the preferred conformers of (S) 2-phenyl-2-(p-tolylsulfonylamino)acetic acid (1) are reported. Compound 1 is a derivative of the unnatural aminoacid the (S) phenyl glycine. The X-ray diffraction analyses of the complexes of 1 with water, methanol, pyridine and its own anion are discussed. In order to add information about the acidity of the COOH and NH protons in compound 1, its pKa in DMSO and those of N-benzyl-p-tolylsulfonamide and (S) N-methylbenzyl-p-tolylsulfonamide were determined by cyclic voltammetry. Data improved the scarce information about pKa in DMSO values of sulfonamides. The products of the reactions of compound 1 with one and two equivalents of LiOH, NaOH and KOH in methanol were analyzed. Crystals of the lithium (2) and sodium (3) carboxylates and the dipotassium sulfonylamide acetate (7) were obtained, they are coordination polymers. In compound 2, the lithium is bound to four oxygen atoms with short bond lengths. The coordination of the lithium atom to two carboxylates gives an infinite ribbon by formation of fused six membered rings. In the crystal of compound 3, two pentacoordinated sodium atoms are bridged by three oxygen atoms, one from a water molecule and two from DMSO. The short distance between the sodium atoms (3.123 Å), implies a metal-metal interaction. The sodium couples are linked by two carboxylate groups, forming a planar ribbon of fused twelve membered rings. A notable discovery was a water molecule quenched in the middle of the ring, with a tetra coordinated oxygen atom in a square planar geometry. In compound 7, the carboxylate and the amide are bound to heptacoordinated potassium atoms. The 2D polymer of 7 has a sandwich structure, with the carboxylate and potassium atoms in the inner layer covered by the aromatic rings.

  14. Reactivity and reaction intermediates for acetic acid adsorbed on CeO2(111)

    DOE PAGESBeta

    Calaza, Florencia C.; Chen, Tsung -Liang; Mullins, David R.; Xu, Ye; Steven H. Overbury

    2015-05-02

    Adsorption and reaction of acetic acid on a CeO2(1 1 1) surface was studied by a combination of ultra-highvacuum based methods including temperature desorption spectroscopy (TPD), soft X-ray photoelectronspectroscopy (sXPS), near edge X-ray absorption spectroscopy (NEXAFS) and reflection absorption IRspectroscopy (RAIRS), together with density functional theory (DFT) calculations. TPD shows that thedesorption products are strongly dependent upon the initial oxidation state of the CeO2 surface, includingselectivity between acetone and acetaldehyde products. The combination of sXPS and NEXAFS demon-strate that acetate forms upon adsorption at low temperature and is stable to above 500 K, above whichpoint ketene, acetone and acetic acidmore » desorb. Furthermore, DFT and RAIRS show that below 500 K, bridge bondedacetate coexists with a moiety formed by adsorption of an acetate at an oxygen vacancy, formed bywater desorption.« less

  15. Evolution of Acetic Acid Bacteria During Fermentation and Storage of Wine

    PubMed Central

    Joyeux, A.; Lafon-Lafourcade, S.; Ribéreau-Gayon, P.

    1984-01-01

    Acetic acid bacteria were present at all stages of wine making, from the mature grape through vinification to conservation. A succession of Gluconobacter oxydans, Acetobacter pasteurianus, and Acetobacter aceti during the course of these stages was noted. Low levels of A. aceti remained in the wine; they exhibited rapid proliferation on short exposure of the wine to air and caused significant increases in the concentration of acetic acid. Higher temperature of wine storage and higher wine pH favored the development and metabolism of these species. PMID:16346581

  16. Acetic Acid Bacteria and the Production and Quality of Wine Vinegar

    PubMed Central

    Torija, María Jesús; García-Parrilla, María del Carmen; Troncoso, Ana María

    2014-01-01

    The production of vinegar depends on an oxidation process that is mainly performed by acetic acid bacteria. Despite the different methods of vinegar production (more or less designated as either “fast” or “traditional”), the use of pure starter cultures remains far from being a reality. Uncontrolled mixed cultures are normally used, but this review proposes the use of controlled mixed cultures. The acetic acid bacteria species determine the quality of vinegar, although the final quality is a combined result of technological process, wood contact, and aging. This discussion centers on wine vinegar and evaluates the effects of these different processes on its chemical and sensory properties. PMID:24574887

  17. Activated acetic acid by carbon fixation on (Fe,Ni)S under primordial conditions.

    PubMed

    Huber, C; Wächtershäuser, G

    1997-04-11

    In experiments modeling the reactions of the reductive acetyl-coenzyme A pathway at hydrothermal temperatures, it was found that an aqueous slurry of coprecipitated NiS and FeS converted CO and CH3SH into the activated thioester CH3-CO-SCH3, which hydrolyzed to acetic acid. In the presence of aniline, acetanilide was formed. When NiS-FeS was modified with catalytic amounts of selenium, acetic acid and CH3SH were formed from CO and H2S alone. The reaction can be considered as the primordial initiation reaction for a chemoautotrophic origin of life. PMID:9092471

  18. Spectroscopic and Computational Study of Acetic Acid and Its Cyclic Dimer in the Near-Infrared Region.

    PubMed

    Beć, Krzysztof B; Futami, Yoshisuke; Wójcik, Marek J; Nakajima, Takahito; Ozaki, Yukihiro

    2016-08-11

    Anharmonic vibrational analysis of near-infrared (NIR) spectra of acetic acid was carried out by anharmonic quantum chemical calculation in a wide concentration range of its CCl4 solution. By predicting vibrational spectra of acetic acid for the first time over a wide NIR region, it was possible to elucidate the influence of the formation of acetic acid cyclic dimer on its NIR spectrum. Quantum chemical simulations were based on coupled cluster and density functional theory quantum methods. Additionally, Møller-Plesset perturbation theory was employed for the additional calculation of hydrogen bonding stabilization energies. An anharmonic vibrational analysis was performed with the use of generalized second-order vibrational perturbation theory (GVPT2). A hybrid approach was assumed, in which monomeric species was treated by CCSD(T)/aug-cc-pVDZ (harmonic approximation) and B3LYP/SNSD (anharmonic approximation) methods. For the cyclic dimer, B3LYP and B2PLYP single and double hybrid functionals, paired with an SNSD basis set, were employed. DFT calculations were augmented with additional empirical dispersion correction. It was found that quantum chemically calculated vibrational modes in the NIR region are in a good agreement with experimental data. The results of anharmonic vibrational analysis were supported by a harmonic shift analysis, for elucidating the very strong anharmonic coupling observed between stretching modes of hydrogen bonded bridge in the cyclic dimer. However, the calculated wavenumbers for combination modes of double hydrogen bonded bridge in the cyclic dimer, which are very sensitive to the formation of hydrogen bonding, were found to be underestimated by quantum chemical methods. Therefore, by band fitting, the wavenumbers and shape parameters for these bands were found, and the modeled spectra were adjusted accordingly. A high accuracy of simulated spectra was achieved, and a detailed analysis of the experimental NIR spectra of acetic acid

  19. Sol-gel process for preparing YBa{sub 2}Cu{sub 4}O{sub 8} precursors from Y, Ba, and Cu acidic acetates/ammonia/ascorbic acid systems

    SciTech Connect

    Deptula, A.; Lada, W.; Olczak, T.; Goretta, K.C.; Di Bartolomeo, A.; Casadio, S.

    1995-08-01

    Sols were prepared by addition of ammonia to acidic acetate solutions of Y{sup 3+}, Ba{sup 2+}, and Cu{sup 2+}. Ascorbic acid was added to a part of the sol. The resultant sols were gelled to a shard, a film, or microspheres by evaporation at 60 C or by extraction of water from drops of emulsion suspended in 2-ethylhexanol-1. Addition of ethanol to the sols facilitated the formation of gel films, fabricated by a dipping technique, on glass or silver substrates. At 100 C, gels that were formed in the presence of ascorbic acid were perfectly amorphous, in contrast to the crystalline acetate gels. Conversion of the amorphous ascorbate gels to final products was easier than for the acetate gels. The quality of coatings prepared from ascorbate gels was superior to that of acetate gel coatings.

  20. Culture strategies for lipid production using acetic acid as sole carbon source by Rhodosporidium toruloides.

    PubMed

    Huang, Xiang-Feng; Liu, Jia-Nan; Lu, Li-Jun; Peng, Kai-Ming; Yang, Gao-Xiang; Liu, Jia

    2016-04-01

    Rhodosporidium toruloides AS 2.1389 was tested using different concentrations of acetic acid as a low-cost carbon source for the production of microbial lipids, which are good raw materials for biodiesel production. It grew and had higher lipid contents in media containing 4-20g/L acetic acid as the sole carbon source, compared with that in glucose-containing media under the same culture conditions. At acetic acid concentrations as high as 20g/L and the optimal carbon-to-nitrogen ratio (C/N) of 200 in a batch culture, the highest biomass production was 4.35g/L, with a lipid content of 48.2%. At acetic acid concentrations as low as 4g/L, a sequencing batch culture (SBC) with a C/N of 100 increased biomass production to 4.21g/L, with a lipid content of 38.6%. These results provide usable culture strategies for lipid production by R. toruloides AS 2.1389 when using diverse waste-derived volatile fatty acids. PMID:26851898

  1. Formic and acetic acid over the central Amazon region, Brazil 1. Dry season

    SciTech Connect

    Andreae, M.O.; Talbot, R.W.; Andreae, T.W.; Harriss, R.C.

    1988-02-20

    We have determined the atmospheric concentrations of formic and acetic acid in the gas phase, in aerosols, and in rain during the dry season (July--August 1985) in the Amazonia region of Brazil. At ground level the average concentrations of gas phase formic and acetic acid were 1.6 +- 0.6 and 2.2 +- 1.0 ppb, respectively. The diurnal behavior of both acids at ground level and their vertical distribution in the forest canopy point to the existence of vegetative sources as well as to production by chemical reactions in the atmosphere. Dry deposition of the gaseous acids appears to be a major sink. The concentrations of formic and acetic acid in the gas phase were about 2 orders of magnitude higher than concentrations of the corresponding species in the atmospheric aerosol. About 50--60%/sub 0/ of the aerosol (total) formate and acetate were in the size fraction below 1.0 ..mu..m diameter.

  2. Effect of acetic acid feeding on the circadian changes in glycogen and metabolites of glucose and lipid in liver and skeletal muscle of rats.

    PubMed

    Fushimi, Takashi; Sato, Yuzo

    2005-11-01

    The aim of the present study is to investigate the effect of acetic acid feeding on the circadian changes in glycogen concentration in liver and skeletal muscle. Rats were provided meal once daily (09.00-13.00 hours) for 10 d. On the 11th day, they were either killed immediately or given 9 g diet containing either 0 (control) or 0.7 g/kg-diet acetic acid beginning at 09.00 hours for 4 h, as in the previous regimen. Rats in the fed group were killed at 4, 8 or 24 h after the start of feeding. At 4 h after the start of feeding, the acetic acid group had significantly greater liver and gastrocnemius muscle glycogen concentrations (P<0.05). Also, at this same point, liver xylulose-5-phosphate, a key stimulator of glycolysis, the ratio of fructose-1,6-bisphosphate to fructose-6-phosphate in skeletal muscle, which reflects phosphofructokinase-1 activity, and liver malonyl-CoA, an allosteric inhibitor of carnitine palmitoyl-transferase, were significantly lower in the acetic acid group than in the control group (P<0.05). In addition, the acetic acid group had a significantly lower serum lactate concentration and lower ratio of insulin to glucagon than the control group at the same point (P<0.05). We conclude that a diet containing acetic acid may enhance glycogen repletion but not induce supercompensation, a large increase in the glycogen level that is beneficial in improving performance, in liver and skeletal muscle by transitory inhibition of glycolysis. Further, we indicate the possibility of a transient enhancement of fatty acid oxidation in liver by acetic acid feeding. PMID:16277773

  3. Activation of AMP-Activated Protein Kinase and Stimulation of Energy Metabolism by Acetic Acid in L6 Myotube Cells.

    PubMed

    Maruta, Hitomi; Yoshimura, Yukihiro; Araki, Aya; Kimoto, Masumi; Takahashi, Yoshitaka; Yamashita, Hiromi

    2016-01-01

    Previously, we found that orally administered acetic acid decreased lipogenesis in the liver and suppressed lipid accumulation in adipose tissue of Otsuka Long-Evans Tokushima Fatty rats, which exhibit hyperglycemic obesity with hyperinsulinemia and insulin resistance. Administered acetic acid led to increased phosphorylation of AMP-activated protein kinase (AMPK) in both liver and skeletal muscle cells, and increased transcripts of myoglobin and glucose transporter 4 (GLUT4) genes in skeletal muscle of the rats. It was suggested that acetic acid improved the lipid metabolism in skeletal muscles. In this study, we examined the activation of AMPK and the stimulation of GLUT4 and myoglobin expression by acetic acid in skeletal muscle cells to clarify the physiological function of acetic acid in skeletal muscle cells. Acetic acid added to culture medium was taken up rapidly by L6 cells, and AMPK was phosphorylated upon treatment with acetic acid. We observed increased gene and protein expression of GLUT4 and myoglobin. Uptake of glucose and fatty acids by L6 cells were increased, while triglyceride accumulation was lower in treated cells compared to untreated cells. Furthermore, treated cells also showed increased gene and protein expression of myocyte enhancer factor 2A (MEF2A), which is a well-known transcription factor involved in the expression of myoglobin and GLUT4 genes. These results indicate that acetic acid enhances glucose uptake and fatty acid metabolism through the activation of AMPK, and increases expression of GLUT4 and myoglobin. PMID:27348124

  4. Activation of AMP-Activated Protein Kinase and Stimulation of Energy Metabolism by Acetic Acid in L6 Myotube Cells

    PubMed Central

    Maruta, Hitomi; Yoshimura, Yukihiro; Araki, Aya; Kimoto, Masumi; Takahashi, Yoshitaka; Yamashita, Hiromi

    2016-01-01

    Previously, we found that orally administered acetic acid decreased lipogenesis in the liver and suppressed lipid accumulation in adipose tissue of Otsuka Long-Evans Tokushima Fatty rats, which exhibit hyperglycemic obesity with hyperinsulinemia and insulin resistance. Administered acetic acid led to increased phosphorylation of AMP-activated protein kinase (AMPK) in both liver and skeletal muscle cells, and increased transcripts of myoglobin and glucose transporter 4 (GLUT4) genes in skeletal muscle of the rats. It was suggested that acetic acid improved the lipid metabolism in skeletal muscles. In this study, we examined the activation of AMPK and the stimulation of GLUT4 and myoglobin expression by acetic acid in skeletal muscle cells to clarify the physiological function of acetic acid in skeletal muscle cells. Acetic acid added to culture medium was taken up rapidly by L6 cells, and AMPK was phosphorylated upon treatment with acetic acid. We observed increased gene and protein expression of GLUT4 and myoglobin. Uptake of glucose and fatty acids by L6 cells were increased, while triglyceride accumulation was lower in treated cells compared to untreated cells. Furthermore, treated cells also showed increased gene and protein expression of myocyte enhancer factor 2A (MEF2A), which is a well-known transcription factor involved in the expression of myoglobin and GLUT4 genes. These results indicate that acetic acid enhances glucose uptake and fatty acid metabolism through the activation of AMPK, and increases expression of GLUT4 and myoglobin. PMID:27348124

  5. 2-(Biphenyl-4-yl)acetic acid (felbinac).

    PubMed

    Van Eerdenbrugh, Bernard; Fanwick, Phillip E; Taylor, Lynne S

    2010-01-01

    The structure of the title compound, C(14)H(12)O(2), displays the expected inter-molecular hydrogen bonding of the carb-oxy-lic acid groups, forming dimers. The dihedral angle between the two aromatic rings is 27.01 (7)°. PMID:21587585

  6. 2-(Biphenyl-4-yl)acetic acid (felbinac)

    PubMed Central

    Van Eerdenbrugh, Bernard; Fanwick, Phillip E.; Taylor, Lynne S.

    2010-01-01

    The structure of the title compound, C14H12O2, displays the expected inter­molecular hydrogen bonding of the carb­oxy­lic acid groups, forming dimers. The dihedral angle between the two aromatic rings is 27.01 (7)°. PMID:21587585

  7. Stability of the Acetic Acid-Induced Bladder Irritation Model in Alpha Chloralose-Anesthetized Female Cats

    PubMed Central

    Kullmann, F. Aura; Wells, Grace I.; Langdale, Christopher L.; Zheng, Jihong; Thor, Karl B.

    2013-01-01

    Time- and vehicle-related variability of bladder and urethral rhabdosphincter (URS) activity as well as cardiorespiratory and blood chemistry values were examined in the acetic acid-induced bladder irritation model in α-chloralose-anesthetized female cats. Additionally, bladder and urethra were evaluated histologically using Mason trichrome and toluidine blue staining. Urodynamic, cardiovascular and respiratory parameters were collected during intravesical saline infusion followed by acetic acid (0.5%) to irritate the bladder. One hour after starting acetic acid infusion, a protocol consisting of a cystometrogram, continuous infusion-induced rhythmic voiding contractions, and a 5 min “quiet period” (bladder emptied without infusion) was precisely repeated every 30 minutes. Administration of vehicle (saline i.v.) occurred 15 minutes after starting each of the first 7 cystometrograms and duloxetine (1mg/kg i.v.) after the 8th. Acetic acid infusion into the bladder increased URS-EMG activity, bladder contraction frequency, and decreased contraction amplitude and capacity, compared to saline. Bladder activity and URS activity stabilized within 1 and 2 hours, respectively. Duloxetine administration significantly decreased bladder contraction frequency and increased URS-EMG activity to levels similar to previous reports. Cardiorespiratory parameters and blood gas levels remained consistent throughout the experiment. The epithelium of the bladder and urethra were greatly damaged and edema and infiltration of neutrophils in the lamina propria of urethra were observed. These data provide an ample evaluation of the health of the animals, stability of voiding function and appropriateness of the model for testing drugs designed to evaluate lower urinary tract as well as cardiovascular and respiratory systems function. PMID:24040064

  8. Stability of the acetic acid-induced bladder irritation model in alpha chloralose-anesthetized female cats.

    PubMed

    Kullmann, F Aura; Wells, Grace I; Langdale, Christopher L; Zheng, Jihong; Thor, Karl B

    2013-01-01

    Time- and vehicle-related variability of bladder and urethral rhabdosphincter (URS) activity as well as cardiorespiratory and blood chemistry values were examined in the acetic acid-induced bladder irritation model in α-chloralose-anesthetized female cats. Additionally, bladder and urethra were evaluated histologically using Mason trichrome and toluidine blue staining. Urodynamic, cardiovascular and respiratory parameters were collected during intravesical saline infusion followed by acetic acid (0.5%) to irritate the bladder. One hour after starting acetic acid infusion, a protocol consisting of a cystometrogram, continuous infusion-induced rhythmic voiding contractions, and a 5 min "quiet period" (bladder emptied without infusion) was precisely repeated every 30 minutes. Administration of vehicle (saline i.v.) occurred 15 minutes after starting each of the first 7 cystometrograms and duloxetine (1mg/kg i.v.) after the 8(th). Acetic acid infusion into the bladder increased URS-EMG activity, bladder contraction frequency, and decreased contraction amplitude and capacity, compared to saline. Bladder activity and URS activity stabilized within 1 and 2 hours, respectively. Duloxetine administration significantly decreased bladder contraction frequency and increased URS-EMG activity to levels similar to previous reports. Cardiorespiratory parameters and blood gas levels remained consistent throughout the experiment. The epithelium of the bladder and urethra were greatly damaged and edema and infiltration of neutrophils in the lamina propria of urethra were observed. These data provide an ample evaluation of the health of the animals, stability of voiding function and appropriateness of the model for testing drugs designed to evaluate lower urinary tract as well as cardiovascular and respiratory systems function. PMID:24040064

  9. Calibration and intercomparison of acetic acid measurements using proton transfer reaction mass spectrometry (PTR-MS)

    USGS Publications Warehouse

    Haase, K.B.; Keene, W.C.; Pszenny, A.A.P.; Mayne, H.R.; Talbot, R.W.; Sive, B.C.

    2012-01-01

    Acetic acid is one of the most abundant organic acids in the ambient atmosphere, with maximum mixing ratios reaching into the tens of parts per billion by volume (ppbv) range. The identities and associated magnitudes of the major sources and sinks for acetic acid are poorly characterized, due in part to the limitation in available measurement techniques. This paper demonstrates that Proton Transfer Reaction Mass Spectrometry (PTR-MS) can reliably quantify acetic acid vapor in ambient air. Three different PTR-MS configurations were calibrated at low ppbv mixing ratios using permeation tubes, which yielded calibration factors between 7.0 and 10.9 normalized counts per second per ppbv (ncps ppbv−1) at a drift tube field strength of 132 townsend (Td). Detection limits ranged from 0.06 to 0.32 ppbv with dwell times of 5 s. These calibration factors showed negligible humidity dependence. Using the experimentally determined calibration factors, PTR-MS measurements of acetic acid during the International Consortium for Atmospheric Research on Transport and Transformation (ICARTT) campaign were validated against results obtained using Mist Chambers coupled with Ion Chromatography (MC/IC). An orthogonal least squares linear regression of paired data yielded a slope of 1.14 ± 0.06 (2σ), an intercept of 0.049 ± 20 (2σ) ppbv, and an R2 of 0.78. The median mixing ratio of acetic acid on Appledore Island, ME during the ICARTT campaign was 0.530 ± 0.025 ppbv with a minimum of 0.075 ± 0.004 ppbv, and a maximum of 3.555 ± 0.171 ppbv.

  10. [Concentrations and acidity contributions of acetate and formate in precipitation at 14 stations of China].

    PubMed

    He, Xiao-huan; Xu, Xiao-bin; Yu, Xiao-lan; Tang, Jie

    2010-04-01

    To investigate the concentrations of organic acids in precipitation in China and their contributions to the total acidity of precipitation, samples were taken at 14 stations of regional representativeness in 2007 and analyzed for acetate and formate using ion chromatography. In this paper, data of acetate and formate in precipitation at 14 stations are presented, wet depositions of these organic acids are calculated, and contributions of them to the total free acidity (TFA) of precipitation are estimated. Based on the measurements, the mean concentrations of formate at different stations were in the range of 0.96-3.43 micromol/L, and those of acetate in the range of 0-5.13 micromol/L, close to the levels at remote sites in other countries and at the lower ends of concentration ranges from previous measurements in China. Comparisons indicate that the concentrations of the organic acids at remote sites are lower than those at sites in the vicinity of urban areas. The annual wet depositions of formate and acetate were estimated to be in the ranges of 0.38-4.18 mmol/(m2 x a) and 0.06-5.87 mmol/(m2 x a), respectively, with larger depositions in southern China and smaller depositions in northern China. The relative contributions of the two organic acids to the TFA of precipitation were estimated to be in the range of 0.02%-51.6%, with an overall average of 2.95%. This suggests that although acid rain in China is mainly caused by emissions of sulfur and nitrogen oxides, organic acids can significantly contribute to the acidification of precipitation in some regions and during some periods, hence need to be included in observational studies of acid rain. PMID:20527162

  11. Removal of dicyclohexyl acetic acid from aqueous solution using ultrasound, ozone and their combination.

    PubMed

    Kumar, Pardeep; Headley, John; Peru, Kerry; Bailey, Jon; Dalai, Ajay

    2014-01-01

    Naphthenic acids are a complex mixture of organic components, some of which include saturated alkyl-substituted cycloaliphatic carboxylic acids and acyclic aliphatic acids. They are naturally found in hydrocarbon deposits like oil sand, petroleum, bitumen and crude oil. In this study, the oxidation of a relatively high molecular weight naphthenic acid (Dicyclohexyl acetic acid) was investigated using ozonation, ultrasonication and hydrogen peroxide alone and their combinations. Effects on oxidation of dicyclohexyl acetic acid (DAA) were measured for different concentrations of ozone ranging between 0.7 to 3.3 mg L(-1) and pH in the range 6 to 10. Ultrasonication and hydrogen peroxide alone were not effective to oxidize dicyclohexyl acetic acid, but combining ultrasonication with H2O2 had a significant effect on oxidation of dicyclohexyl acetic acid with maximum removal reaching to 84 ± 2.2% with 81 ± 2.1% reduction in chemical oxygen demand (COD). Synergistic effects were observed for combining ultrasonication with ozonation and resulted in 100% DAA removal with 98 ± 0.8% reduction in COD within 15 min at 3.3 mg L(-1) ozone concentration and 130 Watts ultrasonication power. The reaction conditions obtained for the maximum oxidation of DAA and COD removal were used for the degradation of naphthenic acids mixture extracted from oil sands process water (OSPW). The percentage oxidation of NAs mixture extracted from OSPW was 89.3 ± 1.1% in ozonation and combined ozonation and ultrasonication, but COD removal observed was 65 ± 1.2% and 78 ± 1.4% for ozonation and combined ozonation and ultrasonication treatments, respectively. PMID:25137539

  12. Batch salicylic acid nitration by nitric acid/acetic acid mixture under isothermal, isoperibolic and adiabatic conditions.

    PubMed

    Andreozzi, R; Canterino, M; Caprio, V; Di Somma, I; Sanchirico, R

    2006-12-01

    Runaway phenomena and thermal explosions can originate during the nitration of salicylic acid by means of a nitric acid/acetic acid mixture when the thermal control is lost, mainly as a result of the formation and thermal decomposition of picric acid. The prediction of the behaviour of this system is thus of great importance in view of possible industrial applications and the need to avoid the occurrence of unwanted dangerous events. During a previous investigation a model was developed to simulate its behaviour when the starting concentration of the substrate is too low, thus, preventing the precipitation of poor soluble intermediates. In this work this model is extended to deal with more concentrated systems even in case of a solid phase separating during the process. To this purpose the previously assessed dependence of the solubility of 3-nitro and 5-nitrosalicylic acids upon temperature and nitric acid concentration is included in the model. It is assumed that when 3-nitro and 5-nitrosalicylic acids are partially suspended in the reacting medium a kinetic regime of "dissolution with reaction" is established; that is, the redissolution of these species is a fast process compared to the successive nitration to give dinitroderivatives. Good results are obtained in the comparison of the experimental data with those calculated both in isoperibolic and adiabatic conditions when the revised model is used. PMID:16842908

  13. Trapping social wasps (Hymenoptera: Vespidae) in nurseries with acetic acid and isobutanol

    Technology Transfer Automated Retrieval System (TEKTRAN)

    European hornet (Vespa crabro L.) damages bark of nursery trees, and several vespids sting nursery personnel when disturbed. We tested acetic acid and isobutanol lures in traps for V. crabro spring queens, to determine the seasonality of vespid captures, and compare the efficacy of patterns of trap...

  14. 21 CFR 862.1390 - 5-Hydroxyindole acetic acid/serotonin test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false 5-Hydroxyindole acetic acid/serotonin test system. 862.1390 Section 862.1390 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical...

  15. Detection of Acetic Acid in wine by means of an electronic nose

    NASA Astrophysics Data System (ADS)

    Lozano, Jesús; Álvarez, Fernando; Santos, José Pedro; Horrillo, Carmen

    2011-09-01

    A portable electronic nose (see Fig.1) based on metal oxide semiconductor thin-film sensors has been developed to detect acetic acid present in four types of wines. The wines analyzed are from the same cellar but are made with different varieties of grapes. Data analysis was performed by two pattern recognition methods: principal component analysis (PCA) and Artificial Neural Networks (ANN).

  16. EXTRACTION AND ELECTROSPINNING OF ZEIN EXTRACTED FROM CORN GLUTEN MEAL USING ACETIC ACID

    Technology Transfer Automated Retrieval System (TEKTRAN)

    It has been demonstrated that zein fibers can be produced using the electrospinning technique. Fibers electrospun from acetic acid solution under suitable conditions provide fibers with a more consistent morphology (round 0.5-2.0 micro fibers) compared to fibers produced from aqueous ethanol soluti...

  17. Vinegar (20% acetic acid) broadcast application for broadleaf weed control in spring-transplanted onions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Organic weed control research was conducted in southeast Oklahoma to determine the effect of broadcast over-the-top applications of acetic acid (vinegar) on weed control efficacy, crop injury and onion yields. The experiment included 6 weed control treatments (2 application volumes, 2 hand-weeding ...

  18. Adsorption and Thermal Processing of Glycolaldehyde, Methyl Formate, and Acetic Acid on Graphite at 20 K.

    PubMed

    Burke, Daren J; Puletti, Fabrizio; Woods, Paul M; Viti, Serena; Slater, Ben; Brown, Wendy A

    2015-07-01

    We present the first detailed comparative study of the adsorption and thermal processing of the three astrophysically important C2O2H4 isomers glycolaldehyde, methyl formate, and acetic acid adsorbed on a graphitic grain analogue at 20 K. The ability of the individual molecule to form intermolecular hydrogen bonds is extremely important, dictating the growth modes of the ice on the surface and the measured desorption energies. Methyl formate forms only weak intermolecular bonds and hence wets the graphite surface, forming monolayer, bilayer, and multilayer ices, with the multilayer having a desorption energy of 35 kJ mol(-1). In contrast, glycolaldehyde and acetic acid dewet the surface, forming clusters even at the very lowest coverages. The strength of the intermolecular hydrogen bonding for glycolaldehyde and acetic acid is reflected in their desorption energies (46.8 and 55 kJ mol(-1), respectively), which are comparable to those measured for other hydrogen-bonded species such as water. Infrared spectra show that all three isomers undergo structural changes as a result of thermal processing. In the case of acetic acid and glycolaldehyde, this can be assigned to the formation of well-ordered, crystalline, structures where the molecules form chains of hydrogen-bonded moieties. The data reported here are of relevance to astrochemical studies of hot cores and star-forming regions and can be used to model desorption from interstellar ices during the warm up phase with particular importance for complex organic molecules. PMID:26057183

  19. 40 CFR 721.10448 - Acetic acid, hydroxy- methoxy-, methyl ester, reaction products with substituted alkylamine...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... ester, reaction products with substituted alkylamine (generic). 721.10448 Section 721.10448 Protection... NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10448 Acetic acid, hydroxy- methoxy-, methyl ester, reaction products with substituted alkylamine (generic)....

  20. 40 CFR 721.10448 - Acetic acid, hydroxy- methoxy-, methylester, reaction products with substituted alkylamine...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-, methylester, reaction products with substituted alkylamine (generic). 721.10448 Section 721.10448 Protection... NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10448 Acetic acid, hydroxy- methoxy-, methylester, reaction products with substituted alkylamine (generic)....

  1. 7-Azaindole-3-acetic acid derivatives: potent and selective CRTh2 receptor antagonists.

    PubMed

    Sandham, David A; Adcock, Claire; Bala, Kamlesh; Barker, Lucy; Brown, Zarin; Dubois, Gerald; Budd, David; Cox, Brian; Fairhurst, Robin A; Furegati, Markus; Leblanc, Catherine; Manini, Jodie; Profit, Rachael; Reilly, John; Stringer, Rowan; Schmidt, Alfred; Turner, Katharine L; Watson, Simon J; Willis, Jennifer; Williams, Gareth; Wilson, Caroline

    2009-08-15

    High throughput screening identified a 7-azaindole-3-acetic acid scaffold as a novel CRTh2 receptor antagonist chemotype, which could be optimised to furnish a highly selective compound with good functional potency for inhibition of human eosinophil shape change in whole blood and oral bioavailability in the rat. PMID:19592244

  2. Population dynamics of acetic acid bacteria during traditional wine vinegar production.

    PubMed

    Vegas, Carlos; Mateo, Estibaliz; González, Angel; Jara, Carla; Guillamón, José Manuel; Poblet, Montse; Torija, Ma Jesús; Mas, Albert

    2010-03-31

    The population dynamics of acetic acid bacteria in traditional vinegar production was determined in two independent vinegar plants at both the species and strain level. The effect of barrels made of four different woods upon the population dynamics was also determined. Acetic acid bacteria were isolated on solid media and the species were identified by RFLP-PCR of 16S rRNA genes and confirmed by 16S rRNA gene sequencing, while strains were typed by ERIC-PCR and (GTG)(5)-rep-PCR. The most widely isolated species was Acetobacter pasteurianus, which accounted for 100% of all the isolates during most of the acetification. Gluconacetobacter europaeus only appeared at any notable level at the end of the process in oak barrels from one vinegar plant. The various A. pasteurianus strains showed a clear succession as the concentration of acetic acid increased. In both vinegar plants the relative dominance of different strains was modified as the concentrations of acetic acid increased, and strain diversity tended to reduce at the end of the process. PMID:20117853

  3. 21 CFR 862.1390 - 5-Hydroxyindole acetic acid/serotonin test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false 5-Hydroxyindole acetic acid/serotonin test system. 862.1390 Section 862.1390 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1390...

  4. GENE EXPRESSION PATTERNS OF CD-1 DAY-8 EMBRYO CULTURES EXPOSED TO BROMOCHLORO ACETIC ACID

    EPA Science Inventory

    Gene expression patterns of CD-1 day-8 embryo cultures exposed to bromochloro acetic acid

    Edward D. Karoly?*, Judith E. Schmid* and E. Sidney Hunter III*
    ?Curriculum in Toxicology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina and *Reproductiv...

  5. Molecular Cloning and Biochemical Characterization of Indole-3-acetic Acid Methyltransferase from Poplar (Populus trichocarpa)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Indole-3-acetic acid (IAA) is the most active endogenous auxin involved in various physiological processes in higher plants. Concentrations of IAA in plant tissues are regulated at multiple levels including de novo biosynthesis, degradation, and conjugation/deconjugation. In this paper, we report id...

  6. Improved Butanol-Methanol (BUME) Method by Replacing Acetic Acid for Lipid Extraction of Biological Samples.

    PubMed

    Cruz, Mutya; Wang, Miao; Frisch-Daiello, Jessica; Han, Xianlin

    2016-07-01

    Extraction of lipids from biological samples is a critical step in lipidomics, especially for shotgun lipidomics where lipid extracts are directly infused into a mass spectrometer. The butanol-methanol (BUME) extraction method was originally developed to extract lipids from plasma samples with 1 % acetic acid. Considering some lipids are sensitive to acidic environments, we modified this protocol by replacing acetic acid with lithium chloride solution and extended the modified extraction to tissue samples. Although no significant reduction of plasmalogen levels in the acidic BUME extracts of rat heart samples was found, the modified method was established to extract various tissue samples, including rat liver, heart, and plasma. Essentially identical profiles of the majority of lipid classes were obtained from the extracts of the modified BUME and traditional Bligh-Dyer methods. However, it was found that neither the original, nor the modified BUME method was suitable for 4-hydroxyalkenal species measurement in biological samples. PMID:27245345

  7. Radiolysis of aqueous solutions of acetic acid in the presence of Na-montmorillonite

    NASA Technical Reports Server (NTRS)

    Navarro-Gonzalez, R.; Negron-Mendoza, A.; Ramos, S.; Ponnamperuma, C.

    1990-01-01

    The gamma-irradiation of 0.8 mol dm-3 aqueous, oxygen-free acetic acid solutions was investigated in the presence or absence of Na-montmorillonite. H2, CH4, CO, CO2, and several polycarboxylic acids were formed in all systems. The primary characteristics observed in the latter system were: (1) Higher yield of the decomposition of acetic acid; (2) Lower yield of the formation of polycarboxylic acids; (3) No effect on the formation of methane; (4) Higher yield of the formation of carbon dioxide; and (5) The reduction of Fe3+ in the octahedral sites of Na-montmorillonite. A possible reaction scheme was proposed to account for the observed changes. The results are important in understanding heterogeneous processes in radiation catalysis and might be significant to prebiotic chemistry.

  8. [Long-term and short-term effects of propionic/acetic acid ratios on metabolism of glycogen-accumulating organisms].

    PubMed

    Yao, Ying; Chen, Yin-guang; Ma, Min; Gu, Guo-wei

    2007-09-01

    Three activated sludges enriched with glycogen accumulating organisms (GAO) were acclimatized respectively with different ratios of propionic to acetic acid (i.e. biomass SBR-A, C and E) . The effect of different ratios of propionic/acetic acid on the metabolism of long-term cultivated GAO was investigated. Cultivated with high propionic/acetic acid ratio, GAO consumed less glycogen and synthesized less poly-beta-hydroxyalkanoates (PHA) in the anaerobic phase, and in the aerobic phase accumulated less glycogen and degraded less PHA, and at the same time the microbial growth was lower. When the carbon mole of acetic acid equaled that of propionic acid in the influent, GAO utilized acetic acid faster than propionic acid. Batch tests were carried out with biomass SBR-A and SBR-E to study the transient response of long-term cultivated GAO to short-term change of propionic/acetic acid ratio. The GAO cultivated with a high propionic/acetic acid ratio was able to utilize acetic acid immediately when the concentration of acetic acid in the feed suddenly increased. But when the biomass cultivated with a low propionic/acetic acid ratio was feed with high ratio propionic/acetic acid wastewater, the propionic acid uptake rate was only 41.1% of the rate of the GAO long-term cultivated with high propionic/acetic acid. The sudden increase of propionic/acetic acid ratio could effectively inhibit the metabolism of GAO. PMID:17990541

  9. Analysis of Bacterial Diversity During Acetic Acid Fermentation of Tianjin Duliu Aged Vinegar by 454 Pyrosequencing.

    PubMed

    Peng, Qian; Yang, Yanping; Guo, Yanyun; Han, Ye

    2015-08-01

    The vinegar pei harbors complex bacterial communities. Prior studies revealing the bacterial diversity involved were mainly conducted by culture-dependent methods and PCR-DGGE. In this study, 454 pyrosequencing was used to investigate the bacterial communities in vinegar pei during the acetic acid fermentation (AAF) of Tianjin Duliu aged vinegar (TDAV). The results showed that there were 7 phyla and 24 families existing in the vinegar pei, with 2 phyla (Firmicutes, Protebacteria) and 4 families (Lactobacillaceae, Acetobacteracae, Enterobacteriaceae, Chloroplast) predominating. The genus-level identification revealed that 9 genera were the relatively stable, consistent components in different stages of AAF, including the most abundant genus Lactobacillus followed by Acetobacter and Serratia. Additionally, the bacterial community in the early fermentation stage was more complex than those in the later stages, indicating that the accumulation of organic acids provided an appropriate environment to filter unwanted bacteria and to accelerate the growth of required ones. This study provided basic information of bacterial patterns in vinegar pei and relevant changes during AAF of TDAV, and could be used as references in the following study on the implementation of starter culture as well as the improvement of AAF process. PMID:25903266

  10. Myrrh attenuates oxidative and inflammatory processes in acetic acid-induced ulcerative colitis

    PubMed Central

    Fatani, Amal Jamil; Alrojayee, Fatima Salih; Parmar, Mihir Yogeshkumar; Abuohashish, Hatem Mustafa; Ahmed, Mohammed Mahboobuddin; Al-Rejaie, Salim Salih

    2016-01-01

    The pathogenesis of ulcerative colitis (UC) has been associated with a weakened antioxidant capacity and increased inflammatory processes. Myrrh is traditionally used for the treatment of inflammatory diseases due to its antioxidant and anti-inflammatory properties. The present study aimed to evaluate the effects of myrrh on an experimental rat model of UC. UC was induced in rats using acetic acid (AA) after pre-treatment with myrrh (125, 250 or 500 mg/kg/day) or mesalazine (MES; 300 mg/kg/day) for 7 days. The levels of various inflammatory cytokines, prostaglandin E2 (PGE2) and nitric oxide (NO) in the rat colon tissues were assessed. In addition, the colonic levels of thiobarbituric acid reactive substances (TBARS) and non-protein sulfhydryl groups (NP-SH), as well as the activities of superoxide dismutase (SOD) and catalase (CAT), were estimated. Furthermore, total protein (TP) contents and the levels of DNA and RNA were measured, and histopathological changes in colonic tissues were analyzed. The results indicated that the levels of pro-inflammatory cytokines, PGE2, NO and TBARS were markedly increased. By contrast, the levels of interleukin-10, NP-SH, TP and nucleic acids, and the enzymatic activities of SOD and CAT were significantly decreased in the AA model group. In addition, pretreatment with myrrh and MES was able to attenuate the impaired oxidative stress response and upregulation of inflammatory biomarkers. Furthermore, the enzymatic activities of SOD and CAT were near to normal in the myrrh and MES pretreated groups. The ability of myrrh to protect against UC was further confirmed by histopathological analysis, and the high dose of myrrh exerted an effect comparable to MES. In conclusion, the results of the present study suggested that myrrh has potent therapeutic value in the amelioration of experimental colitis in laboratory animals by downregulating the expression of proinflammatory mediators and improving endogenous antioxidative activities. PMID

  11. Gibbs ensemble Monte Carlo simulation using an optimized potential model: pure acetic acid and a mixture of it with ethylene.

    PubMed

    Zhang, Minhua; Chen, Lihang; Yang, Huaming; Sha, Xijiang; Ma, Jing

    2016-07-01

    Gibbs ensemble Monte Carlo simulation with configurational bias was employed to study the vapor-liquid equilibrium (VLE) for pure acetic acid and for a mixture of acetic acid and ethylene. An improved united-atom force field for acetic acid based on a Lennard-Jones functional form was proposed. The Lennard-Jones well depth and size parameters for the carboxyl oxygen and hydroxyl oxygen were determined by fitting the interaction energies of acetic acid dimers to the Lennard-Jones potential function. Four different acetic acid dimers and the proportions of them were considered when the force field was optimized. It was found that the new optimized force field provides a reasonable description of the vapor-liquid phase equilibrium for pure acetic acid and for the mixture of acetic acid and ethylene. Accurate values were obtained for the saturated liquid density of the pure compound (average deviation: 0.84 %) and for the critical points. The new optimized force field demonstrated greater accuracy and reliability in calculations of the solubility of the mixture of acetic acid and ethylene as compared with the results obtained with the original TraPPE-UA force field. PMID:27324633

  12. 40 CFR 721.304 - Acetic acid, [(5-chloro-8-quinolinyl)oxy-], 1-methyl hexyl ester.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.304 Acetic acid, , 1-methyl hexyl ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as acetic acid, -, 1-methylhexyl ester (PMN...

  13. 40 CFR 721.304 - Acetic acid, [(5-chloro-8-quinolinyl)oxy-], 1-methyl hexyl ester.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.304 Acetic acid, , 1-methyl hexyl ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as acetic acid, -, 1-methylhexyl ester (PMN...

  14. Microbial process for the preparation of acetic acid as well as solvent for its extraction from the fermentation broth

    DOEpatents

    Gaddy, James L.; Clausen, Edgar C.; Ko, Ching-Whan; Wade, Leslie E.; Wikstrom, Carl V.

    2002-01-01

    A modified water-immiscible solvent useful in the extraction of acetic acid from aqueous streams is a substantially pure mixture of isomers of highly branched di-alkyl amines. This solvent is substantially devoid of mono-alkyl amines and alcohols. Solvent mixtures formed of such a modified solvent with a desired cosolvent, preferably a low boiling hydrocarbon which forms an azeotrope with water are useful in the extraction of acetic acid from aqueous gaseous streams. An anaerobic microbial fermentation process for the production of acetic acid employs such solvents, under conditions which limit amide formation by the solvent and thus increase the efficiency of acetic acid recovery. Methods for the direct extraction of acetic acid and the extractive fermentation of acetic acid also employ the modified solvents and increase efficiency of acetic acid production. Such increases in efficiency are also obtained where the energy source for the microbial fermentation contains carbon dioxide and the method includes a carbon dioxide stripping step prior to extraction of acetic acid in solvent.

  15. Microbial process for the preparation of acetic acid as well as solvent for its extraction from the fermentation broth

    DOEpatents

    Gaddy, James L.; Clausen, Edgar C.; Ko, Ching-Whan; Wade, Leslie E.; Wikstrom, Carl V.

    2006-07-11

    A modified water-immiscible solvent useful in the extraction of acetic acid from aqueous streams is a substantially pure mixture of isomers of highly branched di-alkyl amines. This solvent is substantially devoid of mono-alkyl amines and alcohols. Solvent mixtures formed of such a modified solvent with a desired cosolvent, preferably a low boiling hydrocarbon which forms an azeotrope with water are useful in the extraction of acetic acid from aqueous gaseous streams. An anaerobic microbial fermentation process for the production of acetic acid employs such solvents, under conditions which limit amide formation by the solvent and thus increase the efficiency of acetic acid recovery. Methods for the direct extraction of acetic acid and the extractive fermentation of acetic acid also employ the modified solvents and increase efficiency of acetic acid production. Such increases in efficiency are also obtained where the energy source for the microbial fermentation contains carbon dioxide and the method includes a carbon dioxide stripping step prior to extraction of acetic acid in solvent.

  16. CRYSTAL AND MOLECULAR STRUCTURE OF 6,6´-DIMETHOXY-GOSSYPOL:ACETIC ACID (1:1)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    By crystallization from dilute solutions of acetic acid (2-4%) in diethyl ether, acetone, or methyl ethyl ketone, 6,6´-dimethoxy-gossypol forms an inclusion complex with acetic acid in a one-to-one molar ratio. The compound crystallizes in the triclinic P1bar1¯space group and has unit cell dimensio...

  17. Acidic stream mitigation by limestone sand addition

    SciTech Connect

    Brant, D.L.; Marich, A.J. Jr.; Largent, K.L.

    1996-12-31

    The Town Line Run watershed comprises an area of 3,600 wooded acres. The tributaries feeding the stream consist of sandstone springs that do not contribute alkalinity to the watershed, leaving the stream susceptible to acid precipitation. This has a negative affect on Iser`s Run, a native brook trout fishery above the confluence with Town Line Run. The objective in stream liming is to improve water chemistry by increasing pH, alkalinity, and reducing acidity, aluminum, and iron. Introducing crushed limestone directly into a stream from a dump truck is an inexpensive but temporary solution to accomplish this objective. In this type of liming operation, a bed of limestone is spread down the stream channel by the momentum of the stream from the introduction point, rather than manually. Water moving across this bed dissolves the limestone, increasing the pH, alkalinity, and calcium while decreasing the acidity, iron, and aluminum concentrations of the water. The size of the limestone particles is important for this purpose because particles that are too small (<150 microns) will carried away, while particles that are too large (>1000 microns) will remain at the introduction point. Our study placed 80 tons of sand-sized limestone (85% calcite) in the stream channel at a single point. Water samples were collected monthly at the following sites (1) directly upstream of the addition site, (2) 100 yards downstream of the site, and (3) 2500 yards downstream of the site. Other sample locations include (4) upstream and (5) downstream of the Town Line Run- Iser`s Run confluence and the Casselman River upstream (6) and downstream (7) of Town Line Run. The samples were analyzed for pH. Specific conductivity, Alkalinity, Acidity, Iron, Manganese, Aluminum, and Sulfate.

  18. Analysis of the stable carbon isotope composition of formic and acetic acids.

    PubMed

    Lee, Xinqing; Zhang, Like; Huang, Daikuan; An, Ning; Yang, Fang; Jiang, Wei; Fang, Bin

    2013-05-15

    Formic and acetic acids are ubiquitous in the environment and in many biological processes. Analysis of the stable carbon isotope composition (δ(13)C) of formic and acetic acids is important to understanding their biogeochemical cycles. However, it has been faced with poor accuracy and high detection limits due to their low carbon number, high hydrophilicity, and semi-volatility. Here we developed an analytical technique by needle trap and gas chromatography-isotope ratio mass spectrometry (GC-IRMS). The organic acids in aqueous solution were extracted using a NeedlEx needle through purge-and-trap and were analyzed by GC-IRMS for δ(13)C. The procedures incur no isotope fractionation. Defined as the point at which the mean δ(13)C is statistically the same as the given value and the analytical error starts rising, the method's detection limits are 200 and 100 mg/L for formic and acetic acids, respectively, with an uncertainty of approximately 0.5‰ in direct extraction and analysis. They were lowered to 1 mg/L with precision of 0.9‰ after samples were subjected to preconcentration. The method was successfully applied to natural samples as diverse as precipitation, vinegars, ant plasma, and vehicle exhaust, which vary considerably in concentration and matrix of the organic acids. It is applicable to the organic acids in not only aqueous solution but also gaseous phase. PMID:23395975

  19. STABILITY OF MFI ZEOLITE-FILLED PDMS MEMBRANES DURING PERVAPORATIVE ETHANOL RECOVERY FROM AQUEOUS MIXTURES CONTAINING ACETIC ACID

    EPA Science Inventory

    Pervaporation is a potential process for recovering bioethanol produced from biomass fermentation. Fermentation broths contain ethanol, water, and a variety of other compounds, often including carboxylic acids. The effects of acetic acid on long-term pervaporation of aqueous et...

