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1

21 CFR 584.200 - Ethyl alcohol containing ethyl acetate.  

...2014-04-01 2014-04-01 false Ethyl alcohol containing ethyl acetate. 584.200...Affirmed as GRAS § 584.200 Ethyl alcohol containing ethyl acetate. The feed additive ethyl alcohol containing ethyl acetate meets the...

2014-04-01

2

Molecular Structure of Ethyl acetate  

NSDL National Science Digital Library

Ethyl acetate is a colorless, volatile liquid with a mild and fragrant odor. It is used as solvent in chemistry laboratories but can also be found in many household products such as paints, coatings, and adhesives. The compound is also used in some extraction processes such as decaffeination or purification of antibiotics. It is present in both nail polish and removers. Some synthetic fruit essences may contain this and other esters. Etymologists like to use this solvent for insect collecting as the vapor kill the insect quickly and keep it soft for mounting.

2006-03-08

3

Manufacturing Ethyl Acetate From Fermentation Ethanol  

NASA Technical Reports Server (NTRS)

Conceptual process uses dilute product of fermentation instead of concentrated ethanol. Low-concentration ethanol, extracted by vacuum from fermentation tank, and acetic acid constitutes feedstock for catalytic reaction. Product of reaction goes through steps that increases ethyl acetate content to 93 percent by weight. To conserve energy, heat exchangers recycle waste heat to preheat process streams at various points.

Rohatgi, Naresh K.; Ingham, John D.

1991-01-01

4

Health and environmental effects profile for ethyl acetate  

SciTech Connect

The Health and Environmental Effects Profile for ethyl acetate was prepared to support listings of hazardous constituents of a wide range of waste streams under Section 3001 of the Resource Conservation and Recovery Act (RCRA) and to provide health-related limits for emergency actions under Section 101 of the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA). Both published literature and information obtained from Agency program office files were evaluated as they pertained to potential human-health, aquatic-life and environmental effects of hazardous-waste constituents. Ethyl acetate has been determined to be a systemic toxicant. The daily exposure to the human population (including sensitive subgroups) that is likely to be without appreciable risk of deleterious effect during a lifetime, for ethyl acetate is 0.9 mg/kg/day for oral exposure. The Reportable Quantity (RQ) value for ethyl acetate is 1000.

Not Available

1986-12-01

5

DISCOVERY OF METHYL ACETATE AND GAUCHE ETHYL FORMATE IN ORION  

SciTech Connect

We report on the discovery of methyl acetate, CH{sub 3}COOCH{sub 3}, through the detection of a large number of rotational lines from each one of the spin states of the molecule: AA species (A{sub 1} or A{sub 2}), EA species (E{sub 1}), AE species (E{sub 2}), and EE species (E{sub 3} or E{sub 4}). We also report, for the first time in space, the detection of the gauche conformer of ethyl formate, CH{sub 3}CH{sub 2}OCOH, in the same source. The trans conformer is also detected for the first time outside the Galactic center source SgrB2. From the derived velocity of the emission of methyl acetate, we conclude that it arises mainly from the compact ridge region with a total column density of (4.2 {+-} 0.5) Multiplication-Sign 10{sup 15} cm{sup -2}. The derived rotational temperature is 150 K. The column density for each conformer of ethyl formate, trans and gauche, is (4.5 {+-} 1.0) Multiplication-Sign 10{sup 14} cm{sup -2}. Their abundance ratio indicates a kinetic temperature of 135 K for the emitting gas and suggests that gas-phase reactions could participate efficiently in the formation of both conformers in addition to cold ice mantle reactions on the surface of dust grains.

Tercero, B.; Cernicharo, J.; Lopez, A.; Caro, G. M. Munoz [Department of Astrophysics, CAB, INTA-CSIC, Crta Torrejon-Ajalvir, km. 4, E-28850 Torrejon de Ardoz, Madrid (Spain); Kleiner, I.; Nguyen, H. V. L., E-mail: terceromb@cab.inta-csic.es, E-mail: jcernicharo@cab.inta-csic.es, E-mail: lopezja@cab.inta-csic.es, E-mail: munozcg@cab.inta-csic.es, E-mail: isabelle.kleiner@lisa.u-pec.fr, E-mail: nguyen@pc.rwth-aachen.de [Laboratoire Interuniversitaire des Systemes Atmospheriques, CNRS/IPSL UMR7583 et Universites Paris Diderot et Paris Est, 61 av. General de Gaulle, F-94010 Creteil (France)

