Note: This page contains sample records for the topic acid benzoic acid from Science.gov.
While these samples are representative of the content of Science.gov,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of Science.gov
to obtain the most current and comprehensive results.
Last update: November 12, 2013.
1

21 CFR 184.1021 - Benzoic acid.  

Code of Federal Regulations, 2010 CFR

... 3 2010-01-01 2009-04-01 true Benzoic acid. 184.1021 Section 184.1021 Food and...Specific Substances Affirmed as GRAS § 184.1021 Benzoic acid. (a) Benzoic acid is the chemical benzenecarboxylic acid (C7...

2010-01-01

2

21 CFR 184.1021 - Benzoic acid.  

Code of Federal Regulations, 2010 CFR

... 3 2009-04-01 2009-04-01 false Benzoic acid. 184.1021 Section 184.1021 Food and...Specific Substances Affirmed as GRAS § 184.1021 Benzoic acid. (a) Benzoic acid is the chemical benzenecarboxylic acid (C7...

2009-04-01

3

21 CFR 184.1021 - Benzoic acid.  

Code of Federal Regulations, 2013 CFR

...nature in free and combined forms. Among the foods in which benzoic acid occurs naturally are cranberries, prunes, plums, cinnamon, ripe cloves, and most berries. Benzoic acid is manufactured by treating molten phthalic anhydride with steam in...

2013-04-01

4

Treatment of Cancer Using Benzoic Acid Derivatives.  

National Technical Information Service (NTIS)

The present invention provides a method of treating cancer using benzoic acid derivatives, alone or in combination with standard treatments such as chemotherapy and radiotherapy. Also provided are methods of screening for benzoic derivatives based on thei...

D. Morais D. Rodriquez L. Liebes P. C. Brooks

2005-01-01

5

40 CFR 721.1680 - Substituted benzoic acid (generic).  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Substituted benzoic acid (generic). 721.1680 Section...Substances § 721.1680 Substituted benzoic acid (generic). (a) Chemical...identified generically as substituted benzoic acid (PMN P-01-423) is...

2013-07-01

6

Capillary Electrophoresis of Substituted Benzoic Acids  

ERIC Educational Resources Information Center

|A series of substituted benzoic acids (SBAs) are prepared by students. The pKa shift, a result of the electron-withdrawing or electron-donating characteristics of the subsistent is examined in reference to the electrophoretic migration behavior of benzoic acid.|

Mills, Nancy S.; Spence, John D.; Bushey, Michelle M.

2005-01-01

7

Photodissociation dynamics of benzoic acid  

NASA Astrophysics Data System (ADS)

The photodissociation of benzoic acid at 193 and 248 nm was investigated using multimass ion imaging techniques. Three dissociation channels were observed at 193 nm: (1) C6H5COOH-->C6H5+COOH, (2) C6H5COOH-->C6H5CO+OH, and (3) C6H5COOH-->C6H6+CO2. Only channels, (2) and (3), were observed at 248 nm. Comparisons of the ion intensities and photofragment translational energy distributions with the potential energies obtained from ab initio calculations and the branching ratios obtained from the Rice-Ramsperger-Kassel-Marcus theory suggest that the dissociation occurs on many electronic states.

Dyakov, Yuri A.; Bagchi, Arnab; Lee, Yuan T.; Ni, Chi-Kung

2010-01-01

8

Photodissociation dynamics of benzoic acid  

SciTech Connect

The photodissociation of benzoic acid at 193 and 248 nm was investigated using multimass ion imaging techniques. Three dissociation channels were observed at 193 nm: (1) C{sub 6}H{sub 5}COOH{yields}C{sub 6}H{sub 5}+COOH, (2) C{sub 6}H{sub 5}COOH{yields}C{sub 6}H{sub 5}CO+OH, and (3) C{sub 6}H{sub 5}COOH{yields}C{sub 6}H{sub 6}+CO{sub 2}. Only channels, (2) and (3), were observed at 248 nm. Comparisons of the ion intensities and photofragment translational energy distributions with the potential energies obtained from ab initio calculations and the branching ratios obtained from the Rice-Ramsperger-Kassel-Marcus theory suggest that the dissociation occurs on many electronic states.

Dyakov, Yuri A.; Bagchi, Arnab; Lee, Yuan T.; Ni, Chi-Kung [Institute of Atomic and Molecular Sciences, Academia Sinica, P.O. Box 23-166, Taipei 10617, Taiwan (China)

2010-01-07

9

40 CFR 721.10098 - Disubstituted benzoic acid, alkali metal salt (generic).  

Code of Federal Regulations, 2010 CFR

... false Disubstituted benzoic acid, alkali metal salt (generic). 721...10098 Disubstituted benzoic acid, alkali metal salt (generic). ...generically as disubstituted benzoic acid, alkali metal salt (PMN...

2010-07-01

10

40 CFR 721.10098 - Disubstituted benzoic acid, alkali metal salt (generic).  

Code of Federal Regulations, 2010 CFR

... false Disubstituted benzoic acid, alkali metal salt (generic). 721...10098 Disubstituted benzoic acid, alkali metal salt (generic). ...generically as disubstituted benzoic acid, alkali metal salt (PMN...

2009-07-01

11

40 CFR 721.10109 - Hexanoic acid, 2-ethyl-, mixed triesters with benzoic acid and trimethylolpropane.  

Code of Federal Regulations, 2010 CFR

...2-ethyl-, mixed triesters with benzoic acid and trimethylolpropane. 721...2-ethyl-, mixed triesters with benzoic acid and trimethylolpropane. (a...2-ethyl-, mixed triesters with benzoic acid and trimethylolpropane...

2009-07-01

12

40 CFR 721.10109 - Hexanoic acid, 2-ethyl-, mixed triesters with benzoic acid and trimethylolpropane.  

Code of Federal Regulations, 2010 CFR

...2-ethyl-, mixed triesters with benzoic acid and trimethylolpropane. 721...2-ethyl-, mixed triesters with benzoic acid and trimethylolpropane. (a...2-ethyl-, mixed triesters with benzoic acid and trimethylolpropane...

2010-07-01

13

21 CFR 582.3021 - Benzoic acid.  

Code of Federal Regulations, 2013 CFR

21 Food and Drugs 6 2013-04-01 2013-04-01... 582.3021 Section 582.3021 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT...GENERALLY RECOGNIZED AS SAFE Chemical Preservatives § 582.3021 Benzoic acid....

2013-04-01

14

Uptake of benzoic acid and chloro-substituted benzoic acids by alcaligenes denitrificans BRI 3010 and BRI 6011  

Microsoft Academic Search

The mechanism of uptake of benzoic and 2,4-dichlorobenzoic acid (2,4-DCBA) by Alcaligenes denitrificans BRI 3010 and BRI 6011 and Pseudomonas sp. strain B13, three organisms capable of degrading isomers of chlorinated benzoic acids, was investigated. In all three organisms, uptake of benzoic acid was inducible. For benzoic acid uptake into BRI 3010, monophasic saturation kinetics with apparent K{sub m} and

C. B. Miguez; J. M. Ingram; R. A. MacLeod

1995-01-01

15

40 CFR 721.10110 - Hexanoic acid, 2-ethyl-, mixed diesters with benzoic acid and neopentlyl glycol.  

Code of Federal Regulations, 2010 CFR

...2-ethyl-, mixed diesters with benzoic acid and neopentlyl glycol. 721...2-ethyl-, mixed diesters with benzoic acid and neopentlyl glycol. (a...2-ethyl-, mixed diesters with benzoic acid and neopentlyl glycol...

2009-07-01

16

40 CFR 721.10110 - Hexanoic acid, 2-ethyl-, mixed diesters with benzoic acid and neopentlyl glycol.  

Code of Federal Regulations, 2010 CFR

...2-ethyl-, mixed diesters with benzoic acid and neopentlyl glycol. 721...2-ethyl-, mixed diesters with benzoic acid and neopentlyl glycol. (a...2-ethyl-, mixed diesters with benzoic acid and neopentlyl glycol...

2010-07-01

17

40 CFR 721.1705 - Benzoic acid, 3-amino-, diazotized, coupled with 6-amino-4-hydroxy-2-naphthalenesulfonic acid...  

Code of Federal Regulations, 2010 CFR

...2009-07-01 2009-07-01 false Benzoic acid, 3-amino-, diazotized, coupled...Chemical Substances § 721.1705 Benzoic acid, 3-amino-, diazotized, coupled...substance generically identified as benzoic acid, 3-amino-, diazotized,...

2009-07-01

18

40 CFR 721.10111 - Hexanoic acid, 2-ethyl-, mixed diesters with benzoic acid and diethylene glycol.  

Code of Federal Regulations, 2010 CFR

...2-ethyl-, mixed diesters with benzoic acid and diethylene glycol. 721...2-ethyl-, mixed diesters with benzoic acid and diethylene glycol. (a...2-ethyl-, mixed diesters with benzoic acid and diethylene glycol...

2009-07-01

19

40 CFR 721.1705 - Benzoic acid, 3-amino-, diazotized, coupled with 6-amino-4-hydroxy-2-naphthalenesulfonic acid...  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Benzoic acid, 3-amino-, diazotized, coupled...Chemical Substances § 721.1705 Benzoic acid, 3-amino-, diazotized, coupled...substance generically identified as benzoic acid, 3-amino-, diazotized,...

2010-07-01

20

40 CFR 721.10111 - Hexanoic acid, 2-ethyl-, mixed diesters with benzoic acid and diethylene glycol.  

Code of Federal Regulations, 2010 CFR

...2-ethyl-, mixed diesters with benzoic acid and diethylene glycol. 721...2-ethyl-, mixed diesters with benzoic acid and diethylene glycol. (a...2-ethyl-, mixed diesters with benzoic acid and diethylene glycol...

2010-07-01

21

40 CFR 721.10098 - Disubstituted benzoic acid, alkali metal salt (generic).  

Code of Federal Regulations, 2013 CFR

...Disubstituted benzoic acid, alkali metal salt (generic). 721.10098 Section 721...Disubstituted benzoic acid, alkali metal salt (generic). (a) Chemical substance...disubstituted benzoic acid, alkali metal salt (PMN P-03-643) is subject to...

2013-07-01

22

40 CFR 721.10399 - Benzoic acid azo-substituted pyridine (generic).  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Benzoic acid azo-substituted pyridine (generic...Chemical Substances § 721.10399 Benzoic acid azo-substituted pyridine (generic...substance identified generically as benzoic acid azo-substituted...

2013-07-01

23

40 CFR 721.10555 - Benzoic acid nonyl ester, branched and linear.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Benzoic acid nonyl ester, branched and linear...Chemical Substances § 721.10555 Benzoic acid nonyl ester, branched and linear...chemical substance identified as benzoic acid nonyl ester, branched...

2013-07-01

24

The anaerobic decomposition of benzoic acid during methane fermentation  

Microsoft Academic Search

Anaerobic rupture of the benzoic acid ring was investigated. Carbon 4 was converted primarily to carbon dioxide. Following ring rupture during methane fermentation, propanoic acid is an intermediate, and carbon 4 of benzoate becomes its carboxyl.

L. R. Fina; R. L. Bridges; T. H. Coblentz; F. F. Roberts

1978-01-01

25

The anaerobic decomposition of benzoic acid during methane fermentation  

Microsoft Academic Search

A possible pathway for the anaerobic utilization of benzoic acid by a methanogenic consortium is suggested. Cyclohexane carboxylic acid and 1-cyclohexene-1-carboxylic acid have been identified as intermediates before ring rupture. Surprisingly, 3-cyclohexene-1-carboxylic acid interferes with utilization of other cyclic acids. In addition, isobutyric acid or short chain acids containing carbon-carbon double bonds could not be used without induction periods of

C. L. Keith; R. L. Bridges; L. R. Fina; K. L. Iverson; J. A. Cloran

1978-01-01

26

Effect of valproic acid on glycine conjugation of benzoic acid.  

PubMed

Conjugation with glycine proceeds through ATP-dependent coupling of carboxylic acids with coenzyme A (CoA). Therefore, chemicals that form CoA esters may interfere with glycine conjugation. We tested the hypothesis that valproic acid (VPA), which is esterified with CoA in the first step of its mitochondrial beta-oxidation, may compromise glycine conjugation of aromatic carboxylic acids, by investigating the effect of acute VPA administration on glycine conjugation of benzoic acid in rats. VPA administered 1 hr before injection of benzoate only decreased the blood clearance of benzoate and the urinary excretion of benzoylglycine slightly in normal rats. However, in rats loaded with glycine, 2 and 3 mmol/kg of VPA reduced the blood clearance of benzoate by 34 and 59%, diminished the peak blood level of the glycine conjugate and depressed the maximal urinary excretion rate of benzoylglycine by 28 and 66%, respectively. To elucidate the mechanism of VPA-induced inhibition of benzoylglycine formation, the effects of VPA on hepatic levels of cosubstrates and the activities of enzymes involved in glycine conjugation were also determined. One hour after administration of VPA, hepatic ATP levels remained unchanged, whereas the concentration of CoA was reduced by 67 to 73% and that of glycine was increased by 58 to 67%. Activities of the enzymes of glycine conjugation were not influenced by VPA. However, 2-n-propyl-4-pentenoic acid, a metabolite of VPA, inhibited benzoyl-CoA synthetase. In summary, VPA minimally influenced the capacity of glycine conjugation of benzoic acid in normal rats, but decreased it markedly in glycine-loaded rats.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8263766

Gregus, Z; Fekete, T; Varga, F; Klaassen, C D

1993-12-01

27

Uptake of Benzoic Acid and Chloro-Substituted Benzoic Acids byAlcaligenes denitrificansBRI 3010 and BRI 6011  

Microsoft Academic Search

The mechanism of uptake of benzoic and 2,4-dichlorobenzoic acid (2,4-DCBA) by Alcaligenes denitrificans BRI3010andBRI6011andPseudomonassp.strainB13,threeorganismscapableofdegradingvariousisomers ofchlorinatedbenzoicacids,wasinvestigated.Inallthreeorganisms,uptakeofbenzoicacidwasinducible.For benzoic acid uptake into BRI 3010, monophasic saturation kinetics with apparentKmandVmaxvalues of 1.4 mM and 3.2 nmol\\/min\\/mg of cell dry weight, respectively, were obtained. For BRI 6011, biphasic saturation kinetics were observed, suggesting the presence of two uptake systems for benzoic acid with distinctKm(0.72 and

CARLOS B. MIGUEZ; CHARLES W. GREER; JORDAN M. INGRAM; ANDROBERT A. MACLEOD

28

Surface interaction of benzoic acid with a copper electrode  

Microsoft Academic Search

Adsorption of benzoic acid at copper electrodes, obtained by electroplating copper on gold, has been studied in 0.1 M HClO4 using a radiotracer technique and cyclic voltammetry. Impedance spectroscopy has been applied to verify the real surface area of copper electrodes also determined from voltammetric data in the double-layer region.Radiotracer measurements of adsorption have indicated that benzoic acid is surface

P. Waszczuk; P. Zelenay; J. Sobkowski

1995-01-01

29

40 CFR 721.10109 - Hexanoic acid, 2-ethyl-, mixed triesters with benzoic acid and trimethylolpropane.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Hexanoic acid, 2-ethyl-, mixed triesters with benzoic acid and trimethylolpropane. 721.10109 Section...Chemical Substances § 721.10109 Hexanoic acid, 2-ethyl-, mixed triesters with...

2013-07-01

30

Benzoic acid and substituted benzoic acids as interfacial corrosion inhibitors for copper in HClO 4  

Microsoft Academic Search

Corrosion of copper in HClO4 solution containing various concentrations (10-710-4 M) of benzoic acid,p-toluic acid,p-nitrobenzoic acid, phthalic acid and terephthalic acid has been studied at 30 C. These compounds inhibit corrosion effectively even in trace concentration. The corrosion rate is a function of temperature, concentration and nature of the inhibitor. The inhibitor efficiency calculated from weight loss and polarization methods

R. K. Dinnappa; S. M. Mayanna

1981-01-01

31

Degradation of Phthalic Acids and Benzoic Acid from Terephthalic Acid Wastewater by Advanced Oxidation Processes  

Microsoft Academic Search

Terephthalic acid (TPA) wastewater is traditionally being treated by biological method. This study investigates the degradation of three major toxic target organic species, namely terephthalic acid (TPA), isophthalic acid (IPA), benzoic acid (BA), present in the TPA wastewater, by several advanced oxidation processes. The performance of three main oxidation processes such as photofenton oxidation (UV-H2O2-Fe), photocatalytic ozonation (UV-O3-Fe) and photofenton

Ramesh Thiruvenkatachari; Tae Ouk Kwon; Il Shik Moon

2006-01-01

32

Determination of benzoic acid, chlorobenzoic acids and chlorendic acid in water  

SciTech Connect

To characterize and conduct treatment studies of a landfill leachate an analysis procedure was required to determine concentrations of benzoic acid, the three isomers of chlorobenzoic acid and chlorendic acid. The title compounds were isolated from acidified (pH 1) water by extraction with methyl t-butyl ether. Analytes were concentrated by back-extracting the ether with 0.1 N sodium hydroxide which was separated and acidified. This solution was analyzed by C[sub 18] reversed-phase HPLC with water/acetonitrile/acetic acid eluent and UV detection at 222 nm. The method has detection limits of 200 [mu]g/L for chlorendic acid and 100 [mu]g/L for benzoic acid and each isomer of chlorobenzoic acid. Validation studies with water which was fortified with the analytes at concentrations ranging from one to ten times detection limits resulted in average recoveries of >95%.

Dietz, E.A.; Cortellucci, N.J.; Singley, K.F. (Occidental Chemical Corp., Grand Island, NY (United States))

1993-01-01

33

Ionization of aqueous benzoic acid: Conductance and thermodynamics  

Microsoft Academic Search

Molar conductances of dilute aqueous benzoic acid solutions are presented for temperatures from 5 to 80C. The data have been analyzed to give acid dissociation constants as well as ?Ho, ?So, and ?Cpo for the ionization process and the limiting conductance of the benzoate ion. The conductance-viscosity product changes less than 4% over the temperature range, indicating that the interaction

Laurence E. Strong; Thomas Kinney; Paul Fischer

1979-01-01

34

Benzoic acid as a natural compound in cultured dairy products and cheese  

Microsoft Academic Search

This review deals with the state of the art of benzoic acid in cultured dairy products and cheese. During fermentation, benzoic acid is produced from hippuric acid, a component of milk naturally present at concentrations of up to 50 mg\\/kg. In smearripened cheese, however, higher benzoic acid concentrations have often been measured on the surface or even inside such cheeses.

R Sieber; U Btikofer; J. O Bosset

1995-01-01

35

QSAR study of the toxicity of benzoic acids to Vibrio fischeri, Daphnia magna and carp  

Microsoft Academic Search

The toxicities of benzoic acids to Vibrio fischeri, Daphnia magna and carp were measured. The results showed that the toxicity to V. fischeri and Daphnia decreased in the order of bromo>chloro>fluoro?aminobenzoic acids. The toxicity of substituted benzoic acids to carp and Daphnia was much lower than that to V. fischeri. The results also showed that the toxicity of benzoic acids

Y. H. Zhao; G. D. Ji; M. T. D. Cronin; J. C. Dearden

1998-01-01

36

40 CFR 721.10202 - Benzoic acid, 4-chloro-2- [(substituted)azo]-, strontium salt (1:1) (generic).  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Benzoic acid, 4-chloro-2- [(substituted...Chemical Substances § 721.10202 Benzoic acid, 4-chloro-2- [(substituted...substance identified generically as benzoic acid, 4-chloro-2-...

2013-07-01

37

Uptake of Benzoic Acid and Chloro-Substituted Benzoic Acids by Alcaligenes denitrificans BRI 3010 and BRI 6011  

PubMed Central

The mechanism of uptake of benzoic and 2,4-dichlorobenzoic acid (2,4-DCBA) by Alcaligenes denitrificans BRI 3010 and BRI 6011 and Pseudomonas sp. strain B13, three organisms capable of degrading various isomers of chlorinated benzoic acids, was investigated. In all three organisms, uptake of benzoic acid was inducible. For benzoic acid uptake into BRI 3010, monophasic saturation kinetics with apparent K(infm) and V(infmax) values of 1.4 (mu)M and 3.2 nmol/min/mg of cell dry weight, respectively, were obtained. For BRI 6011, biphasic saturation kinetics were observed, suggesting the presence of two uptake systems for benzoic acid with distinct K(infm) (0.72 and 5.3 (mu)M) and V(infmax) (3.3 and 4.6 nmol/min/mg of cell dry weight) values. BRI 3010 and BRI 6011 accumulated benzoic acid against a concentration gradient by a factor of 8 and 10, respectively. A wide range of structural analogs, at 50-fold excess concentrations, inhibited benzoic acid uptake by BRI 3010 and BRI 6011, whereas with B13, only 3-chlorobenzoic acid was an effective inhibitor. For BRI 3010 and BRI 6011, the inhibition by the structural analogs was not of a competitive nature. Uptake of benzoic acid by BRI 3010 and BRI 6011 was inhibited by KCN, by the protonophore 3,5,3(prm1), 4(prm1)-tetrachlorosalicylanilide (TCS), and, for BRI 6011, by anaerobiosis unless nitrate was present, thus indicating that energy was required for the uptake process. Uptake of 2,4-DCBA by BRI 6011 was constitutive and saturation uptake kinetics were not observed. Uptake of 2,4-DCBA by BRI 6011 was inhibited by KCN, TCS, and anaerobiosis even if nitrate was present, but the compound was not accumulated intracellularly against a concentration gradient. Uptake of 2,4-DCBA by BRI 6011 appears to occur by passive diffusion into the cell down its concentration gradient, which is maintained by the intracellular metabolism of the compound. This process could play an important role in the degradation of xenobiotic compounds by microorganisms.

Miguez, C. B.; Greer, C. W.; Ingram, J. M.; MacLeod, R. A.

1995-01-01

38

Uptake of Benzoic Acid and Chloro-Substituted Benzoic Acids by Alcaligenes denitrificans BRI 3010 and BRI 6011.  

PubMed

The mechanism of uptake of benzoic and 2,4-dichlorobenzoic acid (2,4-DCBA) by Alcaligenes denitrificans BRI 3010 and BRI 6011 and Pseudomonas sp. strain B13, three organisms capable of degrading various isomers of chlorinated benzoic acids, was investigated. In all three organisms, uptake of benzoic acid was inducible. For benzoic acid uptake into BRI 3010, monophasic saturation kinetics with apparent K(infm) and V(infmax) values of 1.4 (mu)M and 3.2 nmol/min/mg of cell dry weight, respectively, were obtained. For BRI 6011, biphasic saturation kinetics were observed, suggesting the presence of two uptake systems for benzoic acid with distinct K(infm) (0.72 and 5.3 (mu)M) and V(infmax) (3.3 and 4.6 nmol/min/mg of cell dry weight) values. BRI 3010 and BRI 6011 accumulated benzoic acid against a concentration gradient by a factor of 8 and 10, respectively. A wide range of structural analogs, at 50-fold excess concentrations, inhibited benzoic acid uptake by BRI 3010 and BRI 6011, whereas with B13, only 3-chlorobenzoic acid was an effective inhibitor. For BRI 3010 and BRI 6011, the inhibition by the structural analogs was not of a competitive nature. Uptake of benzoic acid by BRI 3010 and BRI 6011 was inhibited by KCN, by the protonophore 3,5,3(prm1), 4(prm1)-tetrachlorosalicylanilide (TCS), and, for BRI 6011, by anaerobiosis unless nitrate was present, thus indicating that energy was required for the uptake process. Uptake of 2,4-DCBA by BRI 6011 was constitutive and saturation uptake kinetics were not observed. Uptake of 2,4-DCBA by BRI 6011 was inhibited by KCN, TCS, and anaerobiosis even if nitrate was present, but the compound was not accumulated intracellularly against a concentration gradient. Uptake of 2,4-DCBA by BRI 6011 appears to occur by passive diffusion into the cell down its concentration gradient, which is maintained by the intracellular metabolism of the compound. This process could play an important role in the degradation of xenobiotic compounds by microorganisms. PMID:16535175

Miguez, C B; Greer, C W; Ingram, J M; Macleod, R A

1995-12-01

39

Uptake of benzoic acid and chloro-substituted benzoic acids by alcaligenes denitrificans BRI 3010 and BRI 6011  

SciTech Connect

The mechanism of uptake of benzoic and 2,4-dichlorobenzoic acid (2,4-DCBA) by Alcaligenes denitrificans BRI 3010 and BRI 6011 and Pseudomonas sp. strain B13, three organisms capable of degrading isomers of chlorinated benzoic acids, was investigated. In all three organisms, uptake of benzoic acid was inducible. For benzoic acid uptake into BRI 3010, monophasic saturation kinetics with apparent K{sub m} and V{sub max} values of 1.4 {mu}M and 3.2 nmol/min/mg of cell dry weight, respectively, were obtained. For BRI 6011, biphasic saturation kinetics were observed, suggesting presence of two uptake systems for benzoic acid with distinct K{sub m} (0.72 and 5.3 {mu}M) and V{sub max} (3.3 and 4.6 nmol/min/mg of cell dry weight) values. BRI 3010 and BRI 6011 accumulated benzoic acid against a concentration gradient by a factor of 8 and 10, respectively. A wide range of structural analogs, at 50-fold excess concentrations, inhibited benzoic acid uptake by BRI 3010 and BRI 6011, whereas with B13, only 3-chlorobenzoic acid was an effective inhibitor. For BRI 3010 and BRI 6011, the inhibition by the structural analogs was not of a competitive nature. Uptake of benzoic acid by BRI 3010 and BRI 6011 was inhibited by KCN, by the protonophore 3,5,3`, 4`-tetrachlorosalicylanilide (TCS), and, for BRI 6011, by anaerobiosis unless nitrate was present, thus indicating that energy was required for the uptake process. Uptake of 2,4-DCBA by BRI 6011 was constitutive and saturation uptake kinetics were not observed. Uptake of 2,4-DCBA by BRI 6011 was inhibited by KCN, TCS, and anaerobiosis even if nitrate was present, but the compound was not accumulated intracellularly against a concentration gradient. Uptake of 2,4-DCBA by BRI 6011 appears to occur by passive diffusion into the cell down its concentration gradient, which is maintained by the intracellular metabolism of the compound. This process could play an important role in the degradation of xenobiotic compounds by microorganisms.

Miguez, C.B.; Ingram, J.M.; MacLeod, R.A. [McGill Univ., Quebec (Canada)] [and others

1995-12-01

40

Estimating the acidity of singly and multiply substituted benzoic acids via electrostatic potential at the nucleus  

NASA Astrophysics Data System (ADS)

A good linear relationship between MEP and the experimental p K a data has been revealed for substituted benzoic acids. We established two good linear relationships between p K a vs MEP by DFT methods. We used two models to predict the p K a values for 20 substituted benzoic acids. It has potential applications in estimating p K a of amino acids/macromolecules.

Zhong, Ai-Guo; Jiang, Hua-Jiang; Liang, Hua-Ding

2011-08-01

41

Water as a hydrogen atom donor in benzoic acid decarboxylation  

Microsoft Academic Search

The interaction of D2O vapors with benzoic acid decarboxylation products over a vanadium-titanium oxide catatlyst at 400460C has been studied. Benzene formation is due to the participation of water in the reaction as a donor of deuterium atoms:\\u000a$$PhCOOH \\\\to Ph;Ph + D - OD \\\\to PhD + DO \\\\cdot $$

D. Kh. Sembaev; B. V. Suvorov; A. B. Makhmetov; O. V. Agashkin

1978-01-01

42

Study on QSTR of Benzoic Acid Compounds with MCI  

PubMed Central

Quantitative structure-toxicity relationship (QSTR) plays an important role in toxicity prediction. With the modified method, the quantum chemistry parameters of 57 benzoic acid compounds were calculated with modified molecular connectivity index (MCI) using Visual Basic Program Software, and the QSTR of benzoic acid compounds in mice via oral LD50 (acute toxicity) was studied. A model was built to more accurately predict the toxicity of benzoic acid compounds in mice via oral LD50: 39 benzoic acid compounds were used as a training dataset for building the regression model and 18 others as a forecasting dataset to test the prediction ability of the model using SAS 9.0 Program Software. The model is LogLD50 = 1.2399 0JA +2.6911 1JA 0.4445 JB (R2 = 0.9860), where 0JA is zero order connectivity index, 1JA is the first order connectivity index and JB = 0JA 1JA is the cross factor. The model was shown to have a good forecasting ability.

Li, Zuojing; Sun, Yezhi; Yan, Xinli; Meng, Fanhao

2010-01-01

43

The biosynthesis of benzoic acid glucosinolate esters in Arabidopsis thaliana  

Microsoft Academic Search

The siliques and seeds of Arabidopsis thaliana accumulate a series of glucosinolates containing an alkyl side chain of varying length with a terminal benzoate ester function. The biosynthesis of these unusual nitrogen- and sulfur-containing natural products was investigated by feeding isotopically-labeled precursors to detached flowering stems. Glucosinolates were extracted, purified and analyzed by tandem mass spectrometry. Phenylalanine and benzoic acid

Gerson Graser; Neil J. Oldham; Paul D. Brown; Ulrike Temp; Jonathan Gershenzon

2001-01-01

44

Adsorptive crystallization of benzoic acid in aerogels from supercritical solutions  

Microsoft Academic Search

In this work, adsorption and crystallization of benzoic acid in different porous carriers (silica aerogel, MCM41, Trisopor glass, zeolite) from supercritical CO2 solutions is studied. The main purpose is to reveal the influence of the adsorptive properties of the carrier on the crystallization behavior of the solute. Therefore, both adsorption and crystallization processes are studied as a function of carrier's

B. S. K. Gorle; I. Smirnova; W. Arlt

2010-01-01

45

Direct ortho-arylation of ortho-substituted benzoic acids: overriding Pd-catalyzed protodecarboxylation.  

PubMed

ortho-Arylation of ortho-substituted benzoic acids is a challenging process due to the tendency of the reaction products toward Pd-catalyzed protodecarboxylation. A simple method for preventing decarboxylation in sterically hindered benzoic acids is reported. The method described represents a reliable and broadly applicable entry to 2-aryl-6-substituted benzoic acids. PMID:23373630

Arroniz, Carlos; Ironmonger, Alan; Rassias, Gerry; Larrosa, Igor

2013-02-01

46

The Influences of Structural Evolution of Silica Gel Glass on the Photophysical Properties of Benzoic Acid  

Microsoft Academic Search

Benzoic acid was dispersed into silica gel glass at molecular level by sol-gel process. The luminescence properties of benzoic acid in gel glass heat-treated at various temperatures were studied. The changes in gel glass structure and the surrounding environment of benzoic acid resulted in different electronic transitions, and thus the different luminescence spectra. The fluorescence bands centered at 320 nm

Guodong Qian; Zhiyu Wang; Minquan Wang

2002-01-01

47

Studies on the anaerobic degradation of benzoic acid and 2-aminobenzoic acid by a denitrifying Pseudomonas strain  

Microsoft Academic Search

The growth of a denitrifying Pseudomonas strain on benzoic acid and 2-aminobenzoic acid (anthranilic acid) has been studied. The organism grew aerobically on benzoate, 2-aminobenzoate, and gentisate, but not on catechol or protocatechuic acid. These and other findings suggest that aerobic degradation of benzoic acid was via gentisic acid. Under completely anaerobic conditions in the presence of nitrate, benzoate and

K. Ziegler; K. Braun; A. Biickler; G. Fuchs

1987-01-01

48

New prenylated benzoic acid derivatives of Piper hispidum.  

PubMed

Three new 4-hydroxy-benzoic acid derivatives, 4-methoxy-3,5-bis-(3-hydroxy-3-methyl-1-butenyl)benzoate, 3-hydroxy-2-(1-hydroxy-1-methylethyl)-2,3-dihydrobenzofuran-5-carboxylic acid, and 3-hydroxy-2-(1-hydroxy-1-methylethyl)-2,3-dihydrobenzofuran-5-carboxylic acid methyl ester together with eight known compounds, have been isolated from the stems of Piper hispidum. Their structures were elucidated by a detailed spectroscopic analysis. In addition, the cytotoxicity of seven isolated compounds has been evaluated, revealing a moderate activity for three derivatives of dillapiole. PMID:15997836

Friedrich, U; Siems, K; Solis, P N; Gupta, M P; Jenett-Siems, K

2005-06-01

49

4-(Cyclo-propane-carboxamido)-benzoic acid  

PubMed Central

In the title compound, C11H11NO3, the dihedral angle between the benzene ring and the cyclopropane ring is 63.2?(1). In the crystal, molecules are linked through classical cyclic carboxylic acid OH?O hydrogen-bond interactions [graph set R 2 2(8)] giving centrosymmetric dimers which are extended along the b-axis direction through amide NH?O hydrogen-bond interactions, giving one-dimensional ribbon structures. Weak CH?O interactions are also present in the structure.

Sun, Zhong-Qiang; Ding, Zhen-Ya; Shao, Zhi-Yu

2012-01-01

50

Production of cis,cis -muconic acid from benzoic acid via microbial transformation  

Microsoft Academic Search

For the production ofcis,cis-muconic acidvia biocatalytic conversion reactions from a toxic cosubstrate, benzoic acid, a fed-batch process using computer-controlled DO-stat\\u000a feeding was developed. The mutant strain ofPseudomonas putida BM014 producedcis,cis-muconic acid from benzoic acid with high conversion yield. More than 32 g\\/L ofcis,cis-muconic acid was accumulated in 42h and a productivity of 1.4 g\\/(Lh) was achieved.

Sang Gu Bang; Won Jae Choi; Cha Yong Choi; Moo Hwan Cho

1996-01-01

51

IUPAC-NIST Solubility Data Series. 99. Solubility of Benzoic Acid and Substituted Benzoic Acids in Both Neat Organic Solvents and Organic Solvent Mixtures  

NASA Astrophysics Data System (ADS)

Solubility data are compiled and reviewed for benzoic acid and 63 substituted benzoic acids dissolved in neat organic solvents and well-defined binary and ternary organic solvent mixtures. The compiled solubility data were retrieved from the published chemical and pharmaceutical literature covering the period from 1900 to the beginning of 2013.

Acree, William E.

2013-09-01

52

Luminescence of benzoic acid polycrystals doped with n-terphenyl and n-quaterphenyl  

SciTech Connect

The luminescence and luminescence excitation spectra of benzoic acid polycrystals, terphenyl, quaterphenyl, and benzoic acid doped with terphenyl and quaterphenyl are studied. Blue shifts of the fluorescence and fluorscence excitation spectra are found. These shifts result from nonplanar entering of polyphenyl molecules into the unit cell of the benzoic acid dimmers around the acid carbonyl groups. In the impurity polycrystals at room temperature, the internal conversion from the triplet level efficiently occurs resulting in the absence of phosphorescence. 12 refs., 4 figs.

Zarochentseva, E.P.; Korotkov, V.I.; Oleinik, Y.P. [St. Petersburg State Univ. (Russian Federation)] [and others

1994-10-01

53

Benzoic acid biosynthesis in cell cultures of Hypericum androsaemum  

Microsoft Academic Search

Biosynthesis of benzoic acid from cinnamic acid has been studied in cell cultures of Hypericum androsaemum L. The mechanism underlying side-chain shortening is CoA-dependent and non-#-oxidative. The enzymes involved are cinnamate:CoA ligase, cinnamoyl-CoA hydratase\\/lyase and benzaldehyde dehydrogenase. Cinnamate:CoA ligase was separated from benzoate:CoA ligase and 4-coumarate:CoA ligase, which belong to xanthone biosynthesis and general phenylpropanoid metabolism, respectively. Cinnamoyl-CoA hydratase\\/lyase catalyzes

Ahmed M. Abd El-Mawla; Ludger Beerhues

2002-01-01

54

Characteristics of the binary faceted eutectic: benzoic acid - salicylic acid system  

Microsoft Academic Search

The consistent symmetry relations computed from the heterogeneous nucleation data of the non-ideal benzoic acid - salicylic acid eutectic system verifies the validity of nucleation theory. The kinetics of crystal growth from the molten state of the system follows the dislocation mechanism. Anomalous behaviour of both viscosity and activation energy for the eutectic melt confirms the essence of specific interactions

B. L. Sharma; S. Tandon; S. Gupta

2009-01-01

55

Thermodynamic and lamella models relationship for the eutectic system benzoic acid cinnamic acid  

Microsoft Academic Search

The present investigation reveals the relationship between excess thermodynamic functions and the growth habits of the eutectic phases from the melt by continuous melt-growth technique. Excess thermodynamic functions computed for different compositions of the benzoic acid - cinnamic acid eutectic system have been found consistent with the criteria of spontaneity and Planck formulation, and their reliability has been ascertained by

B. L. Sharma; R. Jamwal; R. Kant

2004-01-01

56

Lipoic acid impairs glycine conjugation of benzoic acid and renal excretion of benzoylglycine.  

PubMed

Glycine conjugation of benzoic acid is catalyzed by the mitochondrial enzymes benzoyl-coenzyme A(CoA) synthetase and benzoyl-CoA: glycine N-acyltransferase and requires ATP, CoA, and glycine as cosubstrates. Lipoic acid (LA), an important endogenous and also therapeutic compound, depletes hepatic CoA; therefore, it may interfere with glycine conjugation. To test this hypothesis, LA (0.5-1.5 mmol/kg ip) was given to anesthetized, glycine-loaded rats 1 hr before administration of benzoic acid (1 mmol/kg iv). LA inhibited glycine conjugation of benzoic acid in a dose-dependent manner as indicated by: 1) reduced clearance of benzoic acid from blood; 2) delayed appearance of benzoylglycine in blood; and 3) decreased excretion of benzoylglycine in urine. LA also decreased urinary excretion of injected benzoylglycine, indicating that reduced excretion of this metabolite after benzoic acid injection is caused by diminished formation and impaired renal transport of benzoylglycine. Urine formation was decreased by LA in a dose-dependent fashion, and acute renal failure was evident in rats receiving the highest dose. LA depleted hepatic CoA, carnitine, and glutathione, but not ATP, whereas it increased the hepatic concentration of glycine. In isolated and solubilized rat liver mitochondria, LA inhibited both benzoyl-CoA synthetase (IC50 approximately 1.5 mM) and benzoyl-CoA:glycine N-acyltransferase (IC50 approximately 0.3 mM). Thus, depletion of CoA and inhibition of the pertinent enzymes seem responsible for impairment of glycine conjugation of benzoic acid by LA. LA may also impair renal tubular cell function, compromising the tubular secretion of benzoylglycine and causing acute renal failure. PMID:8781786

Gregus, Z; Fekete, T; Halszi, E; Klaassen, C D

1996-06-01

57

40 CFR 721.10111 - Hexanoic acid, 2-ethyl-, mixed diesters with benzoic acid and diethylene glycol.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Hexanoic acid, 2-ethyl-, mixed diesters with benzoic acid and diethylene glycol. 721.10111 Section...Chemical Substances § 721.10111 Hexanoic acid, 2-ethyl-, mixed diesters with...

2013-07-01

58

40 CFR 721.10110 - Hexanoic acid, 2-ethyl-, mixed diesters with benzoic acid and neopentlyl glycol.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Hexanoic acid, 2-ethyl-, mixed diesters with benzoic acid and neopentlyl glycol. 721.10110 Section...Chemical Substances § 721.10110 Hexanoic acid, 2-ethyl-, mixed diesters with...

2013-07-01

59

40 CFR 721.1705 - Benzoic acid, 3-amino-, diazotized, coupled with 6-amino-4-hydroxy-2-naphthalenesulfonic acid...  

Code of Federal Regulations, 2013 CFR

Benzoic acid, 3-amino-, diazotized, coupled with 6-amino-4-hydroxy-2-naphthalenesulfonic acid, diazotized, (3-aminophenyl)phosphonic acid and diazotized 2,5-diethoxybenzenamine. 721.1705 Section 721.1705 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY...

2013-07-01

60

Determination of Benzoic and Sorbic Acids in Labaneh by High-Performance Liquid Chromatography  

Microsoft Academic Search

Benzoic and sorbic acid contents of 14 packaged commercial labaneh (concentrated set yogurt) samples were determined by HPLC method using a reverse phase C-18 column and a mobile phase of 90:10, phosphate buffer:methanol. There was a linear relationship between peak area versus benzoic and sorbic acids concentrations between 32 and 300 mg\\/l. Recoveries of benzoic acid added at 318 and

Ghadeer F. Mihyar; Ali K. Yousif; Mohammed I. Yamani

1999-01-01

61

Sodium and potassium benzoate and benzoic acid as eluents for ion chromatography  

SciTech Connect

Benzoic acid is introduced as an eluent and is compared with benzoate salt eluents. Detector response to sample ions in single-column ion chromatogrphy is compared with dual-column (suppressed) ion chromatography. Benzoic acid has a higher background conductance; however, samples separated with benzoate salt eluents. Comparable sample peak areas are found with suppressor column treated benzoate eluents and benzoic acid eluents. Equations are described which predict detector response for a variety of conditions.

Gjerde, D.T.; Fritz, J.S.

1981-12-01

62

Adsorption of phenol and benzoic acid from dilute aqueous solution onto macroreticular resin  

Microsoft Academic Search

The adsorption of phenol and benzoic acid from dilute aqueous solution onto macroreticular resin was studied by a radiotracer technique for 0.4948-0.0003 mg\\/ml benzoic acid solutions at 25°C and for similar concentrations of phenol at 0°, 25°, and 70°C. Adsorption equilibrium with the Amberlite XAD-8 resin slurry was reached after 44 hr for benzoic acid and after 104 hr for

D. S. Farrier; A. L. Hines; S. W. Wang

1979-01-01

63

Application of a supported iron oxyhydroxide catalyst in oxidation of benzoic acid by hydrogen peroxide  

Microsoft Academic Search

Oxidation of benzoic acid was studied via Fenton-like reaction using an innovative supported ?-FeOOH catalyst. The decomposition kinetics of hydrogen peroxide was investigated first. Oxidation of benzoic acid by hydrogen peroxide was performed to understand the effects of initial pH and hydrogen peroxide dosage. The treatment efficiency of benzoic acid at an initial pH of 3.2 was higher than at

Shanshan Chou; Chihpin Huang

1999-01-01

64

Absorption of sorbic and benzoic acids in the flesh of table olives  

Microsoft Academic Search

The distribution of sorbic and benzoic acids in the different phases of table olives was studied. To a large extent, these preservatives accumulated in the oil phase of fruits stored in acid conditions, as well as in juice and other tissue components. Thus, around 2030% of the benzoic acid in olives was found in the juice phase, 3050% in the

Manuel Brenes; Concepcin Romero; Pedro Garca; Antonio Garrido

2004-01-01

65

Benzoic acid 2-hydroxylase, a soluble oxygenase from tobacco, catalyzes salicylic acid biosynthesis  

SciTech Connect

Benzoic acid 2-hydroxylase (BA2H) catalyzes the biosynthesis of salicylic acid from benzoic acid. The enzyme has been partially purified and characterized as a soluble protein of 160 kDa. High-efficiency in vivo labeling of salicyclic acid with {sup 18}O{sub 2} suggested that BA2H is an oxygenase that specifically hydroxylates the ortho position of benzoic acid. The enzyme was strongly induced by either tobacco mosaic virus inoculation of benzoic acid infiltration of tobacco leaves and it was inhibited by CO and other inhibitors of cytochrome P450 hydroxylases. The BA2H activity was immunodepleted by antibodies raised against SU2, a soluble cytochrome P450 from Streptomyces griseolus. The anti-SU2 antibodies immunoprecipitated a radiolabeled polypeptide of around 160 kDa from the soluble protein extracts of L-[{sup 35}S]-methionine-fed tobacco leaves. Purified BA2H showed CO-difference spectra with a maximum at 457 nm. These data suggest that BA2H belongs to a novel class of soluble, high molecular weight cytochrome P450 enzymes. 21 refs., 6 figs., 1 tab.

Leon, J.; Shulaev, V.; Yalpani, N. [Rutgers Univ., New Brunswick, NJ (United States)] [and others

1995-10-24

66

Palladium-Catalyzed Chemoselective Decarboxylative Ortho Acylation of Benzoic Acids with ?-Oxocarboxylic Acids.  

PubMed

Palladium-catalyzed chemoselective decarboxylative cross coupling of benzoic acids with ?-oxocarboxylic acids was realized via an arene sp(2) C-H functionalization process. This work represents the first example of transition-metal-catalyzed cross-coupling reactions with two acids acting in different roles. The synthetic utility of this method was confirmed by the synthesis of pitofenone, an antispasmodic used in the combined drug Spasmalgon. PMID:23721458

Miao, Jinmin; Ge, Haibo

2013-05-30

67

(E)-2-(Isonicotinoylhydrazonometh-yl)benzoic acid methanol monosolvate  

PubMed Central

The title compound, C14H11N3O3CH4O, was synthesized by the condensation reaction of isonicotinohydrazide with an equimolar quantity of 2-formylbenzoic acid in methanol. The hydrazone molecule displays an E configuration about the C=N bond. The dihedral angel between the pyridine and the benzene rings is 12.04?(5). In the crystal structure, molecules are linked by OH?N, OH?O and NH?O hydrogen-bonding interactions.

Li, Wenkuan; Yin, Handong; Wen, Liyuan; Cui, Jichun; Wang, Daqi

2009-01-01

68

Investigation on terahertz vibrational modes of crystalline benzoic acid  

NASA Astrophysics Data System (ADS)

The characteristic absorption features of crystalline benzoic acid in 0.1-4.0 THz have been measured by terahertz time-domain spectroscopy experimentally. Three sharp and low-intensity peaks are observed in the lowest frequency range of 0.1-1.5 THz. In particular, the absorption peak at 0.63 THz is reported for the first time, to the best of our knowledge. Moreover, theoretical simulations have also been performed, and all measured terahertz absorption features are unambiguously assigned. Our calculations clearly show that the first three absorption features arise from translation motions of dimers held together by hydrogen bonds.

Yan, Hui; Fan, Wen-Hui; Zheng, Zhuan-Ping

2012-03-01

69

Salicylic Acid sans Aspirin in Animals and Man: Persistence in Fasting and Biosynthesis from Benzoic Acid  

PubMed Central

Salicylic acid (SA), which is central to defense mechanisms in plants and the principal metabolite of aspirin, occurs naturally in man with higher levels of SA and its urinary metabolite salicyluric acid (SU) in vegetarians overlapping with levels in patients on low-dose aspirin regimens. SA is widely distributed in animal blood. Fasting for major colorectal surgery did not cause disappearance of SA from plasma, even in patients following total proctocolectomy. A 13C6 benzoic acid load ingested by six volunteers led, between 8 and 16 h, to a median 33.9% labeling of urinary salicyluric acid. The overall contribution of benzoic acid (and its salts) to the turnover of circulating SA thus requires further assessment. However, that SA appears to be, at least partially, an endogenous compound should lead to reassessment of its role in human (and animal) pathophysiology.

2008-01-01

70

Salicylic acid sans aspirin in animals and man: persistence in fasting and biosynthesis from benzoic acid.  

PubMed

Salicylic acid (SA), which is central to defense mechanisms in plants and the principal metabolite of aspirin, occurs naturally in man with higher levels of SA and its urinary metabolite salicyluric acid (SU) in vegetarians overlapping with levels in patients on low-dose aspirin regimens. SA is widely distributed in animal blood. Fasting for major colorectal surgery did not cause disappearance of SA from plasma, even in patients following total proctocolectomy. A (13)C(6) benzoic acid load ingested by six volunteers led, between 8 and 16 h, to a median 33.9% labeling of urinary salicyluric acid. The overall contribution of benzoic acid (and its salts) to the turnover of circulating SA thus requires further assessment. However, that SA appears to be, at least partially, an endogenous compound should lead to reassessment of its role in human (and animal) pathophysiology. PMID:19053387

Paterson, John R; Baxter, Gwendoline; Dreyer, Jacob S; Halket, John M; Flynn, Robert; Lawrence, James R

2008-12-24

71

Role of hydroxyl group in the inhibitive action of benzoic acid toward corrosion of aluminum in nitric acid  

SciTech Connect

Corrosion inhibition action of benzoic acid, p-hydroxy benzoic acid, 2-4-dihydroxy benzoic acid, and 3-4-5-trihydroxy benzoic acid toward aluminum alloy 3003 (UNS A93003) in 20% (wt%) nitric acid (HNO{sub 3}) using different concentrations of these compounds at 30 C, 40 C, and 50 C has been studied thoroughly. 3-4-5-trihydroxy benzoic acid (inhibition efficiency (IE): 30% and 72%) was the most effective inhibitor followed by 2-4-dihydroxy benzoic acid (IE: 22% to 62%) p-hydroxy benzoic acid (IE: 11% to 52%), and benzoic acid (IE: 2.5% to 15%). IE increased with concentration and its maximum value was observed at 0.5% concentration of all inhibitors used. The percentage of IE of the inhibitors decreased with an increase in temperature from 30 C to 50 C. Values of heat adsorption and activation energy were calculated from weight loss data, which came out in the range for the reaction occurring at the surface. The behavior of inhibitors studied deviated from the Langmuir isotherm. The IE of higher hydroxy species was improved when more hydroxy centers were added. Anodic and cathodic polarization curves were shifted toward lower current density regions in the presence of inhibitors. This revealed that they were mixed inhibitors.

Yadav, P.N.S.; Singh, A.K.; Wadhwani, R.

1999-10-01

72

The effects of benzoic acid supplementation on the performance of broiler chickens.  

PubMed

To determine the efficiency of benzoic acid, a feeding experiment was carried out with 240 one-day old ROSS 308 cockerels. Birds were divided into three dietary treatments: I (C) - no additives, II (B1) - 0.1% inclusion of benzoic acid, III (B2) - the inclusion of 0.2% benzoic acid. The performance results were similar in birds fed the control diet and the diet with 0.1% of benzoic acid. The dietary inclusion of benzoic acid at 0.2% depressed the growth of broiler chickens (p < 0.05). The dry matter of the digesta increased in the crop and caeca after benzoic acid supplementation. The pH of the caecal contents decreased following benzoic acid supplementation and was the lowest in the B2 group. No differences were found in the pH of the crop, ileal, gizzard digesta and rectum content. Lactic acid bacteria populations were the lowest in the caeca of the B1 group (p < 0.05). Coliform bacteria decreased in the caeca contents following increased benzoic acid supplementation. PMID:19138347

Jzefiak, D; Kaczmarek, S; Rutkowski, A

2009-11-12

73

Benzoic acid transformation via conjugation with peptides and final fate of conjugates in higher plants  

Microsoft Academic Search

Transformation of [114C]- and [714C] benzoic acids in sterile seedlings of maize (Zea mays) and pea (Pisum sativum) was studied. The tested labeled compounds were supplied in plants through roots as water solutions. The larger part of the assimilated benzoic acid forms conjugates with low-molecular-weight plant peptides. As a result of hydrolytic cleavage of the conjugation products, initial labeled benzoic

D. Chrikishvili; T. Sadunishvili; G. Zaalishvili

2006-01-01

74

Pd-catalyzed decarboxylative arylation of thiazole, benzoxazole, and polyfluorobenzene with substituted benzoic acids.  