  20. A nitrilo-tri-acetic-acid/acetic acid route for the deposition of epitaxial cerium oxide films as high temperature superconductor buffer layers

    SciTech Connect

    Thuy, T.T.; Lommens, P.; Narayanan, V.; Van de Velde, N.; De Buysser, K.; Herman, G.G.; Cloet, V.; Van Driessche, I.

    2010-09-15

    A water based cerium oxide precursor solution using nitrilo-tri-acetic-acid (NTA) and acetic acid as complexing agents is described in detail. This precursor solution is used for the deposition of epitaxial CeO{sub 2} layers on Ni-5at%W substrates by dip-coating. The influence of the complexation behavior on the formation of transparent, homogeneous solutions and gels has been studied. It is found that ethylenediamine plays an important role in the gelification. The growth conditions for cerium oxide films were Ar-5% gas processing atmosphere, a solution concentration level of 0.25 M, a dwell time of 60 min at 900 {sup o}C and 5-30 min at 1050 {sup o}C. X-ray diffraction (XRD), scanning electron microscope (SEM), atomic force microscopy (AFM), pole figures and spectroscopic ellipsometry were used to characterize the CeO{sub 2} films with different thicknesses. Attenuated total reflection-Fourier transform infrared (ATR-FTIR) was used to determine the carbon residue level in the surface of the cerium oxide film, which was found to be lower than 0.01%. Textured films with a thickness of 50 nm were obtained. - Graphical abstract: Study of the complexation and hydrolysis behavior of Ce{sup 4+} ions in the presence of nitrilo-tri-acetic acid and the subsequent development of an aqueous chemical solution deposition route suited for the processing of textured CeO{sub 2} buffer layers on Ni-W tapes.

  1. Clostridium stain which produces acetic acid from waste gases

    DOEpatents

    Gaddy, James L.

    1997-01-01

    A method and apparatus for converting waste gases from industrial processes such as oil refining, carbon black, coke, ammonia, and methanol production, into useful products. The method includes introducing the waste gases into a bioreactor where they are fermented to various organic acids or alcohols by anaerobic bacteria within the bioreactor. These valuable end products are then recovered, separated and purified. In an exemplary recovery process, the bioreactor raffinate is passed through an extraction chamber into which one or more non-inhibitory solvents are simultaneously introduced to extract the product. Then, the product is separated from the solvent by distillation. Gas conversion rates can be maximized by use of centrifuges, hollow fiber membranes, or other means of ultrafiltration to return entrained anaerobic bacteria from the bioreactor raffinate to the bioreactor itself, thus insuring the highest possible cell concentration.

  2. Clostridium strain which produces acetic acid from waste gases

    DOEpatents

    Gaddy, J.L.

    1997-01-14

    A method and apparatus are disclosed for converting waste gases from industrial processes such as oil refining, carbon black, coke, ammonia, and methanol production, into useful products. The method includes introducing the waste gases into a bioreactor where they are fermented to various organic acids or alcohols by anaerobic bacteria within the bioreactor. These valuable end products are then recovered, separated and purified. In an exemplary recovery process, the bioreactor raffinate is passed through an extraction chamber into which one or more non-inhibitory solvents are simultaneously introduced to extract the product. Then, the product is separated from the solvent by distillation. Gas conversion rates can be maximized by use of centrifuges, hollow fiber membranes, or other means of ultrafiltration to return entrained anaerobic bacteria from the bioreactor raffinate to the bioreactor itself, thus insuring the highest possible cell concentration. 4 figs.

  3. In situ FTIR investigation of acetic acid electrooxidation on carbon supported Pt-Sn based trimetallic catalysts: Influence of the nature of the third metal

    NASA Astrophysics Data System (ADS)

    Beyhan, Seden; Léger, Jean-Michel; Kadırgan, Figen

    2014-12-01

    The effect of adding a third metal (Ni, Co, Pd, Rh) to Pt-Sn/C catalyst has been investigated for the adsorption and oxidation of acetic acid in acidic medium using in situ Fourier transform infrared (FTIR) spectroscopy. The results showed that the decomposition of acetic acid on the surface leads to the formation of different intermediate species and products such as acetate, acetyl, carbonate, CO and CO2. The reaction pathway of CO2 production proceeds via the formation of acetyl or carbonate through surface acetate species. It has been found that the selectivity of the acetate was enhanced by the addition of any third metal. However, the presence of Pd or Co increases the relative intensity of IR band for CO2. This is probably due to success in facilitating of the Csbnd C bond cleavage of acetyl. On the other hand, the conversion of acetate to carbonate is strongly affected by the adsorbed water, as is evident from the pronounced changes in the OH stretching region with the presence of Pd or Ni.

  4. Transport of the two natural auxins, indole-3-butyric acid and indole-3-acetic acid, in Arabidopsis

    NASA Technical Reports Server (NTRS)

    Rashotte, Aaron M.; Poupart, Julie; Waddell, Candace S.; Muday, Gloria K.; Brown, C. S. (Principal Investigator)

    2003-01-01

    Polar transport of the natural auxin indole-3-acetic acid (IAA) is important in a number of plant developmental processes. However, few studies have investigated the polar transport of other endogenous auxins, such as indole-3-butyric acid (IBA), in Arabidopsis. This study details the similarities and differences between IBA and IAA transport in several tissues of Arabidopsis. In the inflorescence axis, no significant IBA movement was detected, whereas IAA is transported in a basipetal direction from the meristem tip. In young seedlings, both IBA and IAA were transported only in a basipetal direction in the hypocotyl. In roots, both auxins moved in two distinct polarities and in specific tissues. The kinetics of IBA and IAA transport appear similar, with transport rates of 8 to 10 mm per hour. In addition, IBA transport, like IAA transport, is saturable at high concentrations of auxin, suggesting that IBA transport is protein mediated. Interestingly, IAA efflux inhibitors and mutations in genes encoding putative IAA transport proteins reduce IAA transport but do not alter IBA movement, suggesting that different auxin transport protein complexes are likely to mediate IBA and IAA transport. Finally, the physiological effects of IBA and IAA on hypocotyl elongation under several light conditions were examined and analyzed in the context of the differences in IBA and IAA transport. Together, these results present a detailed picture of IBA transport and provide the basis for a better understanding of the transport of these two endogenous auxins.

  5. [Conversion of acetic acid to methane by thermophiles]. Progress report, May 15, 1989--May 14, 1993

    SciTech Connect

    Zinder, S.H.

    1993-06-01

    The primary goal of this project is to obtain a better understanding of thermophilic microorganisms which convert acetic acid to CH{sub 4}. The previous funding period represents a departure from earlier research in this laboratory, which was more physiological and ecological. The present work is centered on the biochemistry of the thermophile Methanothrix sp. strain CALS-1. this organism presents a unique opportunity, with its purity and relatively rapid growth, to do comparative biochemical studies with the other major acetotrophic genus Methanosarcina. We previously found that Methanothrix is capable of using acetate at concentrations 100 fold lower than Methanosarcina. This finding suggests that there are significant differences in the pathways of methanogenesis from acetate in the two genera.

  6. Breath concentration of acetic acid vapour is elevated in patients with cystic fibrosis.

    PubMed

    Smith, David; Sovová, Kristýna; Dryahina, Kseniya; Doušová, Tereza; Dřevínek, Pavel; Španěl, Patrik

    2016-01-01

    A study has been carried out of the volatile organic compounds present in the exhaled breath of 58 cystic fibrosis (CF) patients. An important observation is that the acetic acid vapour concentration measured by selected ion flow tube mass spectrometry (SIFT-MS) is significantly elevated in the exhaled breath of CF patients, independent of the Pseudomonas aeruginosa (PA) infection status (PA-infected median 170 ppbv; PA-negative median 182 ppbv), compared to that of healthy controls (median 48 ppbv). The cause for this may be decreased pH of the mucus lining the CF airways. Thus, we speculate that non-invasive measurement of breath acetic acid concentration could serve as an indicator of the acidity of the CF airways mucosa. PMID:27184114

  7. Metabolic pathway engineering based on metabolomics confers acetic and formic acid tolerance to a recombinant xylose-fermenting strain of Saccharomyces cerevisiae

    PubMed Central

    2011-01-01

    Background The development of novel yeast strains with increased tolerance toward inhibitors in lignocellulosic hydrolysates is highly desirable for the production of bio-ethanol. Weak organic acids such as acetic and formic acids are necessarily released during the pretreatment (i.e. solubilization and hydrolysis) of lignocelluloses, which negatively affect microbial growth and ethanol production. However, since the mode of toxicity is complicated, genetic engineering strategies addressing yeast tolerance to weak organic acids have been rare. Thus, enhanced basic research is expected to identify target genes for improved weak acid tolerance. Results In this study, the effect of acetic acid on xylose fermentation was analyzed by examining metabolite profiles in a recombinant xylose-fermenting strain of Saccharomyces cerevisiae. Metabolome analysis revealed that metabolites involved in the non-oxidative pentose phosphate pathway (PPP) [e.g. sedoheptulose-7-phosphate, ribulose-5-phosphate, ribose-5-phosphate and erythrose-4-phosphate] were significantly accumulated by the addition of acetate, indicating the possibility that acetic acid slows down the flux of the pathway. Accordingly, a gene encoding a PPP-related enzyme, transaldolase or transketolase, was overexpressed in the xylose-fermenting yeast, which successfully conferred increased ethanol productivity in the presence of acetic and formic acid. Conclusions Our metabolomic approach revealed one of the molecular events underlying the response to acetic acid and focuses attention on the non-oxidative PPP as a target for metabolic engineering. An important challenge for metabolic engineering is identification of gene targets that have material importance. This study has demonstrated that metabolomics is a powerful tool to develop rational strategies to confer tolerance to stress through genetic engineering. PMID:21219616

  8. Formic and acetic acid over the central Amazon region, Brazil. I - Dry season

    NASA Technical Reports Server (NTRS)

    Andreae, M. O.; Andreae, T. W.; Talbot, R. W.; Harriss, R. C.

    1988-01-01

    The concentrations of formic and acetic acids in the gas phase, atmospheric aerosol, and rainwater samples collected in Amazonia at ground level and in the atmosphere during the Amazon Boundary Layer Experiment in July/August 1985 were analyzed by ion exchange chromatography. The diurnal behavior of both acids at ground level and their vertical distribution in the forest canopy point to the existence of vegetative sources as well as to production by chemical reactions in the atmosphere. The concentrations of formic and acetic acids in the gas phase were about 2 orders of magnitude higher than the corresponding concentrations in the atmospheric aerosol. In rainwater, the total formate and acetate represented about one half of the anion equivalents, in contrast to less than 10 percent of the soluble anionic equivalents contributed by these acids in the atmospheric aerosol. The observed levels of these ions in rainwater are considered to be the result of a combination of chemical reactions in hydrometeors and the scavenging of the gaseous acids by cloud droplets.

  9. Ulcer healing activity of Mumijo aqueous extract against acetic acid induced gastric ulcer in rats

    PubMed Central

    Shahrokhi, Nader; Keshavarzi, Zakieh; Khaksari, Mohammad

    2015-01-01

    Objective: Gastric ulcer is an important clinical problem, chiefly due to extensive use of some drugs. The aim was to assess the activity of Mumijo extract (which is used in traditional medicine) against acetic acid induced gastric ulcer in rats. Materials and Methods: The aqueous extract of Mumijo was prepared. Animals were randomly (n = 10) divided into four groups: Control, sham-operated group (received 0.2 ml of acetic acid to induce gastric ulcer), Mumijo (100 mg/kg/daily) were given for 4 days postacetic acid administration, and ranitidine group (20 mg/kg). The assessed parameters were pH and pepsin levels (by Anson method) of gastric contents and gastric histopathology. Ranitidine was used as reference anti-ulcer drug. Results: The extract (100 mg/kg/daily, p.o.) inhibited acid acetic-induced gastric ulceration by elevating its pH versus sham group (P < 0.01) and decreasing the pepsin levels compared to standard drug, ranitidine (P < 0.05). The histopathology data showed that the treatment with Mumijo extract had a significant protection against all mucosal damages. Conclusion: Mumijo extract has potent antiulcer activity. Its anti-ulcer property probably acts via a reduction in gastric acid secretion and pepsin levels. The obtained results support the use of this herbal material in folk medicine. PMID:25709338

  10. The Aerobic Oxidation of Bromide to Dibromine Catalyzed by Homogeneous Oxidation Catalysts and Initiated by Nitrate in Acetic Acid

    SciTech Connect

    Partenheimer, Walt; Fulton, John L.; Sorensen, Christina M.; Pham, Van Thai; Chen, Yongsheng

    2014-06-01

    A small amount of nitrate, ~0.002 molal, initiates the Co/Mn catalyzed aerobic oxidation of bromide compounds (HBr,NaBr,LiBr) to dibromine in acetic acid at room temperature. At temperatures 40oC or less , the reaction is autocatalytic. Co(II) and Mn(II) themselves and mixed with ionic bromide are known homogeneous oxidation catalysts. The reaction was discovered serendipitously when a Co/Br and Co/Mn/Br catalyst solution was prepared for the aerobic oxidation of methyaromatic compounds and the Co acetate contained a small amount of impurity i.e. nitrate. The reaction was characterized by IR, UV-VIS, MALDI and EXAFS spectroscopies and the coordination chemistry is described. The reaction is inhibited by water and its rate changed by pH. The change in these variables, as well as others, are identical to those observed during homogeneous, aerobic oxidation of akylaromatics. A mechanism is proposed. Accidental addition of a small amount of nitrate compound into a Co/Mn/Br/acetic acid mixture in a large, commercial feedtank is potentially dangerous.

  11. A solvent extraction approach to recover acetic acid from mixed waste acids produced during semiconductor wafer process.

    PubMed

    Shin, Chang-Hoon; Kim, Ju-Yup; Kim, Jun-Young; Kim, Hyun-Sang; Lee, Hyang-Sook; Mohapatra, Debasish; Ahn, Jae-Woo; Ahn, Jong-Gwan; Bae, Wookeun

    2009-03-15

    Recovery of acetic acid (HAc) from the waste etching solution discharged from silicon wafer manufacturing process has been attempted by using solvent extraction process. For this purpose 2-ethylhexyl alcohol (EHA) was used as organic solvent. In the pre-treatment stage >99% silicon and hydrofluoric acid was removed from the solution by precipitation. The synthesized product, Na(2)SiF(6) having 98.2% purity was considered of commercial grade having good market value. The waste solution containing 279 g/L acetic acid, 513 g/L nitric acid, 0.9 g/L hydrofluoric acid and 0.030 g/L silicon was used for solvent extraction study. From the batch test results equilibrium conditions for HAc recovery were optimized and found to be 4 stages of extraction at an organic:aqueous (O:A) ratio of 3, 4 stages of scrubbing and 4 stages of stripping at an O:A ratio of 1. Deionized water (DW) was used as stripping agent to elute HAc from organic phase. In the whole batch process 96.3% acetic acid recovery was achieved. Continuous operations were successfully conducted for 100 h using a mixer-settler to examine the feasibility of the extraction system for its possible commercial application. Finally, a complete process flowsheet with material balance for the separation and recovery of HAc has been proposed. PMID:18639982

  12. Screening and characterization of ethanol-tolerant and thermotolerant acetic acid bacteria from Chinese vinegar Pei.

    PubMed

    Chen, Yang; Bai, Ye; Li, Dongsheng; Wang, Chao; Xu, Ning; Hu, Yong

    2016-01-01

    Acetic acid bacteria (AAB) are important microorganisms in the vinegar industry. However, AAB have to tolerate the presence of ethanol and high temperatures, especially in submerged fermentation (SF), which inhibits AAB growth and acid yield. In this study, seven AAB that are tolerant to temperatures above 40 °C and ethanol concentrations above 10% (v/v) were isolated from Chinese vinegar Pei. All the isolated AAB belong to Acetobacter pasteurianus according to 16S rDNA analysis. Among all AAB, AAB4 produced the highest acid yield under high temperature and ethanol test conditions. At 4% ethanol and 30-40 °C temperatures, AAB4 maintained an alcohol-acid transform ratio of more than 90.5 %. High alcohol-acid transform ratio was still maintained even at higher temperatures, namely, 87.2, 77.1, 14.5 and 2.9% at 41, 42, 43 and 44 °C, respectively. At 30 °C and different initial ethanol concentrations (4-10%), the acid yield by AAB4 increased gradually, although the alcohol-acid transform ratio decreased to some extent. However, 46.5, 8.7 and 0.9% ratios were retained at ethanol concentrations of 11, 12 and 13%, respectively. When compared with AS1.41 (an AAB widely used in China) using a 10 L fermentor, AAB4 produced 42.0 g/L acetic acid at 37 °C with 10% ethanol, whereas AS1.41 almost stopped producing acetic acid. In conclusion, these traits suggest that AAB4 is a valuable strain for vinegar production in SF. PMID:26712629

  13. Resistance of Streptococcus bovis to acetic acid at low pH: Relationship between intracellular pH and anion accumulation

    SciTech Connect

    Russell, J.B. )

    1991-01-01

    Streptococcus bovis JB1, an acid-tolerant ruminal bacterium, was able to grown at pHs from 6.7 to 4.5, and 100 mM acetate had little effect on growth rate or proton motive force across the cell membrane. When S. bovis was grown in glucose-limited chemostats at pH 5.2, the addition of sodium acetate (as much as 100 mM) had little effect on the production of bacterial protein. At higher concentrations of sodium acetate (100 to 360 mM), production of bacterial protein declined, but this decrease could largely be explained by a shift in fermentation products (acetate, formate, and ethanol production to lactate production) and a decline in ATP production (3 ATP per glucose versus 2 ATP per glucose). Y{sub ATP} (grams of cells per mole at ATP) was not decreased significantly even by high concentrations of acetate. Cultures supplemented with 100 mM sodium acetate took up ({sup 14}C)acetate and ({sup 14}C)benzoate in accordance with the Henderson-Hasselbalch equation and gave similar estimates of intracellular pH. As the extracellular pH declined, S. bovis allowed its intracellular pH to decrease and maintained a relatively constant pH gradient across the cell membrane (0.9 unit). The decrease in intracellular pH prevented S. bovis from accumulating large amounts of acetate anion. On the basis of these results it did not appear that acetate was acting as an uncoupler. The sensitivity of other bacteria to volatile fatty acids at low pH is explained most easily by a high transmembrane pH gradient and anion accumulation.

  14. Resistance of Streptococcus bovis to acetic acid at low pH: relationship between intracellular pH and anion accumulation.

    PubMed Central

    Russell, J B

    1991-01-01

    Streptococcus bovis JB1, an acid-tolerant ruminal bacterium, was able to grow at pHs from 6.7 to 4.5, and 100 mM acetate had little effect on growth rate or proton motive force across the cell membrane. When S. bovis was grown in glucose-limited chemostats at pH 5.2, the addition of sodium acetate (as much as 100 mM) had little effect on the production of bacterial protein. At higher concentrations of sodium acetate (100 to 360 mM), production of bacterial protein declined, but this decrease could largely be explained by a shift in fermentation products (acetate, formate, and ethanol production to lactate production) and a decline in ATP production (3 ATP per glucose versus 2 ATP per glucose). YATP (grams of cells per mole of ATP) was not decreased significantly even by high concentrations of acetate. Cultures supplemented with 100 mM sodium acetate took up [14C]acetate and [14C]benzoate in accordance with the Henderson-Hasselbalch equation and gave similar estimates of intracellular pH. As the extracellular pH declined, S. bovis allowed its intracellular pH to decrease and maintained a relatively constant pH gradient across the cell membrane (0.9 unit). The decrease in intracellular pH prevented S. bovis from accumulating large amounts of acetate anion. On the basis of these results it did not appear that acetate was acting as an uncoupler. The sensitivity of other bacteria to volatile fatty acids at low pH is explained most easily by a high transmembrane pH gradient and anion accumulation. PMID:2036013

  15. Analysis of a pyruvic acid acetal-containing polysaccharide by the reductive-cleavage method.

    PubMed

    Zeller, S G; Gray, G R

    1991-04-24

    The applicability of the reductive-cleavage method to the analysis of polysaccharides bearing pyruvic acid acetals has been demonstrated. Direct reductive cleavage of fully methylated gum xanthan yielded the expected products, including 1,5-anhydro-4,6-O-[(S)-1-methoxycarbonylethylidene]-2,3-di-O-methy l-D- mannitol. The latter product was not observed when reductive cleavage was performed subsequent to reduction of ester groups in the fully methylated polysaccharide and mild hydrolysis to remove pyruvic acid acetal substituents. Instead, the latter experiment yielded 1,5-anhydro-2,3-di-O-methyl-D-mannitol, establishing the presence in the polysaccharide of terminal (nonreducing) D-mannopyranosyl groups bearing 4,6-O-(1-carboxyethylidene) substituents. The products of reductive cleavage were characterized, where appropriate, by comparison of the gas chromatographic retention times and chemical ionization- and electron ionization-mass spectra of their acetates to those of authentic standards. Alternatively, the products of reductive cleavage could be characterized without resort to comparison with authentic standards by analysis of the 1H-n.m.r. spectra of their benzoates, which were obtained in pure form by high-performance liquid chromatography. By either method of product characterization, this two-step procedure of analysis reveals the presence of pyruvic-acetal residues in polysaccharides and establishes both the identity of the sugar residue to which they are attached and their positions of attachment. PMID:1769016

  16. Influence of Acidic pH on Hydrogen and Acetate Production by an Electrosynthetic Microbiome

    PubMed Central

    LaBelle, Edward V.; Marshall, Christopher W.; Gilbert, Jack A.; May, Harold D.

    2014-01-01

    Production of hydrogen and organic compounds by an electrosynthetic microbiome using electrodes and carbon dioxide as sole electron donor and carbon source, respectively, was examined after exposure to acidic pH (∼5). Hydrogen production by biocathodes poised at −600 mV vs. SHE increased>100-fold and acetate production ceased at acidic pH, but ∼5–15 mM (catholyte volume)/day acetate and>1,000 mM/day hydrogen were attained at pH ∼6.5 following repeated exposure to acidic pH. Cyclic voltammetry revealed a 250 mV decrease in hydrogen overpotential and a maximum current density of 12.2 mA/cm2 at −765 mV (0.065 mA/cm2 sterile control at −800 mV) by the Acetobacterium-dominated community. Supplying −800 mV to the microbiome after repeated exposure to acidic pH resulted in up to 2.6 kg/m3/day hydrogen (≈2.6 gallons gasoline equivalent), 0.7 kg/m3/day formate, and 3.1 kg/m3/day acetate ( = 4.7 kg CO2 captured). PMID:25333313

  17. Obestatin Accelerates the Healing of Acetic Acid-Induced Colitis in Rats

    PubMed Central

    Matuszyk, Aleksandra; Ceranowicz, Piotr; Warzecha, Zygmunt; Cieszkowski, Jakub; Bonior, Joanna; Jaworek, Jolanta; Kuśnierz-Cabala, Beata; Konturek, Peter; Ambroży, Tadeusz; Dembiński, Artur

    2016-01-01

    Obestatin, a 23-amino acid peptide derived from the proghrelin, has been shown to exhibit some protective and therapeutic effects in the gut. The aim of present study was to determine the effect of obestatin administration on the course of acetic acid-induced colitis in rats. Materials and Methods. Studies have been performed on male Wistar rats. Colitis was induced by a rectal enema with 3.5% acetic acid solution. Obestatin was administered intraperitoneally twice a day at a dose of 8 nmol/kg, starting 24 h after the induction of colitis. Seven or 14 days after the induction of colitis, the healing rate of the colon was evaluated. Results. Treatment with obestatin after induction of colitis accelerated the healing of colonic wall damage and this effect was associated with a decrease in the colitis-evoked increase in mucosal activity of myeloperoxidase and content of interleukin-1β. Moreover, obestatin administration significantly reversed the colitis-evoked decrease in mucosal blood flow and DNA synthesis. Conclusion. Administration of exogenous obestatin exhibits therapeutic effects in the course of acetic acid-induced colitis and this effect is related, at least in part, to the obestatin-evoked anti-inflammatory effect, an improvement of local blood flow, and an increase in cell proliferation in colonic mucosa. PMID:26798415

  18. Influence of acidic pH on hydrogen and acetate production by an electrosynthetic microbiome

    SciTech Connect

    LaBelle, Edward V.; Marshall, Christopher W.; Gilbert, Jack A.; May, Harold D.; Battista, John R.

    2014-10-15

    Production of hydrogen and organic compounds by an electrosynthetic microbiome using electrodes and carbon dioxide as sole electron donor and carbon source, respectively, was examined after exposure to acidic pH (~5). Hydrogen production by biocathodes poised at -600 mV vs. SHE increased>100-fold and acetate production ceased at acidic pH, but ~5–15 mM (catholyte volume)/day acetate and>1,000 mM/day hydrogen were attained at pH ~6.5 following repeated exposure to acidic pH. Cyclic voltammetry revealed a 250 mV decrease in hydrogen overpotential and a maximum current density of 12.2 mA/cm2 at -765 mV (0.065 mA/cm2 sterile control at -800 mV) by the Acetobacterium-dominated community. Supplying -800 mV to the microbiome after repeated exposure to acidic pH resulted in up to 2.6 kg/m3/day hydrogen (≈2.6 gallons gasoline equivalent), 0.7 kg/m3/day formate, and 3.1 kg/m3/day acetate ( = 4.7 kg CO2 captured).

  19. Influence of acidic pH on hydrogen and acetate production by an electrosynthetic microbiome

    DOE PAGESBeta

    LaBelle, Edward V.; Marshall, Christopher W.; Gilbert, Jack A.; May, Harold D.; Battista, John R.

    2014-10-15

    Production of hydrogen and organic compounds by an electrosynthetic microbiome using electrodes and carbon dioxide as sole electron donor and carbon source, respectively, was examined after exposure to acidic pH (~5). Hydrogen production by biocathodes poised at -600 mV vs. SHE increased>100-fold and acetate production ceased at acidic pH, but ~5–15 mM (catholyte volume)/day acetate and>1,000 mM/day hydrogen were attained at pH ~6.5 following repeated exposure to acidic pH. Cyclic voltammetry revealed a 250 mV decrease in hydrogen overpotential and a maximum current density of 12.2 mA/cm2 at -765 mV (0.065 mA/cm2 sterile control at -800 mV) by the Acetobacterium-dominatedmore » community. Supplying -800 mV to the microbiome after repeated exposure to acidic pH resulted in up to 2.6 kg/m3/day hydrogen (≈2.6 gallons gasoline equivalent), 0.7 kg/m3/day formate, and 3.1 kg/m3/day acetate ( = 4.7 kg CO2 captured).« less

  20. Negative Pressure Wound Therapy of Chronically Infected Wounds Using 1% Acetic Acid Irrigation

    PubMed Central

    Lee, Byeong Ho; Lee, Hye Kyung; Kim, Hyoung Suk; Moon, Min Seon; Suh, In Suck

    2015-01-01

    Background Negative-pressure wound therapy (NPWT) induces angiogenesis and collagen synthesis to promote tissue healing. Although acetic acid soaks normalize alkali wound conditions to raise tissue oxygen saturation and deconstruct the biofilms of chronic wounds, frequent dressing changes are required. Methods Combined use of NPWT and acetic acid irrigation was assessed in the treatment of chronic wounds, instilling acetic acid solution (1%) beneath polyurethane membranes twice daily for three weeks under continuous pressure (125 mm Hg). Clinical photographs, pH levels, cultures, and debrided fragments of wounds were obtained pre- and posttreatment. Tissue immunostaining (CD31, Ki-67, and CD45) and reverse transcription-polymerase chain reaction (vascular endothelial growth factor [VEGF], vascular endothelial growth factor receptor [VEGFR]; procollagen; hypoxia-inducible factor 1 alpha [HIF-1-alpha]; matrix metalloproteinase [MMP]-1,-3,-9; and tissue inhibitor of metalloproteinase [TIMP]) were also performed. Results Wound sizes tended to diminish with the combined therapy, accompanied by drops in wound pH (weakly acidic or neutral) and less evidence of infection. CD31 and Ki-67 immunostaining increased (P<0.05) post-treatment, as did the levels of VEGFR, procollagen, and MMP-1 (P<0.05), whereas the VEGF, HIF-1-alpha, and MMP-9/TIMP levels declined (P<0.05). Conclusions By combining acetic acid irrigation with negative-pressure dressings, both the pH and the size of chronic wounds can be reduced and infections be controlled. This approach may enhance angiogenesis and collagen synthesis in wounds, restoring the extracellular matrix. PMID:25606491

  1. Protective Effect of Cod (Gadus macrocephalus) Skin Collagen Peptides on Acetic Acid-Induced Gastric Ulcer in Rats.

    PubMed

    Niu, Huina; Wang, Zhicong; Hou, Hu; Zhang, Zhaohui; Li, Bafang

    2016-07-01

    This research was performed to explore the protective effect of cod skin collagen peptides (CCP) on gastric ulcer induced by acetic acid. The CCP were fractionated into low molecular CCP (LMCCP, Mw < 3 kDa) and high molecular CCP (HMCCP, Mw > 3 kDa). In HMCCP and LMCCP, glycine of accounted for about one-third of the total amino acids without cysteine and tryptophan, and hydrophobic amino acids accounted for about 50%. After 21 d CCP treatment (60 or 300 mg/kg, p.o./daily), the healing effects on acetic acid-induced gastric ulcers were evaluated by macroscopic measure, microscopic measure, and immune histochemistry. Moreover, the expression levels of the growth factors, such as vascular endothelial growth factor, epidermal growth factor, transforming growth factor β1 (TGFβ1), and the heat shock protein 70 (HSP70) was detected. The results showed that both LMCCP and HMCCP could significantly decrease the ulcer areas and promote the healing of the lesions. They also could improve the levels of hexosamine, glutathione, superoxide dismutase, and glutathione peroxidase, and reduce the content of malondialdehyde and inducible nitric oxide synthase. In addition, the expression level of TGFβ1 gene and HSP70 mRNA was significantly improved by the treatment. It suggested that CCP could be able to improve symptoms of gastric ulcer and probably be used in the treatment of gastric ulcer. PMID:27219644

  2. Main and interaction effects of acetic acid, furfural, and p-hydroxybenzoic acid on growth and ethanol productivity of yeasts

    SciTech Connect

    Palmqvist, E.; Grage, H.; Meinander, N.Q.; Hahn-Haegerdal, B.

    1999-04-05

    The influence of the factors acetic acid, furfural, and p-hydroxybenzoic acid on the ethanol yield (Y{sub EtOH}) of Saccharomyces cerevisiae, bakers` yeast, S. cerevisiae ATCC 96581, and Candida shehatae NJ 23 was investigated using a 2{sup 3}-full factorial design with 3 centerpoints. The results indicated that acetic acid inhibited the fermentation by C. shehatae NJ 23 markedly more than by bakers` yeast, whereas no significant difference in tolerance towards the compounds was detected between the S. cerevisiae strains. Furfural and the lignin derived compound p-hydroxybenzoic acid did not affect any of the yeasts at the cell mass concentration used. The results indicated that the linear model was not adequate to describe the experimental data. Based on the results from the 2{sup 3}-full factorial experiment, an extended experiment was designed based on a central composite design to investigate the influence of the factors on the specific growth rate ({mu}), biomass yield (Y{sub x}), volumetric ethanol productivity (Q{sub EtOH}), and Y{sub EtOH}. Bakers` yeast was chosen in the extended experiment due to its better tolerance towards acetic acid, which makes it a more interesting organism for use in industrial fermentations of lignocellulosic hydrolysates.

  3. Toxicity of long chain fatty acids towards acetate conversion by Methanosaeta concilii and Methanosarcina mazei.

    PubMed

    Silva, Sérgio A; Salvador, Andreia F; Cavaleiro, Ana J; Pereira, M Alcina; Stams, Alfons J M; Alves, M Madalena; Sousa, Diana Z

    2016-07-01

    Long-chain fatty acids (LCFA) can inhibit methane production by methanogenic archaea. The effect of oleate and palmitate on pure cultures of Methanosaeta concilii and Methanosarcina mazei was assessed by comparing methane production rates from acetate before and after LCFA addition. For both methanogens, a sharp decrease in methane production (> 50%) was observed at 0.5 mmol L(-1) oleate, and no methane was formed at concentrations higher than 2 mmol L(-1) oleate. Palmitate was less inhibitory than oleate, and M. concilii was more tolerant to palmitate than M. mazei, with 2 mmol L(-1) palmitate causing 11% and 64% methanogenic inhibition respectively. This study indicates that M. concilii and M. mazei tolerate LCFA concentrations similar to those previously described for hydrogenotrophic methanogens. In particular, the robustness of M. concilii might contribute to the observed prevalence of Methanosaeta species in anaerobic bioreactors used to treat LCFA-rich wastewater. PMID:27273786

  4. Separation of macromolecular proteins and removal of humic acid by cellulose acetate modified UF membranes.

    PubMed

    Kanagaraj, P; Nagendran, A; Rana, D; Matsuura, T

    2016-08-01

    Surface modifying macromolecules (SMMs) were synthesized with various polyurethane pre polymers end-capped with different groups and blended into the casting solution of cellulose acetate (CA) to prepare surface modified ultra-filtration (UF) membranes for water filtration applications. The surface modification of the CA membranes was confirmed by the FTIR and static contact angle (SCA) measurements. The membranes so prepared had the typical characteristics of UF membranes as confirmed by scanning electron microscopy (SEM). Membrane properties were studied in terms of membrane compaction, percentage water content (%WC), pure water flux (PWF), membrane hydraulic resistance (Rm), molecular weight cut-off (MWCO), average pore size and porosity. The result showed that PWF, %WC, MWCO and pore size increased whereas the Rm decreased by the addition of SMMs. The significant effect of SMMs on the fouling by humic acid (HA) was also observed. It was found that the cSMM-3 membrane, in which SMM was synthesized with diethylene glycol (DEG) and hydroxyl benzene sulfonate (HBS) was blended, had the highest flux recovery ratio FRR (84.6%), as well as the lowest irreversible fouling (15.4%), confirming their improved antifouling properties. Thus, the SMM modified CA membranes had proven, to play an important role in the water treatment by UF. PMID:27118046

  5. Determination of Unknown Concentrations of Sodium Acetate Using the Method of Standard Addition and Proton NMR: An Experiment for the Undergraduate Analytical Chemistry Laboratory

    ERIC Educational Resources Information Center

    Rajabzadeh, Massy

    2012-01-01

    In this experiment, students learn how to find the unknown concentration of sodium acetate using both the graphical treatment of standard addition and the standard addition equation. In the graphical treatment of standard addition, the peak area of the methyl peak in each of the sodium acetate standard solutions is found by integration using…

  6. Soil washing of chromium- and cadmium-contaminated sludge using acids and ethylenediaminetetra acetic acid chelating agent.

    PubMed

    Gitipour, Saeid; Ahmadi, Soheil; Madadian, Edris; Ardestani, Mojtaba

    2016-01-01

    In this research, the effect of soil washing in the removal of chromium- and cadmium-contaminated sludge samples collected from Pond 2 of the Tehran Oil Refinery was investigated. These metals are considered as hazardous substances for human health and the environment. The carcinogenicity of chromate dust has been established for a long time. Cadmium is also a potential environmental toxicant. This study was carried out by collecting sludge samples from different locations in Pond 2. Soil washing was conducted to treat the samples. Chemical agents, such as acetic acid, ethylenediaminetetra acetic acid (EDTA) and hydrochloric acid, were used as washing solutions to remove chromium and cadmium from sludge samples. The results of this study indicated that the highest removal efficiencies from the sludge samples were achieved using a 0.3 M HCl solution with 82.69% and 74.47% for chromium and cadmium, respectively. EDTA (0.1 M) in the best condition extracted 66.81% of cadmium and 72.52% of chromium from the sludges. The lowest efficiency values for the samples, however, were achieved using 3 M acetic acid with 41.7% and 46.96% removals for cadmium and chromium, respectively. The analysis of washed sludge indicated that the heavy metals removal decreased in the order of 3 M acetic acid < 0.1 M EDTA<0.3 M HCl, thus hydrochloric acid appears to offer a greater potential as a washing agent in remediating the sludge samples. PMID:26599728

  7. Palladium-Catalyzed α-Arylation of Aryl Acetic Acid Derivatives via Dienolate Intermediates with Aryl Chlorides and Bromides

    PubMed Central

    2016-01-01

    To date, examples of α-arylation of carboxylic acids remain scarce. Using a deprotonative cross-coupling process (DCCP), a method for palladium-catalyzed γ-arylation of aryl acetic acids with aryl halides has been developed. This protocol is applicable to a wide range of aryl bromides and chlorides. A procedure for the palladium-catalyzed α-arylation of styryl acetic acids is also described. PMID:25582024

  8. Unnatural reactive amino acid genetic code additions

    SciTech Connect

    Deiters, Alexander; Cropp, T. Ashton; Chin, Jason W.; Anderson, J. Christopher; Schultz, Peter G.

    2011-08-09

    This invention provides compositions and methods for producing translational components that expand the number of genetically encoded amino acids in eukaryotic cells. The components include orthogonal tRNAs, orthogonal aminoacyl-tRNAsyn-thetases, pairs of tRNAs/synthetases and unnatural amino acids. Proteins and methods of producing proteins with unnatural amino acids in eukaryotic cells are also provided.

  9. Unnatural reactive amino acid genetic code additions

    SciTech Connect

    Deiters, Alexander; Cropp, Ashton T; Chin, Jason W; Anderson, Christopher J; Schultz, Peter G

    2013-05-21

    This invention provides compositions and methods for producing translational components that expand the number of genetically encoded amino acids in eukaryotic cells. The components include orthogonal tRNAs, orthogonal aminoacyl-tRNA synthetases, pairs of tRNAs/synthetases and unnatural amino acids. Proteins and methods of producing proteins with unnatural amino acids in eukaryotic cells are also provided.

  10. Unnatural reactive amino acid genetic code additions

    SciTech Connect

    Deiters, Alexander; Cropp, T. Ashton; Chin, Jason W.; Anderson, J. Christopher; Schultz, Peter G.

    2014-08-26

    This invention provides compositions and methods for producing translational components that expand the number of genetically encoded amino acids in eukaryotic cells. The components include orthogonal tRNAs, orthogonal aminoacyl-tRNA synthetases, orthogonal pairs of tRNAs/synthetases and unnatural amino acids. Proteins and methods of producing proteins with unnatural amino acids in eukaryotic cells are also provided.

  11. Unnatural reactive amino acid genetic code additions

    SciTech Connect

    Deiters, Alexander; Cropp, T. Ashton; Chin, Jason W.; Anderson, J. Christopher; Schultz, Peter G.

    2011-02-15

    This invention provides compositions and methods for producing translational components that expand the number of genetically encoded amino acids in eukaryotic cells. The components include orthogonal tRNAs, orthogonal aminoacyl-tRNA synthetases, orthogonal pairs of tRNAs/synthetases and unnatural amino acids. Proteins and methods of producing proteins with unnatural amino acids in eukaryotic cells are also provided.

  12. DFT computation and experimental analysis of vibrational and electronic spectra of phenoxy acetic acid herbicides

    NASA Astrophysics Data System (ADS)

    Arul Dhas, D.; Hubert Joe, I.; Roy, S. D. D.; Balachandran, S.

    2013-05-01

    An absolute vibrational analysis has been attempted on the basis of experimental FTIR and NIR-FT Raman spectra with calculated vibrational wavenumbers and intensities of phenoxy acetic acids. The equilibrium geometry, bonding features and harmonic vibrational wavenumbers have been calculated with the help of B3LYP method with Dunning correlation consistent basis set aug-cc-pVTZ. The electronic structures of molecular fragments were described in terms of natural bond orbital analysis, which shows intermolecular Osbnd H⋯O and intramolecular Csbnd H⋯O hydrogen bonds. The electronic absorption spectra with different solvents have been investigated in combination with time-dependent density functional theory calculation. The pKa values of phenoxy acetic acids were compared.

  13. Study of acetic acid production by immobilized acetobacter cells: oxygen transfer

    SciTech Connect

    Ghommidh, C.; Navarro, J.M.; Durand, G.

    1982-03-01

    The immobilization of living Acetobacter cells by adsorption onto a large-surface-area ceramic support was studied in a pulsed flow reactor. The high oxygen transfer capability of the reactor enabled acetic acid production rates up to 10.4 g/L/h to be achieved. Using a simple mathematical model incorporating both internal and external mass transfer coefficients, it was shown that oxygen transfer in the microbial film controls the reactor productivity. (Refs. 10).

  14. Identification of Indole-3-Acetic Acid in the Basidiomycete Schizophyllum commune 1

    PubMed Central

    Epstein, Ephraim; Miles, Philip G.

    1967-01-01

    Indole-3-acetic acid (IAA) was detected in the ether extracts of culture filtrates of indigotin-producing strains of the basidiomycete Schizophyllum commune. Several solvents, known to give distinctly different RF values for IAA, and 3 location reagents gave identical results with synthetic IAA and IAA found in the extract. Confirmation was obtained by the Avena straight growth test, split pea test, and ultraviolet absorption spectrum. PMID:16656596

  15. Adaptive laboratory evolution of ethanologenic Zymomonas mobilis strain tolerant to furfural and acetic acid inhibitors.

    PubMed

    Shui, Zong-Xia; Qin, Han; Wu, Bo; Ruan, Zhi-yong; Wang, Lu-shang; Tan, Fu-Rong; Wang, Jing-Li; Tang, Xiao-Yu; Dai, Li-Chun; Hu, Guo-Quan; He, Ming-Xiong

    2015-07-01

    Furfural and acetic acid from lignocellulosic hydrolysates are the prevalent inhibitors to Zymomonas mobilis during cellulosic ethanol production. Developing a strain tolerant to furfural or acetic acid inhibitors is difficul by using rational engineering strategies due to poor understanding of their underlying molecular mechanisms. In this study, strategy of adaptive laboratory evolution (ALE) was used for development of a furfural and acetic acid-tolerant strain. After three round evolution, four evolved mutants (ZMA7-2, ZMA7-3, ZMF3-2, and ZMF3-3) that showed higher growth capacity were successfully obtained via ALE method. Based on the results of profiling of cell growth, glucose utilization, ethanol yield, and activity of key enzymes, two desired strains, ZMA7-2 and ZMF3-3, were achieved, which showed higher tolerance under 7 g/l acetic acid and 3 g/l furfural stress condition. Especially, it is the first report of Z. mobilis strain that could tolerate higher furfural. The best strain, Z. mobilis ZMF3-3, has showed 94.84% theoretical ethanol yield under 3-g/l furfural stress condition, and the theoretical ethanol yield of ZM4 is only 9.89%. Our study also demonstrated that ALE method might also be used as a powerful metabolic engineering tool for metabolic engineering in Z. mobilis. Furthermore, the two best strains could be used as novel host for further metabolic engineering in cellulosic ethanol or future biorefinery. Importantly, the two strains may also be used as novel-tolerant model organisms for the genetic mechanism on the "omics" level, which will provide some useful information for inverse metabolic engineering. PMID:25935346

  16. Tipepidine enhances the antinociceptive-like action of carbamazepine in the acetic acid writhing test.

    PubMed

    Kawaura, Kazuaki; Miki, Risa; Urashima, Yuri; Honda, Sokichi; Shehata, Ahmed M; Soeda, Fumio; Shirasaki, Tetsuya; Takahama, Kazuo

    2011-01-25

    Several antidepressants have been used to treat severe pain in clinics. Recently, we reported that the centrally acting non-narcotic antitussive (cough suppressant drug), tipepidine produces an antidepressant-like effect in the forced swimming test, although the mechanism of action appears to be quite different from that of known antidepressants. In the present study, we investigated whether a combination of tipepidine and carbamazepine acts synergistically to induce an antinociceptive effect in the acetic acid-induced writhing test in mice. Prior to studying the combination of tipepidine and carbamazepine, the analgesic action of tipepidine alone was also examined in mice. Tipepidine at 5-40mg/kg i.p. significantly reduced the number of writhes induced by acetic acid in mice. Carbamazepine at 20mg/kg i.p. also significantly reduced the writhing reaction. Furthermore, co-administration of carbamazepine (5 and 10mg/kg, i.p.) and tipepidine (2.5mg/kg i.p.) significantly decreased the number of writhes induced by acetic acid. This finding suggests that a combination of carbamazepine and tipepidine may be a new strategy for the treatment of neuropathic pain such as what occurs in trigeminal neuralgia, because the use of carbamazepine is often limited by its adverse effects and by reduction of its analgesic efficacy by microsomal enzyme induction. PMID:21114989

  17. Corrosion resistance of aluminum-magnesium alloys in glacial acetic acid

    SciTech Connect

    Zaitseva, L.V.; Romaniv, V.I.

    1984-05-01

    Vessels for the storage and conveyance of glacial acetic acid are produced from ADO and AD1 aluminum, which are distinguished by corrosion resistance, weldability and workability in the hot and cold conditions but have low tensile strength. Aluminum-magnesium alloys are stronger materials close in corrosion resistance to technical purity aluminum. An investigation was made of the basic alloying components on the corrosion resistance of these alloys in glacial acetic acid. Both the base metal and the weld joints were tested. With an increase in temperature the corrosion rate of all of the tested materials increases by tens of times. The metals with higher magnesium content show more pitting damage. The relationship of the corrosion resistance of the alloys to magnesium content is confirmed by the similar intensity of failure of the joint metal of all of the investigated alloys and by electrochemical investigations. The data shows that AMg3 alloy is close to technically pure ADO aluminum. However, the susceptibility of even this material to local corrosion eliminates the possibility of the use of aluminum-magnesium alloys as reliable constructional materials in glacial acetic acid.

  18. Dual Antiplatelet Regime Versus Acetyl-acetic Acid for Carotid Artery Stenting

    SciTech Connect

    Dalainas, Ilias Nano, Giovanni; Bianchi, Paolo; Stegher, Silvia; Malacrida, Giovanni; Tealdi, Domenico G.

    2006-08-15

    Carotid artery stenting has been proposed as an option treatment of carotid artery stenosis. The aim of this single-institution study is to compare the dual-antiplatelet treatment and heparin combined with acetyl-acetic acid, in patients who underwent carotid artery stenting. We compared 2 groups of 50 patents each who underwent carotid artery stenting for primary atherosclerotic disease. Group A received heparin for 24 h combined with 325 mg acetyl-acetic acid and group B received 250 mg ticlopidine twice a day combined with 325 mg acetyl-acetic acid. Outcome measurements included 30-day bleeding and neurological complications and 30-day thrombosis/occlusion rates. The neurological complications were 16% in group A and 2% in group B (p < 0.05). Bleeding complications occurred in 4% in group A and 2% in group B (p > 0.05). The 30-day thrombosis/occlusion rate was 2% in group A and 0% in group B (p > 0.05). Dual antiplatelet treatment is recommended in all patients undergoing carotid artery stenting.