2013-06-10

6

Discovery of Methyl Acetate and Gauche Ethyl Formate in Orion  

NASA Astrophysics Data System (ADS)

We report on the discovery of methyl acetate, CH3COOCH3, through the detection of a large number of rotational lines from each one of the spin states of the molecule: AA species (A1 or A2), EA species (E1), AE species (E2), and EE species (E3 or E4). We also report, for the first time in space, the detection of the gauche conformer of ethyl formate, CH3CH2OCOH, in the same source. The trans conformer is also detected for the first time outside the Galactic center source SgrB2. From the derived velocity of the emission of methyl acetate, we conclude that it arises mainly from the compact ridge region with a total column density of (4.2 ± 0.5) × 1015 cm-2. The derived rotational temperature is 150 K. The column density for each conformer of ethyl formate, trans and gauche, is (4.5 ± 1.0) × 1014 cm-2. Their abundance ratio indicates a kinetic temperature of 135 K for the emitting gas and suggests that gas-phase reactions could participate efficiently in the formation of both conformers in addition to cold ice mantle reactions on the surface of dust grains. This work was based on observations carried out with the IRAM 30 m telescope. IRAM is supported by INSU/CNRS (France), MPG (Germany), and IGN (Spain).

Tercero, B.; Kleiner, I.; Cernicharo, J.; Nguyen, H. V. L.; López, A.; Muñoz Caro, G. M.

2013-06-01

7

Nitrosation of glycine ethyl ester and ethyl diazoacetate to give the alkylating agent and mutagen ethyl chloro(hydroximino)acetate.  

PubMed

Whereas nitrosation of secondary amines produces nitrosamines, amino acids with primary amino groups and glycine ethyl ester were reported to react with nitrite to give unidentified agents that alkylated 4-(p-nitrobenzyl)pyridine to produce purple dyes and be direct mutagens in the Ames test. We report here that treatment of glycine ethyl ester at 37 degrees C with excess nitrite acidified with HCl, followed by ether extraction, gave 30-40% yields of a product identified as ethyl chloro(hydroximino)acetate [ClC(=NOH)COOEt, ECHA] and a 9% yield of ethyl chloroacetate. The ECHA was identical to that synthesized by a known method from ethyl acetoacetate, strongly alkylated nitrobenzylpyridine, and may have arisen by N-nitrosation of glycine ethyl ester to give ethyl diazoacetate, which was C-nitrosated and reacted with chloride to give ECHA. Nitrosation of ethyl diazoacetate also yielded ECHA. Ethyl nitroacetate was not an intermediate as its nitrosation did not produce ECHA. ECHA reacted with aniline to give ethyl (hydroxamino)(phenylimino)acetate [PhN=C(NHOH)CO2Et]. This product was different from ethyl [(phenylamino)carbonyl]carbamate [PhNHC(=O)NHCO2Et], which was synthesized by reacting ethyl isocyanatoformate (OCN.CO2Et) with aniline. ECHA reacted with guanosine to give a derivative, which may have been a guanine-C(=NOH)CO2Et derivative. ECHA showed moderate toxicity and weak but significant mutagenicity without activation in Salmonella typhimurium TA-100 (mean, 1.31 x control value for 12-18 microg/plats) and for V79 mammalian cells (1.5-1.7 x control value for 60-100 microM). In conclusion, gastric nitrosation of glycine derivatives such as peptides with a N-terminal glycine might produce ECHA analogues that alkylate bases of gastric mucosal DNA and thereby initiate gastric cancer. PMID:15025513

Zhou, Lin; Haorah, James; Chen, Sheng C; Wang, Xiaojie; Kolar, Carol; Lawson, Terence A; Mirvish, Sidney S

2004-03-01

8

Antihyperglycemic effect of Hypericum perforatum ethyl acetate extract on streptozotocin-induced diabetic rats  