PubMed

A Pd-catalyzed decarboxylative coupling of thiazoles and benzoxazole with various substituted benzoic acids is developed. The reaction is compatible with both electron-rich and electron-poor benzoic acids. It can also be extended to the synthesis of polyfluoro-substituted biaryls using polyfluorobenzenes as the starting materials. PMID:20201587

Xie, Kai; Yang, Zhiyong; Zhou, Xingjian; Li, Xiujian; Wang, Sizhuo; Tan, Ze; An, Xiangyu; Guo, Can-Cheng

2010-04-01

75

Electron-impact ionization of benzoic acid, nicotinic acid and their n-butyl esters  

NASA Astrophysics Data System (ADS)

Electron-impact ionization mass spectra, the decay of metastable ions, ionization and appearance energies and bond energies, as dissociation energies, are reported for the title compounds. An ionization energy of 9.47 eV was obtained for benzoic acid, 9.43 eV for benzoic acid n-butyl ester, 9.61 eV for nicotinic acid and 9.97 eV for nicotinic acid n-butyl ester. Molecular ions of both butyl esters show two common main fragmentation pathways: the first process is a McLafferty rearrangement, characterized by the transfer of one H-atom from the aliphatic ester chain, which leads to the ions of either the organic acid or 1-butene. From their appearance energies and known thermodynamic data, gas-phase formation enthalpies () of the parent n-butyl esters are calculated. Values of for benzoic acid n-butyl ester and for nicotinic acid n-butyl ester were obtained. The second process is characterized by the transfer of two H-atoms from the ester chain leading to a protonated form of the corresponding organic acids and C4H7 radicals. Good evidence is provided for the formation of methylallyl radicals. Appearance energies are used to calculate a proton affinity (PA) for benzoic acid. The obtained value of PA = (8.73 0.3) eV, corresponding to a protonation of the carbonyl group, is in close corroboration with published data (PA = 8.51 eV). Activation energies for the intermediate H-transfers were found to be insignificant. This methodic gateway is applied to the system of nicotinic acid and its butyl ester. Adopting the formation of a methylallyl radical, the obtained proton affinity of nicotinic acid, PA = 8.58 eV, is very near to the published data of benzoic acid. An alternative fragmentation mechanism leading to a value of PA [approximate] 9.5 eV (typical for a protonation of the pyridine-nitrogen) is very unlikely. It is concluded that this transfer of two H-atoms from the ester chain is controlled by a charge switching between the carboxylic oxygen atoms which leads to a regiospecific protonation site, in this case to the protonated carbonyl group. This is conform with a B3LYP DFT calculation with a corresponding proton affinity of PA = 8.29 eV.

Opitz, Joachim

2007-08-01

76

Proteins induced in Escherichia coli by benzoic acid.  

PubMed Central

Proteins induced by benzoic acid in Escherichia coli were observed on two-dimensional electrophoretic gels (2-D gels). Cultures were grown in glucose-rich medium in the presence or absence of 20 mM benzoate at an external pH of 6.5, where the pH gradient (deltapH) is large and benzoate accumulates, and at an external pH of 8.0, where deltapH is inverted and little benzoate is taken up. Radiolabeled proteins were separated on 2-D gels and were identified on the basis of the index of VanBogelen and Neidhardt. In the absence of benzoic acid, little difference was seen between pH 6.5 and pH 8.0; this confirms that the mechanisms of protein homeostasis in this range are constitutive, including the transition between positive and inverted deltapH. Addition of benzoate at pH 6.5 increased the expression of 33 proteins. Twelve of the benzoate-induced proteins were induced at pH 8.0 as well, and nine of these matched proteins induced by the uncoupler dinitrophenol. Eighteen proteins were induced by benzoate only at pH 6.5, not at pH 8.0, and were not induced by dinitrophenol. One may be the iron and pH regulator Fur, which regulates acid tolerance in Salmonella spp. The other 13 proteins had not been identified previously. The proteins induced by benzoate only at a low pH may reflect responses to internal acidification or to accumulation of benzoate.

Lambert, L A; Abshire, K; Blankenhorn, D; Slonczewski, J L

1997-01-01

77

Particle engineering of benzoic acid by spherical agglomeration.  

PubMed

The influence of process conditions on the properties of benzoic acid spherical agglomerates, are investigated. Agglomerates are produced in a fed-batch agitated tank process. Benzoic acid is dissolved in ethanol and the solution is mixed with the bridging liquid, before being fed into an agitated aqueous solution. A broader investigation has been performed using heptane as the bridging liquid, and in further experiments different bridging liquids are compared. The results show that the bridging liquid has an influence on the product properties, with diethyl ether and ethyl acetate being at the extreme end with no agglomerates formed at all. Using any of the other five solvents (chloroform, toluene, heptane, pentane, or cyclohexane) spherical agglomerates are formed, as long as a sufficient amount of the bridging liquid is used. The results show that the particle size and strength increase with increasing amount of bridging liquid, and with decreasing temperature. At amount of bridging liquid producing optimum particle shape, the largest agglomerates are produced when using either cyclohexane operating at 5 C, or using toluene in a process at 20 C. The highest particle fracture stress is obtained using toluene as the bridging liquid regardless of temperature. The particle shape depends on the bridging liquid, and becomes completely spherical when toluene or pentane is used. For four of the solvents the particle morphology improves with decreasing temperature, but for cyclohexane the result is the opposite. By continued agitation beyond the completion of the feeding, particle size and strength gradually increases and also the shape gradually becomes more spherical. High compressibility and low elastic recovery suggest that the particles are favorable for direct tabletting. The results are analyzed and discussed against capillary theory and granulation mechanisms. PMID:22266212

Thati, Jyothi; Rasmuson, ke C

2012-01-15

78

Benzoic Acid Doping to Enhance Electromagnetic Properties of MgB2 Superconductors  

Microsoft Academic Search

The effect of benzoic acid doping on lattice parameters, microstructure, critical temperature (Tc), critical current density (Jc) and flux pinning force of MgB2 has been studied. In this work we used benzoic acid as an example of aromatic acids as an additive to MgB2. For different sintering process, actual carbon (C) substitution for boron (B) was estimated to be from

W. X. Li; Y.. Li; M. Y. Zhu; R. H. Chen; X.. Xu; W. K. Yeoh; J. H. Kim; S. X. Dou

2007-01-01

79

Synergistic extraction of europium(III) with benzoic acid and thenoyltrifluoroacetone  

SciTech Connect

The solvent extraction of europium(III) into solutions of thenoyltrifluoroacetone and benzoic acid in cyclohexane, carbon tetrachloride, benzene, chloroform, pentachloroethane, and tetrachloroethane has been measured at 25/sup 0/ C. It has been found that the extracted species involve two types of adducts, EuA/sub 3/HB and EuA/sub 3/ . 2HB where A denotes the TTA anion and HB the benzoic acid monomer. The magnitude of the adduct formation constants in different solvents has been correlated with the dimerization constants of benzoic acid in the solvents. 2 figures, 2 tables.

Hasegawa, Y.; Nakano, T.

1983-01-01

80

Selective adsorption of benzoic acid species on patterned OH/Si(100) surface  

SciTech Connect

It has recently been observed that benzoic acid strongly reacts with OH group on the silicon surface. Here, by defining the area in which OH group is adsorbed on the Si surface, the selective adsorption of benzoic acid species was attempted. The patterned OH/Si surface was prepared by irradiating the zeroth order beam from the bending magnet of the synchrotron facility through the gold mesh placed in front of the OH/Si sample. For discerning the selectively adsorbed molecule by x-ray photoelectron emission microscopy (X-PEEM) at N k edge, 4-nitrobenzoic acid was utilized instead of benzoic acid. Near edge x-ray absorption fine structure spectra at carbon and oxygen k edges were in good accord with the previous results obtained from the benzoic acid system. The X-PEEM images around N k edge clearly showed that the molecules adsorb only on the area in which OH groups remain.

Ihm, Kyuwook; Han, Jin Hee; Kim, Bongsoo; Chung, Sukmin; Hwang, Chan-Cuk; Kang, Tai-Hee; Kim, Ki-Jeong; Jung, Yu Jin; An, Ki-Seok [Department of Physics, POSTECH, Pohang, Kyungbuk 790-784 (Korea, Republic of) and Beamline Research Division, Pohang Accelerator Laboratory (PAL), Pohang, Kyungbuk 790-984 (Korea, Republic of); Beamline Research Division, Pohang Accelerator Laboratory (PAL), Pohang, Kyungbuk 790-784 (Korea, Republic of); Division of Molecular and Life Sciences, Department of Chemistry, Center for Integrated Molecular Systems, POSTECH, Pohang, Kyungbuk 790-784 (Korea, Republic of); Thin Film Materials Laboratory, Advanced Materials Division, Korea Research Institute of Chemical Technology, Daejeon 305-600 (Korea, Republic of)

2006-08-15

81

On the Flash Point of Benzoic AcidPart 2: Experimental Measurements  

Microsoft Academic Search

A previous paper in which it was shown that the widely accepted value for the flash point of benzoic acid cannot be correct was followed by some experimental tests on the compound with a flash point apparatus.

J. Godefroy; J. C. Jones; G. Fowler

2001-01-01

82

Optimized Dispersive LiquidLiquid Microextraction and Determination of Sorbic Acid and Benzoic Acid in Beverage Samples by Gas Chromatography  

Microsoft Academic Search

A new rapid method for direct determination of trace levels of sorbic and benzoic acids was developed by dispersive liquidliquid\\u000a microextraction and gas chromatography with flame ionization detection. In the proposed approach, the separation procedure\\u000a of sorbic and benzoic acids was performed on a general chromatographic column without any prior derivatization processes.\\u000a Some effective parameters on the microextraction recovery were

Taher Ahmadzadeh Kokya; Khalil Farhadi; Aram AliMohammad Kalhori

83

Time-dependent conversion of benzyl alcohol to benzaldehyde and benzoic acid in aqueous solutions  

Microsoft Academic Search

The oxidative reaction: benzyl alcoholbenzaldehydebenzoic acid was investigated in time in aqueous solutions of benzyl alcohol widely used as a preservative in medicine and cosmetology. The solutions of benzyl alcohol were stored at concentrations from 0.005 to 2.09mg\\/ml for a long time under different conditions. The presence of benzaldehyde and benzoic acid in these solutions was controlled by liquid chromatography

N. N. Sudareva; E. V. Chubarova

2006-01-01

84

Dissociation quotient of benzoic acid in aqueous sodium chloride media to 250C  

Microsoft Academic Search

The dissociation quotient of benzoic acid was determined potentiometrically in a concentration cell fitted with hydrogen electrodes. The hydrogen ion molality of benzoic acid\\/benzoate solutions was measured relative to a standard aqueous HCl solution at seven temperatures from 5 to 250C and at seven ionic strengths ranging from 0.1 to 5.0 molal (NaCl). The molal dissociation quotients and selected literature

Richard M. Kettler; David J. Wesolowski; Donald A. Palmer

1995-01-01

85

Adsorption of benzoic acid onto high specific area activated carbon cloth  

Microsoft Academic Search

The adsorption of benzoic acid from aqueous solution onto high area carbon cloth at different pH values has been studied. Over a period of 125 min the adsorption process was found to follow a first-order kinetics and the rate constants were determined for the adsorption of benzoic acid at pH 2.0, 3.7, 5.3, 9.1, and 11.0. The extents of adsorption

Erol Ayranci; Numan Hoda; Edip Bayram

2005-01-01

86

Ferrous iron oxidation by Thiobacillus ferrooxidans: inhibition with benzoic acid, sorbic acid and sodium lauryl sulfate  

SciTech Connect

Acid mine drainage is formed by the weathering or oxidation of pyritic material exposed during coal mining. The rate of pyritic material oxidation can be greatly accelerated by certain acidophilic bacteria such as Thiobacillus ferrooxidans which catalyse the oxidation of ferrous to ferric iron. A number of organic compounds, under laboratory conditions, can apparently inhibit both the oxidation of ferrous to ferric iron by T. ferrooxidans and the weathering of pyritic material by mixed cultures of acid mine drainage micro-organisms. Sodium lauryl sulphate (SLS), an anionic surfactant has proved effective in this respect. Benzoic acid, sorbic acid and SLS at low concentrations, each effectively inhibited bacterial oxidation of ferrous iron in batch cultures of T. ferrooxidans. The rate of chemical oxidation of ferrous iron in low pH, sterile, batch reactors was not substantially affected at the tested concentrations of any of the compounds.

Onysko, S.J.

1984-07-01

87

Benzoic acid inhibition of the alpha, beta, and gamma isozymes of Agaricus bisporus tyrosinase.  

PubMed

Inhibition of the catecholase and cresolase reactions of the alpha, beta, and gamma isozymes of Agaricus bisporus tyrosinase by benzoic acid was investigated at 25.0 and 8.0 degrees C at pH 5.60 in air-saturated solutions. Benzoic acid is a simple competitive inhibitor of the cresolase reaction of all three isozymes. In the catecholase reaction, however, benzoic acid is a partial uncompetitive inhibitor of the alpha and beta isozymes and a simple competitive inhibitor of gamma-tyrosinase. Equilibrium dialysis experiments, conducted under identical conditions to the kinetic studies, indicate that benzoic acid can bind to the alpha and gamma isozymes in the absence of organic substrate. The dissociation constants obtained by equilibrium dialysis are in good agreement with the kinetic Ki values determined from inhibition studies. Maximum binding of benzoic acid to alpha and gamma tyrosinase, however, is significantly less than one mole per mole of active sites. A scheme in which benzoic acid binds to the oxy-form of tyrosinase is proposed to account for the kinetic and equilibrium results. PMID:2112900

Menon, S; Fleck, R W; Yong, G; Strothkamp, K G

1990-07-01

88

Adsorption of benzoic acid from aqueous solution by three kinds of modified bentonites.  

PubMed

Benzoic acid removal is important for the water treatment, and adsorption is an efficient treatment process. Three kinds of modified bentonites, hydroxy-aluminum pillared bentonite (Al(OH)-Bent), octadecyl trimethyl ammonium chloride modified bentonite (OTMAC-Bent), and both octadecyl trimethyl ammonium chloride and hydroxy-aluminum modified bentonite (Al(OH)-OTMAC-Bent) were prepared and characterized by XRD, FTIR, and BET analysis. Experiments were conducted on the adsorption of benzoic acid by the prepared modified bentonites at different temperatures in batch experiments. The results show benzoic acid adsorption capabilities of Na-Bent and Al(OH)-Bent are even low, but high for OTMAC-Bent and Al(OH)-OTMAC-Bent. Optimal conditions for the adsorption of benzoic acid on OTMAC-Bent and Al(OH)-OTMAC-Bent were as follows: pH of 3.5, 0.04 g/mL adsorbent, and contact time of 90 min. Increased adsorption with temperature indicates that the adsorptions of benzoic acid onto Al(OH)-OTMAC-Bent and OTMAC-Bent are spontaneous and endothermic. The adsorption data could be well interpreted by the Langmuir model and Temkin Equation. The adsorption efficiency was higher than 85%, suggesting that OTMAC-Bent and Al(OH)-OTMAC-Bent are excellent adsorbents for effective benzoic acid removal from water. PMID:21543084

Xin, Xiaodong; Si, Wei; Yao, Zhenxing; Feng, Rui; Du, Bin; Yan, Liangguo; Wei, Qin

2011-04-18

89

Catalytic Ring Hydrogenation of Benzoic Acid with Supported Transition Metal Catalysts in scCO2  

PubMed Central

The ring hydrogenation of benzoic acid to cyclohexanecarboxylic acid over charcoal-supported transition metal catalysts in supercritical CO2 medium has been studied in the present work. The cyclohexanecarboxylic acid can be produced efficiently in supercritical CO2 at the low reaction temperature of 323 K. The presence of CO2 increases the reaction rate and several parameters have been discussed.

Wang, Hongjun; Zhao, Fengyu

2007-01-01

90

Ferrocene containing chelating ligands 3. Synthesis, spectroscopic characterization, electrochemical behaviour and interaction with metal ions of new ligands obtained by condensation of ferrocenecarboxaldehyde with 2-amino-benzoic acid derivatives. Crystal structures of 2-ferrocenylmethylamino-5-methyl-benzoic acid and 2-bis(ferrocenylmethyl)ammonium-5-methyl-benzoic acid perchlorate  

Microsoft Academic Search

Ferrocenecarboxaldehyde reacts with 2-amino-benzoic acid, 2-amino-5-methyl-benzoic acid or 3-amino-2-naphthoic acid to give the corresponding Schiff-base derivatives 2-ferrocenylmethylidenimino-benzoic acid (1), 2-ferrocenylmethylidenimino-5-methyl-benzoic acid (2) and 3-ferrocenylmethylidenimino-2-naphthoic acid (3). 1, 2 and 3 are stable in the solid state but easily hydrolyze in solution. This hydrolysis has been studied kinetically in a methanol-water medium. In order to increase the stability in solution to

Juan Cano; Angel Benito; Ramn Martnez-Mez; Juan Soto; Jordi Pay; Francesc Lloret; Miguel Julve; M. Dolores Marcos; Ekkehard Sinn

1995-01-01

91

Ferrous iron oxidation by Thiobacillus ferrooxidans: inhibition with benzoic acid, sorbic acid, and sodium lauryl sulfate  

SciTech Connect

Thiobacillus ferrooxidans promote indirect oxidation of pyrite through the catalysis of the oxidation of ferrous iron to ferric iron, which is an effective oxidant of pyrite. These bacteria also may catalyze direct oxidation of pyrite by oxygen. A number of organic compounds, under laboratory conditions, can apparently inhibit both the oxidation of ferrous iron to ferric iron by T. ferrooxidans and the weathering of pyritic material by mixed cultures of acid mine drainage microorganisms. In this study, benzoic acid, sorbic acid, and sodium lauryl sulfate at low concentrations (5 to 10 mg/liter) each effectively inhibited bacterial oxidation of ferrous iron in batch cultures of Thiobacillus ferrooxidans. The rate of chemical oxidation of ferrous iron in low-pH, sterile batch reactors was not substantially affected at the tested concentrations (5 to 50 mg/liter) of any of the compounds.

Onysko, S.J.; Kleinmann, R.L.P.; Erickson, P.M.

1984-07-01

92

Induction of functional cytochrome P450 and its involvement in degradation of benzoic acid by Phanerochaete chrysosporium.  

PubMed

The white rot fungus Phanerochaete chrysosporium has the largest cytochrome P450 contingent known to date in fungi, but the study on the function of these P450s is limited. In this study, induction of functional P450 in P. chrysosporium was first shown and P450-mediate degradation of benzoic acid was demonstrated in this fungus. Carbon monoxide difference spectra indicated significant induction of P450 by benzoic acid, m-chlorobenzoic acid, p-chlorobenzoic acid and n-hexane, and showed the effect of inducer concentration and nutrient condition on the induction of P450. The high contents of P450 in the microsomal fractions facilitated the study on the function of P450. While the n-hexane-induced P450 could not interact with benzoic acid, the microsomal P450 induced by benzoic acid produced type I substrate binding spectra upon the addition of benzoic acid. The benzoic acid degradation by the microsomal P450 was NADPH-dependent at a specific rate of 194 +/- 14 min(-1), and significantly inhibited by piperonyl butoxide (a P450 inhibitor). However, inhibition of benzoic acid degradation by piperonyl butoxide was slight or not detectable in the cultures of this fungus, suggesting presumable involvement of other enzyme in benzoic acid degradation. The extracellular ligninolytic enzymes, lignin peroxidase and manganese-dependent peroxidase, were not involved in initial metabolism of benzoic acid under the test conditions. PMID:19787435

Ning, Daliang; Wang, Hui; Zhuang, Yuan

2009-09-29

93

Effect of chlorophenoxyacetic acid herbicides on glycine conjugation of benzoic acid.  

PubMed

1. 2,4-Dichlorophenoxyacetic acid (2,4-D) and 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) (0.1-0.5 mmol/kg i.p.) delayed the disappearance of injected benzoate from blood and diminished the urinary excretion of the formed benzoylglycine, but elevated the blood levels of benzoylglycine in rat, suggesting that these herbicides interfere with both the formation and the renal transport of benzoylglycine. 2. Inhibition of the renal excretion of benzoylglycine by 2,4-D or 2,4,5-T (0.5 mmol/kg i.p.) was directly demonstrated in rat injected with benzoylglycine. 3. Inhibition of benzoylglycine formation from benzoic acid by 2,4-D or 2,4,5-T (0.5 mmol/kg i.p.) was directly demonstrated in renal pedicles-ligated rats injected with benzoate. 4. Neither 2,4-D nor 2,4,5-T influenced the hepatic concentrations of ATP, coenzyme A (CoA) or glycine; therefore, it is unlikely that they inhibit glycine conjugation of benzoic acid by diminishing the availability of co-substrates. 5. Although the chlorophenoxyacetic acids did not appear to be a substrate for the mitochondrial acyl-CoA synthetases, both 2,4-D and 2,4,5-T diminished the activity of benzoyl-CoA synthetase (but not that of benzoyl-CoA:glycine N-acyltransferase) in solubilized hepatic mitochondria. These findings suggest that 2,4-D and 2,4,5-T impair benzoylglycine formation in rat by inhibiting benzoyl-CoA synthetase. PMID:10426554

Gregus, Z; Halszi, E; Klaassen, C D

1999-06-01

94

High-Performance Liquid Chromatography Analysis and Assessment of Benzoic Acid in Yogurt, Ayran, and Cheese in Turkey  

Microsoft Academic Search

Among food sources, particular attention is paid to milk and dairy products, due to its nutritional importance. Benzoic acid\\u000a is extensively used in the preservation of foods. A reliable method for the determination of benzoic acid in some dairy products,\\u000a such as yogurt, ayran, and cheese using high-performance liquid chromatography and UV detection was validated. The peak of\\u000a benzoic acid

Aydin Yildiz; Sait Erdogan; Abdurrahman Saydut; Candan Hamamci

95

??????????????????????????????????????????????? ????????????? ?????????????????? ??? ?????????????? Determination of Benzoic Acid and Sorbic Acid in Bael Fruit, Rossella Drink and Flavor Concentrate Syrups by Steam Distillation. ????? ????????????* ?????? ??????????? 1  

Microsoft Academic Search

????????: ??????????????????????????????? ????????????? ????????? ?????????????????????? ?????????????? ????????????????????????? ?????????????????????????????? ???????????? ????????????????? ?????????? Platinum EPS C18 ??????????????? 0.01 ?????? pH 4.5 ??? ????????????????????????? ??????????? 1.0 ???????????????? ??????????????????????????????? 240???????? ???????????????????????????????????????????????????????????????????? ???? ??????????????????? 50-1000 ???????????????? ????????????? ??? 90-107% ??? 87-118% ????????? ????????????????????????????????????????????????????????? ??????????????????? ??????????? Abstract: Benzoic acid and sorbic acid in bael fruit, rossella drink and flavor concentrate syrups were extracted by steam distillation

Ladda Wattanasiritham; Kulvadee Trongpanich

96

Investigation of the process of incorporation of tritium into the molecules of halosubstituted benzoic acids, fatty acids, and prostaglandins  

Microsoft Academic Search

An investigation was made of the influence of various factors on the incorporation of tritium into the molecules of halosubstituted benzoic acids, fatty acids, prostaglandins, and their mixtures. It was established that the degrees of dehalogenation and hydrogenation of the compounds vary differently, depending on the conditions of the reaction with gaseous tritium. Thus, the possibility of obtaining labeled biologically

V. P. Shevchenko; V. V. Bezuglov; T. Yu. Lazurkina; A. V. Potapova; N. F. Myasoedov

1987-01-01

97

Sorbic and benzoic acid in non-preservative added food products in Turkey  

Microsoft Academic Search

Sorbic acid (SA) and benzoic acid (BA) were determined in yogurt, tomato and pepper paste, fruit juices, chocolates, soups and chips in Turkey by using High Pressure Liquid Chromatography (HPLC). Levels were compared with Turkish Food Codex limits. SA was only detected in 2 of 21 yogurt samples, contrary to BA, that was found in all yogurt samples but one,

Ruziye Cakir; Arzu Cagri-Mehmetoglu

2012-01-01

98

Effects of benzoic and cinnamic acids on membrane permeability of soybean roots  

Microsoft Academic Search

Benzoic (BEN) and cinnamic (CIN) acids are commonly found in soils and are considered as strong allelochemicals. Published information suggest that BEN and CIN and other phenolic acids decrease plant growth in part by suppressing nutrient absorption. However, studies on the mechanism of action were not conclusive. We examined the effects of BEN and CIN on the cell plasma membrane

R. Baziramakenga; G. D. Leroux; R. R. Simard

1995-01-01

99

Formation of phenol under conditions of the reaction of oxidative carbonylation of benzene to benzoic acid  

SciTech Connect

This paper describes conditions for the oxidation of benzene to phenol. It is shown that a reaction mixture of water, carbon monoxide, and oxygen are essential to the oxidation. The oxidation is a side reaction found to occur during the oxidative carbonylation of benzene to benzoic acid in a medium of trifluoroacetic acid.

Kalinovsky, I.O.; Leshcheva, A.N.; Pogorelov, V.V.; Gelbshtein, A.I.

1993-12-31

100

A More Challenging Interpretative Nitration Experiment Employing Substituted Benzoic Acids and Acetanilides  

ERIC Educational Resources Information Center

|An experiment is described involving the nitration of ortho or meta monosubstituted benzoic acids (XC[subscript 6]H[subscript 4]CO[subscript 2]H, X = Halogen, Me, OH, or OMe) and monochlorinated acetanilides with nitric acid to determine the regioselectivity of addition by [superscript 1]H NMR spectroscopy and molecular modeling. Students were

Treadwell, Edward M.; Lin, Tung-Yin

2008-01-01

101

A limited LCA of bio-adipic acid: Manufacturing the nylon-6,6 precursor adipic acid using the benzoic acid degradation pathway from different feedstocks  

Microsoft Academic Search

A limited life cycle assessment (LCA) was performed on a combined biological and chemical process for the production of adipic acid, which was compared to the traditional petrochemical process. The LCA comprises the biological conversion of the aromatic feedstocks benzoic acid, impure aromatics, toluene, or phenol from lignin to cis, cis-muconic acid, which is subsequently converted to adipic acid through

Duuren van J. B. J. H; B. Brehmer; A. E. Mars; G. Eggink; V. A. P. Martins dos Santos; J. P. M. Sanders

2011-01-01

102

Modeling molecular acidity with electronic properties and Hammett constants for substituted benzoic acids.  

PubMed

Molecular acidity is an important physiochemical property essential in many fields of molecular studies, but an efficient and reliable computational approach to make accurate predictions is still missing. In this work, based on our previous studies to use gas phase electronic properties such as molecular electrostatic potential and valence natural atomic orbitals of the acidic atom and leaving proton, we demonstrate here that different approaches can be employed to tackle this problem. To that end, we employ 196 singly, doubly, and triply substituted benzoic acids for the study. We show that two different approaches are possible, one focusing on the carboxyl group through its localized electronic properties and the other on the substituting groups via Hammett constants and their additivity rule. Our present results clearly exhibit that with the linear models built from the singly substituted species, one can accurately predict the pK(a) values for the doubly and triply substituted species with both of these two approaches. The predictions from these approaches are consistent with each other and agree well with the experimental data. These intrinsically different approaches are the two manifestations of the same molecular acidity property, both valid and complementary to each other. PMID:22082252

Huang, Ying; Liu, Lianghong; Liu, Wanhui; Liu, Shaogang; Liu, Shubin

2011-12-02

103

Genetic engineering to contain the Vitreoscilla hemoglobin gene enhances degradation of benzoic acid by Xanthomonas maltophilia  

SciTech Connect

Xanthomonas maltophilia was transformed with the gene encoding Vitreoscilla (bacterial) hemoglobin, vgb, and the growth of the engineered strain was compared with that of the untransformed strain using benzoic acid as the sole carbon source. In general, growth of the engineered strain was greater than that of the untransformed strain; this was true for experiments using both overnight cultures and log phase cells as inocula, but particularly for the latter. In both cases the engineered strain was also more efficiency than the untransformed strain in converting benzoic acid into biomass.

Liu, S.C.; Webster, D.A.; Wei, M.L.; Stark, B.C. [Illinois Inst. of Technology, Chicago, IL (United States)

1996-01-05

104

Augmenting the activity of antifungal agents against aspergilli using structural analogues of benzoic acid as chemosensitizing agents  

Microsoft Academic Search

A number of benzoic acid analogues showed antifungal activity against strains of Aspergillus flavus, Aspergillus fumigatus and Aspergillus terreus, causative agents of human aspergillosis, in in vitro bioassays. Structureactivity analysis revealed that antifungal activities of benzoic and gallic acids were increased by addition of a methyl, methoxyl or chloro group at position 4 of the aromatic ring, or by esterification

Jong H. Kim; Bruce C. Campbell; Noreen Mahoney; Kathleen L. Chan; Russell J. Molyneux; Arunmozhi Balajee

2010-01-01

105

Augmenting the activity of antifungal agents against aspergilli using structural analogues of benzoic acid as chemosensitizing agents  

Technology Transfer Automated Retrieval System (TEKTRAN)

Several benzoic acid analogs showed antifungal activity against strains of Aspergillus flavus, A. fumigatus and A. terreus, causative agents of human aspergillosis. Structure-activity analysis revealed that antifungal activities of benzoic and gallic acids increased by addition of a methyl, methoxyl...

106

Biologically active metabolites from fungi, 19: new isocoumarins and highly substituted benzoic acids from the endophytic fungus, Scytalidium sp.  

PubMed

Six known metabolites, two new isocoumarins 4 and 8, and one new highly substituted benzoic acid derivative 9 were isolated from the ethyl acetate culture extract of a fungal endophyte, Scytalidium sp. In addition, another new benzoic acid 10 with an unusual 1,2-dicarbonyl side chain was indirectly identified from its methylated derivatives 10a-10d. PMID:15143840

Krohn, Karsten; Sohrab, Md Hossain; Aust, Hans-Jrgen; Draeger, Siegfried; Schulz, Barbara

2004-06-01

107

Variability of olfactory receptor neuron responses of female silkmoths ( Bombyx mori L.) to benzoic acid and ()-linalool  

Microsoft Academic Search

Of the two sensory neurons present in each sensillum trichodeum on antennae of female silk-moths, Bombyx mori, one was activated by stimulation with benzoic acid (benzoic acid cell), the other with ()-linalool (terpene cell). Using single-cell recordings we studied the temporal characteristics of the nerve impulse response of both cell types. The time course of the impulse response was shown

Thomas Heinbockel; Karl-Ernst Kaissling

1996-01-01

108

OPTICAL DEPHASiNG IN A CLA8!GLIKE SYSTEM: A PHOTON ECHO STUDY OF PENTACENE IN BENZOIC ACID  

Microsoft Academic Search

Optical absorption and picosecond photon echo evpenments are used to study the dephasing of pentacene in benzoic acid. It IS shown that, while the absorption spectrum of pentacene is effected by proton transfer in the benzoic acid dimer, the dephasng IS caused by elastic and loelastx phonon scatter& processes.

Koos DUPPEN; Laurens W. MOLENKAMP; Jos B. W. MORSINK; Douwe A. WIERSMA

109

40 CFR 721.1725 - Benzoic acid, 3,3-methyl-enebis [6 amino-, di-2-propenyl ester.  

Code of Federal Regulations, 2010 CFR

...Chemical Substances § 721.1725 Benzoic acid, 3,3-methyl-enebis...this section: 61386-02-5, Benzoic acid, 3,3-methylenebis [6 amino...intends to manufacture, import, or process the chemical substance...

2010-07-01

110

40 CFR 721.1725 - Benzoic acid, 3,3-methyl-enebis [6 amino-, di-2-propenyl ester.  

Code of Federal Regulations, 2010 CFR

...Chemical Substances § 721.1725 Benzoic acid, 3,3-methyl-enebis...this section: 61386-02-5, Benzoic acid, 3,3-methylenebis [6 amino...intends to manufacture, import, or process the chemical substance...

2009-07-01

111

2-(2-Methyl-benzo-yl)benzoic acid: catemeric hydrogen bonding in a ?-keto acid.  

PubMed

The crystal structure of the title compound, C15H12O3, displays catemeric aggregation involving O-H?O hydrogen bonds progressing from the carboxyl group of one mol-ecule to the ketone O atom of another glide-related neighbor. The mol-ecule is twisted, with the toluene 80.61?(3) out of plane with respect to the phenyl group of the benzoic acid. The acid group makes a dihedral angle of 13.79?(14) with the attached phenyl ring. The mol-ecules are achiral, but the space group glide planes create alternating conformational chirality in the chain units. The four hydrogen-bonding chains progress along [001] in an A-A-B-B pattern (right-to-left versus left-to-right), and are related to each other by the center of symmetry at (0.5, 0.5, 0.5) in the chosen cell. There is one close contact (2.54?) between a phenyl H atom and the acid carbonyl from a symmetry-related mol-ecule. PMID:24098232

Platosz, Natalia A; Lalancette, Roger A; Thompson, Hugh W; Newman, Jacob M; Schachter, Ari

2013-09-18

112

RETINOIDAL BENZOIC ACIDS (AROTENOIDS) AND OTHER RETINOIDS INHIBIT IN VITRO TRANSFORMATION OF EPITHELIAL CELLS  

EPA Science Inventory

Five retinoids were calcluated for their ability to inhibit N-methyl-N'nitro-N-nitrosoguanidine (MNNG)-induccd transformation of primary rat trachcal epithelial (RTE) cells in culture at concentrations that did not affect cell survival. wo retinoidal benzoic acids (arotcnoids), R...

113

40 CFR 721.1728 - Benzoic acid, 2-(3-phenylbutylidene)amino-, methyl ester.  

Code of Federal Regulations, 2013 CFR

(1) The chemical substance identified as benzoic acid, 2-(3-phenylbutylidene)amino-, methyl ester (PMN P-85-1211) is subject to reporting under this section for the significant new uses described in paragraph (a)(2) of this section. (2) The significant new uses...

2013-07-01

114

40 CFR 721.1728 - Benzoic acid, 2-(3-phenylbutylidene)amino-, methyl ester.  

Code of Federal Regulations, 2010 CFR

(1) The chemical substance identified as benzoic acid, 2-(3-phenylbutylidene)amino-, methyl ester (PMN P-85-1211) is subject to reporting under this section for the significant new uses described in paragraph (a)(2) of this section. (2) The significant new uses...

2010-07-01

115

40 CFR 721.10380 - Benzoic acid, 3-amino-2-mercapto-.  

Code of Federal Regulations, 2013 CFR

(1) The chemical substance identified as benzoic acid, 3-amino-2-mercapto- (PMN P-10-285; CAS No. 71807-60-8) is subject to reporting under this section for the significant new uses described in paragraph (a)(2) of this section. (2) The significant new uses are: (i) Release to...

2013-07-01

116

Correlation between chemical structure and rodent repellency of benzoic acid derivatives  

USGS Publications Warehouse

Sixty-five benzoic acid derivatives were either prepared or obtained from commercial concerns, tested for rat repellency, and their indices of repellency computed. The data from these tests were considered analytically for any correlation between chemical structure and rat repellency. The results suggest a qualitative relationship which is useful in deciding probability of repellency in other compounds.

Fearn, J.E.; DeWitt, J.B.

1965-01-01

117

Deuteration of pentacene in benzoic acid: Monitoring the reaction kinetics via low-temperature optical spectroscopy  

SciTech Connect

In the deuteration of pentacene in benzoic acid, this reaction is monitored via low-temperature optical spectroscopy to observe the proton-deuterium rate of exchange between the solvent and solute molecules. Of the 14 pentacene protons, 6 have an exchange rate 2 orders of magnitude greater than the remaining 8. 20 refs., 3 figs.

Corval, A.; Casalegno, R.; Astilean, S.; Trommsdorff, H.P. [Universite Joseph Fourier, Grenoble (France)

1992-06-25

118

Calculation of vapor pressure curves for hydroxy benzoic acid derivatives using thermogravimetry  

Microsoft Academic Search

This study aims at providing a simple thermogravimetric method in estimating the vapor pressure characteristics using the Antoine equation as the analytical tool. The heat treatment for the majority of benzoic acid derivatives follows zero order rate processes that are in good correlation with their evaporation process. The optimum conditions for the rising temperature experiments were found when the heating

Koustuv Chatterjee; David Dollimore; Kenneth S Alexander

2002-01-01

119

Solar photocatalytic thin film cascade reactor for treatment of benzoic acid containing wastewater  

Microsoft Academic Search

A solar photocatalytic cascade reactor was constructed to study the photocatalytic oxidation of benzoic acid in water under various experimental and weather conditions at HKUST. Nine stainless steel plates coated with TiO2 catalyst were arranged in a cascade configuration in the reactor. Photolytic degradation and adsorption were confirmed to be insignificant total organic carbon (TOC) removal mechanisms. A turbulent flow

Alex H. C. Chan; Chak K. Chan; John P. Barford; John F. Porter

2003-01-01

120

Adsorption of Benzoic Acid on Synthetic Calcite Dispersed in Cyclohexane as a Function of Temperature  

Microsoft Academic Search

The adsorption of benzoic acid on synthetic calcite dispersed in cyclohexane has been studied between 296 and 346 K. The results can be successfully explained by a two-step model involving a Langmuir adsorption of first a layer of molecules oriented parallel to the surface and next, as the concentration of the adsorbate in the liquid phase increases, a gradual replacement

Lene Madsen; Christian Grn; Ida Lind; John Engell

1998-01-01

121

Investigation of the process of incorporation of tritium into the molecules of halosubstituted benzoic acids, fatty acids, and prostaglandins  

SciTech Connect

An investigation was made of the influence of various factors on the incorporation of tritium into the molecules of halosubstituted benzoic acids, fatty acids, prostaglandins, and their mixtures. It was established that the degrees of dehalogenation and hydrogenation of the compounds vary differently, depending on the conditions of the reaction with gaseous tritium. Thus, the possibility of obtaining labeled biologically active compounds by selective dehalogenation or selective hydrogenation of the corresponding precursors was demonstrated.

Shevchenko, V.P.; Bezuglov, V.V.; Lazurkina, T.Yu.; Potapova, A.V.; Myasoedov, N.F.

1987-01-01

122

Catalytic hydroxylation of benzoic acid by hydrogen peroxide  

SciTech Connect

An effective catalytic system based on Fe(III) and surfactants is proposed for the hydroxylation of benozic acid by hydrogen peroxide in an aqueous medium at a temperature of 30-80{degrees}C. 8 refs., 1 tab.

Pulippurasseril, C.R.; Filippova, T.Yu.; Dedov, A.G. [M.V. Lomonosov Moscow State Univ. (Russian Federation)

1992-12-31

123

Radiometric and voltammetric study of benzoic acid adsorption on a polycrystalline silver electrode  

Microsoft Academic Search

Adsorption of benzoic acid was studied on polycrystalline silver electrodes in a 0.1M perchloric acid solution. The electrodes were obtained by electroplating of Ag-black onto a vacuum-deposited silver substrate. The real surface area of such prepared electrodes was calculated from a total capacitance of the electric double layer, determined from the plot of the voltammetric double-layer charging current as a

Piotr Waszczuk; Piotr Zelenay; Jerzy Sobkowski

1998-01-01

124

The roles of benzoic acid and water on the Michael reactions of pentanal and nitrostyrene catalyzed by diarylprolinol silyl ether.  

PubMed

The roles of benzoic acid and water on the Michael reaction of pentanal and nitrostyrene catalyzed by diarylprolinol silyl ether are revealed by density functional theory calculations. The calculations demonstrate that the benzoic acid is ready to attack the catalysts and form a hydrogen bond between the hydrogen atom of the COOH of benzoic acid and one of the N atoms of the catalyst. The complex formed from pentanal, catalyst and benzoic acid attacks nitroalkene and forms transition states. Finally, the transition states hydrolyze and the products are formed. The calculations demonstrate that the stereoselectivity is dominated by the steric hindrance of the 2-substituent groups, and the benzoic acid can increase the reaction rate evidently by decreasing the activation energies; however, H(3)O(+) or strong acid may prevent the formation of the transition states between enamines and nitroalkenes. The employed solvent can decrease the activation energies and promote the proton transfer from benzoic acid onto the catalyst 2. The calculated enantiomeric excess values are in good agreement with the experimental results. These calculations also reveal that the role of benzoic acid is dependent on the sophisticated structures of the catalysts and provide a valuable index for the structural design of new catalysts and selection of additives or co-catalysts. PMID:22806075

Zhou, Jin; Chang, Qing; Gan, Li-Hua; Peng, Yun-Gui

2012-07-18

125

Photocatalyzed degradation on a TiO 2-coated quartz crystal microbalance. Adsorption\\/desorption processes in real time in the degradation of benzoic acid and salicylic acid  

Microsoft Academic Search

The photocatalytic degradations of benzoic acid, phenol and salicylic acid were examined subsequent to in situ adsorption\\/desorption of the organic substrates on a TiO2-coated quartz crystal microbalance (QCM). The amount of substrate adsorbed from the bulk aqueous solution on the TiO2-coated QCM sensor was investigated at different pH under dark conditions. The order of adsorption was salicylic acid>phenol?benzoic acid on

Hisao Hidaka; Haruo Honjo; Satoshi Horikoshi; Nick Serpone

2006-01-01

126

Structure-activity relationship study on benzoic acid part of diphenylamine-based retinoids.  

PubMed

Based on structure-activity relationship studies of the benzoic acid part of diphenylamine-based retinoids, the potent RXR agonist 4 was derivatized to obtain retinoid agonists, synergists, and an antagonist. Cinnamic acid derivatives 5 and phenylpropionic acid derivatives 6 showed retinoid agonistic and synergistic activities, respectively. The difference of the activities is considered to be due to differences in the flexibility of the carboxylic acid-containing substituent on the diphenylamine skeleton. Compound 7, bearing a methyl group at the meta position to the carboxyl group, was an antagonist, dose-dependently inhibiting HL-60 cell differentiation induced by 3.3 10(-10)M Am80. PMID:23217961

Ohta, Kiminori; Kawachi, Emiko; Shudo, Koichi; Kagechika, Hiroyuki

2012-11-15

127

Structure of complexes of germanium tetrachloride with isomeric amino benzoic acids and their derivatives  

Microsoft Academic Search

benzoic acid (GeC14 ?9 40AB), GeC14 ?9 6 0-aminobenzoic acid (GeC14 ?9 60AB), GeC14 . 4 m-aminobenzoic acid (GeC14 ?9 4 MAB), GeC14 ?9 4 p-aminobenzoic acid (GeC14 ?9 4 PAB), and oeC14 ?9 4 anesthesin* (GeC14 . 4 ANS). Their individuality was confirmed by x-ray diffraction, and several properties were determined [10]. The indicated compounds hydrolyzed in water and

E. M. Belousova; I. I. Seifullina; V. N. Reznichenko

1970-01-01

128

Simultaneous determination of gallic acid, albiflorin, paeoniflorin, ferulic acid and benzoic acid in SiWu decoction by high-performance liquid chromatography DAD method  

Microsoft Academic Search

A high-performance liquid chromatographic method was applied to the determination of gallic acid, albiflorin, paeoniflorin, ferulic acid and benzoic acid in SiWu decoction and other 13 combinations of the formula. These five compounds were analyzed simultaneously with a Zorbox SB C-18 column by gradient elution using 0.01% (v\\/v) phosphoric acidacetonitrile as the mobile phase. The flow rate was 1mlmin?1, and

Yu-Xin Sheng; Lie Li; Qiao Wang; Hong-Zhu Guo; De-An Guo

2005-01-01

129

Benzoic acid, a stimulant of odorant receptors of Bombyx mori, is rapidly metabolized to N-benzoylserine on the antennae  

Microsoft Academic Search

Summary. Benzoic acid is a known stimulant of olfactory receptor cells in trichoid sensilla on the antennae of adult females of Bombyx mori. Exposure of freshly excised antennae, from B. mori females and males, to vapours of [14C]-benzoic acid revealed that the adsorbed acid is rapidly metabolized (15% conversion in 10 s), suggesting the presence of\\u000a a highly active enzymatic

Corina Oldenburg; Sudha Kanaujia; Dieter Spiteller; Neil J. Oldham; Wilhelm Boland; Karl-Ernst Kaissling

2001-01-01

130

Optical and structural properties of annealed PE:LiNbO3 waveguides formed with pyrophosphoric and benzoic acids  

Microsoft Academic Search

The optical and structural properties of protonated lithium niobate waveguides have been investigated. The proton-exchange process was performed by immersing Z-cut substrates in molten pyrophosphoric and benzoic acids at 240 C for 8 h. Surface refractive index changes of 0.148 (pyrophosphoric acid) and 0.124 (benzoic acid) were obtained at ?=632.8 nm. The exchanged samples were subjected to annealing for 1

C. Ziling; L. Pokrovskii; N. Terpugov; I. Savatinova; M. Kuneva; S. Tonchev; M. N. Armenise; V. M. N. Passaro

1993-01-01

131

A new protein conformation indicator based on biarsenical fluorescein with an extended benzoic acid moiety.  

PubMed

We demonstrate herein a new protein conformation indicator based on biarsenical fluorescein with an extended benzoic acid moiety. The present indicator is reactive to a genetically introduced tetracysteine motif (Cys-Cys-Xaa-Xaa-Cys-Cys, where Xaa is a noncysteine amino acid) of proteins. Compared to the original biarsenical fluorescein (FlAsH) and the biarsenical Nile red analogue (BArNile), the present indicator exhibited larger fluorescence intensity changes in response to Ca(2+)-induced conformational rearrangements of calmodulin. A calculation of the highest occupied molecular orbital (HOMO) level of the benzoic acid moiety of the indicator molecule supports possible involvement of a photoinduced electron transfer (PET) process. These results indicate that the present indicator is useful for sensitive detection of protein conformational changes. PMID:15055950

Nakanishi, Jun; Maeda, Mizuo; Umezawa, Yoshio

2004-02-01

132

Structure-based inhibitors of influenza virus sialidase. A benzoic acid lead with novel interaction.  

PubMed

Influenza virus sialidase is a surface enzyme that is essential for infection of the virus. The catalytic site is highly conserved among all known influenza variants, suggesting that this protein is a suitable target for drug intervention. The most potent known inhibitors are analogs of 2-deoxy-2,3-didehydro-N-acetylneuraminic acid (Neu5Ac2en), particularly the 4-guanidino derivative (4-guanidino-Neu5Ac2en). We utilized the benzene ring of 4-(N-acetylamino)benzoic acids as a cyclic template to substitute for the dihydropyran ring of Neu5Ac2en. In this study several 3-(N-acylamino) derivatives were prepared as potential replacements for the glycerol side chain of Neu5Ac2en, and some were found to interact with the same binding subsite of sialidase. Of greater significance was the observation that the 3-guanidinobenzoic acid derivative (equivalent to the 4-guanidino grouping of 4-guanidino-Neu5Ac2en), the most potent benzoic acid inhibitor of influenza sialidase thus far identified (IC50 = 10 microM), occupied the glycerol-binding subsite on sialidase as opposed to the guanidino-binding subsite. This benzoic acid derivative thus provides a new compound that interacts in a novel manner with the catalytic site of influenza sialidase. PMID:7650674

Singh, S; Jedrzejas, M J; Air, G M; Luo, M; Laver, W G; Brouillette, W J

1995-08-18

133

One-pot synthesis of benzoic acid by electrocatalytic reduction of bromobenzene in the presence of CO 2  

Microsoft Academic Search

The electrocatalytic properties of Ag for the reduction of organic halides have been exploited for one-pot electrosynthesis of benzoic acid. Among various investigated dipolar aprotic solvents, only dimethylformamide gives good results. The process has been investigated both under potentiostatic and galvanostatic control. In both cases, the reaction smoothly proceeds under mild conditions and lasts in a few hours, giving benzoic

Abdirisak A. Isse; Christian Durante; Armando Gennaro

2011-01-01

134

A chromene and prenylated benzoic acid from Piper aduncum  

Microsoft Academic Search

In addition to nerolidol, 2?,6?-dihydroxy-4?-methoxydihydrochalcone, methyl 2,2-dimethyl-8-(3?-methyl-2?-butenyl)-2H-1-chromene-6-carboxylate, methyl 2,2-dimethyl-2H-1-chromene-6-carboxylate and methyl 8-hydroxy-2,2-dimethyl-2H-1-chromene-6-carboxylate, two new natural products were isolated from the leaves of Piperaduncum, 2,2-dimethyl-2H-1-chromene-6-carboxylic acid and 3-(3?,7?-dimethyl-2?,6?-octadienyl)-4-methoxybenzoic acid. The structures of the isolates were established based on analysis of spectroscopic data, including ESMS. The DNA-damaging activity of the isolated compounds was also investigated against mutant strains of Saccharomyces cerevisiae.

Debora Cristina Baldoqui; Massuo Jorge Kato; Alberto Jos Cavalheiro; Vanderlan da Silva Bolzani; Maria Claudia M. Young; Maysa Furlan

1999-01-01

135

Tyrosinase inhibitory effect of benzoic acid derivatives and their structure-activity relationships.  

PubMed

A series of benzoic acid derivatives 1-10 have been synthesised by two different methods. Compounds 1-6 were synthesised by a facile procedure for esterification using N,N'-dicyclohexylcarbodiimide (DCC) as a coupling agent, methylene chloride as a solvent system and dimethylaminopyridine (DMAP). While 7-10 were synthesised by converting benzoic acid into benzoyl chloride by treating with thionyl chloride in the presence of benzene and performing a further reaction with amine in dried benzene. The structures of all the synthesised derivatives of benzoic acid (1-10) were assigned on the basis of extensive NMR studies. All of them showed inhibitory potential against tyrosinase. Among them, compound 7 was found to be the most potent (1.09 ?M) when compared with the standard tyrosinase inhibitors of kojic acid (16.67 ?M) and L-mimosine (3.68 ?M). Finally in this paper, we have discussed the structure-activity relationships of the synthesised molecules. PMID:20476840

Khan, Sher Bahadar; Hassan Khan, Mahmud Tareq; Jang, Eui Sung; Akhtar, Kalsoom; Seo, Jongchul; Han, Haksoo

2010-05-17

136

Synthesis of 5-nitro-2-(N-3-(4-azidophenyl)-propylamino)-benzoic acid: Photoaffinity labeling of human red blood cell ghosts with a 5-nitro-2-(3-phenylpropylamino)-benzoic acid analog  

Microsoft Academic Search

A photoaffinity analog of the potent epithelial chloride channel blocker 5-nitro-2-(3-phenylpropylamino)-benzoic acid has been synthesized and characterized. In the dark, this reagent, 5-nitro-2-(N-3-(4-azidophenyl)-propylamino)-benzoic acid, and the parent compound reversibly inhibited chloride efflux in human red blood cell ghosts. Irradiation of ghost membranes with 350 microM arylazide analog reduced the rate of chloride efflux to 33% of the control value. The

B. R. Branchini; M. H. Murtiashaw; L. A. Egan

1991-01-01

137

Influence of alternative electron acceptors on the anaerobic biodegradability of chlorinated phenols and benzoic acids  

SciTech Connect

Methanogeneic conditions can promote the biodegradation of a number of halogenated aromatic compounds. This study, using sediments from freshwater and estuarine sites, is an evaluation of the anaerobic biodegradability of monochlorinated phenols and benzoic acids coupled to denitrification, sulfidogenesis, and methanogenesis. The results indicate that chlorinated phenols and benzoic acids are biodegradable under at least one set of anaerobic conditions. Metabolism depends both on the electron acceptor available and on the position of the chlorine substituent. Presence of alternative electron acceptors, nitrate, sulfate, and carbonate, can affect degradation rates and substrate specificities. Since contaminated sites usually have mixtures of wastes, bioremediation efforts may need to consider the activities of diverse anaerobic communities to carry out effective treatment of all components. 37 refs., 4 figs., 4 tabs.