  19. A new medium containing mupirocin, acetic acid, and norfloxacin for the selective cultivation of bifidobacteria.

    PubMed

    Vlková, Eva; Salmonová, Hana; Bunešová, Věra; Geigerová, Martina; Rada, Vojtěch; Musilová, Šárka

    2015-08-01

    Various culture media have been proposed for the isolation and selective enumeration of bifidobacteria. Mupirocin is widely used as a selective factor along with glacial acetic acid. TOS (transgalactosylated oligosaccharides) medium supplemented with mupirocin is recommended by the International Dairy Federation for the detection of bifidobacteria in fermented milk products. Mupirocin media with acetic acid are also reliable for intestinal samples in which bifidobacteria predominate. However, for complex samples containing more diverse microbiota, the selectivity of mupirocin media is limited. Resistance to mupirocin has been demonstrated by many anaerobic bacteria, especially clostridia. The objective was to identify an antibiotic that inhibits the growth of clostridia and allows the growth of bifidobacteria, and to use the identified substance to develop a selective cultivation medium for bifidobacteria. The susceptibility of bifidobacteria and clostridia to 12 antibiotics was tested on agar using the disk diffusion method. Only norfloxacin inhibited the growth of clostridia and did not affect the growth of bifidobacteria. Using both pure cultures and faecal samples from infants, adults, calves, lambs, and piglets, the optimal concentration of norfloxacin in solid cultivation media was determined to be 200 mg/L. Our results showed that solid medium containing norfloxacin (200 mg/L) in combination with mupirocin (100 mg/L) and glacial acetic acid (1 mL/L) is suitable for the enumeration and isolation of bifidobacteria from faecal samples of different origins. PMID:25865525

  20. Reductions of aldehydes and ketones with a readily available N-heterocyclic carbene borane and acetic acid

    PubMed Central

    Lamm, Vladimir; Pan, Xiangcheng

    2013-01-01

    Summary Acetic acid promotes the reduction of aldehydes and ketones by the readily available N-heterocyclic carbene borane, 1,3-dimethylimidazol-2-ylidene borane. Aldehydes are reduced over 1–24 h at room temperature with 1 equiv of acetic acid and 0.5 equiv of the NHC-borane. Ketone reductions are slower but can be accelerated by using 5 equiv of acetic acid. Aldehydes can be selectively reduced in the presence of ketones. On a small scale, products are isolated by evaporation of the reaction mixture and direct chromatography. PMID:23616812

  1. Liquid structure of acetic acid-water and trifluoroacetic acid-water mixtures studied by large-angle X-ray scattering and NMR.

    PubMed

    Takamuku, Toshiyuki; Kyoshoin, Yasuhiro; Noguchi, Hiroshi; Kusano, Shoji; Yamaguchi, Toshio

    2007-08-01

    The structures of acetic acid (AA), trifluoroacetic acid (TFA), and their aqueous mixtures over the entire range of acid mole fraction xA have been investigated by using large-angle X-ray scattering (LAXS) and NMR techniques. The results from the LAXS experiments have shown that acetic acid molecules mainly form a chain structure via hydrogen bonding in the pure liquid. In acetic acid-water mixtures hydrogen bonds of acetic acid-water and water-water gradually increase with decreasing xA, while the chain structure of acetic acid molecules is moderately ruptured. Hydrogen bonds among water molecules are remarkably formed in acetic acid-water mixtures at xAacetic acid and TFA molecules for acetic acid-water and TFA-water mixtures have indicated strong relationships between a structural change of the mixtures and the acid mole fraction. On the basis of both LAXS and NMR results, the structural changes of acetic acid-water and TFA-water mixtures with decreasing acid mole fraction and the effects of fluorination of the methyl group on the structure are discussed at the molecular level. PMID:17628099

  2. [Selenazoles. XII. (1) Reaction of 4-(p-tolyl)-selenosemi-carbazides of acetic, benzoic, isonicotinic, nicotinic and picolinic acid with omega-acetophenone].

    PubMed

    Biliński, S; Bielak, L; Chmielewski, J; Marcewicz-Rojewska, B; Musik, I

    1989-01-01

    The cyclization of 4-(p-tolyl)-selenosemicarbazides of acetic, benzoic, isonicotinic, nicotinic and picolinic acids (Ia-e) with omega-bromoacetophenone was investigated in the medium of methanol (Method A) or in methanol in the presence of anhydrous sodium acetate (Method B). Acid hydrolysis of compounds IIf-i and IVa-c, e was studied. Results of UV and IR spectrometric measurements and of the in vitro microbiological studies are presented. In contradistinction to corresponding thiosemicarbazides, the change in N4 nitrogen atom basicity of the parent selenosemicarbazide I (pKa of p-toluidine = 5.1), in comparison to that of 4-phenyl-selenosemicarbazide (pKa of aniline = 4.63), proved to influence the equilibrium of the reaction with omega-bromoacetophenone only in the methanol medium without addition of anhydrous sodium acetate (Method A). PMID:2517572

  3. Characterization of acetic acid bacteria in traditional acetic acid fermentation of rice vinegar (komesu) and unpolished rice vinegar (kurosu) produced in Japan.

    PubMed

    Nanda, K; Taniguchi, M; Ujike, S; Ishihara, N; Mori, H; Ono, H; Murooka, Y

    2001-02-01

    Bacterial strains were isolated from samples of Japanese rice vinegar (komesu) and unpolished rice vinegar (kurosu) fermented by the traditional static method. Fermentations have never been inoculated with a pure culture since they were started in 1907. A total of 178 isolates were divided into groups A and B on the basis of enterobacterial repetitive intergenic consensus-PCR and random amplified polymorphic DNA fingerprinting analyses. The 16S ribosomal DNA sequences of strains belonging to each group showed similarities of more than 99% with Acetobacter pasteurianus. Group A strains overwhelmingly dominated all stages of fermentation of both types of vinegar. Our results indicate that appropriate strains of acetic acid bacteria have spontaneously established almost pure cultures during nearly a century of komesu and kurosu fermentation. PMID:11157275

  4. The role of cholinergic anti-inflammatory pathway in acetic acid-induced colonic inflammation in the rat.

    PubMed

    Kolgazi, Meltem; Uslu, Unal; Yuksel, Meral; Velioglu-Ogunc, Ayliz; Ercan, Feriha; Alican, Inci

    2013-09-01

    The "cholinergic anti-inflammatory pathway" provides neurological modulation of cytokine synthesis to limit the magnitude of the immune response. This study aimed to evaluate the impact of the cholinergic anti-inflammatory pathway on the extent of tissue integrity, oxidant-antioxidant status and neutrophil infiltration to the inflamed organ in a rat model of acetic acid-induced colitis. Colitis was induced by intrarectal administration of 5% acetic acid (1ml) to Sprague-Dawley rats (200-250g; n=7-8 per group). Control group received an equal volume of saline intrarectally. The rats were treated with either nicotine (1mg/kg/day) or huperzine A (0.1mg/kg/day) intraperitoneally for 3 days. After decapitation, the distal colon was scored macroscopically and microscopically. Tissue samples were used for the measurement of malondialdehyde (MDA) and glutathione (GSH) levels, and myeloperoxidase (MPO) activity. Formation of reactive oxygen species was monitored by using chemiluminescence (CL). Nuclear factor (NF)-κB expression was evaluated in colonic samples via immunohistochemical analysis. Trunk blood was collected for the assessment of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-10, resistin and visfatin levels. Both nicotine and huperzine A reduced the extent of colonic lesions, increased colonic MDA level, high MPO activity and NF-κB expression in the colitis group. Elevation of serum IL-1β level due to colitis was also attenuated by both treatments. Additionally, huperzine A was effective to reverse colitis-induced high lucigenin-enhanced CL values and serum TNF-α levels. Colitis group revealed decreased serum visfatin levels compared to control group which was completely reversed by nicotine. In conclusion, modulation of the cholinergic system either by nicotine or ACh esterase inhibition improved acetic acid-induced colonic inflammation as confirmed by macroscopic and microscopic examination and biochemical assays. PMID:23810507

  5. Synthesis of Saturated Long Chain Fatty Acids from Sodium Acetate-1-C14 by Mycoplasma1

    PubMed Central

    Pollack, J. D.; Tourtellotte, M. E.

    1967-01-01

    Three strains of Mycoplasma, M. laidlawii A and B, and Mycoplasma sp. A60549, were grown in broth containing sodium acetate-1-C14. The methyl esters of the phospholipid fatty acids of harvested radioactive cells were prepared and identified by comparison of their mobilities to known radioactive fatty acid methyl esters by use of a modified reversed-phase partition-thin layer chromatographic technique. No radioactive methyl oleate or methyl linoleate was detected. Compounds migrating as radioactive methyl myristate, stearate, palmitate, and, with less certainty, laurate and octanoate were detected. The qualitative findings for all three organisms appeared similar. M. laidlawii B synthesized a radioactive substance, presumably a saturated fatty acid detected as the methyl ester derivative, which migrated in a position intermediate to methyl myristate-1-C14 and methyl palmitate-1-C14. This work indicates that M. laidlawii A and B and Mycoplasma sp. A60549 are capable, in a complex medium containing fatty acids, of synthesizing saturated but not unsaturated fatty acids entirely or in part from acetate. Images PMID:6020566

  6. Effects of trimetazidine in ethanol- and acetic acid-induced colitis: oxidant/anti-oxidant status.

    PubMed

    Girgin; Karaoglu; Tüzün; Erkus; Ozütemiz; Dinçer; Batur; Tanyalçin

    1999-11-01

    There is overwhelming evidence in favour of a significant role of reactive oxygen metabolites (ROM) in the pathophysiology of inflammatory bowel disease (IBD) in man and in experimental animal models. This study was undertaken to investigate the possible protective effects of pretreatment with trimetazidine (TMZ) on the oxidant-anti-oxidant balance in ethanol- and acetic acid-induced colonic damage in rats. TMZ was chosen because of its various cytoprotective features (preserving cellular ATP levels, limiting intracellular acidosis and limiting inorganic phosphate, Na(+) and Ca(2+) accumulation) and anti-oxy characteristics which were previously reported. A total of 80 rats were randomized into eight major groups each consisting of 10 animals. Animals in groups 1, 2 and 3 served as models of ethanol-induced colitis (0.25 ml of 30% (v/v) ethanol), while group 4 served as their control. Animals in groups 5, 6 and 7 served as models of acetic acid-induced colitis (1 ml of 4% (v/v) acetic acid), while group 8 served as their control. TMZ was administered 5 mg/kg by intrarectal (i.r.) and intraperitoneal (i.p.) routes to groups 1, 2, 5 and 6. Intraperitoneal administration of TMZ was used in order to evaluate its systemic effect while i.r. administration was used to determine its local effect. After decapitation, colon mucosa samples were obtained and evaluated macroscopically and microscopically. Myeloperoxidase (MPO) activities as markers for inflammation, malondialdehyde (MDA) levels as markers for oxidant stress and reduced glutathione (GSH) and oxidized glutathione (GSSG) levels as markers for anti-oxidant status were determined. Acute colitis was observed in macroscopic and microscopic evaluation in ethanol- and acetic acid-administered groups compared with controls (P = 0.000). The macroscopic and microscopic scores in colitis groups were correlated with MPO activities (r = 0.5365, P = 0.000 and r = 0.5499, P = 0.000, respectively). MDA

  7. High Acetic Acid Production Rate Obtained by Microbial Electrosynthesis from Carbon Dioxide.

    PubMed

    Jourdin, Ludovic; Grieger, Timothy; Monetti, Juliette; Flexer, Victoria; Freguia, Stefano; Lu, Yang; Chen, Jun; Romano, Mark; Wallace, Gordon G; Keller, Jurg

    2015-11-17

    High product specificity and production rate are regarded as key success parameters for large-scale applicability of a (bio)chemical reaction technology. Here, we report a significant performance enhancement in acetate formation from CO2, reaching comparable productivity levels as in industrial fermentation processes (volumetric production rate and product yield). A biocathode current density of -102 ± 1 A m(-2) and an acetic acid production rate of 685 ± 30 (g m(-2) day(-1)) have been achieved in this study. High recoveries of 94 ± 2% of the CO2 supplied as the sole carbon source and 100 ± 4% of electrons into the final product (acetic acid) were achieved after development of a mature biofilm, reaching an elevated product titer of up to 11 g L(-1). This high product specificity is remarkable for mixed microbial cultures, which would make the product downstream processing easier and the technology more attractive. This performance enhancement was enabled through the combination of a well-acclimatized and enriched microbial culture (very fast start-up after culture transfer), coupled with the use of a newly synthesized electrode material, EPD-3D. The throwing power of the electrophoretic deposition technique, a method suitable for large-scale production, was harnessed to form multiwalled carbon nanotube coatings onto reticulated vitreous carbon to generate a hierarchical porous structure. PMID:26484732

  8. The adsorption of acetic acid on clean and oxygen-covered Au/Pd(100) alloy surfaces

    NASA Astrophysics Data System (ADS)

    Li, Zhenjun; Tysoe, Wilfred T.

    2012-12-01

    The adsorption of acetic acid is studied on clean and oxygen-covered Au/Pd(100) alloys as a function of gold content by temperature-programmed desorption and reflection-absorption infrared spectroscopy. Au/Pd(100) forms ordered alloys such that, for gold coverages above ~ 0.5 monolayers, only isolated palladium atoms surrounded by gold nearest neighbors are present. Predominantly molecular acetic acid forms on Au/Pd(100) alloy surfaces for gold coverages greater than ~ 0.56 ML, and desorbs with an activation energy of ~ 59 kJ/mol. Heating this surface also forms some η1-acetate species which decompose to form CO and hydrogen. On alloy surfaces with palladium-palladium bridge sites, η1-acetate species initially form, but rapidly convert into η2-species. They thermally decompose to form CO and hydrogen, with a small portion rehydrogenating to form acetic acid between 280 and 321 K depending on gold coverage. The presence of oxygen on both Pd(100) and Au/Pd(100) alloys facilitates acetate dehydrogenation so that only η2-acetate species form on these surfaces. The presence of oxygen also serves to stabilize the acetate species.

  9. Anaerobic co-digestion of acetate-rich with lignin-rich wastewater and the effect of hydrotalcite addition.

    PubMed

    Rodriguez-Chiang, Lourdes; Llorca, Jordi; Dahl, Olli

    2016-10-01

    The methane potential and biodegradability of different ratios of acetate and lignin-rich effluents from a neutral sulfite semi-chemical (NSSC) pulp mill were investigated. Results showed ultimate methane yields up to 333±5mLCH4/gCOD when only acetate-rich substrate was added and subsequently lower methane potentials of 192±4mLCH4/gCOD when the lignin fraction was increased. The presence of lignin showed a linear decay in methane production, resulting in a 41% decrease in methane when the lignin-rich feed had a 30% increase. A negative linear correlation between lignin content and biodegradability was also observed. Furthermore, the effect of hydrotalcite (HT) addition was evaluated and showed increase in methane potential of up to 8%, a faster production rate and higher soluble lignin removal (7-12% higher). Chemical oxygen demand (COD) removal efficiencies between 64 and 83% were obtained for all samples. PMID:27347802

  10. Sources and sinks of formic, acetic, and pyruvic acids over central Amazonia. II - Wet season

    NASA Technical Reports Server (NTRS)

    Talbot, R. W.; Andreae, M. O.; Berresheim, H.; Jacob, D. J.; Beecher, K. M.

    1990-01-01

    Potential sources and sinks of formic, acetic, and pyruvic acids over the Amazon forest were investigated using a photochemical model and data collected on gas phase concentrations of these acids in the forest canopy, boundary layer, and free troposphere over the central Amazon Basin during the 1987 wet season. It was found that the atmospheric reactions previously suggested in the literature as sources of carboxylic acids (i.e., the gas phase decomposition of isoprene, the reaction between CH3CO3 and a peroxide, and aqueous phase oxidation of CH2O) appear to be too slow to explain the observed concentrations, suggesting that other atmospheric reactions, so far unidentified, could make a major contribution to the carboxylic acid budgets.

  11. Microemulsion liquid membranes. I. Application to acetic acid removal from water

    SciTech Connect

    Wiencek, J.M.; Qutubuddin, S. )

    1992-08-01

    A separation technique utilizing nonionic microemulsions as emulsion liquid membranes has been successfully applied to the removal of acetic acid from an aqueous feed phase. The surfactant systems were carefully characterized in order to assure that they were truly microemulsions. The effects of mixing intensity, feed concentration, treat ratio, and microemulsion viscosity on the separation kinetics were investigated. The microemulsions did not typically display leakage and had negligible swell over 5-minute duration. The reversible phase behavior of the microemulsion was utilized to demulsify the liquid membrane phase and recover the acetate ion via a temperature change of approximately 40 C. Material balances closed to within 10% and rates of separation were faster than the sampling rates when the microemulsion was fully dispersed in the aqueous feed phase.

  12. Preparation of a novel colorimetric luminescence sensor strip for the detection of indole-3-acetic acid.

    PubMed

    Liu, Yan; Dong, Haitao; Zhang, Wenzhu; Ye, Zhiqiang; Wang, Guilan; Yuan, Jingli

    2010-06-15

    A novel colorimetric luminescence sensor strip for the detection of indole-3-acetic acid (IAA) has been fabricated by using green emissive quantum dots of cadmium telluride (CdTe QDs) as a background layer and a red emissive europium chelate, [4'-(9-anthryl)-2,2':6',2''-terpyridine-6,6''-diyl]bis(methylenenitrilo) tetrakis(acetate)-Eu(3+) (ATTA-Eu(3+)), as a specific sensing layer coated on the surface of glass slide, respectively. The luminescence response of the sensor strip is given by the dramatic changes in emission colors from green to red at different IAA concentrations. This approach provides a simple, rapid, sensitive and accurate method for the detection of IAA without using any special scientific instruments. PMID:20353890

  13. Mediated electrochemical measurement of the inhibitory effects of furfural and acetic acid on Saccharomyces cerevisiae and Candida shehatae.

    PubMed

    Zhao, Jinsheng; Wang, Min; Yang, Zhenyu; Gong, Qintao; Lu, Yao; Yang, Zhengyu

    2005-02-01

    The toxic effects of furfural and acetic acid on two yeasts, Saccharomyces cerevisiae and Candida shehatae, were evaluated using an electrochemical method. Intracellular redox activities were lowered by 40% and 78% for S. cerevisiae and C. shehatae, respectively, by 8 g furfural l(-1), and by 46% and 67%, respectively, by 8 g acetic acid l(-1). The proposed method can accurately measure the effects of inhibitors on cell cultures. PMID:15717131

  14. Inhibition of Methanogenesis from Acetate in Granular Sludge by Long-Chain Fatty Acids

    PubMed Central

    Koster, Iman W.; Cramer, Albertus

    1987-01-01

    The effect of four saturated long-chain fatty acids (caprylic, capric, lauric, and myristic) and one unsaturated long-chain fatty acid (oleic) on the microbial formation of methane from acetate was investigated in batch anaerobic toxicity assays. The tests were carried out with granular sludge from an upflow anaerobic sludge bed reactor. In this sludge, Methanothrix spp. are the predominant acetoclastic methanogens. Lauric acid appeared to be the most versatile inhibitor: inhibition started at 1.6 mM, and at 4.3 mM the maximum specific acetoclastic methanogenic activity had been reduced to 50%. Caprylic acid appeared to be only slightly inhibitory. Oleic acid was almost as inhibitory as lauric acid. Although adsorption of the inhibitor on the cell wall might play an important role in the mechanism of inhibition, the inhibition was found to be correlated with concentration rather than with the amount per unit of biomass. In practical situations, as in anaerobic waste treatment processes, synergism can be expected to enhance the inhibition of methanogenesis. In the present research a background concentration of lauric acid below its MIC strongly enhanced the toxicity of capric acid and (to an even greater extent) myristic acid. PMID:16347288

  15. Acetic Acid Bacterial Biota of the Pink Sugar Cane Mealybug, Saccharococcus sacchari, and Its Environs

    PubMed Central

    Ashbolt, Nicholas J.; Inkerman, Peter A.

    1990-01-01

    Saccharococcus sacchari is the primary colonizer of the developing “sterile” tissue between the leaf sheath and stem of sugar cane. The honeydew secreted by the mealybugs is acidic (about pH 3) and supports an atypical epiphytic microbiota dominated by acetobacter-like bacteria and acidophilic yeast species. However, Erwinia and Leuconostoc species predominate within the leaf sheath pocket region when the mealybugs die out. The unidentified acetobacters were readily isolated from S. sacchari throughout its life cycle and from other genera of mealybugs on sugar cane and various other plants, both above and below ground. No other insect present on sugar cane was a significant vector of acetic acid bacteria. The major factors restricting microbial diversity within the environs of mealybugs were considered to be yeast activity along with bacterial production of acetic acid, ketogluconic acids, and gamma-pyrones, in association with their lowering of pH. The microbial products may aid in suppressing the attack by the parasitic mold Aspergillus parasiticus on mealybugs but could act as attractants for the predatory fruit fly Cacoxenus perspicax. PMID:16348144

  16. A mutation affecting the synthesis of 4-chloroindole-3-acetic acid.

    PubMed

    Ross, John J; Tivendale, Nathan D; Davidson, Sandra E; Reid, James B; Davies, Noel W; Quittenden, Laura J; Smith, Jason A

    2012-12-01

    Traditionally, schemes depicting auxin biosynthesis in plants have been notoriously complex. They have involved up to four possible pathways by which the amino acid tryptophan might be converted to the main active auxin, indole-3-acetic acid (IAA), while another pathway was suggested to bypass tryptophan altogether. It was also postulated that different plants use different pathways, further adding to the complexity. In 2011, however, it was suggested that one of the four tryptophan-dependent pathways, via indole-3-pyruvic acid (IPyA), is the main pathway in Arabidopsis thaliana, although concurrent operation of one or more other pathways has not been excluded. We recently showed that, for seeds of Pisum sativum (pea), it is possible to go one step further. Our new evidence indicates that the IPyA pathway is the only tryptophan-dependent IAA synthesis pathway operating in pea seeds. We also demonstrated that the main auxin in developing pea seeds, 4-chloroindole-3-acetic acid (4-Cl-IAA), which accumulates to levels far exceeding those of IAA, is synthesized via a chlorinated version of the IPyA pathway. PMID:23073010

  17. Indole-3-acetic acid protein conjugates: novel players in auxin homeostasis.

    PubMed

    Seidel, C; Walz, A; Park, S; Cohen, J D; Ludwig-Müller, J

    2006-05-01

    Indole-3-acetic acid (IAA) is found in plants in both free and conjugated forms. Within the group of conjugated IAA there is a unique class of proteins and peptides where IAA is attached directly to the polypeptide structure as a prosthetic group. The first gene, IAP1, encoding for a protein with IAA as a prosthetic group, was cloned from bean (Phaseolus vulgaris). It was shown that the expression of IAP1 as a major IAA modified protein in bean seed (PvIAP1) was correlated to a developmental period of rapid growth during seed development. Moreover, this protein underwent rapid degradation during germination. Since further molecular analysis was difficult in bean, the IAP1 gene was transformed into Arabidopsis thaliana and Medicago truncatula. Expression of the bean IAP1 gene in both plant species under the control of its native promoter targeted protein expression to the seeds. In Arabidopsis no IAA was found to be attached to PvIAP1. These results show that there is specificity to protein modification by IAA and suggests that protein conjugation may be catalyzed by species specific enzymes. Furthermore, subcellular localization showed that in Arabidopsis PvIAP1 was predominantly associated with the microsomal fraction. In addition, a related protein and several smaller peptides that are conjugated to IAA were identified in Arabidopsis. Further research on this novel class of proteins from Arabidopsis will both advance our knowledge of IAA proteins and explore aspects of auxin homeostasis that were not fully revealed by studies of free IAA and lower molecular weight conjugates. PMID:16807826

  18. Global effect of indole-3-acetic acid biosynthesis on multiple virulence factors of Erwinia chrysanthemi 3937.

    PubMed

    Yang, Shihui; Zhang, Qiu; Guo, Jianhua; Charkowski, Amy O; Glick, Bernard R; Ibekwe, A Mark; Cooksey, Donald A; Yang, Ching-Hong

    2007-02-01

    Production of the plant hormone indole-3-acetic acid (IAA) is widespread among plant-associated microorganisms. The non-gall-forming phytopathogen Erwinia chrysanthemi 3937 (strain Ech3937) possesses iaaM (ASAP16562) and iaaH (ASAP16563) gene homologues. In this work, the null knockout iaaM mutant strain Ech138 was constructed. The IAA production by Ech138 was reduced in M9 minimal medium supplemented with l-tryptophan. Compared with wild-type Ech3937, Ech138 exhibited reduced ability to produce local maceration, but its multiplication in Saintpaulia ionantha was unaffected. The pectate lyase production of Ech138 was diminished. Compared with wild-type Ech3937, the expression levels of an oligogalacturonate lyase gene, ogl, and three endopectate lyase genes, pelD, pelI, and pelL, were reduced in Ech138 as determined by a green fluorescent protein-based fluorescence-activated cell sorting promoter activity assay. In addition, the transcription of type III secretion system (T3SS) genes, dspE (a putative T3SS effector) and hrpN (T3SS harpin), was found to be diminished in the iaaM mutant Ech138. Compared with Ech3937, reduced expression of hrpL (a T3SS alternative sigma factor) and gacA but increased expression of rsmA in Ech138 was also observed, suggesting that the regulation of T3SS and pectate lyase genes by IAA biosynthesis might be partially due to the posttranscriptional regulation of the Gac-Rsm regulatory pathway. PMID:17189441

  19. Production of bio-oil rich in acetic acid and phenol from fast pyrolysis of palm residues using a fluidized bed reactor: Influence of activated carbons.

    PubMed

    Jeong, Jae-Yong; Lee, Uen-Do; Chang, Won-Seok; Jeong, Soo-Hwa

    2016-11-01

    In this study, palm residues were pyrolyzed in a bench-scale (3kg/h) fast pyrolysis plant equipped with a fluidized bed reactor and bio-oil separation system for the production of bio-oil rich in acetic acid and phenol. Pyrolysis experiments were performed to investigate the effects of reaction temperature and the types and amounts of activated carbon on the bio-oil composition. The maximum bio-oil yield obtained was approximately 47wt% at a reaction temperature of 515°C. The main compounds produced from the bio-oils were acetic acid, hydroxyacetone, phenol, and phenolic compounds such as cresol, xylenol, and pyrocatechol. When coal-derived activated carbon was applied, the acetic acid and phenol yields in the bio-oils reached 21 and 19wt%, respectively. Finally, bio-oils rich in acetic acid and phenol could be produced separately by using an in situ bio-oil separation system and activated carbon as an additive. PMID:27501032

  20. Silver nanoparticles in combination with acetic acid and zinc oxide quantum dots for antibacterial activities improvement-A comparative study

    NASA Astrophysics Data System (ADS)

    Sedira, Sofiane; Ayachi, Ahmed Abdelhakim; Lakehal, Sihem; Fateh, Merouane; Achour, Slimane

    2014-08-01

    Due to their remarkable antibacterial/antivirus properties, silver nanoparticles (Ag NPs) and zinc oxide quantum dots (ZnO Qds) have been widely used in the antimicrobial field. The mechanism of action of Ag NPs on bacteria was recently studied and it has been proven that Ag NPs exerts their antibacterial activities mainly by the released Ag+. In this work, Ag NPs and ZnO Qds were synthesized using polyol and hydrothermal method, respectively. It was demonstrated that Ag NPs can be oxidized easily in aqueous solution and the addition of acetic acid can increase the Ag+ release which improves the antibacterial activity of Ag NPs. A comparative study between bactericidal effect of Ag NPs/acetic acid and Ag NPs/ZnO Qds on Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumonia and Staphylococcus aureus was undertaken using agar diffusion method. The obtained colloids were characterized using UV-vis spectroscopy, Raman spectrometry, X-ray diffraction (XRD), transmission electron microscopy (TEM) and atomic force microscopy (AFM).

  1. Comparison and evaluation of analysis procedures for the quantification of (2-methoxyethoxy)acetic acid in urine.

    PubMed

    B'Hymer, Clayton; Butler, Mary Ann; Cheever, Kenneth L

    2005-09-01

    Several extraction and derivatization procedures were evaluated for the quantification of (2-methoxyethoxy)acetic acid (MEAA) in urine. MEAA is a metabolite and a biomarker for exposure to 2-(2-methoxyethoxy)ethanol, a glycol ether with widespread use in various industrial applications and the specific use as an anti-icing additive in the military jet fuel formulation JP-8. Quantification of glycol ether biomarkers is an active area of analytical research. Various sample preparation procedures were evaluated: liquid-liquid extraction (LLE) using ethyl acetate yielded the highest recovery, and solid-phase extraction (SPE) gave low recovery of MEAA. Two derivatization procedures were thoroughly investigated and validated, namely, silylation of MEAA with N-methyl-N-(tert-butyldimethylsilyl)trifluoroacetamide (MTBSTFA), and esterification of MEAA using ethanol. Quantification was performed by gas chromatography (GC) with a mass spectrometer as detector and using a polydimethylsiloxane (HP-1) capillary column. Deuterated 2-butoxyacetic acid (d-BAA) was used as an internal standard. Recovery studies of spiked human urine demonstrated the accuracy and precision of both procedures. The limit of detection (LOD) and other figures of merit for both derivatization procedures will be discussed in detail. Applications of these analysis procedures are also discussed. PMID:16158298

  2. Identification of acetic acid bacteria in traditionally produced vinegar and mother of vinegar by using different molecular techniques.

    PubMed

    Yetiman, Ahmet E; Kesmen, Zülal

    2015-07-01

    Culture-dependent and culture-independent methods were combined for the investigation of acetic acid bacteria (AAB) populations in traditionally produced vinegars and mother of vinegar samples obtained from apple and grape. The culture-independent denaturing gradient gel electrophoresis (DGGE) analysis, which targeted the V7-V8 regions of the 16S rRNA gene, showed that Komagataeibacter hansenii and Komagataeibacter europaeus/Komagataeibacter xylinus were the most dominant species in almost all of the samples analyzed directly. The culture-independent GTG5-rep PCR fingerprinting was used in the preliminary characterization of AAB isolates and species-level identification was carried out by sequencing of the 16S rRNA gene, 16S-23S rDNA internally transcribed to the spacer (ITS) region and tuf gene. Acetobacter okinawensis was frequently isolated from samples obtained from apple while K. europaeus was identified as the dominant species, followed by Acetobacter indonesiensis in the samples originating from grape. In addition to common molecular techniques, real-time PCR intercalating dye assays, including DNA melting temperature (Tm) and high resolution melting analysis (HRM), were applied to acetic acid bacterial isolates for the first time. The target sequence of ITS region generated species-specific HRM profiles and Tm values allowed discrimination at species level. PMID:25828705

  3. Impact of gluconic fermentation of strawberry using acetic acid bacteria on amino acids and biogenic amines profile.

    PubMed

    Ordóñez, J L; Sainz, F; Callejón, R M; Troncoso, A M; Torija, M J; García-Parrilla, M C

    2015-07-01

    This paper studies the amino acid profile of beverages obtained through the fermentation of strawberry purée by a surface culture using three strains belonging to different acetic acid bacteria species (one of Gluconobacter japonicus, one of Gluconobacter oxydans and one of Acetobacter malorum). An HPLC-UV method involving diethyl ethoxymethylenemalonate (DEEMM) was adapted and validated. From the entire set of 21 amino acids, multiple linear regressions showed that glutamine, alanine, arginine, tryptophan, GABA and proline were significantly related to the fermentation process. Furthermore, linear discriminant analysis classified 100% of the samples correctly in accordance with the microorganism involved. G. japonicus consumed glucose most quickly and achieved the greatest decrease in amino acid concentration. None of the 8 biogenic amines were detected in the final products, which could serve as a safety guarantee for these strawberry gluconic fermentation beverages, in this regard. PMID:25704705

  4. Auxin Biosynthesis: Are the Indole-3-Acetic Acid and Phenylacetic Acid Biosynthesis Pathways Mirror Images?1[OPEN

    PubMed Central

    Nichols, David S.; Smith, Jason; Chourey, Prem S.; McAdam, Erin L.; Quittenden, Laura

    2016-01-01

    The biosynthesis of the main auxin in plants (indole-3-acetic acid [IAA]) has been elucidated recently and is thought to involve the sequential conversion of Trp to indole-3-pyruvic acid to IAA. However, the pathway leading to a less well studied auxin, phenylacetic acid (PAA), remains unclear. Here, we present evidence from metabolism experiments that PAA is synthesized from the amino acid Phe, via phenylpyruvate. In pea (Pisum sativum), the reverse reaction, phenylpyruvate to Phe, is also demonstrated. However, despite similarities between the pathways leading to IAA and PAA, evidence from mutants in pea and maize (Zea mays) indicate that IAA biosynthetic enzymes are not the main enzymes for PAA biosynthesis. Instead, we identified a putative aromatic aminotransferase (PsArAT) from pea that may function in the PAA synthesis pathway. PMID:27208245

  5. 40 CFR 721.2076 - D-Glucuronic acid, polymer with 6-deoxy-L-mannose and D-glucose, acetate, calcium magnesium...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-deoxy-L-mannose and D-glucose, acetate, calcium magnesium potassium sodium salt. 721.2076 Section 721...-Glucuronic acid, polymer with 6-deoxy-L-mannose and D-glucose, acetate, calcium magnesium potassium sodium... identified as D-Glucuronic acid, polymer with 6-deoxy-L-mannose and D-glucose, acetate, calcium...

  6. 40 CFR 721.2076 - D-Glucuronic acid, polymer with 6-deoxy-L-mannose and D-glucose, acetate, calcium magnesium...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-deoxy-L-mannose and D-glucose, acetate, calcium magnesium potassium sodium salt. 721.2076 Section 721...-Glucuronic acid, polymer with 6-deoxy-L-mannose and D-glucose, acetate, calcium magnesium potassium sodium... identified as D-Glucuronic acid, polymer with 6-deoxy-L-mannose and D-glucose, acetate, calcium...

  7. The Partitioning of Acetic, Formic, and Phosphoric Acids Between Liquid Water and Steam

    SciTech Connect

    Gruszkiewicz, M.S.; Marshall, S.L.; Palmer, D.A.; Simonson, J.M.

    1999-06-22

    The chemical carryover of impurities and treatment chemicals from the boiler to the steam phase, and ultimately to the low-pressure turbine and condenser, can be quantified based on laboratory experiments preformed over ranges of temperature, pH, and composition. The two major assumptions are that thermodynamic equilibrium is maintained and no deposition, adsorption or decomposition occurs. The most recent results on acetic, formic and phosphoric acids are presented with consideration of the effects of hydrolysis and dimerization reactions. Complications arising from thermal decomposition of the organic acids are discussed. The partitioning constants for these acids and other solutes measured in this program have been incorporated into a simple thermodynamic computer code that calculates the effect of chemical and mechanical carryover on the composition of the condensate formed to varying extents in the water/steam cycle.

  8. Glycolaldehyde, methyl formate and acetic acid adsorption and thermal desorption from interstellar ices

    NASA Astrophysics Data System (ADS)

    Burke, Daren J.; Puletti, Fabrizio; Brown, Wendy A.; Woods, Paul M.; Viti, Serena; Slater, Ben

    2015-02-01

    We have undertaken a detailed investigation of the adsorption, desorption and thermal processing of the astrobiologically significant isomers glycolaldehyde, acetic acid and methyl formate. Here, we present the results of laboratory infrared and temperature programmed desorption (TPD) studies of the three isomers from model interstellar ices adsorbed on a carbonaceous dust grain analogue surface. Laboratory infrared data show that the isomers can be clearly distinguished on the basis of their infrared spectra, which has implications for observations of interstellar ice spectra. Laboratory TPD data also show that the three isomers can be distinguished on the basis of their thermal desorption behaviour. In particular, TPD data show that the isomers cannot be treated the same way in astrophysical models of desorption. The desorption of glycolaldehyde and acetic acid from water-dominated ices is very similar, with desorption being mainly dictated by water ice. However, methyl formate also desorbs from the surface of the ice, as a pure desorption feature, and therefore desorbs at a lower temperature than the other two isomers. This is more clearly indicated by models of the desorption on astrophysical time-scales corresponding to the heating rate of 25 and 5 M⊙ stars. For a 25 M⊙ star, our model shows that a proportion of the methyl formate can be found in the gas phase at earlier times compared to glycolaldehyde and acetic acid. This has implications for the observation and detection of these molecules, and potentially explains why methyl formate has been observed in a wider range of astrophysical environments than the other two isomers.

  9. The role of methanogens in acetic acid production under different salinity conditions.

    PubMed

    Xiao, Keke; Guo, Chenghong; Maspolim, Yogananda; Zhou, Yan; Ng, Wun Jern

    2016-10-01

    In this study, a fed-batch acidogenic reactor was operated at a 3 d hydraulic retention time (HRT) and fed with alkaline pre-treated sludge to investigate salinity effects on methanogens' abundance, activities and their consumption of produced acetic acid (HAc) and total volatile fatty acids (VFAs). The salinity concentration was increased step-wise by adding sodium chloride. At 3‰ (parts per thousand) salinity, the average produced volatile fatty acids (VFAs) concentration was 2410.16 ± 637.62 mg COD L(-1) and 2.70 ± 0.36 L methane was produced daily in the acidogenic reactor. Further batch tests indicated methanogens showed a HAc degradation rate of 3.81 mg COD g(-1) VSS h(-1) at initial HAc concentration of 1150 mg COD L(-1), and showed tolerance up to 16‰ salinity (3.76 g Na(+) L(-1)) as indicated by a constant HAc degradation rate. The microbiological study indicated this can be related to the predominance of acetate-utilizing Methanosarcinaceae and Methanomicrobiales in the reactor. However, with salinity increased to 20‰ and 40‰, increases in VFAs and HAc production and decreases in methane production, methanogens population, acidogenic bacteria population and acidification extent were observed. This study demonstrated presence of acetate-utilizing methanogens in an acidogenic reactor and their high tolerance to salinity, as well as their negative impacts on net VFAs production. The results would suggest the presence of methanogens in the acidogenic reactor should not be ignored and the recovery of methane from the acidogenic reactor needs to be considered to avoid carbon loss. PMID:27421101

  10. Graft Loss Due to Percutaneous Sclerotherapy of a Lymphocele Using Acetic Acid After Renal Transplantation

    SciTech Connect

    Adani, Gian Luigi Baccarani, Umberto; Bresadola, Vittorio; Lorenzin, Dario; Montanaro, Domenico; Risaliti, Andrea; Terrosu, Giovanni; Sponza, Massimo; Bresadola, Fabrizio

    2005-12-15

    Development of lymphoceles after renal transplantation is a well-described complication that occurs in up to 40% of recipients. The gold standard approach for the treatment of symptomatic cases is not well defined yet. Management options include simple aspiration, marsupialization by a laparotomy or laparoscopy, and percutaneous sclerotherapy using different chemical agents. Those approaches can be associated, and they depend on type, dimension, and localization of the lymphocele. Percutaneous sclerotherapy is considered to be less invasive than the surgical approach; it can be used safely and effectively, with low morbidity, in huge, rapidly accumulating lymphoceles. Moreover, this approach is highly successful, and the complication rate is acceptable; the major drawback is a recurrence rate close to 20%. We herewith report a renal transplant case in which the patient developed a symptomatic lymphocele that was initially treated by ultrasound-guided percutaneous sclerotherapy with ethanol and thereafter using acetic acid for early recurrence. A few hours after injection of acetic acid in the lymphatic cavity, the patient started to complain of acute pain localized to the renal graft and fever. An ultrasound of the abdomen revealed thrombosis of the renal vein and artery. The patient was immediately taken to the operating room, where the diagnosis of vascular thrombosis was confirmed and the graft was urgently explanted. In conclusion, we strongly suggest avoiding the use of acetic acid as a slerosating agent for the percutaneous treatment of post-renal transplant lymphocele because, based on our experience, it could be complicated by vascular thrombosis of the kidney, ending in graft loss.

  11. Lipases and whole cell biotransformations of 2-hydroxy-2-(ethoxyphenylphosphinyl)acetic acid and its ester.

    PubMed

    Majewska, Paulina; Serafin, Monika; Klimek-Ochab, Magdalena; Brzezińska-Rodak, Małgorzata; Żymańczyk-Duda, Ewa

    2016-06-01

    A wide spectrum of commercially available lipases and microbial whole cells catalysts were tested for biotransformations of 2-hydroxy-2-(ethoxyphenylphosphinyl)acetic acid 1 and its butyryl ester. The best results were achieved for biocatalytic hydrolysis of ester: 2-butyryloxy-2-(ethoxyphenylphosphinyl)acetic acid 2 performed by lipase from Candida cylindracea, what gave optically active products with 85% enantiomeric excess, 50% conversion degree and enantioselectivity 32.9 for one pair of enantiomers. Also enzymatic systems of Penicillium minioluteum and Fusarium oxysporum were able to hydrolyze tested compound with high enantiomeric excess (68-93% ee), enantioselectivity (44 for one pair of enantiomers) and conversion degree about 50-55%. Enzymatic acylation of hydroxyphosphinate was successful in case when porcine pancreas lipase was used. After 4days of biotransformation the conversion reaches 45% but the enantiomeric enrichment of the isomers mixture do not exceed 43%. Obtained chiral compounds are valuable derivatizing agents for spectroscopic (NMR) evaluation of enantiomeric excess for particular compounds (e.g. amino acids). PMID:26989983

  12. Simultaneous determination of 2-naphthoxyacetic acid and indole-3-acetic acid by first derivation synchronous fluorescence spectroscopy.

    PubMed

    Liu, Xiangxiang; Wan, Yiqun

    2013-07-01

    A simple, rapid, sensitive and selective method for simultaneously determining 2-naphthoxyacetic acid (BNOA) and Indole-3-Acetic Acid (IAA) in mixtures has been developed using derivation synchronous fluorescence spectroscopy based on their synchronous fluorescence. The synchronous fluorescence spectra were obtained with Δλ=100 nm in a pH 8.5 NaH2PO4-NaOH buffer solution, and the detected wavelengths of quantitative analysis were set at 239 nm for BNOA and 293 nm for IAA respectively. The over lapped fluorescence spectra were well separated by the synchronous derivative method. Under optimized conditions, the limits of detection (LOD) were 0.003 μg/mL for BNOA and 0.012 μg/mL for IAA. This method is simple and expeditious, and it has been successfully applied to the determination of 2-naphthoxyacetic acid and indole-3-acetic acid in fruit juice samples with satisfactory results. The samples were only filtrated through a 0.45 μm membrane filter, which was free from the tedious separation procedures. The obtaining recoveries were in the range of 83.88-87.43% for BNOA and 80.76-86.68% for IAA, and the relative standard deviations were all less than 5.0%. Statistical comparison of the results with high performance liquid chromatography Mass Spectrometry (HPLC-MS) method revealed good agreement and proved that there were no significant difference in the accuracy and precision between these two methods. PMID:23651742

  13. Simultaneous determination of 2-naphthoxyacetic acid and indole-3-acetic acid by first derivation synchronous fluorescence spectroscopy

    NASA Astrophysics Data System (ADS)

    Liu, Xiangxiang; Wan, Yiqun

    2013-07-01

    A simple, rapid, sensitive and selective method for simultaneously determining 2-naphthoxyacetic acid (BNOA) and Indole-3-Acetic Acid (IAA) in mixtures has been developed using derivation synchronous fluorescence spectroscopy based on their synchronous fluorescence. The synchronous fluorescence spectra were obtained with Δλ = 100 nm in a pH 8.5 NaH2PO4-NaOH buffer solution, and the detected wavelengths of quantitative analysis were set at 239 nm for BNOA and 293 nm for IAA respectively. The over lapped fluorescence spectra were well separated by the synchronous derivative method. Under optimized conditions, the limits of detection (LOD) were 0.003 μg/mL for BNOA and 0.012 μg/mL for IAA. This method is simple and expeditious, and it has been successfully applied to the determination of 2-naphthoxyacetic acid and indole-3-acetic acid in fruit juice samples with satisfactory results. The samples were only filtrated through a 0.45 μm membrane filter, which was free from the tedious separation procedures. The obtaining recoveries were in the range of 83.88-87.43% for BNOA and 80.76-86.68% for IAA, and the relative standard deviations were all less than 5.0%. Statistical comparison of the results with high performance liquid chromatography Mass Spectrometry (HPLC-MS) method revealed good agreement and proved that there were no significant difference in the accuracy and precision between these two methods.

  14. Crystal structure of 3-acet-oxy-2-methyl-benzoic acid.

    PubMed

    Saranya, Matheswaran; Subashini, Annamalai; Arunagiri, Chidambaram; Muthiah, Packianathan Thomas

    2015-07-01

    In the title mol-ecule, C10H10O4, the carb-oxy-lic acid group is twisted by 11.37 (15)° from the plane of the benzene ring and the acet-oxy group is twisted from this plane by 86.60 (17)°. In the crystal, mol-ecules are linked by pairs of O-H⋯O hydrogen bonds, forming inversion dimers with the expected R 2 (2)(8) graph-set motif. PMID:26279915

  15. XAS and RIXS study of acetic acid and methyl formate in liquid

    NASA Astrophysics Data System (ADS)

    Takahashi, O.; Nishida, N.; Kanai, S.; Horikawa, Y.; Tokushima, T.

    2016-05-01

    Structure of acetic acid (AA) and methyl formate (MF) in the liquid phase is studied using X-ray absorption spectroscopy (XAS) and X-ray emission spectroscopy (XES) experimentally and theoretically. Two distinct XES spectra are observed by tuning photon energy for both molecules. Model structure in the liquid phase is constructed using the classical and first principle molecular dynamics simulations, and XES spectra are calculated using density functional theory. Calculated XES spectra are consistent with experimental ones. The effect of core-hole induced excited state molecular dynamics are discussed.

  16. Hydroxylamine hydrochloride-acetic acid-soluble and -insoluble fractions of pelagic sediment: Readsorption revisited

    USGS Publications Warehouse

    Piper, D.Z.; Wandless, G.A.

    1992-01-01

    The extraction of the rare earth elements (REE) from deep-ocean pelagic sediment, using hydroxylamine hydrochloride-acetic acid, leads to the separation of approximately 70% of the bulk REE content into the soluble fraction and 30% into the insoluble fraction. The REE pattern of the soluble fraction, i.e., the content of REE normalized to average shale on an element-by-element basis and plotted against atomic number, resembles the pattern for seawater, whereas the pattern, as well as the absolute concentrations, in the insoluble fraction resembles the North American shale composite. These results preclude significant readsorption of the REE by the insoluble phases during the leaching procedure.

  17. Benzimidazole as corrosion inhibitor for heat treated 6061 Al- SiCp composite in acetic acid

    NASA Astrophysics Data System (ADS)

    Chacko, Melby; Nayak, Jagannath

    2015-06-01

    6061 Al-SiCpcomposite was solutionizedat 350 °C for 30 minutes and water quenched. It was then underaged at 140 °C (T6 treatment). The aging behaviour of the composite was studied using Rockwell B hardness measurement. Corrosion behaviour of the underaged sample was studied in different concentrations of acetic acid and at different temperatures. Benzimidazole at different concentrations was used for the inhibition studies. Inhibition efficiency of benzimidazole was calculated for different experimental conditions. Thermodynamic parameters were found out which suggested benzimidazole is an efficient inhibitor and it adsorbed on to the surface of composite by mixed adsorption where chemisorption is predominant.

  18. Iron-control additives improve acidizing

    SciTech Connect

    Walker, M.; Dill, W. ); Besler, M. )

    1989-07-24

    Iron sulfide and sulfur precipitation in sour wells can be controlled with iron-sequestering agents and sulfide modifiers. Oil production has been routinely increased in sour wells where precipitation of iron sulfide and elemental sulfur has been brought under control. Production increases have been especially noteworthy on wells that had a history of rapid production decline after acid stimulation. Twenty-fold production increases have been recorded. Key to the production increase has been to increase permeability with: Iron chelating agents that control precipitation of iron sulfide. A sulfide modifier that reduces precipitation of solids in the presence of excessive amounts of hydrogen sulfide and prevents precipitation of elemental sulfur.

  19. Techno-economic Analysis for the Thermochemical Conversion of Lignocellulosic Biomass to Ethanol via Acetic Acid Synthesis

    SciTech Connect

    Zhu, Yunhua; Jones, Susanne B.

    2009-04-01

    Biomass is a renewable energy resource that can be converted into liquid fuel suitable for transportation applications. As a widely available biomass form, lignocellulosic biomass can have a major impact on domestic transportation fuel supplies and thus help meet the Energy Independence and Security Act renewable energy goals (U.S. Congress 2007). This study performs a techno-economic analysis of the thermo chemical conversion of biomass to ethanol, through methanol and acetic acid, followed by hydrogenation of acetic acid to ethanol. The conversion of syngas to methanol and methanol to acetic acid are well-proven technologies with high conversions and yields. This study was undertaken to determine if this highly selective route to ethanol could provide an already established economically attractive route to ethanol. The feedstock was assumed to be wood chips at 2000 metric ton/day (dry basis). Two types of gasification technologies were evaluated: an indirectly-heated gasifier and a directly-heated oxygen-blown gasifier. Process models were developed and a cost analysis was performed. The carbon monoxide used for acetic acid synthesis from methanol and the hydrogen used for hydrogenation were assumed to be purchased and not derived from the gasifier. Analysis results show that ethanol selling prices are estimated to be $2.79/gallon and $2.81/gallon for the indirectly-heated gasifier and the directly-heated gasifier systems, respectively (1stQ 2008$, 10% ROI). These costs are above the ethanol market price for during the same time period ($1.50 - $2.50/gal). The co-production of acetic acid greatly improves the process economics as shown in the figure below. Here, 20% of the acetic acid is diverted from ethanol production and assumed to be sold as a co-product at the prevailing market prices ($0.40 - $0.60/lb acetic acid), resulting in competitive ethanol production costs.