PubMed Central

Objective To evaluate the antihyperglycemic activity of ethyl acetate extract of Hypericum perforatum (H. perforatum) in streptozotocin (STZ)-induced diabetic rats. Methods Acute toxicity and oral glucose tolerance test were performed in normal rats. Male albino rats were rendered diabetic by STZ (40 mg/kg, intraperitoneally). H. perforatum ethyl acetate extract was orally administered to diabetic rats at 50, 100 and 200 mg/kg doses for 15 days to determine the antihyperglycemic activity. Biochemical parameters were determined at the end of the treatment. Results H. perforatum ethyl acetate extract showed dose dependant fall in fasting blood glucose (FBG). After 30 min of extract administration, FBG was reduced significantly when compared with normal rats. H. perforatum ethyl acetate extract produced significant reduction in plasma glucose level, serum total cholesterol, triglycerides, glucose-6-phosphatase levels. Tissue glycogen content, HDL-cholesterol, glucose-6-phosphate dehydrogenase were significantly increased compared with diabetic control. No death or lethal effect was observed in the toxic study. Conclusions The results demonstrate that H. perforatum ethyl acetate extract possesses potent antihyperglycemic activity in STZ induced diabetic rats. PMID:23569798

Arokiyaraj, S; Balamurugan, R; Augustian, P

2011-01-01

9

Effect of Potent Ethyl Acetate Fraction of Stereospermum suaveolens Extract in Streptozotocin-Induced Diabetic Rats  

PubMed Central

To evaluate the antihyperglycemic effect of ethyl acetate fraction of ethanol extract of Stereospermum suaveolens in streptozotocin-(STZ-) induced diabetic rats by acute and subacute models. In this paper, various fractions of ethanol extract of Stereospermum suaveolens were prepared and their effects on blood glucose levels in STZ-induced diabetic rats were studied after a single oral administration (200?mg/kg). Administration of the ethyl acetate fraction at 200?mg/kg once daily for 14 days to STZ-induced diabetic rats was also carried out. The parameters such as the fasting blood glucose, hepatic glycogen content, and pancreatic antioxidant levels were monitored. In the acute study, the ethyl acetate fraction is the most potent in reducing the fasting serum glucose levels of the STZ-induced diabetic rats. The 14-day repeated oral administration of the ethyl acetate fraction significantly reduced the fasting blood glucose and pancreatic TBARS level and significantly increased the liver glycogen, pancreatic superoxide dismutase, and catalase activities as well as reduced glutathione levels. The histopathological studies during the subacute treatment have been shown to ameliorate the STZ-induced histological damage of pancreas. This paper concludes that the ethyl acetate fraction from ethanol extract of Stereospermum suaveolens possesses potent antihyperglycemic and antioxidant properties, thereby substantiating the use of plant in the indigenous system of medicine. PMID:22593683

Balasubramanian, T.; Chatterjee, Tapan Kumar; Senthilkumar, G. P.; Mani, Tamizh

2012-01-01

10

Performance of a composite membrane bioreactor for the removal of ethyl acetate from waste air.  

PubMed

Ethyl acetate removal from an air stream was carried out by using a flat composite membrane bioreactor. The composite membrane consisted of a dense polydimethylsiloxane top layer with an average thickness of 0.3 ?m supported in a porous polyacrylonitrile layer (50 ?m). The membrane bioreactor (MBR) was operated during 3 months, and a maximum elimination capacity of 225 g m?³ h?¹ at an empty bed residence time of 60s was observed. Removal efficiencies higher than 95% were obtained for inlet loads lower than 200 g m?³ h?¹ and empty bed residence times as short as 15 s. The estimated yield coefficient, determined from the carbon dioxide production, resulted in 0.82 g dry biomass synthesized per gram of ethyl acetate degraded. No data of ethyl acetate treatment in MBR have been found in the literature, but the results illustrate that membrane bioreactors can potentially be a good option for its treatment. PMID:21763129

Álvarez-Hornos, F J; Volckaert, D; Heynderickx, P M; Van Langenhove, H

2011-10-01

11

Characterization and antioxidant properties of six Algerian propolis extracts: ethyl acetate extracts inhibit myeloperoxidase activity.  