Haeggblom, M.M.; Rivera, M.D.; Young, L.Y. (New York Medical Center, NY (United States))

1993-04-01

138

Simultaneous determination of preservatives (benzoic acid, sorbic acid, methylparaben and propylparaben) in foodstuffs using high-performance liquid chromatography  

Microsoft Academic Search

A reversed-phased HPLC method that allows the separation and simultaneous determination of the preservatives benzoic (BA) and sorbic acids (SA), methyl- (MP) and propylparabens (PP) is described. The separations were effected by using an initial mobile phase of methanolacetate buffer (pH 4.4) (35:65) to elute BA, SA and MP and changing the mobile phase composition to methanolacetate buffer (pH 4.4)

Bahruddin Saad; Muhammad Idiris Saleh; Kamarudzaman Ahmad; Mohd. Khairuddin Mohd. Talib

2005-01-01

139

ESR study of the photochemistry of benzoic acid derivatives  

SciTech Connect

Electron spin resonance (ESR) has been used to study radical intermediates in the photochemistry of a number of aromatic carboxylic acids, esters, anhydrides, amides, imides, and nitriles. Continuous photolysis was used to produce the radicals in either aqueous or alcoholic media. The triplet states of the compounds undergo two reactions in the presence of a hydrogen donor such as 2-propanol. A hydrogen atom is transferred to certain carbon atoms of the aromatic ring forming cyclohexadienyl radicals. In most cases, addition occurs at or opposite the carboxyl (or cyano) group. The pattern of addition is attributed to the higher spin density in the triplet at those positions. This pattern also correlates with the positions of higher hyperfine splitting in the corresponding anion radicals. In a parallel reaction, a hydrogen atom is also transferred to an oxygen of the carboxyl group (for acids, anhydrides, and esters) to form the one-electron-reduction product. The cyclohexadienyl radicals are not formed by protonation on a carbon of an anion radical. The ESR spectra of most of the cyclohexadienyl radicals are highly polarized to the extent that the low-field lines appear in emission. This effect is believed to be normal chemically induced dynamic spin polarization (CIDEP) as a result of cross reactions with the other radicals present. 46 refs., 7 figs., 10 tabs.

Jeevarajan, A.S.; Fessenden, R.W. (Univ. of Notre Dame, IN (United States))

1992-12-16

140

Aneroid Bomb Calorimeter for Determining the Heat of Combustion of Thermochemical Standard Benzoic Acid  

Microsoft Academic Search

An electrically calibrated bomb calorimeter is described which has no stirred water, and is mounted in an evacuated outer jacket. Its departures from the ideal are investigated. The heat of combustion of samples from a batch of specially pure benzoic acid is found to be 26431\\\\cdot7 J\\/g under `standard bomb conditions', with an estimated standard error of 2.2 J\\/g. This

A. R. Meetham; J. A. Nicholls

1960-01-01

141

Histometric Assessment of the Age-Related Skin Response to 2Hydroxy5Octanoyl Benzoic Acid  

Microsoft Academic Search

Only a handful of topical products have been shown to limit or improve age-related skin damage. 2-Hydroxy-5-octanoyl benzoic acid, also designated ?-lipohydroxyacid (?-LHA), is among the active molecules claiming such effects. The present randomized placebo-controlled double-blind study was undertaken to evaluate the effects of ?-LHA in young and older women. Both groups responded to the ?-LHA-containing formulation, although to different

Mabel Avila-Camacho; Christiane Montastier; Grald E. Pirard

1998-01-01

142

Electrochemical reactions of benzoic acid on platinum and palladium studied by DEMS. Comparison with benzyl alcohol  

Microsoft Academic Search

The electrochemical reactivity of benzoic acid on porous platinum and palladium electrodes has been studied by cyclic voltammetry and differential electrochemical mass spectrometry (DEMS) in aqueous 0.1 M HClO4. The objective of this work is to investigate the adsorption processes and the reactivity of this compound on different noble metals, in order to compare these results with those obtained for

Ricardo M Souto; Jos L Rodr??guez; Luis Fernndez-Mrida; Elena Pastor

2000-01-01

143

Kinetic study of adsorption and degradation of aniline, benzoic acid, phenol, and diuron in soil suspensions  

Microsoft Academic Search

Laboratory studies were conducted to investigate the effects of low temperature and accelerated soil-solution contact on soil adsorption of labile organic chemicals. The authors measured the kinetics of adsorption and degradation of ¹⁴C-aniline, ¹⁴C-benzoic acid, ¹⁴C-phenol, and ¹⁴C-diuron in the solution phase at 3 and 22°C. In the initial stages of reactions, the adsorption of all four chemicals was instantaneous

T. H. Dao; T. L. Lavy

1987-01-01

144

Proton tunneling in benzoic acid crystals at intermediate temperatures: Nuclear magnetic resonance and neutron scattering studies  

Microsoft Academic Search

The dynamics of proton transfer along the hydrogen bonds of dimers of benzoic acid has been characterized in single crystals and powders at temperatures between 10 K and 110 K by quasi-elastic neutron scattering (QENS) and by proton spin-lattice relaxation using field-cycling NMR spectroscopy. These measurements define the geometry of the proton transfer, the energy difference between the two tautomers

M. Neumann; D. F. Brougham; C. J. McGloin; M. R. Johnson; A. J. Horsewill; H. P. Trommsdorff

1998-01-01

145

Deuteriation of benzoic acid in the presence of homogeneous potassium tetrachloroplatinate(II) catalyst  

Microsoft Academic Search

The kinetic behavior of deuteriation of benzoic acid with D2O acidified with HCl in the presence of homogeneous K2PtCl4 catalyst has been investigated in the 100130C temperature interval. The quasiunimolecular H\\/D rate constants at 100 and 130C corresponding to an exchange process in ortho positions of the substituted benzene ring hydrogens were determined by1H NMR integration signal. These same constants

M. Ka?ska; R. Ka?ski

1992-01-01

146

The catalytic oxidation of benzoic acid to phenol in high temperature water  

Microsoft Academic Search

The oxidation of benzoic acid (BA) to phenol (the Dow Phenol Process) has been studied in high temperature water (HTW) using a continuous flow system over various metal oxide heterogeneous catalysts: NiO, CuO, Carulite, MnO2 and Al2O3. Excellent selectivities (>99%) and good yields for phenol (up to 70%) were obtained. The reaction conditions were optimised by varying the temperature, the

Joan Fraga-Dubreuil; Juan Garcia-Serna; Eduardo Garcia-Verdugo; Lucinda M. Dudd; Graham R. Aird; W. Barry Thomas; Martyn Poliakoff

2006-01-01

147

Effect of water on the kinetics of the catalytic reaction between benzoic acid and aniline  

Microsoft Academic Search

Water forming in benzanilide synthesis from benzoic acid and aniline catalyzed by titanium tetrabutoxide does not influence\\u000a the activity of the catalyst. The role of mass transfer processes associated with water removal from the system is revealed.\\u000a The reversible deactivation of titanium tetrabutoxide by water occurs in the absence of vigorous water boiling and distillation.\\u000a The stability of titanium tetrabutoxide

L. Ya. Shteinberg; S. A. Kondratov; S. M. Shein; V. V. Marshalova

2007-01-01

148

Characterization of a benzoic acid modified glassy carbon electrode expressed quantitatively by new statistical parameters  

Microsoft Academic Search

The main aim of this study is to characterize the nanosurface of the benzoic acid modified glassy carbon (GC) electrode by using a new statistical approach. In this study, the electrode surfaces were modified by cyclic voltametry in the potential range of +0.4 and ?0.8V at a scan rate 200mVs?1 for four cycles versus Ag\\/Ag+ electrode in acetonitrile containing 0.1M

Raoul R. Nigmatullin; Dumitru Baleanu; Erdal Din; Ali Osman Solak

2009-01-01

149

Modeling of diffusive transport of benzoic acid through a liquid membrane  

Microsoft Academic Search

A model of diffusive transport of benzoic acid through a liquid membrane (LM) separating two aqueous solutions, based on diffusion\\u000a layers and the assumption of a steady state, has been developed and tested using experimental results. It has been found that\\u000a a model with the apparent partition coefficient dependent on the concentration is able to describe the time dependence of

Stanis?aw Koter; Piotr Szczepa?ski

150

Macro kinetic studies for photocatalytic degradation of benzoic acid in immobilized systems  

Microsoft Academic Search

Semiconductor photocatalytic process has been studied extensively in recent years due to its intriguing advantages in environmental remediation. In this study, a two-phase swirl-flow monolithic-type reactor is used to study the kinetics of photocatalytic degradation of benzoic acid in immobilized systems. Transport contributions into the observed degradation rates were determined when catalyst is immobilized. Intrinsic kinetic rate constants and its

Kanheya Mehrotra; Gregory S. Yablonsky; Ajay K. Ray

2005-01-01

151

Size and morphology of benzoic acid crystals produced by drowning-out crystallisation  

Microsoft Academic Search

Benzoic acid is crystallised from saturated ethanolwater solutions by adding water or an ethanolwater mixture in semi-batch experiments. The influence of precipitant addition rate, ethanol concentration in the bulk solution and ethanol concentration in the feed, have been studied. The product particles are characterised by microscopic determination of the projected area diameter and the aspect ratio. It is found that

X Holmbck; . C Rasmuson

1999-01-01

152

Removal of benzoic acid in aqueous solution by Fe(III) homogeneous photocatalysis  

Microsoft Academic Search

The behaviour of the system Fe(III)\\/Air\\/UVbenzoic acid is investigated in the pH range 2.05.5 and Fe(III) concentration up to 60?M. The oxidation process develops through the establishment of an iron cycle in which HO radicals are produced by Fe(OH)2+ photolysis and the resulting Fe(II) photo-oxidized to Fe(III) by dissolved oxygen. A kinetic model is developed and used to simulate the

Roberto Andreozzi; Raffaele Marotta

2004-01-01

153

Adsorption of benzoic acid from aqueous solution by three kinds of modified bentonites  

Microsoft Academic Search

Benzoic acid removal is important for the water treatment, and adsorption is an efficient treatment process. Three kinds of modified bentonites, hydroxy-aluminum pillared bentonite (Al(OH)-Bent), octadecyl trimethyl ammonium chloride modified bentonite (OTMAC-Bent), and both octadecyl trimethyl ammonium chloride and hydroxy-aluminum modified bentonite (Al(OH)-OTMAC-Bent) were prepared and characterized by XRD, FTIR, and BET analysis. Experiments were conducted on the adsorption of

Xiaodong Xin; Wei Si; Zhenxing Yao; Rui Feng; Bin Du; Liangguo Yan; Qin Wei

2011-01-01

154

Dietary exposure of secondary school students in Hong Kong to benzoic acid in prepackaged non-alcoholic beverages  

Microsoft Academic Search

This study evaluated the dietary exposure of secondary school students in Hong Kong to benzoic acid from pre-packaged non-alcoholic beverages. Exposure was estimated using local food consumption data of secondary school students obtained by a semi-quantitative food frequency questionnaire in 2000 and the benzoic acid level detected in pre-packaged beverages, including soft drink (both diet\\/light and regular types), fruit juice,

Ka Ming Ma; Cheok Man Chan; Stephen Wai Cheung Chung; Yuk Yin Ho; Ying Xiao

2009-01-01

155

A note on effect of benzoic acid supplementation on the performance and microbiota population of broiler chickens  

Microsoft Academic Search

In order to determine the efficiency of benzoic acid, a feeding experiment was carried out on 400 one-day-old Cobb 500 cockerels. The birds were divided into four dietary treatments: control without additives, or with 2.5, 5 and 7.5 g of benzoic acid per kg diet, respectively. Performance was similar in birds fed the control diet and that with 2.5 g

D. Jzefiak; S. Kaczmarek; M. Bochenek; A. Rutkowski

156

Design of a composite amperometric enzyme electrode for the control of the benzoic acid content in food  

Microsoft Academic Search

A graphiteTeflontyrosinase composite biosensor for the determination of benzoic acid in foodstuffs is reported. The biosensor functioning is based on the inhibition effect of benzoic acid on the biocatalytic activity of the enzyme in a reversed micelle working medium formed with ethyl acetate as the continuous phase, a 0.05 moll?1 phosphate buffer solution of pH 7.4 (5%) as the aqueous

M. D Morales; S Morante; A Escarpa; M. C Gonzlez; A. J Reviejo; J. M Pingarrn

2002-01-01

157

TAC101, a benzoic acid derivative, inhibits liver metastasis of human gastrointestinal cancer and prolongs the life-span  

Microsoft Academic Search

We examined the anti-tumor effect of a novel benzoic acid derivative, TAC-101 (4-[3,5-bis(trimethylsilyl) benzamide] benzoic acid) on models with liver metastasis. Oral administration of TAC-101 significantly inhibited spontaneous liver metastasis of AZ-521 (human gastric cancer ) by orthotopic implan-tation to athymic nude mice. It also inhibited both the liver metastasis of AZ-521 induced by intrasplenic injection and the secondary lung

Koji Murakami; Konstanty Wierzba; Masaki Sano; Jiro Shibata; Kazuhiko Yonekura; Akihiro Hashimoto; Koji Sato; Yuji Yamada

1998-01-01

158

Selective extraction of benzoic acid from landfill leachate by solid-phase extraction and ion-exchange chromatography  

Microsoft Academic Search

In this work a simple method was described for selective extraction of benzoic acid from landfill leachate samples. The samples were submitted to solid-phase extraction (SPE) with XAD-4 resin as the stationary phase and ion-exchange chromatography (IEC) using the ion-exchange resin Amberlyst A-27. The instrumental analysis was performed by gas chromatography with mass spectrometric detection (GCMSD). Benzoic acid was isolated,

Iraj do Nascimento Filho; Patricia Schossler; Lisiane Santos Freitas; Maria Ins S Melecchi; Maria Goreti Rodrigues Vale; Elina Bastos Caramo

2004-01-01

159

Anaerobic decomposition of benzoic acid during methane fermentation: Specific activity of fatty acid intermediates and postion of radioactive label  

SciTech Connect

A study of the pathway of anaerobic decomposition of benzoic acid by a mixed methanogenic culture of bacteria was conducted. Specific activities of the possible fatty acid intermediates cyclohexanecarboxylic acid, propanoic acid, and acetic acid were determined. In the case of propanoic acid, the position of the radioactive label was also determined by isotropic trapping and Phares-Schmidt degradation of the intermediate. The specific activities of cyclohexanecarboxylic acid and propanoic acid are the same as the benzoate substrate fed to the mixed methanogenic cultures. These fatty acids must be direct breakdown products from the aromatic ring. When (4{minus}{sup 14}C) benzoate is the substrate, the propanoic acid produced is labeled exclusively in the carboxyl position. This supports the pathway proposed by Keith et al. (1978), but would be unlikely for the pathway proposed by Evans (1977). The specific activity of the acetic acid isolated from a culture fed (4{minus}{sup 14}C) benzoate is 42% of the specific activity of the substrate. This is possible only if the methylmalonyl-CoA pathway for the conversion of propanoate to acetate is not being utilized. The amount of various intermediates found indicates that at least three syntrophically linked organisms are present in the mixed methanogenic culture. One is responsible for the production of cyclohexanecarboxylic acid, one for the production of acetate from propanoate, and one for the production of methane.

Bridges, R.L.

1990-01-01

160

Dicarboxylic acids, ketocarboxylic acids, ?-dicarbonyls, fatty acids, and benzoic acid in urban aerosols collected during the 2006 Campaign of Air Quality Research in Beijing (CAREBeijing-2006)  

NASA Astrophysics Data System (ADS)

Ground-based studies of PM2.5 were conducted for determination of 30 water-soluble organic species, including dicarboxylic acids, ketocarboxylic acids and dicarbonyls, nine fatty acids, and benzoic acid, during the Campaign of Air Quality Research in Beijing 2006 (CAREBeijing-2006; 21 August to 4 September 2006) at urban (Peking University, PKU) and suburban (Yufa) sites of Beijing. Molecular distributions of dicarboxylic acids demonstrated that oxalic acid (C2) was the most abundant species, followed by phthalic acid (Ph) and succinic acid (C4) at both sites. The sum of three dicarboxylic acids accounted for 71% and 74% of total quantified water-soluble organics (327-1552 and 329-1124 ng m-3) in PKU and Yufa, respectively. Positive correlation was found between total quantified water-soluble species and water-soluble organic compounds (WSOC). On a carbon basis, total quantified dicarboxylic acids and ketocarboxylic acids and dicarbonyls account for up to 14.2% and 30.4% of the WSOC in PKU and Yufa, respectively, suggesting that they are the major WSOC fractions in Beijing. The distributions of fatty acids are characterized by a strong even carbon number predominance with maximum at hexadecanoic acid (C16:0). The ratio of octadecanoic acid (C18:0) to hexadecanoic acid (C16:0) (0.39-0.85, with an average of 0.36) suggests that in addition to vehicular emissions, an input from cooking emissions is important, as is biogenic emission. Benzoic acid that has been proposed as a primary pollutant from vehicular exhaust and a secondary product from photochemical reactions was found to be abundant: 72.2 58.1 ng m-3 in PKU and 78.0 47.3 ng m-3 in Yufa. According to the 72 hour back trajectory analysis, when the air mass passed over the southern or southeastern part of Beijing (24-25 August and 1-2 September), the highest concentrations of organic compounds were observed. On the contrary, when the clean air masses came straight from the north during 3-4 September, the lowest levels of organic compounds were recorded. This study demonstrates that pollution episodes in Beijing were strongly controlled by wind direction; that is, air quality in Beijing is good when air masses originate from the north and northwest, whereas it deteriorates when the air mass originates from the south and southeast.

Ho, K. F.; Lee, S. C.; Ho, Steven Sai Hang; Kawamura, Kimitaka; Tachibana, Eri; Cheng, Y.; Zhu, Tong

2010-10-01

161

The contribution of solvent drag to the intestinal absorption of the acidic drugs benzoic acid and salicylic acid from the jejunum of the rat  

Microsoft Academic Search

1.Jejunal loops of anaesthetized rats were perfused with hypotonic, isotonic and hypertonic buffered solutions containing 14C-labelled benzoic acid and salicylic acid at pH 6.2 and 2.2. The blood flow of the loop was maintained at an intermediate rate (0.780.97 ml min-1 g-1). The water net flux was determined by polyethylene glycol as non-absorbable marker and amounted up to +31 or-27

H. Ochsenfahrt; D. Winne

1974-01-01

162

ATR-FTIR characterization of transport properties of benzoic acid ion-pairs in silicone membranes.  

PubMed

A novel technique based on Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) spectroscopy was used to study the transport of benzoic acid ion-pairs/salts in silicone membranes. The benzoic acid ion-pairs were prepared using various counter-ions with different degrees of lipophilicity, e.g. triethylamine (TA), diethylamine (DE), tert-butylamine (t-BA), 2-amino-2-methyl-propanol (AMP), and 2-amino-2-methyl-propanediol (AMPD). Silicone membrane, treated or untreated with propylene glycol (PG), was placed on the surface of a ZnSe crystal and the transport solution was applied to the upper surface of the membrane. A mathematical model, based on Fick's second law describing the build up of permeant concentration at the membrane/crystal interface with time was applied to determine diffusion coefficients. Absorption due to the acid (1700 cm(-1)) or benzoate anion (1555 cm(-1)) was observed at different regions without the interference from PG or silicone membrane. Benzoate anion, a charged species, was observed to permeate the membrane. The permeation of benzoate anion from sodium benzoate and polar ion-pairs of AMP and AMPD was very low in contrast to their high-saturated concentrations in PG as compared to the t-BA ion-pair. This indicated that benzoate anion preferentially permeates the membrane as an ion-pair rather than a single anion; otherwise its permeation should correspond to its concentration in PG instead of the lipophilicity of the ion-pairs. Additionally, the diffusion coefficient values of benzoic acid and benzoate anions through the treated and untreated membranes were not statistically different. PMID:15363507

Tantishaiyakul, Vimon; Phadoongsombut, Narubodee; Wongpuwarak, Wibul; Thungtiwachgul, Jatupit; Faroongsarng, Damrongsak; Wiwattanawongsa, Kamonthip; Rojanasakul, Yon

2004-09-28

163

Electron-impact ionization of benzoic acid, nicotinic acid and their n-butyl esters: An approach to regioselective proton affinities derived from ionization and appearance energy data  

Microsoft Academic Search

Electron-impact ionization mass spectra, the decay of metastable ions, ionization and appearance energies and bond energies, as dissociation energies, are reported for the title compounds. An ionization energy of 9.47eV was obtained for benzoic acid, 9.43eV for benzoic acid n-butyl ester, 9.61eV for nicotinic acid and 9.97eV for nicotinic acid n-butyl ester.Molecular ions of both butyl esters show two common

Joachim Opitz

2007-01-01

164

Participation of a medium chain acyl-CoA synthetase in glycine conjugation of the benzoic acid derivatives with the electron-donating groups  

Microsoft Academic Search

Glycine conjugation of a series of benzoic acid derivatives was investigated in bovine liver mitochondria. Benzoic acids with chlorine, methyl, methoxy, or ethoxy substituents in the para- or metapositions of the benzene ring showed a high degree of glycine conjugation. In contrast, the acids with cyano, nitro, amino, or acetylamino groups were conjugated to a small extent with glycine. A

Fumiyo Kasuya; Kazuo Igarashi; Miyoshi Fukui

1996-01-01

165

Ultrafast formation of the benzoic acid triplet upon ultraviolet photolysis and its sequential photodissociation in solution  

SciTech Connect

Time-resolved infrared (TR-IR) absorption spectroscopy in both the femtosecond and nanosecond time domain has been applied to examine the photolysis of benzoic acid in acetonitrile solution following either 267 nm or 193 nm excitation. By combining the ultrafast and nanosecond TR-IR measurements, both the excited states and the photofragments have been detected and key mechanistic insights were obtained. We show that the solvent interaction modifies the excited state relaxation pathways and thus the population dynamics, leading to different photolysis behavior in solution from that observed in the gas phase. Vibrational energy transfer to solvents dissipates excitation energy efficiently, suppressing the photodissociation and depopulating the excited S{sub 2} or S{sub 3} state molecules to the lowest T{sub 1} state with a rate of {approx}2.5 ps after a delayed onset of {approx}3.7 ps. Photolysis of benzoic acid using 267 nm excitation is dominated by the formation of the T{sub 1} excited state and no photofragments could be detected. The results from TR-IR experiments using higher energy of 193 nm indicate that photodissociation proceeds more rapidly than the vibrational energy transfer to solvents and C-C bond fission becomes the dominant relaxation pathway in these experiments as featured by the prominent observation of the COOH photofragments and negligible yield of the T{sub 1} excited state. The measured ultrafast formation of T{sub 1} excited state supports the existence of the surface intersections of S{sub 2}/S{sub 1}, S{sub 2}/T{sub 2}, and S{sub 1}/T{sub 1}/T{sub 2}, and the large T{sub 1} quantum yield of {approx}0.65 indicates the importance of the excited state depopulation to triplet manifold as the key factor affecting the photophysical and photochemical behavior of the monomeric benzoic acid.

Yang Chunfan; Su Hongmei [Beijing National Laboratory for Molecular Sciences (BNLMS), State Key Laboratory of Molecular Reaction Dynamics, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); Sun Xuezhong; George, Michael W. [School of Chemistry, University of Nottingham, University Park NG7 2RD (United Kingdom)

2012-05-28

166

Molecular structures of benzoic acid and 2-hydroxybenzoic acid, obtained by gas-phase electron diffraction and theoretical calculations.  

PubMed

The structures of benzoic acid (C6H5COOH) and 2-hydroxybenzoic acid (C6H4OHCOOH) have been determined in the gas phase by electron diffraction using results from quantum chemical calculations to inform restraints used on the structural parameters. Theoretical methods (HF and MP2/6-311+G(d,p)) predict two conformers for benzoic acid, one which is 25.0 kJ mol(-1) (MP2) lower in energy than the other. In the low-energy form, the carboxyl group is coplanar with the phenyl ring and the O-H group eclipses the C=O bond. Theoretical calculations (HF and MP2/6-311+G(d,p)) carried out for 2-hydroxybenzoic acid gave evidence for seven stable conformers but one low-energy form (11.7 kJ mol(-1) lower in energy (MP2)) which again has the carboxyl group coplanar with the phenyl ring, the O-H of the carboxyl group eclipsing the C=O bond and the C=O of the carboxyl group oriented toward the O-H group of the phenyl ring. The effects of internal hydrogen bonding in 2-hydroxybenzoic acid can be clearly observed by comparison of pertinent structural parameters between the two compounds. These differences for 2-hydroxybenzoic acid include a shorter exocyclic C-C bond, a lengthening of the ring C-C bond between the substituents, and a shortening of the carboxylic single C-O bond. PMID:16836466

Aarset, Kirsten; Page, Elizabeth M; Rice, David A

2006-07-20

167

Adsorption of benzoic acid on [alpha]-alumina and [gamma]-boehmite  

SciTech Connect

The adsorption of benzoic acid (BzCOOH) on [alpha]-alumina ([alpha]-Al[sub 2]O[sub 3]) and [gamma]-boehmite ([gamma]-AlOOH) from the aqueous phase has been studied. The adsorption experiments were carried out in 0 and 0.1 M NaCl solutions, with pH adjusted to 4 or 6. For both [alpha]-alumina and [gamma]-boehmite, increasing ionic strength decreases the maximum adsorption. Increasing the pH to 6 at the same ionic strength also reduces the maximum adsorption markedly. This suggests that both the anion and the corresponding acid participate in the adsorption process. The results show that benzoic acid has a greater affinity for [alpha]-alumina than for [gamma]-boehmite. Under the same experimental conditions (0.1 M NaCl, pH 4) the maximum adsorption capacities are 5.0 and 1.5 [mu]mol/m[sup 2] for [alpha]-alumina and [gamma]-boehmite, respectively. This difference in adsorption capacities is probably due to the mineralogical difference. These results illustrate the importance of knowing the mineralogical composition of the solid phase.

Madsen, L. (Technical Univ. of Denmark, Lyngby (Denmark). Dept. of Geology and Geotechnical Engineering); Blokhus, A.M. (Univ. of Bergen (Norway). Dept. of Chemistry)

1994-08-01

168

Induction of benzoic acid 2-hydroxylase in virus-inoculated tobacco  

SciTech Connect

Salicylic acid (SA) plays an important role in the induction of plant resistance to pathogens. An accompanying article shows that SA is synthesized via the decarboxylation of cinnamic acid to benzoic acid (BA), which is, in turn, hydroxylated to SA. Leaf extracts of tobacco catalyze the 2-hydroxylation of Ba to SA. The monooxygenase catalyzing this reaction, benzoic acid 2-hydroxylase (BA2H), required NAD(P)H or reduced methyl viologen as an electron donor. BA2H activity was detected in healthy tobacco leaf extracts (1-2 nmol h[sup [minus]1] g[sup [minus]1] fresh weight) and was significantly increased upon inoculation with tobacco mosaic virus (TMV). This increase paralleled the levels of free SA in the leaves. Induction of BA2H activity was restricted to tissue expressing a hypersensitive response at 24[degrees]C. TMV induction of BA2H activity and Sa accumulation were inhibited when inoculated tobacco plants were incubated for 4 d at 32[degrees]C and then transferred to 24[degrees]C, they showed a 15-fold increase in BA2H activity and a 65-fold increase in free SA content compared with healthy plants incubated at 24[degrees]C. Treatment of leaf tissue with the protein synthesis inhibitor cycloheximide blocked the induction of BA2H activity by TMV. The effect of TMV inoculation on BA2H could be duplicated by infiltrating leaf discs of healthy plants with BA. This response was observed even when applied levels of BA were much lower than the levels observed in vivo after virus inoculation. Feeding tobacco leaves with phenylalanine, cinnamic acid, or o-coumaric acid (putative precursors of SA) failed to trigger the induction of BA2H activity. BA2H appears to be a pathogen-inducible protein with an important regulatory role in SA accumulation during the development of induced resistance to TMV in tobacco. 33 refs., 6 figs., 3 tabs.

Leon, J.; Yalpani, N.; Raskin, I.; Lawton, M.A. (Rutgers Univ., New Brunswick, NJ (United States))

1993-10-01

169

Adsorption of benzoic acid on [alpha]-alumina and [gamma]-boehmite  

Microsoft Academic Search

The adsorption of benzoic acid (BzCOOH) on [alpha]-alumina ([alpha]-Al[sub 2]O[sub 3]) and [gamma]-boehmite ([gamma]-AlOOH) from the aqueous phase has been studied. The adsorption experiments were carried out in 0 and 0.1 M NaCl solutions, with pH adjusted to 4 or 6. For both [alpha]-alumina and [gamma]-boehmite, increasing ionic strength decreases the maximum adsorption. Increasing the pH to 6 at the

L. Madsen; A. M. Blokhus

1994-01-01

170

DO-stat fed-batch production of cis, cis-muconic acid from benzoic acid by Pseudomonas putida BM014  

Microsoft Academic Search

For the production of cis,cis-muconic acid via biocatalytic conversion reactions from a toxic cosubstrate, benzoic acid, we developed a fed-batch process using computer-controlled DO-stat feeding. The mutant strain of Pseudomonas putida BM014 produced cis,cis-muconic acid with high conversion yield. More than 32 g\\/l of cis,cis-muconic acid was accumulated in 40 h including the initial batch and constant-feeding periods and a

Sang-Gu Bang; Cha Yong Choi

1995-01-01

171

Time-dependent density functional theory assessment of UV absorption of benzoic acid derivatives.  

PubMed

Benzoic acid (BA) derivatives of environmental relevance exhibit various photophysical and photochemical characteristics. Here, time-dependent density functional theory (TDDFT) is used to calculate photoexcitations of eight selected BAs and the results are compared with UV spectra determined experimentally. High-level gas-phase EOM-CCSD calculations and experimental aqueous-phase spectra were used as the references for the gas-phase and aqueous-phase TDDFT results, respectively. A cluster-continuum model was used in the aqueous-phase calculations. Among the 15 exchange-correlation (XC) functionals assessed, five functionals, including the meta-GGA hybrid M06-2X, double hybrid B2PLYPD, and range-separated functionals CAM-B3LYP, ?B97XD, and LC-?PBE, were found to be in excellent agreement with the EOM-CCSD gas-phase calculations. These functionals furnished excitation energies consistent with the pH dependence of the experimental spectra with a standard deviation (STDEV) of ?0.20 eV. A molecular orbital analysis revealed a ??* feature of the low-lying transitions of the BAs. The CAM-B3LYP functional showed the best overall performance and therefore shows promise for TDDFT calculations of processes involving photoexcitations of benzoic acid derivatives. PMID:23134517

Guo, Hao-Bo; He, Feng; Gu, Baohua; Liang, Liyuan; Smith, Jeremy C

2012-11-20

172

2-Amino-benzoic acid-4-(pyridin-4-yl-disulfan-yl)pyridine (1/1)  

PubMed Central

The title 1:1 co-crystal, C7H7NO2C10H8N2S2, features a highly twisted 4-(pyridin-4-yldisulfanyl)pyridine molecule [dihedral angle between the pyridine rings = 89.06?(10)]. A small twist is evident in the 2-aminobenzoic acid molecule, with the CCCO torsion angle being ?7.7?(3). An NH?O hydrogen bond occurs in the 2-aminobenzoic acid molecule. In the crystal, molecules are linked by OH?N and NH?N hydrogen bonds into a supramolecular chain along the b axis. These are connected into layers by ?? interactions occurring between pyridine rings [centroidcentroid distance = 3.8489?(15)?]. The layers are connected along the a axis by CH?O contacts. The crystal studied was a racemic twin.

Arman, Hadi D.; Kaulgud, Trupta; Tiekink, Edward R. T.

2011-01-01

173

Free and Conjugated Benzoic Acid in Tobacco Plants and Cell Cultures. Induced Accumulation upon Elicitation of Defense Responses and Role as Salicylic Acid Precursors  

Microsoft Academic Search

Salicylic acid (SA) is a key endogenous component of local and systemic disease resistance in plants. In this study, we investigated the role of benzoic acid (BA) as precursor of SA biosynthesis in tobacco (Nicotiana tabacum cv Samsun NN) plants undergoing a hypersensitive response following infection with tobacco mosaic virus or in tobacco cell suspensions elicited with b-megaspermin, an elicitor

Julie Chong; Marie-Agnes Pierrel; Rossitza Atanassova; Daniele Werck-Reichhart; Bernard Fritig; Patrick Saindrenan

2001-01-01

174

5-Nitro-2-(3-phenylpropylamino)benzoic acid is a GPR35 agonist.  

PubMed

GPR35 is a Gi/o- and G16-coupled receptor abundantly expressed in gastrointestinal tissues and immune cells. Kynurenic acid (a tryptophan metabolite and ionotropic glutamate receptor antagonist) and zaprinast (a phosphodiesterase inhibitor) are GPR35 agonists. Here, we show that the chloride channel blocker 5-nitro-2-(3-phenylpropylamino) benzoic acid (NPPB) is also a GPR35 agonist. NPPB activates the GPR35-Gi/o and GPR35-G16 pathways in human embryonic kidney 293 (HEK293) cells and induces intracellular calcium mobilization in a concentration-dependent manner in HEK293 cells coexpressing human, rat or mouse GPR35 and the chimeric G protein G(qi5). These results suggest a novel pharmacological activity of NPPB and will provide useful information to search for more potent and selective GPR35 agonists. PMID:18818509

Taniguchi, Yasuhito; Tonai-Kachi, Hiroko; Shinjo, Katsuhiro

2008-09-26

175

Preparation and physical properties of chitosan benzoic acid derivatives using a phosphoryl mixed anhydride system.  

PubMed

Direct benzoylation of the two hydroxyl groups on chitosan was achieved using a phosphoryl mixed anhydride system, derived from trifluoroacetic anhydride (TFAA), benzoic acids (BAs), and phosphoric acid (PA). The reaction is operated as a one pot process under mild conditions that does not require neither an inert atmosphere nor dry solvents. The structures of the synthesized compounds were confirmed by NMR and IR spectroscopy. Solubility tests on the products revealed that they were soluble in organic solvents such as N,N-dimethylformamide (DMF), dimethylsulfoxide (DMSO), and acetone. In the meantime, a morphological study by scanning electron microscopy (SEM) evidently indicated that the chitosan benzoates underwent significant structural changes after the benzoylation. PMID:22357319

Lee, Duckhee; Quan, Zhe Shan; Lu, Chichong; Jeong, Jin Ah; Song, Changhyun; Song, Mi-Sun; Chai, Kyu Yun

2012-02-22

176

3,5-Bis[(pyridin-4-yl)meth-oxy]benzoic acid  

PubMed Central

Single crystals of the title compound, C19H16N2O4, were obtained under hydrothermal conditions by an unintended recrystallization of the employed microcrystalline starting material. The [(pyridin-4-yl)methoxy]benzoic acid unit is nearly planar, with a maximum deviation from the least-squares plane of 0.194?(2)?. This plane is inclined by 35.82?(6) to that defined by the second (pyridin-4-yl)methoxy group [in which the largest deviation from the least-squares plane is 0.013?(2)?]. In the crystal, molecules are linked by OH?N hydrogen bonds involving the acid hydroxy group and a pyridine N atom into chains parallel to [-201].

Lin, Hong; Zhang, Yi-Ping

2013-01-01

177

[Effect of some non-steroidal antiinflammatory drugs and isomeric dihydroxy benzoic acids on the AAPH initiated degradation of crocin].  

PubMed

The authors examined the possible peroxyl radical scavanger effect of some non-steroidal antiinflammatory drugs and isomeric dihidroxy benzoic acids by means of the test based on 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH)-initiated degradation of crocin. The method is based on spectrophotometric determination of crocin, of which rate of AAPH-initiated degradation can be decreased in the presence of antioxidants with peroxyl radical scavanger activity. The authors studied the crocin degradation-inhibitory effect of phenacetin, paracetamol (acetaminophen), indomethacin, ibuprofen, diclofenac sodium, salicylic acid, salicylamide as well as the 2,3-, 2,4-, 2,5- and 3,4-dihydroxy substituted benzoic acids in 200 microM concentration. In the 60 minute studies the 2,3-, 2,5- and 3,4-dihydroxy benzoic acids proved to show the most effective degradation inhibitory effect. The results draw attention to the different antioxidant activity of salicylic acid and its hydroxylated metabolites (2,3- and 2,5-dihydroxy benzoic acids) formed under physiological conditions. PMID:17094661

Fodor, Krisztina; Lhman, Adrienn; Perjsi, Pl

2006-01-01

178

Thermodynamics of ionization processes for fluoro-substituted benzoic acids in waterdimethylformamide mixtures at 298.15 K  

Microsoft Academic Search

The ionization enthalpies, ?H0, of benzoic acid, o- and p-fluorobenzoic acids were measured calorimetrically at 298.15K in waterdimethylformamide (DMF) mixtures ranging from pure water up to 0.7 weight-fraction DMF. The ionization Gibbs energies, ?G0, of the acids in the same solutions were measured by the conductance method. The corresponding entropies, ?S0, of ionization were calculated. The effect of solvent and

Yan-Qing Nan; Qing-Sen Yu; Rui-Sen Lin

1998-01-01

179

Identification of bisprenylated benzoic acid derivatives from yerba santa (Eriodictyon ssp.) using sensory-guided fractionation.  

PubMed

Due to certain off-flavor problems and lacking bitter masking effects with Yerba Santa (Eriodictyon angustifolium and E. californicum) extracts, which are also described as bitter, herbal, medicinal, phenolic, or astringent, methanolic extracts were fractionated and evaluated for their taste properties using a high temperature liquid chromatography (HTLC)-based approach. The taste-guided fractionation led to the identification of a series of novel bisprenylated benzoic acids (erionic acids A (1), B (2), C (3), D (4), E (5), and F (6) and eriolic acids A (7), B (8), C (9), and D (10), respectively), along with the known flavonoids eriodictyol, homoeriodictyol, hesperetin, and chrysoeriol. The new compounds were isolated in larger amounts for characterization from Narrow Leaf Yerba Santa (E. angustifolium) and California Yerba Santa (E. californicum), respectively, using fast centrifugal partition chromatography (FCPC) and HTLC. The structures were elucidated using one and two-dimensional NMR spectroscopy and high resolution mass spectrometry (HR-MS). For E. californicum, data regarding seasonal and climatic variation of the eriolic acid contents and of the flavonoids were collected. The flavor properties of some of the isolated new compounds were evaluated; they showed strong off-flavor characteristics, such as bitter, astringent, phenolic, or woody, and may contribute to the sensory effects observed for crude Yerba Santa extracts. Erionic acid C (3) was not only able to increase the absolute bitterness but also to extinguish the bitter masking effect of homoeriodictyol in a caffeine solution. PMID:20058867

Reichelt, Katharina V; Hartmann, Beate; Weber, Berthold; Ley, Jakob P; Krammer, Gerhard E; Engel, Karl-Heinz

2010-02-10

180

Using a Simulated Industrial Setting for the Development of an Improved Solvent System for the Recrystallization of Benzoic Acid: A Student-Centered Project  

ERIC Educational Resources Information Center

|Recrystallization of benzoic acid is an excellent way to remove insoluble impurities. In a traditional organic laboratory experiment, insoluble impurities are removed through the recrystallization of benzoic acid utilizing water as the recrystallization solvent. It was our goal to develop a peer-led, problem-solving organic laboratory exercise

Hightower, Timothy R.; Heeren, Jay D.

2006-01-01

181

DFT and ab initio study of structure of dyes derived from 2-hydroxy and 2,4-dihydroxy benzoic acids  

NASA Astrophysics Data System (ADS)

We present a detailed analysis of the structural, infrared spectra and visible spectra of a series of azo dyes preparation of salicylic acid and 2,4-dihydroxy benzoic acid derivatives as the coupling component. The preparation of these azo dyes with salicylic acid and 2,4-dihydroxy benzoic acid derivatives (salicylic acid, methyl salicylate, ethyl salicylate, butyl salicylate, methyl 2,4-dihydroxy benzoate, ethyl 2,4-dihydroxy benzoate, salicylaldehyde, salicylamide, 2,4-dihydroxy benzamide, salicylaldoxime) have been investigated theoretically by performing HF and DFT levels of theory using the standard 6-31G* basis set. The optimized geometries and calculated vibrational frequencies are evaluated via comparison with experimental values. The vibrational spectral data obtained from solid phase FT-IR spectra are assigned modes based on the results of the theoretical calculations. The observed spectra are found to be in good agreement with the calculations.

Dabbagh, Hossein A.; Teimouri, Abbas; Najafi Chermahini, Alireza; Shahraki, Maryam

2008-02-01

182

DFT and ab initio study of structure of dyes derived from 2-hydroxy and 2,4-dihydroxy benzoic acids.  

PubMed

We present a detailed analysis of the structural, infrared spectra and visible spectra of a series of azo dyes preparation of salicylic acid and 2,4-dihydroxy benzoic acid derivatives as the coupling component. The preparation of these azo dyes with salicylic acid and 2,4-dihydroxy benzoic acid derivatives (salicylic acid, methyl salicylate, ethyl salicylate, butyl salicylate, methyl 2,4-dihydroxy benzoate, ethyl 2,4-dihydroxy benzoate, salicylaldehyde, salicylamide, 2,4-dihydroxy benzamide, salicylaldoxime) have been investigated theoretically by performing HF and DFT levels of theory using the standard 6-31G* basis set. The optimized geometries and calculated vibrational frequencies are evaluated via comparison with experimental values. The vibrational spectral data obtained from solid phase FT-IR spectra are assigned modes based on the results of the theoretical calculations. The observed spectra are found to be in good agreement with the calculations. PMID:17553738

Dabbagh, Hossein A; Teimouri, Abbas; Chermahini, Alireza Najafi; Shahraki, Maryam

2007-04-29

183

Influence of bleaching on flavor of 34% whey protein concentrate and residual benzoic acid concentration in dried whey proteins  

Microsoft Academic Search

Previous studies have shown that bleaching negatively affects the flavor of 70% whey protein concentrate (WPC70), but bleaching effects on lower-protein products have not been established. Benzoyl peroxide (BP), a whey bleaching agent, degrades to benzoic acid (BA) and may elevate BA concentrations in dried whey products. No legal limit exists in the United States for BP use in whey,

M. A. D. Listiyani; R. E. Campbell; R. E. Miracle; L. O. Dean; M. A. Drake

2011-01-01

184

CALIBRATION OF THE ABSORBED DOSE PRODUCED IN WATER BY BETATRON ELECTRONS WITH THE BENZOIC-ACID DOSIMETER  

Microsoft Academic Search

The benzoic acid dosimeter was used to determine the absorbed dose rate ; produced by betatron electrons at the depth of relative maximum dose in water. ; These measurements were related to the conventional and arbitrary specification ; of betatron electron exposure in terms of the reading of a Victoreen thimble ; chamber inserted in a polystyrene block. Chemical yield

N. F. Barr; M. B. Stark; J. S. Laughlin

1962-01-01

185

Augmenting the activity of antifungal agents against aspergilli using structural analogues of benzoic acid as chemosensitizing agents  

Technology Transfer Automated Retrieval System (TEKTRAN)

Structure-activity analysis revealed that antifungal activities of benzoic and gallic acids were increased against strains of Aspergillus flavus, A. fumigatus and A. terreus, causative agents of human aspergillosis, by addition of a methyl, methoxyl or a chloro group at position 4 of the aromatic ri...

186

First derivative spectrophotometric and high performance liquid chromatographic simultaneous determination of benzoic and salicylic acids in pharmaceutical preparations.  

PubMed

Two methods are presented for the simultaneous determination of benzoic and salicylic acids in pharmaceutical preparations using first (1D) derivative spectrophotometry and high-performance liquid chromatography. Benzoic and salicylic acids were determined by measurement of first derivative amplitude at the zero crossing points 283 and 310 nm respectively. Methanolic solutions obeyed Beer's law in the concentration range of 20-60 and 10-30 microg/ml for benzoic and salicylic acids respectively. The HPLC method depends upon using a Vydac reversed-phase column at ambient temperature with a mobile phase consisting of 20:80 (ACN:H2O) at a flow rate 0.5 ml min(-1) Quantitation was achieved with UV detection of 230 nm at 0 min and 204 nm at 4 min based on peak area. For the two methods the regression line equations were derived with correlation coefficient better than 0.995. The two methods were successfully applied to the simultaneous determination of benzoic and salicylic acids in laboratory-prepared mixtures and in creams with good accuracy and precision. No significant differences were found between the results obtained both by the HPLC and derivative procedures. PMID:19068560

Silva, B O

187

Amphipathic Benzoic Acid Derivativies: Synthesis and Binding in the Hydrophobic Tunnel of the Zinc Deacetylase LpxC  

SciTech Connect

The first committed step in lipid A biosynthesis is catalyzed by uridine diphosphate-(3-O-(R-3-hydroxymyristoyl))-N-acetylglucosamine deacetylase (LpxC), a zinc-dependent deacetylase, and inhibitors of LpxC may be useful in the development of antibacterial agents targeting a broad spectrum of Gram-negative bacteria. Here, we report the design of amphipathic benzoic acid derivatives that bind in the hydrophobic tunnel in the active site of LpxC. The hydrophobic tunnel accounts for the specificity of LpxC toward substrates and substrate analogues bearing a 3-O-myristoyl substituent. Simple benzoic acid derivatives bearing an aliphatic 'tail' bind in the hydrophobic tunnel with micromolar affinity despite the lack of a glucosamine ring like that of the substrate. However, although these benzoic acid derivatives each contain a negatively charged carboxylate 'warhead' intended to coordinate to the active site zinc ion, the 2.25 {angstrom} resolution X-ray crystal structure of LpxC complexed with 3-(heptyloxy)benzoate reveals 'backward' binding in the hydrophobic tunnel, such that the benzoate moiety does not coordinate to zinc. Instead, it binds at the outer end of the hydrophobic tunnel. Interestingly, these ligands bind with affinities comparable to those measured for more complicated substrate analogue inhibitors containing glucosamine ring analogues and hydroxamate 'warheads' that coordinate to the active site zinc ion. We conclude that the intermolecular interactions in the hydrophobic tunnel dominate enzyme affinity in this series of benzoic acid derivatives.

Shin,H.; Gennadios, H.; Whittington, D.; Christianson, D.

2007-01-01

188

In vitro predictions of skin absorption of caffeine, testosterone, and benzoic acid: a multi-centre comparison study  

Microsoft Academic Search

To obtain better insight into the robustness of in vitro percutaneous absorption methodology, the intra- and inter-laboratory variation in this type of study was investigated in 10 European laboratories. To this purpose, the in vitro absorption of three compounds through human skin (9 laboratories) and rat skin (1 laboratory) was determined. The test materials were benzoic acid, caffeine, and testosterone,

J. J. M. van de Sandt; J. A. van Burgsteden; S. Cage; P. L. Carmichael; I. Dick; S. Kenyon; G. Korinth; F. Larese; J. C. Limasset; W. J. M. Maas; L. Montomoli; J. B. Nielsen; J.-P. Payan; E. Robinson; P. Sartorelli; K. H. Schaller; S. C. Wilkinson; F. M. Williams

2004-01-01

189

Anaerobic degradation of halogenated benzoic acids coupled to denitrification observed in a variety of sediment and soil samples  

Microsoft Academic Search

Denitrifying enrichment cultures utilizing monochlorinated benzoic acids as a carbon source were established using sediments and soils from a variety of sources as inocula. Enrichment cultures from most of the sites readily degraded 3- and 4chlorobenzoate within 24 weeks. Upon refeeding, 3- and 4-chlorobenzoate were rapidly depleted, and stable denitrifying cultures were obtained by repeated dilution and refeeding of the

Max M. Hggblom; Maria D. Rivera; Lily Y. Young

1996-01-01

190

A Fenton-like system combined by Co2+ and potassium Monopersulfate for the treatment of benzoic acid  

Microsoft Academic Search

in this paper, the Fenton-like oxidation system combined by Co 2+ and potassium Monopersulfate (PMS) for the treatment of benzoic acid (BA) was investigated. The BA degradation was increased with the increasing of Co 2+ dosage and PMS dosage. However, when the molar ratios of Co 2+ to PMS were higher than 1:50, the increase of BA degradation rates were

Liwei. Chen; Jun. Ma

2011-01-01

191

Low temperature Raman study of a liquid crystalline system 4-Decyloxy benzoic acid (4DBA)  

NASA Astrophysics Data System (ADS)

The Raman spectra of a liquid crystalline system, 4-Decyloxy benzoic acid (4DBA) have been recorded at different temperatures within the interval 300-78 K in order to identify the structural changes in crystalline state of a nematogen and to understand the molecular alignment therein. The earlier predicted dimer structure of 4DBA was optimized with DFT method and the theoretical Raman spectra of dimer as well as monomer have been calculated for comparison with the experimental spectra. The mode specific quartic coupling coefficient; Ai,? and phonon frequency; ?i have been calculated using temperature dependent anharmonic perturbation theory. The precise band shape analysis of Raman bands at 807, 881, 1255, 1282, 1436, 1576, 1604, 2881 and 3081 cm-1 gives signature of temperature induced slow crystal modification. The structural changes leading to crystal modification have been discussed.

Vikram, K.; Nandi, Rajib; Singh, Ranjan K.

2013-08-01

192

Oxidation of benzaldehydes to benzoic acid derivatives by three Desulfovibrio strains.  

PubMed Central

Desulfovibrio vulgaris Marburg, "Desulfovibrio simplex" XVI, and Desulfovibrio sp. strain MP47 used benzaldehydes such as vanillin, 3,4,5-trimethoxybenzaldehyde, protocatechualdehyde, syringaldehyde, p-anisaldehyde, p-hydroxybenzaldehyde, and 2-methoxybenzaldehyde as electron donors for sulfate reduction and carbon dioxide and/or components of yeast extract as carbon sources for cell synthesis. The aldehydes were oxidized to their corresponding benzoic acids. The three sulfate reducers oxidized up to 7 mM vanillin and up to 4 mM p-anisaldehyde. Higher concentrations of vanillin or p-anisaldehyde were toxic. In addition, pyridoxal hydrochloride and o-vanillin served as electron donors for sulfate reduction. Salicylaldehyde, pyridine-2-aldehyde, pyridine-4-aldehyde, and 4-hydroxy-3-methoxybenzylalcohol were not oxidized. No molecular hydrogen was detected in the gas phase. The oxidized aldehydes were not further degraded.

Zellner, G; Kneifel, H; Winter, J

1990-01-01

193

Dihydroxy(4-thiomorpholinomethyl)benzoic acid: from molecular asymmetry to diode characteristics.  

PubMed

One of the challenges in molecular electronics is to design molecules which can be used as functional units in electronic devices. The subject of our investigations is an asymmetrical molecule, dihydroxy(4-thiomorpholinomethyl)benzoic acid (TMBA), whose structural and electronic properties are characterized. The self-assembly behavior of TMBA on Au(111) surfaces resulting in highly ordered monolayers is obtained using scanning tunneling microscopy (STM). Furthermore, investigations on the electronic properties of the combined metal/molecule system reveal an orbital mediated tunneling process and tunneling decay constants for the carboxylic and thiomorpholino group. Thus, a diode-like character of TMBA is shown to be caused by intrinsic electronic properties of different molecular moieties. PMID:21749130

Lennartz, M Christina; Baumert, Miriam; Karthuser, Silvia; Albrecht, Markus; Waser, Rainer

2011-07-20

194

Concentration dependent dual fluorescence of 4-( N, N-dimethylamino)benzoic acid in chloroform  

NASA Astrophysics Data System (ADS)

The intramolecular charge transfer (ICT) dual fluorescence of 4-( N, N-dimethylamino)benzoic acid (DMABOA) in chloroform was found concentration dependent and the fluorescence quantum yield ratio of the ICT to the locally excited (LE) state band, ?'/?, increases with DMABOA concentration. Whereas the shape of absorption spectrum remains unchanged, the IR data establish the formation of ground state intermolecular hydrogen bonding between DMABOA molecules. The excitation spectra of DMABOA corresponding to the ICT and the LE emission were found identical at each DMABOA concentration but changing with increasing DMABOA concentration. These observations point to the possibility that the H-bonding mediated excited-state proton transfer facilitates the intramolecular charge transfer process.