  20. The effects of acetaldehyde, glyoxal and acetic acid on the heterogeneous reaction of nitrogen dioxide on gamma-alumina.

    PubMed

    Sun, Zhenyu; Kong, Lingdong; Ding, Xiaoxiao; Du, Chengtian; Zhao, Xi; Chen, Jianmin; Fu, Hongbo; Yang, Xin; Cheng, Tiantao

    2016-04-14

    Heterogeneous reactions of nitrogen oxides on the surface of aluminium oxide result in the formation of adsorbed nitrite and nitrate. However, little is known about the effects of other species on these heterogeneous reactions and their products. In this study, diffuse reflectance infrared spectroscopy (DRIFTS) was used to analyze the process of the heterogeneous reaction of NO2 on the surface of aluminium oxide particles in the presence of pre-adsorbed organic species (acetaldehyde, glyoxal and acetic acid) at 298 K and reveal the influence of these organic species on the formation of adsorbed nitrite and nitrate. It was found that the pre-adsorption of organic species (acetaldehyde, glyoxal and acetic acid) on γ-Al2O3 could suppress the formation of nitrate to different extents. Under the same experimental conditions, the suppression of the formation of nitrate by the pre-adsorption of acetic acid is much stronger than that by pre-adsorption of acetaldehyde and glyoxal, indicating that the influence of acetic acid on the heterogeneous reaction of NO2 is different from that of acetaldehyde and glyoxal. Surface nitrite is formed and identified to be an intermediate product. For the heterogeneous reaction of NO2 on the surface of γ-Al2O3 with and without the pre-adsorption of acetaldehyde and glyoxal, it is firstly formed and then gradually disappears as the reaction proceeds, but for the reaction with the pre-adsorption of acetic acid, it is the final main product besides nitrate. This indicates that the pre-adsorption of acetic acid would promote the formation of nitrite, while the others would not change the trend of the formation of nitrite. The possible influence mechanisms of the pre-adsorption of acetaldehyde, glyoxal and acetic acid on the heterogeneous conversion of NO2 on γ-Al2O3 are proposed and atmospheric implications based on these results are discussed. PMID:26745767

  1. The kinetics of process dependent ammonia inhibition of methanogenesis from acetic acid.

    PubMed

    Wilson, Christopher Allen; Novak, John; Takacs, Imre; Wett, Bernhard; Murthy, Sudhir

    2012-12-01

    Advanced anaerobic digestion processes aimed at improving the methanization of sewage sludge may be potentially impaired by the production of inhibitory compounds (e.g. free ammonia). The result of methanogenic inhibition is relatively high effluent concentrations of acetic acid and other soluble organics, as well as reduced methane yields. An extreme example of such an advanced process is the thermal hydrolytic pretreatment of sludge prior to high solids digestion (THD). Compared to a conventional mesophilic anaerobic digestion process (MAD), THD operates in a state of constant inhibition driven by high free ammonia concentrations, and elevated pH values. As such, previous investigations of the kinetics of methanogenesis from acetic acid under uninhibited conditions do not necessarily apply well to the modeling of extreme processes such as THD. By conducting batch ammonia toxicity assays using biomass from THD and MAD reactors, we compared the response of these communities over a broad range of ammonia inhibition. For both processes, increased inhibitor concentrations resulted in a reduction of biomass growth rate (r(max) = μ(max)∙X) and a resulting decrease in the substrate half saturation coefficient (K(S)). These two parameters exhibited a high degree of correlation, suggesting that for a constant transport limited system, the K(S) was mostly a linear function of the growth rate. After correcting for reactor pH and temperature, we found that the THD and MAD biomass were both able to perform methanogenesis from acetate at high free ammonia concentrations (equivalent to 3-5 g/L total ammonia nitrogen), albeit at less than 30% of their respective maximum rates. The reduction in methane production was slightly less pronounced for the THD biomass than for MAD, suggesting that the long term exposure to ammonia had selected for a methanogenic pathway less dependent on those organisms most sensitive to ammonia inhibition (i.e. aceticlastic methanogens). PMID

  2. Protective effect of Dillenia indica L. on acetic acid induced colitis in mice.

    PubMed

    Somani, S J; Badgujar, L B; Sutariya, B K; Saraf, M N

    2014-09-01

    The inflammatory bowel disease (IBD) is an idiopathic, immune mediated and chronic inflammation of the intestine. The study aimed to elucidate the ameliorative effect of methanolic extract of Dillenia indica (DIME), hexane fraction (HFDI) and chloroform fraction (CFDI) of Dillenia indica in acetic acid induced experimental colitis in mice. Macroscopic score, colon weight, colonic catalase (CAT), superoxide dismutase (SOD), glutathione (GSH), myeloperoxidase (MPO), malondialdehyde (MDA), tumor necrosis factor (TNF-alpha), and histological changes were recorded after the treatment regimen of 7 days. Intra-rectal instillation of acetic acid caused enhanced macroscopic score, colon weight, colonic MPO, MDA, and TNF-alpha level. It caused significant decreased level of CAT, SOD and GSH. DIME (800 mg/kg), HFDI (200 mg/kg) and CFDI (200 mg/kg) treatment exhibited significant effect in lowering macroscopic score, colon weight, MPO, MDA, TNF-alpha levels and elevation of CAT, GSH and SOD levels. The results suggest that D. indica has ameliorating effects on experimental colitis by inhibiting the proinflammatory mediators like TNF-alpha production. PMID:25241587

  3. Azithromycin and erythromycin ameliorate the extent of colonic damage induced by acetic acid in rats

    SciTech Connect

    Mahgoub, Afaf . E-mail: afaf_mahgoub@yahoo.com; El-Medany, Azza; Mustafa, Ali; Arafah, Maha; Moursi, Mahmoud

    2005-05-15

    Ulcerative colitis is a common inflammatory bowel disease (IBD) of unknown etiology. Recent studies have revealed the role of some microorganisms in the initiation and perpetuation of IBD. The role of antibiotics in the possible modulation of colon inflammation is still uncertain. In this study, we evaluated the effects of two macrolides, namely azithromycin and erythromycin, at different doses on the extent and severity of ulcerative colitis caused by intracolonic administration of 3% acetic acid in rats. The lesions and the inflammatory response were assessed by histology and measurement of myeloperoxidase (MPO) activity, nitric oxide synthetase (NOS) and tumor necrosis factor alpha (TNF{alpha}) in colonic tissues. Inflammation following acetic acid instillation was characterized by oedema, diffuse inflammatory cell infiltration and necrosis. Increase in MPO, NOS and TNF{alpha} was detected in the colonic tissues. Administration of either azithromycin or erythromycin at different dosage (10, 20 and 40 mg/kg orally, daily for 5 consecutive days) significantly (P < 0.05) reduced the colonic damage, MPO and NOS activities as well as TNF{alpha} level. This reduction was highly significant with azithromycin when given at a dose of 40 mg/kg. It is concluded that azithromycin and erythromycin may have a beneficial therapeutic role in ulcerative colitis.

  4. Photolytic degradation of chlorophenols from industrial wastewaters by organic oxidants peroxy acetic acid, para nitro benzoic acid and methyl ethyl ketone peroxide: identification of reaction products.

    PubMed

    Sharma, Swati; Mukhopadhyay, Mausumi; Murthy, Zagabathuni Venkata Panchakshari

    2014-01-01

    In this investigation, chlorophenol (CP) containing industrial wastewater was remediated by ultraviolet irradiation in conjunction with organic oxidants, peroxy acetic acid (PAA); para nitro benzoic acid (PNBA); and methyl ethyl ketone peroxide (MEKP). CP mineralization was studied with regard to chemical oxygen demand (COD) and chloride ion release under identical test conditions. COD depletion to the extent of 81% by PAA, 66% by PNBA, and 67% by MEKP was noted along with an upwardly mobile trend of chloride ion release upon irradiation of samples at 254 nm. A 90-99% decrease in CP concentration (as per high pressure liquid chromatography (HPLC) analysis) was achieved with an additional 15.0 ml of organic oxidant in all cases. Gas chromatography high resolution mass spectroscopy (GC-HRMS) results also indicated the formation of such reaction products as are free from chlorine substitutions. This treatment also leads to total decolorization of the collected samples. PMID:24647192

  5. Matrix Isolation IR Spectroscopy of 1:1 Complexes of Acetic Acid and Trihaloacetic Acids with Water and Benzene

    NASA Astrophysics Data System (ADS)

    Banerjee, Pujarini; Chakraborty, Tapas

    2015-06-01

    A comparative study of infrared spectral effects for 1:1 complex formation of acetic acid (AA), trifluoroacetic acid (TFAA) and trichloroacetic acid (TFAA) with water and benzene has been carried out under a matrix isolation environment. Despite the large difference in aqueous phase acidities of the three acids, the measured νb{OH}stretching frequencies of the monomers of the three molecules are found to be almost same, and in agreement with gas phase electronic structure calculations. Intrinsic acidities are expressed only in the presence of the proton acceptors, water or benzene. Although electronic structure calculations predict distinct νb{OH} red-shifts for all three acids, the measured spectral features for TCAA and TFAA in this range do not allow unambiguous assignments for the 1:1 complex. On the other hand, the spectral changes in the νb{C=O} region are more systematic, and the observed changes are consistent with predictions of theory. Components of overall binding energy of each complex have been obtained from energy decomposition analysis, which allows determination of the relative contributions of various physical forces towards overall stability of the complexes, and the details will be discussed in the talk.

  6. Amonia gas: an improved reagent for chemical ionization mass spectrometry of bile acid methyl ester acetates

    SciTech Connect

    DeMark, B.R.; Klein, P.D.

    1981-01-01

    The ammonia chemical ionization mass spectra of 28 methyl ester acetate derivatives of bile acids and related compounds have been determined by gas-liquid chromatography-mass spectrometry. Advantages of ammonia ionization over the previously studied isobutane ionization include a 130 to 270% enhancement in the sensitivity of base peak monitoring, and direct determination of molecular weight from the base peak (M + NH/sub 4//sup +/) in the mass spectrum of any of the derivatives. Minor ions in the ammonia spectra also allow selective detection of 3-keto compounds and can indicate unsaturation or double bond conjugation in the molecule. The significance of these studies for the detection and quantitation of bile acids is discussed. 2 tables.

  7. Liquid-liquid equilibria of the ternary system water + acetic acid + 1-hexanol

    SciTech Connect

    Fahim, M.A.; Al-Muhtaseb, S.A.; Al-Nashef, I.M.

    1997-01-01

    The recovery of organic acids from dilute solutions resulting from fermentation processes is important and many solvents have been tried to improve such recovery. Liquid-liquid equilibria for the ternary system water + acetic acid + 1-hexanol were measured over a temperature range of (288 to 323) K. The results were used to estimate the interaction parameters between each of the three compounds for the NRTL and UNIQUAC models and between each of the main groups of H{sub 2}O, CH{sub 2} (paraffinic CH{sub 2}), OH, and COOH for the UNIFAC model as a function of temperature. The estimated interaction parameters were successfully used to predict the equilibrium compositions by the three models. The NRTL equation was the most accurate model in correlating the overall equilibrium compositions of the studied system. The UNIQUAC and UNIFAC models satisfactorily predicted the equilibrium compositions.

  8. Rapid identification of acetic acid bacteria using MALDI-TOF mass spectrometry fingerprinting.

    PubMed

    Andrés-Barrao, Cristina; Benagli, Cinzia; Chappuis, Malou; Ortega Pérez, Ruben; Tonolla, Mauro; Barja, François

    2013-03-01

    Acetic acid bacteria (AAB) are widespread microorganisms characterized by their ability to transform alcohols and sugar-alcohols into their corresponding organic acids. The suitability of matrix-assisted laser desorption-time of flight mass spectrometry (MALDI-TOF MS) for the identification of cultured AAB involved in the industrial production of vinegar was evaluated on 64 reference strains from the genera Acetobacter, Gluconacetobacter and Gluconobacter. Analysis of MS spectra obtained from single colonies of these strains confirmed their basic classification based on comparative 16S rRNA gene sequence analysis. MALDI-TOF analyses of isolates from vinegar cross-checked by comparative sequence analysis of 16S rRNA gene fragments allowed AAB to be identified, and it was possible to differentiate them from mixed cultures and non-AAB. The results showed that MALDI-TOF MS analysis was a rapid and reliable method for the clustering and identification of AAB species. PMID:23182036

  9. An intercomparison of measurement systems for vapor and particulate phase concentrations of formic and acetic acids

    NASA Technical Reports Server (NTRS)

    Keene, William C.; Talbot, Robert W.; Andreae, Meinrat O.; Beecher, Kristene; Berresheim, Harold

    1989-01-01

    During June 1986, eight systems for measuring vapor phase and four for measuring particulate phase concentrations of formic acid (HCOOH) and acetic acid (CH3COOH) were intercompared in central Virginia. HCOOH and CH3COOH vapors were sampled by condensate, mist, Chromosorb 103 GC resin, NaOH-coated annular denuders, NaOH-impregnated quartz filters, K2CO3 and NaCO3-impregnated cellulose filters, and Nylasorb membranes. Atmospheric aerosol was collected on Teflon and Nuclepore filters using both hi-vol and lo-vol systems to measure particulate phase concentrations. Performances of the mist chamber and K2CO3-impregnated filter techniques were evaluated using zero air and ambient air spiked with HCOOH(g) and CH3COOH(g), and formaldehyde from permeation sources. The advantages and drawbacks of these methods are reported and discussed.

  10. Acetic acid-assisted hydrothermal fractionation of empty fruit bunches for high hemicellulosic sugar recovery with low byproducts.

    PubMed

    Kim, Dong Young; Um, Byung Hwan; Oh, Kyeong Keun

    2015-07-01

    Xylose, mannose, and galactose (xmg) recovery from empty fruit bunches using acetic acid-assisted hydrothermal (AAH) fractionation method was investigated. Acetic acid has been demonstrated to be effective in xmg recovery in comparison with the liquid hot-water (LHW) fractionation. The maximum xmg recovery yield (50.7 %) from the empty fruit bunch (EFB) was obtained using AAH fractionation at optimum conditions (6.9 wt.% acetic acid at 170 °C and for 18 min); whereas, only 16.2 % of xmg recovery was obtained from the LHW fractionation at the same reaction conditions (170 °C and 18 min). Releasing out the glucose from EFB was kept at low level (<1.0 %) through all tested conditions and consequently negligible 5-HMF and formic acid were analyzed in the hydrolyzate. The production of furfural was also resulted with extremely low level (1.0 g/L). PMID:25962829

  11. Global insights into acetic acid resistance mechanisms and genetic stability of Acetobacter pasteurianus strains by comparative genomics

    PubMed Central

    Wang, Bin; Shao, Yanchun; Chen, Tao; Chen, Wanping; Chen, Fusheng

    2015-01-01

    Acetobacter pasteurianus (Ap) CICC 20001 and CGMCC 1.41 are two acetic acid bacteria strains that, because of their strong abilities to produce and tolerate high concentrations of acetic acid, have been widely used to brew vinegar in China. To globally understand the fermentation characteristics, acid-tolerant mechanisms and genetic stabilities, their genomes were sequenced. Genomic comparisons with 9 other sequenced Ap strains revealed that their chromosomes were evolutionarily conserved, whereas the plasmids were unique compared with other Ap strains. Analysis of the acid-tolerant metabolic pathway at the genomic level indicated that the metabolism of some amino acids and the known mechanisms of acetic acid tolerance, might collaboratively contribute to acetic acid resistance in Ap strains. The balance of instability factors and stability factors in the genomes of Ap CICC 20001 and CGMCC 1.41 strains might be the basis for their genetic stability, consistent with their stable industrial performances. These observations provide important insights into the acid resistance mechanism and the genetic stability of Ap strains and lay a foundation for future genetic manipulation and engineering of these two strains. PMID:26691589

  12. Global insights into acetic acid resistance mechanisms and genetic stability of Acetobacter pasteurianus strains by comparative genomics.

    PubMed

    Wang, Bin; Shao, Yanchun; Chen, Tao; Chen, Wanping; Chen, Fusheng

    2015-01-01

    Acetobacter pasteurianus (Ap) CICC 20001 and CGMCC 1.41 are two acetic acid bacteria strains that, because of their strong abilities to produce and tolerate high concentrations of acetic acid, have been widely used to brew vinegar in China. To globally understand the fermentation characteristics, acid-tolerant mechanisms and genetic stabilities, their genomes were sequenced. Genomic comparisons with 9 other sequenced Ap strains revealed that their chromosomes were evolutionarily conserved, whereas the plasmids were unique compared with other Ap strains. Analysis of the acid-tolerant metabolic pathway at the genomic level indicated that the metabolism of some amino acids and the known mechanisms of acetic acid tolerance, might collaboratively contribute to acetic acid resistance in Ap strains. The balance of instability factors and stability factors in the genomes of Ap CICC 20001 and CGMCC 1.41 strains might be the basis for their genetic stability, consistent with their stable industrial performances. These observations provide important insights into the acid resistance mechanism and the genetic stability of Ap strains and lay a foundation for future genetic manipulation and engineering of these two strains. PMID:26691589

  13. Developmental toxicity of mixtures: the water disinfection by-products dichloro-, dibromo- and bromochloro acetic acid in rat embryo culture

    EPA Science Inventory

    The chlorination of drinking water results in production of numerous disinfection by-products (DBPs). One of the important classes of DBPs is the haloacetic acids. We have previously shown that the haloacetic acids (HAs), dichloro (DCA), dibromo (DBA) and bromochloro (BCA) acetic...

  14. Global insights into acetic acid resistance mechanisms and genetic stability of Acetobacter pasteurianus strains by comparative genomics

    NASA Astrophysics Data System (ADS)

    Wang, Bin; Shao, Yanchun; Chen, Tao; Chen, Wanping; Chen, Fusheng

    2015-12-01

    Acetobacter pasteurianus (Ap) CICC 20001 and CGMCC 1.41 are two acetic acid bacteria strains that, because of their strong abilities to produce and tolerate high concentrations of acetic acid, have been widely used to brew vinegar in China. To globally understand the fermentation characteristics, acid-tolerant mechanisms and genetic stabilities, their genomes were sequenced. Genomic comparisons with 9 other sequenced Ap strains revealed that their chromosomes were evolutionarily conserved, whereas the plasmids were unique compared with other Ap strains. Analysis of the acid-tolerant metabolic pathway at the genomic level indicated that the metabolism of some amino acids and the known mechanisms of acetic acid tolerance, might collaboratively contribute to acetic acid resistance in Ap strains. The balance of instability factors and stability factors in the genomes of Ap CICC 20001 and CGMCC 1.41 strains might be the basis for their genetic stability, consistent with their stable industrial performances. These observations provide important insights into the acid resistance mechanism and the genetic stability of Ap strains and lay a foundation for future genetic manipulation and engineering of these two strains.

  15. Draft Genome Sequences of Gluconobacter cerinus CECT 9110 and Gluconobacter japonicus CECT 8443, Acetic Acid Bacteria Isolated from Grape Must

    PubMed Central

    Sainz, Florencia

    2016-01-01

    We report here the draft genome sequences of Gluconobacter cerinus strain CECT9110 and Gluconobacter japonicus CECT8443, acetic acid bacteria isolated from grape must. Gluconobacter species are well known for their ability to oxidize sugar alcohols into the corresponding acids. Our objective was to select strains to oxidize effectively d-glucose. PMID:27365351

  16. Morphological and phase evolution of TiO 2 nanocrystals prepared from peroxotitanate complex aqueous solution: Influence of acetic acid

    NASA Astrophysics Data System (ADS)

    Chang, Jeong Ah; Vithal, Muga; Baek, In Chan; Seok, Sang Il

    2009-04-01

    Nanosized anatase and rutile TiO 2 having different shape, phase and size have been prepared from aqueous solutions of peroxo titanium complex starting from titanium(IV) isopropoxide (TTIP), acetic acid and hydrogen peroxide (H 2O 2) in water/isopropanol media by a facile sol-gel process. The TiO 2 nanocrystals are characterized by powder X-ray diffraction (XRD), Raman spectroscopy, FT-IR spectroscopy, TEM, high resolution transmission electron microscopy (HRTEM) and selected area electron diffraction (SAED) techniques. The influence of pH and the sequence of addition of reaction contents on the phase and morphology of TiO 2 are studied. The reasons for the observation of only anatase and/or mixture of anatase and rutile are given.

  17. Quantifying Effect of Lactic, Acetic, and Propionic Acids on Growth of Molds Isolated from Spoiled Bakery Products.

    PubMed

    Dagnas, Stéphane; Gauvry, Emilie; Onno, Bernard; Membré, Jeanne-Marie

    2015-09-01

    The combined effect of undissociated lactic acid (0 to 180 mmol/liter), acetic acid (0 to 60 mmol/liter), and propionic acid (0 to 12 mmol/liter) on growth of the molds Aspergillus niger, Penicillium corylophilum, and Eurotium repens was quantified at pH 3.8 and 25°C on malt extract agar acid medium. The impact of these acids on lag time for growth (λ) was quantified through a gamma model based on the MIC. The impact of these acids on radial growth rate (μ) was analyzed statistically through polynomial regression. Concerning λ, propionic acid exhibited a stronger inhibitory effect (MIC of 8 to 20 mmol/liter depending on the mold species) than did acetic acid (MIC of 23 to 72 mmol/liter). The lactic acid effect was null on E. repens and inhibitory on A. niger and P. corylophilum. These results were validated using independent sets of data for the three acids at pH 3.8 but for only acetic and propionic acids at pH 4.5. Concerning μ, the effect of acetic and propionic acids was slightly inhibitory for A. niger and P. corylophilum but was not significant for E. repens. In contrast, lactic acid promoted radial growth of all three molds. The gamma terms developed here for these acids will be incorporated in a predictive model for temperature, water activity, and acid. More generally, results for μ and λ will be used to identify and evaluate solutions for controlling bakery product spoilage. PMID:26319723

  18. PHOTOLYSIS RATES OF (2,4,5-TRICHLOROPHENOXY)ACETIC ACID AND 4-AMINO-3,5,6-TRICHLOROPICOLINIC ACID IN NATURAL WATERS

    EPA Science Inventory

    Photoreactions of (2,45-trichlorophenoxy) acetic acid (2,4,5-T) and 4-amino-3,5,6-trichloropicolinic acid (picloram) were studied in distilled water, natural water samples, fulvic acid solutions, and solutions containing iron (III) and/or hydrogen peroxide to determine the effect...

  19. Absence of Rtt109p, a fungal-specific histone acetyltransferase, results in improved acetic acid tolerance of Saccharomyces cerevisiae.

    PubMed

    Cheng, Cheng; Zhao, Xinqing; Zhang, Mingming; Bai, Fengwu

    2016-03-01

    RTT109 is a histone acetyltransferase for the acetylation of histone H3. It is still not clear whether RTT109 plays a role in regulation of gene expression under environmental stresses. In this study, the involvement of RTT109 in acetic acid stress tolerance of Saccharomyces cerevisiae was investigated. It was revealed that the absence of RTT109 enhanced resistance to 5.5 g L(-1) acetic acid, which was indicated by improved growth of RTT109Δ mutant compared with that of the wild-type BY4741 strain. Meanwhile, the lag phase was shortened for 48 h and glucose consumption completed 36 h in advance for RTT109Δ mutant compared to the wild-type strain, with ethanol production rate increased from 0.39 to 0.60 g L(-1) h(-1). Significantly, elevated transcription levels of HSP12, CTT1 and GSH1, as well as increased activities of antioxidant enzymes were observed in RTT109Δ under acetic acid stress. Improved flocculation of RTT109Δ compared to that of the control strain BY4741 under the acetic acid stress was also observed. These results suggest that the absence of RTT109 not only activates transcription of stress responsive genes, but also improves resistance to oxidative stress, which ultimately contributes to improved acetic acid tolerance in S. cerevisiae. PMID:26851403

  20. Helpfulness of the combination of acetic acid and FICE in the detection of Barrett's epithelium and Barrett's associated neoplasias

    PubMed Central

    Camus, Marine; Coriat, Romain; Leblanc, Sarah; Brezault, Catherine; Terris, Benoit; Pommaret, Elise; Gaudric, Marianne; Chryssostalis, Ariane; Prat, Frederic; Chaussade, Stanislas

    2012-01-01

    AIM: To investigate the mucosal morphology in Barrett’s oesophagus by chromo and magnifying endoscopy. METHODS: A prospective pilot study at a tertiary medical centre was conducted to evaluate the use of acetic acid pulverisation combined with virtual chromoendoscopy using Fujinon intelligent chromoendoscopy (FICE) for semiological characterization of the mucosal morphology in Barrett’s oesophagus and its neoplastic complications. Upper endoscopy using high definition white light, 2% acid acetic pulverisation and FICE with high definition videoendoscopy were performed in 20 patients including 18 patients who presented with aspects of Barrett’s oesophagus at endoscopy examination. Two patients used as controls had normal endoscopy and histological results. Prospectively, videos were watched blind from histological results by three trained FICE technique endoscopists. RESULTS: The videos of patients with high-grade dysplasia showed an irregular mucosal pattern in 14% using high definition white light endoscopy and in 100% using acid acetic-FICE combined. Videos did not identify irregular vascular patterns using high definition white light endoscopy, while acid acetic-FICE combined visualised one in 86% of cases. CONCLUSION: Combined acetic acid and FICE is a promising method for screening high-grade dysplasia and early cancer in Barrett’s oesophagus. PMID:22563172

  1. Short-Chain Fatty Acid Acetate Stimulates Adipogenesis and Mitochondrial Biogenesis via GPR43 in Brown Adipocytes.

    PubMed

    Hu, Jiamiao; Kyrou, Ioannis; Tan, Bee K; Dimitriadis, Georgios K; Ramanjaneya, Manjunath; Tripathi, Gyanendra; Patel, Vanlata; James, Sean; Kawan, Mohamed; Chen, Jing; Randeva, Harpal S

    2016-05-01

    Short-chain fatty acids play crucial roles in a range of physiological functions. However, the effects of short-chain fatty acids on brown adipose tissue have not been fully investigated. We examined the role of acetate, a short-chain fatty acid formed by fermentation in the gut, in the regulation of brown adipocyte metabolism. Our results show that acetate up-regulates adipocyte protein 2, peroxisomal proliferator-activated receptor-γ coactivator-1α, and uncoupling protein-1 expression and affects the morphological changes of brown adipocytes during adipogenesis. Moreover, an increase in mitochondrial biogenesis was observed after acetate treatment. Acetate also elicited the activation of ERK and cAMP response element-binding protein, and these responses were sensitive to G(i/o)-type G protein inactivator, Gβγ-subunit inhibitor, phospholipase C inhibitor, and MAPK kinase inhibitor, indicating a role for the G(i/o)βγ/phospholipase C/protein kinase C/MAPK kinase signaling pathway in these responses. These effects of acetate were mimicked by treatment with 4-chloro-α-(1-methylethyl)-N-2-thiazolylbenzeneacetamide, a synthetic G protein-coupled receptor 43 (GPR43) agonist and were impaired in GPR43 knockdown cells. Taken together, our results indicate that acetate may have important physiological roles in brown adipocytes through the activation of GPR43. PMID:26990063

  2. Cloning and biochemical characterization of indole-3-acetic acid-amino acid synthetase PsGH3 from pea.

    PubMed

    Ostrowski, Maciej; Mierek-Adamska, Agnieszka; Porowińska, Dorota; Goc, Anna; Jakubowska, Anna

    2016-10-01

    Phytohormone conjugation is one of the mechanisms that maintains a proper hormonal homeostasis and that is necessary for the realization of physiological responses. Gretchen Hagen 3 (GH3) acyl acid amido synthetases convert indole-3-acetic acid (IAA) to IAA-amino acid conjugates by ATP-dependent reactions. IAA-aspartate (IAA-Asp) exists as a predominant amide conjugate of auxin in pea tissues and acts as an intermediate during IAA catabolism. Here we report a novel recombinant indole-3-acetic acid-amido synthetase in Pisum sativum. In silico analysis shows that amino acid sequence of PsGH3 has the highest homology to Medicago truncatula GH3.3. The recombinant His-tag-PsGH3 fusion protein has been obtained in E. coli cells and is a soluble monomeric polypeptide with molecular mass of 69.18 kDa. The PsGH3 was purified using Ni(2+)-affinity chromatography and native PAGE. Kinetic analysis indicates that the enzyme strongly prefers IAA and L-aspartate as substrates for conjugation revealing Km(ATP) = 0.49 mM, Km(L-Asp) = 2.2 mM, and Km(IAA) = 0.28 mM. Diadenosine pentaphosphate (Ap5A) competes with ATP for catalytic site and diminishes the PsGH3 affinity toward ATP approximately 1.11-fold indicating Ki = 8.5 μM. L-Tryptophan acts as an inhibitor of IAA-amido synthesizing activity by competition with L-aspartate. Inorganic pyrophosphatase (PPase) hydrolyzing pyrophosphate to two phosphate ions, potentiates IAA-Asp synthetase activity of PsGH3. Our results demonstrate that PsGH3 is a novel enzyme that is involved in auxin metabolism in pea seeds. PMID:27235647

  3. Enhancing acetone biosynthesis and acetone-butanol-ethanol fermentation performance by co-culturing Clostridium acetobutylicum/Saccharomyces cerevisiae integrated with exogenous acetate addition.

    PubMed

    Luo, Hongzhen; Ge, Laibing; Zhang, Jingshu; Ding, Jian; Chen, Rui; Shi, Zhongping

    2016-01-01

    Acetone is the major by-product in ABE fermentations, most researches focused on increasing butanol/acetone ratio by decreasing acetone biosynthesis. However, economics of ABE fermentation industry strongly relies on evaluating acetone as a valuable platform chemical. Therefore, a novel ABE fermentation strategy focusing on bio-acetone production by co-culturing Clostridium acetobutylicum/Saccharomyces cerevisiae with exogenous acetate addition was proposed. Experimental and theoretical analysis revealed the strategy could, enhance C. acetobutylicum survival oriented amino acids assimilation in the cells; control NADH regeneration rate at moderately lower level to enhance acetone synthesis but without sacrificing butanol production; enhance the utilization ability of C. acetobutylicum on glucose and direct most of extra consumed glucose into acetone/butanol synthesis routes. By implementing the strategy using synthetic or acetate fermentative supernatant, acetone concentrations increased to 8.27-8.55g/L from 5.86g/L of the control, while butanol concentrations also elevated to the higher levels of 13.91-14.23g/L from 11.63g/L simultaneously. PMID:26476171

  4. Visual Inspection after Acetic Acid (VIA) Is Highly Heterogeneous in Primary Cervical Screening in Amazonian Peru

    PubMed Central

    Almonte, Maribel; Ferreccio, Catterina; Luciani, Silvana; Gonzales, Miguel; Delgado, Jose M.; Santos, Carlos; Alvarez, Manuel; Cuzick, Jack; Sasieni, Peter

    2015-01-01

    Background Conventional cytology (Pap) and visual inspection after the application of acetic acid (VIA) are currently used in primary screening in Peru. Studies suggest that the quality of VIA is highly variable. Over 36 000 women were screened with Pap and VIA in the TATI (Tamizaje y Tratamiento Inmediato de Lesiones Cervico-uterinas) project conducted in Amazonian Peru. Within a nested study to compare several screening techniques (C-TATI), a total of 5435 women were additionally screened with liquid-based cytology (LBC) and high-risk human papillomavirus testing (HR-HPV). We investigate the variation of positivity rates of VIA, Pap, LBC and HR-HPV in C-TATI and of VIA in the full TATI intervention. Methods At the screening visit, midwives collected three cervical samples for Pap, LBC and HC2 before performing VIA. The dispersion factor “D” (D = Pearson chi-square value/degrees-of-freedom) was used to measure the variability of tests results. Within C-TATI, the variability of positivity rates of VIA, Pap, LBC and HR-HPV was also graphically assessed with box- and scatter plots by midwife and month of screening. Funnel plots and smoothed scatter plots were used to correlate the variation of VIA by the number of examinations performed by each midwife over the full TATI intervention. Results Consistently over TATI, VIA results were highly variable, independently of the examiner, the time when the test was performed and the number of tests the examiner performed (D>6, p-values<0.001). In C-TATI, VIA results varied the most while those of HR-HPV varied the least (Ds>25, p-values<0.001 for VIA, Ds<1.6, p-values>0.05 for HR-HPV). No evidence for correlation between the number of VIAs done per midwife and the variability of VIA results was observed. Conclusion The lack of over-dispersion for HR-HPV detection suggests that the variable VIA results do not reflect true variation in underlying disease, but a lack of consistency in human judgement. PMID:25635965

  5. Protective effects of N-acetylcysteine on acetic acid-induced colitis in a porcine model

    PubMed Central

    2013-01-01

    Background Ulcerative colitis is a chronic inflammatory disease and involves multiple etiological factors. Acetic acid (AA)-induced colitis is a reproducible and simple model, sharing many characteristics with human colitis. N-acetylcysteine (NAC) has been widely used as an antioxidant in vivo and in vitro. NAC can affect several signaling pathways involving in apoptosis, angiogenesis, cell growth and arrest, redox-regulated gene expression, and inflammatory response. Therefore, NAC may not only protect against the direct injurious effects of oxidants, but also beneficially alter inflammatory events in colitis. This study was conducted to investigate whether NAC could alleviate the AA-induced colitis in a porcine model. Methods Weaned piglets were used to investigate the effects of NAC on AA-induced colitis. Severity of colitis was evaluated by colon histomorphology measurements, histopathology scores, tissue myeloperoxidase activity, as well as concentrations of malondialdehyde and pro-inflammatory mediators in the plasma and colon. The protective role of NAC was assessed by measurements of antioxidant status, growth modulator, cell apoptosis, and tight junction proteins. Abundances of caspase-3 and claudin-1 proteins in colonic mucosae were determined by the Western blot method. Epidermal growth factor receptor, amphiregulin, tumor necrosis factor-alpha (TNF-α), and toll-like receptor 4 (TLR4) mRNA levels in colonic mucosae were quantified using the real-time fluorescent quantitative PCR. Results Compared with the control group, AA treatment increased (P < 0.05) the histopathology scores, intraepithelial lymphocyte (IEL) numbers and density in the colon, myeloperoxidase activity, the concentrations of malondialdehyde and pro-inflammatory mediators in the plasma and colon, while reducing (P < 0.05) goblet cell numbers and the protein/DNA ratio in the colonic mucosa. These adverse effects of AA were partially ameliorated (P < 0.05) by dietary

  6. Oleanolic acid acetate inhibits atopic dermatitis and allergic contact dermatitis in a murine model

    SciTech Connect

    Choi, Jin Kyeong; Oh, Hyun-Mee; Lee, Soyoung; Park, Jin-Woo; Khang, Dongwoo; Lee, Seung Woong; Lee, Woo Song; Rho, Mun-Chual; Kim, Sang-Hyun

    2013-05-15

    Atopic dermatitis (AD) and allergic contact dermatitis (ACD) are common allergic and inflammatory skin diseases caused by a combination of eczema, scratching, pruritus, and cutaneous sensitization with allergens. This paper examines whether oleanolic acid acetate (OAA) modulates AD and ACD symptoms by using an existing AD model based on the repeated local exposure of mite extract (Dermatophagoides farinae extract, DFE) and 2,4-dinitrochlorobenzene to the ears of BALB/c mice. In addition, the paper uses a 2,4-dinitrofluorobenzene-sensitized local lymph node assay (LLNA) for the ACD model. The oral administration of OAA over a four-week period attenuated AD symptoms in terms of decreased skin lesions, epidermal thickness, the infiltration of immune cells (CD4{sup +} cells, eosinophils, and mast cells), and serum IgE, IgG2a, and histamine levels. The gene expression of Th1, Th2, Th17, and Th22 cytokines was reduced by OAA in the lymph node and ear tissue, and the LLNA verified that OAA suppressed ACD. The oral administration of OAA over a three-day period attenuated ACD symptoms in terms of ear thickness, lymphocyte proliferation, and serum IgG2a levels. The gene expression of Th1, Th2, and Th17 cytokines was reduced by OAA in the thymus and ear tissue. Finally, to define the underlying mechanism, this paper uses a TNF-α/IFN-γ-activated human keratinocyte (HaCaT) model. OAA inhibited the expression of cytokines and chemokines through the downregulation of NF-κB and MAPKs in HaCaT cells. Taken together, the results indicate that OAA inhibited AD and ACD symptoms, suggesting that OAA may be effective in treating allergic skin disorders. - Highlights: • OAA reduced both acute and chronic AD symptoms. • OAA had a controlling effect on the immune reaction for ACD. • The effect of OAA on allergic skin disorders was comparable to the cyclosporine A. • OAA might be a candidate for the treatment of allergic skin disorders.

  7. Biotransformation of p-coumaric acid and 2,4-dichlorophenoxy acetic acid by Azotobacter sp. strain SSB81.

    PubMed

    Gauri, Samiran S; Mandal, Santi M; Dey, Satyahari; Pati, Bikas R

    2012-12-01

    A comprehensive study was made on biotransformation of p-coumaric acid and 2,4-dichlorophenoxyacetic acid by an Azotobacter sp. strain SSB81. The strain was able to tolerate a high amount of both the phenolic acids and p-coumaric acid degraded maximum (50%) than 2,4-D (29%) after five days of incubation. The intermediate products during transformation have been identified and quantified using UV-Vis and LC-MS/MS analysis. Para-coumaric acid was degraded via p-hydroxybenzoic acid and protocatechuic acid, a non-oxidative pathway whereas 2,4-D via 4-chlorophenoxyacetic acid, 4-chlorophenol and 4-chlorocatechol, an oxidative pathway. The results suggest that SSB81 developed both the oxidative and non-oxidative pathway to degrade the soil accumulated phenolic acids. Thus, Azotobacter provides an advantage to reduce the toxic level of soil accumulated phenolic acids in addition to increase the soil fertility. PMID:23127838

  8. Independent and additive effects of glutamic acid and methionine on yeast longevity.

    PubMed

    Wu, Ziyun; Song, Lixia; Liu, Shao Quan; Huang, Dejian

    2013-01-01

    It is established that glucose restriction extends yeast chronological and replicative lifespan, but little is known about the influence of amino acids on yeast lifespan, although some amino acids were reported to delay aging in rodents. Here we show that amino acid composition greatly alters yeast chronological lifespan. We found that non-essential amino acids (to yeast) methionine and glutamic acid had the most significant impact on yeast chronological lifespan extension, restriction of methionine and/or increase of glutamic acid led to longevity that was not the result of low acetic acid production and acidification in aging media. Remarkably, low methionine, high glutamic acid and glucose restriction additively and independently extended yeast lifespan, which could not be further extended by buffering the medium (pH 6.0). Our preliminary findings using yeasts with gene deletion demonstrate that glutamic acid addition, methionine and glucose restriction prompt yeast longevity through distinct mechanisms. This study may help to fill a gap in yeast model for the fast developing view that nutrient balance is a critical factor to extend lifespan. PMID:24244480

  9. Mechanistic investigation of the uncatalyzed esterification reaction of acetic acid and acid halides with methanol: a DFT study.

    PubMed

    Lawal, Monsurat M; Govender, Thavendran; Maguire, Glenn E M; Honarparvar, Bahareh; Kruger, Hendrik G

    2016-10-01

    Implementation of catalysts to drive reactions from reactants to products remains a burden to synthetic and organic chemists. In spite of investigations into the kinetics and mechanism of catalyzed esterification reactions, less effort has been made to explore the possibility of an uncatalyzed esterification process. Therefore, a comprehensive mechanistic perspective for the uncatalyzed mechanism at the molecular level is presented. Herein, we describe the non-catalyzed esterification reaction of acetic acid and its halide derivatives (XAc, where X= OH, F, Cl, Br, I) with methanol (MeOH) through a concerted process. The reaction in vacuum and methanol was performed using the density functional theory (DFT) method at M06-2X level with def2-TZVP basis set after a careful literature survey and computations. Esterification through cyclic 4- or 6-membered transition state structures in one- or two-step concerted mechanisms were investigated. The present study outlines the possible cyclic geometry conformations that may occur during experiments at simple ratio of reactants. The free energy of activation for acetic acid and acetyl chloride are 36 kcal mol(-1) and 21 kcal mol(-1), respectively. These are in good agreement with available experimental results from the literature. The selected quantum chemical descriptors proved to be useful tools in chemical reactivity prediction for the reaction mechanism. This quantum mechanics study can serve as a necessary step towards revisiting uncatalyzed reaction mechanisms in some classical organic reactions. PMID:27604278

  10. Acetic acid recovery from a hybrid biological-hydrothermal treatment process of sewage sludge - a pilot plant study.

    PubMed

    Andrews, J; Dare, P; Estcourt, G; Gapes, D; Lei, R; McDonald, B; Wijaya, N

    2015-01-01

    A two-stage process consisting of anaerobic fermentation followed by sub-critical wet oxidation was used to generate acetic acid from sewage sludge at pilot scale. Volatile fatty acids, dominated by propionic acid, were produced over 4-6 days in the 2,000 L fermentation reactor, which also achieved 31% solids reduction. Approximately 96% of the carbon was retained in solution over the fermentation stage. Using a 200 L wet oxidation reactor operating in batch mode, the second stage achieved 98% volatile suspended solids (VSS) destruction and 67% total chemical oxygen demand (tCOD) destruction. Acetic acid produced in this stage was recalcitrant to further degradation and was retained in solution. The gross yield from VSS was 16% for acetic acid and 21% for volatile fatty acids across the process, higher than reported yields for wet oxidation alone. The pilot plant results showed that 72% of the incoming phosphorus was retained in the solids, 94% of the nitrogen became concentrated in solution and 41% of the carbon was converted to a soluble state, in a more degradable form. Acetic acid produced from the process has the potential to be used to offset ethanol requirements in biological nutrient removal plants. PMID:25768220

  11. Ameyamaea chiangmaiensis gen. nov., sp. nov., an acetic acid bacterium in the alpha-Proteobacteria.

    PubMed

    Yukphan, Pattaraporn; Malimas, Taweesak; Muramatsu, Yuki; Takahashi, Mai; Kaneyasu, Mika; Potacharoen, Wanchern; Tanasupawat, Somboon; Nakagawa, Yasuyoshi; Hamana, Koei; Tahara, Yasutaka; Suzuki, Ken-ichiro; Tanticharoen, Morakot; Yamada, Yuzo

    2009-10-01

    Two isolates, AC04(T) and AC05, were isolated from the flowers of red ginger collected in Chiang Mai, Thailand. In phylogenetic trees based on 16S rRNA gene sequences, the two isolates were included within a lineage comprised of the genera Acidomonas, Gluconacetobacter, Asaia, Kozakia, Swaminathania, Neoasaia, Granulibacter, and Tanticharoenia, and they formed an independent cluster along with the type strain of Tanticharoenia sakaeratensis. The calculated pair-wise sequence similarities of isolate AC04(T) were 97.8-92.5% to the type strains of the type species of the 11 genera of acetic acid bacteria. The DNA base composition was 66.0-66.1 mol % G+C with a range of 0.1 mol %. A single-stranded, labeled DNA from isolate AC04(T) presented levels of DNA-DNA hybridization of 100, 85, 4, and 3% respectively to DNAs from isolates AC04(T) and AC05 and the type strains of Tanticharoenia sakaeratensis and Gluconacetobacter liquefaciens. The two isolates were unique morphologically in polar flagellation and physiologically in intense acetate oxidation to carbon dioxide and water and weak lactate oxidation. The intensity in acetate oxidation almost equaled that of the type strain of Acetobacter aceti. The two isolates had Q-10. Isolate AC04(T) was discriminated from the type strains of the type species of the 11 genera by 16S rRNA gene restriction analysis using restriction endonucleases TaqI and Hin6I. The unique phylogenetic, genetic, morphological, physiological, and biochemical characteristics obtained indicate that the two isolates can be classified into a separate genus, and Ameyamaea chiangmaiensis gen. nov., sp. nov. is proposed. The type strain is isolate AC04(T) (=BCC 15744(T), =NBRC 103196(T)), which has a DNA G+C content of 66.0 mol %. PMID:19809199

  12. Hydrogen production from steam reforming of acetic acid over Cu-Zn supported calcium aluminate.

    PubMed

    Mohanty, Pravakar; Patel, Madhumita; Pant, Kamal K

    2012-11-01

    Hydrogen can be produced by catalytic steam reforming (CSR) of biomass-derived oil. Typically bio oil contains 12-14% acetic acid; therefore, this acid was chosen as model compound for reforming of biooil with the help of a Cu-Zn/Ca-Al catalyst for high yield of H(2) with low CH(4) and CO content. Calcium aluminate support was prepared by solid-solid reaction at 1350°C. X-ray diffraction indicates 12CaO·7Al(2)O(3) as major, CaA(l4)O(7) and Ca(5)A(l6)O(14) as minor phases. Cu and Zn were loaded onto the support by wet-impregnation at 10 and 1wt.%, respectively. The catalysts were characterized by Brunauer-Emmett-Teller (BET), Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy TEM and the surface area for both support and Cu-Zn were 10.5 and 5.8m(2)/g, respectively. CSR was carried out in a tubular fixed bed reactor (I.D.=19mm) at temperatures between 600 and 800°C with 3-g loadings and (H(2)O/acetic acid) wt. ratio of 9:1. Significantly high (80%) yield of hydrogen was obtained over Cu-Zn/Ca-Al catalyst, as incorporation of Zn enhanced the H(2) yield by reducing deactivation of the catalyst. The coke formation on the support (Ca-12/Al-7) surface was negligible due to the presence of excess oxygen in the 12CaO·7Al(2)O(3) phase. PMID:22944490

  13. Staining of proteins in gels with Coomassie G-250 without organic solvent and acetic acid.

    PubMed

    Lawrence, Ann-Marie; Besir, H Uuml Seyin

    2009-01-01

    In classical protein staining protocols using Coomassie Brilliant Blue (CBB), solutions with high contents of toxic and flammable organic solvents (Methanol, Ethanol or 2-Propanol) and acetic acid are used for fixation, staining and destaining of proteins in a gel after SDS-PAGE. To speed up the procedure, heating the staining solution in the microwave oven for a short time is frequently used. This usually results in evaporation of toxic or hazardous Methanol, Ethanol or 2-Propanol and a strong smell of acetic acid in the lab which should be avoided due to safety considerations. In a protocol originally published in two patent applications by E.M. Wondrak (US2001046709 (A1), US6319720 (B1)), an alternative composition of the staining solution is described in which no organic solvent or acid is used. The CBB is dissolved in bidistilled water (60-80 mg of CBB G-250 per liter) and 35 mM HCl is added as the only other compound in the staining solution. The CBB staining of the gel is done after SDS-PAGE and thorough washing of the gel in bidistilled water. By heating the gel during the washing and staining steps, the process can be finished faster and no toxic or hazardous compounds are evaporating. The staining of proteins occurs already within 1 minute after heating the gel in staining solution and is fully developed after 15-30 min with a slightly blue background that is destained completely by prolonged washing of the stained gel in bidistilled water, without affecting the stained protein bands. PMID:19684570

  14. (+/-)-3-Oxocyclohexanecarboxylic and -acetic acids: contrasting hydrogen-bonding patterns in two homologous keto acids.