PubMed

Because propolis contains many types of antioxidant compounds such as polyphenols and flavonoids, it can be useful in preventing oxidative damages. Ethyl acetate extracts of propolis from several Algerian regions show high activity by scavenging free radicals, preventing lipid peroxidation and inhibiting myeloperoxidase (MPO). By fractioning and assaying ethyl acetate extracts, it was observed that both polyphenols and flavonoids contribute to these activities. A correlation was observed between the polyphenol content and the MPO inhibition. However, it seems that kaempferol, a flavonoid, contributes mainly to the MPO inhibition. This molecule is in a high amount in the ethyl acetate extract and demonstrates the best efficiency towards the enzyme with an inhibiting concentration at 50% of 4 ± 2 µM. PMID:24514562

Boufadi, Yasmina Mokhtaria; Soubhye, Jalal; Riazi, Ali; Rousseau, Alexandre; Vanhaeverbeek, Michel; Nève, Jean; Boudjeltia, Karim Zouaoui; Van Antwerpen, Pierre

2014-01-01

12

On using film boiling to thermally decompose liquid organic chemicals: Application to ethyl acetate as a model compound  

E-print Network

On using film boiling to thermally decompose liquid organic chemicals: Application to ethyl acetate 21 August 2013 Keywords: Film boiling Thermal decomposition Pyrolysis Ethyl acetate Critical heat flux (CHF) Leidenfrost point a b s t r a c t Film boiling on a horizontal tube is used to study

Walter, M.Todd

13

Selective determination of ethyl acetate, acetone, ethanol, and methyl ethyl ketone using quartz crystal nanobalance combined with principle component analysis.  

PubMed

Quartz crystal nanobalance (QCN) sensors are considered as powerful mass sensitive sensors to determine materials in the subnanogram level. In the current study a method based on QCN modified with polyethylene glycol (PEG) has been developed to determine organic vapors (ethyl acetate, acetone, ethanol and methyl ethyl ketone). The frequency shift of QCN was found to be linear against analytes concentrations in the range between 4 to 35 mg/L for acetone vapor and 4-70 mg/L for 3 other vapors. The correlation coefficients for ethyl acetate, acetone, ethanol, and methyl ethyl ketone were 0.9971, 0.9976, 0.9984 and 0.9927, respectively. The principal component analysis was also utilized to process the frequency response data of the organic vapors. Using principal component analysis, it was found that over 95% of the data variance could still be explained by use of two principal components (PC1 and PC2). Subsequently, the successful discrimination of ethyl acetate and other compounds was possible through the principal component analysis of the transient responses of the PEG-modified QCN sensor. PMID:19799053

Mirmohseni, A; Razzaghi, M A; Pourata, R; Rastgouye-Hojagan, M; Zavareh, S

2009-07-15

14

(R)-1-Phenyl-ethyl-ammonium trifluoro-acetate.  

PubMed

In the crystal structure of the title salt, C(8)H(12)N(+)·C(2)F(3)O(2) (-), all of the ammonium H atoms serve as donors for hydrogen bonds to carboxyl-ate O atoms, forming an R(4) (3)(10) ring motif based on two cations and two anions. Since both cations and anions act as inter-ion bridging groups, R(10) rings aggregate in a one-dimensional supra-molecular network by sharing the strongest N-H?O bond. Edge-sharing motifs lie on the twofold screw axis parallel to [010], and anti-parallel packing of these 2(1)-column structural units results in the crystal structure. This arrangement is one of the most commonly occurring in conglomerates of chiral 1-phenyl-ethyl-amine with achiral monocarboxylic acids, confirming that these ionic salts are particularly robust supra-molecular heterosynthons useful in crystal engineering. PMID:21579169

Hernández Linares, María-Guadalupe; Guerrero Luna, Gabriel; Bernès, Sylvain

2010-01-01

15

Mixture Toxicity of SN2-Reactive Soft Electrophiles: 2--Evaluation of Mixtures Containing Ethyl ?-Halogenated Acetates  

PubMed Central

Four ethyl ?-halogenated acetates were tested in (1) sham and (2) nonsham combinations and (3) with a nonreactive nonpolar narcotic. Ethyl iodoacetate (EIAC), ethyl bromoacetate (EBAC), ethyl chloroacetate (ECAC), and ethyl fluoroacetate (EFAC), each considered to be an SN2-H-polar soft electrophile, were selected for testing based on their differences in electro(nucleo)philic reactivity and time-dependent toxicity (TDT). Agent reactivity was assessed using the model nucleophile glutathione, with EIAC and EBAC showing rapid reactivity, ECAC being less reactive, and EFAC lacking reactivity at ?250 mM. The model nonpolar narcotic, 3-methyl-2-butanone (3M2B), was not reactive. Toxicity of the agents alone and in mixture was assessed using the Microtox acute toxicity test at three exposure durations: 15, 30 and 45 min. Two of the agents alone (EIAC and EBAC) had TDT values >100%. In contrast, ECAC (74 to 99%) and EFAC (9 to 12%) had partial TDT, whereas 3M2B completely lacked TDT (<0%). In mixture testing, sham combinations of each agent showed a combined effect consistent with predicted effects for dose-addition at each time point, as judged by EC50 dose-addition quotient values. Mixture toxicity results for nonsham ethyl acetate combinations were variable, with some mixtures being inconsistent with the predicted effects for dose-addition and/or independence. The ethyl acetate–3M2B combinations were somewhat more toxic than predicted for dose-addition, a finding differing from that observed previously for ?-halogenated acetonitriles with 3M2B. PMID:21452006