Jiang, Yun-Bao

1999-04-01

195

Intermolecular potential for benzoic acid water based on the test-particle model and statistical mechanical simulations of benzoic acid in aqueous solutions  

NASA Astrophysics Data System (ADS)

Structures and interaction energies of benzoic acid-water (BA-H 2O) 1:1, 1:2, 2:1 and 2:2 complexes were investigated using intermolecular potentials derived from the test-particle model (T-model). The absolute and some lowest-lying minimum energy geometries of the 1:1 and 1:2 complexes were examined using ab initio calculations with the Hartree-Fock (HF) and the second order Mller-Plesset (MP2) perturbation theories. The T-model, HF and MP2 calculations revealed that cyclic arrangements of hydrogen bonds (H-bonds) between the COOH group and H 2O represent the absolute minimum energy geometries of the 1:1 and 1:2 complexes. The results on the 2:1 and 2:2 complexes showed that the cyclic H-bonds in the dimers could be opened to allow insertion of water molecules. Based on the T-model potentials, aqueous solutions of BA and (BA) 2 were investigated by conducting a series of molecular dynamic (MD) simulations. It was found that, except at the solute-solute H-bonds, the hydration structures of the cyclic H-bond planar (CHP) and side-on type (SOT) dimers are not substantially different from a single BA. The atom-atom pair correlation functions ( g( R)) derived from MD simulations suggested that, in very dilute aqueous solution, the cyclic H-bonds in the CHP and SOT dimers are not stable and can be disrupted by the solute-solvent H-bond interaction and thermal energy fluctuation.

Sagarik, Kritsana; Rode, Bernd M.

2000-10-01

196

2-(2-Methyl-benzo-yl)benzoic acid: catemeric hydrogen bonding in a ?-keto acid1  

PubMed Central

The crystal structure of the title compound, C15H12O3, displays catemeric aggregation involving OH?O hydrogen bonds progressing from the carboxyl group of one molecule to the ketone O atom of another glide-related neighbor. The molecule is twisted, with the toluene 80.61?(3) out of plane with respect to the phenyl group of the benzoic acid. The acid group makes a dihedral angle of 13.79?(14) with the attached phenyl ring. The molecules are achiral, but the space group glide planes create alternating conformational chirality in the chain units. The four hydrogen-bonding chains progress along [001] in an AABB pattern (right-to-left versus left-to-right), and are related to each other by the center of symmetry at (0.5, 0.5, 0.5) in the chosen cell. There is one close contact (2.54?) between a phenyl H atom and the acid carbonyl from a symmetry-related molecule.

Platosz, Natalia A.; Lalancette, Roger A.; Thompson, Hugh W.; Newman, Jacob M.; Schachter, Ari

2013-01-01

197

Different combinations of formic, propionic and benzoic acids in slaughter offal preservation for feeding to fur animals  

Microsoft Academic Search

Washed rumens, intestines and lungs of beef cattle, were ground, homogenized and acidified with formic acid, 6 g kg?1. The acidified offal was divided into 30 plastic buckets, assigned to two storage temperatures (4C, 20C) and 5 treatments with propionic and benzoic acids, (in g kg?1): 0+0, 2+0, 1+1, 0+2 and 3+1. At 4C, the organoleptic quality of the silages

Ilpo Plnen; Vesa Toivonen; Jaakko Mkel

1998-01-01

198

Esterification of benzoic acid and glycerol to ?-monobenzoate glycerol in solventless media using an industrial free Candida antarctica lipase B  

Microsoft Academic Search

The enzymatic reaction of benzoic acid and glycerol in the absence of organic solvents to obtain the 1- or 3-monobenzoate glycerol (?-MBG) is studied. Esterification runs were batch wise performed with a concentration of enzyme of 30g\\/L, changing the initial concentration of the acid in glycerol from 20 to 60g\\/L, and temperature from 50 to 70C. In these conditions, the

J. J. Tamayo; M. Ladero; V. E. Santos; F. Garca-Ochoa

199

Effects of toluene and benzoic acid on the kinetics of ferrous oxidation on Pt and nafion-coated Pt electrodes  

SciTech Connect

The electrochemical kinetics of Fe[sup 2+] oxidation to Fe[sup 3+] have been investigated by cyclic and ring disk electrode voltammetry in the absence and presence of the contaminants toluene (7 mM, saturated solution) or benzoic acid (16 mM) in 1M H[sub 2]SO[sub 4] electrolyte on (1) smooth Pt electrodes, (2) Nafion-coated smooth Pt electrodes, and (3) Pt electrodes electrodeposited within a Nafion film coated onto a glassy carbon (GC) substrate. On uncoated Pt, the kinetics are adversely affected by these two organics: both the anodic transfer coefficient and the apparent standard rate constant are decreased. A 3.7 [mu]m Nafion coating, however, effectively buffers the smooth Pt electrode from toluene, but, nevertheless, benzoic acid still affects the reaction rate. In contrast, the transfer coefficient and rate constant for Fe[sup 2+] oxidation on the Pt/Nafion/GC electrode are essentially unaffected by either toluene or benzoic acid. Qualitative features of the voltammograms also indicate that the Nafion film protects the Pt from contamination by these aromatics: two current plateaus are observed using an uncoated Pt electrode in the presence of toluene or benzoic acid with a ratio which increased with rotation rate; with the Nafion coating on a smooth Pt electrode and in the presence of toluene, however, there is only one current plateau; in the presence of benzoic acid, two current plateaus remain, but the ratio is nearer unity and less sensitive to rotation rate. In contrast, only a single plateau current is observed using the Pt/Nafion/GC electrode. The Nafion coating is apparently an effective buffer layer against these two aromatics, but concurrently affects a decrease in the mass-transfer limited current due to the diffusional resistance of the film.

Ye, J.H.; Fedkiw, P.S. (North Carolina State Univ., Raleigh, NC (United States). Dept. of Chemical Engineering)

1994-06-01

200

Online preconcentration in capillary electrophoresis with contactless conductivity detection for sensitive determination of sorbic and benzoic acids in soy sauce.  

PubMed

A sensitive method of online preconcentration followed by capillary electrophoresis with capacitively coupled contactless conductivity detection (CE-C(4)D) is evaluated as a novel approach for the determination of benzoic acid and sorbic acid in soy sauce. The online preconcentration technique, namely field-enhanced sample injection, coupled with CE-C(4)D were successfully developed and optimized. In order to reduce the complex matrix interference resulting from the constituents of soy sauce, a suitable sample clean-up procedure was also investigated for real sample pretreatment. Under optimized conditions, sorbic acid and benzoic acid were well separated within 10 min, and the detection limits were 0.05 ?M (5.6 ?g L(-1)) and 0.08 ?M (9.8 ?g L(-1)), respectively. The accuracy was tested by spiking 10.0 mg L(-1) and 100.0 mg L(-1) of standards in the soy sauce samples, and the recoveries were 95-99%, respectively. Results of this study show a great potential for the proposed method as a tool for the fast screening of benzoic acid and sorbic acid in a complex matrix. PMID:21238741

Wei, Ruixia; Li, Wenhua; Yang, Lirong; Jiang, Yixiu; Xie, Tianyao

2010-11-23

201

Synthesis of 5-nitro-2-(N-3-(4-azidophenyl)-propylamino)-benzoic acid: Photoaffinity labeling of human red blood cell ghosts with a 5-nitro-2-(3-phenylpropylamino)-benzoic acid analog  

SciTech Connect

A photoaffinity analog of the potent epithelial chloride channel blocker 5-nitro-2-(3-phenylpropylamino)-benzoic acid has been synthesized and characterized. In the dark, this reagent, 5-nitro-2-(N-3-(4-azidophenyl)-propylamino)-benzoic acid, and the parent compound reversibly inhibited chloride efflux in human red blood cell ghosts. Irradiation of ghost membranes with 350 microM arylazide analog reduced the rate of chloride efflux to 33% of the control value. The photoinactivation process was not reversed by exhaustive washing of ghost membranes. Covalent incorporation of the photoaffinity reagent was supported by difference ultraviolet spectroscopy, which indicated the attachment of the substituted 2-amino-5-nitrobenzoic acid chromophore to ghost membranes. The novel photolabeling agent described here should be a useful structural probe for chloride channels in erythrocyte membranes and epithelial cells.

Branchini, B.R.; Murtiashaw, M.H.; Egan, L.A. (Connecticut Coll., New London (USA))

1991-04-15

202

Effect of the chemical specificity of benzoic acid and its analogs on osmotic fragility in erythrocytes of Sprague-Dawley rats in vitro.  

PubMed

We examined the chemical specificity of benzoic (benzene-carboxylic) acid and its derivatives in increasing osmotic fragility (OF) in rat red blood cells (RBCs) in vitro. Benzoic acid increased the OF in the rat RBCs in a dose-dependent manner. Replacement of the carboxylic group with a phosphoric group also increased the OF in RBCs, whereas substitution of the carboxylic group by a sulfonic, amide or hydroxy group did not affect the OF. Replacement of the benzene nucleus with a cyclohexane ring or a straight hydrocarbon chain with six carbons resulted in a greater increase in OF than that induced by benzoic acid. Introduction of a methyl group, chloride or bromide at the m- and p-positions of the benzene ring considerably enhanced the increase in OF induced by benzoic acid. Substitution of the amino and hydroxy group at the m- and p- positions abolished the increase in OF induced by benzoic acid. The introduction of these elements at the o-position showed an almost equal increase in OF as that observed for benzoic acid. A molecule of benzoic acid is composed of both hydrophilic (carboxylic group) and hydrophobic (benzene ring) components. Replacement of the hydrophilic component changed the balance formed between hydrophobic and hydrophilic components in the moiety, resulting alterations to its interaction with the RBC membrane. The size, form and elements introduced into the benzene ring also affected its affinity to the cell membrane, and changed the osmotic resistance in rat RBCs. PMID:23376564

Mineo, Hitoshi; Ogita, Ai; Kanayama, Nozomi; Kawagishi, Mai; Sato, Eiko; Yamamoto, Nodoka; Arai, Kohei; Izawa, Masa-aki

2013-01-30

203

Completion of the core ?-oxidative pathway of benzoic acid biosynthesis in plants.  

PubMed

Despite the importance of benzoic acid (BA) as a precursor for a wide array of primary and secondary metabolites, its biosynthesis in plants has not been fully elucidated. BA formation from phenylalanine requires shortening of the C(3) side chain by two carbon units, which can occur by a non-?-oxidative route and/or a ?-oxidative pathway analogous to the catabolism of fatty acids. Enzymes responsible for the first and last reactions of the core BA ?-oxidative pathway (cinnamic acid ? cinnamoyl-CoA ? 3-hydroxy-3-phenylpropanoyl-CoA ? 3-oxo-3-phenylpropanoyl-CoA ? BA-CoA) have previously been characterized in petunia, a plant with flowers rich in phenylpropanoid/benzenoid volatile compounds. Using a functional genomics approach, we have identified a petunia gene encoding cinnamoyl-CoA hydratase-dehydrogenase (PhCHD), a bifunctional peroxisomal enzyme responsible for two consecutively occurring unexplored intermediate steps in the core BA ?-oxidative pathway. PhCHD spatially, developmentally, and temporally coexpresses with known genes in the BA ?-oxidative pathway, and correlates with emission of benzenoid volatiles. Kinetic analysis of recombinant PhCHD revealed it most efficiently converts cinnamoyl-CoA to 3-oxo-3-phenylpropanoyl-CoA, thus forming the substrate for the final step in the pathway. Down-regulation of PhCHD expression in petunia flowers resulted in reduced CHD enzyme activity, as well as decreased formation of BA-CoA, BA and their derived volatiles. Moreover, transgenic lines accumulated the PhCHD substrate cinnamoyl-CoA and the upstream pathway intermediate cinnamic acid. Discovery of PhCHD completes the elucidation of the core BA ?-oxidative route in plants, and together with the previously characterized CoA-ligase and thiolase enzymes, provides evidence that the whole pathway occurs in peroxisomes. PMID:22988098

Qualley, Anthony V; Widhalm, Joshua R; Adebesin, Funmilayo; Kish, Christine M; Dudareva, Natalia

2012-09-17

204

Effects of dietary benzoic acid and sodium-benzoate on performance, nitrogen and mineral balance and hippuric acid excretion of piglets  

Microsoft Academic Search

The objective of this study was to compare the effects of sodium-benzoate (NaB) with those of benzoic acid (BAc) on growth performance of piglets as well as nutrient digestibility, nitrogen and mineral balance, urinary pH, and the urinary excretion of BAc and hippuric acid (HAc). The study was conducted with 120 weaning piglets (6.5kg body weight), divided in four groups

Tobias Grber; Holger Kluge; Frank Hirche; Ji? Bro; Gabriele I. Stangl

2012-01-01

205

Development of an RP-HPLC method for the simultaneous determination of benzoic acid, sorbic acid, natamycin and lysozyme in hard and pasta filata cheeses  

Microsoft Academic Search

A single method, based on RP-HPLC with UV detection, was developed with the aim of simultaneously quantifying four preservatives in cheeses: benzoic acid, sorbic acid, natamycin and lysozyme.The preservatives were extracted from different cheeses by using the same procedure, and separated by a single RP-HPLC gradient elution showing good resolution, in a short time.Recoveries were always higher than 91%; MDLs

Chiara Guarino; Fabio Fuselli; Alessandro La Mantia; Lucia Longo

2011-01-01

206

3,4,5TRIHYDROXY BENZOIC ACID (GALLIC ACID), THE HEPATOPROTECTIVE PRINCIPLE IN THE FRUITS OF TERMINALIA BELERICA BIOASSAY GUIDED ACTIVITY  

Microsoft Academic Search

CompoundIisolated from fraction TB5 ofTerminalia belericaand finally identified as 3,4,5-trihydroxy benzoic acid (gallic acid) was evaluated for its hepatoprotective activity against carbon tetrachloride (CCl4)-induced physiological and biochemical alterations in the liver. The main parameters studied were hexobarbitone-induced sleep, zoxazolamine induced paralysis, serum levels of transaminases and bilirubin. The hepatic markers assessed were lipid peroxidation, drug metabolising enzymes, glucose-6-phosphatase and triglycerides.

K. K Anand; B Singh; A. K Saxena; B. K Chandan; V. N Gupta; V Bhardwaj

1997-01-01

207

Simultaneous Determination of Benzoic Acid and Sorbic Acid in Food Products by CE after On-line Preconcentration by Dynamic pH Junction  

Microsoft Academic Search

An online dynamic pH junction method has been proposed for sensitive determination of benzoic acid (BA) and sorbic acid (SA)\\u000a by capillary electrophoresis (CE). It was based on the decreased mobility of the analytes when they migrated from sample zone\\u000a with low pH to background electrolytes with high pH. Under optimized conditions, the limits of detection (S\\/N=3) of BA and

Xinfeng Zhang; Shuxia Xu; Yonghua Sun; Yanyan Wang; Cheng Wang

2011-01-01

208

Voltammetric studies of 2-hydroxy-5-[(4-sulfophenyl)azo]benzoic acid as a novel prodrug of 5-aminosalicylic acid  

Microsoft Academic Search

The electrochemical properties of a colon-targeted prodrug of 5-aminosalicylic acid (5-ASA), 2-hydroxy-5-[(4-sulfophenyl)azo]benzoic acid (SPSA), were investigated in aqueous solutions at glassy carbon electrodes using cyclic voltammetry and controlled potential electrolysis. The influence of the pH and experimental time domain on the reaction pathway has been studied. The electrochemical reduction of SPSA is identified as an ECE process always leading to

Biljana Nigovi?; Zoran Mandi?; Branimir imuni?; Ines Fistri?

2001-01-01

209

Artificial Neural Network Prediction for Thermal Decomposition of Potassium Nitrate (KNO3) and Benzoic Acid (C6H5COOH)  

NASA Astrophysics Data System (ADS)

The aim of this work is to correlate the results of experimental data by using the differential thermal analysis (DTA) method and predictions of artificial neural networks (ANNs). Thermal decomposition of potassium nitrate (KNO3) and benzoic acid (C6H5COOH) have been analyzed by the simultaneous DTA method. Kinetic parameters (critical points, the change of enthalpy) have been investigated. A computer model, based on multilayer feed-forwarding back-propagation is used for the prediction of critical points, phase transitions of potassium nitrate (KNO3) and benzoic acid (C6H5COOH). As a result of our study, we conclude that the ANN model shows a considerably good result about the prediction of experimental data.

Beken, Murat

210

Natural oils affect the human skin integrity and the percutaneous penetration of benzoic acid dose-dependently.  

PubMed

Natural oils are extensively used in cosmetics and as treatment for a growing number of more or less specific ailments. Skin irritation and cases of allergy have repeatedly been described in the literature following exposure to these oils. The present study evaluated the extent to which three natural oils (eucalyptus oil, tea tree oil, peppermint oil) would affect the skin integrity and the percutaneous penetration of benzoic acid when applied topically in relevant concentrations. An experimental in vitro model using static diffusion cells mounted with human breast or abdominal skin was applied. The three natural oils decreased the skin integrity dose-dependently. Concomitant dermal exposure to low concentrations of peppermint oil reduced the percutaneous penetration of benzoic acid. The present study lends support to the notion that low concentrations of peppermint oil may act protective against percutaneous penetration of some chemicals, whereas higher concentrations may decrease the integrity of the dermal barrier. PMID:16700820

Nielsen, Jesper B

2006-06-01

211

p-Hydroxy-benzoic acid as an adhesion promoter for rubber compounds to a brass-plated steel cord  

Microsoft Academic Search

The adhesion between a p-hydroxy-benzoic acid (POB) containing rubber compounds and a brass-plated steel cord was investigated to understand the role of POB as an adhesion promoter. The cure rate slowed down when POB was added to the rubber compound, but changes in the physical properties were not significant. An improvement in adhesion was seen with a low loading of

Gyung Soo Jeon; Gon Seo

2001-01-01

212

2-[5-(2-Fluoro-phen-yl)-3-isobutyl-1H-pyrazol-1-yl]benzoic acid  

PubMed Central

In the title compound, C20H19FN2O2, the dihedral angle between the aromatic rings is 62.1?(1), and those between the pyrazole ring and the fluorobenzene and benzoic acid rings are 52.1?(1) and 53.1?(1), respectively. In the crystal, molecules are linked into [010] C(7) chains by OH?N hydrogen bonds.

Sreenivasa, S.; Manojkumar, K. E.; Suchetan, P. A.; Mohan, N. R.; Kumar, Vijith; Palakshamurthy, B. S.

2013-01-01

213

Synthesis, antimicrobial evaluation, ot-QSAR and mt-QSAR studies of 2-amino benzoic acid derivatives  

Microsoft Academic Search

A series of 2-amino benzoic acid derivatives (128) were synthesized and evaluated for their in vitro antimicrobial activity against the panel of Gram positive, Gram negative\\u000a bacterial and fungal strains. The results of antimicrobial studies indicated that, in general, the synthesized compounds were found to be bacteriostatic\\u000a and fungistatic in action. QSAR studies performed by the development of one target

Kuldeep Mahiwal; Pradeep Kumar; Balasubramanian Narasimhan

214

Partial Molar and Ultrasonic Properties of Benzoic and Phenyl Acetic Acids in Water and Water + Alcohol Mixtures  

Microsoft Academic Search

Partial molar volumes of Benzoic and Phenylacetic acids have been determined in water and water + alcohol (5 wt% each of methanol, ethanol and propanol) mixtures from density measurements in varying ranges of concentration at four different temperatures in the interval of 10 from 288.15 to 318.15 K. The density data have been used to obtain partial molar volumes, co-efficients

U. N. Dash; B. K. Mohanty

1999-01-01

215

2,3-Diamino-pyridinium 3-chloro-benzo-ate-3-chloro-benzoic acid (1/1)  

PubMed Central

The asymmetric unit of the title compound, C5H8N3 +C7H4ClO2 ?C7H5ClO2, contains an ion pair and a 3-chlorobenzoic acid molecule. In the cation, the pyridine N atom is protonated. In the crystal, the components are connected via NH?O, OH?O and CH?O hydrogen bonds, thereby forming sheets lying parallel to (100).

Hemamalini, Madhukar; Goh, Jia Hao; Fun, Hoong-Kun

2011-01-01

216

Simultaneous determination of sorbic and benzoic acids in food dressing by headspace solid-phase microextraction and gas chromatography  

Microsoft Academic Search

A facile headspace solid-phase microextraction (HS-SPME) procedure using 85?m polyacrylate (PA) fiber is presented for the simultaneous determination of preservatives (sorbic and benzoic acids) in food dressing, including Thousand Island Dressing, HellMANN'S Salad Dressing and Tomato Ketchup, by gas chromatography (GC) with flame ionization detector (FID). The method presented preserves the advantages typical of HS-SPME such as simplicity, low intensity

Chunzhou Dong; Yong Mei; Lin Chen

2006-01-01

217

Headspace solid-phase microextraction applied to the simultaneous determination of sorbic and benzoic acids in beverages  

Microsoft Academic Search

A new analytical procedure was developed using headspace solid-phase microextraction (HS-SPME) for the simultaneous determination of sorbic and benzoic acids in beverages. The sample were processed depending on their nature, either only diluted with water, or treated with a NaOH solution and filtered through a 0.45-?m membrane filter. The samples were heated in a vial in the presence of sulfuric

Chunzhou Dong; Wenfang Wang

2006-01-01

218

Photoacoustic and luminescence properties study on energy transfer and relaxation processes of Tb(III) complexes with benzoic acid  

Microsoft Academic Search

The photoacoustic (PA) amplitude spectra of Tb(Benz)3, Tb(Benz)3Phen and Tb(Benz)3Bpy complexes (Benz: benzoic acid; Phen: 1,10-phenanthroline; Bpy: 2,2?-bipyridine) have been measured, and the PA phase data of the different complexes calculated. The PA amplitude spectra combined with the luminescence spectra reflected the variation of the luminescence properties, and the PA phase is directly relative to the relaxation time. The luminescence

Xijuan Yu; Qingde Su

2003-01-01

219

Reduction of Benzenoid Synthesis in Petunia Flowers Reveals Multiple Pathways to Benzoic Acid and Enhancement in Auxin Transport  

Microsoft Academic Search

In plants, benzoic acid (BA) is believed to be synthesized from Phe through shortening of the propyl side chain by two carbons. It is hypothesized that this chain shortening occurs via either a b-oxidative or non-b-oxidative pathway. Previous in vivo isotope labeling and metabolic flux analysis of the benzenoid network in petunia (Petunia hybrida) flowers revealed that both pathways yield

Irina Orlova; Amy Marshall-Colon; Jennifer Schnepp; Barbara Wood; Marina Varbanova; Eyal Fridman; Joshua J. Blakeslee; W. A. Peer; A. S. Murphy; D. Rhodes; E. Pichersky; N. Dudareva

2006-01-01

220

Spectral Study of the Co?luminescence Effect of Lanthanide Ternary Complexes with Benzoic Acid and Phenanthroline  

Microsoft Academic Search

The photoacoustic (PAS) spectra and luminescence spectra of Eu(Hba)3 Phen and coprecipitates Eu0.6Ln0.4(Hba)3 Phen complexes (Ln:Y, Nd; Hba: benzoic acid; Phen: phenanthroline) have been measured, and the co?luminescence effect of the coprecipitates are reported. The PAS intensities of the central lanthanide ions are interpreted in terms of the probability of nonradiative transitions. It is found that the PAS intensity of

Yuetao Yang; Shuyi Zhang

2004-01-01

221

Chemiluminescence of benzoic and cinnamic acids, and flavonoids in the presence of aldehyde and hydrogen peroxide or hydroxyl radical by fenton reaction  

Microsoft Academic Search

Light emission (chemiluminescence; CL) was observed by exciting phenolic compounds with hydrogen peroxide (H2O2) or hydroxyl radical (HO), formed from H2 and FeCl2 by the Fenton reaction. The intensity of the CL of benzoic acid derivatives in the presence of (H2 was in the order of gallic acid > caffeic acid > 3,5-dimethoxy-4-hydroxycinnamic acid > isovanillic acid = syringic acid.

Yumiko Yoshiki; Kazuyoshi Okubo; Masamichi Onuma; Kiharu Igarashi

1995-01-01

222

Isotope effects associated with tunneling and double proton transfer in the hydrogen bonds of benzoic acid.  

PubMed

The isotope effects associated with double proton transfer in the hydrogen bonds of benzoic acid (BA) dimers have been measured using field-cycling (1)H NMR relaxometry and quasielastic neutron scattering. By studying mixed isotope (hydrogen and deuterium) samples, the dynamics of three isotopologues, BA-HH, BA-HD, and BA-DD, have been investigated. Low temperature measurements provide accurate measurements of the incoherent tunneling rate, k(0). This parameter scales accurately with the mass number, m, according to the formula k(0)=(E/m)e(-Fm) providing conclusive evidence that the proton transfer process is a strongly correlated motion of two hydrons. Furthermore, we conclude that the tunneling pathway is the same for the three isotopologue species. Measurements at higher temperatures illuminate the through barrier processes that are mediated via intermediate or excited vibrational states. In parallel with the investigation of proton transfer dynamics, the theoretical and experimental aspects of studying spin-lattice relaxation in single crystals of mixed isotope samples are investigated in depth. Heteronuclear dipolar interactions between (1)H and (2)H isotopes contribute significantly to the overall proton spin-lattice relaxation and it is shown that these must be modeled correctly to obtain accurate values for the proton transfer rates. Since the sample used in the NMR measurements was a single crystal, full account of the orientation dependence of the spin-lattice relaxation with respect to the applied B field was incorporated into the data analysis. PMID:15268141

Xue, Q; Horsewill, A J; Johnson, M R; Trommsdorff, H P

2004-06-15

223

Proton transfer in benzoic acid crystals: Another look using quantum operator theory  

NASA Astrophysics Data System (ADS)

We present a calculation of the rate of synchronous double proton transfer in benzoic acid crystals. Experiments on these systems have been performed over a wide range of temperatures (roughly 10-400 K). Even though the energetic barrier for proton transfer is rather high, the observed activation energy is low, while kinetic isotope experiments seem to indicate classical transfer. The system exhibits significant quantum character even at high temperatures and we show that the observed low activation energies can be reproduced assuming that the reaction is ``assisted'' by a low-frequency intramolecular mode, as has been suggested in different contexts by Benderskii [V. A. Benderskii, S. Yu. Grebenshchikov, and G. V. Mil'nikov, Chem. Phys. 194, 1 (1995)], Hynes [D. Borgis and J. Hynes, J. Chem. Phys. 94, 3619 (1991)] and Silbey [A. Suarez and R. Silbey, J. Chem. Phys. 94, 4809 (1991)]. We use our previous work on the quantum Kramers problem to perform a fully quantum calculation that incorporates symmetric coupling to the intramolecular mode and coupling to the condensed environment to all orders. We calculate the activation energies for hydrogen and deuterium transfer and we show that our results are in quantitative agreement with the experiment.

Antoniou, Dimitri; Schwartz, Steven D.

1998-08-01

224

Influence of alternative electron acceptors on the anaerobic biodegradability of chlorinated phenols and benzoic acids.  

PubMed Central

Nitrate, sulfate, and carbonate were used as electron acceptors to examine the anaerobic biodegradability of chlorinated aromatic compounds in estuarine and freshwater sediments. The respective denitrifying, sulfidogenic, and methanogenic enrichment cultures were established on each of the monochlorinated phenol and monochlorinated benzoic acid isomers, using sediment from the upper (freshwater) and lower (estuarine) Hudson River and the East River (estuarine) as source materials. Utilization of each chlorophenol and chlorobenzoate isomer was observed under at least one reducing condition; however, no single reducing condition permitted the metabolism of all six compounds tested. The anaerobic biodegradation of the chlorophenols and chlorobenzoates depended on the electron acceptor available and on the position of the chlorine substituent. In general, similar activities were observed under the different reducing conditions in both the freshwater and estuarine sediments. Under denitrifying conditions, degradation of 3- and 4-chlorobenzoate was accompanied by nitrate loss corresponding reasonably to the stoichiometric values expected for complete oxidation of the chlorobenzoate to CO2. Under sulfidogenic conditions, 3- and 4-chlorobenzoate, but not 2-chlorobenzoate, and all three monochlorophenol isomers were utilized, while under methanogenic conditions all compounds except 4-chlorobenzoate were metabolized. Given that the pattern of activity appears different for these chlorinated compounds under each reducing condition, their biodegradability appears to be more a function of the presence of competent microbial populations than one of inherent molecular structure.

Haggblom, M M; Rivera, M D; Young, L Y

1993-01-01

225

Hygroscopicity of internally mixed aerosol particles containing benzoic acid and inorganic salts  

NASA Astrophysics Data System (ADS)

The hygroscopic behaviors of benzoic acid (BA) particles and internal mixtures of inorganic salts (sodium chloride and ammonium sulfate) and BA are investigated in the 10-90% RH using the hygroscopicity tandem differential mobility analyzer (H-TDMA) system. Different morphology of BA, NaCl-BA, and (NH4)2SO4-BA particles at representative RH is characterized by Transmission Electron Microscopy (TEM). The hygroscopic growth factors (GFs) of BA exhibit a significant reduction in the 75-85% RH, followed by a slight increase at 90% RH. Internally mixed NaCl-BA and (NH4)2SO4-BA particles display deliquescence transitions at 70% RH, followed by apparently hampered hygroscopic growth due to the presence of BA. According to the TEM results, the morphology of BA particles and mixed particles show marked change in humidification, which possibly can be attributed to the strong microstructural rearrangement of BA fraction. This significant restructuring is responsible for the GFs change of BA particles and the hygroscopic behaviors transformation of mixed NaCl-BA and (NH4)2SO4-BA particles. These results demonstrate that atmospheric BA could significantly influence the hygroscopic properties of inorganic aerosols.

Shi, Yajun; Ge, Maofa; Wang, Weigang

2012-12-01

226

Isotope effects associated with tunneling and double proton transfer in the hydrogen bonds of benzoic acid  

NASA Astrophysics Data System (ADS)

The isotope effects associated with double proton transfer in the hydrogen bonds of benzoic acid (BA) dimers have been measured using field-cycling 1H NMR relaxometry and quasielastic neutron scattering. By studying mixed isotope (hydrogen and deuterium) samples, the dynamics of three isotopologues, BA-HH, BA-HD, and BA-DD, have been investigated. Low temperature measurements provide accurate measurements of the incoherent tunneling rate, k0. This parameter scales accurately with the mass number, m, according to the formula k0=(E/m)e-Fm providing conclusive evidence that the proton transfer process is a strongly correlated motion of two hydrons. Furthermore, we conclude that the tunneling pathway is the same for the three isotopologue species. Measurements at higher temperatures illuminate the through barrier processes that are mediated via intermediate or excited vibrational states. In parallel with the investigation of proton transfer dynamics, the theoretical and experimental aspects of studying spin-lattice relaxation in single crystals of mixed isotope samples are investigated in depth. Heteronuclear dipolar interactions between 1H and 2H isotopes contribute significantly to the overall proton spin-lattice relaxation and it is shown that these must be modeled correctly to obtain accurate values for the proton transfer rates. Since the sample used in the NMR measurements was a single crystal, full account of the orientation dependence of the spin-lattice relaxation with respect to the applied B field was incorporated into the data analysis.

Xue, Q.; Horsewill, A. J.; Johnson, M. R.; Trommsdorff, H. P.

2004-06-01

227

Effect of vanadia on the performance of NiO in vapor-phase oxidative decarboxylation of benzoic acid to phenol  

Microsoft Academic Search

A series of vanadia-loaded NiO catalysts was tested for the vapor-phase oxidative decarboxylation of benzoic acid to phenol at 673 K. NiO catalyzed the selective formation of phenol at low conversions of benzoic acid. However, the phenol yield declined with time on stream. Introduction of vanadium oxide to the catalyst resulted in pronounced improvements in the phenol yield and its

Seiichi Ohyama; Kristoffer E Popp; Mayfair C Kung; Harold H Kung

2002-01-01

228

Cellular and Subcellular Localization of S-Adenosyl-L-Methionine:Benzoic Acid Carboxyl Methyltransferase, the Enzyme Responsible for Biosynthesis of the Volatile Ester Methylbenzoate in Snapdragon Flowers  

Microsoft Academic Search

The benzenoid ester, methylbenzoate is one of the most abundant scent compounds detected in the majority of snapdragon (Antirrhinum majus) varieties. It is produced in upper and lower lobes of petals by enzymatic methylation of benzoic acid in the reaction catalyzed by S-adenosyl-l-methionine:benzoic acid carboxyl methyltransferase (BAMT). To identify the location of methylbenzoate biosynthesis, we conducted an extensive immunolocalization study

Natalia Kolosova; Debra Sherman; Dale Karlson; Natalia Dudareva

2001-01-01

229

Proton transfer reaction in 2-hydroxy-3-formyl benzoic acid at room temperature and 77 K and some study on AM1 potential surfaces  

Microsoft Academic Search

Proton transfer processes in 2-hydroxy-3-formyl benzoic acid (2HFBA) have been studied by means of absorption and emission spectroscopy in some non-polar and weakly polar solvents at room temperature and 77K in relation to 4-hydroxy-3-formyl benzoic acid (4HFBA). The excited state intramolecular proton transfer (ESIPT) is evidenced by a large Stokes shifted emission (10,500cm?1) due to the formation of enol tautomer

Debi Banerjee; Madhuri Mukhopadhyay; Samaresh Mukherjee

2005-01-01

230

Electrochemical oxidation of benzoic acid in water over boron-doped diamond electrodes: Statistical analysis of key operating parameters, kinetic modeling, reaction by-products and ecotoxicity  

Microsoft Academic Search

The electrochemical oxidation of benzoic acid over boron-doped diamond electrodes was studied. Experiments were conducted in a flow-through electrolytic cell at current intensities ranging from 11 to 24A, an electrolyte concentration of 0.05M and initial substrate concentrations ranging from 16 to 185mg L?1. Liquid chromatography (LC) coupled to diode array detector was employed to follow benzoic acid concentration profiles, while

Theodora Velegraki; George Balayiannis; Evan Diamadopoulos; Alexandros Katsaounis; Dionissios Mantzavinos

2010-01-01

231

Spinlattice relaxation in a guest triplet state is induced by proton tunneling in a benzoic acid host crystal  

NASA Astrophysics Data System (ADS)

Spinlattice relaxation (SLR) of the triplet state of pentacene-6,13-quinone (PQ) in n-C 11H 24, and as a guest impurity in benzoic acid, BA- h2 and the acid deuterated host, BA- d2, has been measured at temperatures near 4 K. Enhanced SLR in the BA hosts relative to n-C 11H 24 is a thermally activated process which we attribute to a phonon-assisted tunneling transition between local BA tautomer states.

Chaudhuri, D.; Schlyer, B. D.; Maki, A. H.

1991-03-01

232

Effects of fibrates on the glycine conjugation of benzoic acid in rats.  

PubMed

In the course of glycine conjugation, benzoic acid is successively converted into benzoyl-CoA and benzoylglycine by mitochondrial enzymes (i.e. benzoyl-CoA synthetase and benzoyl-CoA/glycine N-acyltransferase, respectively), utilizing ATP, CoA, and glycine. Large doses of benzoate deplete CoA from the liver, suggesting that the supply of CoA may limit the capacity for glycine conjugation. Because fibrates are known to increase hepatic CoA synthesis, we examined whether treatment with fenofibrate or bezafibrate enhanced the capacity of rats to conjugate benzoic acid with glycine. Dietary administration of fenofibrate or bezafibrate (2.5 mmol/kg of feed, for 10 days) increased hepatic CoA levels 8-10-fold, while not affecting hepatic ATP levels; only fenofibrate elevated, albeit moderately, the concentration of glycine in liver. Hepatic mitochondria isolated from fibrate-fed rats, compared with those from controls, exhibited unchanged benzoyl-CoA synthetase activity but higher benzoyl-CoA hydrolase and lower benzoyl-CoA/glycine N-acyltransferase activities. Feeding with either fibrate increased liver mass by 50-60%. Control and fibrate-fed rats were administered benzoate at different doses, one to produce a large demand for CoA (i.e. 2 mmol/kg, iv) and two others to produce smaller demands for CoA (i.e. 1 mmol/kg or 2 mmol/kg plus glycine, iv). Fenofibrate-fed rats, and to a lesser extent bezafibrate-fed animals, exhibited increased glycine conjugation capacity, as indicated by faster disappearance of benzoate from the blood and appearance of benzoylglycine in the blood and urine, compared with controls; however, fibrates were not more effective in rats receiving the benzoate dose that produced the greatest demand for CoA. In contrast, benzoylglycine formation from benzoate (0.1-1 mM) was not enhanced in liver slices from fibrate-fed rats; moreover, it was lower than control levels in slices from bezafibrate-fed animals. Bezafibrate, but not fenofibrate, given to rats in a single dose (0.5 mmol/kg, ip) decreased the elimination and glycine conjugation of benzoate, indicating that bezafibrate is a direct inhibitor of glycine conjugation. In summary, fibrates influence glycine conjugation in a complex manner. Some fibrate-induced alterations (i.e. increased benzoyl-CoA hydrolase and decreased glycine transferase activities and direct inhibition by bezafibrate) can potentially hinder conjugation of benzoate with glycine, thus precluding conclusions regarding whether increased CoA availability enhances glycine conjugation. Fibrate-induced hepatomegaly appears to significantly contribute to the increased glycine conjugation capacity of rats treated with fenofibrate or bezafibrate. PMID:9806950

Gregus, Z; Fekete, T; Halszi, E; Gyurasics, A; Klaassen, C D

1998-11-01

233

Adsorption of benzoic acid, phthalic acid on gold substrates studied by surface-enhanced Raman scattering spectroscopy and density functional theory calculations.  

PubMed

Benzoic acid (BA) and phthalic acid (PTA) are the simplest aromatic carboxylic acids, and they can be regarded as typical model compounds in investigating the interaction of aromatic carboxylic acids with metal surfaces by use of SERS spectroscopy. In this work, we have investigated the structure and adsorption behavior of benzoic acid and phthalic acid on the gold surface with combination of SERS and DFT calculation methods. The experimental results show that both BA and PTA may be adsorbed on the Au surface with a bidentate bridging structure, namely, the carboxylate group(s) being bound to gold via two oxygen atoms in the carboxylate group(s). Comparison of the observed SERS and predicted spectra of the complexes of these two substances with Au atoms indicates that BA is favorable to adsorb on the gold surface with a vertical orientation rather than a flat one, and PTA could "stand up" on the Au surface as a slight tilt with a two-legged geometry, i.e. all four oxygen atoms in two carboxylate groups interact on the metal surface. Apart from that, we compare the discrepancy of SERS spectra between those two molecules, which could be taken as a potential analysis technique in food safety field. PMID:23261703

Gao, Jiao; Hu, Yongjun; Li, Shaoxin; Zhang, Yanjiao; Chen, Xue

2012-12-07

234

Adsorption of benzoic acid, phthalic acid on gold substrates studied by surface-enhanced Raman scattering spectroscopy and density functional theory calculations  

NASA Astrophysics Data System (ADS)

Benzoic acid (BA) and phthalic acid (PTA) are the simplest aromatic carboxylic acids, and they can be regarded as typical model compounds in investigating the interaction of aromatic carboxylic acids with metal surfaces by use of SERS spectroscopy. In this work, we have investigated the structure and adsorption behavior of benzoic acid and phthalic acid on the gold surface with combination of SERS and DFT calculation methods. The experimental results show that both BA and PTA may be adsorbed on the Au surface with a bidentate bridging structure, namely, the carboxylate group(s) being bound to gold via two oxygen atoms in the carboxylate group(s). Comparison of the observed SERS and predicted spectra of the complexes of these two substances with Au atoms indicates that BA is favorable to adsorb on the gold surface with a vertical orientation rather than a flat one, and PTA could "stand up" on the Au surface as a slight tilt with a two-legged geometry, i.e. all four oxygen atoms in two carboxylate groups interact on the metal surface. Apart from that, we compare the discrepancy of SERS spectra between those two molecules, which could be taken as a potential analysis technique in food safety field.

Gao, Jiao; Hu, Yongjun; Li, Shaoxin; Zhang, Yanjiao; Chen, Xue

2013-03-01

235

An Aldehyde Oxidase in Developing Seeds of Arabidopsis Converts Benzaldehyde to Benzoic Acid1[OA  

PubMed Central

Arabidopsis (Arabidopsis thaliana) siliques synthesize high levels of benzoic acid (BA), which is incorporated into several glucosinolate compounds. The origin of BA in the siliques has not yet been determined. Here, we show that siliques have higher levels of benzaldehyde (BD)-oxidizing activity relative to leaves. The BD-oxidizing activity was purified from siliques in several chromatographic steps, and a 145-kD protein was identified as the enzyme most likely to possess this activity. The protein was trypsinized, and the sequence of the resulting peptides was determined by mass spectrometry, identifying it as the product of gene At1g04580, also designated as AAO4 (for ARABIDOPSIS ALDEHYDE OXIDASE4). AAO4 had previously been shown to be highly and specifically expressed in developing seeds, and its protein was shown to belong to a family of aldehyde oxidases. Here, we show that the AAO4 protein is an aldehyde oxidase that can use several substrates but that, among the substrates tested, has the lowest Km value (23 ?m) with BD. AAO4 is able to oxidize BD without NAD+, but its activity increases by 50% when this cofactor is added. The pH optimum of AAO4 is 7.0. Plants homozygous for a null allele in AAO4 showed a reduction of 30% to 45% in the total levels of BA in seeds as well as 7% to 9% and 32% to 38% decreases in the levels of 3-benzoyloxypropylglucosinolate and 4-benzoyloxybutylglucosinolate, respectively. Expressing AAO4 in Escherichia coli resulted in a 3-fold increase of BD-oxidizing activity in crude bacterial extracts over endogenous levels. These findings indicate that in Arabidopsis seeds, oxidation of BD contributes in part to the synthesis of BA.

Ibdah, Mwafaq; Chen, Ying-Tung; Wilkerson, Curtis G.; Pichersky, Eran

2009-01-01

236

Comparison of salicylic acid, benzoic acid and p-hydroxybenzoic acid for their ability to induce flowering in Lemna Gibba G3  

SciTech Connect

The long-day plant Lemna gibba G3 fails to flower under continuous light on NH/sub 4//sup +/-free 0.5 H medium. This inhibition is completely reversed by 10 ..mu..M salicyclic acid (SA) or 32 ..mu..M benzoic acid (BA). By contrast, p-hydroxybenzoic acid (p-OH-BA) has virtually no effect on flowering at levels as high as 320 ..mu..M. Uptake rates for the three compounds are comparable. Competition studies using /sup 14/C-SA indicate that, compared to SA, BA is about 10-fold less effective and p-OH-BA is nearly 100-fold less effective in competing against /sup 14/C-SA uptake. Both the effectiveness of SA for inducing flowering and the uptake of /sup 14/C-SA are substantially increased as the pH of the medium is lowered from 8 to 4.5. Under a nitrogen atmosphere the uptake of /sup 14/C-SA is partially inhibited above pH 5. Phosphate metabolism may be important for flowering since increasing the phosphate level in the medium 10-15 fold results in substantial flowering, and suboptimal levels of Sa and phosphate interact synergistically to stimulate flowering. The interaction of phosphate with BA and p-OH-BA will be presented.

Cleland, F.C.; Kang, B.G.; Khurana, J.P.

1986-04-01

237

Augmenting the activity of antifungal agents against aspergilli using structural analogues of benzoic acid as chemosensitizing agents.  

PubMed

A number of benzoic acid analogues showed antifungal activity against strains of Aspergillus flavus, Aspergillus fumigatus and Aspergillus terreus, causative agents of human aspergillosis, in in vitro bioassays. Structure-activity analysis revealed that antifungal activities of benzoic and gallic acids were increased by addition of a methyl, methoxyl or chloro group at position 4 of the aromatic ring, or by esterification of the carboxylic acid with an alkyl group, respectively. Thymol, a natural phenolic compound, was a potent chemosensitizing agent when co-applied with the antifungal azole drugs fluconazole and ketoconazole. The thymol-azole drug combination demonstrated complete inhibition of fungal growth at dosages far lower than the drugs alone. Co-application of thymol with amphotericin B had an additive effect on all strains of aspergilli tested with the exception of two of three strains of A. terreus, where there was an antagonistic effect. Use of two mitogen-activated protein kinase (MAPK) mutants of A. fumigatus, sakA? and mpkC?, having gene deletions in the oxidative stress response pathway, indicated antifungal and/or chemosensitization activity of the benzo analogues was by disruption of the oxidative stress response system. Results showed that both these genes play overlapping roles in the MAPK system in this fungus. The potential of safe, natural compounds or analogues to serve as chemosensitizing agents to enhance efficacy of commercial antifungal agents is discussed. PMID:20943191

Kim, Jong H; Campbell, Bruce C; Mahoney, Noreen; Chan, Kathleen L; Molyneux, Russell J; Balajee, Arunmozhi

2010-08-06

238

Quantitative determination of hippuric and benzoic acids in urine by LC-MS/MS using surrogate standards.  

PubMed

An LC-MS/MS method for simultaneous determination of hippuric acid (HA) and benzoic acid (BA) in monkey urine after direct injection was developed. Since HA and BA are endogenous compounds in urine, surrogate standards ((13)C(6)-hippuric and (13)C(6)-benzoic acid) were employed to generate calibration curves. l-Phenylalanine-ring-D5 served as an internal standard. Multiple reaction monitoring in the negative ionization mode with an APCI source was used for detection of all components in the assay. The developed method is intended for determination of HA and BA in the range of 0.25-250 and 0.1-100microg/ml, respectively. Weighted (1/x) quadratic regression (r(2)>0.99) was used to generate calibration curves. Precision and accuracy of the method were assessed by analyzing 3 quality control samples (concentrations at low, medium, and high range of calibration curve) prepared in monkey urine. Stability for 48h at room temperature and after 3 freeze-thaw cycles was also evaluated. The proposed method was successfully utilized for analysis of urine samples from female monkeys following the administration of everninomicin alone and in combination with gentamicin. The concentrations of endogenous HA and BA were calculated based on the peak area ratio of the analyte to the internal standard using a regression equation for corresponding surrogate standard. PMID:20149566

Penner, Natalia; Ramanathan, Ragu; Zgoda-Pols, Joanna; Chowdhury, Swapan

2010-01-18

239

catena-Poly[[aqua-(benzoato-?O,O')(benzoic acid-?O)calcium]-?(3)-benzoato-?O:O,O':O'].  

PubMed

In title compound, [Ca(C(7)H(5)O(2))(2)(C(7)H(6)O(2))(H(2)O)](n), the eightfold-coordinated Ca(II) ion is bonded to four carboxyl-ate O atoms from two benzoate ions, an O atom from benzoic acid and a water O atom. One of the carboxyl-ate groups bridges adjacent Ca(2+) ions, forming a polymeric ribbon structure parallel to [010]. In the crystal, the benzoate anions and water mol-ecule inter-act by way of inter- and intra-molecular O-H?O hydrogen bonds. PMID:21754317

Azizov, Olimjon; Kadirova, Zukhra; Azizov, Tohir; Tolipov, Samat; Ibragimov, Bakhtiyar

2011-04-16

240

Effects of ionic liquid as additive and the pH of the mobile phase on the retention factors of amino benzoic acids in RP-HPLC.  

PubMed

As an organic salt, ionic liquids are widely used as new solvent media. In this paper, three positional isomers, such as o-amino benzoic acid, m-amino benzoic acid, and p-amino benzoic acid are separated with four different ionic liquids as additives to the mobile phase using reversed-phase (RP) high-performance liquid chromatography (HPLC). Amino benzoic acids are biologically active substances; the p-isomer is present in a group of water-soluble vitamins and is widely known as a sunscreen agent. The ionic liquids used are 1-butyl-3-methylimidazolium tetrafluoroborate, 1-ethyl-3-methylimidazolium tetrafluoroborate, 1-ethyl-3-methylimidazolium methylsulfate, and 1-octyl-3-methylimidazolium methylsulfate. The effects of the length of the alkyl group on the imidazolium ring and its counterion, the concentrations of the ionic liquid, and the effect of the pH of the mobile phase on the retention factor of the amino benzoic acid isomers are studied. Separation with the ionic liquid in the eluent was better than the separation without the ionic liquid. The pH mainly affected the retention and elution order of the solutes in RP-HPLC. PMID:17555633

Zheng, J; Polyakova, Y; Row, K H

241

[Study on photoluminescence of 2-(4-chloro-benzoyl)benzoic acid complexes].  

PubMed

Eight complexes of europium and terbium were synthesized, with 2-(4-chloro-benzoyl)benzoic acid as an essential ligand and other three distinct ligands, including 1, 10-phenanthroline, triphenylphosphine oxide and diphenyl sulfoxide, as selective ligands. They were Eu(CBBA)3 (H2O)4, Eu(CBBA)3 (Phen) (H2O)6, Eu(CBBA)3 (TPPO) (H2O)4, Eu(CBBA)3 (DPSO) (H2O)5, Tb(CBBA)3 (H2O)4, Tb(CBBA)3 (Phen)(H2O)3, Tb(CBBA)3(TPPO)(H2O)2 and Tb(CBBA)3 (DPSO)(H2O)4, respectively. Then their excitation and emission spectra were measured, and that how the central ions were differently impacted by the three second ligands was also compared. It was easily to be seen that from the spectra all the complexes luminesced with the similar special peaks. However, the luminescence intensity was evidently distinct, because 1, 10-phenanthroline, triphenylphosphine oxide and diphenyl sulfoxide were coordinated with them, and exerted different effects on transferring energy to the central ions. In the complexes of europium, Eu(CBBA) (Phen) (H2O) 6 and Eu(CBBA) (DPSO) (H2O) 5 each luminesced more strongly than Eu(CBBA)3 (H2O)4, however, Eu(CBBA)3(TPPO) (H2O)4 luminesced more weakly than Eu(CBBA)3 (H2O)4. Moreover, Eu(CBBA) (DPSO)(H2O)5 luminesced more intensely than Eu(CBBA)3 (Phen)(H2O)6. So 1,10-phenanthroline and diphenyl sulfoxide could sensitize the luminescence, whereas triphenylphosphine oxide could quench the luminescence in the certain Eu complexes. In Tb complexes, diphenyl sulfoxide sensitized the luminescence of Tb(CBBA)3 (DPSO)(H2O)4, and reversely, 1,10-phenanthroline and triphenylphosphine oxide quenched differently the luminescence of Tb(CBBA)3 (Phen)(H2O)3 and Tb(CBBA) (TPPO)(H2O)2. 1,10-phenanthroline quenched more strongly than triphenylphosphine. From IR spectra, the structure of the complexes was conjectured approximately. In the region of 3 200-3 600 cm(-1), there were some weak vibrant peaks owed to hydroxyl of water, a good proof that there were water molecules in the complexes themselves. PMID:20101950

Li, Zhao-Ye; Geng, Xiao-Tian; Wang, Juan; Zhao, Ying; Wu, Hong; Yan, Jian-Bo; Wang, Yun-You; Sun, Bo

2009-11-01

242

4-Aza-1-azoniabicyclo-[2.2.2]octa-ne-2-amino-benzoate-2-amino-benzoic acid (1/1/1)  

PubMed Central

A 4-aza-1-azoniabicyclo[2.2.2]octane cation, a 2-aminobenzoate anion and a neutral 2-aminobenzoic acid molecule comprise the asymmetric unit of the title compound, C6H13N2 +C7H6NO2 ?C7H7NO2. An intramolecular NH?O hydrogen bond occurs in the anion and in the neutral 2-aminobenzoic acid molecule. The cation provides a charge-assisted NH?O hydrogen bond to the anion, and the 2-aminobenzoic acid molecule forms an OH?N hydrogen bond to the unprotonated amino N atom in the cation. In this way, a three-component aggregate is formed. These are connected into a three-dimensional network by aminocarboxylate NH?O hydrogen bonds. NH?N hydrogen bonds are also observed.

Arman, Hadi D.; Kaulgud, Trupta; Tiekink, Edward R. T.