    PubMed

    Barcon, Alan; Brunskill, Andrew P J; Lalancette, Roger A; Thompson, Hugh W

    2002-03-01

    The crystal structures for the title compounds reveal fundamentally different hydrogen-bonding patterns. (+/-)-3-Oxocyclohexanecarboxylic acid, C(7)H(10)O(3), displays acid-to-ketone catemers having a glide relationship for successive components of the hydrogen-bonding chains which advance simultaneously by two cells in a and one in c [O...O = 2.683 (3) A and O-H...O = 166]. A pair of intermolecular close contacts exists involving the acid carbonyl group. The asymmetric unit in (+/-)-3-oxocyclohexaneacetic acid, C(8)H(12)O(3), utilizes only one of two available isoenthalpic conformers and its aggregation involves mutual hydrogen bonding by centrosymmetric carboxyl dimerization [O.O = 2.648 (3) A and O-H...O = 171]. Intermolecular close contacts exist for both the ketone and the acid carbonyl group. PMID:11870311

  15. Kozakia baliensis gen. nov., sp. nov., a novel acetic acid bacterium in the alpha-proteobacteria.

    PubMed

    Lisdiyanti, Puspita; Kawasaki, Hiroko; Widyastuti, Yantyati; Saono, Susono; Seki, Tatsuji; Yamada, Yuzo; Uchimura, Tai; Komagata, Kazuo

    2002-05-01

    Four bacterial strains were isolated from palm brown sugar and ragi collected in Bali and Yogyakarta, Indonesia, by an enrichment culture approach for acetic acid bacteria. Phylogenetic analysis based on 16S rRNA gene sequences showed that the four isolates constituted a cluster separate from the genera Acetobacter, Gluconobacter, Acidomonas, Gluconacetobacter and Asaia with a high bootstrap value in a phylogenetic tree. The isolates had high values of DNA-DNA similarity (78-100%) between one another and low values of the similarity (7-25%) to the type strains of Acetobacter aceti, Gluconobacter oxydans, Gluconacetobacter liquefaciens and Asaia bogorensis. The DNA base composition of the isolates ranged from 56.8 to 57.2 mol% G+C with a range of 0-4 mol%. The major quinone was Q-10. The isolates oxidized acetate and lactate to carbon dioxide and water, but the activity was weak, as with strains of Asaia bogorensis. The isolates differed from Asaia bogorensis strains in phenotypic characteristics. The name Kozakia baliensis gen. nov., sp. nov., is proposed for the four isolates. Strain Yo-3T (= NRIC 0488T = JCM 11301T = IFO 16664T = DSM 14400T) was isolated from palm brown sugar collected in Bali, Indonesia, and was designated as the type strain. PMID:12054243

  16. Butyric acid production from softwood hydrolysate by acetate-consuming Clostridium sp. S1 with high butyric acid yield and selectivity.

    PubMed

    Kim, Minsun; Kim, Ki-Yeon; Lee, Kyung Min; Youn, Sung Hun; Lee, Sun-Mi; Woo, Han Min; Oh, Min-Kyu; Um, Youngsoon

    2016-10-01

    The aim of this work was to study the butyric acid production from softwood hydrolysate by acetate-consuming Clostridium sp. S1. Results showed that Clostridium sp. S1 produced butyric acid by simultaneously utilizing glucose and mannose in softwood hydrolysate and, more remarkably, it consumed acetic acid in hydrolysate. Clostridium sp. S1 utilized each of glucose, mannose, and xylose as well as mixed sugars simultaneously with partially repressed xylose utilization. When softwood (Japanese larch) hydrolysate containing glucose and mannose as the main sugars was used, Clostridium sp. S1 produced 21.17g/L butyric acid with the yield of 0.47g/g sugar and the selectivity of 1 (g butyric acid/g total acids) owing to the consumption of acetic acid in hydrolysate. The results demonstrate potential of Clostridium sp. S1 to produce butyric acid selectively and effectively from hydrolysate not only by utilizing mixed sugars simultaneously but also by converting acetic acid to butyric acid. PMID:27474955

  17. Translocation of radiolabeled indole-3-acetic acid and indole-3-acetyl-myo-inositol from kernel to shoot of Zea mays L

    NASA Technical Reports Server (NTRS)

    Chisnell, J. R.; Bandurski, R. S.

    1988-01-01

    Either 5-[3H]indole-3-acetic acid (IAA) or 5-[3H]indole-3-acetyl-myo-inositol was applied to the endosperm of kernels of dark-grown Zea mays seedlings. The distribution of total radioactivity, radiolabeled indole-3-acetic acid, and radiolabeled ester conjugated indole-3-acetic acid, in the shoots was then determined. Differences were found in the distribution and chemical form of the radiolabeled indole-3-acetic acid in the shoot depending upon whether 5-[3H]indole-3-acetic acid or 5-[3H]indole-3-acetyl-myo-inositol was applied to the endosperm. We demonstrated that indole-3-acetyl-myo-inositol applied to the endosperm provides both free and ester conjugated indole-3-acetic acid to the mesocotyl and coleoptile. Free indole-3-acetic acid applied to the endosperm supplies some of the indole-3-acetic acid in the mesocotyl but essentially no indole-3-acetic acid to the coleoptile or primary leaves. It is concluded that free IAA from the endosperm is not a source of IAA for the coleoptile. Neither radioactive indole-3-acetyl-myo-inositol nor IAA accumulates in the tip of the coleoptile or the mesocotyl node and thus these studies do not explain how the coleoptile tip controls the amount of IAA in the shoot.

  18. Green acetylation of solketal and glycerol formal by heterogeneous acid catalysts to form a biodiesel fuel additive.

    PubMed

    Dodson, Jennifer R; Leite, Thays d C M; Pontes, Nathália S; Peres Pinto, Bianca; Mota, Claudio J A

    2014-09-01

    A glut of glycerol has formed from the increased production of biodiesel, with the potential to integrate the supply chain by using glycerol additives to improve biodiesel properties. Acetylated acetals show interesting cold flow and viscosity effects. Herein, a solventless heterogeneously catalyzed process for the acetylation of both solketal and glycerol formal to new products is demonstrated. The process is optimized by studying the effect of acetylating reagent (acetic acid and acetic anhydride), reagent molar ratios, and a variety of commercial solid acid catalysts (Amberlyst-15, zeolite Beta, K-10 Montmorillonite, and niobium phosphate) on the conversion and selectivities. High conversions (72-95%) and selectivities (86-99%) to the desired products results from using acetic anhydride as the acetylation reagent and a 1:1 molar ratio with all catalysts. Overall, there is a complex interplay between the solid catalyst, reagent ratio, and acetylating agent on the conversion, selectivities, and byproducts formed. The variations are discussed and explained in terms of reactivity, thermodynamics, and reaction mechanisms. An alternative and efficient approach to the formation of 100% triacetin involves the ring-opening, acid-catalyzed acetylation from solketal or glycerol formal with excesses of acetic anhydride. PMID:25045049

  19. Effect of marine mangrove Avicennia marina (Forssk.) Vierh against acetic acid-induced ulcerative colitis in experimental mice.

    PubMed

    Rise, C L Victoria; Prabhu, V Vinod; Guruvayoorappan, Chandrasekharan

    2012-01-01

    Ulcerative colitis and Crohn's disease are two conditions that have many features in common and are referred as inflammatory bowel disease (IBD). Patients with IBD are predisposed to colorectal cancer. This investigation evaluates the effect of marine mangrove Avicennia marina against acetic acid-induced colitis. The treatment of A marina extract significantly decreased the colonic lipid peroxides, glutathione peroxidase, and serum nitric oxide and significantly increased the colonic and erythrocyte superoxide dismutase and glutathione levels compared with colitis control. In addition, A marina extract significantly decreased the lesion score and wet colon weight compared with colitis control. Treatment with A marina extract reflects its therapeutic activity against UC by minimal damage of colonic epithelial cells compared with colitis control during histopathologic examination. These protective role of A marina extract against UC could be attributed to the presence of higher levels of decanoic acid, diethylhydroxylamine (DEHA), pentanoic acid, pyrrolidine, 4-chlorophenyl, thiazolidinones, and arabinopyranoside (flavonoid). These findings suggest that A marina extract could be useful as a potential (natural) therapeutic agent for IBD. PMID:23216642

  20. Isotopic composition of Murchison organic compounds: Intramolecular carbon isotope fractionation of acetic acid. Simulation studies of cosmochemical organic syntheses

    NASA Technical Reports Server (NTRS)

    Yuen, G. U.; Cronin, J. R.; Blair, N. E.; Desmarais, D. J.; Chang, S.

    1991-01-01

    Recently, in our laboratories, samples of Murchison acetic acid were decarboxylated successfully and the carbon isotopic composition was measured for the methane released by this procedure. These analyses showed significant differences in C-13/C-12 ratios for the methyl and carboxyl carbons of the acetic acid molecule, strongly suggesting that more than one carbon source may be involved in the synthesis of the Murchison organic compounds. On the basis of this finding, laboratory model systems simulating cosmochemical synthesis are being studied, especially those processes capable of involving two or more starting carbon sources.

  1. Treatment of Myositis Ossificans with acetic acid phonophoresis: a case series

    PubMed Central

    Bagnulo, Angela; Gringmuth, Robert

    2014-01-01

    Objective To create awareness of myositis ossificans (MO) as a potential complication of muscle contusion by presenting its clinical presentation and diagnostic features. An effective method of treatment is offered for those patients who develop traumatic MO. Management: Patients in this case series developed traumatic MO, confirmed on diagnostic ultrasound. Patients participated in a treatment regimen consisting of phonophoresis of acetic acid with ultrasound. Outcome: In all cases, a trial of phonophoresis therapy significantly decreased patient signs, symptoms and the size of the calcification on diagnostic ultrasound in most at a 4-week post diagnosis mark. Discussion: Due to the potential damage to the muscle and its function, that surgical excision carries; safe effective methods of conservative treatment for MO are crucial. MO deserves more attention in the literature due to its common presentation in athletes. PMID:25550659

  2. Identification and biochemical characterization of an Arabidopsis indole-3-acetic acid glucosyltransferase.

    PubMed

    Jackson, R G; Lim, E K; Li, Y; Kowalczyk, M; Sandberg, G; Hoggett, J; Ashford, D A; Bowles, D J

    2001-02-01

    Biochemical characterization of recombinant gene products following a phylogenetic analysis of the UDP-glucosyltransferase (UGT) multigene family of Arabidopsis has identified one enzyme (UGT84B1) with high activity toward the plant hormone indole-3-acetic acid (IAA) and three related enzymes (UGT84B2, UGT75B1, and UGT75B2) with trace activities. The identity of the IAA conjugate has been confirmed to be 1-O-indole acetyl glucose ester. A sequence annotated as a UDP-glucose:IAA glucosyltransferase (IAA-UGT) in the Arabidopsis genome and expressed sequence tag data bases given its similarity to the maize iaglu gene sequence showed no activity toward IAA. This study describes the first biochemical analysis of a recombinant IAA-UGT and provides the foundation for future genetic approaches to understand the role of 1-O-indole acetyl glucose ester in Arabidopsis. PMID:11042207

  3. Indole-3-acetic acid: A widespread physiological code in interactions of fungi with other organisms

    PubMed Central

    Fu, Shih-Feng; Wei, Jyuan-Yu; Chen, Hung-Wei; Liu, Yen-Yu; Lu, Hsueh-Yu; Chou, Jui-Yu

    2015-01-01

    Plants as well as microorganisms, including bacteria and fungi, produce indole-3-acetic acid (IAA). IAA is the most common plant hormone of the auxin class and it regulates various aspects of plant growth and development. Thus, research is underway globally to exploit the potential for developing IAA-producing fungi for promoting plant growth and protection for sustainable agriculture. Phylogenetic evidence suggests that IAA biosynthesis evolved independently in bacteria, microalgae, fungi, and plants. Present studies show that IAA regulates the physiological response and gene expression in these microorganisms. The convergent evolution of IAA production leads to the hypothesis that natural selection might have favored IAA as a widespread physiological code in these microorganisms and their interactions. We summarize recent studies of IAA biosynthetic pathways and discuss the role of IAA in fungal ecology. PMID:26179718

  4. [The laterally spreading colon tumors. Diagnostic efficacy of colonoscopy and chromoscopy using indigocarmine and acetic acid].

    PubMed

    Iakovenko, V O; Kuryk, O H

    2013-11-01

    The laterally spreading colon tumors (LST) constitute a kind of flat superficial neoplasia, which may cause colorectal cancer. There was studied the efficacy of colonoscopy and chromoscopy, using indigocarmine and acetic acid in the LST diagnosis in 897 patients. In 85 (9.5%) patients, suffering adenoma 113 LST were revealed, including 84 (74.3%) of a nongranular type (LST - NG), 29 (25.7%)--of granular type (LST - G). The diameter of LST was from 10 to 120 mm, 19.6 mm at average. Tubular adenoma was diagnosed in 67 (59%) observations, the dentate one--in 24 (21%), papillary--in 12 (11%), papillary-tubular--in 10 (9%). PMID:24501982

  5. Vapor phase ketonization of acetic acid on ceria based metal oxides

    SciTech Connect

    Liu, Changjun; Karim, Ayman M.; Lebarbier, Vanessa MC; Mei, Donghai; Wang, Yong

    2013-12-01

    The activities of CeO2, Mn2O3-CeO2 and ZrO2-CeO2 were measured for acetic acid ketonization under reaction conditions relevant to pyrolysis vapor upgrading. We show that the catalyst ranking changed depending on the reaction conditions. Mn2O3-CeO2 was the most active catalyst at 350 oC, while ZrO2 - CeO2 was the most active catalyst at 450 oC. Under high CO2 and steam concentration in the reactants, Mn2O3-CeO2 was the most active catalyst at 350 and 450 °C. The binding energies of steam and CO2 with the active phase were calculated to provide the insight into the tolerance of Mn2O3-CeO2 to steam and CO2.

  6. Acetic Acid Bacteria Genomes Reveal Functional Traits for Adaptation to Life in Insect Guts

    PubMed Central

    Chouaia, Bessem; Gaiarsa, Stefano; Crotti, Elena; Comandatore, Francesco; Degli Esposti, Mauro; Ricci, Irene; Alma, Alberto; Favia, Guido; Bandi, Claudio; Daffonchio, Daniele

    2014-01-01

    Acetic acid bacteria (AAB) live in sugar rich environments, including food matrices, plant tissues, and the gut of sugar-feeding insects. By comparing the newly sequenced genomes of Asaia platycodi and Saccharibacter sp., symbionts of Anopheles stephensi and Apis mellifera, respectively, with those of 14 other AAB, we provide a genomic view of the evolutionary pattern of this bacterial group and clues on traits that explain the success of AAB as insect symbionts. A specific pre-adaptive trait, cytochrome bo3 ubiquinol oxidase, appears ancestral in AAB and shows a phylogeny that is congruent with that of the genomes. The functional properties of this terminal oxidase might have allowed AAB to adapt to the diverse oxygen levels of arthropod guts. PMID:24682158

  7. Utilization of Vinegar for Isolation of Cellulose Producing Acetic Acid Bacteria

    NASA Astrophysics Data System (ADS)

    Aydin, Y. Andelib; Aksoy, Nuran Deveci

    2010-06-01

    Wastes of traditionally fermented Turkish vinegar were used in the isolation of cellulose producing acetic acid bacteria. Waste material was pre-enriched in Hestrin-Schramm medium and microorganisms were isolated by plating dilution series on HS agar plates The isolated strains were subjected to elaborate biochemical and physiological tests for identification. Test results were compared to those of reference strains Gluconacetobacter xylinus DSM 46604, Gluconacetobacter hansenii DSM 5602 and Gluconacetobacter liquefaciens DSM 5603. Seventeen strains, out of which only three were found to secrete the exopolysaccharide cellulose. The highest cellulose yield was recorded as 0.263±0.02 g cellulose L-1 for the strain AS14 which resembled Gluconacetobacter hansenii in terms of biochemical tests.

  8. Utilization of Vinegar for Isolation of Cellulose Producing Acetic Acid Bacteria

    SciTech Connect

    Aydin, Y. Andelib; Aksoy, Nuran Deveci

    2010-06-17

    Wastes of traditionally fermented Turkish vinegar were used in the isolation of cellulose producing acetic acid bacteria. Waste material was pre-enriched in Hestrin-Schramm medium and microorganisms were isolated by plating dilution series on HS agar plates The isolated strains were subjected to elaborate biochemical and physiological tests for identification. Test results were compared to those of reference strains Gluconacetobacter xylinus DSM 46604, Gluconacetobacter hansenii DSM 5602 and Gluconacetobacter liquefaciens DSM 5603. Seventeen strains, out of which only three were found to secrete the exopolysaccharide cellulose. The highest cellulose yield was recorded as 0.263+-0.02 g cellulose L{sup -1} for the strain AS14 which resembled Gluconacetobacter hansenii in terms of biochemical tests.

  9. Study of dynamic process of acetic acid induced-whitening in epithelial tissues at cellular level

    NASA Astrophysics Data System (ADS)

    Wu, Tao T.; Qu, Jianan Y.; Cheung, Tak Hong; Yim, So Fan; Wong, Yick Fu

    2005-06-01

    Acetic acid, inducing transient whitening (acetowhitening) when applied to epithelial tissues, is a commonly used contrast agent for detecting early cervical cancer. The goals of this research are to investigate the temporal characteristics of acetowhitening process in cervical epithelial tissue at cellular level and develop a clear understanding of the diagnostic information carried in the acetowhitening signal. A system measuring time-resolved reflectance was built to study the rising and decay processes of acetowhitening signal from the monolayered cell cultures of normal and cancerous cervical squamous cells. It is found that the dynamic processes of acetowhitening in normal and cancerous cells are significantly different. The results of this study provide insight valuable to further understand the acetowhitening process in epithelial cells and to encourage the development of an objective procedure to detect the early cervical cancers based on quantitative monitoring of the dynamic process of acetowhitening

  10. Ultrastructure of Sheep Primordial Follicles Cultured in the Presence of Indol Acetic Acid, EGF, and FSH

    PubMed Central

    Andrade, Evelyn Rabelo; Maddox-Hyttel, Poul; Landim-Alvarenga, Fernanda Da Cruz; Viana Silva, José Roberto; Alfieri, Amauri Alcindo; Seneda, Marcelo Marcondes; Figueiredo, José Ricardo; Toniolli, Ricardo

    2011-01-01

    The aim of this study was to investigate the ultrastructural characteristics of primordial follicles after culturing of sheep ovarian cortical slices in the presence of indol acetic acid (IAA), Epidermal Growth Factor (EGF), and FSH. To evaluate ultrastructure of primordial follicles cultured in MEM (control) or in MEM containing IAA, EGF, and FSH, fragments of cultured tissue were processes for transmission electron microscopy. Except in the control, primordial follicles cultured in supplemented media for 6 d were ultrastructurally normal. They had oocyte with intact nucleus and the cytoplasm contained heterogeneous-sized lipid droplets and numerous round or elongated mitochondria with intact parallel cristae were observed. Rough endoplasmic reticulum (RER) was rarely found. The granulosa cells cytoplasm contained a great number of mitochondria and abundant RER. In conclusion, the presence of IAA, EGF, and FSH helped to maintain ultrastructural integrity of sheep primordial follicles cultured in vitro. PMID:21188166

  11. Mathematical model for liquid-gas equilibrium in acetic acid fermentations

    PubMed

    Romero; Cantero

    1998-08-01

    An experimental study was conducted to propose an adequate mathematical model for liquid-gas equilibrium in acetic acid fermentations. Three operation scales (laboratory, pilot plant, and industrial plant) were employed to obtain the sets of experimental data. The proposed model, based in the UNIFAC method for the estimation of activity coefficients of a solution consisting of several components, takes into account the effect of temperature. However, in the set of equations, it has been necessary to put in the degree of equilibrium (epsilon). This coefficient adequately reflects the physical conditions of fermentation equipment. The experimental and numerical results help to define the fundamental mechanisms for liquid-gas equilibrium in these systems and demonstrate the model validity in the three tested scales. It was also found that in an industrial setting, closed systems are those with lowest evaporation losses. Copyright 1998 John Wiley & Sons, Inc. PMID:10099342

  12. Contribution of acetic acid to the hydrolysis of lignocellulosic biomass under abiotic conditions.

    PubMed

    Trzcinski, Antoine P; Stuckey, David C

    2015-06-01

    Acetic acid was used in abiotic experiments to adjust the solution pH and investigate its influence on the chemical hydrolysis of the Organic Fraction of Municipal Solid Waste (OFMSW). Soluble chemical oxygen demand (SCOD) was used to measure the hydrolysis under oxidative conditions (positive oxidation-reduction potential values), and pH 4 allowed for 20% (±2%) of the COD added to be solubilized, whereas only 12% (±1%) was solubilized at pH7. Under reducing conditions (negative oxidation-reduction potential values) and pH 4, 32.3% (±3%) of the OFMSW was solubilized which shows that acidogenesis at pH 4 during the anaerobic digestion of solid waste can result in chemical hydrolysis. In comparison, bacterial hydrolysis resulted in 54% (±6%) solubilization. PMID:25794810

  13. Characterization of a bioflocculant produced by Citrobacter sp. TKF04 from acetic and propionic acids.

    PubMed

    Fujita, M; Ike, M; Tachibana, S; Kitada, G; Kim, S M; Inoue, Z

    2000-01-01

    A bacterial strain, TKF04, capable of producing a bioflocculant from acetic and/or propionic acids was isolated from a biofilm formed in inside a kitchen drain. It was identified as a Citrobacter based on its morphological and physiological characteristics and the partial sequences of its 16S rRNA. TKF04 produced the bioflocculant during the logarithmic phase of growth, and the optimum temperature and pH for the bioflocculant production were 30 degrees C and 7.2-10.0, respectively. It could utilize some organic acids and sugars for its growth as the sole carbon sources when yeast extract was supplemented; however, only acetate and propionate were found to be good substrates for the bioflocculant production. The crude bioflocculant could be recovered from the supernatant of the culture broth by ethanol precipitation and dialysis against deionized water. It was found to be effective for flocculation of a kaolin suspension, when added at a final concentration of 1-10 mg/l, over a wide range of pHs (2-8) and temperatures (approximately 3-95 degrees C), while the co-presence of cations (Na+, K+, Ca2+, Mg2+, Fe2+, Al3+ or Fe3+) did not enhance the flocculating activity. It could efficiently flocculate a variety of inorganic and organic suspended particles, including kaolin, diatomite, bentonite, activated carbon, soil and activated sludge. It contained glucosamine as the major component, and the molecular weight was estimated to be between 232 and 440 kDa by gel filtration. The observation that the flocculating activity was completely lost following chitinase treatment and its analysis with a Fourier transform infrared spectrometer suggested that the bioflocculant is a biopolymer structurally-similar to chitin or chitosan. PMID:16232696

  14. Pickled egg production: effect of brine acetic acid concentration and packing conditions on acidification rate.

    PubMed

    Acosta, Oscar; Gao, Xiaofan; Sullivan, Elizabeth K; Padilla-Zakour, Olga I

    2014-05-01

    U.S. federal regulations require that acidified foods must reach a pH of 4.6 or lower within 24 h of packaging or be kept refrigerated until then. Processes and formulations should be designed to satisfy this requirement, unless proper studies demonstrate the safety of other conditions. Our objective was to determine the effect of brine acetic acid concentration and packing conditions on the acidification rate of hard-boiled eggs. Eggs were acidified (60/40 egg-to-brine ratio) at various conditions of brine temperature, heat treatment to filled jars, and postpacking temperature: (i) 25 °C/none/25 °C (cold fill), (ii) 25 °C/none/2 °C (cold fill/refrigerated), (iii) 85 °C/none/25 °C (hot fill), and (iv) 25 °C/100 °C for 16 min/25 °C (water bath). Three brine concentrations were evaluated (7.5, 4.9, and 2.5% acetic acid) and egg pH values (whole, yolk, four points within egg) were measured from 4 to 144 h, with eggs equilibrating at pH 3.8, 4.0, and 4.3, respectively. Experiments were conducted in triplicate, and effects were considered significant when P < 0.05. Multiple linear regression analysis was conducted to evaluate the effect on pH values at the center of the yolk. Regression analysis showed that brine concentration of 2.5% decreased the acidification rate, while packing conditions of the hot fill trial increased it. Inverse prediction was used to determine the time for the center of the yolk and the total yolk to reach a pH value of 4.6. These results demonstrate the importance of conducting acidification studies with proper pH measurements to determine safe conditions to manufacture commercially stable pickled eggs. PMID:24780334

  15. Tryptophan regulates thaxtomin A and indole-3-acetic acid production in Streptomyces scabiei and modifies its interactions with radish seedlings.

    PubMed

    Legault, Geneviève S; Lerat, Sylvain; Nicolas, Philippe; Beaulieu, Carole

    2011-09-01

    The virulence of Streptomyces scabiei, the causal agent of common scab, depends mainly on the production of the toxin thaxtomin A. S. scabiei also produces indole-3-acetic acid (IAA) but the role of this hormone in the interaction between pathogenic streptomycetes and plants has not yet been elucidated. Tryptophan is a biosynthetic precursor of both IAA and thaxtomin A. In this study, the effect of tryptophan on thaxtomin A and IAA production as well as its effect on the transcription of the corresponding biosynthetic genes in S. scabiei has been analyzed. In vitro IAA production depended on the availability of tryptophan. However, addition of this amino acid to the culture medium inhibited the biosynthesis of thaxtomin A. Expression of thaxtomin A biosynthetic genes nos and txtA were strongly repressed in the presence of tryptophan; however, modulation of the expression was not observed for the IAA biosynthetic genes iaaM and iaaH. The effects of an exogenous tryptophan supply on S. scabiei virulence were assessed on radish seedlings. Addition of tryptophan reduced symptoms on inoculated radish roots compared with seedlings grown in the absence of the bacterium, by way of inhibition of thaxtomin A production and increase of IAA biosynthesis. PMID:21521002

  16. Bacterial dynamics and metabolite changes in solid-state acetic acid fermentation of Shanxi aged vinegar.

    PubMed

    Li, Sha; Li, Pan; Liu, Xiong; Luo, Lixin; Lin, Weifeng

    2016-05-01

    Solid-state acetic acid fermentation (AAF), a natural or semi-controlled fermentation process driven by reproducible microbial communities, is an important technique to produce traditional Chinese cereal vinegars. Highly complex microbial communities and metabolites are involved in traditional Chinese solid-state AAF, but the association between microbiota and metabolites during this process are still poorly understood. In this study, we performed amplicon 16S rRNA gene sequencing on the Illumina MiSeq platform, PCR-denaturing gradient gel electrophoresis, and metabolite analysis to trace the bacterial dynamics and metabolite changes under AAF process. A succession of bacterial assemblages was observed during the AAF process. Lactobacillales dominated all the stages. However, Acetobacter species in Rhodospirillales were considerably accelerated during AAF until the end of fermentation. Quantitative PCR results indicated that the biomass of total bacteria showed a "system microbe self-domestication" process in the first 3 days, and then peaked at the seventh day before gradually decreasing until the end of AAF. Moreover, a total of 88 metabolites, including 8 organic acids, 16 free amino acids, and 66 aroma compounds were detected during AAF. Principal component analysis and cluster analyses revealed the high correlation between the dynamics of bacterial community and metabolites. PMID:26754813

  17. Monitoring Subsurface Microbial Biomass, Community Composition and Physiological Status during Biological Uranium Reduction with Acetate Addition using Lipid Analysis, DNA Arrays and q-PCR

    NASA Astrophysics Data System (ADS)

    Peacock, A. D.; Long, P. E.; N'Guessan, L.; Williams, K. H.; Chandler, D.

    2011-12-01

    Our objectives for this effort were to investigate microbial community dynamics during each of the distinct terminal electron accepting phases that occur during long-term acetate addition for the immobilization of Uranium. Groundwater was collected from four wells (one up gradient and three down gradient) at three different depths and at four different times (pre-acetate injection, peak iron reduction, iron/sulfate reduction transition and during heavy sulfate reduction). Phospholipid fatty acid analysis (PLFA) results from ground water showed that microbial biomass was highest during Iron reduction and then lower during the transition from Iron reduction to Sulfate reduction and lowest during Sulfate reduction. Microbial community composition parameters as measured by PLFA showed distinct differences with terminal electron accepting status. Monounsaturated PLFA that have been shown to correspond with Gram-negative bacteria and Geobacteracea increased markedly with Iron reduction and then decreased with the onset of sulfate reduction. Bacterial physiological stress levels as measured by PLFA fluctuated with terminal electron acceptor status. Low bacterial stress levels coincided with pre-donor addition and Iron reduction but were much higher during Iron to Sulfate transition and during Sulfate reduction. Microarray results showed the expected progression of microbial signatures from Iron to Sulfate -reducers with changes in acetate amendment and in situ field conditions. The microarray response for Geobacter was highly correlated with qPCR for the same target gene (R2 = 0.84). Probes targeting Desulfobacter and Desulfitobacterium were the most reactive during the Iron to Sulfate transition and into Sulfate reduction, with a consistent Desulfotomaculum signature throughout the field experiment and a general decrease in Geobacter signal to noise ratios during the onset of Sulfate reducing conditions. Nitrate reducers represented by Dechloromonas and Dechlorosoma

  18. Evaluation of the tolerance of acetic acid and 2-furaldehyde on the growth of Pichia stipitis and its respiratory deficient.

    PubMed

    Ortiz-Muñiz, B; Rasgado-Mellado, J; Solis-Pacheco, J; Nolasco-Hipólito, C; Domínguez-González, J M; Aguilar-Uscanga, M G

    2014-10-01

    The use of lignocellulosic residues for ethanol production is limited by toxic compounds in fermenting yeasts present in diluted acid hydrolysates like acetic acid and 2-furaldehyde. The respiratory deficient phenotype gives the cell the ability to resist several toxic compounds. So the aim of this work was to evaluate the tolerance to toxic compounds present in lignocellulosic hydrolysates like acetic acid and 2-furaldehyde in Pichia stipitis and its respiratory deficient strains. The respiratory deficient phenotype was induced by exposure to chemical agents such as acriflavine, acrylamide and rhodamine; 23 strains were obtained. The selection criterion was based on increasing specific ethanol yield (g ethanol g(-1) biomass) with acetic acid and furaldehyde tolerance. The screening showed that P. stipitis NRRL Y-7124 ACL 2-1RD (lacking cytochrome c), obtained using acrylamide, presented the highest specific ethanol production rate (1.82 g g(-1 )h(-1)). Meanwhile, the ACF8-3RD strain showed the highest acetic acid tolerance (7.80 g L(-1)) and the RHO2-3RD strain was able to tolerate up to 1.5 g L(-1) 2-furaldehyde with a growth and ethanol production inhibition of 23 and 22 %, respectively. The use of respiratory deficient yeast phenotype is a strategy for ethanol production improvement in a medium with toxic compounds such as hydrolysed sugarcane bagasse amongst others. PMID:24700134

  19. ANTIFUNGAL AND SPROUT REGULATORY BIOACTIVITIES OF PHENYLACETIC ACID, INDOLE-3-ACETIC ACID, AND TYROSOL ISOLATED FROM THE POTATO DRY ROT SUPPRESSIVE BACTERIUM ENTEROBACTER CLOACAE S11:T:07

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Enterobacter cloacae S11:T:07 (NRRL B-21050) is a promising biological control agent which has significantly reduced both fungal dry rot disease and sprouting in lab and pilot potato storages. The metabolites phenylacetic acid (PAA), indole-3-acetic acid (IAA), and tyrosol (TSL) were isolated from ...

  20. Influence of phenolic acids on indole acetic acid production and on the type III secretion system gene transcription in food-associated Pseudomonas fluorescens KM05.

    PubMed

    Myszka, Kamila; Schmidt, Marcin T; Olejnik-Schmidt, Agnieszka K; Leja, Katarzyna; Czaczyk, Katarzyna

    2014-12-01

    The purpose of these investigations was to evaluate the reduction capability of phenolic acids (ferulic, chlorogenic, gallic, and p-coumaric acids) on indole acetic acid synthesis by food-associated Pseudomonas fluorescens KM05. Specific genetic primer for the type III secretion system (TTSS) in P. fluorescens KM05 was designed and the influence of phenolic acids on its expression was investigated. In the work the ferulic and chlorogenic acids at the concentration of 0.02 and 0.04 μg/ml affected on bacterial growth pattern and the signal molecules production. The phenolic acids, that were appreciable effective against P. fluorescens KM05 indole acetic acid production, significantly suppressed TTSS gene. PMID:24994472

  1. Short-term fumigation of honey bee (Hymenoptera: Apidae) colonies with formic and acetic acids for the control of Varroa destructor (Acari: Varroidae).

    PubMed

    vanEngelsdorp, Dennis; Underwood, Robyn M; Cox-Foster, Diana L

    2008-04-01

    Controlling populations of varroa mites is crucial for the survival of the beekeeping industry. Many treatments exist, and all are designed to kill mites on adult bees. Because the majority of mites are found under capped brood, most treatments are designed to deliver active ingredients over an extended period to control mites on adult bees, as developing bees and mites emerge. In this study, a 17-h application of 50% formic acid effectively killed mites in capped worker brood and on adult bees without harming queens or uncapped brood. Neither acetic acid nor a combined treatment of formic and acetic acids applied to the West Virginia formic acid fumigator was as effective as formic acid alone in controlling varroa mites. In addition, none of the treatments tested in late summer had an effect on the late-season prevalence of deformed wing virus. The short-term formic acid treatment killed > 60% of varroa mites in capped worker brood; thus, it is a promising tool for beekeepers, especially when such treatments are necessary during the nectar flow. PMID:18459386

  2. Improved Monitoring of Female Codling Moth (Lepidoptera: Tortricidae) with Pear Ester Plus Acetic Acid in Sex Pheromone-treated Orchards

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Catch of codling moth, Cydia pomonella (L.), in clear delta traps baited with ethyl (E,Z)-2,4-decadienoate (pear ester, PE) and acetic acid (AA) in separate lures (PE+AA) was compared with catch in orange delta traps baited with a single lure containing PE and the sex pheromone, (E,E)-8,10-dodecadie...

  3. ETHANOL, ACETIC ACID, AND WATER ADSORPTION FROM BINARY AND TERNARY LIQUID MIXTURES ON HIGH-SILICA ZEOLITES

    EPA Science Inventory

    Adsorption isotherms were measured for ethanol, acetic acid, and water adsorbed on high-silica ZSM-5 zeolite powder from binary and ternary liquid mixtures at room temperature. Ethanol and water adsorption on two high-silica ZSM-5 zeolites with different aluminum contents and a h...

  4. 40 CFR 721.10074 - Acetic acid, 2-chloro-, 1-(3,3-dimethylcyclohexyl)ethyl ester.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... acetic acid, 2-chloro-, 1-(3,3-dimethylcyclohexyl)ethyl ester (PMN P-05-568; CAS No. 477218-59-0) is.... Requirements as specified in § 721.80(h). (ii) (b) Specific requirements. The provisions of subpart A of this... (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses...

  5. 40 CFR 721.10074 - Acetic acid, 2-chloro-, 1-(3,3-dimethylcyclohexyl)ethyl ester.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... acetic acid, 2-chloro-, 1-(3,3-dimethylcyclohexyl)ethyl ester (PMN P-05-568; CAS No. 477218-59-0) is.... Requirements as specified in § 721.80(h). (ii) (b) Specific requirements. The provisions of subpart A of this... (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses...

  6. Acetyl xylan esterase of Aspergillus ficcum catalyzed the synthesis of peracetic acid from ethyl acetate and hydrogen peroxide.

    PubMed

    Park, Seung-Moon

    2011-11-01

    Recombinant acetyl xylan esterase (rAXE) of Aspergillus ficcum catalyzed the synthesis of peracetic acid (PAA) from ethyl acetate and hydrogen peroxide. Ten micrograms of rAXE catalyzed the synthesis of 1.34 mM of PAA, which can be used for the pretreatment of cellulosic biomass in situ. PMID:21824816

  7. Production of acetic acid by hydrothermal two-step process of vegetable wastes for use as a road deicer

    NASA Astrophysics Data System (ADS)

    Jin, F.; Watanabe, Y.; Kishita, A.; Enomoto, H.; Kishida, H.

    2008-07-01

    This study aimed to produce acetic acid from vegetable wastes by a new hydrothermal two-step process. A continuous flow reaction system with a maximum treatment capacity of 2 kg/h of dry biomass developed by us was used. Five kinds of vegetables of carrots, white radish, chinese cabbage, cabbage and potato were selected as the representation of vegetable wastes. First, batch experiments with the selected vegetables were performed under the condition of 300°C, 1 min for the first step, and 300°C, 1 min and 70% oxygen supply for the second step, which is the optimum condition for producing acetic acid in the case of using starch as test material. The highest yields of acetic acid from five vegetables were almost the same as those obtained from starch. Subsequently, similar the highest yield of acetic acid and experimental conditions from vegetables were also obtained successfully using the continuous flow reaction system. These results should be useful for developing an industrial scale process.

  8. Integrated phospholipidomics and transcriptomics analysis of Saccharomyces cerevisiae with enhanced tolerance to a mixture of acetic acid, furfural, and phenol

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A mixture of acetic acid, furfural and phenol (AFP), three representative lignocellulose derived inhibitors, significantly inhibited the growth and bioethanol production of Saccharomyces cerevisiae. In order to uncover mechanisms behind the enhanced tolerance of an inhibitor-tolerant S.cerevisiae s...

  9. INHIBITION OF NEURAL CREST CELL MIGRATION BY THE WATER DISINFECTION BYPRODUCTS DICHLORO-, DIBROMO-, AND BROMOCHLORO-ACETIC ACID.

    EPA Science Inventory

    INHIBITION OF NEURAL CREST CELL MIGRATION BY THE WATER DISINFECTION BYPRODUCTS DICHLORO-, DIBROMO- AND BROMOCHLORO-ACETIC ACID. JE Andrews, H Nichols, J Schmid 1, and ES Hunter. Reproductive Toxicology Division, 1Research Support Division, NHEERL, USEPA, RTP, NC, USA.

    ...

  10. Formic and Acetic Acids in Degradation Products of Plant Volatiles Elicit Olfactory and Behavioral Responses from an Insect Vector.

    PubMed

    George, Justin; Robbins, Paul S; Alessandro, Rocco T; Stelinski, Lukasz L; Lapointe, Stephen L

    2016-05-01

    Volatile phytochemicals play a role in orientation by phytophagous insects. We studied antennal and behavioral responses of the Asian citrus psyllid, Diaphorina citri, vector of the citrus greening disease pathogen. Little or no response to citrus leaf volatiles was detected by electroantennography. Glass cartridges prepared with β-ocimene or citral produced no response initially but became stimulatory after several days. Both compounds degraded completely in air to a number of smaller molecules. Two peaks elicited large antennal responses and were identified as acetic and formic acids. Probing by D. citri of a wax substrate containing odorants was significantly increased by a blend of formic and acetic acids compared with either compound separately or blends containing β-ocimene and/or citral. Response surface modeling based on a 4-component mixture design and a 2-component mixture-amount design predicted an optimal probing response on wax substrate containing a blend of formic and acetic acids. Our study suggests that formic and acetic acids play a role in host selection by D. citri and perhaps by phytophagous insects in general even when parent compounds from which they are derived are not active. These results have implications for the investigation of arthropod olfaction and may lead to elaboration of attract-and-kill formulations to reduce nontarget effects of chemical control in agriculture. PMID:26857741

  11. Metal-organic coordination architectures of azole heterocycle ligands bearing acetic acid groups: Synthesis, structure and magnetic properties

    SciTech Connect

    Hu Bowen; Zhao Jiongpeng; Yang Qian; Hu Tongliang; Du Wenping; Bu Xianhe

    2009-10-15

    Four new coordination complexes with azole heterocycle ligands bearing acetic acid groups, [Co(L{sup 1}){sub 2}]{sub n} (1), [CuL{sup 1}N{sub 3}]{sub n} (2), [Cu(L{sup 2}){sub 2}.0.5C{sub 2}H{sub 5}OH.H{sub 2}O]{sub n} (3) and [Co(L{sup 2}){sub 2}]{sub n} (4) (here, HL{sup 1}=1H-imidazole-1-yl-acetic acid, HL{sup 2}=1H-benzimidazole-1-yl-acetic acid) have been synthesized and structurally characterized. Single-crystal structure analysis shows that 3 and 4 are 2D complexes with 4{sup 4}-sql topologies, while another 2D complex 1 has a (4{sup 3}){sub 2}(4{sup 6})-kgd topology. And 2 is a 3D complex composed dinuclear mu{sub 1,1}-bridging azido Cu{sup II} entities with distorted rutile topology. The magnetic properties of 1 and 2 have been studied. - Graphical Abstract: The synthesis, crystal structure, and magnetic properties of the new coordination complexes with azole heterocycle ligands bearing acetic acid groups are reported.

  12. Application of molecular methods for analysing the distribution and diversity of acetic acid bacteria in Chilean vineyards.

    PubMed

    Prieto, Carmen; Jara, Carla; Mas, Albert; Romero, Jaime

    2007-04-20

    The presence of acetic acid bacteria populations on grape surfaces from several Chilean valleys is reported. The bacteria were analysed at both the species and the strain level by molecular methods such as RFLP-PCR 16S rRNA gene, RFLP-PCR ITS 16S-23S rRNA gene regions and Arbitrary Primed (AP) PCR. Our results show that there are limited numbers of species of acetic acid bacteria in the grapes and that there is a need for an enrichment medium before plating to recover the individual colonies. In the Northernmost region analysed, the major species recovered was a non-acetic acid bacteria, Stenotrophomonas maltophila. Following the North-South axis of Chilean valleys, the observed distribution of acetic acid bacteria was zonified: Acetobacter cerevisiae was only present in the North and Gluconobacter oxydans in the South. Both species were recovered together in only one location. The influence of the grape cultivar was negligible. Variability in strains was found to be high (more than 40%) for both Acetobacteraceae species. PMID:17289199

  13. Identification and characterization of thermotolerant acetic acid bacteria strains isolated from coconut water vinegar in Sri Lanka.

    PubMed

    Perumpuli, P A B N; Watanabe, Taisuke; Toyama, Hirohide

    2014-01-01

    From the pellicle formed on top of brewing coconut water vinegar in Sri Lanka, three Acetobacter strains (SL13E-2, SL13E-3, and SL13E-4) that grow at 42 °C and four Gluconobacter strains (SL13-5, SL13-6, SL13-7, and SL13-8) grow at 37 °C were identified as Acetobacter pasteurianus and Gluconobacter frateurii, respectively. Acetic acid production by the isolated Acetobacter strains was examined. All three strains gave 4% acetic acid from 6% initial ethanol at 37 °C, and 2.5% acetic acid from 4% initial ethanol at 40 °C. Compared with the two other strains, SL13E-4 showed both slower growth and slower acetic acid production. As well as the thermotolerant SKU1108 strain, the activities of the alcohol dehydrogenase and the aldehyde dehydrogenase of SL13E-2 and SL13E-4 were more stable than those of the mesophilic strain. The isolated strains were used to produce coconut water vinegar at higher temperatures than typically used for vinegar production. PMID:25036846

  14. Histologic changes in channel catfish, Ictalurus punctatus Rafinesque, fed diets containing graded levels of gossypol-acetic acid

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A study was performed to evaluate the histologic changes among fingerling channel catfish (Ictalurus punctatus) fed purified diets containing graded levels of gossypol from gossypol–acetic acid. The catfish were maintained on diets with 0, 300, 600, 900, 1200 or 1500 mg gossypol kg-1 diet for 12 we...

  15. Hyaluronic acid embedded cellulose acetate phthlate core/shell nanoparticulate carrier of 5-fluorouracil.

    PubMed

    Garg, Ashish; Rai, Gopal; Lodhi, Santram; Jain, Alok Pal; Yadav, Awesh K

    2016-06-01

    Aim of this research was to prepare hyaluronic acid-modified-cellulose acetate phthalate (HAC) core shell nanoparticles (NPs) of 5-fluorouracil (5-FU). HAC copolymer was synthesized and confirmed by fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopy. HAC NPs with 5-FU were prepared using HAC copolymer and compared with 5-FU loaded cellulose acetate phthalate (CAP) NPs. NPs were characterized by atomic force microscopy (AFM), particle size, zeta potential, polydispersity index, entrapment efficiency, in-vitro release, differential scanning calorimetry (DSC) and X-ray diffraction (XRD). HAC NPs were found slower release (97.30% in 48h) than (99.25% in 8h) CAP NPs. In cytotoxicity studies, showed great cytotoxic potential of 5-FU loaded HAC NPs in A549, MDA-MD-435 and SK-OV-3 cancer cellline. HAC NPs showing least hemolytic than CAP NPs and 5-FU. Area under curve (AUC), maximum plasma concentration (Cmax), mean residence time (MRT) and time to reach maximum plasma concentration Tmax), were observed 4398.1±7.90μgh/mL, 145.45±2.25μg/L, 45.74±0.25h, 72±0.50h, respectively of HAC NPs and 119.92±1.78μgh/mL, 46.38±3.42μg/L, 1.2±0.25h, 0.5±0.02h were observed in plain 5-FU solution. In conclusion, HAC NPs is effective deliver carrier of 5-FU for lung cancer. PMID:26955748

  16. Gas-Phase Thermal Tautomerization of Imidazole-Acetic Acid: Theoretical and Computational Investigations

    PubMed Central

    Aziz, Saadullah G.; Osman, Osman I.; Elroby, Shaaban A.; Hilal, Rifaat H.

    2015-01-01

    The gas-phase thermal tautomerization reaction between imidazole-4-acetic (I) and imidazole-5-acetic (II) acids was monitored using the traditional hybrid functional (B3LYP) and the long-range corrected functionals (CAM-B3LYP and ωB97XD) with 6-311++G** and aug-cc-pvdz basis sets. The roles of the long-range and dispersion corrections on their geometrical parameters, thermodynamic functions, kinetics, dipole moments, Highest Occupied Molecular Orbital–Lowest Unoccupied Molecular Orbital (HOMO–LUMO) energy gaps and total hyperpolarizability were investigated. All tested levels of theory predicted the preference of I over II by 0.750–0.877 kcal/mol. The origin of predilection of I is assigned to the H-bonding interaction (nN8→σ*O14–H15). This interaction stabilized I by 15.07 kcal/mol. The gas-phase interconversion between the two tautomers assumed a 1,2-proton shift mechanism, with two transition states (TS), TS1 and TS2, having energy barriers of 47.67–49.92 and 49.55–52.69 kcal/mol, respectively, and an sp3-type intermediate. A water-assisted 1,3-proton shift route brought the barrier height down to less than 20 kcal/mol in gas-phase and less than 12 kcal/mol in solution. The relatively high values of total hyperpolarizability of I compared to II were interpreted and discussed. PMID:26556336

  17. The effect of lactic acid bacterial starter culture and chemical additives on wilted rice straw silage.

    PubMed

    Wang, Yan-Su; Shi, Wei; Huang, Lin-Ting; Ding, Cheng-Long; Dai, Chuan-Chao

    2016-04-01

    Lactic acid bacteria (LAB) are suitable for rice straw silage fermentation, but have been studied rarely, and rice straw as raw material for ensiling is difficult because of its disadvantages, such as low nutrition for microbial activities and low abundances of natural populations of LAB. So we investigated the effect of application of LAB and chemical additives on the fermentation quality and microbial community of wilted rice straw silage. Treatment with chemical additives increased the concentrations of crude protein (CP), water soluble carbohydrate (WSC), acetic acid and lactic acid, reduced the concentrations of acid detergent fiber (ADF) and neutral detergent fiber (NDF), but did not effectively inhibit the growth of spoilage organisms. Inoculation with LABs did not improve the nutritional value of the silage because of poor growth of LABs in wilted rice straw. Inoculation with LAB and addition of chemical materials improved the quality of silage similar to the effects of addition of chemical materials alone. Growth of aerobic and facultatively anaerobic bacteria was inhibited by this mixed treatment and the LAB gradually dominated the microbial community. In summary, the fermentation quality of wilted rice straw silage had improved by addition of LAB and chemical materials. PMID:26429595

  18. Adamantane dicarboxylic acid esters as possible additives to semisolid lubricants

    SciTech Connect

    Novikova, I.A.; Dolgopolova, T.N.; Apryatkin, A.D.

    1993-12-31

    The high efficiency of adamantane carboxylic acid esters as antiwear additives to lubricating compounds based on polysiloxane liquids has been demonstrated. Dibutyl and dihexyl esters of 5,7-dimethyl-1,3-adainantane dicarboxylic acid, increasing by several factors the efficiency of a semisolid lubricant based on liquid methyldichlorophenylsiloxane, have been synthesized and characterized.