Mooneyham, T.; Jeyaratnam, J.; Schultz, T. W.; Poch, G.

2011-01-01

16

Alternanthera sessilis Red Ethyl Acetate Fraction Exhibits Antidiabetic Potential on Obese Type 2 Diabetic Rats.  

PubMed

The antidiabetic potential of Alternanthera sessilis Red was investigated using the obese type 2 diabetic rats induced by high fat diet and streptozotocin. Three fractions (hexane, ethyl acetate, and water) were obtained from the crude ethanol extract of Alternanthera sessilis Red. Alternanthera sessilis Red ethyl acetate fraction (ASEAF) was found to possess the most potent antihyperglycemic effect through oral glucose tolerance test. The ASEAF was subsequently given to the diabetic rats for two weeks. It was found that two-week administration of ASEAF reduces the fasting blood glucose level, triglyceride level, and free fatty acid level of the rats. ASEAF-treated diabetic rats showed higher pancreatic insulin content and pancreatic total superoxide dismutase activity compared to the untreated diabetic rats. Also, the insulin sensitivity indexes suggested that ASEAF ameliorates the insulin resistant state of the diabetic rats. In conclusion, ASEAF could be developed into a potential antidiabetic agent for the management of type 2 diabetes. PMID:23606892

Tan, Kok Keong; Kim, Kah Hwi

2013-01-01

17

Induction of HL60 apoptosis by ethyl acetate extract of Cordyceps sinensis fungal mycelium  

Microsoft Academic Search

The cultivated mycelium of a Cordyceps sinensis (Cs) fungus was sequentially extracted by petroleum ether, ethyl acetate (EtOAc), ethanol and water. The EtOAc extract showed the most potent cytotoxic effect against the proliferation of human premyelocytic leukemia cell HL-60, with an ED50 ? 25 ?g\\/ml for 2-day treatment. The EtOAc extract induced the characteristic apoptotic symptoms in the HL-60 cells,

Qiaoxia Zhang; Jianyong Wu; Zongding Hu; Duan Li

2004-01-01

18

Performance of a composite membrane bioreactor for the removal of ethyl acetate from waste air  

Microsoft Academic Search

Ethyl acetate removal from an air stream was carried out by using a flat composite membrane bioreactor. The composite membrane consisted of a dense polydimethylsiloxane top layer with an average thickness of 0.3?m supported in a porous polyacrylonitrile layer (50?m). The membrane bioreactor (MBR) was operated during 3months, and a maximum elimination capacity of 225gm?3h?1 at an empty bed residence

F. J. Álvarez-Hornos; D. Volckaert; P. M. Heynderickx; H. Van Langenhove

2011-01-01

19

Influence of moisture on the crystal forms of niclosamide obtained from acetone and ethyl acetate  

Microsoft Academic Search

The purpose of this study was to elucidate the formation of crystal hydrates of niclosamide and to delineate the effect of\\u000a relative humidity on the crystal forms obtained from acetone and ethyl acetate. Recrystallization of niclosamide was performed\\u000a in the presence and absence of moisture. Two hydrates and their corresponding anhydrates were isolated. The hydrates obtained\\u000a by the process of

Rahul V. Manek; William M. Kolling

2004-01-01

20

Low-Temperature Complete Oxidation of Ethyl Acetate Over CeO 2 -Supported Precious Metal Catalysts  

Microsoft Academic Search

Catalytic combustion of ethyl acetate was investigated over various CeO2-supported precious metal catalysts prepared by impregnation method, and the effect of reduction treatment on the activity\\u000a was examined. Among the catalysts tested, Ru\\/CeO2 achieved the highest activity for ethyl acetate combustion, and the activity was almost unchanged by the heat treatment in\\u000a a hydrogen atmosphere. In the cases of Pt\\/CeO2,