2011-01-01

243

Photocatalytic degradation of formic and benzoic acids and hydrogen peroxide evolution in TiO 2 and ZnO water suspensions  

Microsoft Academic Search

The photocatalytic degradation of formic acid (FA) and benzoic acid (BA), chosen as model organic molecules with acidic properties, was investigated in TiO2 and ZnO water suspensions under different experimental conditions. Hydrogen peroxide evolution, formed through a reductive pathway started by conduction band electrons, was also simultaneously monitored during the degradation runs. The effect of different initial amounts of substrates

Marta Mrowetz; Elena Selli

2006-01-01

244

In situ synthesis of terbium-benzoic acid complex in solgel derived silica by a two-step solgel method  

Microsoft Academic Search

Terbium complexes with benzoic acid and its derivatives o-hydroxybenzoic acid and p-hydroxybenzoic acid were in situ synthesized in solgel derived silica matrix via a two-step solgel process. The formation process of the complex was characterized by fluorescence spectra, absorption spectra and IR spectra. The gels that contain in situ synthesized complexes exhibit the characteristic emission bands of terbium ion. The

F. Lianshe; Meng Qingguo; Zhang Hongjie; Wang Shubin; Yang Kuiyue; N. Jiazuan

2000-01-01

245

Excitonic splitting and coherent electronic energy transfer in the gas-phase benzoic acid dimer  

SciTech Connect

The benzoic acid dimer, (BZA){sub 2}, is a paradigmatic symmetric hydrogen bonded dimer with two strong antiparallel hydrogen bonds. The excitonic S{sub 1}/S{sub 2} state splitting and coherent electronic energy transfer within supersonically cooled (BZA){sub 2} and its {sup 13}C-, d{sub 1}-, d{sub 2}-, and {sup 13}C/d{sub 1}- isotopomers have been investigated by mass-resolved two-color resonant two-photon ionization spectroscopy. The (BZA){sub 2}-(h-h) and (BZA){sub 2}-(d-d) dimers are C{sub 2h} symmetric, hence only the S{sub 2} Leftwards-Arrow S{sub 0} transition can be observed, the S{sub 1} Leftwards-Arrow S{sub 0} transition being strictly electric-dipole forbidden. A single {sup 12}C/{sup 13}C or H/D isotopic substitution reduces the symmetry of the dimer to C{sub s}, so that the isotopic heterodimers (BZA){sub 2}-{sup 13}C, (BZA){sub 2}-(h-d), (BZA){sub 2}-(h{sup 13}C-d), and (BZA){sub 2}-(h-d{sup 13}C) show both S{sub 1} Leftwards-Arrow S{sub 0} and S{sub 2} Leftwards-Arrow S{sub 0} bands. The S{sub 1}/S{sub 2} exciton splitting inferred is {Delta}{sub exc}= 0.94 {+-} 0.1 cm{sup -1}. This is the smallest splitting observed so far for any H-bonded gas-phase dimer. Additional isotope-dependent contributions to the splittings, {Delta}{sub iso}, arise from the change of the zero-point vibrational energy upon electronic excitation and range from {Delta}{sub iso}= 3.3 cm{sup -1} upon {sup 12}C/{sup 13}C substitution to 14.8 cm{sup -1} for carboxy H/D substitution. The degree of excitonic localization/delocalization can be sensitively measured via the relative intensities of the S{sub 1} Leftwards-Arrow S{sub 0} and S{sub 2} Leftwards-Arrow S{sub 0} origin bands; near-complete localization is observed even for a single {sup 12}C/{sup 13}C substitution. The S{sub 1}/ S{sub 2} energy gap of (BZA){sub 2} is {Delta}{sub calc}{sup exc}=11 cm{sup -1} when calculated by the approximate second-order perturbation theory (CC2) method. Upon correction for vibronic quenching, this decreases to {Delta}{sub vibron}{sup exc}=2.1 cm{sup -1} [P. Ottiger et al., J. Chem. Phys. 136, 174308 (2012)], in good agreement with the observed {Delta}{sub exc}= 0.94 cm{sup -1}. The observed excitonic splittings can be converted to exciton hopping times {tau}{sub exc}. For the (BZA){sub 2}-(h-h) homodimer {tau}{sub exc}= 18 ps, which is nearly 40 times shorter than the double proton transfer time of (BZA){sub 2} in its excited state [Kalkman et al., ChemPhysChem 9, 1788 (2008)]. Thus, the electronic energy transfer is much faster than the proton-transfer in (BZA){sub 2}{sup *}.

Ottiger, Philipp; Leutwyler, Samuel [Departement fuer Chemie und Biochemie, Universitaet Bern, Freiestrasse 3, CH-3012 Bern (Switzerland)

2012-11-28

246

Synthesis and antiradical/antioxidant activities of caffeic acid phenethyl ester and its related propionic, acetic, and benzoic acid analogues.  

PubMed

Caffeic acid phenethyl ester (CAPE) is a bioactive component isolated from propolis. A series of CAPE analogues was synthesized and their antiradical/antioxidant effects analyzed. The effect of the presence of the double bond and of the conjugated system on the antioxidant effect is evaluated with the analogues obtained from 3-(3,4-dihydroxyphenyl) propanoic acid. Those obtained from 2-(3,4-dihydroxyphenyl) acetic acid and 3,4-dihydroxybenzoic acid allow the evaluation of the effect of the presence of two carbons between the carbonyl and aromatic system. PMID:23222926

LeBlanc, Luc M; Par, Aurlie F; Jean-Franois, Jacques; Hbert, Martin J G; Surette, Marc E; Touaibia, Mohamed

2012-12-10

247

Proton tunnelling in the hydrogen bonds of halogen-substituted derivatives of benzoic acid studied by NMR relaxometry: the case of large energy asymmetry  

NASA Astrophysics Data System (ADS)

The concerted two proton transfer in the hydrogen bonds of para-halogen substituted derivatives of benzoic acid has been investigated using conventional NMR relaxometry combined with field-cycling measurements of the magnetic field dependence of the proton spin-lattice relaxation rate. Thus, the inverse correlation time describing the proton transfer process has been determined over a wide range of temperature. The energy difference between the two proton configurations was determined in all four compounds to be significantly larger than in the prototype model system of benzoic acid dimers. This energy difference exceeds the cut-off frequency of the acoustic phonon spectrum of the crystal as well as the frequency of two lowest modes promoting proton tunnelling. The low temperature limit of the tunnelling rate was found to be one order of magnitude higher than in benzoic acid. For the four compounds studied, this rate and its increase at higher temperature exhibit a different behaviour to benzoic acid which is attributed to the details of the level structure and energy gaps between states corresponding predominantly to one or the other proton configuration. A new adaptation of the phonon-assisted theory is proposed which applies to these cases of high energy asymmetry. To assist in the interpretation of the data, a powder neutron diffraction structure determination of 4-bromobenzoic acid is reported together with DFT calculations on the hydrogen bond structures of all members of the 4-halogen substituted derivatives.

Horsewill, A. J.; McGloin, C. J.; Trommsdorff, H. P.; Johnson, M. R.

2003-06-01

248

Crystal engineering approach to forming cocrystals of amine hydrochlorides with organic acids. Molecular complexes of fluoxetine hydrochloride with benzoic, succinic, and fumaric acids.  

PubMed

A crystal engineering strategy for designing cocrystals of pharmaceuticals is presented. The strategy increases the probability of discovering useful cocrystals and decreases the number of experiments that are needed by selecting API:guest combinations that have the greatest potential of forming energetically and structurally robust interactions. Our approach involves multicomponent cocrystallization of hydrochloride salts, wherein strong hydrogen bond donors are introduced to interact with chloride ions that are underutilized as hydrogen bond acceptors. The strategy is particularly effective in producing cocrystals of amine hydrochlorides with neutral organic acid guests. As an example of the approach, we report the discovery of three cocrystals containing fluoxetine hydrochloride (1), which is the active ingredient in the popular antidepressant Prozac. A 1:1 cocrystal was prepared with 1 and benzoic acid (2), while succinic acid and fumaric acid were each cocrystallized with 1 to provide 2:1 cocrystals of fluoxetine hydrochloride:succinic acid (3) and fluoxetine hydrochloride:fumaric acid (4). The presence of a guest molecule along with fluoxetine hydrochloride in the same crystal structure results in a solid phase with altered physical properties when compared to the known crystalline form of fluoxetine hydrochloride. On the basis of intrinsic dissolution rate experiments, cocrystals 2 and 4 dissolve more slowly than 1, and 3 dissolves more quickly than 1. Powder dissolution experiments demonstrated that the solid present at equilibrium corresponds to the cocrystal for 2 and 4, while 3 completely converted to 1 upon prolonged slurry in water. PMID:15479089

Childs, Scott L; Chyall, Leonard J; Dunlap, Jeanette T; Smolenskaya, Valeriya N; Stahly, Barbara C; Stahly, G Patrick

2004-10-20

249

Influence of bleaching on flavor of 34% whey protein concentrate and residual benzoic acid concentration in dried whey proteins.  

PubMed

Previous studies have shown that bleaching negatively affects the flavor of 70% whey protein concentrate (WPC70), but bleaching effects on lower-protein products have not been established. Benzoyl peroxide (BP), a whey bleaching agent, degrades to benzoic acid (BA) and may elevate BA concentrations in dried whey products. No legal limit exists in the United States for BP use in whey, but international concerns exist. The objectives of this study were to determine the effect of hydrogen peroxide (HP) or BP bleaching on the flavor of 34% WPC (WPC34) and to evaluate residual BA in commercial and experimental WPC bleached with and without BP. Cheddar whey was manufactured in duplicate. Pasteurized fat-separated whey was subjected to hot bleaching with either HP at 500 mg/kg, BP at 50 or 100 mg/kg, or no bleach. Whey was ultrafiltered and spray dried into WPC34. Color [L*(lightness), a* (red-green), and b* (yellow-blue)] measurements and norbixin extractions were conducted to compare bleaching efficacy. Descriptive sensory and instrumental volatile analyses were used to evaluate bleaching effects on flavor. Benzoic acid was extracted from experimental and commercial WPC34 and 80% WPC (WPC80) and quantified by HPLC. The b* value and norbixin concentration of BP-bleached WPC34 were lower than HP-bleached and control WPC34. Hydrogen peroxide-bleached WPC34 displayed higher cardboard flavor and had higher volatile lipid oxidation products than BP-bleached or control WPC34. Benzoyl peroxide-bleached WPC34 had higher BA concentrations than unbleached and HP-bleached WPC34 and BA concentrations were also higher in BP-bleached WPC80 compared with unbleached and HP-bleached WPC80, with smaller differences than those observed in WPC34. Benzoic acid extraction from permeate showed that WPC80 permeate contained more BA than did WPC34 permeate. Benzoyl peroxide is more effective in color removal of whey and results in fewer flavor side effects compared with HP and residual BA is decreased by ultrafiltration and diafiltration. PMID:21854907

Listiyani, M A D; Campbell, R E; Miracle, R E; Dean, L O; Drake, M A

2011-09-01

250

Tailoring band gaps of insulators by adsorption at surface defects: Benzoic acids on NaCl surfaces  

NASA Astrophysics Data System (ADS)

The adsorption of benzoic acid and its OH-substituted derivatives, namely, salicylic acid (SA) and parasalicylic acid on various NaCl surfaces has been investigated by density-functional theory with hybrid exchange-correlation functional. The ideal NaCl(100) surface is chemically inert as evidenced by the low binding energies. The molecular adsorption can be enhanced by both an anion vacancy and a surface step site. The bonding between the surface Na and the carboxylic O atom is of covalent character for all adsorption geometries. Our calculations show that the adsorption of SA has the largest binding energy of all three acids due to the additional interaction between Na and the phenolic O atom. Charge transfer between the molecule and the surface is generally very small, except in the presence of an anion vacancy where the unpaired electron is mostly transferred to the adsorbate. Surface defects generally have a strong influence on the electronic structure of the adsorbed molecules. Specifically, the adsorption of SA at [011]-oriented steps can significantly reduce the effective band gap to 1.6 eV due to the up shift of the Cl3p levels at the undercoordinated step edge. Implications of these results to the contact charging effect between wide-band-gap insulators will be discussed.

Chen, Wei; Tegenkamp, Christoph; Pfnr, Herbert; Bredow, Thomas

2009-06-01

251

Fermented vegetables containing benzoic and ascorbic acids as additives: benzene formation during storage and impact of additives on quality parameters.  

PubMed

Chemical and sensorial changes related to the use of benzoates and ascorbic acid as additives in packed fermented vegetables were investigated. For this, three selected vegetables (green olives, cucumbers, and caperberries) stored under different conditions (glass or plastic containers, ambient or refrigerated storage) were used. In all cases, benzoic acid remained unchanged (glass bottle) or decreased slightly (plastic pouch) at prolonged storage. Ascorbic acid was partially or totally degraded during storage, the degradation rate depending on the storage conditions and the vegetable matrix. Benzene levels higher than 10 ?g/L were found in cucumbers and caperberries containing both additives, but only when packed in plastic pouches and after prolonged storage at room temperature. In these conditions, an appreciable browning of brine, related to AA degradation, was also found. The use of benzoate alone had a significant influence on vegetable color, but flavor was not significantly affected at the benzoate levels tested. On the basis of the present study, benzoates should be removed from fermented vegetable formulations containing ascorbic acid to eliminate possible benzene formation during long-term storage. PMID:21361339

Casado, Francisco Javier; Snchez, Antonio Higinio; De Castro, Antonio; Rejano, Luis; Beato, Vctor Manuel; Montao, Alfredo

2011-03-01

252

Field-Based Stable Isotope Probing Reveals the Identities of Benzoic Acid-Metabolizing Microorganisms and Their In Situ Growth in Agricultural Soil?  

PubMed Central

We used a combination of stable isotope probing (SIP), gas chromatography-mass spectrometry-based respiration, isolation/cultivation, and quantitative PCR procedures to discover the identity and in situ growth of soil microorganisms that metabolize benzoic acid. We added [13C]benzoic acid or [12C]benzoic acid (100 ?g) once, four times, or five times at 2-day intervals to agricultural field plots. After monitoring 13CO2 evolution from the benzoic acid-dosed soil, field soils were harvested and used for nucleic acid extraction and for cultivation of benzoate-degrading bacteria. Exposure of soil to benzoate increased the number of culturable benzoate degraders compared to unamended soil, and exposure to benzoate shifted the dominant culturable benzoate degraders from Pseudomonas species to Burkholderia species. Isopycnic separation of heavy [13C]DNA from the unlabeled fraction allowed terminal restriction fragment length polymorphism (T-RFLP) analyses to confirm that distinct 16S rRNA genes were localized in the heavy fraction. Phylogenetic analysis of sequenced 16S rRNA genes revealed a predominance (15 of 58 clones) of Burkholderia species in the heavy fraction. Burkholderia sp. strain EBA09 shared 99.5% 16S rRNA sequence similarity with a group of clones representing the dominant RFLP pattern, and the T-RFLP fragment for strain EBA09 and a clone from that cluster matched the fragment enriched in the [13C]DNA fraction. Growth of the population represented by EBA09 during the field-dosing experiment was demonstrated by using most-probable-number-PCR and primers targeting EBA09 and the closely related species Burkholderia hospita. Thus, the target population identified by SIP not only actively metabolized benzoic acid but reproduced in the field upon the addition of the substrate.

Pumphrey, Graham M.; Madsen, Eugene L.

2008-01-01

253

Enzymatic synthesis of 4-OH-benzoic acid from phenol and CO 2: the first example of a biotechnological application of a Carboxylase enzyme  

Microsoft Academic Search

4-OH benzoic acid has been synthesized from phenol and CO2 at room temperature and sub-atmospheric pressure of CO2 with 100 % selectivity, using a Carboxylase enzyme. A cheap, fast and easy method for the phosphorylation of phenol has been also developed.This represents the first biotechnological application of a Carboxylase enzyme.

Michele Aresta; Eugenio Quaranta; Roberto Liberio; Caterina Dileo; Immacolata Tommasi

1998-01-01

254

Iron catalyzed competitive olefin oxidation and ipso-hydroxylation of benzoic acids: further evidence for an Fe(V)?O oxidant.  

PubMed

The iron complex [Fe(II)(TPA)(CH(3)CN)(2)](OTf)(2) (1) [TPA = tris(2-pyridylmethyl)amine] with H(2)O(2) as an oxidant performs ipso-hydroxylation of electron-withdrawing benzoic acids at room temperature, leading to multiple turnovers of corresponding phenols. ipso-Hydroxylation competes with olefin epoxidation and cis-dihydroxylation in the presence of olefins, with the product ratios being modulated by the relative amounts of benzoic acid, olefin, and water. It is proposed that benzoic acid and water compete for the available sixth site on the [(TPA)Fe(III)(OOH)] intermediate, which undergoes O-O bond heterolysis to form, respectively, the Fe(V)(O)(O(2)CAr) and Fe(V)(O)(OH) oxidants that determine the product outcome. The putative Fe(V)(O)(O(2)CAr) oxidant decays either by undergoing oxidative decarboxylation and subsequent ipso-hydroxylation to form the observed phenol product or by oxo-transfer to olefins to form epoxide. The observed higher yield of phenol over epoxide or cis-diol in all cases studied, where an electron-withdrawing benzoic acid is present in the reaction mixture, suggests that intramolecular decay of the putative Fe(V)(O)(O(2)CAr) oxidant is favored over intermolecular olefin oxidation. These results support the mechanistic framework postulated for Fe(TPA) oxidative catalysis and further strengthens the notion that oxoiron(V) species are the key oxidants in these reactions. PMID:20866083

Das, Parthapratim; Que, Lawrence

2010-10-18

255

Effects of a reduced calcium, phosphorus and protein intake and of benzoic acid on calcium and phosphorus metabolism of growing pigs  

Microsoft Academic Search

In order to minimise environmental pollution, many pig feeds contain low phosphorus and protein concentrations as well as benzoic acid (BA), an additive which reduces ammonia formation in the slurry. Since both a low P intake and metabolic acidosis compromise bone mineralisation, the effect of a diet with a low concentration of calcium (Ca), phosphorus (P) and crude protein (CP)

A. Gutzwiller; H. D. Hess; A. Adam; D. Guggisberg; A. Liesegang; P. Stoll

2011-01-01

256

40 CFR 721.10020 - Benzoic acid, 5-amino-2-chloro-, 1,1-dimethyl-2-oxo-2-(2-propenyloxy) ethyl ester.  

Code of Federal Regulations, 2013 CFR

. (1) The chemical substance identified as benzoic acid, 5-amino-2-chloro-, 1,1-dimethyl-2-oxo-2-(2-propenyloxy) ethyl ester (PMN P-01-564; CAS No. 174489-43-1) is subject to reporting under this section for the significant new uses described in paragraph (a)(2) of this...

2013-07-01

257

Optical dephasing by uncorrelated phonon scattering to librations. An optical and picosecond photon echo study of a photosite of pentacene in benzoic acid  

Microsoft Academic Search

We report results of an optical and picosecond photon echo study on the zero-phonon line of photosite I of pentacene in benzoic acid. The results show that optical dephasing in this system proceeds via uncorrelated phonon scattering processes from the ground and optically excited state to singly excited librational levels. It is also shown that the data can not be

Laurens W. Molenkamp; Douwe A. Wiersma

1984-01-01

258

Intermolecular and Intramolecular Radiationless Processes in pTerphenyl and Benzoic-Acid Single Crystals Doped with Tetra-Cene or Pentacene  

Microsoft Academic Search

Singlet excitation energy transfer processes and inter-system crossing in the mixed crystalline systems, p-terphenyl: :tetracene, p-terphenyl:pentacene and benzoic acid:pentacene were investigated in the temperature range 2 - 300 K using stationary fluorescence spectroscopy.

Carola Kryschi; Arnd Krger; Birgit Wagner; Wolfgang Gorgas

1992-01-01

259

Gas phase substitution reactions by radical cations. Part 2. Reaction of the CC ring-opened oxirane radical cation with benzonitrile and benzoic acid  

Microsoft Academic Search

Under conditions of chemical ionization in the high pressure source of a mass spectrometer, the C---C ring-opened oxirane radical cation transfers a methylene group to benzonitrile and benzoic acid. This transfer reaction leads to the formation of [M + 14][radical sign]+ product ions. The structures of these ions have been established by collisionally induced dissociation of these ions compared with

C. G. de Koster; J. J. van Houte; J. van Thuijl

1993-01-01

260

Effect of 2-Hydroxy-4-Methoxy Benzoic Acid from the Roots of Hemidesmus indicus on Streptozotocin-induced Diabetic Rats  

PubMed Central

The aim of the present study was to investigate the effect of 2-hydroxy-4-methoxy benzoic acid isolated from the roots of Hemidesmus indicus on plasma glucose, plasma, erythrocyte and erythrocyte membrane lipid peroxidation and membrane-bound Ca2+ ATPase activity in streptozotocin-induced diabetic rats. In our study, diabetic rats had increased levels of blood glucose and lipid peroxidation in plasma, erythrocytes and erythrocyte membrane and decreased level of plasma insulin and decreased activity of low affinity Ca2+ ATPase in erythrocytes. Restoration of plasma insulin and glucose in diabetic rats indicates the effect of HMBA on insulin, glucose and lipid peroxidation. HMBA also restored diabetes-induced alterations in the activity of membrane-bound Ca2+ ATPase. Based on the results of this study it can be concluded that HMBA mediated normalization of membrane-bound ATPase in erythrocytes is due to improved glycemic control and antioxidant activity.

Gayathri, M.; Kannabiran, K.

2009-01-01

261

The mechanism of singlet to triplet transitions of pentacene guests in p-terphenyl and benzoic acid crystals  

NASA Astrophysics Data System (ADS)

In this paper we examine the effect of the different site configurations on the S 1?T 1 intersystem crossin (ISC) of pentacene in p-terphenyl (ptp) and benzoic acid (bza) crystals by measuring site-selectively the fluorescence quantum yield of pentacene as function of temperature in the range 4.2-140 K. The local structures of the four sites (O 1, O 2, O 3, O 4) for pentacene in ptp are simulated using the Buckingham (exp-6) potential. The present study provides a rationalization for the temperature dependent ISC rates of pentacene at O 1 and O 2 in ptp and pentacene in bza as well as for the enhanced, temperature independent ISC rates of pentancene at O 3 and O 4 in ptp.

Kryschi, Carola; Fleischhauer, H.-C.; Wagner, Birgit

1992-04-01

262

Spectroscopic determination of enthalpies of sublimation of organic materials in the vapor phase: Benzoic acid, ferrocene, and naphthalene  

NASA Astrophysics Data System (ADS)

Techniques for determining the enthalpies of sublimation of low volatile materials in the vapor phase are quite rare. Although benzoic acid, ferrocene, and naphthalene are used as reference materials for indirect determination of vapor pressure of volatile materials, the discrepancy of the values of their enthalpies of sublimation is considerably large (10-15 kJ/mol). In this work, the enthalpies of sublimation of vapors of these materials are determined using absorbance spectroscopy in the ultraviolet region of the electromagnetic spectrum. This methodology is based on the linear proportionality between the density of the saturated gas of the material and the absorbance of the gas. The determined values of enthalpies of sublimation are in excellent agreement with the mean value of those reported in literature and those recommended by the ICTAC. This method is shown to be accurate and rapid.

Hikal, Walid M.; Weeks, Brandon L.

2013-03-01

263

Binding of 2-(4'-hydroxyphenylazo)benzoic acid to bovine serum albumin characterized by optical spectroscopy and equilibrium dialysis.  

PubMed

Binding of 2-(4'-hydroxyphenylazo)benzoic acid (HABA) to bovine serum albumin (BSA) was studied by equilibrium dialysis, by the spectrophotometric method and by the absorption spectra of bound HABA. Comparison of equilibrium dialysis with the spectrophotometric method clarified the presence of a undisclosed class of binding sites, which do not cause the spectral change at about 480 nm to HABA, on BSA. Two bands observed on the absorption spectra of bound HABA were attributed to differently perturbed two HABA molecules by BSA, the azo and hydrazone forms, and these two forms correspond to HABA molecules bound to non-metachromasy sites and metachromasy sites, respectively. The concentration of each from was calculated by using estimated molar extinction coefficient. PMID:7277193

Sakurai, T; Tsuchiya, S; Matsumaru, H

1981-01-01

264

2-{[1-(3,4Dihydroxyphenyl)methylidene]amino}benzoic acid immobilized Amberlite XAD-16 as metal extractant  

Microsoft Academic Search

2-{[1-(3,4-Dihydroxyphenyl)methylidene]amino}benzoic acid (DMABA) was loaded on Amberlite XAD-16 (AXAD-16) via azo linker and the resulting resin AXAD-16-DMABA explored for enrichment of Zn(II), Mn(II), Ni(II), Pb(II), Cd(II), Cu(II), Fe(III) and Co(II). The optimum pH values for extraction are 6.57.0, 5.06.0, 5.57.5, 5.06.5, 6.58.0, 5.57.0, 4.05.0 and 6.07.0, respectively. The sorption capacity was found between 97 and 515?molg?1 and the preconcentration factors

Gopalan Venkatesh; Ajai K. Singh

2005-01-01

265

Proteomic and metabolomic analyses of the white-rot fungus Phanerochaete chrysosporium exposed to exogenous benzoic acid.  

PubMed

Intracellular processes of the white-rot basidiomycete Phanerochaete chrysosporium involved in the metabolism of benzoic acid (BA) were investigated at the proteome and metabolome level. Up-regulation of aryl-alcohol dehydrogenase, arylaldehyde dehydrogenase, and cytochrome P450s was observed upon addition of exogenous BA, suggesting that these enzymes play key roles in its metabolism. Intracellular metabolic shifts from the short-cut TCA/glyoxylate bicycle system to the TCA cycle and an increased flux in the TCA cycle indicated activation of the heme biosynthetic pathway and the production of NAD(P)H. In addition, combined analyses of proteome and metabolome clearly indicated the role of trehalose as a storage disaccharide and that the mannitol cycle plays a role in an alternative energy-producing pathway. PMID:18435559

Matsuzaki, Fumiko; Shimizu, Motoyuki; Wariishi, Hiroyuki

2008-04-25

266

o-Alkylselenenylated benzoic acid accesses several sites in serum albumin according to fluorescence studies, Raman spectroscopy and theoretical simulations.  

PubMed

In the circulatory system, serum albumin (SA) is an important transporter of the majority of molecules with biological activity. We focused the current study on the anti-inflammatory compound, o-alkylselenenylated benzoic acid (ALKSEBEA), to determine its ability to access SA. Herein, we employed experimental procedures (fluorescence studies, Raman spectroscopy) and docking study on SA obtained from the Protein Data Bank and key conformers obtained from molecular dynamics simulations. The results show that ALKSEBEA accesses SA using a cooperative behavior according to fluorescence studies. In addition, the Raman results indicate that the ligand binding affects the backbone constituents. These results were confirmed by docking simulations tested on several SA conformers, which showed that ALKSEBEA bound on several sites on SA via ?-? or ?-cation interactions and that the ligand reaches other binding sites, where aromatic and basic residues as well as the backbone residues are involved. PMID:22973844

Martinez-Ramos, Federico; Fonseca-Sabater, Yadira; Soriano-Ursa, Marvin A; Torres, Eduardo; Rosales-Hernndez, Martha C; Trujillo-Ferrara, Jos G; Tolentino-Lopez, Luis E; Ilizaliturri-Flores, Ian; Correa-Basurto, Jos

2013-06-01

267

Crystal structure of complexes of bivalent Co, Ni, and Cd with anions of benzoic and 2-(acetylamino)-5-nitrobenzoic acids  

NASA Astrophysics Data System (ADS)

The structure of three complexes of bivalent metals (cobalt, nickel, and cadmium) with anions of benzoic (H L 1) and 2-(acetylamino)-5-nitrobenzoic (H L 2) acids, namely, [Co{2/1} (H2O)2(?-C4H4N2)] n ( I), [NiL2(H2O)5]L2 2H2O ( II), and [Cd(?- L 2)2(H2O)2] n 2 nH2O ( III), is determined. In chainlike structure I, cobalt atoms are connected by bridging pyrazine molecules; structure II contains isolated complexes. In structure III, centrosymmetric (CdOCO)2 cycles and polymeric ribbons are formed due to the coordination of the carboxylate group of the L 2 ligand to two cadmium atoms.

Rzaeva, M. F.; Askerov, R. K.; Movsumov, E. M.; Sergienko, V. S.; Ilyukhin, A. B.

2012-03-01

268

Substrate effects on the surface-enhanced Raman spectrum of benzoic acid adsorbed on silver oblate microparticles  

SciTech Connect

The effects of the local dielectric environment on the surface-enhanced Raman-scattering enhancement factor of benzoic acid adsorbed on silver oblate spheroids are studied experimentally and modeled theoretically. Silver-island films were annealed to produce spheroidal-shaped particles which exhibit well resolved resonances in absorption spectra. These resonances are shifted in different amounts by the depolarizing interaction with the substrate. An additional dielectric film has been deposited between the particles and substrate in order to measure the effects of proximity on the surface-enhanced Raman signal. Experimental observations on germanium and silicon are presented and found to be in agreement with calculations involving only the surface-plasmon excitation on the particles.

Goudonnet, J.P.; Bijeon, J.L.; Warmack, R.J.; Ferrell, T.L. (Health and Safety Research Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (US))

1991-02-15

269

Synthesis and Luminescence Properties of Two Novel Lanthanide (III) Perchlorate Complexes with Bis(benzoylmethyl) Sulfoxide and Benzoic Acid  

Microsoft Academic Search

Two novel ternary rare earth complexes of Tb(III) and Dy(III) perchlorates with bis(benzoylmethyl) sulfoxide (L) and benzoic\\u000a acid (L?) had been synthesized and characterized by elemental analysis, coordination titration analysis, molar conductivity,\\u000a IR, TG-DSC, 1HNMR and UV spectra. The results indicated that the composition of these complexes was REL5L?(ClO4)2nH2O (RE= Tb(III), Dy(III); L=C6H5COCH2SOCH2COC6H5, L?=C6H5COO; n?=?6,8). The fluorescence spectra illustrated that

Wen-Xian Li; Wen-Juan Chai; Xiao-Jun Sun; Tie Ren; Xiao-Yan Shi

2010-01-01

270

Purification and characterization of a novel catechol 1,2-dioxygenase from Pseudomonas aeruginosa with benzoic acid as a carbon source  

Microsoft Academic Search

Pseudomonas aeruginosa TKU002, capable of growing significantly on acidic side pH 5.5 and benzoic acid as a sole carbon source, was isolated from enrichment culture accumulation of catechol. An intracellular catechol 1,2-dioxygenase (CD) produced by P. aeruginosa TKU002 was purified and characterized. The TKU002 CD was found to have unique characteristics different to other microbial CDs. The unique characteristics include

Chuan-Lu Wang; Su-Lin You; San-Lang Wang

2006-01-01

271

Catalytic synthesis of benzoic esters with carbon-based solid acid from coal tar  

Microsoft Academic Search

A new carbon-based solid acid catalyst (C- SO3H) was prepared by simultaneous cross- linking coal tar with benzaldehyde,hoist temperature -curing ,sulphonation in sulfuric acid and was characterized by FT-IR,TG-DTG,XRD and neutralization potentiometric titration, and SEM techniques. The results indicated that there is the high density of SO3H groups in forming amorphous coke consisting of polycyclic aromatic carbon sheets, and the

Haie Hao; Baojun Ma; Jinxin Ma; Sun Yuan; Wanyi Liu

2011-01-01

272

Growth, thermal, dielectric and mechanical properties of L-phenylalanine-benzoic acid: A nonlinear optical single crystal  

NASA Astrophysics Data System (ADS)

An efficient amino acid family nonlinear optical single crystal L-phenylalanine-benzoic acid (LPB) was conveniently grown by slow evaporation technique at room temperature. The crystal system and the lattice parameters were analyzed by single crystal X-ray diffraction studies. The grown crystal has excellent transmission in the entire visible region and its lower cut-off wavelength was found to be 248 nm. The SHG efficiency of the grown crystal was found to be 1.6 times higher than that of KDP crystal. The Laser damage threshold value of LPB has been found to be 6.5 GW/cm2. The sample was thermally stable up to 134 C. Microhardness, dielectric and AC/DC conductivity measurements were made along (0 0 1) plane and reported for the first time. Microhardness studies revealed that the sample belongs to hard nature. Frequency dependent dielectric constant was measured for different temperatures and found maximum dielectric constant of 14 for 363 K. Photoconductivity studies of LPB divulged its negative photoconducting nature.

Tamilselvan, S.; Vimalan, M.; Vetha Potheher, I.; Rajasekar, S.; Jeyasekaran, R.; Antony Arockiaraj, M.; Madhavan, J.

2013-10-01

273

Modification of Chloride Ion Transport in Human Erythrocyte Ghost Membranes by Photoaffinity Labeling Reagents Based on the Structure of 5Nitro2-(3-Phenylpropylamino)-benzoic Acid (NPPB)  

Microsoft Academic Search

Using human red blood cell ghost membranes, we have evaluated 5-nitro-2-[N-3-(4-azidophenyl)-propylamino]-benzoic acid and 5-nitro-2-[N-3-(4-azido-2,3,5,6-tetrafluorophenyl)-propylamino]-benzoic acid (FAzNPPB) as photoaffinity labeling agents based on the structure of the widely important Cl? channel blocker 5-nitro-2-(3-phenylpropyl-amino)-benzoic acid (NPPB). The tetrafluoro-substituted aryl azide was found to be a more effective photoinactivating agent than the corresponding protio compound. Using a tritiated version ([3H]FAzNPPB), we demonstrated that

B. R. Branchini; M. H. Murtiashaw; E. A. Eckman; L. A. Egan; C. V. Alfano; J. G. Stroh

1995-01-01

274

A third monoclinic polymorph of 3,4,5-trihy-droxy-benzoic acid monohydrate  

PubMed Central

The title compound, C7H6O5H2O, is a new polymorph of the structures reported by Jiang et al. (2000 ?) [Acta Cryst. C56, 594595] and Okabe et al. (2001 ?) [Acta Cryst. E57, o764o766]. The gallic acid molecule is essentially planar (r.m.s. deviation = 0.550?). An intramolecular OH?O hydrogen bond occurs in the gallic acid molecule, which is linked to the water molecule by a further OH?O hydrogen bond. In the crystal, the components are linked by OH?O hydrogen bonds. The hydrogen-bonding pattern differs from those reported for the previous polymorphs.

Demirtas, Gunes; Dege, Necmi; Buyukgungor, Orhan

2011-01-01

275

3-[2-Chloro-4-(trifluoro-meth-yl)phen-oxy]benzoic acid.  

PubMed

The asymmetric unit of the title compound, C(14)H(8)ClF(3)O(3), comprises two independent mol-ecules. The rings in each molecule are connected together via O-H?O hydrogen bonds to form classical hydrogen-bonded carb-oxy-lic acid dimers. The dihedral angles between the benzene rings are 80.7?(1) and 68.7?(1). PMID:22220060

Liu, Yan-Ju; Liu, Jie

2011-10-29

276

Degradation of chloro- and methyl-substituted benzoic acids by a genetically modified microorganism.  

PubMed

Degradation of 3-chlorobenzoic acid (3CB), 4-chlorobenzoic acid (4CB), and 4-methylbenzoic acid (4MB) as single substrates (carbon sources) and as a substrate mixture were studied in batch and continuous culture using the genetically modified microorganism Pseudomonas sp. B13 FR1 SN45P. The strain was able to mineralize the single compounds as well as the substrate mixture completely. Conversion of the three compounds in the substrate mixture proceeded simultaneously. Maximum specific substrate conversion rates were calculated to be 0.9 g g(-1) h(-1) for 3 CB and 4CB and 1.1 g g(-1) h(-1) for 4MB. Mass balances indicated the transient accumulation of pathway intermediates during batch cultivations. Hence, the rate limiting step in the degradative pathway is not the initial microbial attack of the original substrate or its transport through the cell membrane. Degradation rates on 3CB were comparable to those of the parent strain Pseudomonas sp. B13. The stability of the degradation pathways of strain Pseudomonas sp. B13 FR1 SN45P could be demonstrated in a continuous cultivation over 3.5 months (734 generation times) on 3CB, 4MB, and 4CB, which were used as single carbon sources one after the other. PMID:18629816

Mller, R; Deckwer, W D; Hecht, V

1996-09-01

277

Degradation of chloro- and methyl-substituted benzoic acids by a genetically modified microorganism  

SciTech Connect

Degradation of 3-chlorobenzoic acid (3CB), 4-chlorobenzoic acid (4CB), and 4-methylbenzoic acid (4MB) as single substrates (carbon sources) and as a substrate mixture were studied in batch and continuous culture using the genetically modified microorganism Pseudomonas sp. B13 FR1 SN45P. The strain was able to mineralize the single compounds as well as the substrate mixture completely. Conversion of the three compounds in the substrate mixture proceeded simultaneously. Maximum specific substrate conversion rates were calculated to be 0.9 g g{sup {minus}1} h{sup {minus}1} for 3 CB and 4CB and 1.1 g g{sup {minus}1} h{sup {minus}1} for 4MB. Mass balances indicated the transient accumulation of pathway intermediates during batch cultivations. Hence, the rate limiting step in the degradative pathway is not the initial microbial attack of the original substrate or its transport through the cell membrane. Degradation rates on 3CB were comparable to those of the parent strain Pseudomonas sp. B13. The stability of the degradation pathways of strain Pseudomonas sp. B13 FR1 SN45P could be demonstrated in a continuous cultivation over 3.5 months (734 generation times) on 3CB, 4MB, and 4CB, which were used a single carbon sources one after the other.

Mueller, R.; Deckwer, W.D.; Hecht, V. [Gesellschaft fuer Biotechnologische Forschung mbH, Braunschweig (Germany)

1996-09-05

278

2-[(2-Acet-oxy-benzo-yl)-oxy]benzoic acid  

PubMed Central

The title compound, C16H12O6, is a common impurity of ortho-acetylsalicylic acid (aspirin). The benzene rings form a dihedral angle of 81.9?(1) while the acetyl and carboxyl groups form dihedral angles of 74.0?(1) and 26.4?(2), respectively, with the benzene rings to which they are bound. In the crystal, molecules are linked by pairs of OH?O hydrogen bonds between the carboxyl groups, forming inversion dimers.

Solanko, Katarzyna A.; Bond, Andrew D.

2012-01-01

279

In situ direct measurement of vapor pressures and thermodynamic parameters of volatile organic materials in the vapor phase: benzoic acid, ferrocene, and naphthalene.  

PubMed

We report the direct determination of vapor pressures and optical and thermodynamic parameters of powders of low-volatile materials in their vapor phase using a commercial UV/Vis spectrometer. This methodology is based on the linear proportionality between the density of the saturated gas of the material and the absorbance of the gas at different temperatures. The vapor pressure values determined for benzoic acid and ferrocene are in good agreement with those reported in the literature with ?2-7?% uncertainty. Thermodynamic parameters of benzoic acid, ferrocene, and naphthalene are determined in situ at temperatures below their melting points. The sublimation enthalpies of the investigated organic molecules are in excellent agreement with the ICTAC recommended values (less than 1?% difference). This method has been used to measure vapor pressures and thermodynamic parameters of organic volatile materials with vapor pressures of ?0.5-355 Pa in the 50-100?C temperature range. PMID:23606455

Hikal, Walid M; Weeks, Brandon L

2013-04-19

280

Adsorption of o-cresol and benzoic acid in an adsorber packed with an ion-exchange resin: A comparative study of diffusional models  

SciTech Connect

Both solid- and pore-diffusion models were employed to simulate the adsorption of o-cresol and benzoic acid in a fixed-bed adsorber packed with an anion-exchange resin. The equilibrium adsorption data were modeled by a Langmuir isotherm. When the shape of the adsorption isotherm was approximately linear (as in the case of o-cresol), both models agreed well with the experimental break-through data, and they could be effectively applied to predict the breakthrough curve of longer columns. For a favorable adsorption isotherm (say, benzoic acid), however, better results were obtained by using the solid-diffusion model. In addition to the shape of the adsorption isotherm, several factors, such as the type of adsorbent, modeling of equilibrium data, computation efficiency, and concentration dependence of the intraparticle diffusivity, should also be taken into account for selecting a suitable diffusion model.

Run-Tun Huang; Teh-Liang Chen; Hung-Shan Weng [National Cheng Kung Univ., Taiwan (China)

1994-10-01

281

Influence of metal salts of 4-(2, 4, 6-trinitroanilino) benzoic acid on the burnining rate of double base propellants  

Microsoft Academic Search

Cobalt, Nickel, Copper and Lead salts of 4-(2, 4, 6-trinitroanilino) benzoic acid have been evaluated as ballistic modifiers in double base propellant formulations. Measurements showed considerable increase in burning rate over the control propellant, in presence of salts at all pressures in the range 3.43 8.82 MPa. The effect of the lead salt, however, was more pronounced and showed

S. M. Pundlik; R. S. Palaiah; J. K. Nair; T. Mukundan; S. N. Singh; Haridwar Singh

2001-01-01

282

Effects of microwaves on selective oxidation of toluene to benzoic acid over a V 2O 5\\/TiO 2 system  

Microsoft Academic Search

Two series of catalysts, V2O5\\/TiO2 and modified V2O5\\/TiO2, were prepared with a conventional impregnation method. They were tested in the selective oxidation of toluene to benzoic acid under microwave irradiation. The reaction conditions were optimized over V2O5\\/TiO2. It was found that in the microwave catalytic process the optimum reactor bed temperature of the titled reaction decreases to 500K (600K in

Ye Liu; Yong Lu; Pu Liu; Runxiong Gao; Yuanqi Yin

1998-01-01

283

Proton tunnelling in the hydrogen bonds of halogen-substituted derivatives of benzoic acid studied by NMR relaxometry: the case of large energy asymmetry  

Microsoft Academic Search

The concerted two proton transfer in the hydrogen bonds of para-halogen substituted derivatives of benzoic acid has been investigated using conventional NMR relaxometry combined with field-cycling measurements of the magnetic field dependence of the proton spinlattice relaxation rate. Thus, the inverse correlation time describing the proton transfer process has been determined over a wide range of temperature. The energy difference

A. J. Horsewill; C. J. McGloin; H. P. Trommsdorff; M. R. Johnson

2003-01-01

284

Beneficial effects of Mn(III)tetrakis (4-benzoic acid) porphyrin (MnTBAP), a superoxide dismutase mimetic, in carrageenan-induced pleurisy  

Microsoft Academic Search

Peroxynitrite, a potent cytotoxic oxidant formed by the reaction of NO with superoxide anion, has been proposed to have major pathogenetic role in inflammatory process. Here we have investigated the therapeutic efficacy of Mn(III)tetrakis (4-benzoic acid) porphyrin (MnTBAP), a novel superoxide dismutase mimetic that possesses peroxynitrite scavenging effect, in rats subjected to carrageenan-induced pleurisy. In vivo treatment with MnTBAP (3

Salvatore Cuzzocrea; Basilia Zingarelli; Giuseppina Costantino; Achille P. Caputi

1999-01-01

285

Crystal structure of complexes of bivalent Co, Ni, and Cd with anions of benzoic and 2-(acetylamino)-5-nitrobenzoic acids  

SciTech Connect

The structure of three complexes of bivalent metals (cobalt, nickel, and cadmium) with anions of benzoic (HL{sup 1}) and 2-(acetylamino)-5-nitrobenzoic (HL{sup 2}) acids, namely, [Co{sub 2}{sup 1} (H{sub 2}O){sub 2}({mu}-C{sub 4}H{sub 4}N{sub 2})]{sub n} (I), [NiL{sup 2}(H{sub 2}O){sub 5}]L{sup 2} {center_dot} 2H{sub 2}O (II), and [Cd({mu}-L{sup 2}){sub 2}(H{sub 2}O){sub 2}]{sub n} {center_dot} 2nH{sub 2}O (III), is determined. In chainlike structure I, cobalt atoms are connected by bridging pyrazine molecules; structure II contains isolated complexes. In structure III, centrosymmetric (CdOCO){sub 2} cycles and polymeric ribbons are formed due to the coordination of the carboxylate group of the L{sup 2} ligand to two cadmium atoms.

Rzaeva, M. F. [Azerbaijan State Agricultural University (Azerbaijan); Askerov, R. K. [Baku State University (Azerbaijan); Movsumov, E. M. [Azerbaijan State Agricultural University (Azerbaijan); Sergienko, V. S.; Ilyukhin, A. B. [Russian Academy of Sciences, Kurnakov Institute of General and Inorganic Chemistry (Russian Federation)

2012-03-15

286

Temperature-induced dynamical conformational disorder in 4-vinyl benzoic acid molecular crystals: A molecular simulation study  

NASA Astrophysics Data System (ADS)

Extensive molecular simulations are carried out as a function of temperature to understand and quantify the conformational disorder in molecular crystals of 4-vinyl benzoic acid. The conformational disorder is found to be dynamic and associated with a flip-flop motion of vinyl groups. The population of minor conformer is less than 3% up to 300 K and is 13.2% at 350 K and these results are consistent with the experimental observations. At still higher temperatures, the population of minor conformer increases up to 25%. The evolution of structure at both molecular and unit-cell level of the molecular crystal as a function of temperature has been characterized by various quantities such as radial distribution functions, average cell parameters, volume, and interaction energies. The van't Hoff plot shows a nonlinear behavior at lower temperatures as it has been reported recently by Ogawa and co-workers in the case of stilbene, azobenzene [J. Am. Chem. Soc. 126, 3539 (2004)], and N-(4-methylbenzylidene)-4-methylaniline [Acta Crystallogr, Sect. B. Struct. Sci. B60, 589 (2004)] molecular crystals. A set of rigid body simulations were also carried out to quantify the effect of conformational disorder on structural quantities such as unit-cell volume and interaction energy. The anomalous shrinkage of vinyl C=C bond length as a function of temperature has been explained by combining the results of simulations and a set of constrained optimizations using ab initio electronic structure calculations for various molecular structures differing in torsional angle.

Murugan, N. Arul

2005-09-01

287

Effect of MN (III) tetrakis (4-benzoic acid) porphyrin by photodynamically generated free radicals on SODs keratinocytes.  

PubMed

Superoxide, a reactive form of oxygen, can be produced in vivo either in normal and under pathophysiologic conditions or by photosensitizing chemicals, as during photodynamic treatment. Photodynamic therapies (PDT), widely adopted in Dermatology and Oncology, are known to generate reactive oxygen species (ROS) and may contribute to structural alterations and oxidatively generated modifications of cellular antioxidants. We hypothesized that over-production of free radicals would decrease the enzymatic activities of endogenous cellular antioxidants. To test this hypothesis, keratinocytes were treated with the photosensitizer Photofrin plus visible light to produce free radicals and CuZnSOD and MnSOD activities were measured. Photodynamic treatment of keratinocytes increases malonylaldehyde production, nitrotyrosine staining and superoxide production. The enzymatic activities of CuZnSOD and MnSOD were significantly decreased after Photofrin plus visible light treatment. Our results suggest that the main cellular antioxidant system can be inactivated by photodynamically generated ROS. Pretreatment of keratinocytes with free radicals scavenger such as Mn (III) tetrakis (4-benzoic acid) porphyrin (MnTBAP) was able to restore the endogenous antioxidant system activities, inhibiting the MDA formation, nitrotyrosine staining and superoxide formation. Antioxidant therapy could therefore be a useful tool in protecting healthy epidermal cells against common side effects induced by antitumor targeted therapies. PMID:24152829

Nistico', S; Ventrice, D; Dagostino, C; Lauro, F; Ilari, S; Gliozzi, M; Colica, C; Musolino, V; Carresi, C; Strongoli, M C; Vecchio, I; Rizzo, M; Mollace, V; Muscoli, C

288

Viper venom-induced inflammation and inhibition of free radical formation by pure compound (2-hydroxy-4-methoxy benzoic acid) isolated and purified from anantamul ( Hemidesmus indicus R.Br) root extract  

Microsoft Academic Search

The present investigation explored the possible venom neutralizing effect of a pure compound (2-hydroxy-4-methoxy benzoic acid) isolated and purified from the methanolic root extract of Hemidesmus indicus R.Rr. 2-OH-4-MeO benzoic acid possessed potent anti-inflammatory, antipyretic and antioxidant properties. The compound effectively neutralized inflammation induced by Vipera russelli venom in male albino mice and reduced cotton pellet-induced granuloma in rats. The

M. I. Alam; A. Gomes

1998-01-01

289

4-Aza-1-azoniabicyclo-[2.2.2]octa-ne-2-amino-benzoate-2-amino-benzoic acid (1/1/1).  

PubMed

A 4-aza-1-azoniabicyclo-[2.2.2]octane cation, a 2-amino-benzoate anion and a neutral 2-amino-benzoic acid mol-ecule comprise the asymmetric unit of the title compound, C(6)H(13)N(2) (+)C(7)H(6)NO(2) (-)C(7)H(7)NO(2). An intra-molecular N-H?O hydrogen bond occurs in the anion and in the neutral 2-amino-benzoic acid mol-ecule. The cation provides a charge-assisted N-H?O hydrogen bond to the anion, and the 2-amino-benzoic acid mol-ecule forms an O-H?N hydrogen bond to the unprotonated amino N atom in the cation. In this way, a three-component aggregate is formed. These are connected into a three-dimensional network by amino-carboxyl-ate N-H?O hydrogen bonds. N-H?N hydrogen bonds are also observed. PMID:22219964

Arman, Hadi D; Kaulgud, Trupta; Tiekink, Edward R T

2011-10-12

290

XAS studies on Cu(II) complexes with derivatives of phenoxyacetic and benzoic acids  

NASA Astrophysics Data System (ADS)

The geometry of metal-ligand interaction of three Cu(II) complexes with carboxylic acids has been determined by X-ray absorption spectroscopy. Around Cu(II) cation in a complex with 4-methoxy-3-nitrobenzoate anion a square geometry is formed by the carboxylate groups from two monodentate ligands and two water molecules. The tetragonal pyramid around Cu(II) composed by two carboxylate groups from two monodentate ligands and three water molecules is observed for 2-methoxyphenoxyacetate complex. The 4-chlorophenoxyacetate complex with Cu(II) exhibits tetragonal-bipyramidal geometry, with two carboxylate and two ether oxygen atoms from bidentate ligands and two water molecules in the coordination sphere.

Klepka, Marcin T.; Drzewiecka, Aleksandra; Wolska, Anna; Ferenc, Wieslawa

2012-11-01

291

C 1s Near Edge X-ray Absorption Fine Structure (NEXAFS) of substituted benzoic acids: a theoretical and experimental study  

SciTech Connect

Ab initio calculations are performed to explain the discrete transitions in experimental C 1s-NEXAFS (near edge X-ray absorption fine structure) spectra of various benzoic acid derivates. Transition energies and oscillator strengths of the contributing C 1s-{pi}* excitations are computed using the ADC(2) (second-order algebraic-diagrammatic construction) method. This method is demonstrated to be well suited for the finite electronic systems represented by these simple organic acids. There is good agreement between experiment and theory reproducing all the relevant spectral features. Some transitions can only be assigned based on a theoretical foundation. Remaining discrepancies between experimental and computed spectra are discussed.

Baldea,I.; Schimmelpfennig, B.; Plaschke, M.; Rothe, J.; Schirmer, J.; Trofimov, A.; Fanghaenel, T.

2007-01-01

292

Preparation and spectral characterization of fluorescence probes based on 4-N,N-dimethylamino benzoic acid and sterically hindered amines.  

PubMed

The adducts of simple chromophore 4-N,N-dimethylamino benzoic acid with 2,2,6,6-tetrametyl-4-hydroxy- or 4-amino-piperidine were examined as fluorescence probes (spin double sensors) to monitor radical processes. The links in the adducts were either an ester or amide group, and the sterically hindered amines were in the form of -NH, -NO and -NOR. The spectral properties of the three related derivatives (esters or amides) were quite similar. The maxima of the absorption spectra were in the range of 295-315 nm, and the maximum of fluorescence was located in the range of 330-360 nm, depending on the polarity of the solvent. In polar solvents, a red-shifted fluorescence band at 460-475 nm was observed. The fluorescence of these derivatives was rather weak as compared to anthracene under the same conditions. The Stokes shift was large, as high as 6,000 cm(-1), indicating the formation of a twisted intra-molecular charge transfer (TICT) state. No large differences in Stokes shifts were observed in polymer matrices of poly(methyl methacrylate), polystyrene and poly(vinyl chloride). The extent of intramolecular quenching was expressed as ?(NX)/?(NO) (X = H, NOR) and was in the range of 1-3 in solution and as high as 8 in polymer matrices. The low efficiency of intramolecular quenching limits the application of these new adducts as fluorescence probes for the monitoring of radical processes in solution but favors their application in polymer matrices. PMID:22730137

Ksa, Csaba; Danko, Martin; Hrdlovi?, Pavol

2012-06-24

293

Two tobacco genes induced by infection, elicitor and salicylic acid encode glucosyltransferases acting on phenylpropanoids and benzoic acid derivatives, including salicylic acid  

Microsoft Academic Search

Two tobacco genes (TOGT) with homology to glucosyltransferase genes known to be induced by salicylic acid (SA) also responded rapidly to a fungal elicitor or to an avirulent pathogen. SA, although an efficient inducer, was shown not to be essential in the signal transduction pathway regulating TOGT gene expression during the resistance response. Recombinant TOGT proteins produced in Escherichia coli

Laurence Fraissinet-Tachet; Rachel Baltz; Julie Chong; Serge Kauffmann; Bernard Fritig; Patrick Saindrenan

1998-01-01

294

Synthesis and Protective Effect of New Ligustrazine-Benzoic Acid Derivatives against CoCl2-Induced Neurotoxicity in Differentiated PC12 Cells.  