  19. The N-acetylcysteine-insensitive acetic acid-induced yeast programmed cell death occurs without macroautophagy.

    PubMed

    Antonacci, Lucia; Guaragnella, Nicoletta; Ždralevic, Maša; Passarella, Salvatore; Marra, Ersilia; Giannattasio, Sergio

    2012-12-01

    Programmed cell death can occur through two separate pathways caused by treatment of Saccharomyces cerevisiae with acetic acid (AA-PCD), which differ from one another essentially with respect to their sensitivity to N-acetylcysteine (NAC) and to the role played by cytochrome c and metacaspase YCA1. Moreover, yeast can also undergo macroautophagy which occurs in NAC-insensitive manner. In order to gain some insight into the relationship between AA-PCD and macroautophagy use was made of WT and knock-out cells lacking YCA1 and/or cytochrome c. We show that i. macroautophagy is modulated by YCA1 and by cytochrome c in a negative and positive manner, respectively, ii. the NAC-insensitive AA-PCD and macroautophagy differ from one another and iii. NAC-insensitive AA-PCD pathway takes place essentially without macroautophagy, even if the shift of extracellular pH to acidic values required for AA-PCD to occur leads itself to increased or decreased macroautophagy in YCA1 or cytochrome c-lacking cells. PMID:23072389

  20. Immunohistochemical observation of indole-3-acetic acid at the IAA synthetic maize coleoptile tips

    PubMed Central

    Nishimura, Takeshi; Toyooka, Kiminori; Sato, Mayuko; Matsumoto, Sachiko; Lucas, M. Mercedes; Strnad, Miroslav; Baluška, František; Koshiba, Tomokazu

    2011-01-01

    To investigate the distribution of IAA (indole-3-acetic acid) and the IAA synthetic cells in maize coleoptiles, we established immunohistochemistry of IAA using an anti-IAA-C-monoclonal antibody. We first confirmed the specificity of the antibody by comparing the amounts of endogenous free and conjugated IAA to the IAA signal obtained from the IAA antibody. Depletion of endogenous IAA showed a corresponding decrease in immuno-signal intensity and negligible cross-reactivity against IAA-related compounds, including tryptophan, indole-3-acetamide, and conjugated-IAA was observed. Immunolocalization showed that the IAA signal was intense in the approximately 1 mm region and the outer epidermis at the approximately 0.5 mm region from the top of coleoptiles treated with 1-N-naphthylphthalamic acid. By contrast, the IAA immuno-signal in the outer epidermis almost disappeared after 5-methyl-tryptophan treatment. Immunogold labeling of IAA with an anti-IAA-N-polyclonal antibody in the outer-epidermal cells showed cytoplasmic localization of free-IAA, but none in cell walls or vacuoles. These findings indicated that IAA is synthesized in the 0–2.0 mm region of maize coleoptile tips from Trp, in which the outer-epidermal cells of the 0.5 mm tip are the most active IAA synthetic cells. PMID:22112455

  1. Effects of Indole-3-Acetic Acid on the Transcriptional Activities and Stress Tolerance of Bradyrhizobium japonicum

    PubMed Central

    Donati, Andrew J.; Lee, Hae-In; Leveau, Johan H. J.; Chang, Woo-Suk

    2013-01-01

    A genome-wide transcriptional profile of Bradyrhizobium japonicum, the nitrogen-fixing endosymbiont of the soybean plant, revealed differential expression of approximately 15% of the genome after a 1 mM treatment with the phytohormone indole-3-acetic acid (IAA). A total of 1,323 genes were differentially expressed (619 up-regulated and 704 down-regulated) at a two-fold cut off with q value ≤ 0.05. General stress response genes were induced, such as those involved in response to heat, cold, oxidative, osmotic, and desiccation stresses and in exopolysaccharide (EPS) biosynthesis. This suggests that IAA is effective in activating a generalized stress response in B. japonicum. The transcriptional data were corroborated by the finding that stress tolerance of B. japonicum in cell viability assays was enhanced when pre-treated with 1 mM IAA compared to controls. The IAA treatment also stimulated biofilm formation and EPS production by B. japonicum, especially acidic sugar components in the total EPS. The IAA pre-treatment did not influence the nodulation ability of B. japonicum. The data provide a comprehensive overview of the potential transcriptional responses of the symbiotic bacterium when exposed to the ubiquitous hormone of its plant host. PMID:24098533

  2. Indole-3-acetic acid in Fusarium graminearum: Identification of biosynthetic pathways and characterization of physiological effects.

    PubMed

    Luo, Kun; Rocheleau, Hélène; Qi, Peng-Fei; Zheng, You-Liang; Zhao, Hui-Yan; Ouellet, Thérèse

    2016-09-01

    Fusarium graminearum is a devastating pathogenic fungus causing fusarium head blight (FHB) of wheat. This fungus can produce indole-3-acetic acid (IAA) and a very large amount of IAA accumulates in wheat head tissues during the first few days of infection by F. graminearum. Using liquid culture conditions, we have determined that F. graminearum can use tryptamine (TAM) and indole-3-acetonitrile (IAN) as biosynthetic intermediates to produce IAA. It is the first time that F. graminearum is shown to use the l-tryptophan-dependent TAM and IAN pathways rather than the indole-3-acetamide or indole-3-pyruvic acid pathways to produce IAA. Our experiments also showed that exogenous IAA was metabolized by F. graminearum. Exogenous IAA, TAM, and IAN inhibited mycelial growth; IAA and IAN also affected the hyphae branching pattern and delayed macroconidium germination. IAA and TAM had a small positive effect on the production of the mycotoxin 15-ADON while IAN inhibited its production. Our results showed that IAA and biosynthetic intermediates had a significant effect on F. graminearum physiology and suggested a new area of exploration for fungicidal compounds. PMID:27567719

  3. Acetobacter fabarum sp. nov., an acetic acid bacterium from a Ghanaian cocoa bean heap fermentation.

    PubMed

    Cleenwerck, Ilse; Gonzalez, Angel; Camu, Nicholas; Engelbeen, Katrien; De Vos, Paul; De Vuyst, Luc

    2008-09-01

    Six acetic acid bacterial isolates, obtained during a study of the microbial diversity of spontaneous fermentations of Ghanaian cocoa beans, were subjected to a polyphasic taxonomic study. (GTG)(5)-PCR fingerprinting grouped the isolates together, but they could not be identified using this method. Phylogenetic analysis based on 16S rRNA gene sequences allocated the isolates to the genus Acetobacter and revealed Acetobacter lovaniensis, Acetobacter ghanensis and Acetobacter syzygii to be nearest neighbours. DNA-DNA hybridizations demonstrated that the isolates belonged to a single novel genospecies that could be differentiated from its phylogenetically nearest neighbours by the following phenotypic characteristics: no production of 2-keto-D-gluconic acid from D-glucose; growth on methanol and D-xylose, but not on maltose, as sole carbon sources; no growth on yeast extract with 30% D-glucose; and weak growth at 37 degrees C. The DNA G+C contents of four selected strains were 56.8-58.0 mol%. The results obtained prove that the isolates should be classified as representatives of a novel Acetobacter species, for which the name Acetobacter fabarum sp. nov. is proposed. The type strain is strain 985(T) (=R-36330(T) =LMG 24244(T) =DSM 19596(T)). PMID:18768626

  4. Non-growing Rhodopseudomonas palustris Increases the Hydrogen Gas Yield from Acetate by Shifting from the Glyoxylate Shunt to the Tricarboxylic Acid Cycle*

    PubMed Central

    McKinlay, James B.; Oda, Yasuhiro; Rühl, Martin; Posto, Amanda L.; Sauer, Uwe; Harwood, Caroline S.

    2014-01-01

    When starved for nitrogen, non-growing cells of the photosynthetic bacterium Rhodopseudomonas palustris continue to metabolize acetate and produce H2, an important industrial chemical and potential biofuel. The enzyme nitrogenase catalyzes H2 formation. The highest H2 yields are obtained when cells are deprived of N2 and thus use available electrons to synthesize H2 as the exclusive product of nitrogenase. To understand how R. palustris responds metabolically to increase H2 yields when it is starved for N2, and thus not growing, we tracked changes in biomass composition and global transcript levels. In addition to a 3.5-fold higher H2 yield by non-growing cells we also observed an accumulation of polyhydroxybutyrate to over 30% of the dry cell weight. The transcriptome of R. palustris showed down-regulation of biosynthetic processes and up-regulation of nitrogen scavenging mechanisms in response to N2 starvation but gene expression changes did not point to metabolic activities that could generate the reductant necessary to explain the high H2 yield. We therefore tracked 13C-labeled acetate through central metabolic pathways. We found that non-growing cells shifted their metabolism to use the tricarboxylic acid cycle to metabolize acetate in contrast to growing cells, which used the glyoxylate cycle exclusively. This shift enabled cells to more fully oxidize acetate, providing the necessary reducing power to explain the high H2 yield. PMID:24302724

  5. A General Access to Propargylic Ethers through Brønsted Acid Catalyzed Alkynylation of Acetals and Ketals with Trifluoroborates .

    PubMed

    Baxter, Matthew; Bolshan, Yuri

    2015-09-21

    A general Brønsted acid catalyzed methodology for the alkynylation of acetals and ketals with alkynyltrifluoroborate salts has been developed. The reaction proceeds rapidly to afford valuable synthetic building block propargylic ethers in good to excellent yields. Unlike Lewis acid catalyzed transformations of trifluoroborates, this approach does not proceed via unstable organodifluoroborane intermediate. As a result, the developed methodology features excellent functional group tolerance and good atom economy. PMID:26248543

  6. Protective Effect of the Methanolic Extract of Malva parviflora L. leaves on Acetic Acid-induced Ulcerative Colitis in Rats

    PubMed Central

    Dugani, Aisha; Dakhil, Bushra; Treesh, Soad

    2016-01-01

    Background/Aims: Inflammatory bowel disease (IBD) is a general term describing chronic, idiopathic relapsing, inflammatory conditions of the gastrointestinal tract of unknown etiology. Previous studies have indicated that Malva parviflora leaf extract possesses anti-inflammatory, antioxidant, and antiulcerogenic activity. activity. This work aimed to investigatee the anti-inflammatory effect of the methanolic (MEMP) and aqueous (AEMP) extracts of M. parviflora leaves on acetic acid-induced colitis in rats. Materials and Methods: 42 male Wistar albino rats were divided into seven groups (n = 6). Group I: Normal saline control group with no colitis; Group II: Acetic acid colitis group; Group III: 100 mg/kg/5 d MEMP; Group IV: 200 mg/kg/5 d.MEMP; Group V: 100 mg/kg/5 d AEMP; Group VI: 200 mg/kg/5 d AEMP; Group VII: Prednisolone group (2 mg/kg/5 d). Treatments were followed by induction of colitis using intrarectal instillation of 2 mL of 4% acetic acid. Colon damage was evaluated macroscopically (spleen weight/body weight, colon weight/length ratio) and the histological changes were also recorded. Results: The results of this study showed that acetic acid caused severe inflammation of the colon and a significant increase in spleen weight/body weight, and an increase in colon weight/length ratio compared with normal control group. Pretreatment with MEMP and AEMP for 5 days followed by induction of colitis resulted in a significant attenuation of spleen weight and colon weight/length ratio compared with acetic acid control group. Methanolic extract provided better anticolitic effect than aqueous extract; the effect was prominent at the dose of 200 mg/kg. Histopathological findings confirmed the protective effect of the MEMP. Conclusion: In conclusion, MEMP could ameliorate mucosal damage in experimentally induced colitis when given orally. PMID:27184642

  7. Cartilage and bone malformations in the head of zebrafish (Danio rerio) embryos following exposure to disulfiram and acetic acid hydrazide

    SciTech Connect

    Strecker, Ruben; Weigt, Stefan; Braunbeck, Thomas

    2013-04-15

    In order to investigate teratogenic effects, especially on cartilage and bone formation, zebrafish embryos were exposed for 144 h to the dithiocarbamate pesticide disulfiram (20–320 μg/L) and acetic acid hydrazide (0.375–12 g/L), a degradation product of isoniazid. After fixation and full-mount staining, disulfiram could be shown to induce strong cartilage malformations after exposure to ≥ 80 μg/L, whereas acetic acid hydrazide caused cartilage alterations only from 1.5 g/L. Undulating notochords occurred after exposure to disulfiram even at the lowest test concentration of 20 μg/L, whereas at the two lowest concentrations of acetic acid hydrazide (0.375 and 0.75 g/L) mainly fractures of the notochord were observed. Concentrations of acetic acid hydrazide ≥ 1.5 g/L resulted in undulated notochords similar to disulfiram. Cartilages and ossifications of the cranium, including the cleithrum, were individually analyzed assessing the severity of malformation and the degree of ossification in a semi-quantitative approach. Cartilages of the neurocranium such as the ethmoid plate proved to be more stable than cartilages of the pharyngeal skeleton such as Meckel's cartilage. Hence, ossification proved significantly more susceptible than cartilage. The alterations induced in the notochord as well as in the cranium might well be of ecological relevance, since notochord malformation is likely to result in impaired swimming and cranial malformation might compromise regular food uptake. - Highlights: ► Disulfiram and acetic acid hydrazide as notochord, cartilage and bone teratogens ► Zebrafish embryos to model effects on single cartilages and bones in the head ► LC50 calculation and head length measurements after six days post-fertilization ► Lethality, head length and teratogenic effects are dose-dependent. ► Cartilages of the neurocranium are the most stable elements in the head.

  8. Strategies for enhancing the production of penicillin G acylase from Bacillus badius: influence of phenyl acetic acid dosage.

    PubMed

    Rajendran, Karthikeyan; Mahadevan, Surianarayanan; Jeyaprakash, Rajendhran; Paramasamy, Gunasekaran; Mandal, Asit Baran

    2013-11-01

    Bacillus badius isolated from soil has been identified as potential producer of penicillin G acylase (PGA). In the present study, batch experiments performed at optimized inoculum size, temperature, pH, and agitation yielded a maximum PGA of 9.5 U/ml in shake flask. The experiments conducted in bioreactor with different oxygen flow rates revealed that 0.66 vvm oxygen flow rate could be sufficient for the maximum PGA activity of 12.7 U/ml. From a detailed investigation on the strategies of the addition of phenyl acetic acid (PAA) for increasing the production of PGA, it was found that the controlled addition of 10 ml of 0.1 % (w/v) PAA once in every 2 h from 6th hour of growth showed the maximum PGA activity of 32 U/ml. Thus, our studies for the first time showed that at concentration above 0.1 % (w/v) PAA, the PGA production decreased. This selective condition paves the way for less costly bioprocess for the production of PGA. PMID:23949729

  9. Distinct Characteristics of Indole-3-Acetic Acid and Phenylacetic Acid, Two Common Auxins in Plants.

    PubMed

    Sugawara, Satoko; Mashiguchi, Kiyoshi; Tanaka, Keita; Hishiyama, Shojiro; Sakai, Tatsuya; Hanada, Kousuke; Kinoshita-Tsujimura, Kaori; Yu, Hong; Dai, Xinhua; Takebayashi, Yumiko; Takeda-Kamiya, Noriko; Kakimoto, Tatsuo; Kawaide, Hiroshi; Natsume, Masahiro; Estelle, Mark; Zhao, Yunde; Hayashi, Ken-Ichiro; Kamiya, Yuji; Kasahara, Hiroyuki

    2015-08-01

    The phytohormone auxin plays a central role in many aspects of plant growth and development. IAA is the most studied natural auxin that possesses the property of polar transport in plants. Phenylacetic acid (PAA) has also been recognized as a natural auxin for >40 years, but its role in plant growth and development remains unclear. In this study, we show that IAA and PAA have overlapping regulatory roles but distinct transport characteristics as auxins in plants. PAA is widely distributed in vascular and non-vascular plants. Although the biological activities of PAA are lower than those of IAA, the endogenous levels of PAA are much higher than those of IAA in various plant tissues in Arabidopsis. PAA and IAA can regulate the same set of auxin-responsive genes through the TIR1/AFB pathway in Arabidopsis. IAA actively forms concentration gradients in maize coleoptiles in response to gravitropic stimulation, whereas PAA does not, indicating that PAA is not actively transported in a polar manner. The induction of the YUCCA (YUC) genes increases PAA metabolite levels in Arabidopsis, indicating that YUC flavin-containing monooxygenases may play a role in PAA biosynthesis. Our results provide new insights into the regulation of plant growth and development by different types of auxins. PMID:26076971

  10. Distinct Characteristics of Indole-3-Acetic Acid and Phenylacetic Acid, Two Common Auxins in Plants

    PubMed Central

    Sugawara, Satoko; Mashiguchi, Kiyoshi; Tanaka, Keita; Hishiyama, Shojiro; Sakai, Tatsuya; Hanada, Kousuke; Kinoshita-Tsujimura, Kaori; Yu, Hong; Dai, Xinhua; Takebayashi, Yumiko; Takeda-Kamiya, Noriko; Kakimoto, Tatsuo; Kawaide, Hiroshi; Natsume, Masahiro; Estelle, Mark; Zhao, Yunde; Hayashi, Ken-ichiro; Kamiya, Yuji; Kasahara, Hiroyuki

    2015-01-01

    The phytohormone auxin plays a central role in many aspects of plant growth and development. IAA is the most studied natural auxin that possesses the property of polar transport in plants. Phenylacetic acid (PAA) has also been recognized as a natural auxin for >40 years, but its role in plant growth and development remains unclear. In this study, we show that IAA and PAA have overlapping regulatory roles but distinct transport characteristics as auxins in plants. PAA is widely distributed in vascular and non-vascular plants. Although the biological activities of PAA are lower than those of IAA, the endogenous levels of PAA are much higher than those of IAA in various plant tissues in Arabidopsis. PAA and IAA can regulate the same set of auxin-responsive genes through the TIR1/AFB pathway in Arabidopsis. IAA actively forms concentration gradients in maize coleoptiles in response to gravitropic stimulation, whereas PAA does not, indicating that PAA is not actively transported in a polar manner. The induction of the YUCCA (YUC) genes increases PAA metabolite levels in Arabidopsis, indicating that YUC flavin-containing monooxygenases may play a role in PAA biosynthesis. Our results provide new insights into the regulation of plant growth and development by different types of auxins. PMID:26076971

  11. Updates on quick identification of acetic acid bacteria with a focus on the 16S-23S rRNA gene internal transcribed spacer and the analysis of cell proteins by MALDI-TOF mass spectrometry.

    PubMed

    Trček, Janja; Barja, François

    2015-03-01

    Acetic acid bacteria have attracted much attention over the past few years, due mainly to their metabolic traits that are of interest to the biotechnology industry. In addition, it turns out that their ecological habitats are almost unlimited since they have been found as symbionts in different insects and also as emerging opportunistic human pathogens. Very surprising is the finding that they colonize niches considered anaerobic, disproving the generalized statement that they are strict aerobes. Since they have taken on different biological roles in our environment, more and more people are charged with the task of identifying them. However, this turns out to be not always easy, especially if we are using phenotypic approaches for identification. A substantial step forward in making the identification of acetic acid bacteria easier was made possible using molecular biological methods, which have been extensively tested since 2000. However, some molecular methods require expensive machines and experienced staff, and moreover the level of their discrimination varies. All these factors must be considered when selecting the most appropriate approach for identifying acetic acid bacteria. With this objective in mind, this review article discusses the benefits and drawbacks of molecular biological methods for identification of acetic acid bacteria, with a focus on the 16S-23S rRNA gene ITS regions and the recently described alternative method for identification of acetic acid bacteria, MALDI-TOF MS. PMID:25589227

  12. Studies on the growth and indole-3-acetic acid and abscisic acid content of Zea mays seedlings grown in microgravity

    NASA Technical Reports Server (NTRS)

    Schulze, A.; Jensen, P. J.; Desrosiers, M.; Buta, J. G.; Bandurski, R. S.

    1992-01-01

    Measurements were made of the fresh weight, dry weight, dry weight-fresh weight ratio, free and conjugated indole-3-acetic acid, and free and conjugated abscisic acid in seedlings of Zea mays grown in darkness in microgravity and on earth. Imbibition of the dry kernels was 17 h prior to launch. Growth was for 5 d at ambient orbiter temperature and at a chronic accelerational force of the order of 3 x 10(-5) times earth gravity. Weights and hormone content of the microgravity seedlings were, with minor exceptions, not statistically different from seedlings grown in normal gravity. The tissues of the shuttle-grown plants appeared normal and the seedlings differed only in the lack of orientation of roots and shoots. These findings, based upon 5 d of growth in microgravity, cannot be extrapolated to growth in microgravity for weeks, months, and years, as might occur on a space station. Nonetheless, it is encouraging, for prospects of bioregeneration of the atmosphere and food production in a space station, that no pronounced differences in the parameters measured were apparent during the 5 d of plant seedling growth in microgravity.

  13. Bi(OTf)3-catalyzed addition of isocyanides to 2H-chromene acetals: an efficient pathway for accessing 2-carboxamide-2H-chromenes.

    PubMed

    Lyu, Longyun; Jin, Ming Yu; He, Qijie; Xie, Han; Bian, Zhaoxiang; Wang, Jun

    2016-09-14

    Bismuth triflate (Bi(OTf)3) is identified as an efficient catalyst for the direct addition of isocyanides to 2H-chromene acetals. The large scope of isocyanides and chromene acetals makes them suitable substrates in this catalytic system. By this synthetic strategy, a polyfunctional molecular scaffold, 2-carboxamide-2H-chromenes could be prepared efficiently in one step up to 95% yield. In addition, this efficient and practical protocol proceeded smoothly in the gram scale even when the catalytic loading was reduced to 2 mol%. PMID:27503764

  14. Role of nitric oxide in the convulsive seizures induced by fluoroquinolones coadministered with 4-biphenyl acetic acid.

    PubMed

    Kohno, K; Niwa, M; Nozaki, M; Uematsu, T; Fujimura, H

    1997-11-01

    1. Contribution of nitric oxide to the convulsive seizures induced by fluoroquinolones (FQs) coadministered with 4-biphenyl acetic acid (BPAA), the active metabolite of fenbufen, was assessed in mice. 2. Enoxacin + 4-biphenyl acetic acid caused clonic seizures in all treated mice, followed by tonic seizures and death. These events were associated with a significant increase in intracerebellar cyclic GMP. 3. Pretreatment with the nitric oxide synthase (NOS) inhibitor, NG-nitro-L-arginine methylester (L-NAME), but not with D-NAME, significantly reduced the incidence of convulsions and lethality, as well as the increase in cyclic GMP. 4. Pretreatment with N-methyl-D-aspartic acid (NMDA)-receptor antagonist, MK-801, inhibited only the transition of clonic seizure to tonic seizure without affecting the incidence of clonic seizure and lethality. 5. These findings suggest that FQs + BPAA exert convulsions by activating NOS partly through the mediation of the NMDA receptor in the brain cells. PMID:9347323

  15. PEP3 overexpression shortens lag phase but does not alter growth rate in Saccharomyces cerevisiae exposed to acetic acid stress.

    PubMed

    Ding, Jun; Holzwarth, Garrett; Bradford, C Samuel; Cooley, Ben; Yoshinaga, Allen S; Patton-Vogt, Jana; Abeliovich, Hagai; Penner, Michael H; Bakalinsky, Alan T

    2015-10-01

    In fungi, two recognized mechanisms contribute to pH homeostasis: the plasma membrane proton-pumping ATPase that exports excess protons and the vacuolar proton-pumping ATPase (V-ATPase) that mediates vacuolar proton uptake. Here, we report that overexpression of PEP3 which encodes a component of the HOPS and CORVET complexes involved in vacuolar biogenesis, shortened lag phase in Saccharomyces cerevisiae exposed to acetic acid stress. By confocal microscopy, PEP3-overexpressing cells stained with the vacuolar membrane-specific dye, FM4-64 had more fragmented vacuoles than the wild-type control. The stained overexpression mutant was also found to exhibit about 3.6-fold more FM4-64 fluorescence than the wild-type control as determined by flow cytometry. While the vacuolar pH of the wild-type strain grown in the presence of 80 mM acetic acid was significantly higher than in the absence of added acid, no significant difference was observed in vacuolar pH of the overexpression strain grown either in the presence or absence of 80 mM acetic acid. Based on an indirect growth assay, the PEP3-overexpression strain exhibited higher V-ATPase activity. We hypothesize that PEP3 overexpression provides protection from acid stress by increasing vacuolar surface area and V-ATPase activity and, hence, proton-sequestering capacity. PMID:26051671

  16. Studies of the chemistry of the [Ru(H{sub 2}O)Cl{sub 5}]{sup 2{minus}} form of ruthenium(III) in acetic acid solutions

    SciTech Connect

    Buslaeva, T.M.; Rudnitskaya, O.V.; Marov, I.N.; Red`kina, S.N.; Belyaeva, V.K.

    1995-03-01

    The behavior of the [Ru(H{sub 2}O)Cl{sub 5}]{sup 2{minus}} form of ruthenium(III) in acetic acid solutions is studied for the first time. It is established that, when the solution of the title complex is allowed to stand in 8.5 M CH{sub 3}COOH at 50{degrees}C, it first hydrates with simultaneous substitution of the acetate ions for the water molecules to form the [Ru(H{sub 2}O)Cl{sub 4}(CH{sub 3}COO)]{sup 2{minus}} and/or [RuCl{sub 4}(CH{sub 3}COO){sub 2}]{sup 3{minus}} complexes in addition to [Ru(H{sub 2}O){sub 2}Cl{sub 4}]{sup {minus}}. The two former complexes yield EPR signals with 2.68 and 2.52 g-factors, respectively. It is noted that EPR spectra with g = 2.31, 2.21, 2.09, and 2.05 can belong both to the mono- and polynuclear ruthenium(III) compounds that are formed in reaction of the parent complex with acetic acid. Experimental evidence favoring both currently suggested concepts is presented.

  17. Kinetics of catalytic hydrogenation of 4-nitroaniline in aqueous solutions of propan-2-ol with acid or base additives

    NASA Astrophysics Data System (ADS)

    Kha, Nguen Tkhi Tkhu; Merkin, A. A.; Komarov, A. A.; Korpatenkov, D. O.; Lefedova, O. V.

    2014-04-01

    The effect of addition of acetic acid and sodium hydroxide to an aqueous azeotropic solution of propan-2-ol on the rate of 4-nitroaniline hydrogenation is studied. The base additive accelerates the apparent rate of nitro group reduction, while the presence of acetic acid slows the reaction rate. It is experimentally established that the rate of nitro group conversion calculated from the amount of reacted 4-nitroaniline exceeds the rate of hydrogen uptake from the gas phase in all of the studied solvents. Hydrogen bound by active sites of the catalyst surface is found to participate notably in the reactions. It is proved both experimentally and theoretically that strongly bound atomic forms of adsorbed hydrogen are most active in the reduction of the nitro group.

  18. Biodiversity of yeasts, lactic acid bacteria and acetic acid bacteria in the fermentation of "Shanxi aged vinegar", a traditional Chinese vinegar.

    PubMed

    Wu, Jia Jia; Ma, Ying Kun; Zhang, Fen Fen; Chen, Fu Sheng

    2012-05-01

    Shanxi aged vinegar is a famous traditional Chinese vinegar made from several kinds of cereal by spontaneous solid-state fermentation techniques. In order to get a comprehensive understanding of culturable microorganism's diversity present in its fermentation, the indigenous microorganisms including 47 yeast isolates, 28 lactic acid bacteria isolates and 58 acetic acid bacteria isolates were recovered in different fermenting time and characterized based on a combination of phenotypic and genotypic approaches including inter-delta/PCR, PCR-RFLP, ERIC/PCR analysis, as well as 16S rRNA and 26S rRNA partial gene sequencing. In the alcoholic fermentation, the dominant yeast species Saccharomyces (S.) cerevisiae (96%) exhibited low phenotypic and genotypic diversity among the isolates, while Lactobacillus (Lb.) fermentum together with Lb. plantarum, Lb. buchneri, Lb. casei, Pediococcus (P.) acidilactici, P. pentosaceus and Weissella confusa were predominated in the bacterial population at the same stage. Acetobacter (A.) pasteurianus showing great variety both in genotypic and phenotypic tests was the dominant species (76%) in the acetic acid fermentation stage, while the other acetic acid bacteria species including A. senegalensis, A. indonesiensis, A. malorum and A. orientalis, as well as Gluconobacter (G.) oxydans were detected at initial point of alcoholic and acetic acid fermentation stage respectively. PMID:22265314

  19. Standardization of DNA extraction from methanol acetic acid fixed cytogenetic cells of cattle and buffalo.

    PubMed

    Kotikalapudi, Rosaiah; Patel, Rajesh K; Katragadda, Sanghamitra

    2013-12-01

    The aim of the study is to standardize the simple method for extracting DNA from cells fixed in fixative (3:1 ratio of methanol and acetic acid glacial) mostly used for chromosomal studies in cattle and buffaloes. These fixed cells were stored for more than 6 months at refrigerated temperature. The fixed cells were washed 2-3 times by the ice cold 1x Phosphate Buffer Saline (PBS) with pH 7.4, so that effect of fixative may be eliminated. The genomic DNA was extracted by adding cell lysis and nucleus lysis buffers. The quality and quantity of DNA were estimated. The readings of nano drop and agarose gel electrophoresis indicate good quality DNA isolated with a rapid and simple protocol routinely using in our laboratory. The method enables us to study the DNA of a cattle and buffaloes after completing cytogenetic investigation or in cases where DNA samples are otherwise not available. This protocol may be useful for molecular analysis of DNA from fixed cells palettes. PMID:24506057

  20. Process control, energy recovery and cost savings in acetic acid wastewater treatment.

    PubMed

    Vaiopoulou, E; Melidis, P; Aivasidis, A

    2011-02-28

    An anaerobic fixed bed loop (AFBL) reactor was applied for treatment of acetic acid (HAc) wastewater. Two pH process control concepts were investigated; auxostatic and chemostatic control. In the auxostatic pH control, feed pump is interrupted when pH falls below a certain pH value in the bioreactor, which results in reactor operation at maximum load. Chemostatic control assures alkaline conditions by setting a certain pH value in the influent, preventing initial reactor acidification. The AFBL reactor treated HAc wastewater at low hydraulic residence time (HRT) (10-12 h), performed at high space time loads (40-45 kg COD/m(3) d) and high space time yield (30-35 kg COD/m(3) d) to achieve high COD (Chemical Oxygen Demand) removal (80%). Material and cost savings were accomplished by utilizing the microbial potential for wastewater neutralization during anaerobic treatment along with application of favourable pH-auxostatic control. NaOH requirement for neutralization was reduced by 75% and HRT was increased up to 20 h. Energy was recovered by applying costless CO(2) contained in the biogas for neutralization of alkaline wastewater. Biogas was enriched in methane by 4 times. This actually brings in more energy profits, since biogas extra heating for CO(2) content during biogas combustion is minimized and usage of other acidifying agents is omitted. PMID:21168957

  1. Achievements and perspectives in yeast acetic acid-induced programmed cell death pathways.

    PubMed

    Guaragnella, Nicoletta; Antonacci, Lucia; Passarella, Salvatore; Marra, Ersilia; Giannattasio, Sergio

    2011-10-01

    The use of non-mammalian model organisms, including yeast Saccharomyces cerevisiae, can provide new insights into eukaryotic PCD (programmed cell death) pathways. In the present paper, we report recent achievements in the elucidation of the events leading to PCD that occur as a response to yeast treatment with AA (acetic acid). In particular, ROS (reactive oxygen species) generation, cyt c (cytochrome c) release and mitochondrial function and proteolytic activity will be dealt with as they vary along the AA-PCD time course by using both wild-type and mutant yeast cells. Two AA-PCD pathways are described sharing common features, but distinct from one another with respect to the role of ROS and mitochondria, the former in which YCA1 acts upstream of cyt c release and caspase-like activation in a ROS-dependent manner and the latter in which cyt c release does not occur, but caspase-like activity increases, in a ROS-independent manner. PMID:21936848

  2. Intraperitoneal administration of butyrate prevents the severity of acetic acid colitis in rats

    PubMed Central

    Malago, Joshua J.; Sangu, Catherine L.

    2015-01-01

    Intrarectal infusion of butyrate improves colorectal disorders including ulcerative colitis (UC). However, it is not established whether systemically administered butyrate benefits such patients. The current study aimed at exploring and comparing the potential of intraperitoneally, intrarectally, and orally administered butyrate against acetic acid (AA)-induced UC in rats. Intrarectal administration of 2 ml of 50% AA was done after or without prior treatment of rats for 7 consecutive days with 100 mg/kg sodium butyrate (SB) intraperitoneally, intrarectally, or orally. Rats were sacrificed after 48 h of AA-treatment. Subsequently, colon sections were processed routinely for histopathological examination. We clinically observed diarrhea, loose stools, and hemoccult-positive stools, and histologically, epithelial loss and ulceration, crypt damage, goblet cell depletion, hemorrhage, and mucosal infiltration of inflammatory cells. The changes were significantly reduced by intraperitoneal, intrarectal, or oral butyrate, with intraperitoneal butyrate exhibiting the highest potency. It is concluded that intraperitoneal administration of butyrate abrogates the lesions of AA-induced UC and its potency surpasses that of intrarectal or oral butyrate. PMID:25743124

  3. Endohyphal Bacterium Enhances Production of Indole-3-Acetic Acid by a Foliar Fungal Endophyte

    PubMed Central

    Hoffman, Michele T.; Gunatilaka, Malkanthi K.; Wijeratne, Kithsiri; Gunatilaka, Leslie; Arnold, A. Elizabeth

    2013-01-01

    Numerous plant pathogens, rhizosphere symbionts, and endophytic bacteria and yeasts produce the important phytohormone indole-3-acetic acid (IAA), often with profound effects on host plants. However, to date IAA production has not been documented among foliar endophytes -- the diverse guild of primarily filamentous Ascomycota that live within healthy, above-ground tissues of all plant species studied thus far. Recently bacteria that live within hyphae of endophytes (endohyphal bacteria) have been detected, but their effects have not been studied previously. Here we show not only that IAA is produced in vitro by a foliar endophyte (here identified as Pestalotiopsis aff. neglecta, Xylariales), but that IAA production is enhanced significantly when the endophyte hosts an endohyphal bacterium (here identified as Luteibacter sp., Xanthomonadales). Both the endophyte and the endophyte/bacterium complex appear to rely on an L-tryptophan dependent pathway for IAA synthesis. The bacterium can be isolated from the fungus when the symbiotic complex is cultivated at 36°C. In pure culture the bacterium does not produce IAA. Culture filtrate from the endophyte-bacterium complex significantly enhances growth of tomato in vitro relative to controls and to filtrate from the endophyte alone. Together these results speak to a facultative symbiosis between an endophyte and endohyphal bacterium that strongly influences IAA production, providing a new framework in which to explore endophyte-plant interactions. PMID:24086270

  4. Nitric oxide metabolism and indole acetic acid biosynthesis cross-talk in Azospirillum brasilense SM.

    PubMed

    Koul, Vatsala; Tripathi, Chandrakant; Adholeya, Alok; Kochar, Mandira

    2015-04-01

    Production of nitric oxide (NO) and the presence of NO metabolism genes, nitrous oxide reductase (nosZ), nitrous oxide reductase regulator (nosR) and nitric oxide reductase (norB) were identified in the plant-associated bacterium (PAB) Azospirillum brasilense SM. NO presence was confirmed in all overexpressing strains, while improvement in the plant growth response of these strains was mediated by increased NO and indole-3-acetic acid (IAA) levels in the strains. Electron microscopy showed random distribution to biofilm, with surface colonization of pleiomorphic Azospirilla. Quantitative IAA estimation highlighted a crucial role of nosR and norBC in regulating IAA biosynthesis. The NO quencher and donor reduced/blocked IAA biosynthesis by all strains, indicating their common regulatory role in IAA biosynthesis. Tryptophan (Trp) and l-Arginine (Arg) showed higher expression of NO genes tested, while in the case of ipdC, only Trp and IAA increased expression, while Arg had no significant effect. The highest nosR expression in SMnosR in the presence of IAA and Trp, along with its 2-fold IAA level, confirmed the relationship of nosR overexpression with Trp in increasing IAA. These results indicate a strong correlation between IAA and NO in A. brasilense SM and suggest the existence of cross-talk or shared signaling mechanisms in these two growth regulators. PMID:25700632

  5. Acetic acid effects on methanogens in the second stage of a two-stage anaerobic system.

    PubMed

    Xiao, Keke; Guo, Chenghong; Zhou, Yan; Maspolim, Yogananda; Ng, Wun-Jern

    2016-02-01

    This study reports on biomass tolerance towards high concentrations of acetic acid (HAc) within the system. Biomass from the second stage of a two-stage anaerobic sludge digestion system was used for this study. Microbial community analysis by 454 pyrosequencing highlighted hydrogenotrophic Methanomicrobiales was the predominant archaeal population in the second stage (>99% of the total archaeal community). Second stage biomass degraded HAc up to 4200 mg HAc L(-1) without observable lag phase. However, at HAc-shock loading of 7400 mg HAc L(-1), it showed a one day lag phase associated with decreased biomass activity. After stepwise HAc-acclimation over 27 d, the biomass degraded HAc of up to 8200 mg HAc L(-1) without observable lag phase. The dominance of Methanomicrobiales had remained unchanged in proportion - while the total archaeal population increased during acclimation. This study showed stepwise acclimation could be an approach to accommodate HAc accumulation and hence higher concentrations resulting from an enhanced first stage. PMID:26498097

  6. Cellulose production and cellulose synthase gene detection in acetic acid bacteria.

    PubMed

    Valera, Maria José; Torija, Maria Jesús; Mas, Albert; Mateo, Estibaliz

    2015-02-01

    The ability of acetic acid bacteria (AAB) to produce cellulose has gained much industrial interest due to the physical and chemical characteristics of bacterial cellulose. The production of cellulose occurs in the presence of oxygen and in a glucose-containing medium, but it can also occur during vinegar elaboration by the traditional method. The vinegar biofilm produced by AAB on the air-liquid interface is primarily composed of cellulose and maintains the cells in close contact with oxygen. In this study, we screened for the ability of AAB to produce cellulose using different carbon sources in the presence or absence of ethanol. The presence of cellulose in biofilms was confirmed using the fluorochrome Calcofluor by microscopy. Moreover, the process of biofilm formation was monitored under epifluorescence microscopy using the Live/Dead BacLight Kit. A total of 77 AAB strains belonging to 35 species of Acetobacter, Komagataeibacter, Gluconacetobacter, and Gluconobacter were analysed, and 30 strains were able to produce a cellulose biofilm in at least one condition. This cellulose production was correlated with the PCR amplification of the bcsA gene that encodes cellulose synthase. A total of eight degenerated primers were designed, resulting in one primer pair that was able to detect the presence of this gene in 27 AAB strains, 26 of which formed cellulose. PMID:25381910

  7. Modulation of endogenous indole-3-acetic acid biosynthesis in bacteroids within Medicago sativa nodules.

    PubMed

    Bianco, C; Senatore, B; Arbucci, S; Pieraccini, G; Defez, R

    2014-07-01

    To evaluate the dose-response effects of endogenous indole-3-acetic acid (IAA) on Medicago plant growth and dry weight production, we increased the synthesis of IAA in both free-living and symbiosis-stage rhizobial bacteroids during Rhizobium-legume symbiosis. For this purpose, site-directed mutagenesis was applied to modify an 85-bp promoter sequence, driving the expression of iaaM and tms2 genes for IAA biosynthesis. A positive correlation was found between the higher expression of IAA biosynthetic genes in free-living bacteria and the increased production of IAA under both free-living and symbiotic conditions. Plants nodulated by RD65 and RD66 strains, synthetizing the highest IAA concentration, showed a significant (up to 73%) increase in the shoot fresh weight and upregulation of nitrogenase gene, nifH, compared to plants nodulated by the wild-type strain. When these plants were analyzed by confocal microscopy, using an anti-IAA antibody, the strongest signal was observed in bacteroids of Medicago sativa RD66 (Ms-RD66) plants, even when they were located in the senescent nodule zone. We show here a simple system to modulate endogenous IAA biosynthesis in bacteria nodulating legumes suitable to investigate which is the maximum level of IAA biosynthesis, resulting in the maximal increase of plant growth. PMID:24814784

  8. Sphere of influence of indole acetic acid and nitric oxide in bacteria.

    PubMed

    Koul, Vatsala; Adholeya, Alok; Kochar, Mandira

    2015-05-01

    Bacterial biosynthesis of the phytohormone, indole-3-acetic acid (IAA) is well established and along with the diffusible gaseous molecule, nitric oxide (NO) is known to positively regulate the developmental processes of plant roots. IAA and NO act as signaling molecules in plant-microbe interactions as they modulate the gene expression in both, plants and microorganisms. Although IAA and NO may not be required for essential bacterial physiological processes, numerous studies point towards a crosstalk between IAA and NO in the rhizosphere. In this review, we describe various IAA and NO-responsive or sensing genes/proteins/regulators. There is also growing evidence for the interaction of IAA and NO with other plant growth regulators and the involvement of NO with the quorum sensing system in biofilm formation and virulence. This interactive network can greatly impact the host plant-microbe interactions in the soil. Coupled with this, the specialized σ(54) -dependent transcription observed in some of the IAA and NO-influenced genes can confer inducibility to these traits in bacteria and may allow the expression of IAA and NO-influenced microbial genes in nutrient limiting or changing environmental conditions for the benefit of plants. PMID:24913042

  9. Systematic profiling of indole-3-acetic acid biosynthesis in bacteria using LC-MS/MS.

    PubMed

    Lin, Guang-Huey; Chang, Chung-Yu; Lin, Huei-Ru

    2015-04-15

    Indole-3-acetic acid (IAA) is produced from tryptophan through five synthesis pathways. A comprehensive method for the quantification of IAA and biosynthesis-related intermediates in a culture medium was developed. Sample preparation was simple with protein precipitation. The analytes were separated on a superficially porous C18 silica column and detected by electrospray ionization-tandem mass spectrometry in the positive ion multiple reaction monitoring mode. The limit of detection was 0.05 μM, and the lower limits of quantification ranged from 0.05 to 2 μM. The intra-day and inter-day precision and accuracy were less than 13.96%. Ion suppression was observed, and the deuterated internal standards were used to compensate for the matrix effect. The method was applied to analyze changes in tryptophan catabolism in a culture medium of Pseudomonas putida. The proposed method is robust and suitable for the systematic profiling of IAA biosynthesis in culture supernatant. PMID:25746752

  10. Production of indole-3-acetic acid by the cyanobacterium Arthrospira platensis strain MMG-9.

    PubMed

    Ahmed, Mehboob; Stal, Lucas; Hasnain, Shahida

    2010-09-01

    The filamentous cyanobacterium Arthrospira platensis strain MMG-9 was isolated from a rice field. The ability of this strain to synthesize the bioactive compound indole-3-acetic acid (IAA) was demonstrated. IAA was extracted from the culture A. platensis strain MMG-9 and its identity was confirmed by thin layer chromatography (TLC) as well as by high performance liquid chromatography (HPLC). The IAA precursor L-tryptophan was required for IAA biosynthesis. Released IAA increased with the increase of the initial concentration of L-tryptophan in the medium and with the incubation time. A. platensis strain MMG-9 accumulates more IAA than it released it into the medium. The bioactivity of the secreted IAA was shown by its effect on the formation of roots by Pisum sativum. There was a significant positive effect of the supernatant of cultures of A. platensis strain MMG-9 on the number of lateral roots of P. sativum while a negative effect on root length was observed. PMID:20890089

  11. Temperature-Sensitive Plant Cells with Shunted Indole-3-Acetic Acid Conjugation.

    PubMed Central

    Oetiker, J. H.; Aeschbacher, G.

    1997-01-01

    Cells of henbane (Hyoscyamus muticus L.) grow indefinitely in culture without exogenous auxin. Cells of its temperature-sensitive variant XIIB2 grow like the wild type at 26[deg]C but die rapidly at 33[deg]C unless auxin is added to the medium. Despite this temperature-sensitive auxin auxotrophy, XIIB2 produces wild-type amounts of indole-3-acetic acid (IAA). IAA is the predominant auxin and is important for plant growth and development. Since the IAA production of the variant is functional, we investigated whether the synthesis or degradation of IAA metabolites, possibly active auxins themselves, is altered. The IAA metabolites were IAA-aspartate (IAAsp) and IAA-glucose. The wild type converted IAA mainly to IAAsp, whereas the variant produced mainly IAA-glucose. Exogenous auxin corrected the shunted IAA metabolism of the variant. The half-life of labeled IAAsp in the variant was reduced 21-fold, but in the presence of exogenous auxin it was not different from the wild type. The temperature sensitivity of XIIB2 was also corrected by supplying IAAsp. Pulse-chase experiments revealed that henbane rapidly metabolizes IAAsp to compounds not identical to IAA. The data show that the variant XIIB2 is a useful tool to study the function of IAA conjugates to challenge the popular hypothesis that IAA conjugates are merely slow-release storage forms of IAA. PMID:12223777

  12. Asaia krungthepensis sp. nov., an acetic acid bacterium in the alpha-Proteobacteria.

    PubMed

    Yukphan, Pattaraporn; Potacharoen, Wanchern; Tanasupawat, Somboon; Tanticharoen, Morakot; Yamada, Yuzo

    2004-03-01

    Three bacterial strains were isolated from flowers collected in Bangkok, Thailand, by an enrichment-culture approach for acetic acid bacteria. Phylogenetic analysis based on 16S rRNA gene sequences showed that the isolates were located in the lineage of the genus Asaia but constituted a cluster separate from the type strains of Asaia bogorensis and Asaia siamensis. The DNA base composition of the isolates was 60.2-60.5 mol% G+C, with a range of 0.3 mol%. The isolates constituted a taxon separate from Asaia bogorensis and Asaia siamensis on the basis of DNA-DNA relatedness. The isolates had morphological, physiological, biochemical and chemotaxonomic characteristics similar to those of the type strains of Asaia bogorensis and Asaia siamensis, but the isolates grew on maltose. The major ubiquinone was Q(10). On the basis of the results obtained, the name Asaia krungthepensis sp. nov. is proposed for the isolates. The type strain is isolate AA08(T) (=BCC 12978(T)=TISTR 1524(T)=NBRC 100057(T)=NRIC 0535(T)), which had a DNA G+C content of 60.3 mol% and was isolated from a heliconia flower ('paksaasawan' in Thai; Heliconia sp.) collected in Bangkok, Thailand. PMID:15023938

  13. Hydrolysis of Indole-3-Acetic Acid Esters Exposed to Mild Alkaline Conditions 1

    PubMed Central

    Baldi, Bruce G.; Maher, Barbara R.; Cohen, Jerry D.

    1989-01-01

    Ester conjugates of indole-3-acetic acid are hydrolyzed easily in basic solutions; however, quantitative data have not been available on the relationship between pH and rate of hydrolysis of the known ester conjugates. The use of basic conditions during extraction or purification of IAA by several laboratories suggested that a more systematic analysis of this process was needed. In this report we present data indicating: (a) that measurable hydrolysis of IAA-glucose (from standard solutions) and IAA-esters (from maize kernel extracts) occurs with only a few hours of treatment at pH 9 or above; (b) that the lability of some ester conjugates is even greater than that of IAA-glucose; and (c) that ester hydrolysis of standard compounds, IAA-glucose and IAA-p-nitrophenol, occurs in the `three phase extraction system' proposed by Liu and Tillberg ([1983] Physiol Plant 57: 441-447). These data indicate that the potential for problems with inadvertent hydrolysis of ester conjugates of IAA exists even at moderate pH values and in the multiphase system where exposure to basic conditions was thought to be limited. PMID:16667049

  14. Dissociation of water and Acetic acid on PbS from first principles

    NASA Astrophysics Data System (ADS)

    Satta, Alessandra; Ruggerone, Paolo; de Giudici, Giovanni

    2008-03-01

    The adsorption of complex molecules at mineral surfaces are crucial ingredients for understanding the mechanisms that rule the interaction between minerals and the biosphere and for predicting both the stability and the reactivity of minerals. The present work focuses mainly on the early stages of different adsorption reactions occurring at both the cleavage surface and a high-index vicinal surface of galena (PbS). We have studied the dissociation mechanism of water and acetic acid on the galena surfaces by means of ab initio calculations within the framework of the density functional theory in the generalized gradient approximation and of pseudopotential approach. The calculated adsorption energies of the molecules indicate the stepped surface as the most reactive, as expected. The free energy surface during the reaction process has been explored via metadynamics[1]. The optimized configurations of both reactants and products obtained, were then used to accurately calculate the dissociation energy via the Nudge Elastic Band method[2]. [1] A. Laio and M. Parrinello, PNAS 99, 12562 (2002). [2] G. Mills and H. Jonsson, Phys. Rev. Lett. 72, 1124 (1994).