Tomohiro Mitsui; Toshiaki Matsui; Ryuji Kikuchi; Koichi Eguchi

2009-01-01

21

Effects of the Ethyl Acetate Fraction of Alchornea triplinervia on Healing Gastric Ulcer in Rats  

PubMed Central

Alchornea triplinervia (Spreng.) Muell. Arg (Euphorbiaceae) is a medicinal plant commonly used by people living in the Cerrado region of Brazil to treat gastrointestinal ulcers. We previously described the gastroprotective action of methanolic extract (ME) of Alchornea triplinervia and the ethyl acetate fraction (EAF) in increasing of prostaglandin E2 (PGE2) gastric levels in the mucosa. In this work we evaluated the effect of EAF in promoting the healing process in rats with acetic acid-induced gastric ulcers. In addition, toxicity was investigated during treatment with EAF. After 14 days of treatment with EAF, the potent stimulator of gastric cell proliferation contributed to the acceleration of gastric ulcer healing. Upon immunohistochemical analysis, we observed a pronounced expression of COX-2, mainly in the submucosal layer. The 14-day EAF treatment also significantly increased the number of neutrophils in the gastric mucosa regeneration area. The EAF induced angiogenesis on gastric mucosa, observed as an increase of the number of blood vessels supplying the stomach in rats treated with EAF. Oral administration for 14 days of the ethyl acetate fraction from Alchornea triplinervia accelerated the healing of gastric ulcers in rats by promoting epithelial cell proliferation, increasing the number of neutrophils and stimulation of mucus production. This fraction, which contained mainly phenolic compounds, contributed to gastric mucosa healing.

Lima, Zeila P.; Bonamin, Flavia; Calvo, Tamara R.; Vilegas, Wagner; Santos, Lourdes C.; Rozza, Ariane L.; Pellizzon, Claudia H.; Rocha, Lucia R. M.; Hiruma-Lima, Clelia A.

2011-01-01

22

Analgesic and antiinflammatory activities of the ethyl acetate fraction of Bidens pilosa (Asteraceae).  

PubMed

Bidens pilosa is an Asteraceae widely used in traditional medicine for the treatment of various ailments including pain and inflammation. The present work was undertaken to assess the analgesic and antiinflammatory properties of the ethyl acetate fraction of methylene chloride/methanol (1:1) extract of leaves of Bidens pilosa at the gradual doses of 50, 100 and 200 mg/kg in mice and rats, respectively. The analgesic properties of Bidens pilosa were investigated using the acetic acid writhing, hot plate, capsaicin and formalin-induced pain models. This was followed by a study of the antiinflammatory properties using carrageenan, dextran, histamine and serotonin to induce acute inflammation in rat hind paw. The extract provided a significant (p < 0.01) reduction in pain induced by all four models of nociception. It also presented significant (p < 0.05) antiinflammatory activity in all four models of acute inflammation. These results show that the ethyl acetate fraction of methylene chloride/methanol (1:1) of Bidens pilosa has both analgesic and antiinflammatory properties. The qualitative analysis of the fraction by the high-performance liquid chromatography (HPLC) fingerprint revealed the presence of two flavonoids, namely quercetin and iso-okanin, known to have antiinflammatory and antinociceptive properties, which could be responsible for the analgesic and antiinflammatory effects observed. PMID:24242914

Fotso, Aurélien Fotso; Longo, Frida; Djomeni, Paul Désiré Dzeufiet; Kouam, Siméon Fogue; Spiteller, Michael; Dongmo, Alain Bertrand; Savineau, J P

2014-04-01

23

Simulating the vibrational spectra of ionic liquid systems: 1-ethyl-3-methylimidazolium acetate and its mixtures.  