PubMed

A series of novel ligustrazine-benzoic acid derivatives were synthesized and evaluated for their protective effect against cobalt chloride-induced neurotoxicity in differentiated PC12 cells. Combining hematoxylin and eosin staining, we found compound that (3,5,6-trimethylpyrazin-2-yl)methyl 3-methoxy-4-[(3,5,6-trimethylpyrazin-2-yl)methoxy]benzoate (4a) displayed promising protective effect on the proliferation of the injured PC12 cells (EC50 = 4.249 M). Structure-activity relationships are brie?y discussed. PMID:24145795

Wang, Penglong; Zhang, Honggui; Chu, Fuhao; Xu, Xin; Lin, Jinxuan; Chen, Chunxiao; Li, Guoliang; Cheng, Yatao; Wang, Lin; Li, Qiang; Zhang, Yuzhong; Lei, Haimin

2013-10-18

295

Comparison of the antitumor activity of DTIC and 1- p -(3,3-dimethyl-1-triazeno) benzoic acid potassium salt on murine transplantable tumors and their hematological toxicity  

Microsoft Academic Search

This study describes a comparison of 1-p-(3,3-dimethyl-1-triazeno)benzoic acid potassium salt (DM-COOK) and imidazole-4-carboxamide,5-(3,3-dimethyl-1-triazeno) (DTIC) with reference to antitumor activity on different murine tumors and hematological toxicity. DM-COOK appeared comparably or slightly more effective in L1210, P388, and M5 tumors in the mouse. However, when the treatment of mice bearing M5 with DM-COOK was combined with surgical removal of the primary

Tina Colombo; Maurizio D'Incalci

1984-01-01

296

catena-Poly[[aqua-(benzoato-?2 O,O?)(benzoic acid-?O)calcium]-?3-benzoato-?4 O:O,O?:O?  

PubMed Central

In title compound, [Ca(C7H5O2)2(C7H6O2)(H2O)]n, the eightfold-coordinated CaII ion is bonded to four carboxylate O atoms from two benzoate ions, an O atom from benzoic acid and a water O atom. One of the carboxylate groups bridges adjacent Ca2+ ions, forming a polymeric ribbon structure parallel to [010]. In the crystal, the benzoate anions and water molecule interact by way of inter- and intramolecular OH?O hydrogen bonds.

Azizov, Olimjon; Kadirova, Zukhra; Azizov, Tohir; Tolipov, Samat; Ibragimov, Bakhtiyar

2011-01-01

297

Vapor phase oxidation of benzoic acid to phenol over a novel catalyst system consisting of NiO and NiFe{sub 2}O{sub 4}  

SciTech Connect

NiO and Fe{sub 2}O{sub 3} were found to show the catalytic activities for the vapor phase oxidation of benzoic acid to form phenol. Furthermore, the enhancement of the activity and phenol selectivity were achieved by combined Ni and Fe components prepared by precipitation. The calcination temperature and the atomic ratio of Ni to Fe were found to be important for the enhancement of activity. The homogeneous distribution profile of NiO and NiFe{sub 2}O{sub 4} on the surface and in the bulk of the catalyst is essential for the optimization of phenol formation. 32 refs., 7 figs., 4 tabs.

Miki, Jun; Asanuma, Minoru; Tachibana, Yakudo [NKK Corporation, Kawasaki (Japan)] [and others

1995-02-01

298

Crystal structure of a new benzoic acid inhibitor of influenza neuraminidase bound with a new tilt induced by overpacking subsite C6  

PubMed Central

Background Influenza neuraminidase (NA) is an important target for antiviral inhibitors since its active site is highly conserved such that inhibitors can be cross-reactive against multiple types and subtypes of influenza. Here, we discuss the crystal structure of neuraminidase subtype N9 complexed with a new benzoic acid based inhibitor (2) that was designed to add contacts by overpacking one side of the active site pocket. Inhibitor 2 uses benzoic acid to mimic the pyranose ring, a bis-(hydroxymethyl)-substituted 2-pyrrolidinone ring in place of the N-acetyl group of the sialic acid, and a branched aliphatic structure to fill the sialic acid C6 subsite. Results Inhibitor 2 {4-[2,2-bis(hydroxymethyl)-5-oxo-pyrrolidin-1-yl]-3-[(dipropylamino)methyl)]benzoic acid} was soaked into crystals of neuraminidase of A/tern/Australia/G70c/75 (N9), and the structure refined with 1.55? X-ray data. The benzene ring of the inhibitor tilted 8.9 compared to the previous compound (1), and the number of contacts, including hydrogen bonds, increased. However, the IC50 for compound 2 remained in the low micromolar range, likely because one propyl group was disordered. In this high-resolution structure of NA isolated from virus grown in chicken eggs, we found electron density for additional sugar units on the N-linked glycans compared to previous neuraminidase structures. In particular, seven mannoses and two N-acetylglucosamines are visible in the glycan attached to Asn200. This long, branched high-mannose glycan makes significant contacts with the neighboring subunit. Conclusions We designed inhibitor 2 with an extended substituent at C4-corresponding to C6 of sialic acid-to increase the contact surface in the C6-subsite and to force the benzene ring to tilt to maximize these interactions while retaining the interactions of the carboxylate and the pyrolidinone substituents. The crystal structure at 1.55? showed that we partially succeeded in that the ring in 2 is tilted relative to 1 and the number of contacts increased, but one hydrophobic branch makes no contacts, perhaps explaining why the IC50 did not decrease. Future design efforts will include branches of unequal length so that both branches may be accommodated in the C6-subsite without conformational disorder. The high-mannose glycan attached to Asn200 makes several inter-subunit contacts and appears to stabilize the tetramer.

2012-01-01

299

D77, one benzoic acid derivative, functions as a novel anti-HIV-1 inhibitor targeting the interaction between integrase and cellular LEDGF/p75  

SciTech Connect

Integration of viral-DNA into host chromosome mediated by the viral protein HIV-1 integrase (IN) is an essential step in the HIV-1 life cycle. In this process, Lens epithelium-derived growth factor (LEDGF/p75) is discovered to function as a cellular co-factor for integration. Since LEDGF/p75 plays an important role in HIV integration, disruption of the LEDGF/p75 interaction with IN has provided a special interest for anti-HIV agent discovery. In this work, we reported that a benzoic acid derivative, 4-[(5-bromo-4-{l_brace}[2,4-dioxo-3-(2-oxo-2-phenylethyl) -1,3-thiazolidin-5-ylidene]methyl{r_brace}-2-ethoxyphenoxy)methyl]benzoic acid (D77) could potently inhibit the IN-LEDGF/p75 interaction and affect the HIV-1 IN nuclear distribution thus exhibiting antiretroviral activity. Molecular docking with site-directed mutagenesis analysis and surface plasmon resonance (SPR) binding assays has clarified possible binding mode of D77 against HIV-1 integrase. As the firstly discovered small molecular compound targeting HIV-1 integrase interaction with LEDGF/p75, D77 might supply useful structural information for further anti-HIV agent discovery.

Du Li [Drug Discovery and Design Center, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai 201203 (China); Zhao Yaxue [School of Pharmacy, East China University of Science and Technology, Shanghai 200237 (China); Chen, Jing [Drug Discovery and Design Center, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai 201203 (China); Yang Liumeng; Zheng Yongtang [Laboratory of Molecular Immunopharmacology, Key Laboratory of Animal Models and Human Disease Mechanisms, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650223 (China); Tang Yun [School of Pharmacy, East China University of Science and Technology, Shanghai 200237 (China)], E-mail: ytang234@ecust.edu.cn; Shen Xu [Drug Discovery and Design Center, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai 201203 (China); School of Pharmacy, East China University of Science and Technology, Shanghai 200237 (China)], E-mail: xshen@mail.shcnc.ac.cn; Jiang Hualiang [Drug Discovery and Design Center, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai 201203 (China); School of Pharmacy, East China University of Science and Technology, Shanghai 200237 (China)

2008-10-10

300

Cellular and Subcellular Localization of S-Adenosyl-l-Methionine:Benzoic Acid Carboxyl Methyltransferase, the Enzyme Responsible for Biosynthesis of the Volatile Ester Methylbenzoate in Snapdragon Flowers1  

PubMed Central

The benzenoid ester, methylbenzoate is one of the most abundant scent compounds detected in the majority of snapdragon (Antirrhinum majus) varieties. It is produced in upper and lower lobes of petals by enzymatic methylation of benzoic acid in the reaction catalyzed by S-adenosyl-l-methionine:benzoic acid carboxyl methyltransferase (BAMT). To identify the location of methylbenzoate biosynthesis, we conducted an extensive immunolocalization study by light and electron microscopy at cellular and subcellular levels using antibodies against BAMT protein. BAMT was immunolocalized predominantly in the conical cells of the inner epidermal layer and, to a much lesser extent, in the cells of the outer epidermis of snapdragon flower petal lobes. It was also located in the inner epidermis of the corolla tube with little BAMT protein detected in the outer epidermis and in the yellow hairs within the tube on the bee's way to the nectar. These results strongly suggest that scent biosynthetic genes are expressed almost exclusively in the epidermal cells of floral organs. Immunogold labeling studies reveal that BAMT is a cytosolic enzyme, suggesting cytosolic location of methylbenzoate biosynthesis. The concentration of scent production on flower surfaces that face the pollinators during landing may increase pollination efficiency and also help to minimize the biosynthetic cost of advertising for pollinators.

Kolosova, Natalia; Sherman, Debra; Karlson, Dale; Dudareva, Natalia

2001-01-01

301

2-[(1H-Benzimidazol-2-ylmethyl)-amino]-benzoic acid methyl ester: Crystal structure, DFT calculations and biological activity evaluation  

NASA Astrophysics Data System (ADS)

In the present study, structural properties of 2-[(1H-benzimidazol-2-ylmethyl)-amino]-benzoic acid methyl ester have been studied extensively by spectral methods and X-ray crystallography. Quantum mechanical calculations of energies, geometries, vibrational wavenumbers, NMR and electronic transitions were carried out by DFT using B3LYP functional combined with 6-31G(d) basis set. Natural bond orbitals (NBO) analysis and frontier molecular orbitals were performed at the same level of theory. DFT calculations showed good agreement between the theoretical and experimental values of optimized and X-ray structure as well as between the vibrational and NMR spectroscopy. The title compound was screened for its antibacterial activity referring to Tetracycline as standard antibacterial agent.

Ghani, Nour T. Abdel; Mansour, Ahmed M.

2011-10-01

302

Synthesis, crystal structures and optical properties of two coordination polymers from 4-(1H-tetrazol-5-yl) benzoic acid  

Microsoft Academic Search

The coordination polymers [Mn(4-TZBA2?)(H2O)2] (1) and [Mn4(4-TZBA2?)4(?2-H2O)2(H2O)(py)] (2) (py=pyridine) were prepared by the treatment of Mn(ClO4)26H2O with 4-(1H-tetrazol-5-yl) benzoic acid (H2(4-TZBA)) under hydrothermal conditions. Compound 2 has nanosize triangular channels with a dimension of 11.92411.68614.835, in which guest water molecules are encapsulated. Compound 1 and 2 show strong fluorescence at room temperature in the solid state and compound 2 exhibits

Zhaopeng Yu; Yu Xie; Sujing Wang; Guoping Yong; Zhiyong Wang

2008-01-01

303

Crystal and Molecular Structure of the 1:2 Salt Formed Between 1,2-(4-Pyridyl)Ethane and 2-(4-Hydroxyphenylazo)Benzoic Acid  

Microsoft Academic Search

\\u000a AbstractProton transfer occurred during co-crystallization of 1,2-(4-pyridyl)ethane with 2-(4-hydroxyphenylazo)benzoic acid to yield\\u000a a salt comprising a 1:2 ratio of 1,2-bis(4-pyridinium)ethane dications and 2-(4-hydroxyphenylazo)benzoate anions. Centrosymmetrically\\u000a related anions associate by charge-assisted OHO hydrogen bonds to form 24-membered {OC3N2C4OH}2 synthons. These are connected into a supramolecular polymer via charge-assisted NHO hydrogen bonds involving the 1,2-bis(4-pyridinium)ethane\\u000a dications. The compound crystallizes in the triclinic

Ellen M. Corlette; Edward R. T. Tiekink

2009-01-01

304

4-Amino-N-(4,6-dimethyl-pyrimidin-2-yl)-benzene-sulfonamide-4-nitro-benzoic acid (1/1)  

PubMed Central

In the asymmetric unit of the title co-crystal, C7H5NO4C12H14N4O2S, there are two independent but conformationally similar heterodimers, which are formed through intermolecular NH?Ocarboxy and carboxylpyrimidine OH?N hydrogen-bond pairs, giving a cyclic motif [graph set R 2 2(8)]. The dihedral angles between the rings in the sulfonamide molecules are 78.77?(8) and 82.33?(9) while the dihedral angles between the ring and the CO2H group in the acids are 2.19?(9) and 7.02?(10). A two-dimensional structure parallel to the ab plane is generated from the heterodimer units through hydrogen-bonding associations between NH2 and sulfone groups. Between neighbouring two-dimensional arrays there are two types of aromatic ?? stacking interactions involving either one of the pyrimidine rings and a 4-nitrobenzoic acid molecule [minimum ring centroid separation = 3.5886?(9)?] or two acid molecules [minimum ring centroid separation = 3.7236?(10)?].

Smith, Graham; Wermuth, Urs D.

2012-01-01

305

Suitable combination of promoter and micellar catalyst for kilo fold rate acceleration on benzaldehyde to benzoic acid conversion in aqueous media at room temperature: A kinetic approach  

NASA Astrophysics Data System (ADS)

The kinetics of oxidation of benzaldehyde by chromic acid in aqueous and aqueous surfactant (sodium dodecyl sulfate, SDS, alkyl phenyl polyethylene glycol, Triton X-100 and N-cetylpyridinium chloride, CPC) media have been investigated in the presence of promoter at 303 K. The pseudo-first-order rate constants (kobs) were determined from a logarithmic plot of absorbance as a function time. The rate constants were found to increase with introduction of heteroaromatic nitrogen base promoters such as Picolinic acid (PA), 2,2'-bipyridine (bipy) and 1,10-phenanthroline (phen). The product benzoic acid has been characterized by conventional melting point experiment, NMR, HRMS and FTIR spectral analysis. The mechanism of both unpromoted and promoted reaction path has been proposed for the reaction. In presence of the anionic surfactant SDS, cationic surfactant CPC and neutral surfactant TX-100 the reaction can undergo simultaneously in both aqueous and micellar phase with an enhanced rate of oxidation in the micellar phase. Both SDS and TX-100 produce normal micellar effect whereas CPC produce reverse micellar effect in the presence of benzaldehyde. The observed net enhancement of rate effects has been explained by considering the hydrophobic and electrostatic interaction between the surfactants and reactants. SDS and bipy combination is the suitable one for benzaldehyde oxidation.

Ghosh, Aniruddha; Saha, Rumpa; Ghosh, Sumanta K.; Mukherjee, Kakali; Saha, Bidyut

2013-05-01

306

Biodegradation of aromatic compounds by white rot and ectomycorrhizal fungal species and the accumulation of chlorinated benzoic acid in ectomycorrhizal pine seedlings.  

PubMed

The capability of different white rot (WR, Heterobasidion annosum, Phanerochaete chrysosporium, Trametes versicolor) and ectomycorrhizal (ECM, Paxillus involutus, Suillus bovinus) fungal species to degrade different aromatic compounds and the absorption of 3-chlorobenzoic acid (3-CBA) by ECM pine seedlings was examined. The effect of aromatic compounds on the fungal biomass development varied considerably and depended on (a) the compound, (b) the external concentration, and (c) the fungal species. The highest effect on the fungal biomass development was observed for 3-CBA. Generally the tolerance of WR fungi against aromatic compounds was higher than that of the biotrophic fungal species. The capability of different fungi to degrade aromatic substances varied between the species but not generally between biotrophic and saprotrophic fungi. The highest degradation capability for aromatic compounds was detected for T. versicolor and H. annosum, whereas for Phanerochaete chrysosporium and the ECM fungi lower degradation rates were found. However, Paxillus involutus and S. bovinus showed comparable degradation rates at low concentrations of benzoic acid and 4-hydroxybenzoic acid. In contrast to liquid cultures, where no biodegradation of 3-CBA by S. bovinus was observed, mycorrhizal pines inoculated with S. bovinus showed a low capability to remove 3-CBA from soil substrates. Additional X-ray microanalytical investigations showed, that 3-CBA supplied to mycorrhizal plants was accumulated in the root cell cytoplasm and is translocated across the endodermis to the shoot of mycorrhizal pine seedlings. PMID:12363308

Dittmann, Jens; Heyser, Wolfgang; Bcking, Heike

2002-10-01

307

Blockade of human neutrophil activation by 2-[2-propyl-3-[3-[2-ethyl-4-(4-fluorophenyl)-5-hydroxyphenoxy]propoxy]phenoxy]benzoic acid (LY293111), a novel leukotriene B 4 receptor antagonist  

Microsoft Academic Search

Leukotriene B4 (LTB4), a naturally occurring pro-inflammatory product of arachidonic acid metabolism, has been associated with human inflammatory disease. This study compares the abilities of two LTB4 receptor antagonists, 2-[2-propyl-3-[3-[2-ethyl-4-(4-fluorophenyl)-5-hydroxyphenoxy]-propoxy]phenoxy]benzoic acid (LY293111) and 7-[3-(4-acetyl-3-methoxy-2-propylphenoxy)-propoxy]-3, 4-dihydro-8-propyl-2H-1-benzopyran-2-carboxylic acid (SC-41930), to displace LTB4 binding and their functional blockade of human neutrophil activation. LY293111 inhibited the binding of [3H]LTB4 with a Ki, of 25

Philip Marder; J. Scott Sawyer; Larry L. Froelich; Larry L. Mann; Stephen M. Spaethe

1995-01-01

308

New bitter-masking compounds: hydroxylated benzoic acid amides of aromatic amines as structural analogues of homoeriodictyol.  

PubMed

Starting from the known bitter-masking flavanones eriodictyol and homoeriodictyol from herba santa some structurally related hydroxybenzoic acid amides of benzylamines were synthesized and evaluated as masking agents toward bitterness of caffeine by sensory methods. The closest structural relatives of homoeriodictyol, the hydroxybenzoic acid vanillylamides 5-9, were the most active and were able to reduce the bitterness of a 500 mg L(-1) caffeine solution by about 30% at a concentration of 100 mg L(-1). 2,4-Dihydroxybenzoic acid vanillylamide 7 showed a clear dose-dependent activity as inhibitor of the bitter taste of caffein between 5 and 500 mg L(-1). Additionally, it was possible to reduce the bitterness of quinine and salicine but not of the bitter peptide N-l-leucyl-l-tryptophan. Combinations of homoeriodictyol and amide 7 showed no synergistic or antagonistic changes in activity. The results for model compound 7 suggested that the hitherto unknown masking mechanism is probably the same for flavanones and the new amides. In the future, the new amides may be alternatives for the expensive flavanones to create flavor solutions to mask bitterness of pharmaceuticals or foodstuffs. PMID:17061836

Ley, Jakob P; Blings, Maria; Paetz, Susanne; Krammer, Gerhard E; Bertram, Heinz-Jrgen

2006-11-01

309

The differential influence of non-iodinated and mono- or diiodinated benzoic acids on cellular and nuclear uptake of the nuclear localization sequence of the SV 40 T antigen.  

PubMed

We synthesized several novel compounds to evaluate the different effects of non-iodinated and mono- or diiodinated benzoic acid on the cellular and nuclear uptake of the SV 40 T antigen nuclear localization sequence (NLS) in human LN18 and U373 glioma cells. The skeletal structure of all the conjugates contained the fluorescein isothiocyanate (FITC)-labeled NLS of the SV 40T antigen, to which either benzoic acid, mono- or diiodobenzoic acid was coupled. As shown by confocal laser scanning microscopy (CLSM) and fluorescence-activated cell sorting (FACS), the basic FITC-labeled NLS alone was taken up by the nuclei of only a few glioma cells which remained intact. The coupling of non-iodinated benzoic acid (BA) did not result in a markedly larger number of nuclearly stained cells. A very marked increase in cells with nuclear staining was found with the conjugate containing monoiodobenzoic acid (MIBA). This was also associated with a high cell death rate. Similar results were obtained with the conjugate containing diiodobenzoic acid (DIBA). However, coincubation with free mono- or diiodobenzoic acid and the basic FITC-labeled NLS did not result in a marked change in the number of strongly stained cells or cell viability compared to the results of incubation with the FITC-labeled NLS alone. Surprisingly, FITC-labeled MIBA- and DIBA-conjugates containing a scrambled SV 40 T antigen NLS were also taken up by the cell nuclei of LN18 and U373 glioma cells and led to cell death. Such mono- or diiodobenzoic acid conjugates may therefore have potential in the development of new non-radioactive drugs against malignant glioma cells. PMID:18249512

Heckl, Stefan; Sturzu, Alexander; Regenbogen, Marc; Beck, Alexander; Gharabaghi, Alireza; Echner, Hartmut

2007-12-23

310

Application of ChemDraw NMR Tool: Correlation of Program-Generated (Super 13)C Chemical Shifts and pK[subscript a] Values of Para-Substituted Benzoic Acids  

ERIC Educational Resources Information Center

|A study uses the ChemDraw nuclear magnetic resonance spectroscopy (NMR) tool to process 15 para-substituted benzoic acids and generate (super 13)C NMR chemical shifts of C1 through C5. The data were plotted against their pK[subscript a] value and a fairly good linear fit was found for pK[subscript a] versus delta[subscript c1].|

Hongyi Wang

2005-01-01

311

Inclusion complex of charge transfer probe 4-amino-3-methyl benzoic acid methyl ester (AMBME) with ?-CD in aqueous and non-aqueous medium: medium dependent stoichiometry of the complex and orientation of probe molecule inside ?-CD nanocavity  

Microsoft Academic Search

The absorption and emission characteristics of donor?acceptor charge transfer system 4-amino-3-methyl benzoic acid methyl\\u000a ester (AMBME), capable of dual emission, i.e., local emission (LE) and charge transfer (CT) emission, have been investigated\\u000a inside the ?-cyclodextrin (?-CD) nanocavity in the aqueous and non-aqueous dimethylsulphoxide (DMSO) medium. Large enhancement\\u000a of both LE and CT band in aqueous ?-CD medium is due to

Amrita Chakraborty; Nikhil Guchhait

2008-01-01

312

Inclusion as a driving force for the intramolecular charge transfer (ICT) fluorescence of p -( N,N -diphenylamino)benzoic acid methyl ester (DPABME) in ?-cyclodextrin (?-CD) aqueous solution  

Microsoft Academic Search

A 1:1 inclusion complex between p-(N,N-diphenylamino)benzoic acid methyl ester (DPABME) molecule and ?-cyclodextrin (?-CD) in aqueous solution is formed with a\\u000a stabilization constant of ca. 45.653.59 M?1 at 25C. The formation of the complex is accompanied by enhancement of the long wavelength fluorescence at 510nm (attributed\\u000a to intramolecular charge transfer (ICT) due to twisting) relative to the normal fluorescence at

Khader A. Al-Hassan; Nail Saleh; Ideisan I. Abu-Abdoun; Yaser A. Yousef

2008-01-01

313

Determination of structural, spectrometric and nonlinear optical features of 2-(4-hydroxyphenylazo)benzoic acid by experimental techniques and quantum chemical calculations.  

PubMed

The optimized geometrical structure, vibrational and electronic transitions, chemical shifts and nonlinear optical properties of 2-(4-hydroxyphenylazo)benzoic acid (HABA) compound were presented in this study. The ground state geometrical structure and vibrational wavenumbers were carried out by using density functional (DFT/B3LYP) method with 6-311++G(d,p) basis set. The vibrational spectra of title compound were recorded in solid state with FT-IR and FT-Raman spectrometry in the range of 4000-400 cm(-1) and 4000-10 cm(-1); respectively. The fundamental assignments were done on the basis of the recorded spectra and total energy distribution (TED) of the vibrational modes. The (1)H and (13)C NMR spectra were recorded in deuterated DMSO solution, and gauge-invariant atomic orbitals (GIAOs) method was used to predict the isotropic chemical shifts. The UV-Vis absorption spectra of the compound were observed in the range of 200-800 nm in ethanol, methanol and water solvents. To investigate the nonlinear optical properties, the polarizability, anisotropy of polarizability and molecular first hyperpolarizability were computed. A detailed description of spectroscopic behaviors of compound was given based on the comparison of experimental measurements and theoretical computations. PMID:23295214

Cinar, Mehmet; Yildiz, Nihat; Karabacak, Mehmet; Kurt, Mustafa

2012-12-27

314

Linear free energy relationships applied to the reactivity and the 13C NMR chemical shifts in 4-[[(substituted phenyl)imino]methyl]benzoic acids  

NASA Astrophysics Data System (ADS)

Linear free energy relationships (LFER) were applied to the kinetic data and 13C NMR chemical shifts in 4-[[(substituted phenyl)imino]methyl]benzoic acids. The correlation analysis for the kinetic data and substituent-induced chemical shifts (SCS) with ? using single substituent parameter (SSP), as well as inductive (?I) and various resonance (?R) parameters using dual-substituent parameter (DSP), were carried out. The presented calculations account satisfactorily for the polar and resonance substituent effects having similar contributions at all carbons studied. Negative ? values were found for several correlations (reverse substituent effect). Exceptionally good Hammett correlation of 13C NMR chemical shifts of azomethine carbon with electrophilic substituent constants ?+ indicates a significant resonance interaction in the aniline part of molecules. The conformations of investigated compounds have been studied by the use of DFT method, and together with 13C NMR chemical shifts and kinetic data, give a better insight into the influence of such a structure on the transmission of electronic substituent effects. New ? constants for substituted phenyliminomethyl group have been calculated.

Marinkovi?, Aleksandar D.; Jovanovi?, Bratislav .; Assaleh, Fathi H.; Vajs, Vlatka V.; Jurani?, Milan I.

2012-03-01

315

FT-IR, FT-Raman, NMR and UV-vis spectra, vibrational assignments and DFT calculations of 4-butyl benzoic acid  

NASA Astrophysics Data System (ADS)

The solid phase FTIR and FT-Raman spectra of 4-butyl benzoic acid (4-BBA) have been recorded in the regions 400-4000 and 50-4000 cm -1, respectively. The spectra were interpreted in terms of fundamentals modes, combination and overtone bands. The structure of the molecule was optimized and the structural characteristics were determined by density functional theory (DFT) using B3LYP method with 6-311++G(d,p) as basis set. The vibrational frequencies were calculated for monomer and dimer by DFT method and were compared with the experimental frequencies, which yield good agreement between observed and calculated frequencies. The infrared and Raman spectra were also predicted from the calculated intensities. 13C and 1H NMR spectra were recorded and 13C and 1H nuclear magnetic resonance chemical shifts of the molecule were calculated using the gauge independent atomic orbital (GIAO) method. UV-visible spectrum of the compound was recorded in the region 200-400 nm and the electronic properties HOMO and LUMO energies were measured by time-dependent TD-DFT approach. The geometric parameters, energies, harmonic vibrational frequencies, IR intensities, Raman intensities, chemical shifts and absorption wavelengths were compared with the available experimental data of the molecule.

Karabacak, M.; Cinar, Z.; Kurt, M.; Sudha, S.; Sundaraganesan, N.

2012-01-01

316

Determination of structural, spectrometric and nonlinear optical features of 2-(4-hydroxyphenylazo)benzoic acid by experimental techniques and quantum chemical calculations  

NASA Astrophysics Data System (ADS)

The optimized geometrical structure, vibrational and electronic transitions, chemical shifts and nonlinear optical properties of 2-(4-hydroxyphenylazo)benzoic acid (HABA) compound were presented in this study. The ground state geometrical structure and vibrational wavenumbers were carried out by using density functional (DFT/B3LYP) method with 6-311++G(d,p) basis set. The vibrational spectra of title compound were recorded in solid state with FT-IR and FT-Raman spectrometry in the range of 4000-400 cm-1 and 4000-10 cm-1; respectively. The fundamental assignments were done on the basis of the recorded spectra and total energy distribution (TED) of the vibrational modes. The 1H and 13C NMR spectra were recorded in deuterated DMSO solution, and gauge-invariant atomic orbitals (GIAOs) method was used to predict the isotropic chemical shifts. The UV-Vis absorption spectra of the compound were observed in the range of 200-800 nm in ethanol, methanol and water solvents. To investigate the nonlinear optical properties, the polarizability, anisotropy of polarizability and molecular first hyperpolarizability were computed. A detailed description of spectroscopic behaviors of compound was given based on the comparison of experimental measurements and theoretical computations.

Cinar, Mehmet; Yildiz, Nihat; Karabacak, Mehmet; Kurt, Mustafa

2013-03-01

317

Internalisation of hybrid titanium dioxide/para-amino benzoic acid nanoparticles in human dendritic cells did not induce toxicity and changes in their functions.  

PubMed

Nanoparticles (NPs) have been reported to penetrate into human skin through lesional skin or follicular structures. Therefore, their ability to interact with dendritic cell (DC) was investigated using DCs generated from monocytes (mono-DCs). Hybrid titanium dioxide/para-amino benzoic acid (TiO(2)/PABA) NPs did not induce any cell toxicity. NPs were internalised into DCs through macropinocytosis and not by a receptor-mediated mechanism. Confocal microscopy showed that NPs were not detected in the nucleus. These data are confirmed by electronic microscopy which demonstrated that hybrid NPs were rapidly in contact with cellular membrane and localised into cytoplasmic vesicles without colocalisation with clathrin-coated vesicles. Hybrid NPs did not induce CD86 or HLA-DR overexpression or cytokine secretion (IL-8 and TNF-?) indicating no DC activation. Internalisation of hybrid NPs did not modify DC response towards sensitisers such as nickel and thimerosal or LPS used as positive controls. Moreover, hybrid NPs did not induce any oxidative stress implicated in DC activation process. After mono-DC irradiation by ultraviolet A (UVA), hybrid NP-treated cells did not produce UVA-induced reactive oxygen species (ROS) and exhibited a better cell viability compared with UVA-irradiated control cells, suggesting a protecting effect of hybrid TiO(2)/PABA NPs against UVA-induced ROS. PMID:20699112

Migdal, Camille; Rahal, Raed; Rubod, Alain; Callejon, Sylvie; Colomb, Evelyne; Atrux-Tallau, Nicolas; Haftek, Marek; Vincent, Claude; Serres, Mireille; Daniele, Stphane

2010-08-10

318

UV-Induced Order-to-Order Transition (OOT) in Thin Films of Supramolecular Diblock Copolymer Assemblies Containing 2-(4'-Hydroxyphenylazo)benzoic Acid  

NASA Astrophysics Data System (ADS)

Long-range lateral ordering and orientation in block copolymer thin films, which are highly desired for the applications requiring addressability, as in magnetic storage, may be obtained in a controlled way via an order-to-order transition (OOT), i.e. a morphological transition in a microphase-separated system. The photoisomerization of azobenzene results in volume changes that, when integrated into copolymers, can bring about phase transitions that, in turn, by sweeping the light across a surface, will promote long-range lateral ordering, similar to zone-refinement process used to produce large single crystals. We investigated UV-induced OOT in the supramolecule-assembled thin films of 2-(4-hydroxyphenylazo)benzoic acid and polystyrene-block-poly(2-vinylpyridine) diblock copolymer. Grazing incidence small angle X-ray scattering demonstrated that phase transition from lamellae to hexagonally packed cylinders occurred at 150 ^oC after UV radiation for 1 hour due to a significantly enhanced interfacial fluctuations induced by photoisomerization as evidenced by X-ray Reflectivity. This suggested that UV light can be utilized to control OOT in the supramolecule-assembled thin films and, hence, to fabricate long-range ordered nanostructures, and even smart responsive surfaces.

Chen, Wei; Wang, Jia-Yu; Wei, Xinyu; Balazs, Anna; Russell, Thomas

2009-03-01

319

Biosynthesis of biphenyls and benzophenones--evolution of benzoic acid-specific type III polyketide synthases in plants.  

PubMed

Type III polyketide synthases (PKSs) generate a diverse array of secondary metabolites by varying the starter substrate, the number of condensation reactions, and the mechanism of ring closure. Among the starter substrates used, benzoyl-CoA is a rare starter molecule. Biphenyl synthase (BIS) and benzophenone synthase (BPS) catalyze the formation of identical linear tetraketide intermediates from benzoyl-CoA and three molecules of malonyl-CoA but use alternative intramolecular cyclization reactions to form 3,5-dihydroxybiphenyl and 2,4,6-trihydroxybenzophenone, respectively. In a phylogenetic tree, BIS and BPS group together closely, indicating that they arise from a relatively recent functional diversification of a common ancestral gene. The functionally diverse PKSs, which include BIS and BPS, and the ubiquitously distributed chalcone synthases (CHSs) form separate clusters, which originate from a gene duplication event prior to the speciation of the angiosperms. BIS is the key enzyme of biphenyl metabolism. Biphenyls and the related dibenzofurans are the phytoalexins of the Maloideae. This subfamily of the Rosaceae includes a number of economically important fruit trees, such as apple and pear. When incubated with ortho-hydroxybenzoyl (salicoyl)-CoA, BIS catalyzes a single decarboxylative condensation with malonyl-CoA to form 4-hydroxycoumarin. A well-known anticoagulant derivative of this enzymatic product is dicoumarol. Elicitor-treated cell cultures of Sorbus aucuparia also formed 4-hydroxycoumarin when fed with the N-acetylcysteamine thioester of salicylic acid (salicoyl-NAC). BPS is the key enzyme of benzophenone metabolism. Polyprenylated benzophenone derivatives with bridged polycyclic skeletons are widely distributed in the Clusiaceae (Guttiferae). Xanthones are regioselectively cyclized benzophenone derivatives. BPS was converted into a functional phenylpyrone synthase (PPS) by a single amino acid substitution in the initiation/elongation cavity. The functional behavior of this Thr135Leu mutant was rationalized by homology modeling. The intermediate triketide may be redirected into a smaller pocket in the active site cavity, resulting in phenylpyrone formation by lactonization. PMID:19699497

Beerhues, Ludger; Liu, Benye

2009-08-21

320

The chemistry and preparation of tantalum complexes with 2,3-dihydroxy benzoic acid: experimental and theoretical investigation.  

PubMed

The effect of 2,3-dihydroxybenzoic acid (2,3DHBA, pyrocatechuic acid) on the chloro-alkoxo-species [TaCl(5-x)(OMe)(x)], formed by dissolving TaCl(5) in MeOH, has been studied. The coordination of 2,3DHBA-H(2)(-) on Ta (V) replacing MeO-terminal groups was monitored via NMR spectroscopy. The yellow solid 1 was isolated from the mixture of TaCl(5), with neutral 2,3-DHBA, in MeOH. From this solid the elemental (C, H and Ta), the thermogravimetric analyses, the IR, NMR, ESR and electronic spectra support the formula Ta(2)(2,3DHBA)(2)(O)(2)Cl(4)(MeO)(4). The ESR spectrum of solid 1, at 4.2 K, shows a half-field signal apart from a multiline signal around g=2, supporting evidence for semiquinone and Ta (IV) presence. The occurrence of superoxide radical, in the low temperature of ESR spectrum recording, cannot be ruled out. By heating the solid 1 at 500C, an oxide phase showing porous character (SEM) and retaining CO(2) (IR), is evident. Solid 1 heated at 900C, leads to the formation of ?-Ta(2)O(5) orthorhombic phase, as the XRD pattern indicates. The hydrolytic process of solid 1, in aqueous solutions, has been studied; the presence of paramagnetic species generated in situ upon addition of base and the consequent degradative process of 2,3-DHBA, under aerobic conditions is obvious. In order to gain information for the structure of solid 1, DFT calculations have been performed for some theoretical models, based on the empirical formula of solid 1. The calculated structural and spectroscopic parameters have been correlated to experimental results. The energy optimized structures may give an idea about the way of MeCl and MeOMe formation as well some possible intermediates of the hydrolytic mechanism. PMID:21216659

Hatzipanayioti, Despina; Kontotheodorou, Konstantinos

2010-12-07

321

The chemistry and preparation of tantalum complexes with 2,3-dihydroxy benzoic acid: Experimental and theoretical investigation  

NASA Astrophysics Data System (ADS)

The effect of 2,3-dihydroxybenzoic acid (2,3DHBA, pyrocatechuic acid) on the chloro-alkoxo-species [TaCl 5- x(OMe) x], formed by dissolving TaCl 5 in MeOH, has been studied. The coordination of 2,3DHBA-H 2- on Ta (V) replacing MeO-terminal groups was monitored via NMR spectroscopy. The yellow solid 1 was isolated from the mixture of TaCl 5, with neutral 2,3-DHBA, in MeOH. From this solid the elemental (C, H and Ta), the thermogravimetric analyses, the IR, NMR, ESR and electronic spectra support the formula Ta 2(2,3DHBA) 2(O) 2Cl 4(MeO) 4. The ESR spectrum of solid 1, at 4.2 K, shows a half-field signal apart from a multiline signal around g = 2, supporting evidence for semiquinone and Ta (IV) presence. The occurrence of superoxide radical, in the low temperature of ESR spectrum recording, cannot be ruled out. By heating the solid 1 at 500 C, an oxide phase showing porous character (SEM) and retaining CO 2 (IR), is evident. Solid 1 heated at 900 C, leads to the formation of ?-Ta 2O 5 orthorhombic phase, as the XRD pattern indicates. The hydrolytic process of solid 1, in aqueous solutions, has been studied; the presence of paramagnetic species generated in situ upon addition of base and the consequent degradative process of 2,3-DHBA, under aerobic conditions is obvious. In order to gain information for the structure of solid 1, DFT calculations have been performed for some theoretical models, based on the empirical formula of solid 1. The calculated structural and spectroscopic parameters have been correlated to experimental results. The energy optimized structures may give an idea about the way of MeCl and MeOMe formation as well some possible intermediates of the hydrolytic mechanism.

Hatzipanayioti, Despina; Kontotheodorou, Konstantinos

2011-03-01

322

Hydrogen bonding in the anhydrous 1:1 proton-transfer compounds of isonipecotamide with nitro-substituted benzoic acids: the salts of the three isomeric mononitrobenzoic acids and of 3,5-dinitrobenzoic acid.  

PubMed

The structures of the anhydrous 1:1 proton-transfer compounds of isonipecotamide (piperidine-4-carboxamide) with the three isomeric mononitro-substituted benzoic acids and with 3,5-dinitrobenzoic acid, namely 4-carbamoylpiperidinium 2-nitrobenzoate, (I), 4-carbamoylpiperidinium 3-nitrobenzoate, (II), and 4-carbamoylpiperidinium 4-nitrobenzoate, (III), all C(6)H(13)N(2)O(+)C(7)H(4)NO(4)(-), and 4-carbamoylpiperidinium 3,5-dinitrobenzoate, C(6)H(13)N(2)O(8)(+)C(7)H(3)N(2)O(6)(-), (IV), respectively, have been determined at 200?K. All the salts form hydrogen-bonded structures, viz. three-dimensional in (I), two-dimensional in (II) and (III), and one-dimensional in (IV). Featured in the hydrogen bonding of three of these [(I), (II) and (IV)] is the cyclic head-to-head amide-amide homodimer motif [graph set R(2)(2)(8)] through a duplex N-H...O association, the dimer then giving structure extension via either piperidinium or amide H-atom donors and carboxylate O-atom and, in some examples [(II) and (IV)], nitro O-atom acceptors. In (I), the centrosymmetric amide-amide homodimers are expanded laterally through N-H...O hydrogen bonds via cyclic R(4)(2)(8) interactions, forming ribbons which extend along the c cell direction. These ribbons incorporate the 2-nitrobenzoate cations through centrosymmetric cyclic piperidine-carboxylate N-H...O associations [graph set R(4)(4)(12)], giving interconnected sheets in the three-dimensional structure. In (II), in which no amide-amide homodimer is present, duplex piperidinium-amide N-H...O homomolecular hydrogen-bonding associations [graph set R(2)(2)(14)] give centrosymmetric head-to-tail dimers. Structure extension occurs through hydrogen-bonding associations between both the amide H-atom donors and carboxylate and nitro O-atom acceptors, as well as a three-centre piperidinium-carboxylate N-H...O,O' cyclic R(1)(2)(4) association, giving the two-dimensional network structure. In (III), the centrosymmetric amide-amide dimers are linked through the two carboxylate O-atom acceptors of the anions via bridging piperidinium N-H...O,O'...H-N(amide) hydrogen bonds, giving the two-dimensional sheet structure which features centrosymmetric cyclic R(4)(4)(12) associations. In (IV), the amide-amide dimer is also centrosymmetric, with the dimers linked to the anions through amide-nitro N-H...O interactions. The piperidinium groups extend the structure into one-dimensional ribbons via N-H...O(carboxylate) hydrogen bonds. The structures reported here further demonstrate the utility of the isonipecotamide cation in molecular assembly. They also highlight the efficacy of the cyclic R(2)(2)(8) amide-amide hydrogen-bonding homodimer motif in this process and provide an additional homodimer motif type in the head-to-tail R(2)(2)(14) association. PMID:21123896

Smith, Graham; Wermuth, Urs D

2010-11-19

323

40 CFR 721.1550 - Benzenediazonium, 4-(di-methyl-amino)-, salt with 2-hy-droxy-5-sul-fo-benzoic acid (1:1).  

Code of Federal Regulations, 2013 CFR

...Benzenediazonium, 4-(di-methyl-amino)-, salt with 2-hy-droxy-5-sul-fo-benzoic...Benzenediazonium, 4-(di-methyl-amino)-, salt with 2-hy-droxy-5-sul-fo-benzoic...benzenediazonium, 4-(dimethylamino)-, salt with...

2013-07-01

324

Bioavailability of phenolic acids  

Microsoft Academic Search

Two large classes of phenolic acids were comprised in this review: benzoic acid derivatives and cinnamic acid derivatives.\\u000a They have been found to be very extended in fruits and vegetables at different concentrations. For example, hydroxycinnamic\\u000a acids concentration was higher than that found for hydroxybenzoic acids. Concerning their consumption, hydroxycinnamic acids\\u000a provide larger contributions to the total polyphenol intake than

Sophie Lafay; Angel Gil-Izquierdo

2008-01-01

325

Investigation of the effects of 5-nitro-2-(3-phenylpropylamino)-benzoic acid (NPPB) on membrane currents in rat portal vein.  

PubMed Central

1. The effects of 5-nitro-2-(3-phenylpropylamino)-benzoic acid (NPPB) were investigated on evoked and spontaneous currents in freshly-isolated cells from the rat portal vein by use of conventional whole-cell recording and perforated-patch techniques. 2. At a holding potential of -60 mV in potassium-free, caesium-containing solutions, NPPB (10 microM) inhibited calcium (Ca)-sensitive chloride currents (ICl(Ca)) evoked by caffeine (10 mM) and by noradrenaline (10 microM) by 58% and 96%, respectively. 3. At a holding potential of -2 mV in potassium (K)-containing solutions, NPPB (10 microM) inhibited charybdotoxin-sensitive K-currents (IBK(Ca)) induced by noradrenaline (10 microM) and acetylcholine (10 microM) by approximately 90%. In contrast, IBK(Ca) induced by caffeine (10 mM) was unaffected in the presence of NPPB (10 microM). Conversely, IBK(Ca) elicited by caffeine (2 mM) was reduced by approximately 50% whereas IBK(Ca) evoked by noradrenaline (50 microM) was not significantly inhibited by NPPB. 4. In K-containing solutions, NPPB (10 microM) abolished spontaneous transient outward currents (STOCs) and induced a slowly-developing outward K-current. Bath application of glibenclamide (10 microM) abolished the outward current but did not antagonize the inhibitory effects of NPPB on STOCs or on IBK(Ca) evoked by noradrenaline. 5. In caesium-containing solutions, NPPB (30 microM) inhibited voltage-sensitive Ca-currents. 6. In Ca-free, K-containing solutions and in the presence of glibenclamide (5 microM), IBK(Ca) induced by 20 microM NS1619 was enhanced by NPPB (10 microM). 7. It is concluded that NPPB inhibits agonist-induced ICl(Ca) in rat portal vein smooth muscle. However, this agent also inhibits agonist-evoked IBK(Ca) and STOCs. Moreover, NPPB inhibits voltage-sensitive Ca-currents and stimulates a glibenclamide-sensitive K-current and IBK(Ca). The effects of this agent on evoked ICl(Ca) and IBK(Ca) and on STOCs probably involves an inhibitory action on intracellular Ca-stores.

Kirkup, A. J.; Edwards, G.; Weston, A. H.

1996-01-01

326

Glycidyl Esters of Aromatic Acids  

Microsoft Academic Search

The reaction of substituted benzoic acids, dicarboxylic acids such as phthalic, terephthalic, and isophthalic acids, and the sodium or potassium salts of these acids with equimolar or excess epichlorohydrin in the presence of benzyltrimethylammonium chloride has been studied using various solvents such as toluene, dioxane, monochlorobenzene, and tetrachloroethylene. Use of the free carboxylic acids gave only fair to low yields

Yoshio Tanaka; Hiroshi Kakiuchi

1967-01-01

327

4-({(Z)-5-[(Z)-3-Eth-oxy-4-hy-droxy-benzyl-idene]-3-methyl-4-oxo-1,3-thia-zolidin-2-yl-idene}amino)-benzoic acid dimethyl-formamide monosolvate  

PubMed Central

The molecular structure of the title compound, C20H18N2O5SC3H7NO, represents an essentially planar 5-benzylidene-thiazolidine moiety (r.m.s. deviation from planarity without ring substituents = 0.095?) to which the 4-aminobenzoic acid fragment is inclined at 76.23?(1). In the crystal, the benzoic acid molecules are arranged in layers parallel to [001] which are built up from inversion dimers held together by head-to-tail phenolcarboxy OH?O hydrogen bonds and head-to-tail ?? stacking interactions between the 5-benzylidene-thiazolidine moieties (ring centroid distance = 3.579?). These layers are separated by the dimethylformamide solvent molecules which are firmly anchored via a short OH?O hydrogen bond [O?O = 2.5529?(10)?] donated by the COOH group.

Kosma, Paul; Selzer, Edgar; Mereiter, Kurt

2012-01-01

328

Effect of Zanthoxylum xanthoxyloides and some substituted benzoic acids on glucose-6-phosphate and 6-phosphogluconate dehydrogenases in Hbss red blood cells.  

PubMed

The ether fraction of the aqueous extract of the roots of Zanthoxylum xanthoxyloides (antisickling fraction), vanillic acid, parahydroxybenzoic acid and paraflurobenzoic acid possess antisickling inhibitory activity at low concentrations. Paraflurobenzoic acid was the most active. When the activities of NADP+-linked glucose-6-phosphate and 6-phosphogluconate dehydrogenases in washed Hbss blood specimens treated with these agents (6 mg/ml for antisickling fraction and 6 micrograms/ml for the acids) were compared with controls in vitro, there were no significant differences in either normal or sickled states. The media were devoid of enzyme activity. These agents neither affect the activities of these enzymes while exhibiting antisickling activity nor disrupt the cell membrane to the extent of causing leakage to the media. PMID:2615418

Osoba, O A; Adesanya, S A; Durosimi, M A

1989-11-01

329

One-pot high-temperature synthesis of polyimides in molten benzoic acid: Kinetics of reactions modeling stages of polycondensation and cyclization  

Microsoft Academic Search

For aromatic and aliphatic diamines of significantly different basicities, the kinetics of acylation with phthalic anhydride\\u000a in glacial acetic acid in the range 1670?C and of imidization of corresponding bis(o-carboxyamides) in acetic acid at 140?C has been studied. The reactions under study model the stages of polycondensation and\\u000a intramolecular cyclization, respectively, in the high-temperature catalytic synthesis of polyimides in molten

A. A. Kuznetsov; A. Yu. Tsegelskaya; P. V. Buzin

2007-01-01

330

Inhibition of soluble epoxide hydrolase by cis-4-[4-(3-adamantan-1-yl-ureido)cyclohexyl-oxy]benzoic acid exhibits antihypertensive and cardioprotective actions in transgenic rats with angiotensin II-dependent hypertension  

PubMed Central

The present study was undertaken to evaluate the effects of chronic treatment with cis-4-[4-(3- adamantan-1-yl-ureido)cyclohexyl-oxy]benzoic acid (c-AUCB), a novel inhibitor of soluble epoxide hydrolase (sEH), which is responsible for the conversion of biologically active epoxyeicosatrienoic acids (EETs) to biologically inactive dihydroxyeicosatrienoic acids (DHETEs), on blood pressure (BP) and myocardial infarct size in male heterozygous Ren-2 transgenic rats (TGR) with established hypertension. Normotensive Hannover Sprague-Dawley (HanSD) rats served as controls. Myocardial ischemia was induced by coronary artery occlusion. Systolic BP was measured in conscious animals by tail-plethysmography. c-AUCB was administrated in drinking water. Renal and myocardial concentrations of EETs and DHETEs served as markers of internal production of epoxygenase metabolites. Chronic treatment with c-AUCB, which resulted in significant increases in the availability of biologically active epoxygenase metabolites in TGR assessed as the ratio of EETs/DHETEs was accompanied by a significant reduction in BP and significantly reduced infarct size in TGR as compared with untreated TGR. The cardioprotective action of c-AUCB treatment was completely prevented by acute administration of a selective EETs antagonist (14,15-epoxyeicosa5(Z)-enoic acid), supporting the notion that the improved cardiac ischemic tolerance conferred by sEH inhibition is mediated by EETs actions at the cellular level. These findings indicate that chronic inhibition of sEH exhibits antihypertensive and cardioprotective actions in this transgenic model of angiotensin II-dependent hypertension.

Neckar, Jan; Kopkan, Libor; Huskova, Zuzana; Kolar, Frantisek; Papousek, Frantisek; Kramer, Herbert J.; Hwang, Sung Hee; Hammock, Bruce D.; Imig, John D.; Maly, Jiri; Netuka, Ivan; Ost'adal, Bohuslav; Cervenka, Ludek

2012-01-01

331

40 CFR 721.1550 - Benzenediazonium, 4-(di-methyl-amino)-, salt with 2-hy-droxy-5-sul-fo-benzoic acid (1:1).  

Code of Federal Regulations, 2010 CFR

(1) The chemical substance identified as benzenediazonium, 4-(dimethylamino)-, salt with 2-hydroxy-5-sulfobenzoic acid (1:1) (CAS No. 124737-31-1) (P-90-1366) is subject to reporting under this section for the significant new uses described in paragraph (a)(2) of this...