  15. Application of molecular methods for routine identification of acetic acid bacteria.

    PubMed

    González, Angel; Guillamón, José Manuel; Mas, Albert; Poblet, Montse

    2006-04-15

    Recently many new species of Acetic acid Bacteria have been described. The description and identification as new species was based on molecular techniques (sequencing of the 16S rRNA gene, DNA base ratio (% GC) determinations and DNA-DNA hybridisation) and phenotypic characterization. In the present paper, we propose a fast and reliable method for the identification most of the species currently described based on the RFLP-PCR of the 16S rRNA. According to the proposed protocol, 1 species can be identified with the use of a single enzyme, 13 with a combination of 2 enzymes, 2 species with a combination of 3 enzymes, 2 with a combination of 4 enzymes. To differentiate 5 more species RFLP-PCR of the ITS was also needed, after using 3 enzymes. Finally, a pair of species (Acetobacter pasteurianus and Acetobacter pomorum) could not be distinguished with the proposed method. However, doubts can be raised about their differentiation as separate species. Keeping these limitations in mind, the method is fast and reliable, allowing the processing of large number of samples in relatively short periods of time (less than 24 h after the isolation). PMID:16386324

  16. Diversity of acetic acid bacteria present in healthy grapes from the Canary Islands.

    PubMed

    Valera, Maria José; Laich, Federico; González, Sara S; Torija, Maria Jesús; Mateo, Estibaliz; Mas, Albert

    2011-11-15

    The identification of acetic acid bacteria (AAB) from sound grapes from the Canary Islands is reported in the present study. No direct recovery of bacteria was possible in the most commonly used medium, so microvinifications were performed on grapes from Tenerife, La Palma and Lanzarote islands. Up to 396 AAB were isolated from those microvinifications and identified by 16S rRNA gene sequencing and phylogenetic analysis. With this method, Acetobacter pasteurianus, Acetobacter tropicalis, Gluconobacter japonicus and Gluconacetobacter saccharivorans were identified. However, no discrimination between the closely related species Acetobacter malorum and Acetobacter cerevisiae was possible. As previously described, 16S-23S rRNA gene internal transcribed spacer (ITS) region phylogenetic analysis was required to classify isolates as one of those species. These two species were the most frequently occurring, accounting for more than 60% of the isolates. For typing the AAB isolates, both the Enterobacterial Repetitive Intergenic Consensus (ERIC)-PCR and (GTG)5-PCR techniques gave similar resolution. A total of 60 profiles were identified. Thirteen of these profiles were found in more than one vineyard, and only one profile was found on two different islands (Tenerife and La Palma). PMID:21903289

  17. Gluconobacter as well as Asaia species, newly emerging opportunistic human pathogens among acetic acid bacteria.

    PubMed

    Alauzet, Corentine; Teyssier, Corinne; Jumas-Bilak, Estelle; Gouby, Anne; Chiron, Raphael; Rabaud, Christian; Counil, François; Lozniewski, Alain; Marchandin, Hélène

    2010-11-01

    Acetic acid bacteria (AAB) are broadly used in industrial food processing. Among them, members of the genera Asaia, Acetobacter, and Granulibacter were recently reported to be human opportunistic pathogens. We isolated AAB from clinical samples from three patients and describe here the clinical and bacteriological features of these cases. We report for the first time (i) the isolation of a Gluconobacter sp. from human clinical samples; (ii) the successive isolation of different AAB, i.e., an Asaia sp. and two unrelated Gluconobacter spp., from a cystic fibrosis patient; and (iii) persistent colonization of the respiratory tract by a Gluconobacter sp. in this patient. We reviewed the main clinical features associated with AAB isolation identified in the 10 documented reports currently available in the literature. Albeit rare, infections as well as colonization with AAB are increasingly reported in patients with underlying chronic diseases and/or indwelling devices. Clinicians as well as medical microbiologists should be aware of these unusual opportunistic pathogens, which are difficult to detect during standard medical microbiological investigations and which are multiresistant to antimicrobial agents. Molecular methods are required for identification of genera of AAB, but the results may remain inconclusive for identification to the species level. PMID:20826638

  18. Rate Motifs Tune Auxin/Indole-3-Acetic Acid Degradation Dynamics1[OPEN

    PubMed Central

    Moss, Britney L.; Mao, Haibin; Guseman, Jessica M.; Hinds, Thomas R.; Hellmuth, Antje; Kovenock, Marlies; Noorassa, Anisa; Lanctot, Amy; Villalobos, Luz Irina A. Calderón; Zheng, Ning; Nemhauser, Jennifer L.

    2015-01-01

    Ubiquitin-mediated protein degradation is a common feature in diverse plant cell signaling pathways; however, the factors that control the dynamics of regulated protein turnover are largely unknown. One of the best-characterized families of E3 ubiquitin ligases facilitates ubiquitination of auxin (aux)/indole-3-acetic acid (IAA) repressor proteins in the presence of auxin. Rates of auxin-induced degradation vary widely within the Aux/IAA family, and sequences outside of the characterized degron (the minimum region required for auxin-induced degradation) can accelerate or decelerate degradation. We have used synthetic auxin degradation assays in yeast (Saccharomyces cerevisiae) and in plants to characterize motifs flanking the degron that contribute to tuning the dynamics of Aux/IAA degradation. The presence of these rate motifs is conserved in phylogenetically distant members of the Arabidopsis (Arabidopsis thaliana) Aux/IAA family, as well as in their putative Brassica rapa orthologs. We found that rate motifs can act by enhancing interaction between repressors and the E3, but that this is not the only mechanism of action. Phenotypes of transgenic plants expressing a deletion in a rate motif in IAA28 resembled plants expressing degron mutations, underscoring the functional relevance of Aux/IAA degradation dynamics in regulating auxin responses. PMID:26149575

  19. Tannic acid alleviates lead acetate-induced neurochemical perturbations in rat brain.

    PubMed

    Ashafaq, Mohammad; Tabassum, Heena; Vishnoi, Shruti; Salman, Mohd; Raisuddin, Sheikh; Parvez, Suhel

    2016-03-23

    Oxidative stress has been projected as a promising mechanism involved in lead exposure. The lead predisposition catalyzes oxidative reactions and generates reactive oxygen species. The present study was carried out to investigate the effect of oral administration of tannic acid (TA) on behavioral deficit, antioxidative deterioration induced by lead acetate (LA) exposure on experimental rat brain. Male Wistar rats were treated with 50mg/kg body weight of LA and TA for three times a week for two weeks. Our data showed LA-induced profound elevation of ROS production and oxidative stress, as evidenced by increased levels of oxidative stress markers such as lipid peroxidation and protein carbonyl observed in LA treated rats, whereas significant depletion in the activity of non-enzymatic antioxidants, enzymatic antioxidants, neurotoxicity biomarker and histological changes were observed in LA treated rat brain. However, TA administration restored antioxidant status of brain significantly when compared to control. Our results demonstrate that TA exhibits potent antioxidant properties and suppresses oxidative damages in rat brain induced by LA treatment. These findings were further supported by the neurotoxicity biomarker and histopathological findings in the brain tissue showed that TA protected tissue from deleterious effects of LA exposure. It is concluded, these data suggest that LA induces oxidative stress and supplementation of TA has a powerful antioxidant effect, and it protected rat brain from poisonous effect of LA exposure in experimental rat. PMID:26851560

  20. Seed and 4-chloroindole-3-acetic acid regulation of gibberellin metabolism in pea pericarp.

    PubMed Central

    van Huizen, R; Ozga, J A; Reinecke, D M; Twitchin, B; Mander, L N

    1995-01-01

    In this study, we investigated seed and auxin regulation of gibberellin (GA) biosynthesis in pea (Pisum sativum L.) pericarp tissue in situ, specifically the conversion of [14C]GA19 to [14C]GA20. [14C]GA19 metabolism was monitored in pericarp with seeds, deseeded pericarp, and deseeded pericarp treated with 4-chloroindole-3-acetic acid (4-CI-IAA). Pericarp with seeds and deseeded pericarp treated with 4-CI-IAA continued to convert [14C]GA19 to [14C]GA20 throughout the incubation period (2-24 h). However, seed removal resulted in minimal or no accumulation of [14C]GA20 in pericarp tissue. [14C]GA29 was also identified as a product of [14C]GA19 metabolism in pea pericarp. The ratio of [14C]GA29 to [14C]GA20 was significantly higher in deseeded pericarp (with or without exogenous 4-CI-IAA) than in pericarp with seeds. Therefore, conversion of [14C]GA20 to [14C]GA29 may also be seed regulated in pea fruit. These data support the hypothesis that the conversion of GA19 to GA20 in pea pericarp is seed regulated and that the auxin 4-CI-IAA can substitute for the seeds in the stimulation of pericarp growth and the conversion of GA19 to GA20. PMID:8539289

  1. A diverse assemblage of indole-3-acetic acid producing bacteria associate with unicellular green algae.

    PubMed

    Bagwell, Christopher E; Piskorska, Magdalena; Soule, Tanya; Petelos, Angela; Yeager, Chris M

    2014-08-01

    Microalgae have tremendous potential as a renewable feedstock for the production of liquid transportation fuels. In natural waters, the importance of physical associations and biochemical interactions between microalgae and bacteria is generally well appreciated, but the significance of these interactions to algal biofuels production have not been investigated. Here, we provide a preliminary report on the frequency of co-occurrence between indole-3-acetic acid (IAA)-producing bacteria and green algae in natural and engineered ecosystems. Growth experiments with unicellular algae, Chlorella and Scenedesmus, revealed IAA concentration-dependent responses in chlorophyll content and dry weight. Importantly, discrete concentrations of IAA resulted in cell culture synchronization, suggesting that biochemical priming of cellular metabolism could vastly improve the reliability of high density cultivation. Bacterial interactions may have an important influence on algal growth and development; thus, the preservation or engineered construction of the algal-bacterial assembly could serve as a control point for achieving low input, reliable production of algal biofuels. PMID:24879600

  2. Rate Motifs Tune Auxin/Indole-3-Acetic Acid Degradation Dynamics.

    PubMed

    Moss, Britney L; Mao, Haibin; Guseman, Jessica M; Hinds, Thomas R; Hellmuth, Antje; Kovenock, Marlies; Noorassa, Anisa; Lanctot, Amy; Villalobos, Luz Irina A Calderón; Zheng, Ning; Nemhauser, Jennifer L

    2015-09-01

    Ubiquitin-mediated protein degradation is a common feature in diverse plant cell signaling pathways; however, the factors that control the dynamics of regulated protein turnover are largely unknown. One of the best-characterized families of E3 ubiquitin ligases facilitates ubiquitination of auxin (aux)/indole-3-acetic acid (IAA) repressor proteins in the presence of auxin. Rates of auxin-induced degradation vary widely within the Aux/IAA family, and sequences outside of the characterized degron (the minimum region required for auxin-induced degradation) can accelerate or decelerate degradation. We have used synthetic auxin degradation assays in yeast (Saccharomyces cerevisiae) and in plants to characterize motifs flanking the degron that contribute to tuning the dynamics of Aux/IAA degradation. The presence of these rate motifs is conserved in phylogenetically distant members of the Arabidopsis (Arabidopsis thaliana) Aux/IAA family, as well as in their putative Brassica rapa orthologs. We found that rate motifs can act by enhancing interaction between repressors and the E3, but that this is not the only mechanism of action. Phenotypes of transgenic plants expressing a deletion in a rate motif in IAA28 resembled plants expressing degron mutations, underscoring the functional relevance of Aux/IAA degradation dynamics in regulating auxin responses. PMID:26149575

  3. Strain typing of acetic acid bacteria responsible for vinegar production by the submerged elaboration method.

    PubMed

    Fernández-Pérez, Rocío; Torres, Carmen; Sanz, Susana; Ruiz-Larrea, Fernanda

    2010-12-01

    Strain typing of 103 acetic acid bacteria isolates from vinegars elaborated by the submerged method from ciders, wines and spirit ethanol, was carried on in this study. Two different molecular methods were utilised: pulsed field gel electrophoresis (PFGE) of total DNA digests with a number of restriction enzymes, and enterobacterial repetitive intergenic consensus (ERIC) - PCR analysis. The comparative study of both methods showed that restriction fragment PFGE of SpeI digests of total DNA was a suitable method for strain typing and for determining which strains were present in vinegar fermentations. Results showed that strains of the species Gluconacetobacter europaeus were the most frequent leader strains of fermentations by the submerged method in the studied vinegars, and among them strain R1 was the predominant one. Results showed as well that mixed populations (at least two different strains) occurred in vinegars from cider and wine, whereas unique strains were found in spirit vinegars, which offered the most stressing conditions for bacterial growth. PMID:20832673

  4. Effects of glucose, ethanol and acetic acid on regulation of ADH2 gene from Lachancea fermentati.

    PubMed

    Yaacob, Norhayati; Mohamad Ali, Mohd Shukuri; Salleh, Abu Bakar; Abdul Rahman, Nor Aini

    2016-01-01

    Background. Not all yeast alcohol dehydrogenase 2 (ADH2) are repressed by glucose, as reported in Saccharomyces cerevisiae. Pichia stipitis ADH2 is regulated by oxygen instead of glucose, whereas Kluyveromyces marxianus ADH2 is regulated by neither glucose nor ethanol. For this reason, ADH2 regulation of yeasts may be species dependent, leading to a different type of expression and fermentation efficiency. Lachancea fermentati is a highly efficient ethanol producer, fast-growing cells and adapted to fermentation-related stresses such as ethanol and organic acid, but the metabolic information regarding the regulation of glucose and ethanol production is still lacking. Methods. Our investigation started with the stimulation of ADH2 activity from S. cerevisiae and L. fermentati by glucose and ethanol induction in a glucose-repressed medium. The study also embarked on the retrospective analysis of ADH2 genomic and protein level through direct sequencing and sites identification. Based on the sequence generated, we demonstrated ADH2 gene expression highlighting the conserved NAD(P)-binding domain in the context of glucose fermentation and ethanol production. Results. An increase of ADH2 activity was observed in starved L. fermentati (LfeADH2) and S. cerevisiae (SceADH2) in response to 2% (w/v) glucose induction. These suggest that in the presence of glucose, ADH2 activity was activated instead of being repressed. An induction of 0.5% (v/v) ethanol also increased LfeADH2 activity, promoting ethanol resistance, whereas accumulating acetic acid at a later stage of fermentation stimulated ADH2 activity and enhanced glucose consumption rates. The lack in upper stream activating sequence (UAS) and TATA elements hindered the possibility of Adr1 binding to LfeADH2. Transcription factors such as SP1 and RAP1 observed in LfeADH2 sequence have been implicated in the regulation of many genes including ADH2. In glucose fermentation, L. fermentati exhibited a bell-shaped ADH2

  5. Effects of glucose, ethanol and acetic acid on regulation of ADH2 gene from Lachancea fermentati

    PubMed Central

    Yaacob, Norhayati; Salleh, Abu Bakar; Abdul Rahman, Nor Aini

    2016-01-01

    Background. Not all yeast alcohol dehydrogenase 2 (ADH2) are repressed by glucose, as reported in Saccharomyces cerevisiae. Pichia stipitis ADH2 is regulated by oxygen instead of glucose, whereas Kluyveromyces marxianus ADH2 is regulated by neither glucose nor ethanol. For this reason, ADH2 regulation of yeasts may be species dependent, leading to a different type of expression and fermentation efficiency. Lachancea fermentati is a highly efficient ethanol producer, fast-growing cells and adapted to fermentation-related stresses such as ethanol and organic acid, but the metabolic information regarding the regulation of glucose and ethanol production is still lacking. Methods. Our investigation started with the stimulation of ADH2 activity from S. cerevisiae and L. fermentati by glucose and ethanol induction in a glucose-repressed medium. The study also embarked on the retrospective analysis of ADH2 genomic and protein level through direct sequencing and sites identification. Based on the sequence generated, we demonstrated ADH2 gene expression highlighting the conserved NAD(P)-binding domain in the context of glucose fermentation and ethanol production. Results. An increase of ADH2 activity was observed in starved L. fermentati (LfeADH2) and S. cerevisiae (SceADH2) in response to 2% (w/v) glucose induction. These suggest that in the presence of glucose, ADH2 activity was activated instead of being repressed. An induction of 0.5% (v/v) ethanol also increased LfeADH2 activity, promoting ethanol resistance, whereas accumulating acetic acid at a later stage of fermentation stimulated ADH2 activity and enhanced glucose consumption rates. The lack in upper stream activating sequence (UAS) and TATA elements hindered the possibility of Adr1 binding to LfeADH2. Transcription factors such as SP1 and RAP1 observed in LfeADH2 sequence have been implicated in the regulation of many genes including ADH2. In glucose fermentation, L. fermentati exhibited a bell-shaped ADH2

  6. The short-chain fatty acid acetate reduces appetite via a central homeostatic mechanism.

    PubMed

    Frost, Gary; Sleeth, Michelle L; Sahuri-Arisoylu, Meliz; Lizarbe, Blanca; Cerdan, Sebastian; Brody, Leigh; Anastasovska, Jelena; Ghourab, Samar; Hankir, Mohammed; Zhang, Shuai; Carling, David; Swann, Jonathan R; Gibson, Glenn; Viardot, Alexander; Morrison, Douglas; Louise Thomas, E; Bell, Jimmy D

    2014-01-01

    Increased intake of dietary carbohydrate that is fermented in the colon by the microbiota has been reported to decrease body weight, although the mechanism remains unclear. Here we use in vivo(11)C-acetate and PET-CT scanning to show that colonic acetate crosses the blood-brain barrier and is taken up by the brain. Intraperitoneal acetate results in appetite suppression and hypothalamic neuronal activation patterning. We also show that acetate administration is associated with activation of acetyl-CoA carboxylase and changes in the expression profiles of regulatory neuropeptides that favour appetite suppression. Furthermore, we demonstrate through (13)C high-resolution magic-angle-spinning that (13)C acetate from fermentation of (13)C-labelled carbohydrate in the colon increases hypothalamic (13)C acetate above baseline levels. Hypothalamic (13)C acetate regionally increases the (13)C labelling of the glutamate-glutamine and GABA neuroglial cycles, with hypothalamic (13)C lactate reaching higher levels than the 'remaining brain'. These observations suggest that acetate has a direct role in central appetite regulation. PMID:24781306

  7. The short-chain fatty acid acetate reduces appetite via a central homeostatic mechanism

    PubMed Central

    Frost, Gary; Sleeth, Michelle L.; Sahuri-Arisoylu, Meliz; Lizarbe, Blanca; Cerdan, Sebastian; Brody, Leigh; Anastasovska, Jelena; Ghourab, Samar; Hankir, Mohammed; Zhang, Shuai; Carling, David; Swann, Jonathan R.; Gibson, Glenn; Viardot, Alexander; Morrison, Douglas; Louise Thomas, E; Bell, Jimmy D.

    2014-01-01

    Increased intake of dietary carbohydrate that is fermented in the colon by the microbiota has been reported to decrease body weight, although the mechanism remains unclear. Here we use in vivo11C-acetate and PET-CT scanning to show that colonic acetate crosses the blood–brain barrier and is taken up by the brain. Intraperitoneal acetate results in appetite suppression and hypothalamic neuronal activation patterning. We also show that acetate administration is associated with activation of acetyl-CoA carboxylase and changes in the expression profiles of regulatory neuropeptides that favour appetite suppression. Furthermore, we demonstrate through 13C high-resolution magic-angle-spinning that 13C acetate from fermentation of 13C-labelled carbohydrate in the colon increases hypothalamic 13C acetate above baseline levels. Hypothalamic 13C acetate regionally increases the 13C labelling of the glutamate–glutamine and GABA neuroglial cycles, with hypothalamic 13C lactate reaching higher levels than the ‘remaining brain’. These observations suggest that acetate has a direct role in central appetite regulation. PMID:24781306

  8. Exogenous malic and acetic acids reduce cadmium phytotoxicity and enhance cadmium accumulation in roots of sunflower plants.

    PubMed

    Hawrylak-Nowak, Barbara; Dresler, Sławomir; Matraszek, Renata

    2015-09-01

    There is increasing evidence showing that low molecular weight organic acids (LMWOA) are involved in heavy metal resistance mechanisms in plants. The aim of this study was to investigate the effects of exogenous malic (MA) or acetic (AA) acids on the toxicity and accumulation of cadmium (Cd) in sunflower (Helianthus annuus L.). For this purpose, plants were grown in hydroponics under controlled conditions. Single Cd stress (5 μM Cd for 14 days) induced strong phytotoxic effects, as indicated by a decrease in all growth parameters, concentration of photosynthetic pigments, and root activity, as well as a high level of hydrogen peroxide (H2O2) accumulation. Exogenous MA or AA (250 or 500 μM) applied to the Cd-containing medium enhanced the accumulation of Cd by the roots and limited Cd translocation to the shoots. Moreover, the MA or AA applied more or less reduced Cd phytotoxicity by increasing the growth parameters, photosynthetic pigment concentrations, decreasing accumulation of H2O2, and improving the root activity. Of the studied organic acids, MA was much more efficient in mitigation of Cd toxicity than AA, probably by its antioxidant effects, which were stronger than those of AA. Plant response to Cd involved decreased production of endogenous LMWOA, probably as a consequence of severe Cd toxicity. The addition of MA or AA to the medium increased endogenous accumulation of LMWOA, especially in the roots, which could be beneficial for plant metabolism. These results imply that especially MA may be involved in the processes of Cd uptake, translocation, and tolerance in plants. PMID:26115548

  9. A comparison of gamma-aminobutyric acid and the semi-rigid analogues 4-aminotetrolic acid, 4-aminocrotonic acid and imidazole-4-acetic acid on the isolated superior cervical ganglion of the rat.

    PubMed Central

    Bowery, N G; Jones, G P

    1976-01-01

    1 The rat superior cervical ganglion possesses receptors for gamma-aminobutyric acid (GABA). This can be demonstrated in vitro by recording the changes in ganglionic surface potential which occur after the addition of GABA to the bathing solution. 2 The action of three conformationally-restricted analogues of GABA namely 4-aminotetrolic acid (4-ATA), trans 4-aminocrotonic acid (4-ACA) and imidazole-4-acetic acid (IAA) have been examined for activity at this peripheral receptor. 3 All three analogues depolarized the ganglion in a manner similar to GABA. Their actions were transient and were 'occluded' by GABA; also the dose-response curve in each case was parallel to that of GABA. Molar potencies relative to GABA (= 1) were 4-ACA = 1.48, IAA = 0.100, 4-ATA = 0.0028. 4 The action of each analogue could be blocked by the GABA antagonists bicuculline and tetramethylenedisulphotetramine at doses which had relatively little effect on responses to the cholinomimetic carbachol. 5 4-ACA and IAA (1 mM) significantly reduced the ganglionic accumulation of [3H]-GABA (0.2 muM) by 88% and 58% respectively whereas 4-ATA (1 mM), caused no significant reduction in [3H]-GABA accumulation. PMID:1260178

  10. Pharmacokinetic-pharmacodynamic modelling of the convulsant interaction between norfloxacin and biphenyl acetic acid in rats.

    PubMed

    Marchand, S; Pariat, C; Bouquet, S; Courtois, P; Couet, W

    2000-04-01

    Fluoroquinolones (FQs) are associated with a low incidence of central nervous system (CNS) side effects, possibly leading to convulsions, especially when co-administered with nonsteroidal anti-inflammatory drugs (NSAIDS). Although the in vivo pro-convulsant activity of NSAIDS is essentially unknown, the convulsant potential of FQs is traditionally evaluated by in vitro gamma-aminobutyric acid (GABA) binding experiments in the presence of 4-biphenyl acetic acid (BPAA), the active metabolite of fenbufen. The aim of this study was therefore to investigate the BPAA-norfloxacin convulsant interaction in vivo. Male Sprague-Dawley rats (n = 27) were given BPAA orally, at various doses 1 h before norfloxacin infusion, which was maintained until the onset of maximal seizures, when cerebrospinal fluid (CSF) and plasma samples were collected for analysis. An inhibitory E(max) effect model with a baseline effect parameter was fitted to the norfloxacin versus BPAA concentrations in the CSF, previously shown to be part of the biophase. This model includes three parameters: the concentrations of norfloxacin in the absence of BPAA (C(CSF0, Nor)), and when BPAA concentration tends toward infinity (C(CSFbase, Nor)), and the BPAA concentration for which half of the maximal effect is observed (C(CSF50, BPAA)). The maximal proconvulsant effect of BPAA is given by the C(CSF0, Nor) / C(CSFbase, Nor) ratio, estimated to approximately 6 in this study. Derived models were developed in plasma to account for the non-linear CSF diffusion of norfloxacin and protein binding of BPAA. In conclusion this study has shown that the convulsant interaction between norfloxacin and BPAA in rats, can be adequately characterized by modelling of the CSF concentrations of the two drugs at the onset of activity, following their administration in various proportions. PMID:10780965

  11. Pharmacokinetic-pharmacodynamic modelling of the convulsant interaction between norfloxacin and biphenyl acetic acid in rats

    PubMed Central

    Marchand, Sandrine; Pariat, Claudine; Bouquet, Serge; Courtois, Philippe; Couet, William

    2000-01-01

    Fluoroquinolones (FQs) are associated with a low incidence of central nervous system (CNS) side effects, possibly leading to convulsions, especially when co-administered with nonsteroidal anti-inflammatory drugs (NSAIDS). Although the in vivo pro-convulsant activity of NSAIDS is essentially unknown, the convulsant potential of FQs is traditionally evaluated by in vitro γ-aminobutyric acid (GABA) binding experiments in the presence of 4-biphenyl acetic acid (BPAA), the active metabolite of fenbufen.The aim of this study was therefore to investigate the BPAA-norfloxacin convulsant interaction in vivo.Male Sprague-Dawley rats (n=27) were given BPAA orally, at various doses 1 h before norfloxacin infusion, which was maintained until the onset of maximal seizures, when cerebrospinal fluid (CSF) and plasma samples were collected for analysis.An inhibitory Emax effect model with a baseline effect parameter was fitted to the norfloxacin versus BPAA concentrations in the CSF, previously shown to be part of the biophase. This model includes three parameters: the concentrations of norfloxacin in the absence of BPAA (CCSF0, Nor), and when BPAA concentration tends toward infinity (CCSFbase, Nor), and the BPAA concentration for which half of the maximal effect is observed (CCSF50, BPAA). The maximal proconvulsant effect of BPAA is given by the CCSF0, Nor / CCSFbase, Nor ratio, estimated to approximately 6 in this study.Derived models were developed in plasma to account for the non-linear CSF diffusion of norfloxacin and protein binding of BPAA.In conclusion this study has shown that the convulsant interaction between norfloxacin and BPAA in rats, can be adequately characterized by modelling of the CSF concentrations of the two drugs at the onset of activity, following their administration in various proportions. PMID:10780965

  12. Biofilm formation and indole-3-acetic acid production by two rhizospheric unicellular cyanobacteria.

    PubMed

    Ahmed, Mehboob; Stal, Lucas J; Hasnain, Shahida

    2014-08-01

    Microorganisms that live in the rhizosphere play a pivotal role in the functioning and maintenance of soil ecosystems. The study of rhizospheric cyanobacteria has been hampered by the difficulty to culture and maintain them in the laboratory. The present work investigated the production of the plant hormone indole-3-acetic acid (IAA) and the potential of biofilm formation on the rhizoplane of pea plants by two cyanobacterial strains, isolated from rice rhizosphere. The unicellular cyanobacteria Chroococcidiopsis sp. MMG-5 and Synechocystis sp. MMG-8 that were isolated from a rice rhizosphere, were investigated. Production of IAA by Chroococcidiopsis sp. MMG-5 and Synechocystis sp. MMG-8 was measured under experimental conditions (pH and light). The bioactivity of the cyanobacterial auxin was demonstrated through the alteration of the rooting pattern of Pisum sativum seedlings. The increase in the concentration of L-tryptophan and the time that this amino acid was present in the medium resulted in a significant enhancement of the synthesis of IAA (r > 0.900 at p = 0.01). There was also a significant correlation between the concentration of IAA in the supernatant of the cyanobacteria cultures and the root length and number of the pea seedlings. Observations made by confocal laser scanning microscopy revealed the presence of cyanobacteria on the surface of the roots and also provided evidence for the penetration of the cyanobacteria in the endorhizosphere. We show that the synthesis of IAA by Chroococcidiopsis sp. MMG-5 and Synechocystis sp. MMG-8 occurs under different environmental conditions and that the auxin is important for the development of the seedling roots and for establishing an intimate symbiosis between cyanobacteria and host plants. PMID:24705871

  13. Exchange of atmospheric formic and acetic acids with trees and crop plants under controlled chamber and purified air conditions

    NASA Astrophysics Data System (ADS)

    Kesselmeier, J.; Bode, K.; Gerlach, C.; Jork, E.-M.

    We investigated the exchange of formic and acetic acids between the atmosphere and various tree species such as beech ( Fagus sylvatica L.), ash ( Fraxinus excelsior L.), spruce ( Picea abies L.) Karst, holm oak ( Quercus ilex L.), and birch ( Betula pendula L.). and some crop-plant species such as corn ( Zea mays, var. Banjo), pea ( Pisum sativum, var. Solara), barley ( Hordeum vulgare, var. Igri) and oat (Avena sativa, var. Wiesel). All experiments were done with dynamic enclosures flushed with purified oxidant-free air, containing only low or controlled amounts of the two acids. Significant and light-triggered emission of both acids from all tree species was observed. For one tree species (ash) a seasonal large increase in fall due to early leaf decomposition was found. The standard emission factors (30°C and PAR=1000 μmol m 2 s -1) given as (nmol m -2 min -1) for acetic and formic acids, respectively, were 8.1 and 29.7 (ash, autumn), 1.0 and 3.3 (ash, summer), 0.9 and 1.4 (beech), 0.7 and 1.45 (spruce), 1.9 and 2.4 (Holm oak) and 1.7 and 6.7 (birch). Rough estimation of global annual emissions range between 20 and 130 Gmol formic acid and 10 and 33 Gmol acetic acid. These numbers reflect a 15-30% contribution by forest emissions to the continental organic acid budget. As compared to the global total NMHC emissions low molecular weight organic acids are of minor importance. In contrast to the trees, none of the crop-plant species investigated showed an emission, but always a clear deposition of both acids. Both emission from trees as well as uptake by the agricultural plants could be related to transpiration rates and leaf conductances.

  14. Additive for electrolyte of lead-acid batteries

    SciTech Connect

    Greene, R.M.

    1986-10-14

    This patent describes a lead-acid storage battery containing as an electrolyte for each cell, an aqueous sulfuric acid solution containing an activating amount of an additive comprising a mixture of an iron chelate and a magnesium salt or chelate. The chelates for the iron and magnesium are formed from the chelating agents which form 4 to 6 membered rings with the iron and magnesium and which contain a member of the group consisting of amine groups, phenol groups and aldehyde groups.

  15. Influence of an acetate- and a lactate-based balanced infusion solution on acid base physiology and hemodynamics: an observational pilot study

    PubMed Central

    2012-01-01

    Background The current pilot study compares the impact of an intravenous infusion of Ringer’s lactate to an acetate-based solution with regard to acid–base balance. The study design included the variables of the Stewart approach and focused on the effective strong ion difference. Because adverse hemodynamic effects have been reported when using acetate buffered solutions in hemodialysis, hemodynamics were also evaluated. Methods Twenty-four women who had undergone abdominal gynecologic surgery and who had received either Ringer’s lactate (Strong Ion Difference 28 mmol/L; n = 12) or an acetate-based solution (Strong Ion Difference 36.8 mmol/L; n = 12) according to an established clinical protocol and its precursor were included in the investigation. After induction of general anesthesia, a set of acid–base variables, hemodynamic values and serum electrolytes was measured three times during the next 120 minutes. Results Patients received a mean dose of 4,054 ± 450 ml of either one or the other of the solutions. In terms of mean arterial blood pressure and norepinephrine requirements there were no differences to observe between the study groups. pH and serum HCO3- concentration decreased slightly but significantly only with Ringer’s lactate. In addition, the acetate-based solution kept the plasma effective strong ion difference more stable than Ringer’s lactate. Conclusions Both of the solutions provided hemodynamic stability. Concerning consistency of acid base parameters none of the solutions seemed to be inferior, either. Whether the slight advantages observed for the acetate-buffered solution in terms of stability of pH and plasma HCO3- are clinically relevant, needs to be investigated in a larger randomized controlled trial. PMID:22769740

  16. Kinetics of cytochrome P450 2E1-catalyzed oxidation of ethanol to acetic acid via acetaldehyde.

    PubMed

    Bell-Parikh, L C; Guengerich, F P

    1999-08-20

    The P450 2E1-catalyzed oxidation of ethanol to acetaldehyde is characterized by a kinetic deuterium isotope effect that increases K(m) with no effect on k(cat), and rate-limiting product release has been proposed to account for the lack of an isotope effect on k(cat) (Bell, L. C., and Guengerich, F. P. (1997) J. Biol. Chem. 272, 29643-29651). Acetaldehyde is also a substrate for P450 2E1 oxidation to acetic acid, and k(cat)/K(m) for this reaction is at least 1 order of magnitude greater than that for ethanol oxidation to acetaldehyde. Acetic acid accounts for 90% of the products generated from ethanol in a 10-min reaction, and the contribution of this second oxidation has been overlooked in many previous studies. The noncompetitive intermolecular kinetic hydrogen isotope effects on acetaldehyde oxidation to acetic acid ((H)(k(cat)/K(m))/(D)(k(cat)/K(m)) = 4.5, and (D)k(cat) = 1.5) are comparable with the isotope effects typically observed for ethanol oxidation to acetaldehyde, and k(cat) is similar for both reactions, suggesting a possible common catalytic mechanism. Rapid quench kinetic experiments indicate that acetic acid is formed rapidly from added acetaldehyde (approximately 450 min(-1)) with burst kinetics. Pulse-chase experiments reveal that, at a subsaturating concentration of ethanol, approximately 90% of the acetaldehyde intermediate is directly converted to acetic acid without dissociation from the enzyme active site. Competition experiments suggest that P450 2E1 binds acetic acid and acetaldehyde with relatively high K(d) values, which preclude simple tight binding as an explanation for rate-limiting product release. The existence of a rate-determining step between product formation and release is postulated. Also proposed is a conformational change in P450 2E1 occurring during the course of oxidation and the discrimination of P450 2E1 between acetaldehyde and its hydrated form, the gem-diol. This multistep P450 reaction is characterized by kinetic

  17. Recycling acetic acid from polarizing film of waste liquid crystal display panels by sub/supercritical water treatments.

    PubMed

    Wang, Ruixue; Chen, Ya; Xu, Zhenming

    2015-05-19

    Waste liquid crystal display (LCD) panels mainly contain inorganic materials (glass substrate) and organic materials (polarizing film and liquid crystal). The organic materials should be removed first since containing polarizing film and liquid crystal is to the disadvantage of the indium recycling process. In the present study, an efficient and environmentally friendly process to obtain acetic acid from waste LCD panels by sub/supercritical water treatments is investigated. Furthermore, a well-founded reaction mechanism is proposed. Several highlights of this study are summarized as follows: (i) 99.77% of organic matters are removed, which means the present technology is quite efficient to recycle the organic matters; (ii) a yield of 78.23% acetic acid, a quite important fossil energy based chemical product is obtained, which can reduce the consumption of fossil energy for producing acetic acid; (iii) supercritical water acts as an ideal solvent, a requisite reactant as well as an efficient acid-base catalyst, and this is quite significant in accordance with the "Principles of Green Chemistry". In a word, the organic matters of waste LCD panels are recycled without environmental pollution. Meanwhile, this study provides new opportunities for alternating fossil-based chemical products for sustainable development, converting "waste" into "fossil-based chemicals". PMID:25915068

  18. A rapid hydrolysis method and DABS-Cl derivatization for complete amino acid analysis of octreotide acetate by reversed phase HPLC.

    PubMed

    Akhlaghi, Yousef; Ghaffari, Solmaz; Attar, Hossein; Alamir Hoor, Amir

    2015-11-01

    Octreotide as a synthetic cyclic octapeptide is a somatostatin analog with longer half-life and more selectivity for inhibition of the growth hormone. The acetate salt of octreotide is currently used for medical treatment of somatostatin-related disorders such as endocrine and carcinoid tumors, acromegaly, and gigantism. Octreotide contains both cysteine and tryptophan residues which make the hydrolysis part of its amino acid analysis procedure very challenging. The current paper introduces a fast and additive-free method which preserves tryptophan and cysteine residues during the hydrolysis. Using only 6 M HCl, this hydrolysis process is completed in 30 min at 150 °C. This fast hydrolysis method followed by pre-column derivatization of the released amino acids with 4-N,N-dimethylaminoazobenzene-4'-sulfonyl chloride (DABS-Cl) which takes only 20 min, makes it possible to do the complete amino acid analysis of an octreotide sample in a few hours. The highly stable-colored DABS-Cl derivatives can be detected in 436 nm in a reversed phase chromatographic system, which eliminates spectral interferences to a great extent. The amino acid analysis of octreotide acetate including hydrolysis, derivatization, and reversed phase HPLC determination was validated according to International Conference of Harmonization (ICH) guidelines. PMID:26002809

  19. Replacement of a terminal cytochrome c oxidase by ubiquinol oxidase during the evolution of acetic acid bacteria.

    PubMed

    Matsutani, Minenosuke; Fukushima, Kota; Kayama, Chiho; Arimitsu, Misato; Hirakawa, Hideki; Toyama, Hirohide; Adachi, Osao; Yakushi, Toshiharu; Matsushita, Kazunobu

    2014-10-01

    The bacterial aerobic respiratory chain has a terminal oxidase of the heme-copper oxidase superfamily, comprised of cytochrome c oxidase (COX) and ubiquinol oxidase (UOX); UOX evolved from COX. Acetobacter pasteurianus, an α-Proteobacterial acetic acid bacterium (AAB), produces UOX but not COX, although it has a partial COX gene cluster, ctaBD and ctaA, in addition to the UOX operon cyaBACD. We expressed ctaB and ctaA genes of A. pasteurianus in Escherichia coli and demonstrated their function as heme O and heme A synthases. We also found that the absence of ctaD function is likely due to accumulated mutations. These COX genes are closely related to other α-Proteobacterial COX proteins. However, the UOX operons of AAB are closely related to those of the β/γ-Proteobacteria (γ-type UOX), distinct from the α/β-Proteobacterial proteins (α-type UOX), but different from the other γ-type UOX proteins by the absence of the cyoE heme O synthase. Thus, we suggest that A. pasteurianus has a functional γ-type UOX but has lost the COX genes, with the exception of ctaB and ctaA, which supply the heme O and A moieties for UOX. Our results suggest that, in AAB, COX was replaced by β/γ-Proteobacterial UOX via horizontal gene transfer, while the COX genes, except for the heme O/A synthase genes, were lost. PMID:24862920

  20. Biosynthesis and Secretion of Indole-3-Acetic Acid and Its Morphological Effects on Tricholoma vaccinum-Spruce Ectomycorrhiza.

    PubMed

    Krause, Katrin; Henke, Catarina; Asiimwe, Theodore; Ulbricht, Andrea; Klemmer, Sandra; Schachtschabel, Doreen; Boland, Wilhelm; Kothe, Erika

    2015-10-01

    Fungus-derived indole-3-acetic acid (IAA), which is involved in development of ectomycorrhiza, affects both partners, i.e., the tree and the fungus. The biosynthesis pathway, excretion from fungal hyphae, the induction of branching in fungal cultures, and enhanced Hartig net formation in mycorrhiza were shown. Gene expression studies, incorporation of labeled compounds into IAA, heterologous expression of a transporter, and bioinformatics were applied to study the effect of IAA on fungal morphogenesis and on ectomycorrhiza. Tricholoma vaccinum produces IAA from tryptophan via indole-3-pyruvate, with the last step of this biosynthetic pathway being catalyzed by an aldehyde dehydrogenase. The gene ald1 was found to be highly expressed in ectomycorrhiza and induced by indole-3-acetaldehyde. The export of IAA from fungal cells is supported by the multidrug and toxic extrusion (MATE) transporter Mte1 found in T. vaccinum. The addition of IAA and its precursors induced elongated cells and hyphal ramification of mycorrhizal fungi; in contrast, in saprobic fungi such as Schizophyllum commune, IAA did not induce morphogenetic changes. Mycorrhiza responded by increasing its Hartig net formation. The IAA of fungal origin acts as a diffusible signal, influencing root colonization and increasing Hartig net formation in ectomycorrhiza. PMID:26231639

  1. New insights into the role of indole-3-acetic acid in the virulence of Pseudomonas savastanoi pv. savastanoi.

    PubMed

    Aragón, Isabel M; Pérez-Martínez, Isabel; Moreno-Pérez, Alba; Cerezo, Miguel; Ramos, Cayo

    2014-07-01

    Indole-3-acetic acid (IAA) is a widespread phytohormone among plant-associated bacteria, including the tumour-inducing pathogen of woody hosts, Pseudomonas savastanoi pv. savastanoi. A phylogenetic analysis of the iaaM/iaaH operon, which is involved in the biosynthesis of IAA, showed that one of the two operons encoded by Pseudomonas savastanoi pv. savastanoi NCPPB 3335, iaaM-1/iaaH-1, is horizontally transferred among bacteria belonging to the Pseudomonas syringae complex. We also show that biosynthesis of the phytohormone, virulence and full fitness of this olive pathogen depend only on the functionality of the iaaM-1/iaaH-1 operon. In contrast, the iaaM-2/iaaH-2 operon, which carries a 22-nt insertion in the iaaM-2 gene, does not contribute to the production of IAA by this bacterium. A residual amount of IAA was detected in the culture supernatants of a double mutant affected in both iaaM/iaaH operons, suggesting that a different pathway might also contribute to the total pool of the phytohormone produced by this pathogen. Additionally, we show that exogenously added IAA negatively and positively regulates the expression of genes related to the type III and type VI secretion systems, respectively. Together, these results suggest a role of IAA as a signalling molecule in this pathogen. PMID:24606017

  2. Biosynthesis and Secretion of Indole-3-Acetic Acid and Its Morphological Effects on Tricholoma vaccinum-Spruce Ectomycorrhiza

    PubMed Central

    Krause, Katrin; Henke, Catarina; Asiimwe, Theodore; Ulbricht, Andrea; Klemmer, Sandra; Schachtschabel, Doreen; Boland, Wilhelm

    2015-01-01

    Fungus-derived indole-3-acetic acid (IAA), which is involved in development of ectomycorrhiza, affects both partners, i.e., the tree and the fungus. The biosynthesis pathway, excretion from fungal hyphae, the induction of branching in fungal cultures, and enhanced Hartig net formation in mycorrhiza were shown. Gene expression studies, incorporation of labeled compounds into IAA, heterologous expression of a transporter, and bioinformatics were applied to study the effect of IAA on fungal morphogenesis and on ectomycorrhiza. Tricholoma vaccinum produces IAA from tryptophan via indole-3-pyruvate, with the last step of this biosynthetic pathway being catalyzed by an aldehyde dehydrogenase. The gene ald1 was found to be highly expressed in ectomycorrhiza and induced by indole-3-acetaldehyde. The export of IAA from fungal cells is supported by the multidrug and toxic extrusion (MATE) transporter Mte1 found in T. vaccinum. The addition of IAA and its precursors induced elongated cells and hyphal ramification of mycorrhizal fungi; in contrast, in saprobic fungi such as Schizophyllum commune, IAA did not induce morphogenetic changes. Mycorrhiza responded by increasing its Hartig net formation. The IAA of fungal origin acts as a diffusible signal, influencing root colonization and increasing Hartig net formation in ectomycorrhiza. PMID:26231639

  3. Multifunctional Pd/Ni-Co catalyst for hydrogen production by chemical looping coupled with steam reforming of acetic acid.

    PubMed

    Fermoso, Javier; Gil, María V; Rubiera, Fernando; Chen, De

    2014-11-01

    High yield of high-purity H2 from acetic acid, a model compound of bio-oil obtained from the fast pyrolysis of biomass, was produced by sorption-enhanced steam reforming (SESR). An oxygen carrier was introduced into a chemical loop (CL) coupled to the cyclical SESR process to supply heat in situ for the endothermic sorbent regeneration to increase the energy efficiency of the process. A new multifunctional 1 %Pd/20 %Ni-20 %Co catalyst was developed for use both as oxygen carrier in the CL and as reforming catalyst in the SESR whereas a CaO-based material was used as CO2 sorbent. In the sorbent-air regeneration step, the Ni-Co atoms in the catalyst undergo strong exothermic oxidation reactions that provide heat for the CaO decarbonation. The addition of Pd to the Ni-Co catalyst makes the catalyst active throughout the whole SESR-CL cycle. Pd significantly promotes the reduction of Ni-Co oxides to metallic Ni-Co during the reforming stage, which avoids the need for a reduction step after regeneration. H2 yield above 90 % and H2 purity above 99.2 vol % were obtained. PMID:25209388

  4. Pretreatment of Gymnema sylvestre revealed the protection against acetic acid-induced ulcerative colitis in rats

    PubMed Central

    2014-01-01

    Background Overproduction of free radicals and decreased antioxidant capacity are well-known risk factors for inflammatory bowel diseases. Gymnema sylvestre (GS) leaves extract is distinguished for its anti-diabetic, antioxidant and anti-inflammatory properties. Present study is designed to evaluate the preventative activities of GS against acetic acid (AA)-induced ulcerative colitis in Wistar rats. Methods Experimentally ulcerative colitis (UC) was induced by AA in animals pretreated with three different doses of GS leaves extract (50, 100, 200 mg/kg/day) and a single dose of mesalazine (MES, 300 mg/kg/day) for seven days. Twenty four hours later, animals were sacrificed and the colonic tissues were collected. Colonic mucus content was determined using Alcian blue dye binding technique. Levels of thiobarbituric acid reactive substances (TBARS), total glutathione sulfhydryl group (T-GSH) and non-protein sulfhydryl group (NPSH) as well as the activity of the antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) were estimated in colon tissues. Colonic nucleic acids (DNA and RNA) and total protein (TP) concentrations were also determined. Levels of pro-inflammatory cytokines including interleukin-1 beta (IL-1β), tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) as well as prostaglandin E2 (PGE2) and nitric oxide (NO) were estimated in colonic tissues. The histopathological changes of the colonic tissues were also observed. Results In AA administered group TBARS levels were increased, while colonic mucus content, T-GSH and NP-SH, SOD and CAT were reduced in colon. Pretreatment with GS inhibited TBARS elevation as well as mucus content, T-GSH and NP-SH reduction. Enzymatic activities of SOD and CAT were brought back to their normal levels in GS pretreated group. A significant reduction in DNA, RNA and TP levels was seen following AA administration and this inhibition was significantly eliminated by GS treatment. GS pretreatment also inhibited

  5. Effects of indole-3-acetic acid on Botrytis cinerea isolates obtained from potted plants.

    PubMed

    Martínez, J A; Valdés, R; Gómez-Bellot, M J; Bañón, S

    2011-01-01

    We study the growth of different isolates of Botrytis cinerea collected from potted plants which were affected by Botrytis blight in southern Spain during recent years. These isolates, which show widely phenotypic differences when grown in vitro, are differentially affected by growth temperature, gibberellic acid applications and paclobutrazol, an efficient plant growth retardant and fungicide at the same time. In this work, we have evaluated the effect of the auxin indole-3-acetic acid (IAA) dose (0, 1, 10, and 100 mg/plate) on the growth of the collection of B. cinerea isolates obtained from the following potted plants: Cyclamen persicum, Hydrangea macrophylla, Lantona camara, and Lonicera japonica. B. cinerea produces indolacetic acid, but so far the precise biosynthetic pathway and some effects on this fungal species are still unclear, although recent studies have revealed an antifungal activity of IAA on several fungi, including B. cinerea isolated from harvested fruits. Mycelial growth curves and growth rates assessed from difference in colony areas during the both linear and deceleration phase, conidiation (measured as time of appearance), conidia length (microm), and sclerotia production (number/plate) were evaluated in the isolates, which were grown at 26 degrees C on Petri dishes containing potato dextrose agar for up to 35 days. Mycelial growth curves fitted a typical kinetic equation of fungi grown on solid media. B. cinerea isolates showed a high degree of variability in their growth kinetics, depending on the isolate and auxin dose. This plant growth substance delayed mycelial growth during the linear phase in an isolate-dependent manner, thus isolates from C. persicum, H. macrophylla and L. camara were more affected by IAA than L. japonica. On the other hand, 100 mg of IAA was the critical dose to significantly reduce the growth rate in all isolates and to promote brown-striped hyphae development, especially in isolate from C. persicum. 10 and 100 mg

  6. Monitoring of substrate and product concentrations in acetic fermentation processes for onion vinegar production by NIR spectroscopy: value addition to worthless onions.