PubMed

The vibrational spectra of the ionic liquid 1-ethyl-3-methylimidazolium acetate and its mixtures with water and carbon dioxide are calculated using ab initio molecular dynamics simulations, and the results are compared to experimental data. The new implementation of a normal coordinate analysis in the trajectory analyzer TRAVIS is used to assign the experimentally observed bands to specific molecular vibrations. The applied computational approaches prove to be particularly suitable for the modeling of bulk phase effects on vibrational spectra, which are highly important for the discussion of the microscopic structure in systems with a strong dynamic network of intermolecular interactions, such as ionic liquids. PMID:25028030

Thomas, Martin; Brehm, Martin; Hollóczki, Oldamur; Kelemen, Zsolt; Nyulászi, László; Pasinszki, Tibor; Kirchner, Barbara

2014-07-14

24

Simulating the vibrational spectra of ionic liquid systems: 1-Ethyl-3-methylimidazolium acetate and its mixtures  

NASA Astrophysics Data System (ADS)

The vibrational spectra of the ionic liquid 1-ethyl-3-methylimidazolium acetate and its mixtures with water and carbon dioxide are calculated using ab initio molecular dynamics simulations, and the results are compared to experimental data. The new implementation of a normal coordinate analysis in the trajectory analyzer TRAVIS is used to assign the experimentally observed bands to specific molecular vibrations. The applied computational approaches prove to be particularly suitable for the modeling of bulk phase effects on vibrational spectra, which are highly important for the discussion of the microscopic structure in systems with a strong dynamic network of intermolecular interactions, such as ionic liquids.

Thomas, Martin; Brehm, Martin; Hollóczki, Oldamur; Kelemen, Zsolt; Nyulászi, László; Pasinszki, Tibor; Kirchner, Barbara

2014-07-01

25

Protective Effect of Ethyl Acetate Fraction of Stereospermum Suaveolens Against Hepatic Oxidative Stress in STZ Diabetic Rats  

PubMed Central

Stereospermum suaveolens is a folk remedy for the treatment of diabetes and liver disorders in southern parts of India. In the present study, the protective effect of the ethyl acetate fraction of ethanol extract from S. suaveolens against hepatic oxidative stress was evaluated in streptozotocin (STZ)-induced diabetic rats for 14 days. The ethyl acetate fraction was administered orally to the STZ diabetic rats at the doses of 200 and 400 mg/kg. Blood glucose level was measured according to glucose oxidase method. In order to determine hepatoprotective activity, changes in the levels of serum biomarker enzymes such as aspartate transaminase (AST), alanine transaminase (ALT), and serum alkaline phosphatase (SALP) were assessed in the ethyl acetate fraction treated diabetic rats and were compared with the levels in diabetic control rats. In addition, the antioxidant activity of ethyl acetate fraction was evaluated using various hepatic parameters such as thiobarbituric acid reactive substances (TBARS), reduced glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT). It was found that administration of ethyl acetate fraction (200 and 400 mg/kg) produced a significant (P < 0.001) fall in fasting blood glucose level, TBARS, bilirubin, AST, ALT, and SALP, while elevating the GSH levels, and SOD and CAT activities in diabetic rats. Histopathologic studies also revealed the protective effect of ethyl acetate fraction on the liver tissues of diabetic rats. It was concluded from this study that the ethyl acetate fraction from ethanol extract of S. suaveolens modulates the activity of enzymatic and nonenzymatic antioxidants and enhances the defense against hepatic oxidative stress in STZ-induced diabetic rats. PMID:24716175

Balasubramanian, Thirumalaiswamy; Senthilkumar, G. P; Karthikeyan, M.; Chatterjee, Tapan Kumar

2013-01-01

26

Ethyl Acetate Extract of Artemisia anomala S. Moore Displays Potent Anti-Inflammatory Effect  

PubMed Central

Artemisia anomala S. Moore has been widely used in China to treat inflammatory diseases for hundreds of years. However, mechanisms associated with its anti-inflammatory effect are not clear. In this study, we prepared ethyl acetate, petroleum ether, n-BuOH, and aqueous extracts from ethanol extract of Artemisia anomala S. Moore. Comparing anti-inflammatory effects of these extracts, we found that ethyl acetate extract of this herb (EAFA) exhibited the strongest inhibitory effect on nitric oxide (NO) production in LPS/IFN?-stimulated RAW264.7 cells. EAFA suppressed the production of NO in a time- and dose-dependent manner without eliciting cytotoxicity to RAW264.7 cells. To understand the molecular mechanism underlying EAFA's anti-inflammatory effect, we showed that EAFA increased total cellular anti-oxidant capacity while reducing the amount of inducible nitric oxide synthase (iNOS) in stimulated RAW264.7 cells. EAFA also suppressed the expression of IL-1? and IL-6, whereas it elevates the level of heme oxygenase-1. These EAFA-induced events were apparently associated with NF-?B and MAPK signaling pathways because the DNA binding activity of p50/p65 was impaired and the activities of both ERK and JNK were decreased in EFEA-treated cells comparing to untreated cells. Our findings suggest that EAFA exerts its anti-inflammatory effect by inhibiting the expression of iNOS. PMID:24744815