2009-07-01

332

Synthesis, spectroscopic, crystal structure and DNA binding of Ru(II) complexes with 2-hydroxy-benzoic acid [1-(4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)-ethylidene]-hydrazide  

NASA Astrophysics Data System (ADS)

Reactions of 2-hydroxy-benzoic acid [1-(4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)-ethylidene]-hydrazide (H 2L) with [RuHCl(CO)(EPh 3) 3] (E = P or As) were carried out and the new complexes obtained were characterized by elemental analysis, electronic, IR, 1H NMR and 13C NMR spectroscopic techniques and single crystal X-ray diffraction studies. Complex ( 1) crystallizes in the monoclinic space group P2(1)/ c with unit cell dimensions a = 18.6236(17) , b = 12.8627(12) , c = 21.683(2) , ? = 90.00, ? = 114.626(2), ? = 90.00 V = 4721.8(8) , Z = 4. The crystal structure of the complex shows Ru(II) atom is six-coordinated, forming a slightly distorted octahedral geometry with two P atoms in axial positions, and three chelating donor atoms of the tridentate Schiff base ligand and one carbonyl group located in the equatorial plane. The molecular structure is stabilized by intramolecular OHN interactions. No intermolecular hydrogen bond was observed. The intramolecular hydrogen bond exists between the oxygen atom from salicylic acid moiety and nitrogen from the same moiety. A variety of solution studies were carried out for the determination of DNA binding mode of the complexes. The results suggest that both complexes bind to Herring sperm DNA via non intercalative mode.

Chitrapriya, Nataraj; Sathiya Kamatchi, Thangavel; Zeller, Matthias; Lee, Hyosun; Natarajan, Karuppannan

2011-10-01

333

The co-crystal N,N?-bis-[(pyridin-1-ium-2-yl)meth-yl]ethane-dithio-amide bis-(2,6-di-nitro-benzoate)-2,6-di-nitro-benzoic acid (1/4)  

PubMed Central

The asymmetric unit of title co-crystal, C14H16N4S2 2+2C7H3N2O6 ?4C7H4N2O6, comprises a centrosymmetric dipyridinium dication, a 2,6-dinitrobenzoate anion and two independent 2,6-dinitrobenzoic acid molecules. The pyridinium rings are each approximately perpendicular to the central dithioamide unit [dihedral angle = 80.67?(12)]. The carboxylate/carboxylic acid groups are approximately perpendicular to the benzene ring to which they are attached [dihedral angles = 78.85?(16), 81.46?(19) and 71.28?(15)]. By contrast, the major twist exhibited by a nitro group is manifested in a dihedral angle of 32.66?(17). The most prominent feature of the crystal packing is linear supramolecular chains along [1-10], featuring OH?O(carboxylate) and pyridinium-NH?O hydrogen bonds. These are consolidated into a three-dimensional architecture by thioamidenitro NH?O, CH?O and ?? [inter-centroid distance = 3.524?(2)?] interactions. One of the nitro O atoms was refined over two sites; the major site was 0.65?(7) occupied.

Arman, Hadi D.; Miller, Tyler; Poplaukhin, Pavel; Tiekink, Edward R. T.

2013-01-01

334

Modeling, Synthesis and Biological Evaluation of Potential Retinoid-X-Receptor (RXR) Selective Agonists: Novel Halogenated Analogs of 4-[1-(3,5,5,8,8-Pentamethyl-5,6,7,8-tetrahydro-2-naphthyl)ethynyl]benzoic Acid (Bexarotene)  

PubMed Central

The synthesis of halogenated analogs of 4-[1-(3,5,5,8,8-pentamethyl-5,6,7,8-tetrahydro-2-naphthyl)ethynyl]benzoic acid (1), known commonly as bexarotene, and their evaluation for retinoid-X-receptor (RXR)-specific agonist performance is described. Compound 1 is FDA approved to treat cutaneous T-cell lymphoma (CTCL); however, bexarotene treatment can induce hypothyroidism and elevated triglyceride levels, presumably by disrupting RXR heterodimer pathways for other nuclear receptors. The novel halogenated analogs in this study were modeled and assessed for their ability to bind to RXR and stimulate RXR homodimerization in an RXRE-mediated transcriptional assay as well as an RXR mammalian-2-hybrid assay. In an array of 8 novel compounds, 4 analogs were discovered to promote RXR-mediated transcription with comparable EC50 values as 1 and are selective RXR agonists. Our approach also uncovered a periodic trend of increased binding and homodimerization of RXR when substituting a halogen atom for a proton ortho to the carboxylic acid on 1.

Furmick, Julie K.; Kaneko, Ichiro; Walsh, Angela N.; Yang, Joanna; Bhogal, Jaskaran S.; Gray, Geoffrey M.; Baso, Juan C.; Browder, Drew O.; Prentice, Jessica L.S.; Montano, Luis A.; Huynh, Chanh C.; Marcus, Lisa M.; Tsosie, Dorian G.; Kwon, Jungeun S.; Quezada, Alexis; Reyes, Nicole M.; Lemming, Brittney; Saini, Puneet; van der Vaart, Arjan; Groy, Thomas L.; Marshall, Pamela A.; Jurutka, Peter W.; Wagner, Carl E.

2012-01-01

335

The co-crystal N,N'-bis-[(pyridin-1-ium-2-yl)meth-yl]ethane-dithio-amide bis-(2,6-di-nitro-benzoate)-2,6-di-nitro-benzoic acid (1/4).  

PubMed

The asymmetric unit of title co-crystal, C14H16N4S2 (2+)2C7H3N2O6 (-)4C7H4N2O6, comprises a centrosymmetric dipyridinium dication, a 2,6-di-nitro-benzoate anion and two independent 2,6-di-nitro-benzoic acid mol-ecules. The pyridin-ium rings are each approximately perpendicular to the central di-thio-amide unit [dihedral angle = 80.67?(12)]. The carboxyl-ate/carb-oxy-lic acid groups are approximately perpendicular to the benzene ring to which they are attached [dihedral angles = 78.85?(16), 81.46?(19) and 71.28?(15)]. By contrast, the major twist exhibited by a nitro group is manifested in a dihedral angle of 32.66?(17). The most prominent feature of the crystal packing is linear supra-molecular chains along [1-10], featuring O-H?O(carboxyl-ate) and pyridinium-N-H?O hydrogen bonds. These are consolidated into a three-dimensional architecture by thio-amide-nitro N-H?O, C-H?O and ?-? [inter-centroid distance = 3.524?(2)?] inter-actions. One of the nitro O atoms was refined over two sites; the major site was 0.65?(7) occupied. PMID:24098201

Arman, Hadi D; Miller, Tyler; Poplaukhin, Pavel; Tiekink, Edward R T

2013-09-04

336

Quantitation of Flavanols, Proanthocyanidins, Isoflavones, Flavanones, Dihydrochalcones, Stilbenes, Benzoic Acid Derivatives Using Ultraviolet Absorbance after Identification by Liquid Chromatography-Mass Spectrometry.  

PubMed

A general method was developed for the systematic quantitation of flavanols, proanthocyanidins, isoflavones, flavanones, dihydrochalcones, stilbenes, and hydroxybenzoic acid derivatives (mainly hydrolyzable tannins) based on UV band II absorbance arising from the benzoyl structure. The compound structures and the wavelength maximum were well correlated and were divided into four groups: the flavanols and proanthocyanidins at 278 nm, hydrolyzable tannins at 274 nm, flavanones at 288 nm, and isoflavones at 260 nm. Within each group, molar relative response factors (MRRFs) were computed for each compound based on the absorbance ratio of the compound and the group reference standard. Response factors were computed for the compounds as purchased (MRRF), after drying (MRRF(D)), and as the best predicted value (MRRF(P)). Concentrations for each compound were computed based on calibration with the group reference standard and the MRRF(P). The quantitation of catechins, proanthocyanidins, and gallic acid derivatives in white tea was used as an example. PMID:22577798

Lin, Long-Ze; Harnly, James M

2012-06-01

337

Tetra-?-benzoato-?4 O:O?;?3 O:O,O?;?3 O,O?:O?-bis-[(benzoato-?2 O,O?)(1,10-phenanthroline-?2 N,N?)terbium(III)] benzoic acid disolvate  

PubMed Central

The asymmetric unit of the title complex, [Tb2(C7H5O2)6(C12H8N2)2]2C7H6O2, consists of one-half of the complex molecule, which lies on a crystallographic inversion centre, and one benzoic acid solvent molecule. The two TbIII ions are linked by four bridging benzoate ions, with a Tb?Tb distance of 3.9280?(6)?. Additionally, each TbIII ion is coordinated by one phenanthroline heterocycle and a bidentate benzoate ion. The irregular nine-coordinated geometry of the TbIII ion is composed of seven O and two N atoms. The molecular structure is stabilized by intramolecular CH?O hydrogen bonds. In the crystal structure, molecules are linked into chains along the a axis by intermolecular CH?O hydrogen bonds. The crystal structure is further stabilized by intermolecular CH?O and CH?? interactions. Weak ?? interactions are also observed [centroidcentroid distances = 3.6275?(14)3.6604?(14)?].

Ooi, Ping Howe; Teoh, Siang Guan; Yeap, Chin Sing; Fun, Hoong-Kun

2010-01-01

338

Modeling, Synthesis and Biological Evaluation of Potential Retinoid-X-Receptor (RXR) Selective Agonists: Novel Analogs of 4-[1-(3,5,5,8,8- Pentamethyl-5,6,7,8-tetrahydro-2- naphthyl)ethynyl]benzoic Acid (Bexarotene)  

PubMed Central

This report describes the synthesis of analogs of 4-[1-(3,5,5,8,8-pentamethyl-5,6,7,8-tetrahydro-2-naphthyl)ethynyl]benzoic acid (1), commonly known as bexarotene, and their analysis in acting as retinoid-X-receptor (RXR)-specific agonists. Compound 1 has FDA approval to treat cutaneous T-cell lymphoma (CTCL); however, its use can cause side effects such as hypothyroidism and increased triglyceride concentrations, presumably by disruption of RXR heterodimerization with other nuclear receptors. The novel analogs in the present study have been evaluated for RXR activation in an RXR mammalian-2-hybrid assay as well as an RXRE-mediated transcriptional assay, and for their ability to induce apoptosis, as well as for their mutagenicity and cytotoxicity. Analysis of 11 novel compounds revealed the discovery of 3 analogs that best induce RXR-mediated transcriptional activity, stimulate apoptosis, have comparable Ki and EC50 values to 1, and are selective RXR agonists. Our experimental approach suggests that rational drug design can develop new rexinoids with improved biological properties.

Wagner, Carl E.; Jurutka, Peter W.; Marshall, Pamela A.; Groy, Thomas L.; van der Vaart, Arjan; Ziller, Joseph W.; Furmick, Julie K.; Graeber, Mark E.; Matro, Erik; Miguel, Belinda V.; Tran, Ivy T.; Kwon, Jeng Eun S.; Tedeschi, Jamie N.; Moosavi, Shahram; Danishyar, Amina; Philp, Joshua S.; Khamees, Reina O.; Jackson, Jevon N.; Grupe, Darci K.; Badshah, Syed L.; Hart, Justin W.

2009-01-01

339

3,5-Dimethoxy-4-(3-(2-carbonyl-ethyldisulfanyl)-propionyl)-benzoic acid 4-guanidino-butyl ester: a novel twin drug that prevents primary cardiac myocytes from hypoxia-induced apoptosis.  

PubMed

Leonurine possesses cardioprotective effects in myocardial ischemia due to its anti-apoptotic properties. However, the process to isolate and purify leonurine is difficult, because of its low content in the Herb Leonuri and its impurity. Moreover, the high dosage used indicates low potency of leonurine. To overcome these defects, we had synthesized a novel twin drug of leonurine, 3,5-dimethoxy-4-(3-(2-carbonyl-ethyldisulfanyl)-propionyl)-benzoic acid 4-guanidino-butyl ester (compound 2). In this paper, we focused on investigating the cardioprotective effect and underlying mechanisms of compound 2. Our data showed that cell viability was significantly increased in a dose-dependent manner and the levels of lactate dehydrogenase (LDH) and creatine kinase (CK) were also significantly attenuated in the compound 2-treated group. In addition, we observed the cardioprotective effects by Hoechst 33258 nucleus staining, JC-1 staining, Annexin V-FITC/PI staining and transmission electron microscopy. Compound 2 inhibited apoptosis by reducing the ratio of Bcl-2/Bax, decreasing cleaved-caspase-3 expression and enhancing the phosphorylation of Akt. Furthermore, the phosphorylation effect of compound 2 was reversed by LY294002 the phosphatidylinositol-3-kinase (PI3K) inhibitor from happening. We concluded that compound 2 played a cardioprotective role in hypoxia-induced primary cardiac myocytes apoptosis partly via modulating the PI3K/Akt pathway at a 10-fold lower concentration than leonurine. PMID:23305837

Liu, Chunhua; Guo, Wei; Maerz, Stefanie; Gu, Xianfeng; Zhu, Yizhun

2013-01-07

340

Relationships between Phenolic Acid Concentrations, Transpiration, Water Utilization, Leaf Area Expansion, and Uptake of Phenolic Acids: Nutrient Culture Studies  

Microsoft Academic Search

Phenolic acid treatments of cucumber seedlings (Cucumis sativus cv Early Green Cluster) inhibited transpiration, water utilization, leaf area, and absolute and relative rates of leaf expansion. The cinnamic acids, ferulic and p-coumaric acids, were two to five times more inhibitory than the benzoic acids, p-hydroxybenzoic acid and vanillic acid. When phenolic acid concentrations were maintained at inhibitory concentrations through multiple

Udo Blum; Thomas M. Gerig

2005-01-01

341

Synthesis and mesomorphic properties of some 3-substituted-4-cyanophenyl esters, 4?-cyano-3-substituted-4-biphenyl esters of 4-(trans-4-alkylcyclohexyl) benzoic, 4-alkyl-3-substituted biphenyl-4?-carboxylic, trans-4-alkylcyclohexanecarboxylic and 4-alkylbenzoic acids and electrooptic parameters of liquid-crystalline mixtures containing these compounds  

Microsoft Academic Search

The reaction of trans-4-alkylcyclohexanecarboxylic acid chlorides, 4-alkylbenzoic, 4-(trans-4-alkylcyclohexyl)-benzoic, 4-alkyl-3-substituted biphenyl-4?-carboxylic acids (I) with 4-hydroxy-3?-substituted benzonitriles (IIa-d) and 4-hydroxy-3?-substituted-4?-cyanobiphenyls (IIe and g) has produced the corresponding esters (IIIa-v). The mesomorphic properties of the esters and electrooptic and dynamic parameters of the mixtures containing these compound have been studied. It has been shown that the liquid-crystalline mixtures containing 4-cyano-3-substituted-4?-biphenyl esters of 4-alkylbenzoic

V. S. Bezborodov; V. I. Lapanik; P. V. Adomenas; R. Sirutkaitis

1992-01-01

342

1,2-Bis(pyridin-4-yl)diazene-3,4,5-trihy-droxy-benzoic acid-methanol (3/2/2)  

PubMed Central

The title compound, 3C10H8N42C7H6O52CH4O, has a molecular crystal structure which results from the cocrystallization of gallic acid (GA), 4,4?-azodipyridine (AzPy) and methanol in a 2:3:2 molar ratio. The asymmetric unit comprises one molecule each of GA, AzPy and methanol in general positions and half a molecule of AzPy as this is located about a centre of inversion. In the crystal, all the components of the structure are associated via the extended system of hydrogen bonds (OH?O and OH?N) and ?? stacking interactions [centroidcentroid distance = 3.637?(3)?] into two-dimensional supramolecular layers which are packed parallel to the [101] plane. The shortest perpendicular distance and the slippage between aromatic groups are 3.395?(3) and 2.152?(3)?, respectively. The AzPy molecules display a trans conformation with respect to the azo groups.

Rusu, Elena; Shova, Sergiu; Rusu, Gheorghe

2012-01-01

343

Metabolism of aromatic acids in the antibiotic-producing basidiomycete Oudemansiella mucida.  

PubMed

Aromatic acids were determined in the mycelium and fermentation medium of Oudemansiella mucida. Coumaric acids (both m- and p-), p-hydroxybenzoic acid (salicylic acid) and benzoic acid were found to predominate in the mycelium. Phenylacetic acid represents the main component in the medium. Phenylalanine ammonia-lyase catalyzing conversion of phenylalanine to cinnamic acid which is further metabolized to benzoic acid was detected in the mycelium. The results are discussed with respect to the synthesis of the antibiotic mucidin. PMID:7173747

Zouchov, Z; Wurst, M; Nerud, F; Muslek, V

1982-01-01

344

Five new Zn(II) and Cd(II) coordination polymers constructed by 3,5-bis-oxyacetate-benzoic acid: Syntheses, crystal structures, network topologies and luminescent properties  

NASA Astrophysics Data System (ADS)

Five Zn(II) and Cd(II) coordination polymers, [Zn2(BOABA)(bpp)(OH)]0.5H2O (1), [Cd3(BOABA)2(bpp)2(H2O)6]2H2O (2), [Cd3(BOABA)2(2,2?-bipy)3(H2O)4]5.5H2O (3), [CdNa(BOABA)(H2O)]2H2O (4) and [Cd2(BOABA)(bimb)Cl(H2O)2]H2O (5) (H3BOABA=3,5-bis-oxyacetate-benzoic acid, bpp=1,3-bi(4-pyridyl)propane, 2,2?-bipy=2,2?-bipyridine, bimb=1,4-bis(imidazol-1?-yl)butane), have been solvothermally synthesized and characterized by single-crystal X-ray diffraction, elemental analyses, IR spectra and TG analyses. 1 is an uninodal 4-connected 2D square grid network based on binuclear zinc clusters. 2 is 2D wavelike layer structure and further linked by hydrogen bonds into the final 3D (5,6,6)-connected topology network. 3 is 3-connected 2D topology network and the 2,2?-bipy ligands decorate in two different types. 4 is a (4,8)-connected 2D topology network with heterocaryotic {Cd2Na2} clusters and BOABA3- ligands. 5 can be rationalized as a (3,10)-connected 3D topology network with tetranuclear {Cd4Cl2} clusters and BOABA3- ligands. Meanwhile, photoluminescence studies revealed that these five coordination polymers display strong fluorescent emission bands in the solid state at room temperature.

Jiang, Xian-Rong; Yuan, Hong-Yan; Feng, Yun-Long

2012-07-01

345

The ground-state tunneling splitting of various carboxylic acid dimers  

Microsoft Academic Search

Carboxylic acid dimers in gas phase reveal ground-state tunneling splittings due to a double proton transfer between the two subunits. In this study we apply a recently developed accurate semiclassical method to determine the ground-state tunneling splittings of eight different carboxylic acid derivative dimers (formic acid, benzoic acid, carbamic acid, fluoro formic acid, carbonic acid, glyoxylic acid, acrylic acid, and

Christofer S. Tautermann; Andreas F. Voegele; Klaus R. Liedl

2004-01-01

346

Alteration of the phospho- or neutral lipid content and fatty acid composition in Listeria monocytogenes due to acid adaptation mechanisms for hydrochloric, acetic and lactic acids at pH 5.5 or benzoic acid at neutral pH  

Microsoft Academic Search

This study provides a first approach to observe the effects on Listeria monocytogenes of cellular exposure to acid stress at low or neutral pH, notably how phospho- or neutral lipids are involved in this mechanism,\\u000a besides the fatty acid profile alteration. A thorough investigation of the composition of polar and neutral lipids from L. monocytogenes grown at pH 5.5 in

Sofia K. Mastronicolis; Anita Berberi; Ioannis Diakogiannis; Evanthia Petrova; Irene Kiaki; Triantafillia Baltzi; Polydoros Xenikakis

2010-01-01

347

Pure manganese(III) 5,10,15,20-tetrakis(4-benzoic acid)porphyrin (MnTBAP) is not a superoxide dismutase mimic in aqueous systems: a case of structureactivity relationship as a watchdog mechanism in experimental therapeutics and biology  

Microsoft Academic Search

Superoxide is involved in a plethora of pathological and physiological processes via oxidative stress and\\/or signal transduction\\u000a pathways. Superoxide dismutase (SOD) mimics have, thus, been actively sought for clinical and mechanistic purposes. Manganese(III)\\u000a 5,10,15,20-tetrakis(4-benzoic acid)porphyrin (MnTBAP) is one of the most intensely explored SOD mimics in biology and medicine.\\u000a However, we show here that this claimed SOD activity of MnTBAP

Jlio S. Rebouas; Ivan Spasojevi?; Ines Batini?-Haberle

2008-01-01

348

4-(Imidazol-1-yl)benzoic acid  

PubMed Central

In the title molecule, C10H8N2O2, the imidazole and benzene rings form a dihedral angle of 14.5?(1). In the crystal, intermolecular OH?N hydrogen bonds link the molecules into chains extending in [01], which are further linked into sheets parallel to (102) through weak CH?O interactions.

Zheng, Zheng; Geng, Wen-Qian; Wu, Zhi-Chao; Zhou, Hong-Ping

2011-01-01

349

Biosynthesis and metabolism of salicylic acid  

SciTech Connect

Pathways of salicylic acid (SA) biosynthesis and metabolism in tobacco have been recently identified. SA, an endogenous regulator of disease resistance, is a product of phenylpropanoid metabolism formed via decarboxylation of trans-cinnamic acid to benzoic acid and its subsequent 2-hydroxylation to SA. In tobacco mosaic virus-inoculated tobacco leaves, newly synthesized SA is rapidly metabolized to SA O-{beta}-D-glucoside and methyl salicylate. Two key enzymes involved in SA biosynthesis and metabolism: benzoic acid 2-hydroxylase, which converts benzoic acid to SA, and UDPglucose:SA glucosyltransferase (EC 2.4.1.35), which catalyzes conversion of SA to SA glucoside have been partially purified and characterized. Progress in enzymology and molecular biology of SA biosynthesis and metabolism will provide a better understanding of signal transduction pathway involved in plant disease resistance. 62 refs., 1 fig.

Lee, H.; Leon, J.; Raskin, I. [Rutgers Univ., New Brunswick, NJ (United States)

1995-05-09

350

Solid-phase extraction of acidic herbicides.  

PubMed

A discussion of solid-phase extraction method development for acidic herbicides is presented that reviews sample matrix modification, extraction sorbent selection, derivatization procedures for gas chromatographic analysis, and clean-up procedures for high-performance liquid chromatographic analysis. Acidic herbicides are families of compounds that include derivatives of phenol (dinoseb, dinoterb and pentachlorophenol), benzoic acid (acifluorfen, chloramben, dicamba, 3,5-dichlorobenzoic acid and dacthal--a dibenzoic acid derivative), acetic acid [2,4-dichlorophenoxyacetic acid (2,4-D), 4-chloro-2-methylphenoxyacetic acid (MCPA) and 2,4,5-trichlorophenoxyacetic acid (2,4,5-T)], propanoic acid [dichlorprop, fluazifop, haloxyfop, 2-(4-chloro-2-methylphenoxy)propanoic acid (MCPP) and silvex], butanoic acid [4-(2,4-dichlorophenoxy)butanoic acid (2,4-DB) and 4-(4-chloro-2-methylphenoxy)butanoic acid (MCPB)], and other miscellaneous acids such as pyridinecarboxylic acid (picloram) and thiadiazine dioxide (bentazon). PMID:10941675

Wells, M J; Yu, L Z

2000-07-14

351

Monocarboxylic acid permeation through lipid bilayer membranes  

Microsoft Academic Search

Summary The membrane permeability coefficients for the homologous monocarboxylic acids, formic through hexanoic, as well as benzoic and salicylic, were determined for egg phosphatidylcholine-decane planar bilayer membranes. The permeabilities of formic, acetic and propionic acid were also determined for solvent-free phosphatidylethanolamine bilayers. Permeability coefficients were calculated from tracer fluxes measured under otherwise symmetrical conditions, and precautions were taken to ensure

Anne Walter; John Gutknecht

1984-01-01

352

Mycophenolic Acid  

Center for Drug Evaluation (CDER)

... Publications on Genomics. -. Mycophenolic Acid. Pharmacogenomic Information. ... Mycophenolic Acid, Transplantation, HGPRT, Precautions. ... More results from www.fda.gov/drugs/scienceresearch/researchareas

353

Acid rain  

Microsoft Academic Search

Acid precipitation is a global problem. The effects were first seen in Europe; it affects the Great Lakes and the Midwest because higher-than-normal levels of acidity in rain are found in these areas. Several bays of the Great Lakes are now known to receive substantial runoff from freshwater streams that have been made acidic by acid rains. These areas may

1979-01-01

354

Transcellular Transport of Benzole Acid Across Caco-2 Cells by a pH-Dependent and Carrier-Mediated Transport Mechanism  

Microsoft Academic Search

The pH-dependent transcellular transport of [14 C]benzoic acid across a Caco-2 cell monolayer is shown to be mediated by a monocarboxylic acid-specific carrier-mediated transport system, localized on the apical membrane. Evidence for the carrier-mediated transport of benzoic acid includes (a) the significant temperature and concentration dependence, (b) the metabolic energy dependence, (c) the inhibition by unlabeled benzoic acid and other

Akira Tsuji; Hitomi Takanaga; Ikumi Tamai; Tetsuya Terasaki

1994-01-01

355

Biosynthesis and Metabolism of Salicylic Acid  

Microsoft Academic Search

Pathways of salicylic acid (SA) biosynthesis and metabolism in tobacco have been recently identified. SA, an endogenous regulator of disease resistance, is a product of phenylpropanoid metabolism formed via decarboxylation of trans-cinnamic acid to benzoic acid and its subsequent 2-hydroxylation to SA. In tobacco mosaic virus-inoculated tobacco leaves, newly synthesized SA is rapidly metabolized to SA O-beta-D-glucoside and methyl salicylate.

Hyung-Il Lee; Jose Leon; Ilya Raskin

1995-01-01

356

Acid rain  

SciTech Connect

A series of definitions for the field of acid rain studies are presented. Protocols for acid rain sampling and monitoring are also presented. A procedure for calculatory precipitation pH is discussed. 11 references, 1 table.

Stensland, G.J.

1983-11-01

357

Oleanolic acid.  

PubMed

Oleanolic acid (3?-hydroxyolean-12-en-28-oic acid) is a pentacyclic triterpenoid compound with a widespread occurrence throughout the plant kingdom. In nature, the compound exists either as a free acid or as an aglycone precursor for triterpenoid saponins, in which it can be linked to one or more sugar chains. Oleanolic acid and its derivatives possess several promising pharmacological activities, such as hepatoprotective effects, and anti-inflammatory, antioxidant, or anticancer activities. With the recent elucidation of its biosynthesis and the imminent commercialization of the first oleanolic acid-derived drug, the compound promises to remain important for various studies. In this review, the recent progress in understanding the oleanolic acid biosynthesis and its pharmacology are discussed. Furthermore, the importance and potential application of synthetic oleanolic acid derivatives are highlighted, and research perspectives on oleanolic acid are given. PMID:22377690

Pollier, Jacob; Goossens, Alain

2012-02-28

358

Aminocaproic Acid  

MedlinePLUS

Aminocaproic acid is used to control bleeding that occurs when blood clots are broken down too quickly. This type ... the baby is ready to be born). Aminocaproic acid is also used to control bleeding in the ...

359

Ethacrynic Acid  

MedlinePLUS

Ethacrynic acid, a 'water pill,' is used to treat swelling and fluid retention caused by various medical problems. It ... Ethacrynic acid comes as a tablet to take by mouth. It is usually taken once or twice a day ...

360

Acid Reflux  

MedlinePLUS

... end of the esophagus called the lower esophageal sphincter or LES keeps the acid in the stomach ... moderately symptomatic GERD. These drugs increase lower esophageal sphincter pressure, which helps prevent acid reflux, and improves ...

361

Acidizing method  

SciTech Connect

A method is described for acidizing a subterranean formation, comprising the steps of: (a) forming an acidizing composition by mixing an aqueous acid component with at least one water-soluble organosilicon compound; and (b) injecting the composition into the formation.

Watkins, D.R.; Kalfayan, L.J.; Hewgill, G.S.

1987-03-03

362

Pathway of salicylic acid biosynthesis in healthy and virus-inoculated tobacco  

SciTech Connect

Salicylic acid (SA) is a likely endogenous regulator of localized and systemic disease resistance in plants. During the hypersensitive response of Nicotiana tabacum L. cv Xanthi-nc to tobacco mosaic virus (TMV), SA levels rise dramatically. We studied Sa biosynthesis in healthy and TMV-inoculated tobacco by monitoring the levels of SA and its likely precursors in extracts of leaves and cell suspensions. In TMV-inoculated leaves, stimulation of Sa accumulation is accompanied by a corresponding increase in the levels of benzoic acid. [sup 14]C-Tracer studies with cell suspensions and mock- or TMV-inoculated leaves indicate that the label moves from trans-cinnamic acid to SA via benzoic acid. In healthy and TMV-inoculated tobacco leaves, benzoic acid induced SA accumulation. o-Coumaric acid, which was previously reported as a possible precursor of SA in other species, did not increase SA levels in tobacco. In healthy tobacco tissue, the specific activity of newly formed SA was equal to that of the supplied [[sup 14]C] benzoic acid, whereas in TMV-inoculated leaves some isotope dilution was observed, presumably because of the increase in the pool of endogenous benzoic acid. We observed accumulation of pathogenesis-related-1 proteins and increased resistance to TMV in benzoic acid but no in 0-coumaric acid-treated tobacco leaves. This is consistent with benzoic acid being the immediate precursor of SA. We conclude that in healthy and virus-inoculated tobacco, SA is formed from cinnamic acid via benzoic acid. 27 refs., 7 figs., 1 tab.

Yalpani, N.; Leon, J.; Lawton, M.A.; Raskin, I. (Rutgers Univ., New Brunswick, NJ (United States))

1993-10-01

363

Gallic acid pyridine monosolvate  

PubMed Central

In the title compound (systenatic name: 3,4,5-trihydroxybenzoic acid pyridine monosolvate), C5H5NC7H6O5, the gallic acid molecule is essentially planar (r.m.s deviation = 0.0766? for non-H atoms) and is linked to the pyridine molecule by an OH?N hydrogen bond. An intramolecular OH?O hydrogen bond occurs in the gallic acid molecule. The gallic acid and pyridine mean planes make a dihedral angle 12.6?(3). Intermolecular OH?O and OH?N hydrogen bonding involving the hydroxy and carboxyl groups and the pyridine molecule, and ?? interactions between inversion-related pyridines [centroidcentroid distance = 3.459?(6)?] and between pyridine and benzene rings [centroidcentroid distance = 3.548?(6)?], lead to a three-dimensional network in the crystal.

Dong, Fu-Yue; Wu, Jie; Tian, Hai-Yan; Ye, Qing-Mei; Jiang, Ren-Wang

2011-01-01

364

Pyrolysis Mechanisms of Aromatic Carboxylic Acids  

SciTech Connect

Although decarboxylation of carboxylic acids is widely used in organic synthesis, there is limited mechanistic information on the uncatalyzed reaction pathways of aromatic carboxylic acids at 300-400 {degrees} C. The pyrolysis mechanisms of 1,2-(3,3-dicarboxyphenyl)ethane, 1,2-(4,4-dicarboxylphenyl)ethane, 1-(3-carboxyphenyl)-2-(4- biphenyl)ethane, and substituted benzoic acids have been investigated at 325-425 {degrees} C neat and diluted in an inert solvent. Decarboxylation is the dominant pyrolysis path. Arrhenius parameters, substituent effects, and deuterium isotope effects are consistent with decarboxylation by an electrophilic aromatic substitution reaction. Pyrolysis of benzoic acid in naphthalene, as a solvent, produces significant amounts of 1- and 2-phenylnaphthalenes. The mechanistic pathways for decarboxylation and arylation with be presented.

Britt, P.F.; Eskay, T.P.; Buchanan, A.C. III

1997-12-31

365

Basically Acids  

NSDL National Science Digital Library

Students learn the basics of acid/base chemistry in a fun, interactive way by studying instances of acid/base chemistry found in popular films such as Harry Potter and the Prisoner of Azkaban and National Treasure. Students learn what acids, bases and indicators are and how they can be used, including invisible ink. They also learn how engineers use acids and bases every day to better our quality of life. Students' interest is piqued by the use of popular culture in the classroom.

University Of Houston

366

Identification of Lactic Acid Bacteria from Chili Bo, a Malaysian Food Ingredient  

Microsoft Academic Search

Ninety-two strains of lactic acid bacteria (LAB) were isolated from a Malaysian food ingredient, chili bo, stored for up to 25 days at 28C with no benzoic acid (product A) or with 7,000 mg of benzoic acid kg21 (product B). The strains were divided into eight groups by traditional phenotypic tests. A total of 43 strains were selected for comparison

JRGEN J. LEISNER; BRUNO POT; HENRIK CHRISTENSEN; GULAM RUSUL; JOHN E. OLSEN; BEE WAH WEE; KHARIDAH MUHAMAD; HASANAH M. GHAZALI

1999-01-01

367

Biotransformation of gallic acid by Beauveria sulfurescens ATCC 7159  

Microsoft Academic Search

Preparative-scale fermentation of gallic acid (3,4,5-trihydroxybenzoic acid) (1) with Beauveria sulfurescens ATCC 7159 gave two new glucosidated compounds, 4-(3,4-dihydroxy-6-hydroxymethyl-5-methoxy-tetrahydro-pyran-2-yloxy)-3-hydroxy-5-methoxy-benzoic\\u000a acid (4), 3-hydroxy-4,5-dimethoxy-benzoic acid 3,4-dihydroxy-6-hydroxymethyl-5-methoxy-tetrahydro-pyran-2-yl ester (7), along with four known compounds, 3-O-methylgallic acid (2), 4-O-methylgallic acid (3), 3,4-O-dimethylgallic acid (5), and 3,5-O-dimethylgallic acid (6). The new metabolite genistein 7-O-?-D-4?-O-methyl-glucopyranoside (8) was also obtained as a byproduct due to the use

Feng-Lin Hsu; Li-Ming Yang; Shwu-Fen Chang; Li-Hsuan Wang; Chung-Yi Hsu; Pan-Chun Liu; Shwu-Jiuan Lin

2007-01-01

368

Mefenamic Acid  

MedlinePLUS

... any of the following symptoms, stop taking mefenamic acid and call your doctor: stomach pain, heartburn, vomit that is bloody or looks ... Mefenamic acid may cause side effects. Tell your doctor if any of these ... nervousness ringing in the ears Some side effects can be serious. If you ...

369

Acid test  

NSDL National Science Digital Library

Baking soda can be used as an indicator of how much acid a substance contains. Lemons and limes have more acid in them than grapefruits and oranges. Indophenol can be used as an indicator of how much vitamin C is in a substance.

Olivia Worland (Purdue University;Biological Sciences)

2008-06-06

370

Acid Rain  

Microsoft Academic Search

Measurements of the acidity of rain and snow reveal that in parts of the eastern U.S. and of western Europe precipitation has changed from a nearly neutral solution 200 years ago to a dilute solution of sulfuric and nitric acids today. The trend is a result of the emission of sulfur and nitrogen oxides to the atmosphere accompanying the rise

Gene E. Likens; Richard F. Wright; James N. Galloway; Thomas J. Butler

1979-01-01

371

Acid rain  

SciTech Connect

This book was written in a concise and readable style for the lay public. It's purpose was to make the public aware of the damage caused by acid rain and to mobilize public opinion to favor the elimination of the causes of acid rain.

Elsworth, S.

1985-01-01

372

Acid rain  

SciTech Connect

This book presents the proceedings of the third annual conference sponsored by the Acid Rain Information Clearinghouse (ARIC). Topics covered include: Legal aspects of the source-receptor relationship: an energy perspective; Scientific uncertainty, agency inaction, and the courts; and Acid rain: the emerging legal framework.

White, J.C. (Cornell University, Ithaca, NY (US))

1988-01-01

373

Hydrochloric acid  

Microsoft Academic Search

The effect of a single instillation of acid and pepsin on the cell proliferation in the distal esophageal mucosa was investigated in four dogs. The doses of acid and pepsin used were lower than those provoking acute esophagitis and erosions. Usingin vitro labeling with [3H]thymidine and autoradiography, the epithelial mitotic and DNA synthesis indices were determined at 0, 4, 8,

A. De Backer; P. Haentjens; G. Willems

1985-01-01

374

Acids (GCMP)  

NSDL National Science Digital Library

Acids: this is a resource in the collection "General Chemistry Multimedia Problems". We will observe the reaction of sodium bicarbonate with three acid solutions. General Chemistry Multimedia Problems ask students questions about experiments they see presented using videos and images. The questions asked apply concepts from different parts of an introductory course, encouraging students to decompartmentalize the material.

375

Domoic Acid  

NSDL National Science Digital Library

This online student report discusses the chemistry of domoic acid, a biotoxin that is produced by the diatom Psuedo-nitzschia and associated with Amnesiac Shellfish Poisoning (ASP). In addition to a descriptive summary and images, the report links to other areas of interest related to domoic acid poisoning including signs and symptoms, modes of action, and treatment.

Kohlen, Corinne; Bailey, Christina

2010-02-10

376

Acid Precipitation  

NSDL National Science Digital Library

Acid precipitation will be defined. At different points in the lesson students will write balanced reactions for the formation acid precipitation from atmospheric sulfur and nitrogen oxides and the neutralization of acids by limestone. Students will determine which states are most at risk from acid precipitation and assess how that risk has changed from 1996 to 2006. Sources of atmospheric sulfur (burning of high-sulfur coal) and nitrogen oxides (automobile exhaust) will be listed. The buffering effect of limestone soils and its mitigating effect on acid precipitation will be discussed. Students will correlate these areas with sulfur and nitrogen oxide production, population, composition of coal fields, and soil composition. This resource includes both a teaching guide and student worksheets.

Tyser, Jim

2011-09-15

377

Acid rain  

SciTech Connect

Acid precipitation has become one of the major environmental problems of this decade. It is a challenge to scientists throughout the world. Researchers from such diverse disciplines as plant pathology, soil science, bacteriology, meteorology and engineering are investigating different aspects of acid precipitation. Despite some unknowns, the preponderance of our evidence to date points to the need to control the emissions of acid-forming sulfur and nitrogen compounds. Given the potential for damage from acid precipitation, prudence dictates that we act soon to avoid far more serious problems in the future. EPA's regulatory standards for new power plants and motor vehicles are a major step in the right direction. Further steps may be required in the near future. This background document tells what we know - and don't know - about acid precipitation.

Not Available

1980-07-01

378

Effect of benzoate on microbial decomposition of fulvic acids in Tjeukemeer ( the Netherlands )  

Microsoft Academic Search

Abstrud The addition of benzoic acid to water from Tjeukemeer stimulated bacterial growth and decreased both the fluorescence and the color of the water, indicating disappearance of fulvic acids. This stimulation of bacterial growth is shown to result most likely from a priming effect of bcnzoic acid on the slow microbial decomposition of fulvic acid. During growth of an Arthrobucter

H. DE HAAN

1977-01-01

379

Influence of vegetation on low-molecular-weight carboxylic acids in soil solutiona review  

Microsoft Academic Search

Low-molecular-weight (LMW) carboxylic acids found in soils and soil solutions comprise mainly aliphatic mono-, di- and tricarboxylic acids and substituted benzoic and cinnamic acids. This review compiles current information on the content of LMW carboxylic acids in soil solutions collected by centrifugation and in lysimeters, and soil extracts in relation to type of vegetation, soil type and soil depth. Contents

Bjarne W Strobel

2001-01-01

380

Microporous metal organic framework [M2(hfipbb)2(ted)] (M=Zn, Co; H2hfipbb=4,4-(hexafluoroisopropylidene)-bis(benzoic acid); ted=triethylenediamine): Synthesis, structure analysis, pore characterization, small gas adsorption and CO2/N2 separation properties  

NASA Astrophysics Data System (ADS)

Carbon dioxide is a greenhouse gas that is a major contributor to global warming. Developing methods that can effectively capture CO2 is the key to reduce its emission to the atmosphere. Recent research shows that microporous metal organic frameworks (MOFs) are emerging as a promising family of adsorbents that may be promising for use in adsorption based capture and separation of CO2 from power plant waste gases. In this work we report the synthesis, crystal structure analysis and pore characterization of two microporous MOF structures, [M2(hfipbb)2(ted)] (M=Zn (1), Co (2); H2hfipbb=4,4-(hexafluoroisopropylidene)-bis(benzoic acid); ted=triethylenediamine). The CO2 and N2 adsorption experiments and IAST calculations are carried out on [Zn2(hfipbb)2(ted)] under conditions that mimic post-combustion flue gas mixtures emitted from power plants. The results show that the framework interacts with CO2 strongly, giving rise to relatively high isosteric heats of adsorption (up to 28 kJ/mol), and high adsorption selectivity for CO2 over N2, making it promising for capturing and separating CO2 from CO2/N2 mixtures.

W. Xu, William; Pramanik, Sanhita; Zhang, Zhijuan; Emge, Thomas J.; Li, Jing

2013-04-01

381

Acid Rain  

NSDL National Science Digital Library

Due to the presence of dissolved gases such as carbon dioxide, rainfall is naturally acidic. The release of other gases and chemicals such as sulfur dioxide during the combustion of coal and oil can cause rainfall to become even more acidic, sometimes to the point of toxicity. In this activity, students will measure the pH of local rainfall to see what effect these gases have in their region. They will also check an online resource to see how the releases of acid rain-causing chemicals have varied over the past 20 years, and answer questions about the information they uncover.

Fox, Chris

382

Dissociative proton transfer in cluster ions: clusters of aromatic carboxylic acids with amino acids 1 1 Dedicated to Professor Nico Nibering on the occasion of his retirement  

Microsoft Academic Search

The cluster formation of several aromatic carboxylic acids ferulic acid, vanillic acid, sinapinic acid and 3,4-dihydroxy-benzoic acid was investigated by means of laser desorption into a supersonic beam followed by multiphoton ionization-time-of-flight mass spectrometry. The formation of not only homogeneous clusters but also that of heterogeneous clusters with some small amino acids was studied. The different neutral clusters formed in

Anja Meffert; Jrgen Grotemeyer

2001-01-01

383

Effects of microbial utilization of phenolic acids and their phenolic acid breakdown products on allelopathic interactions  

SciTech Connect

Reversible sorption of phenolic acids by soils may provide some protection to phenolic acids from microbial degradation. In the absence of microbes, reversible sorption 35 days after addition of 0.5--3 {micro}mol/g of ferulic acid or p-coumaric acid was 8--14% in Cecil A{sub p} horizon and 31--38% in Cecil B{sub t} horizon soil materials. The reversibly sorbed/solution ratios (r/s) for ferulic acid or p-coumaric acid ranged from 0.12 to 0.25 in A{sub p} and 0.65 to 0.85 in B{sub t} horizon soil materials. When microbes were introduced, the r/s ratio for both the A{sub p} and B{sub t} horizon soil materials increased over time up to 5 and 2, respectively, thereby indicating a more rapid utilization of solution phenolic acids over reversibly sorbed phenolic acids. The increase in r/s ratio and the overall microbial utilization of ferulic acid and/or p-coumaric acid were much more rapid in A{sub p} than in B{sub t} horizon soil materials. Reversible sorption, however, provided protection of phenolic acids from microbial utilization for only very short periods of time. Differential soil fixation, microbial production of benzoic acids (e.g., vanillic acid and p-hydroxybenzoic acid) from cinnamic acids (e.g., ferulic acid and p-coumaric acid, respectively), and the subsequent differential utilization of cinnamic and benzoic acids by soil microbes indicated that these processes can substantially influence the magnitude and duration of the phytotoxicity of individual phenolic acids.

Blum, U. [North Carolina State Univ., Raleigh, NC (United States). Dept. of Botany

1998-04-01

384

Tranexamic Acid  

MedlinePLUS

... or lower legs hoarseness changes in vision, including color vision chest pain shortness of breath leg pain, swelling, tenderness, redness, or warmth Tranexamic acid may cause other side effects. Call your doctor if you have any unusual ...

385

Valproic Acid  

MedlinePLUS

... with other medications to treat certain types of seizures. Valproic acid is also used to treat mania ( ... a severe, long-lasting and possibly life-threatening seizure. Your doctor will probably decrease your dose gradually.

386

Elucidation of the biochemical basis for a clinical drug-drug interaction between atorvastatin and 5-(N-(4-((4-ethylbenzyl)thio)phenyl)sulfamoyl)-2-methyl benzoic acid (CP-778?875), a subtype selective agonist of the peroxisome proliferator-activated receptor alpha.  

PubMed

Abstract 1.? 5-(N-(4-((4-ethylbenzyl)thio)phenyl)sulfamoyl)-2-methyl benzoic acid (CP-778?875), an agonist of the peroxisome proliferator-activated receptor alpha, has been evaluated in the clinic to treat dyslipidemia and type 2 diabetes mellitus. Herein, we investigate the effect of CP-778?875 on the pharmacokinetics of atorvastatin acid and its metabolites in humans. 2.? The study incorporated a fixed-sequence design conducted in two groups. Group A was designed to estimate the effects of multiple doses of CP-778?875 on the single dose pharmacokinetics of atorvastatin. Subjects in group A (n?=?26) received atorvastatin (40?mg) on days 1 and 9 and CP-778?875 (1.0?mg QD) on days 5-12. Group B was designed to examine the effects of multiple doses of atorvastatin on the single dose pharmacokinetics of CP-778?875. Subjects in group B (n?=?29) received CP-778?875 (0.3?mg) on days 1 and 9 and atorvastatin (40?mg QD) on days 5-12. 3.? Mean maximum serum concentration (Cmax) and area under the curve of atorvastatin were increased by 45% and 20%, respectively, upon co-administration with CP-778?875. Statistically significant increases in the systemic exposure of ortho- and para-hydroxyatorvastatin were also observed upon concomitant dosing with CP-778?875. CP-778?875 pharmacokinetics, however, were not impacted upon concomitant dosing with atorvastatin. 4.? Inhibition of organic anion transporting polypeptide 1B1 by CP-778?875 (IC50?=?2.14?0.40??M) could be the dominant cause of the pharmacokinetic interaction as CP-778?875 did not exhibit significant inhibition of cytochrome P450 3A4/3A5, multidrug resistant protein 1 or breast cancer resistant protein, which are also involved in the hepatobiliary disposition of atorvastatin. PMID:23631744

Kalgutkar, Amit S; Chen, Danny; Varma, Manthena V; Feng, Bo; Terra, Steven G; Scialis, Renato J; Rotter, Charles J; Frederick, Kosea S; West, Mark A; Goosen, Theunis C; Gosset, James R; Walsky, Robert L; Francone, Omar L

2013-04-30

387

?-Amino acids  

Microsoft Academic Search

Summary 1.It has been established that by the decarboxylation of the glycidic acid, obtained by Darzens' method from cis-decahydro-2-naphthol of m.p. 105, a mixture of stereoisomeric decahydro-2-naphthaldehydes is formed; these have not been investigated further.2.The synthesis has been affected, by Rodionov's method, of -(2-decalyl)--alanine (-aminodecahydro-2-naphthalenepropionic acid), which also appeared to be a mixture of isomers, the separation of which was

V. M. Rodionov; L. V. Antik

1953-01-01

388

Acidizing with chemically heated weak acid  

SciTech Connect

Materials in and around a well are acidized with chemically heated, hot acid by injecting a solution of both nitrogen and heat generating reactants and a mixture of weak acid and weak acid salt that both buffers the relation and provides a weak acid acidizing solution.

Richardson, E. A.

1984-11-13

389

Methanogenic Decomposition of Ferulic Acid, a Model Lignin Derivative  

PubMed Central

Ferulic acid, a model lignin derivative, was observed to be biodegradable to methane and carbon dioxide under strict anaerobic conditions. This conversion appears to be carried out by a consortium of bacteria similar to that previously described for the methanogenic degradation of benzoic acid. A temporary buildup of acetate in these cultures indicates that it is a likely intermediate and precursor for methane formation. An analog of coenzyme M, 2-bromoethanesulfonic acid (BESA), inhibited gas production and enhanced the buildup of propionate, butyrate, isobutyrate, and isovalerate. Phenylacetate, cinnamate, 3-phenylpropionate, benzoate, cyclohexane carboxylate, adipate, and pimelate were also detected in BESA-inhibited cultures. A pathway is proposed which includes these various acids as possible intermediates in the methanogenic degradation of ferulic acid. This model overlaps previously described benzoic acid degradation pathways, suggesting that this type of anaerobic degradation may be common for aromatic compounds. Images

Healy, J. B.; Young, L. Y.; Reinhard, M.

1980-01-01

390

Metabolite Profiles of Lactic Acid Bacteria in Grass Silage?  

PubMed Central

The metabolite production of lactic acid bacteria (LAB) on silage was investigated. The aim was to compare the production of antifungal metabolites in silage with the production in liquid cultures previously studied in our laboratory. The following metabolites were found to be present at elevated concentrations in silos inoculated with LAB strains: 3-hydroxydecanoic acid, 2-hydroxy-4-methylpentanoic acid, benzoic acid, catechol, hydrocinnamic acid, salicylic acid, 3-phenyllactic acid, 4-hydroxybenzoic acid, (trans, trans)-3,4-dihydroxycyclohexane-1-carboxylic acid, p-hydrocoumaric acid, vanillic acid, azelaic acid, hydroferulic acid, p-coumaric acid, hydrocaffeic acid, ferulic acid, and caffeic acid. Among these metabolites, the antifungal compounds 3-phenyllactic acid and 3-hydroxydecanoic acid were previously isolated in our laboratory from liquid cultures of the same LAB strains by bioassay-guided fractionation. It was concluded that other metabolites, e.g., p-hydrocoumaric acid, hydroferulic acid, and p-coumaric acid, were released from the grass by the added LAB strains. The antifungal activities of the identified metabolites in 100 mM lactic acid were investigated. The MICs against Pichia anomala, Penicillium roqueforti, and Aspergillus fumigatus were determined, and 3-hydroxydecanoic acid showed the lowest MIC (0.1 mg ml?1 for two of the three test organisms).

Broberg, Anders; Jacobsson, Karin; Strom, Katrin; Schnurer, Johan

2007-01-01

391

Stearic Acid  

ERIC Educational Resources Information Center

|A chemical laboratory information profile (CLIP) is presented for the chemical, stearic acid. The profile lists the chemical's physical and harmful characteristics, exposure limits, and symptoms of major exposure, for the benefit of teachers and students, who use the chemical in the laboratory.|

Young, Jay A.

2004-01-01

392

Acid rain  

SciTech Connect

An overview is presented of acid rain and the problems it causes to the environment worldwide. The acidification of lakes and streams is having a dramatic effect on aquatic life. Aluminum, present in virtually all forest soils, leaches out readily under acid conditions and interferes with the gills of all fish, some more seriously than others. There is evidence of major damage to forests in European countries. In the US, the most severe forest damage appears to be in New England, New York's Adirondacks, and the central Appalachians. This small region is part of a larger area of the Northeast and Canada that appears to have more acid rainfall than the rest of the country. It is downwind from major coal burning states, which produce about one quarter of US SO/sub 2/ emissions and one sixth of nitrogen oxide emissions. Uncertainties exist over the causes of forest damage and more research is needed before advocating expensive programs to reduce rain acidity. The President's current budget seeks an expansion of research funds from the current $30 million per year to $120 million.

Not Available

1984-06-01

393

Ethenzamide-gentisic acid-acetic acid (2/1/1)  

PubMed Central

In the title co-crystal solvate, 2-ethoxybenzamide2,5-dihydroxybenzoic acidethanoic acid (2/1/1), 2C9H11NO2C7H6O4C2H4O2, two nonsteroidal anti-inflammatory drugs, ethenzamide (systematic name: 2-ethoxybenzamide) and gentisic acid (systematic name: 2,5-dihydroxybenzoic acid), together with acetic acid (systematic name: ethanoic acid) form a four-component molecular assembly held together by NH?O and OH?O hydrogen bonds. This assembly features two symmetry-independent molecules of ethenzamide, forming supramolecular acidamide heterosynthons with gentisic acid and acetic acid. These heterosynthons involve quite strong OH?O [O?O = 2.5446?(15) and 2.5327?(15)?] and less strong NH?O [N?O = 2.9550?(17) and 2.9542?(17)?] hydrogen bonds. The overall crystal packing features several CH?O and ?? stacking interactions [centroidcentroid distance = 3.7792?(11)?].