    PubMed

    González-Sáiz, J M; Esteban-Díez, I; Sánchez-Gallardo, C; Pizarro, C

    2008-08-01

    Wastes and by-products of the onion-processing industry pose an increasing disposal and environmental problem and represent a loss of valuable sources of nutrients. The present study focused on the production of vinegar from worthless onions as a potential valorisation route which could provide a viable solution to multiple disposal and environmental problems, simultaneously offering the possibility of converting waste materials into a useful food-grade product and of exploiting the unique properties and health benefits of onions. This study deals specifically with the second and definitive step of the onion vinegar production process: the efficient production of vinegar from onion waste by transforming onion ethanol, previously produced by alcoholic fermentation, into acetic acid via acetic fermentation. Near-infrared spectroscopy (NIRS), coupled with multivariate calibration methods, has been used to monitor the concentrations of both substrates and products in acetic fermentation. Separate partial least squares (PLS) regression models, correlating NIR spectral data of fermentation samples with each kinetic parameter studied, were developed. Wavelength selection was also performed applying the iterative predictor weighting-PLS (IPW-PLS) method in order to only consider significant spectral features in each model development to improve the quality of the final models constructed. Biomass, substrate (ethanol) and product (acetic acid) concentration were predicted in the acetic fermentation of onion alcohol with high accuracy using IPW-PLS models with a root-mean-square error of the residuals in external prediction (RMSEP) lower than 2.5% for both ethanol and acetic acid, and an RMSEP of 6.1% for total biomass concentration (a very satisfactory result considering the relatively low precision and accuracy associated with the reference method used for determining the latter). Thus, the simple and reliable calibration models proposed in this study suggest that they

  7. Recovery of acetic acid from pre-hydrolysis liquor of hardwood kraft-based dissolving pulp production process by reactive extraction with triisooctylamine.

    PubMed

    Yang, G; Jahan, M Sarwar; Ahsan, Laboni; Zheng, Linqiang; Ni, Yonghao

    2013-06-01

    Acetic acid was one of the main compositions of the pre-hydrolysis liquor (PHL), which was recovered by reactive extraction with triisooctylamine (TIOA) diluted with decanol. Dilution of TIOA played an important role in extracting acetic acid from the PHL. The recovery of acetic acid from the PHL by TIOA was increased from 10.34% to 66.60% with the dilution of TIOA to 20% by decanol at the HAc to TIOA molar ratio of 1, consequently, the equilibrium distribution coefficient KD increased. The effects of time, temperature and pH on the extraction process were also studied. The extraction process was very fast. The acetic acid extraction decreased from 65.13% to 57.34% with the rise of temperature to 50°C from 20°C. A higher pH increased the dissociation of acetic acid, as a result, decreased acetic acid extraction. The hemicelluloses in the PHL were unaffected on the extraction process of acetic acid. PMID:23619137

  8. Food Additives Permitted for Direct Addition to Food for Human Consumption; Folic Acid. Final rule.

    PubMed

    2016-04-15

    The Food and Drug Administration (FDA or we) is amending the food additive regulations to provide for the safe use of folic acid in corn masa flour. We are taking this action in response to a food additive petition filed jointly by Gruma Corporation, Spina Bifida Association, March of Dimes Foundation, American Academy of Pediatrics, Royal DSM N.V., and National Council of La Raza. PMID:27101640

  9. Myo-inositol esters of indole-3-acetic acid are endogenous components of Zea mays L. shoot tissue

    NASA Technical Reports Server (NTRS)

    Chisnell, J. R.

    1984-01-01

    Indole-3-acetyl-myo-inositol esters have been demonstrated to be endogenous components of etiolated Zea mays shoots tissue. This was accomplished by comparison of the putative compounds with authentic, synthetic esters. The properties compared were liquid and gas-liquid chromatographic retention times and the 70-ev mass spectral fragmentation pattern of the pentaacetyl derivative. The amount of indole-3-acetyl-myo-inositol esters in the shoots was determined to be 74 nanomoles per kilogram fresh weight as measured by isotope dilution, accounting for 19% of the ester indole-3-acetic acid of the shoot. This work is the first characterization of an ester conjugate of indole-3-acetate acid from vegetative shoot tissue using multiple chromatographic properties and mass spectral identification. The kernel and the seedling shoot both contain indole-3-acetyl-myo-inositol esters, and these esters comprise approximately the same percentage of the total ester content of the kernel and of the shoot.

  10. Synthesis of new chalcone derivatives containing a rhodanine-3-acetic acid moiety with potential anti-bacterial activity.

    PubMed

    Chen, Zhen-Hua; Zheng, Chang-Ji; Sun, Liang-Peng; Piao, Hu-Ri

    2010-12-01

    With an intention to synergize the anti-bacterial activity of chalcones and rhodanine-3-acetic acid, several hybrid compounds possessing chalcone and rhodanine-3-acetic acid moieties were synthesized and tested for their anti-bacterial activity. Some compounds presented great anti-microbial activities against Gram-positive bacteria (including the multidrug-resistant clinical isolates). This class of compounds presented high potency against Staphylococcus aureus, among which the derivatives 5k with a MIC of 2 μg/mL was as active as the standard drug (norfloxacin) and less active than oxacillin. Compounds 5a-s did not inhibit the growth of Gram-negative bacteria Escherichia coli CCARM 1924 or E. coli CCARM 1356 at 64 μg/mL. PMID:20889240

  11. Simultaneous utilization of cellobiose, xylose, and acetic acid from lignocellulosic biomass for biofuel production by an engineered yeast platform.

    PubMed

    Wei, Na; Oh, Eun Joong; Million, Gyver; Cate, Jamie H D; Jin, Yong-Su

    2015-06-19

    The inability of fermenting microorganisms to use mixed carbon components derived from lignocellulosic biomass is a major technical barrier that hinders the development of economically viable cellulosic biofuel production. In this study, we integrated the fermentation pathways of both hexose and pentose sugars and an acetic acid reduction pathway into one Saccharomyces cerevisiae strain for the first time using synthetic biology and metabolic engineering approaches. The engineered strain coutilized cellobiose, xylose, and acetic acid to produce ethanol with a substantially higher yield and productivity than the control strains, and the results showed the unique synergistic effects of pathway coexpression. The mixed substrate coutilization strategy is important for making complete and efficient use of cellulosic carbon and will contribute to the development of consolidated bioprocessing for cellulosic biofuel. The study also presents an innovative metabolic engineering approach whereby multiple substrate consumption pathways can be integrated in a synergistic way for enhanced bioconversion. PMID:25587748

  12. Born Oppenheimer Molecular Dynamics calculation of the νO-H IR spectra for acetic acid cyclic dimers

    NASA Astrophysics Data System (ADS)

    El Amine Benmalti, Mohamed; Krallafa, Abdelghani; Gaigeot, Marie-Pierre

    2015-01-01

    Both ab initio molecular dynamics simulations based on the Born-Oppenheimer approach calculations and a quantum theoretical model are used in order to study the IR spectrum of the acetic acid dimer in the gas phase. The theoretical model is taking into account the strong anharmonic coupling, Davydov coupling, multiple Fermi resonances between the first harmonics of some bending modes and the first excited state of the symmetric combination of the two vO-H modes and the quantum direct and indirect relaxation. The IR spectra obtained from DFT-based molecular dynamics is compared with our theoretical lineshape and with experiment. Note that in a previous work we have shown that our approach reproduces satisfactorily the main futures of the IR experimental lineshapes of the acetic acid dimer [Mohamed el Amine Benmalti, Paul Blaise, H. T. Flakus, Olivier Henri-Rousseau, Chem Phys, 320(2006) 267-274.].

  13. Decontamination of aquatic vegetable leaves by removing trace toxic metals during pickling process with acetic acid solution.

    PubMed

    Wu, Wenbiao; Yang, Yixing

    2011-01-01

    The heavy-metal content of aquatic plants is mainly dependent upon their ecological system. This study indicated that although the toxic heavy-metal contents could be above the recommended maximum levels depending upon their concentrations in growing water, they can be decontaminated by pickling with 5% acetic acid solution. Almost all Cd, Hg, Ba, or Sb and 99.5% Pb, 96.7% Ag, or 97.1% Al were removed from Water Spinach leaves by soaking in acetic acid solution. For Water-Shield leaves, almost all Cd, Hg, Pb, Ba, or Sb and 95.0% Ag or 96.1% Al were removed. For Watercress leaves, almost all Cd, Hg, Ba, or Sb and 99.0% Pb or 99.7% Ag were removed. For Water Hyacinth leaves, almost all Cd, Ba, or Sb and 99.0% Hg, 98.5% Pb, 95.0% Ag, or 98.7% Al were removed. PMID:21888602

  14. Ecosystem-scale compensation points of formic and acetic acid in the central Amazon

    NASA Astrophysics Data System (ADS)

    Jardine, K.; Yañez Serrano, A.; Arneth, A.; Abrell, L.; Jardine, A.; Artaxo, P.; Alves, E.; Kesselmeier, J.; Taylor, T.; Saleska, S.; Huxman, T.

    2011-09-01

    Organic acids, central to terrestrial carbon metabolism and atmospheric photochemistry, are ubiquitous in the troposphere in the gas, particle, and aqueous phases. As the dominant organic acids in the atmosphere, formic acid (FA, HCOOH) and acetic acid (AA, CH3COOH) control precipitation acidity in remote regions and may represent a critical link between the terrestrial carbon and water cycles by acting as key intermediates in plant carbon and energy metabolism and aerosol-cloud-precipitation interactions. However, our understanding of the exchange of these acids between terrestrial ecosystems and the atmosphere is limited by a lack of field observations, the existence of biogenic and anthropogenic primary and secondary sources whose relative importance is unclear, and the fact that vegetation can act as both a source and a sink. Here, we first present data obtained from the tropical rainforest mesocosm at Biosphere 2 which isolates primary vegetation sources. Strong light and temperature dependent emissions enriched in FA relative to AA were simultaneously observed from individual branches (FA/AA = 2.1 ± 0.6) and mesocosm ambient air (FA/AA = 1.4 ± 0.3). We also present long-term observations of vertical concentration gradients of FA and AA within and above a primary rainforest canopy in the central Amazon during the 2010 dry and 2011 wet seasons. We observed a seasonal switch from net ecosystem-scale deposition during the dry season to net emissions during the wet season. This switch was associated with reduced ambient concentrations in the wet season (FA < 1.3 nmol mol-1, AA < 2.0 nmol mol-1) relative to the dry season (FA up to 3.3 nmol mol-1, AA up to 6.0 nmol mol-1), and a simultaneous increase in the FA/AA ambient concentration ratios from 0.3-0.8 in the dry season to 1.0-2.1 in the wet season. These observations are consistent with a switch between a biomass burning dominated source in the dry season (FA/AA < 1.0) to a vegetation dominated source in the

  15. Ecosystem-Scale Compensation Point Analysis of Formic and Acetic Acid in the Central Amazon

    NASA Astrophysics Data System (ADS)

    Yanez-Serrano, A. M.; Jardine, K. J.; Arneth, A.; Abrell, L.; Jardine, A. B.; Artaxo, P.; Gomes, E.; Kesselmeier, J.; Saleska, S. R.; Huxman, T. E.

    2011-12-01

    Organic acids, central to terrestrial carbon metabolism and atmospheric photochemistry, are ubiquitous in the troposphere in the gas, particle, and aqueous phases. As the dominant organic acids in the atmosphere, formic acid (FA, HCOOH) and acetic acid (AA, CH3COOH) control precipitation acidity in remote regions and may represent a critical link between the terrestrial carbon and water cycles by acting as key intermediates in plant carbon and energy metabolism and aerosol-cloud-precipitation interactions. However, our understanding of the exchange of these acids between terrestrial ecosystems and the atmosphere is limited by a lack of field observations, the existence of biogenic and anthropogenic primary and secondary sources whose relative importance is unclear, and the fact that vegetation can act as both a source and a sink. Here, we present results from the tropical rainforest mescosom at Biosphere 2 which isolates primary vegetation sources. Strong light and temperature dependent emissions of FA and AA were simultaneously observed from individual branches and mesocosm ambient air with a strong enrichment in FA (FA/AA = 1.4 +/- 0.3, R2 of 0.89 +/- 0.10). We also present long-term observations of vertical concentration gradients of FA and AA within and above a primary rainforest canopy in central Amazonia during the 2010 dry and 2011 wet seasons. We observed a seasonal switch from net ecosystem-scale deposition during the dry season to net emissions during the wet season. This switch was associated with reduced ambient concentrations in the wet season (FA < 1.3 ppbv, AA < 2.0 ppbv) relative to the dry season (FA up to 3.3 ppbv, AA up to 6.0 ppbv), and a simultaneous increase in the FA/AA ambient concentration ratios from 0.3-0.8 in the dry season to 1.0-2.1 in the wet season. These observations are consistent with a switch between a biomass burning dominated source in the dry season (FA/AA < 1.0) to a vegetation dominated source in the wet season and call into

  16. Ecosystem-scale compensation points of formic and acetic acid in the central Amazon

    NASA Astrophysics Data System (ADS)

    Jardine, K.; Yañez Serrano, A.; Arneth, A.; Abrell, L.; Jardine, A.; Artaxo, P.; Alves, E.; Kesselmeier, J.; Taylor, T.; Saleska, S.; Huxman, T.

    2011-12-01

    Organic acids, central to terrestrial carbon metabolism and atmospheric photochemistry, are ubiquitous in the troposphere in the gas, particle, and aqueous phases. As the dominant organic acids in the atmosphere, formic acid (FA, HCOOH) and acetic acid (AA, CH3COOH) control precipitation acidity in remote regions and may represent a critical link between the terrestrial carbon and water cycles by acting as key intermediates in plant carbon and energy metabolism and aerosol-cloud-precipitation interactions. However, our understanding of the exchange of these acids between terrestrial ecosystems and the atmosphere is limited by a lack of field observations, the existence of biogenic and anthropogenic primary and secondary sources whose relative importance is unclear, and the fact that vegetation can act as both a source and a sink. Here, we first present data obtained from the tropical rainforest mesocosm at Biosphere 2 which isolates primary vegetation sources. Strong light and temperature dependent emissions enriched in FA relative to AA were simultaneously observed from individual branches (FA/AA = 3.0 ± 0.7) and mesocosm ambient air (FA/AA = 1.4 ± 0.3). We also present long-term observations of vertical concentration gradients of FA and AA within and above a primary rainforest canopy in the central Amazon during the 2010 dry and 2011 wet seasons. We observed a seasonal switch from net ecosystem-scale deposition during the dry season to net emissions during the wet season. This switch was associated with reduced ambient concentrations in the wet season (FA < 1.3 nmol mol-1, AA < 2.0 nmol mol-1) relative to the dry season (FA up to 3.3 nmol mol-1, AA up to 6.0 nmol mol-1), and a simultaneous increase in the FA/AA ambient concentration ratios from 0.3-0.8 in the dry season to 1.0-2.1 in the wet season. These observations are consistent with a switch between a biomass burning dominated source in the dry season (FA/AA < 1.0) to a vegetation dominated source in the

  17. Direct determination of peracetic acid, hydrogen peroxide, and acetic acid in disinfectant solutions by far-ultraviolet absorption spectroscopy.

    PubMed

    Higashi, Noboru; Yokota, Hiroshi; Hiraki, Satoru; Ozaki, Yukihiro

    2005-04-01

    In this paper we propose a rapid and highly selective far-ultraviolet (FUV) spectroscopic method for the simultaneous determination of peracetic acid (PAA), hydrogen peroxide, and acetic acid (AA). For this purpose we developed a novel FUV spectrometer that enables us to measure the spectra down to 180 nm. Direct determination of PAA, H(2)O(2), and AA, the three main species in disinfectant solutions, was carried out by using their absorption bands in the 180-220-nm region. The proposed method does not require any reagents or catalysts, a calibration standard, and a complicated procedure for the analysis. The only preparation procedure requested is a dilution of H(2)O(2) with pure water to a concentration range lower than 0.2 wt % in the sample solutions. Usually, the required concentration range can be obtained by the 10 times volume dilution of the actual disinfectant solutions. As the measured sample does not leave any impurity for the disinfection, it can be reused completely by using a circulation system. The detection limit for PAA of the new FUV spectrometer was evaluated to be 0.002 wt %, and the dynamic ranges of the measured concentrations were from 0 to 0.05 wt %, from 0 to 0.2 wt %, and from 0 to 0.2 wt % for PAA, H(2)O(2), and AA, respectively. The response time for the simultaneous determination of the three species is 30 s, and the analysis is applicable even to the flowing samples. This method may become a novel approach for the continuous monitoring of PAA in disinfectant solutions on the process of sterilization. PMID:15801764

  18. Design, synthesis and SAR studies of GABA uptake inhibitors derived from 2-substituted pyrrolidine-2-yl-acetic acids.

    PubMed

    Steffan, Tobias; Renukappa-Gutke, Thejavathi; Höfner, Georg; Wanner, Klaus T

    2015-03-15

    In this paper, we disclose the design and synthesis of a series of 2-substituted pyrrolidine-2-yl-acetic acid as core structures and the N-arylalkyl derivatives thereof as potential GABA transport inhibitors. The 2-position in the side chain of pyrrolidine-2-yl-acetic acid derivatives was substituted with alkyl, hydroxy and amino groups to modulate the activity and selectivity to mGAT1 and mGAT4 proteins. SAR studies of the compounds performed for the four mouse GABA transporter proteins (mGAT1-mGAT4) implied significant potencies and subtype selectivities for 2-hydroxy-2-pyrrolidine-2-yl-acetic acid derivatives. The racemate rac-(u)-13c exhibited the highest potency (pIC50 5.67) at and selectivity for mGAT1 in GABA uptake assays. In fact, the potency of rac-(u)-13c at hGAT-1 (pIC50 6.14) was even higher than its potency at mGAT1. These uptake results for rac-(u)-13c are in line with the binding affinities to the aforesaid proteins mGAT1 (pKi 6.99) and hGAT-1 (pKi 7.18) determined by MS Binding Assay based on NO711 as marker quantified by LC-ESI-MS-MS analysis. Interestingly, the 2-hydroxy-2-pyrrolidine-2-yl-acetic acid rac-(u)-13d containing 2-{[tris(4-methoxyphenyl)]methoxy} ethyl group at the nitrogen atom of the pyrrolidine ring showed high potency at mGAT4 and a comparatively better selectivity for this protein (>15 against mGAT3) than the well known mGAT4 uptake inhibitor (S)-SNAP-5114. PMID:25698617

  19. Competitive fragmentation pathways of acetic acid dimer explored by synchrotron VUV photoionization mass spectrometry and electronic structure calculations

    SciTech Connect

    Guan Jiwen; Hu Yongjun; Zou Hao; Cao Lanlan; Liu Fuyi; Shan Xiaobin; Sheng Liusi

    2012-09-28

    In present study, photoionization and dissociation of acetic acid dimers have been studied with the synchrotron vacuum ultraviolet photoionization mass spectrometry and theoretical calculations. Besides the intense signal corresponding to protonated cluster ions (CH{sub 3}COOH){sub n}{center_dot}H{sup +}, the feature related to the fragment ions (CH{sub 3}COOH)H{sup +}{center_dot}COO (105 amu) via {beta}-carbon-carbon bond cleavage is observed. By scanning photoionization efficiency spectra, appearance energies of the fragments (CH{sub 3}COOH){center_dot}H{sup +} and (CH{sub 3}COOH)H{sup +}{center_dot}COO are obtained. With the aid of theoretical calculations, seven fragmentation channels of acetic acid dimer cations were discussed, where five cation isomers of acetic acid dimer are involved. While four of them are found to generate the protonated species, only one of them can dissociate into a C-C bond cleavage product (CH{sub 3}COOH)H{sup +}{center_dot}COO. After surmounting the methyl hydrogen-transfer barrier 10.84 {+-} 0.05 eV, the opening of dissociative channel to produce ions (CH{sub 3}COOH){sup +} becomes the most competitive path. When photon energy increases to 12.4 eV, we also found dimer cations can be fragmented and generate new cations (CH{sub 3}COOH){center_dot}CH{sub 3}CO{sup +}. Kinetics, thermodynamics, and entropy factors for these competitive dissociation pathways are discussed. The present report provides a clear picture of the photoionization and dissociation processes of the acetic acid dimer in the range of the photon energy 9-15 eV.

  20. Simultaneous extraction and HPLC determination of 3-indole butyric acid and 3-indole acetic acid in pea plant by using ionic liquid-modified silica as sorbent.

    PubMed

    Sheikhian, Leila; Bina, Sedigheh

    2016-01-15

    In this study, ionic liquid-modified silica was used as sorbent for simultaneous extraction and preconcentration of 3-indole butyric acid and 3-indole acetic acid in pea plants. The effect of some parameters such as pH and ionic strength of sample solution, amount of sorbent, flow rate of aqueous sample solution and eluent solution, concentration of eluent solution, and temperature were studied for each hormone solution. Percent extraction of 3-indole butyric acid and 3-indole acetic acid was strongly affected by pH of aqueous sample solution. Ionic strength of aqueous phase and temperature showed no serious effects on extraction efficiency of studied plant hormones. Obtained breakthrough volume was 200mL for each of studied hormones. Preconcentration factor for spectroscopic and chromatographic determination of studied hormones was 100 and 4.0×10(3) respectively. Each solid sorbent phase was reusable for almost 10 times of extraction/stripping procedure. Relative standard deviations of extraction/stripping processes of 3-indole butyric acid and 3-indole acetic acid were 2.79% and 3.66% respectively. The calculated limit of detections for IBA and IAA were 9.1×10(-2)mgL(-1) and 1.6×10(-1)mgL(-1) respectively. PMID:26701202

  1. Photoinduced amino-imino tautomerization reaction in 2-aminopyrimidine and its methyl derivatives with acetic acid.

    PubMed

    Kitamura, Teruyoshi; Hikita, Atushi; Ishikawa, Hironori; Fujimoto, Akira

    2005-12-01

    The electronic absorption and fluorescence spectra of 2-aminopyrimidine (2APM), 2-amino-4-methylpyrimidine (2A4MPM), and 2-amino-4,6-dimethylpyrimidine (2ADMPM) with acetic acid (AcOH) were measured in isooctane (2,2,4-trimethylpentane) at room temperature. From the absorption spectra, a hydrogen-bonded complex formation of the 2APM/AcOH, 2A4MPM/AcOH, and 2ADMPM/AcOH systems was recognized in isooctane. The enthalpy changes (-DeltaH) for the complex formation were estimated to be ca. 41.2-45.1 kJ mol-1 and increased in proportion to the numbers of the methyl group introduced into the 2APM. The -DeltaH values refer to the formation of the hydrogen-bonded 1:1 complex between the ring nitrogen atom and NH2 group of the aminopyrimidine and the OH and CO groups of AcOH, respectively. In the 2A4MPM/AcOH double hydrogen-bonded complex the OH group of AcOH is thought to be linked to the ring nitrogen at the 1-postion of 2A4MPM. The fluorescence spectral results indicate that the double proton transfer reaction takes place during the excited state, and gives rise to an imino-tautomer vibration emission, from analogy with the fluorescences of 1-methyl-2(1H)-pyrimidinimine (MPMI), 1,4-dimethyl-2(1H)-pyrimidinimine (DMPMI), and 1,4,6-trimethyl-2(1H)-pyrimidinimine (TMPMI). The fluorescence quantum yields of the imino-tautomers also increased in proportion to the numbers of the methyl group introduced into the 2APM. PMID:15978861

  2. Photoinduced amino-imino tautomerization reaction in 2-aminopyrimidine and its methyl derivatives with acetic acid

    NASA Astrophysics Data System (ADS)

    Kitamura, Teruyoshi; Hikita, Atushi; Ishikawa, Hironori; Fujimoto, Akira

    2005-12-01

    The electronic absorption and fluorescence spectra of 2-aminopyrimidine (2APM), 2-amino-4-methylpyrimidine (2A4MPM), and 2-amino-4,6-dimethylpyrimidine (2ADMPM) with acetic acid (AcOH) were measured in isooctane (2,2,4-trimethylpentane) at room temperature. From the absorption spectra, a hydrogen-bonded complex formation of the 2APM/AcOH, 2A4MPM/AcOH, and 2ADMPM/AcOH systems was recognized in isooctane. The enthalpy changes (-Δ H) for the complex formation were estimated to be ca. 41.2-45.1 kJ mol -1 and increased in proportion to the numbers of the methyl group introduced into the 2APM. The -Δ H values refer to the formation of the hydrogen-bonded 1:1 complex between the ring nitrogen atom and NH 2 group of the aminopyrimidine and the OH and C dbnd O groups of AcOH, respectively. In the 2A4MPM/AcOH double hydrogen-bonded complex the OH group of AcOH is thought to be linked to the ring nitrogen at the 1-postion of 2A4MPM. The fluorescence spectral results indicate that the double proton transfer reaction takes place during the excited state, and gives rise to an imino-tautomer vibration emission, from analogy with the fluorescences of 1-methyl-2(1H)-pyrimidinimine (MPMI), 1,4-dimethyl-2(1H)-pyrimidinimine (DMPMI), and 1,4,6-trimethyl-2(1H)-pyrimidinimine (TMPMI). The fluorescence quantum yields of the imino-tautomers also increased in proportion to the numbers of the methyl group introduced into the 2APM.

  3. Divergent effects of flavone acetic acid on established versus developing tumour blood flow.

    PubMed Central

    Mahadevan, V.; Hart, I. R.

    1991-01-01

    Flavone Acetic Acid (FAA) exerts much of its effect by reducing tumour blood flow. Previous studies on FAA-induced changes in blood flow have used established tumours with a functional microvasculature. Using radioactive Xenon(133Xe) clearance to monitor local blood flow we show that the effects of FAA are dependent on the presence of this functional microvasculature with no evidence that FAA inhibits the actual development of tumour microcirculation. Thus, administration of multiple doses of FAA around the time of tumour cell injection failed to diminish t1/2 values of 133Xe (e.g. t1/2 16 min for FAA vs 14 min for saline controls at 10 days) or to affect tumour volumes (5.55 +/- 0.06 cm3 in FAA-treated animals vs 5.7 +/- 1.3 cm3 in controls at 25 days). In marked contrast a single dose of FAA (200 mg kg-1 body weight) 2 weeks after tumour cell injection dramatically extended t1/2 times (47 min for FAA vs 7 min for controls; P less than 0.001) and significantly reduced tumour burden. This effect is specific for tumour microvasculature and is not directed simply at new vessels since a similar treatment of animals with implanted-sponge-induced granulation tissue had no effect on t1/2 times (6.8 +/- 1.1 min for FAA at 200 mg kg-1 vs 7.2 +/- 1.0 min for saline-treated controls. PMID:1712621

  4. Healing Effect of Pistacia Atlantica Fruit Oil Extract in Acetic Acid-Induced Colitis in Rats

    PubMed Central

    Tanideh, Nader; Masoumi, Samira; Hosseinzadeh, Massood; Safarpour, Ali Reza; Erjaee, Hoda; Koohi-Hosseinabadi, Omid; Rahimikazerooni, Salar

    2014-01-01

    Background: Considering the anti-oxidant properties of Pistacia atlantica and lack of data regarding its efficacy in the treatment of ulcerative colitis, this study aims at investigating the effect of the Pistacia atlantica fruit extract in treating experimentally induced colitis in a rat model. Methods: Seventy male Sprague-Dawley rats (weighing 220±20 g) were used. All rats fasted 24 hours before the experimental procedure. The rats were randomly divided into 7 groups, each containing 10 induced colitis with 2ml acetic acid (3%). Group 1 (Asacol), group 2 (base gel) and group 7 (without treatment) were assigned as control groups. Group 3 (300 mg/ml) and group 4 (600 mg/ml) received Pistacia atlantica fruit orally. Group 5 (10% gel) and group 6 (20% gel) received Pistacia atlantica in the form of gel as enema. Macroscopic, histopathological examination and MDA measurement were carried out. Results: All groups revealed significant macroscopic healing in comparison with group 7 (P<0.001). Regarding microscopic findings in the treatment groups compared with group 7, the latter group differed significantly with groups 1, 2, 4 and 6 (P<0.001). There was a significant statistical difference in MDA scores of the seven treatment groups (F(5,54)=76.61, P<0.001). Post-hoc comparisons indicated that the mean±SD score of Asacol treated group (1.57±0.045) was not significantly different from groups 4 (1.62±0.024) and 6 (1.58±0.028). Conclusion: Our study showed that a high dose of Pistacia atlantica fruit oil extract, administered orally and rectally can improve colitis physiologically and pathologically in a rat model, and may be efficient for ulcerative colitis. PMID:25429174

  5. Dietary supplementation with tributyrin alleviates intestinal injury in piglets challenged with intrarectal administration of acetic acid.

    PubMed

    Hou, Yongqing; Wang, Lei; Yi, Dan; Ding, Binying; Chen, Xing; Wang, Qingjing; Zhu, Huiling; Liu, Yulan; Yin, Yulong; Gong, Joshua; Wu, Guoyao

    2014-05-28

    Tributyrin (TBU) is a good dietary source of butyrate and has beneficial effects on the maintenance of normal intestinal morphology. The present study tested the hypothesis that dietary TBU supplementation could alleviate intestinal injury in the acetic acid (ACA)-induced porcine model of colitis. A total of eighteen piglets (25 d old) were randomly allocated to one of three treatment groups (control, ACA and TBU). The control and ACA groups were fed a basal diet and the TBU group was fed the basal diet supplemented with 0·1 % TBU. On day 15 of the trial, under anaesthesia, a soft catheter was inserted into the rectum of piglets (20-25 cm from the anus), followed by administration of either saline (control group) or ACA (10 ml of 10 % ACA solution for ACA and TBU groups). On day 22 of the trial, after venous blood samples were collected, piglets were killed to obtain mid-ileum and mid-colon mucosae. Compared with the control group, the ACA group exhibited an increase (P< 0·05) in lymphocyte counts, creatinine, PGE2, and malondialdehyde concentrations and diamine oxidase and inducible NO synthase activities in the plasma and lymphocyte density in the colon and a decrease in insulin concentrations and glutathione peroxidase activity, ileal villus height:crypt depth ratios and goblet cell numbers in the colon. These adverse effects of ACA were attenuated by TBU supplementation. Moreover, TBU prevented the ACA-induced increase in caspase-3 levels while enhancing claudin-1 protein and epidermal growth factor receptor (EGFR) mRNA expression in the colonic mucosa. Collectively, these results indicate that dietary supplementation with 0·1 % TBU alleviates ACA-induced intestinal injury possibly by inhibiting apoptosis, promoting tight-junction formation and activating EGFR signalling. PMID:24506942

  6. Healing Acceleration of Acetic Acid-induced Colitis by Marigold (Calendula officinalis) in Male Rats

    PubMed Central

    Tanideh, Nader; Jamshidzadeh, Akram; Sepehrimanesh, Masood; Hosseinzadeh, Masood; Koohi-Hosseinabadi, Omid; Najibi, Asma; Raam, Mozhdeh; Daneshi, Sajad; Asadi-Yousefabad, Seyedeh-Leili

    2016-01-01

    Background/Aim: Ulcerative colitis (UC) is a type of chronic inflammatory bowel disease with unknown etiology. Several therapeutic strategies such as consumption of medicinal plants have been used for its treatment. The aim of this study was to evaluate healing effects of Calendula officinalis hydroalcoholic extract in experimentally induced UC in rat. Materials and Methods: Ninety-six rats, weighing 200 ± 20 g, were randomly divided into eight equal groups. UC induced by 3% acetic acid and oral doses of C. officinalis extract, 1500 and 3000 mg/kg, and enema (gel 10% and 20%) were given. Two groups as positive controls were given asacol (enema) and oral mesalamine. Negative control groups were given normal saline and base gel. On days 3 and 7, intestinal histopathology and weight changes, plus oxidative stress indices including malondialdehyde (MDA) level and myeloperoxidase (MPO) activity were assayed. Results: A significant increase in the body weight of rats was seen in the group given C. officinalis extract 3000 mg/kg orally, oral mesalamine, and 20% intracolonic gel form of marigold extract compared with negative control and base gel groups during the experimental period. Acute inflammation and granular atrophy after UC induction were resolved completely completely by both 20% intracolonic gel and 3000 mg/kg orally. An increase in MPO activity and a decrease in MDA level in response to oral and intracolonic gel form of C. officinalis were observed 3 and and 7 days after treatment (P < 0.05). Conclusion: Our results indicate that oral and enema forms of hydroalcoholic extract of C. officinalis can be offered as are potential therapeutic agents for UC induced in rats. PMID:26831607

  7. Adipic gets the acid test as flue gas scrubber additive

    SciTech Connect

    Miller, I.R.

    1980-02-11

    The first full-scale demonstration of adipic acid for such use, to be conducted early in the summer of 1980 in a 200 MW power plant burning high-sulfur coal, is designed to clarify the costs and show how to reduce losses of adipic acid via degradation. Adipic acid improves SO/sub 2/ removal by acting as a buffer to limit the pH drop normally occurring at the gas-liquid interface so that the higher SO/sub 2/ concentration in the surface film improves liquid-phase mass transfer; it also promotes higher limestone utilization. Prepared by the Tennessee Valley Authority, a preliminary economic analysis for a 500 MW plant burning 4% sulfur coal indicates that the addition of 1500 ppM of adipic acid (limestone at $7/ton and the acid at $840/ton) would raise SO/sub 2/ removal from 90 to 95%, reduce the total capital investment from $41.5 to $39.5 million, and have a first year revenue requirement of $19.9 million vs. $20.9 million without the acid. The large-scale trial will also help clarify concern over unpleasant odors that have been reported at test sites of the limestone/adipic system; valeric acid has been identified as the cause.

  8. Acetic acid as an adjunct vital stain in diagnosis of tobacco-associated oral lesions: A pilot study

    PubMed Central

    Vinuth, DP; Agarwal, Poonam; Kale, Alka D; Hallikeramath, Seema; Shukla, Deepika

    2015-01-01

    Background: One of the most important risk factors for oral precancer and cancer in India is the use of tobacco. In chronic tobacco users, the mucosa may appear clinically healthy, however, changes are observed histologically. Screening of such tobacco users for an early diagnosis is, therefore, of paramount importance. Several adjunctive diagnostic modalities have been used in the past, but none has been conclusively validated as confirmative and cost-effective screening methodology. The aim of this study was to evaluate the use of 5% acetic acid as a vital staining agent in tobacco-associated oral lesions. Materials and Methods: The study subjects were divided into two groups. Group I (n = 40) subjects with a history of chronic tobacco use and clinically apparent normal mucosa. Group II (n = 40) subjects suspected of having oral cancer, 5% acetic acid was applied to the mucosa/lesions, followed by incisional biopsy for confirmatory diagnosis. Results: The sensitivity and specificity for Groups I and II were 97%, 50% and 95%, 60%, respectively. Positive predictive value (PPV) and negative predictive value (NPV) of Group I were 0.95 and 0.66. Group II showed PPV and NPV of 0.95 and 0.60. Conclusion: The results of this study suggest that acetic acid holds promise for future. Hence, further studies are needed to be undertaken on a large scale to assess its potential as a screening tool for high-risk individuals and oral cancer. PMID:26604486

  9. Ab initio Hartree-Fock investigation of 1- H-pyrrolo[3,2- b]pyridine-3-yl acetic acid

    NASA Astrophysics Data System (ADS)

    Ramek, Michael; Tomić, Sanja

    2001-09-01

    The potential energy surface of 1- H-pyrrolo[3,2- b]pyridine-3-yl acetic acid has been investigated via RIIF/6-31G* calculations. The stationary points and reaction paths for syn orientation of the COOH group were determined and are compared with those of the derivatives of 3-indole acetic acid, which act as plant growth hormones. 1- H-pyrrolo[3,2- b]pyridine-3-yl acetic acid forms a kinetically stable conformer with a strong intramolecular hydrogen bond, in which the COOH group is in anti orientation. The influence of this hydrogen bond on bond lengths and vibration frequencies is described.

  10. Arachidonate metabolism, 5-hydroxytryptamine release and aggregation in human platelets activated by palmitaldehyde acetal phosphatidic acid.

    PubMed Central

    Brammer, J. P.; Maguire, M. H.

    1984-01-01

    Palmitaldehyde acetal phosphatidic acid ( PGAP ) caused dose-dependent aggregation of human platelets resuspended in modified Tyrode medium, with a threshold concentration of 0.5-1 microM and an EC50 of 4 microM. Concentrations of PGAP which elicited biphasic irreversible aggregation concomitantly induced formation of 1.02 +/- 0.029 nmol (mean +/- s.e. mean) of malondialdehyde (MDA) per 10(9) platelets and caused release of 58 +/- 2.8% of platelet [14C]-5-hydroxytryptamine ([14C]-5-HT) from prelabelled platelets; no MDA formation or [14C]-5-HT release occurred at lower doses of PGAP which elicited only monophasic reversible aggregation. Adenosine 5'-pyrophosphate (ADP)-induced platelet activation resulted in formation of 0.344 +/- 0.004 nmol of MDA per 10(9) platelets in association with irreversible aggregation and 49.1 +/- 1% release of [14C]-5-HT. Mepacrine, a phospholipase A2 inhibitor, at 2.5 microM reduced PGAP -induced MDA formation and [14C]-5-HT release by the resuspended platelets without affecting irreversible aggregation; higher concentrations of mepacrine abolished all three responses. Chlorpromazine, a calmodulin antagonist, similarly inhibited PGAP -induced MDA formation and irreversible aggregation, and at 100 microM abolished monophasic aggregation. The cyclo-oxygenase inhibitor indomethacin caused a concentration-dependent reduction of PGAP -induced MDA formation by resuspended human platelets without significantly inhibiting [14C]-5-HT release or irreversible aggregation; concentrations (greater than or equal to 1.75 microM) which inhibited MDA formation by more than 94% abolished [14C]-5-HT release, and converted second phase irreversible aggregation to an extensive reversible response. 2-Methylthioadenosine 5'-phosphate (2 methylthio-AMP), an ADP antagonist, inhibited PGAP -induced MDA formation, [14C]-5-HT release and second phase aggregation in the human platelet suspensions in a parallel, concentration-dependent manner; at 9.4 microM 2

  11. Improvement of the antifungal activity of lactic acid bacteria by addition to the growth medium of phenylpyruvic acid, a precursor of phenyllactic acid.

    PubMed

    Valerio, Francesca; Di Biase, Mariaelena; Lattanzio, Veronica M T; Lavermicocca, Paola

    2016-04-01

    The aim of the current study was to improve the antifungal activity of eight lactic acid bacterial (LAB) strains by the addition of phenylpyruvic acid (PPA), a precursor of the antifungal compound phenyllactic acid (PLA), to a defined growth medium (DM). The effect of PPA addition on the LABs antifungal activity related to the production of organic acids (PLA, d-lactic, l-lactic, acetic, citric, formic and 4-hydroxy-phenyllactic acids) and of other phenylpyruvic-derived molecules, was investigated. In the presence of PPA the inhibitory activity (expressed as growth inhibition percentage) against fungal bread contaminants Aspergillus niger and Penicillium roqueforti significantly increased and was, even if not completely, associated to PLA increase (from a mean value of 0.44 to 0.93 mM). While the inhibitory activity against Endomyces fibuliger was mainly correlated to the low pH and to lactic, acetic and p-OH-PLA acids. When the PCA analysis based on data of growth inhibition percentage and organic acid concentrations was performed, strains grown in DM+PPA separated from those grown in DM and the most active strains Lactobacillus plantarum 21B, Lactobacillus fermentum 18B and Lactobacillus brevis 18F grouped together. The antifungal activity resulted to be strain-related, based on a different mechanism of action for filamentous fungi and the yeast and was not exclusively associated to the increase of PLA. Therefore, a further investigation on the unique unidentified peak in HPLC-UV chromatograms, was performed by LC-MS/MS analysis. Actually, full scan mass spectra (negative ion mode) recorded at the retention time of the unknown compound, showed a main peak of m/z 291.0 which was consistent with the nominal mass of the molecular ion [M-H](-) of polyporic acid, a PPA derivative whose antifungal activity has been previously reported (Brewer et al., 1977). In conclusion, the addition of PPA to the growth medium contributed to improve the antifungal activity of LAB

  12. Identifying (E)-4,8-dimethyl-1,3,7-nonatriene plus acetic acid as a new lure for male and female codling moth (Lepidoptera: Tortricidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Laboratory and field studies were conducted to measure the responses of adult codling moth, Cydia pomonella (L.), to several plant volatiles presented alone and in combination with acetic acid. Plant volatiles included ethyl (E,Z)-2,4-decadienoate (pear ester), (E)-ß-farnesene, (Z)-3-hexenyl acetate...

  13. 40 CFR 721.2076 - D-Glucuronic acid, polymer with 6-deoxy-L-mannose and D-glucose, acetate, calcium magnesium...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-deoxy-L-mannose and D-glucose, acetate, calcium magnesium potassium sodium salt. 721.2076 Section 721...-Glucuronic acid, polymer with 6-deoxy-L-mannose and D-glucose, acetate, calcium magnesium potassium sodium... potassium sodium salt (PMN P-00-7; CAS No.125005-87-0) is subject to reporting under this section for...

  14. 40 CFR 721.2076 - D-Glucuronic acid, polymer with 6-deoxy-L-mannose and D-glucose, acetate, calcium magnesium...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-deoxy-L-mannose and D-glucose, acetate, calcium magnesium potassium sodium salt. 721.2076 Section 721...-Glucuronic acid, polymer with 6-deoxy-L-mannose and D-glucose, acetate, calcium magnesium potassium sodium... potassium sodium salt (PMN P-00-7; CAS No.125005-87-0) is subject to reporting under this section for...

  15. 40 CFR 721.2076 - D-Glucuronic acid, polymer with 6-deoxy-L-mannose and D-glucose, acetate, calcium magnesium...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-deoxy-L-mannose and D-glucose, acetate, calcium magnesium potassium sodium salt. 721.2076 Section 721...-Glucuronic acid, polymer with 6-deoxy-L-mannose and D-glucose, acetate, calcium magnesium potassium sodium... potassium sodium salt (PMN P-00-7; CAS No.125005-87-0) is subject to reporting under this section for...

  16. Thallium acetate

    Integrated Risk Information System (IRIS)

    Jump to main content . Integrated Risk Information System Recent Additions | Contact Us Search : All EPA IRIS • You are here : EPA Home • Research • Environmental Assessment • IRIS • IRIS Summaries Redirect Page As of September 30 , 2009 , the assessment summary for Thallium acetate is included in t

  17. The Cytosolic pH of Individual Saccharomyces cerevisiae Cells Is a Key Factor in Acetic Acid Tolerance

    PubMed Central

    Fernández-Niño, Miguel; Marquina, Maribel; Swinnen, Steve; Rodríguez-Porrata, Boris

    2015-01-01

    It was shown recently that individual cells of an isogenic Saccharomyces cerevisiae population show variability in acetic acid tolerance, and this variability affects the quantitative manifestation of the trait at the population level. In the current study, we investigated whether cell-to-cell variability in acetic acid tolerance could be explained by the observed differences in the cytosolic pHs of individual cells immediately before exposure to the acid. Results obtained with cells of the strain CEN.PK113-7D in synthetic medium containing 96 mM acetic acid (pH 4.5) showed a direct correlation between the initial cytosolic pH and the cytosolic pH drop after exposure to the acid. Moreover, only cells with a low initial cytosolic pH, which experienced a less severe drop in cytosolic pH, were able to proliferate. A similar correlation between initial cytosolic pH and cytosolic pH drop was also observed in the more acid-tolerant strain MUCL 11987-9. Interestingly, a fraction of cells in the MUCL 11987-9 population showed initial cytosolic pH values below the minimal cytosolic pH detected in cells of the strain CEN.PK113-7D; consequently, these cells experienced less severe drops in cytosolic pH. Although this might explain in part the difference between the two strains with regard to the number of cells that resumed proliferation, it was observed that all cells from strain MUCL 11987-9 were able to proliferate, independently of their initial cytosolic pH. Therefore, other factors must also be involved in the greater ability of MUCL 11987-9 cells to endure strong drops in cytosolic pH. PMID:26341199

  18. Structure and gene cluster of the O-antigen of Escherichia coli O156 containing a pyruvic acid acetal.

    PubMed

    Duan, Zhifeng; Senchenkova, Sof'ya N; Guo, Xi; Perepelov, Andrei V; Shashkov, Alexander S; Liu, Bin; Knirel, Yuriy A

    2016-07-22

    The lipopolysaccharide of Escherichia coli O156 was degraded under mild acidic and alkaline conditions and the resulting polysaccharides were studied by sugar analysis and (1)H and (13)C NMR spectroscopy. The following structure of the pentasaccharide repeating unit of the O-polysaccharide was established: where Rpyr indicates R-configurated pyruvic acid acetal. Minor O-acetyl groups also were present and tentatively localized on the Gal residues. The gene cluster for biosynthesis of the O-antigen of E. coli O156 was analyzed and shown to be consistent with the O-polysaccharide structure. PMID:27177202

  19. Biogas Production on Demand Regulated by Butyric Acid Addition

    NASA Astrophysics Data System (ADS)

    Kasper, K.; Schiffels, J.; Krafft, S.; Kuperjans, I.; Elbers, G.; Selmer, T.

    2016-03-01

    Investigating effects of volatile fatty acids on the biogas process it was observed that butyric acid can be used for transient stimulation of the methane production in biogas plants operating with low energy substrates like cattle manure. Upon addition of butyrate the methane output of the reactors doubled within 24 h and reached almost 3-times higher methane yields within 3-4 days. Butyrate was quantitatively eliminated and the reactors returned to the original productivity state within 3 days when application of butyrate was stopped. The opportunity to use butyrate feeding for increased biogas production on demand is discussed.

  20. Measuring acetic and formic acid by proton transfer reaction-mass spectrometry: sensitivity, humidity dependence, and quantifying interferences

    NASA Astrophysics Data System (ADS)

    Baasandorj, M.; Millet, D. B.; Hu, L.; Mitroo, D.; Williams, B. J.

    2014-10-01

    We present a detailed investigation of the factors governing the quantification of formic acid (FA), acetic acid (AA) and their relevant mass analogues by proton transfer reaction-mass spectrometry (PTR-MS), assess the underlying fragmentation pathways and humidity dependencies, and present a new method for separating FA and AA from their main isobaric interferences. PTR-MS sensitivities towards glycolaldehyde, ethyl acetate and peroxyacetic acid at m/z 61 are comparable to that for AA; when present, these species will interfere with ambient AA measurements by PTR-MS. Likewise, when it is present, dimethyl ether can interfere with FA measurements. On the other hand, for E/N = 125 Townsend (Td), the PTR-MS sensitivity towards ethanol at m/z 47 is 5-20× lower than for FA; ethanol will then only be an important interference when present in much higher abundance than FA. Sensitivity towards 2-propanol is <1% of that for AA, so that propanols will not in general represent a significant interference for AA. Hydrated product ions of AA, glycoaldehyde, and propanols occur at m/z 79, which is also commonly used to measure benzene. However, the resulting interference for benzene is only significant when E/N is low (<∼100 Td). Addition of water vapor affects the PTR-MS response to a given compound by (i) changing the yield for fragmentation reactions, and (ii) increasing the importance of ligand switching reactions. In the case of AA, sensitivity to the molecular ion increases with humidity at low E/N, but decreases with humidity at high E/N due to water-driven fragmentation. Sensitivity towards FA decreases with humidity throughout the full range of E/N. For glycoaldehyde and the alcohols, the sensitivity increases with humidity due to ligand switching reactions (at low E/N) and reduced fragmentation in the presence of water (at high E/N). Their role as interferences will typically be greatest at high humidity. For compounds such as AA where the humidity effect depends