Aitipamula, Srinivasulu; Chow, Pui Shan; Tan, Reginald B.H.

2010-01-01

394

Ethenzamide-gentisic acid-acetic acid (2/1/1).  

PubMed

In the title co-crystal solvate, 2-ethoxy-benzamide-2,5-dihydroxy-benzoic acid-ethanoic acid (2/1/1), 2C(9)H(11)NO(2)C(7)H(6)O(4)C(2)H(4)O(2), two nonsteroidal anti-inflammatory drugs, ethenzamide (systematic name: 2-ethoxy-benzamide) and gentisic acid (systematic name: 2,5-dihydroxy-benzoic acid), together with acetic acid (systematic name: ethanoic acid) form a four-component mol-ecular assembly held together by N-H?O and O-H?O hydrogen bonds. This assembly features two symmetry-independent mol-ecules of ethenzamide, forming supra-molecular acid-amide heterosynthons with gentisic acid and acetic acid. These heterosynthons involve quite strong O-H?O [O?O = 2.5446?(15) and 2.5327?(15)?] and less strong N-H?O [N?O = 2.9550?(17) and 2.9542?(17)?] hydrogen bonds. The overall crystal packing features several C-H?O and ?-? stacking inter-actions [centroid-centroid distance = 3.7792?(11)?]. PMID:21579106

Aitipamula, Srinivasulu; Chow, Pui Shan; Tan, Reginald B H

2010-04-10

395

Antimicrobial activity of phenolic acids against commensal, probiotic and pathogenic bacteria  

Microsoft Academic Search

Phenolic acids (benzoic, phenylacetic and phenylpropionic acids) are the most abundant phenolic structures found in fecal water. As an approach towards the exploration of their action in the gut, this paper reports the antimicrobial activity of thirteen phenolic acids towards Escherichia coli, Lactobacillus spp., Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans. The growth of E. coli ATCC 25922 was inhibited

Carolina Cueva; M. Victoria Moreno-Arribas; Pedro J. Martn-lvarez; Gerald Bills; M. Francisca Vicente; Angela Basilio; Concepcin Lpez Rivas; Teresa Requena; Juan M. Rodrguez; Begoa Bartolom

2010-01-01

396

The use of hydroxy acids on the skin: characteristics of C8-lipohydroxy acid.  

PubMed

The hydroxy acids are widely used in skin creams because of their exfoliating and rejuvenating effect on photoaged skin. As a member of this family, the salicylic acid derivative known in the literature as 2-hydroxy-5-octanoyl benzoic acid or beta-lipohydroxy acid has also been proposed as an exfoliant and as a treatment of photoaged skin and acne. This article reviews the effects of the hydroxy acids and compares them to those of the salicylic acid derivative. We propose the name C(8)-lipohydroxy acid (C8-LHA) for this derivative to differentiate it from other related compounds. The lipophilic nature of C8-LHA and its relatively slow penetration in the skin afford it an exfoliating effect that is efficient at low concentrations. It appears to have antimicrobial, anti-inflammatory, and anticomedogenic properties, which make it effective against acne. Its antifungal and exfoliating properties are also likely to prove useful in combating dandruff. PMID:17348998

Saint-Lger, Didier; Lvque, Jean-Luc; Verschoore, Michle

2007-03-01

397

Carbonate acidizing  

SciTech Connect

The authors present the first quantitative study and complete model of the wormholing phenomenon, leading to a means of predicting and optimizing carbonate acidizing treatments. Laboratory experiments on a gypsum model system and computer simulations show that for a given geometry, wormholes can be quantified by a unique parameter, their equivalent hydraulic length. The behavior of this quantifying parameter vs. all the system parameters is studied and allows the quantitative prediction of the efficiency of an acidizing treatment. This study highlights the fractal nature of the phenomenon, which is accounted for in the equations, and the strong effect of the sample geometry. Three types of etching can be obtained: compact, wormhole type, or homogeneous. The optimum conditions for achieving the best skin decrease correspond to the creation of wormholes and can then be defined in terms of fluid reactivity and injection rate.

Daccord, G.; Touboul, E.; Lenormand, R.

1989-02-01

398

Biodegradability enhancement of purified terephthalic acid wastewater by coagulationflocculation process as pretreatment  

Microsoft Academic Search

In this work, the coagulationflocculation process was used as pretreatment for purified terephthalic acid (PTA) wastewater with the objective of improving its overall biodegradability. PTA production generates wastewaters with toxicants p-xylene [1,4-dimethyl-benzene (C8H10)], a major raw material used in the production process, along with some of the intermediates, viz., p-toluic acid, benzoic acid, 4-carboxybenzaldehyde, phthalic acid and terephthalic acid. These

Manikavasagam Karthik; Nishant Dafale; Pradyumna Pathe; Tapas Nandy

2008-01-01

399

Participation of phenolic acids of microbial origin in the dysfunction of mitochondria in sepsis  

Microsoft Academic Search

The role of low-molecular-weight phenolic acids of microbial origin in the mitochondrial dysfunction observed in sepsis has\\u000a been studied. It was shown that microbial phenolic acids formed during fermentation of aromatic amino acids and polyphenols\\u000a have an effect on mitochondrial functions, whose magnitude depends on the structure of a particular phenolic acid. The anaerobic\\u000a metabolites cinnamic and benzoic acids and,

N. I. Fedotcheva; V. V. Teplova; N. V. Beloborodova

2010-01-01

400

Contributions of Drug Solubilization, Partitioning, Barrier Disruption, and Solvent Permeation to the Enhancement of Skin Permeation of Various Compounds with Fatty Acids and Amines  

Microsoft Academic Search

The contributions of several proposed mechanisms by which fatty acids and amines might increase skin permeation rates were assessed. Permeation rates of model diffusants with diverse physicochemical properties (naloxone, testosterone, benzoic acid, indomethacin, fluorouracil, and methotrexate) through human skin were measured in vitro. The enhancers evaluated were capric acid, lauric acid, neodecanoic acid, and dodecylamine. Increased drug solubility in the

Bruce J. Aungst; Judy A. Blake; Munir A. Hussain

1990-01-01

401

Acidizing sandstone formations with fluoboric acid  

SciTech Connect

The continuing search for an effective deep-penetrating sandstone acidizing system recently has focused on fluoboric acid (HBF/sub 4/). Because this acid first must hydrolyze in water to produce HF, it was believed that deeper radial penetration of live acid could be achieved during matrix acidizing operations. However, a thorough experimental study has shown that typical formation temperatures will cause fluoboric acid to spend at a rapid rate similar to that of conventional hydrofluoric acid (HF), thereby severly limiting its usefulness in most sandstone formations. Furthermore, the same silica reprecipitation potential associated with HF acidizing is also inherent in the HBF/sub 4/ system.

Kunze, K.R.; Shaughnessy, C.M.

1983-02-01

402

Uptake of phenoxyacetic acid derivatives into Caco-2 cells by the monocarboxylic acid transporters.  

PubMed

The uptake mechanism of phenoxyacetic acid (PA) and its chlorine derivatives, 4-chlorophenoxyacetic acid (4-CPA), 2,4-dichlorophenoxyacetic acid (2,4-D), and 2,4,5-trichlorophenoxyacetic acid (2,4,5-T), was investigated using Caco-2 cells. The cells were incubated with PA, 4-CPA, 2,4-D or 2,4,5-T at pH 6.0 and 37 degrees C. The order of uptake and lipophilicity expressed by n-octanol partition coefficients were PA<4-CPA<2,4-D<2,4,5-T. Incubation at 4 degrees C or at pH 7.4 significantly decreased these uptake. Furthermore, pretreatment with the protonophore, carbonylcyanide-p-(trifluoromethoxy) phenylhydrazone, or coincubation with benzoic acid, a typical substrate for the proton-linked monocarboxylic acid transporters (MCTs), significantly decreased the uptake of all compounds. The initial uptake rates of all compounds except PA were apparently saturable, suggesting the involvement of a carrier-mediated process. The order of uptake clearance of the compounds was the same as the order of their uptake and lipophilicity. Preloading of cells with benzoic acid significantly increased their uptake except for PA. These results suggest that the uptake of PA, 4-CPA, 2,4-D and 2,4,5-T from the apical membrane of Caco-2 cells is mediated via common MCTs shared, at least in part, with benzoic acid, and the increase in lipophilicity due to the chlor-substitution may increase uptake via the MCTs. PMID:19465094

Kimura, Osamu; Tsukagoshi, Kensuke; Endo, Tetsuya

2009-05-22

403

Understanding Acid Rain  

ERIC Educational Resources Information Center

|The term acid rain describes rain, snow, or fog that is more acidic than normal precipitation. To understand what acid rain is, it is first necessary to know what an acid is. Acids can be defined as substances that produce hydrogen ions (H+), when dissolved in water. Scientists indicate how acidic a substance is by a set of numbers called the pH

Damonte, Kathleen

2004-01-01

404

Acidizing concepts - Matrix vs. fracture acidizing  

SciTech Connect

Acidizing involves a wide range of stimulation treatments that can yield impressive production increases in many wells if properly applied. Acidizing treatments are divided into two categories: matrix acidizing and fracture acidizing. To use either treatment properly, an understanding is required of what the treatments do and what is necessary to stimulate the well.

King, G.E.

1986-05-01

405

FT-IR and NMR spectroscopic studies of salicylic acid derivatives. II. Comparison of 2-hydroxy- and 2,4- and 2,5-dihydroxy derivatives.  

PubMed

The 2,4- and 2,5-dihydroxybenzamides (8, 9) were synthesized from their corresponding methyl esters. The structures and the spectral properties of investigated salicylic acid (1), 2,4- and 2,5-dihydroxy benzoic acids (2, 3), their methyl esters (4-6) and amides (7-9) were analyzed by means of FT-IR and one- and two-dimensional homo- and heteronuclear 1H and 13C NMR spectroscopies. Comparison of FT-IR and NMR spectral data of investigated compounds showed that the spectral characteristics of 2,4-dihydroxy benzoic acid derivatives are more similar to those of 2-hydroxy benzoic acid (salicylic acid) derivatives than to those of 2,5-dihydroxy benzoic acid derivatives. The results suggest that the spatial orientation of amide protons in 2,4-dihydroxy benzamide resembles more that in salicylamide than that in 2,5-dihydroxy benzamide. PMID:15610615

Jadrijevi?-Mladar Takac, Milena; Viki? Topi?, Drazen

2004-09-01

406

(E)-4-(4-Fluoro-styr-yl)benzoic acid  

PubMed Central

The title compound, C15H11FO2, is an important intermediate in the synthesis of side-chain ligands for polymeric liquid crystals. The vinyl group is almost coplanar with both the aromatic rings. The crystal structure is stabilized by intermolecular OH?O hydrogen bonding.

Nazir, Saba; Muhammad, Khushi; Khawar Rauf, M.; Ebihara, Masahiro; Hameed, Shahid

2008-01-01

407

4-[(E)-(4-Fluoro-benzyl-idene)amino]-benzoic acid  

PubMed Central

In the title compound, C14H10FNO2, the benzene rings make a dihedral angle of 57.50?(13), and the molecule has an E configuration about the C=N bond. In the crystal, molecules are linked via pairs of OH?O hydrogen bonds, forming inversion dimers.

Munoz-Flores, Blanca M.; Perez, Victor M. Jimenez; Santillan, Rosa L.; Ochoa, Maria Eugenia; Waksman, Noemi

2012-01-01

408

Benzoic acid glucosinolate esters and other glucosinolates from Arabidopsis thaliana.  

PubMed

The spectacular recent progress in Arabidopsis thaliana molecular genetics furnishes outstanding tools for studying the formation and function of all metabolites in this cruciferous species. One of the major groups of secondary metabolites in A. thaliana is the glucosinolates. These hydrophilic, sulfur-rich glycosides appear to serve as defenses against some generalist herbivores and pathogens, and as feeding and oviposition stimulants to specialist herbivores. To help study their biosynthesis and role in plant-insect interactions, we wanted to determine the complete glucosinolate content of A. thaliana. In previous studies, 24 glucosinolates had been identified from ecotype Columbia. We reinvestigated Columbia as well as additional ecotypes and mutant lines, and identified 12 further glucosinolates, including five novel compounds. Structures were elucidated by MS and NMR spectroscopy of their desulfated derivatives, and by enzymatic cleavage of the attached ester moieties. Four of the novel glucosinolates are benzoate esters isolated from the seeds. In all but one of these compounds, esterification is on the glucose moiety rather than the side chain, a very unusual feature for glucosinolates. Among additional glucosinolates identified were the first non-chain elongated, methionine-derived glucosinolate from A. thaliana and the first compounds that appear to be derived from leucine. PMID:11867099

Reichelt, Michael; Brown, Paul D; Schneider, Bernd; Oldham, Neil J; Stauber, Einar; Tokuhisa, Jim; Kliebenstein, Daniel J; Mitchell-Olds, Thomas; Gershenzon, Jonathan

2002-03-01

409

2-Fluoro-4-(meth-oxy-carbon-yl)benzoic acid  

PubMed Central

In the crystal of the title compound, C9H7FO4, classical carboxylate inversion dimers are linked by pairs of OH?O hydrogen bonds. The packing is consolidated by CH?F and CH?O interactions. The benzene ring and the methoxycarbonyl group are nearly coplanar, with a dihedral angle of 1.5?(3) between them, whereas the carboxyl group has a dihedral angle of 20.2?(4) with respect to the benzene ring.

Wagner, Carl E.; Groy, Thomas L.

2010-01-01

410

HEALTH AND ENVIRONMENTAL EFFECTS DOCUMENT FOR BENZOIC ACID  

EPA Science Inventory

Health and Environmental Effects Documents (HEEDS) are prepared for the Office of Solid Waste and Emergency Response (OSWER). his document series is intended to support listings under the Resource Conservation and Recovery Act (RCRA) as well as to provide health-related limits an...

411

Benzoic acid glucosinolate esters and other glucosinolates from Arabidopsis thaliana  

Microsoft Academic Search

The spectacular recent progress in Arabidopsis thaliana molecular genetics furnishes outstanding tools for studying the formation and function of all metabolites in this cruciferous species. One of the major groups of secondary metabolites in A. thaliana is the glucosinolates. These hydrophilic, sulfur-rich glycosides appear to serve as defenses against some generalist herbivores and pathogens, and as feeding and oviposition stimulants

Michael Reichelt; Paul D Brown; Bernd Schneider; Neil J Oldham; Einar Stauber; Jim Tokuhisa; Daniel J Kliebenstein; Thomas Mitchell-Olds; Jonathan Gershenzon

2002-01-01

412

Uptake of triclopyr (3,5,6-trichloro-2-pyridinyloxyacetic acid) and dicamba (3,6-dichloro-2-methoxybenzoic acid) from the apical membranes of the human intestinal Caco-2 cells.  

PubMed

We investigated whether the uptake of triclopyr (3, 5, 6-trichloro-2-pyridinyloxyacetic acid) and dicamba (3,6-dichloro-2-methoxybenzoic acid) across the apical membrane of Caco-2 cells was mediated via proton-linked monocarboxylic acid transporters (MCTs). The uptake of triclopyr from the apical membranes was fast, pH-, temperature-, and concentration dependent, required metabolic energy to proceed, and was competitively inhibited by monocarboxylic acids such as benzoic acid and ferulic acid (substrates of L-lactic acid-insensitive MCTs), but not by L-lactic acid. Thus, the uptake of triclopyr in Caco-2 cells appears to be mediated mainly via L-lactic acid-insensitive MCTs. In contrast, the uptake of dicamba (a benzoic acid derivative) was slow, and it was both pH- and temperature dependent. Coincubation with ferulic acid did not decrease the uptake of dicamba, although coincubation with benzoic acid moderately decreased it. The uptake of dicamba appears to be mediated mainly via passive diffusion, which is in contrast to the uptake of benzoic acid via MCTs. We speculate that the substituted groups in dicamba may inhibit uptake via MCTs. PMID:21766207

Kimura, Osamu; Tsukagoshi, Kensuke; Hayasaka, Moriaki; Endo, Tetsuya

2011-07-16

413

New method of acidizing or acid fracturing: crosslinked acid gels  

SciTech Connect

Acid polymer gels having pH less than one have been crosslinked for retarding the chemical and physical activity of hydrochloric acid on calcareous formations. Hydrochloric acid concentrations from .0025 to 28% have been successfully crosslinked. This stimulation fluid offers high viscosity with adequate shear stability, perfect support for proppants, and clay stabilization. Additionally, the fluid provides effective fluid loss control and retardation of acid reaction enabling live acid to penetrate deeper into the formation for better formation conductivity and practically a residue-free break for rapid clean-up of the well after the job. Results of lab and field tests show the acid crosslinked system to be an effective stimulation fluid for acidizing and acid fracturing in calcareous and sandstone formations having low formation permeability.

Pabley, A.S.; Holcomb, D.L.

1980-01-01

414

Isolation and Characterization of Thermophilic Bacilli Degrading Cinnamic, 4-Coumaric, and Ferulic Acids  

PubMed Central

Thirty-four thermophilic Bacillus sp. strains were isolated from decayed wood bark and a hot spring water sample based on their ability to degrade vanillic acid under thermophilic conditions. It was found that these bacteria were able to degrade a wide range of aromatic acids such as cinnamic, 4-coumaric, 3-phenylpropionic, 3-(p-hydroxyphenyl)propionic, ferulic, benzoic, and 4-hydroxybenzoic acids. The metabolic pathways for the degradation of these aromatic acids at 60C were examined by using one of the isolates, strain B1. Benzoic and 4-hydroxybenzoic acids were detected as breakdown products from cinnamic and 4-coumaric acids, respectively. The ?-oxidative mechanism was proposed to be responsible for these conversions. The degradation of benzoic and 4-hydroxybenzoic acids was determined to proceed through catechol and gentisic acid, respectively, for their ring fission. It is likely that a non-?-oxidative mechanism is the case in the ferulic acid catabolism, which involved 4-hydroxy-3-methoxyphenyl-?-hydroxypropionic acid, vanillin, and vanillic acid as the intermediates. Other strains examined, which are V0, D1, E1, G2, ZI3, and H4, were found to have the same pathways as those of strain B1, except that strains V0, D1, and H4 had the ability to transform 3-hydroxybenzoic acid to gentisic acid, which strain B1 could not do.

Peng, Xue; Misawa, Norihiko; Harayama, Shigeaki

2003-01-01

415

Acid rain  

SciTech Connect

Deposition of acidic substances from the atmosphere is considered by many to be, along with increasing CO/sub 2/ concentrations in the atmosphere, one of the most serious environmental problems of this generation. Despite the limited title of this small book, it touches, in a nontechnical and elementary way, on all of the important aspects of this subject: definitions, history, suspected causes and harmful effects, proposed remedial actions, the case for additional research, and political and economic impacts. The material is presented largely as statements and opinions of scientists and governmental officials. The book is reportorial in style and reasonably balanced in its presentation of contrasting and opposing opinions about causes, effects, and remedies, although the final chapter, What Citizens Can Do, includes the names and addresses of organizations involved in efforts to protect clean air, forestry and wilderness areas. Also included are school projects and examples of what individuals and groups have done to help us understand the problem and/or to promote action.

Gay, K.

1983-01-01

416

Nano sulfated titania as solid acid catalyst in direct synthesis of fatty acid amides.  

PubMed

Nanosized sulfated titania was prepared by a sol-gel hydrothermal process. X-ray diffraction (XRD), transmission electron, and scanning electron micrographs (TEM and SEM), FT-IR specific surface area, and BET N(2) adsorption were employed to characterize the properties of the synthesized sulfated TiO(2). The results indicate that both anatase and rutile TiO(2) are obtainable. This prepared sulfated titania showed high catalytic activity in direct amidation of fatty acids as well as benzoic acids with various amines under solvent-free conditions. PMID:21405011

Hosseini-Sarvari, Mona; Sodagar, Esmat; Doroodmand, Mohammad Mahdi

2011-03-23

417

On the inhibition of muscle membrane chloride conductance by aromatic carboxylic acids  

Microsoft Academic Search

A B S T R A C T 25 aromatic carboxylic acids which are analogs of benzoic acid were tested in the rat diaphragm preparation for effects on chloride conductance (Gc~). Of the 25, 19 were shown to reduce membrane Gca with little effect on other membrane parameters, although their apparent Kl varied widely. This inhibition was reversible if exposure

P. T. PALADE; R. L. BARCHI

1977-01-01

418

An NMR relaxation study on the proton transfer in the hydrogen bonded carboxylic acid dimers  

Microsoft Academic Search

We have studied the proton spin-lattice relaxation times (T1) of a series of benzoic acid (BAC) derivatives and decanoic acid (DAC) over a wide range of temperature and analyzed the results in terms of the double proton switching along the hydrogen bonds. The proton T1 in the high temperature region are analyzed using the classical jump model and the barrier

S. Nagaoka; T. Terao; F. Imashiro; A. Saika; N. Hirota; S. Hayashi

1983-01-01

419

COMBINING ORGANIC ACID TREATMENT WITH STEAM PASTEURIZATION TO ELIMINATE LISTERIA MONOCYTOGENES ON FULLY-COOKED FRANKFURTERS  

Technology Transfer Automated Retrieval System (TEKTRAN)

In this study, an organic acid solution, including acetic (2%), lactic (1%), propionic (0.1%), and benzoic acid (0.1%), were combined with steam surface pasteurization to treat frankfurters during vacuum packaging to eliminate potentially post-cook contaminated L. monocytogenes. The thermal lethali...

420

Uric acid test (image)  

MedlinePLUS

Uric acid urine test is performed to check for the amount of uric acid in urine. Urine is collected over a 24 ... testing. The most common reason for measuring uric acid levels is in the diagnosis or treatment of ...

421

Aqueous iodic acid: conductance and thermodynamics  

SciTech Connect

Precision conductance measurements are reported on aqueous solutions of iodic acid for 16 concentrations between 17 and 0.7 mM and for 20 temperatures between 5/sup 0/ and 100/sup 0/C. RlnK/sub a/(m) and ..lambda../sub 0/ were calculated at each temperature and the data expressed by suitable temperature functions. From RlnK/sub a/(m) as a function of temperature changes in standard enthalpy, entropy, and heat capacity were calculated. ..delta..C/sub p/ proved to be independent of temperature so that ..delta..H/sup 0/ was a linear function of temperature. Comparisons have been made with other published data for iodic acid. The pattern of variation of Walden products with temperature was similar to that found earlier for substituted benzoic acids.

Strong, L.E.; Pethybridge, A.D.

1987-10-01

422

A novel ortho-dehalogenation reaction of 2-chlorocinnamic acid catalyzed by the pink yeast Rhodotorula rubra Y-1529  

Microsoft Academic Search

In the present study, a resting cells suspension of Rhodotorula rubra Y-1529 was shown to have the capacity to perform an ortho-dehalogenation reaction on 2-chlorocinnamic acid. The results from the biodegradation of U-[14C]benzoic acid, cinnamic acid, 3-chlorocinnamic acid and 4-chlorocinnamic acid suggest that the first step of the ortho-dehalogenation reaction occurred during the oxidation of the unsaturated C3 side chain

Fang-Ming Sun; Juie S Wang; Richard W Traxler

2000-01-01

423

Use of water and EDTA extractions to estimate available (free and reversibly bound) phenolic acids in Cecil soils  

Microsoft Academic Search

Sterile and microbe reinfested Cecil Ap and Bt soil materials amended with 0 to 5 mol\\/g of ferulic acid,p-coumaric acid,p-hydroxybenzoic acid, or vanillic acid were extracted after varying time intervals with water, EDTA, or NaOH to characterize sorption of cinnamic and benzoic acid derivatives and to determine the effectiveness of water and EDTA extractions in estimating concentrations of free and

U. Blum; A. D. Worsham; L. D. King; T. M. Gerig

1994-01-01

424

An oxazine reagent for derivatization of carboxylic acid analytes suitable for liquid chromatographic detection using visible diode laser-induced fluorescence.  

PubMed

This study reports the use of Nile Blue, an oxazine dye, as a derivatization reagent that fluoresces in the far-red spectral region and is suitable for derivatization with carboxylic-acid-containing analytes. Model carboxylic acid analytes such as benzoic acid, acetic acid, phenylacetic acid and hexanoic acid have been reacted as acid chlorides to form Nile Blue derivatives. The synthesis product of the Nile Blue benzoic acid derivative was confirmed using electrospray-mass spectrometry, infrared spectrometry, 1H and 13C nuclear magnetic resonance, reversed phase liquid chromatography (RP-HPLC), normal phase-thin layer chromatography, and spectral characterization. The synthesized Nile Blue derivatives, separated from reaction by-products with RP-HPLC, all demonstrated an approximately 10-fold drop in molar absorptivity and relative quantum yield. In addition, a 40 nm increase in Stokes shift was observed. A portion of the fluorescence was regained through post-column ionization of the Nile Blue benzoic acid derivative at pH 12. A RP-HPLC limit of detection of 88.25 fmol on column has been reported with conventional fluorescence detection-post-column ionization of the Nile Blue benzoic acid derivative. A limit of detection of 1.99 fmol on column (3.98 x 10(-11) M) has been demonstrated for the Nile Blue benzoic acid derivative with the use of a laboratory-constructed visible diode laser fluorescence detector. PMID:8895079

Rahavendran, S V; Karnes, H T

1996-10-01

425

BBB - Domoic Acid Structure  

Center for Food Safety and Applied Nutrition (CFSAN)

... BBB - Domoic Acid Structure. Bad Bug Book: Foodborne Pathogenic Microorganisms and Natural Toxins Handbook Domoic Acid. ... More results from www.fda.gov/food/foodborneillnesscontaminants/causesofillnessbadbugbook

426

BBB - Okadaic Acid Structure  

Center for Food Safety and Applied Nutrition (CFSAN)

... BBB - Okadaic Acid Structure. Bad Bug Book: Foodborne Pathogenic Microorganisms and Natural Toxins Handbook Okadaic Acid. ... More results from www.fda.gov/food/foodborneillnesscontaminants/causesofillnessbadbugbook

427

Communication: The ionization spectroscopy of mixed carboxylic acid dimers  

NASA Astrophysics Data System (ADS)

We report mass analyzed threshold ionization spectroscopy of supersonically cooled gas phase carboxylic complexes with 9-hydroxy-9-fluorenecarboxylic acid (9HFCA), an analog of glycolic acid. The vibrationally resolved cation spectrum for the 9HFCA complex with formic acid allows accurate determination of its ionization potential (IP), 64 374 +/- 8 cm-1. This is 545 cm-1 smaller than the IP of 9HFCA monomer. The IPs of 9HFCA complexes with acetic acid and benzoic acid shift by -1133 cm-1 and -1438 cm-1, respectively. Density functional calculations confirm that Cs symmetry is maintained upon ionization of the 9HFCA monomer and its acid complexes, in contrast to the drastic geometric rearrangement attending ionization in complexes of 9-fluorene carboxylic acid. We suggest that the marginal geometry changes and small IP shifts are primarily due to the collective interactions among one intramolecular and two intermolecular hydrogen bonds in the dimer.

Yang, Zhijun; Gu, Quanli; Trindle, Carl O.; Knee, J. L.

2013-10-01

428

Communication: The ionization spectroscopy of mixed carboxylic acid dimers.  

PubMed

We report mass analyzed threshold ionization spectroscopy of supersonically cooled gas phase carboxylic complexes with 9-hydroxy-9-fluorenecarboxylic acid (9HFCA), an analog of glycolic acid. The vibrationally resolved cation spectrum for the 9HFCA complex with formic acid allows accurate determination of its ionization potential (IP), 64?374 8 cm(-1). This is 545 cm(-1) smaller than the IP of 9HFCA monomer. The IPs of 9HFCA complexes with acetic acid and benzoic acid shift by -1133 cm(-1) and -1438 cm(-1), respectively. Density functional calculations confirm that Cs symmetry is maintained upon ionization of the 9HFCA monomer and its acid complexes, in contrast to the drastic geometric rearrangement attending ionization in complexes of 9-fluorene carboxylic acid. We suggest that the marginal geometry changes and small IP shifts are primarily due to the collective interactions among one intramolecular and two intermolecular hydrogen bonds in the dimer. PMID:24160490

Yang, Zhijun; Gu, Quanli; Trindle, Carl O; Knee, J L

2013-10-21

429

Growth and membrane fluidity of food-borne pathogen Listeria monocytogenes in the presence of weak acid preservatives and hydrochloric acid  

PubMed Central

This study addresses a major issue in microbial food safety, the elucidation of correlations between acid stress and changes in membrane fluidity of the pathogen Listeria monocytogenes. In order to assess the possible role that membrane fluidity changes play in L. monocytogenes tolerance to antimicrobial acids (acetic, lactic, hydrochloric acid at low pH or benzoic acid at neutral pH), the growth of the bacterium and the gel-to-liquid crystalline transition temperature point (Tm) of cellular lipids of each adapted culture was measured and compared with unexposed cells. The Tm of extracted lipids was measured by differential scanning calorimetry. A trend of increasing Tm values but not of equal extent was observed upon acid tolerance for all samples and this increase is not directly proportional to each acid antibacterial action. The smallest increase in Tm value was observed in the presence of lactic acid, which presented the highest antibacterial action. In the presence of acids with high antibacterial action such as acetic, hydrochloric acid or low antibacterial action such as benzoic acid, increased Tm values were measured. The Tm changes of lipids were also correlated with our previous data about fatty acid changes to acid adaptation. The results imply that the fatty acid changes are not the sole adaptation mechanism for decreased membrane fluidity (increased Tm). Therefore, this study indicates the importance of conducting an in-depth structural study on how acids commonly used in food systems affect the composition of individual cellular membrane lipid molecules.

Diakogiannis, Ioannis; Berberi, Anita; Siapi, Eleni; Arkoudi-Vafea, Angeliki; Giannopoulou, Lydia; Mastronicolis, Sofia K.

2013-01-01

430

Uptake of 4-chloro-2-methylphenoxyacetic acid (MCPA) from the apical membrane of Caco-2 cells by the monocarboxylic acid transporter  

SciTech Connect

The cellular uptake mechanism of 4-chloro-2-methylphenoxyacetic acid (MCPA), a phenoxyacetic acid derivative, was investigated using Caco-2 epithelial cells. The cells were incubated with 50 {mu}M MCPA at pH 6.0 and 37 deg. C, and the uptake of MCPA from the apical membranes was measured. The uptake of MCPA was significantly decreased by incubation at low temperature (4 {sup o}C) and markedly increased by lowering the extracellular pH. Pretreatment with a protonophore, carbonylcyanide-p-(trifluoromethoxy)phenylhydrazone (25 {mu}M), or metabolic inhibitors, 2,4-dinitrophenol (1 mM) and sodium azide (10 mM), significantly decreased the uptake of MCPA by 53%, 45% and 48%, respectively. Coincubation of MCPA with 10 mM L-lactic acid or {alpha}-cyano-4-hydroxycinnamate, which is a substrate or an inhibitor of the monocarboxylic acid transporters (MCTs), significantly decreased the uptake of MCPA by 31% and 20%, respectively, and coincubation with benzoic acid profoundly decreased the uptake by 68%. In contrast, coincubation with succinic acid (a dicarboxylic acid) did not affect the uptake. Kinetic analysis of initial MCPA uptake suggested that MCPA is taken up via a carrier-mediated process [K{sub m} = 1.37 {+-} 0.15 mM, V{sub max} = 115 {+-} 6 nmol (mg protein){sup -1} (3 min){sup -1}]. Lineweaver-Burk plots show that benzoic acid competitively inhibits the uptake of MCPA with a K{sub i} value of 4.68 {+-} 1.76 mM. A trans-stimulation effect on MCPA uptake was found in cells preloaded with benzoic acid. These results suggest that the uptake of MCPA from the apical membrane of Caco-2 cells is mainly mediated by common MCTs along with benzoic acid but also in part by L-lactic acid.

Kimura, Osamu; Tsukagoshi, Kensuke [Faculty of Pharmaceutical Sciences, Health Sciences University of Hokkaido, 1757 Ishikari-Tobetsu, Hokkaido 061-0293 (Japan); Endo, Tetsuya [Faculty of Pharmaceutical Sciences, Health Sciences University of Hokkaido, 1757 Ishikari-Tobetsu, Hokkaido 061-0293 (Japan)], E-mail: endotty@hoku-iryo-u.ac.jp

2008-03-15

431

Simultaneous gas chromatographic determination of carboxylic acids in soft drinks and jams.  

PubMed

A method was developed for simultaneous gas chromatographic determination of sorbic acid, dehydroacetic acid, and benzoic acid used as preservatives, and succinic acid, fumaric acid, malic acid, and tartaric acid used as acidulants in soft drinks and jams. A sample was dissolved in NH4OH-NH4Cl pH 9 buffer solution, and an aliquot of the solution was passed through a QAE-Sephadex A 25 column. The column was washed with water, and the carboxylic acids were eluted with 0.1N HCl. Sorbic acid, dehydroacetic acid, and benzoic acid were extracted with ethyl ether-petroleum ether (1 + 1), and determined on a 5% DEGS + 1% H3PO4 column. Succinic acid, fumaric acid, malic acid, and tartaric acid in the lower layer were derivatized with N,O-bis(trimethylsilyl)acetamide and trimethylchlorosilane, and determined on a 3% SE-30 column. Recoveries from soft drink and jam samples fortified with 0.1% each of 7 carboxylic acids ranged from 92.4 to 102.6% for preservatives, and from 88.1 to 103.2% for acidulants. PMID:4055637

Tsuda, T; Nakanishi, H; Morita, T; Takebayashi, J

432

Direct preparation of nitriles from carboxylic acids in continuous flow.  

PubMed

A continuous-flow protocol for the preparation of organic nitriles from carboxylic acids has been developed. The method is based on the acid-nitrile exchange reaction with acetonitrile, used as the solvent, and takes place without any catalyst or additives under the high-temperature/high-pressure conditions employed. At 350 C and 65 bar, where acetonitrile is in its supercritical state, the transformation of benzoic acid to benzonitrile requires 25 min. The protocol has been tested for a variety of nitriles, including aromatic and aliphatic substrates. PMID:24066706

Cantillo, David; Kappe, C Oliver

2013-10-08

433

Refining Lurgi tar acids  

Microsoft Academic Search

There is disclosed a process for removing tar bases and neutral oils from the Lurgi tar acids by treating the tar acids with aqueous sodium bisulfate to change the tar bases to salts and to hydrolyze the neutral oils to hydrolysis products and distilling the tar acids to obtain refined tar acid as the distillate while the tar base salts

Greco

1984-01-01

434

Acid-Base Equilibria  

NSDL National Science Digital Library

This 9-page PDF document is part of an environmental geochemistry course taught by Dr. David Sherman at the University of Bristol. Topics include acid-base theories, aqueous systems, strong and weak acids and bases, acid-base properties of minerals, the pH of weak acid and buffered systems, and the calculation of titration curves.

Sherman, David W.; Bristol, University O.

435

21 CFR 172.860 - Fatty acids.  

Code of Federal Regulations, 2013 CFR

...acids and their associated fatty acids manufactured from fats and oils derived from edible sources: Capric acid, caprylic acid, lauric acid, myristic acid, oleic acid, palmitic acid, and stearic acid. (b) The food additive meets the...

2013-04-01

436

21 CFR 172.860 - Fatty acids.  

Code of Federal Regulations, 2010 CFR

...acids and their associated fatty acids manufactured from fats and oils derived from edible sources: Capric acid, caprylic acid, lauric acid, myristic acid, oleic acid, palmitic acid, and stearic acid. (b) The food additive meets the...

2009-04-01

437

21 CFR 172.860 - Fatty acids.  

Code of Federal Regulations, 2010 CFR

...acids and their associated fatty acids manufactured from fats and oils derived from edible sources: Capric acid, caprylic acid, lauric acid, myristic acid, oleic acid, palmitic acid, and stearic acid. (b) The food additive meets the...

2010-01-01

438

Uric acid nephrolithiasis.  

PubMed

Uric acid nephrolithiasis may be the final manifestation of various pathophysiological processes. Recent advances in renal urate transport have elucidated mechanisms by which hyperuricosuria occurs. However, in most uric acid stone formers the primary pathophysiologic defect is an excessively acidic urine pH rather than hyperuricosuria. Insulin resistance may contribute to the development of acidic urine by augmenting endogenous acid production and decreasing renal ammonium excretion. Medical management strategies focus primarily on alkali treatment or decreasing hyperuricosuria. PMID:17678984

Cameron, Mary Ann; Sakhaee, Khashayar

2007-08-01

439

Acids and Bases (Netorials)  

NSDL National Science Digital Library

Acids and Bases: this is a resource in the collection "Netorials". In this module there is an introduction to the chemical properties of acids and bases. Afterwards, the sections include topics such as Molecular Structures of Acids and Bases, Ionization constants, properties of salts, buffers and Lewis theory of Acids and Bases. The Netorials cover selected topics in first-year chemistry including: Chemical Reactions, Stoichiometry, Thermodynamics, Intermolecular Forces, Acids & Bases, Biomolecules, and Electrochemistry.

440

Investigation of the thermal decomposition of sulfuric acid containing inorganic impurities  

SciTech Connect

Oleum is recovered by thermal decomposition of sulfuric acid wastes to sulfur dioxide with conversion of the sulfur dioxide to oleum. The organic substances in sulfuric acid wastes can affect the thermal-decomposition indexes of sulfuric acid wastes. They studied the effect of toluene, nitrotoluene, benzoic acid, and carbon on the yield of sulfur dioxide and also the possibility of reduction of acid vapors by products of pyrolysis and incomplete combustion of hydrocarbons. It is shown that the yield of sulfur dioxide in thermal decomposition of hydrocarbon-containing sulfuric acid wastes can be increased if the process assumes the nature of reductive decomposition.

Kogtev, S.E.; Nikandrov, I.S.; Borisenko, A.S.; Peretrutov, A.A.

1986-09-20

441

Detection of bound phenolic acids: prevention by ascorbic acid and ethylenediaminetetraacetic acid of degradation of phenolic acids during alkaline hydrolysis  

Microsoft Academic Search

The experimental conditions commonly used to detect bound phenolic acids by alkaline hydrolysis result in loss of several phenolic acids, particularly dihydroxy-derivatives (caffeic acid, dihydrocaffeic acid, homogentisic acid). In this study we show that the addition of ascorbic acid, a strong antioxidant, and ethylenediaminetetraacetic acid, a metal chelator, totally prevent the loss of phenolic acids during alkaline hydrolysis. In these

M Nardini; E Cirillo; F Natella; D Mencarelli; A Comisso; C Scaccini

2002-01-01

442

Inhibition of polygalacturonase and polygalacturonic acid lyase from Erwinia carotovora subsp. carotovora by phenolics in vitro  

Microsoft Academic Search

SummaryThe phenolic acids benzoic, caffeic, chlorogenic, ferulic, p-coumaric, protocatechuic, salicylic, sinapic, syringic and vanillic\\u000a together with vanillin, were tested for their ability to inhibit polygalacturonic acid lyase (PL) and polygalacturonase (PG)\\u000a in culture filtrates ofErwinia carotovora subsp.carotovora. None of the compounds inhibited PL at 200 ?g\\/ml, although syringic and sinapic acids caused a 54% and 43% reduction respectively\\u000a at 400

G. D. Lyon; Fiona M. McGill

1989-01-01

443

Gas-phase Acidities of Aspartic Acid, Glutamic Acid, and their Amino Acid Amides.  

SciTech Connect

Gas-phase acidities (GA or ?Gacid) for the two most acidic common amino acids, aspartic acid and glutamic acid, have been determined for the first time. Because of the amide linkages importance in peptides and as an aid in studying side chain versus main chain deprotonation, aspartic acid amide and glutamic acid amide were also studied. Experimental GA values were measured by proton transfer reactions in an electrospray ionization/Fourier transform ion cyclotron resonance mass spectrometer. Calculated GAs were obtained by density functional and molecular orbital theory approaches. The best agreement with experiment was found at the G3MP2 level; the MP2/CBS and B3LYP/aug-cc-pVDZ results are 34 kcal/mol more acidic than the G3MP2 results. Experiment shows that aspartic acid is more acidic than glutamic acid by ca. 3 kcal/mol whereas the G3MP2 results show a smaller acidity difference of 0.2 kcal/mol. Similarly, aspartic acid amide is experimentally observed to be ca. 2 kcal/mol more acidic than glutamic acid amide whereas the G3MP2 results show a correspondingly smaller energy difference of 0.7 kcal/mol. The computational results clearly show that the anions are all ring-like structures with strong hydrogen bonds between the OH or NH2 groups and the CO2? group from which the proton is removed. The two amino acids are main-chain deprotonated. In addition, use of the COSMO model for the prediction of the free energy differences in aqueous solution gave values in excellent agreement with the most recent experimental values for pKa. Glutamic acid is predicted to be more acidic than aspartic acid in aqueous solution due to differential solvation effects.

Li, Zhong; Matus, Myrna H.; Velazquez, Hector A.; Dixon, David A.; Cassady, Carolyn J.

2007-02-14

444

Separation of aromatic carboxylic acids using quaternary ammonium salts on reversed-phase HPLC. 1. Separation behavior of aromatic carboxylic acids  

SciTech Connect

In order to develop separation processes and analytical methods for aromatic carboxylic acids for the coal oxidation products, the separation behavior of aromatic carboxylic acids on a reversed-phase HPLC using eluent containing quaternary ammonium salt has been investigated. The retention mechanism of aromatic carboxylic acids was discussed on the basis of both ion-pair partition model and ion-exchange model. The retention behavior of aromatic carboxylic acids possessing one (or two) carboxylic acid group(s) followed the ion-pair partition model, where linear free energy relationship was observed between the capacity factor and the extraction equilibrium constants of benzoic acid and naphthalene carboxylic acid. Besides, the retention behavior followed ion-exchange model with increasing the number of carboxylic acids, where the capacity factor of benzene polycarboxylic acids is proportional to the association constants between aromatic acids and quaternary ammonium ions calculated on the basis of an electrostatic interaction model.

Kawamura, K.; Okuwaki, A.; Verheyen, T.; Perry, G.J. [Tohoku University, Miyagi (Japan). Graduate School of Environmental Studies

2006-02-15

445

Acid Inhibition and the Acid Rebound Effect  

Microsoft Academic Search

Acid secretion from gastric parietal cells is a result of a complex interaction between different stimulatory and inhibitory mediators. One of the most important mediators is gastrin, which stimulates gastric acid secretion from parietal cells mostly indirectly, by the release of histamine from enterochromaffin-like (ECL) cells. Therapy with antisecretory agents leads to hypergastrinemia, mucosal hyperplasia and increased ECL cell mass,

Marko Duvnjak

2011-01-01

446

Acid Thunder: Acid Rain and Ancient Mesoamerica  

ERIC Educational Resources Information Center

|Much of Mesoamerica's rich cultural heritage is slowly eroding because of acid rain. Just as water dissolves an Alka-Seltzer tablet, acid rain erodes the limestone surfaces of Mexican archaeological sites at a rate of about one-half millimeter per century (Bravo et al. 2003). A half-millimeter may not seem like much, but at this pace, a few

Kahl, Jonathan D. W.; Berg, Craig A.

2006-01-01

447

Purification of oleic acid and linoleic acid  

SciTech Connect

To permit kinetic studies of the reactivity of unsaturated fatty acids towards oxygen radicals, it is essential to remove traces of hydroperoxides and other conjugated lipid impurities commonly present in commercial samples. Removal of these impurities has been satisfactorily achieved for oleic and linoleic acids by anaerobic low temperature recrystallization from acetonitrile. The uv spectra of commercial and purified samples are compared.

Arudi, R.L.; Sutherland, M.W.; Bielski, B.H.J.

1983-01-01

448

New bioactive fatty acids.  

PubMed

Many oxygenated fatty acids are bioactive compounds. Nocardia cholesterolicum and Flavobacterium DS5 convert oleic acid to 10 hydroxy stearic acid and linoleic acid to 10-hydroxy-12(Z)-octadecanoic acid. Pseudomonas aeruginosa PR3 converts oleic acid to the new compounds, 7,10-dihydroxy-8(E)-octadecenoic acid (DOD) through 10-hydroxy-8-octadecenoic acid, and racinoleic acid to 7,10,12-trihydroxy-8-octadecenoic acid. DOD showed antibacterial activity including against food-borne pathogens. Bacillus megaterium ALA2 converted n-6 and n-3 PUFAs to many new oxygenated fatty acids. For example: linoleic acid was converted to12,13-epoxy-9-octadecenoic acid and then to 12,13-dihydroxy-9-octadecenoic acid (12,13-DHOA). From here, there are two bioconversion pathways. The major pathway is: 12,13-DHOA --> 12,13,17-trihydroxy-9(S)-octadecenoic acid (THOA) --> 12,17;13,17-diepoxy-16-hydroxy-9(Z)-octadecenoic acid (DEOA) --> 7-hydroxy-DEOA. The minor pathway is: 12,13-DHOA --> 12,13,16-THOA --> 12-hydroxy-13,16-epoxy-9(Z)-octadecenoic acid. 12,13,17-THOA has anti-plant pathogenic fungal activity. The tetrahydrofuranyl moiety is known in anti cancer drugs. Strain ALA2 also converts other n-3 and n-6 PUFAs such as eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA) and arachidonic acid (AA) to many new oxygenated unsaturated fatty acid products. All of these new products have high potential for antimicrobial agents or biomedical applications. We also screened 12 Mortierella fungal strains from the ARS Culture Collection for the production of bioactive fatty acids such as dihomo-gama-linolenic acid (DGLA) and arachidonic acid. All of the strains tested produced AA and DGLA from glucose or glycerol. The top five AA producers (mg AA/g CDW) were in the following order: M. alpina > M. zychae > M. hygrophila > M. minutissima > M. parvispora. Both AA and DGLA are important natural precursors of a large family of prostaglandin and thromboxane groups. PMID:18296335

Hou, Ching T

2008-01-01

449

Effect of anions on the efficiency of aromatic carboxylic acid corrosion inhibitors in near neutral media: Experimental investigation and theoretical modeling  

Microsoft Academic Search

The influence of the nature and concentration of electrolyte anions on the efficiency of carboxylic acid based inhibitors for steel in neutral solution was studied using anodic and cathodic polarization at a rotating disk electrode. The N-ethyl-morpholine salts of a ?-benzoyl alcanoic acid model compound and of benzoic acid were used as inhibitors. Both compounds were found to inhibit the

P. Agarwal; D. Landolt

1998-01-01

450

40 CFR 704.33 - P-tert-butylbenzoic acid (P-TBBA), p-tert-butyltoluene (P-TBT) and p-tert-butylbenzaldehyde (P-TBB).  

Code of Federal Regulations, 2010 CFR

...P-tert-butylbenzoic acid (P-TBBA), p-tert-butyltoluene...p-tert-butylbenzoic acid, also identified as 4-(1,1-dimethylethyl)benzoic acid, CAS No. 98-73-7... (3) Persons who process P-TBBA, P-TBT,...

2010-07-01

451

40 CFR 704.33 - P-tert-butylbenzoic acid (P-TBBA), p-tert-butyltoluene (P-TBT) and p-tert-butylbenzaldehyde (P-TBB).  

Code of Federal Regulations, 2010 CFR

...P-tert-butylbenzoic acid (P-TBBA), p-tert-butyltoluene...p-tert-butylbenzoic acid, also identified as 4-(1,1-dimethylethyl)benzoic acid, CAS No. 98-73-7... (3) Persons who process P-TBBA, P-TBT,...

2009-07-01

452

Zoledronic Acid Injection  

MedlinePLUS

... acid (Reclast) is used to prevent or treat osteoporosis (condition in which the bones become thin and ... Zoledronic acid (Reclast) is also used to treat osteoporosis in men, and to prevent or treat osteoporosis ...

453

Mixed Acid Oxidation  

SciTech Connect

Several non-thermal processes have been developed to destroy organic waste compounds using chemicals with high oxidation potentials. These efforts have focused on developing technologies that work at low temperatures, relative to incineration, to overcome many of the regulatory issues associated with obtaining permits for waste incinerators. One such technique with great flexibility is mixed acid oxidation. Mixed acid oxidation, developed at the Savannah River Site, uses a mixture of an oxidant (nitric acid) and a carrier acid (phosphoric acid). The carrier acid acts as a non-volatile holding medium for the somewhat volatile oxidant. The combination of acids allows appreciable amounts of the concentrated oxidant to remain in the carrier acid well above the oxidant''s normal boiling point.

Pierce, R.A.

1999-10-26

454

Hydrochloric acid poisoning  

MedlinePLUS

Hydrocholoric acid is a clear, poisonous liquid. It is highly corrosive, which means it immediately causes severe damage, such ... poisoning due to swallowing or breathing in hydrochloric acid. This is for information only and not for ...

455

Acid-fast stain  

MedlinePLUS

The acid-fast stain is a laboratory test that determines if a sample of tissue, blood, or other body ... lab team member washes the slide with an acid solution and applies a different stain. The bacteria ...

456

Carbolic acid poisoning  

MedlinePLUS

Phenol poisoning; Phenylic acid poisoning; Hydroxybenzene poisoning; Phenic acid poisoning; Benzenol poisoning ... Phenol ... and Disease Registry (ATSDR). 2008. Toxicological profile for Phenol. Atlanta, GA: U.S. Department of Health and Human ...

457

Lactic acid test  

MedlinePLUS

Lactate test ... test. Exercise can cause a temporary increase in lactic acid levels. ... oxygen. See: Oxygen deprivation Conditions that can increase lactic acid levels include: Heart failure Liver problems Lung disease ...

458

Aminocaproic Acid Injection  

MedlinePLUS

Aminocaproic acid injection is used to control bleeding that occurs when blood clots are broken down too quickly. This ... the baby is ready to be born). Aminocaproic acid injection is also used to control bleeding in ...

459

Polymerization of Itaconic Acid.  

National Technical Information Service (NTIS)

Itaconic acid has various uses in chain copolymerization reactions, because of its two carboxylic groups and relatively good reactivity with different comonomers. As an unsaturated dicarboxylic acid it also has applications in grafting reactions and polyc...

J. Ahlgren

1990-01-01

460

Novel S-adenosyl- l-methionine:salicylic acid carboxyl methyltransferase, an enzyme responsible for biosynthesis of methyl salicylate and methyl benzoate, is not involved in floral scent production in snapdragon flowers  

Microsoft Academic Search

Using a functional genomic approach we have isolated and characterized a cDNA that encodes a salicylic acid carboxyl methyltransferase (SAMT) from Antirrhinum majus. The sequence of the protein encoded by SAMT has higher amino acid identity to Clarkia breweri SAMT than to snapdragon benzoic acid carboxyl methyltransferase (BAMT) (55 and 40% amino acid identity, respectively). Escherichia coli-expressed SAMT protein catalyzes

Florence Negre; Natalia Kolosova; Joseph Knoll; Christine M Kish; Natalia Dudareva

2002-01-01

461

Acid inhibition and the acid rebound effect.  

PubMed

Acid secretion from gastric parietal cells is a result of a complex interaction between different stimulatory and inhibitory mediators. One of the most important mediators is gastrin, which stimulates gastric acid secretion from parietal cells mostly indirectly, by the release of histamine from enterochromaffin-like (ECL) cells. Therapy with antisecretory agents leads to hypergastrinemia, mucosal hyperplasia and increased ECL cell mass, which results in increase of gastric acid secretion capacity. This increased secretion capacity has been shown to manifest itself after antisecretory therapy withdrawal as rebound acid hypersecretion (RAH). Various studies have quantified acid hypersecretion after the cessation of therapy with H(2) antagonists and proton-pump inhibitors (PPIs). While most of those studies had small patient numbers, the findings generally demonstrate that RAH after H(2) antagonist therapy is of low magnitude, short duration, and has questionable clinical significance. On the contrary, acid hypersecretion after PPI therapy is more pronounced, lasts longer, and could possibly be the cause of acid-related symptoms. Potential for causing symptoms has recen