Tan, Xi; Wang, Yuan-Lai; Yang, Xiao-Lu; Zhang, Dan-Dan

2014-01-01

27

Antifungal and antioxidant activity of Crassocephalum bauchiense (Hutch.) Milne-Redh ethyl acetate extract and fractions (Asteraceae)  

PubMed Central

Background Crassocephalum bauchiense is a flowering plant, found in the West Region of Cameroon. Previous studied has highlighted the antibacterial and the dermal toxicological safety as well as the immunomodulatory activities of the ethyl acetate extract of its dry leaves. As an extension of the previous researches, the current work has been undertaken to evaluate the in vitro antifungal and antioxidant activities of C. bauchiense dried leaves ethyl acetate extract and fractions. Methods The extract was obtained by maceration in ethyl acetate and further fractionated into six fractions labeled F1 to F6 by flash chromatography. The antifungal activity of the extract and fractions against yeasts and dermatophytes was evaluated using broth microdilution method. Antioxidant activity was evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH), nitric oxide (NO) and ?-carotene - linoleic acid assays. Results The extract (MIC = 0.125 - 4 mg/ml) was found to be more active on dermatophytes and yeasts compared to the fractions. The ethyl acetate extract and fractions exhibited strong scavenging activity on DPPH (CI50 = 28.57 - 389.38 ?g/ml). The fractions F3 and F6 expressed best antioxidant activity on DPPH radicals compared to the crude extract. Conclusion The results of these findings clearly showed that C. bauchiense ethyl acetate extract has a significant antifungal and antioxidant activity. It is therefore a source of active compounds that might be used as antifungal and antioxidant agents. PMID:24742210

2014-01-01

28

Acetone and Ethyl Acetate in Commercial Nail Polish Removers: A Quantitative NMR Experiment Using an Internal Standard  

NASA Astrophysics Data System (ADS)

The qualitative and quantitative analysis of commercial nail polish removers is performed on a 60 MHz NMR spectrometer. After taking NMR spectra of the polish removers, students can make peak assignments for the known components of acetone and ethyl acetate. Using these spectra, students are also able to identify the unknown alcohol present in the remover as ethanol. Quantitative analysis of either the acetone or ethyl acetate in the nail polish removers is accomplished by comparing the analyte peak intensities with that of an internal standard. The system in which deuterated acetone is used as a solvent and methylene chloride as an internal standard gave precise results for both commercial removers and for standards prepared from pure acetone or an ethyl acetate/ethanol mixture. As recovery from the standards was approximately 96 - 98% of what was anticipated, the analysis of the commercial products is also believed to be accurate.

Clarke, David W.

1997-12-01

29

Phase behavior of CO2 in room-temperature ionic liquid 1-ethyl-3-ethylimidazolium acetate.  

PubMed

Carbon dioxide solubility (vapor-liquid equilibria: VLE) in an ionic liquid, 1-ethyl-3-ethylimidazolium acetate ([eeim][Ac]) was measured using a gravimetric microbalance at four isotherms (about 283, 298, 323, and 348 K) up to about 2 MPa. An equation-of-state (EOS) model was used to analyze the VLE data and has predicted vapor-liquid-liquid equilibria (VLLE: or liquid-liquid separations) in CO(2)-rich solutions. The VLLE prediction was confirmed experimentally using a volumetric method and likely the liquid-liquid equilibria will intersect with the solid-liquid equilibria such that no lower critical solution temperature can exist and the binary system may be classified as Type III phase behavior. Carbon dioxide solubility in the ionic-liquid-rich solution show extremely unusual behavior. CO(2) dissolves in the ionic liquid at large concentrations (up to about 20 mole % of CO(2)) with almost no vapor pressure above the mixtures. This result is similar to our previous findings with 1-butyl-3-methylimidazolium acetate ([bmim][Ac]) and 1-ethyl-3-methylimidazolium acetate ([emim][Ac]). In all three cases the CO(2) forms a molecular complex (or chemical reaction) with the ionic liquid. (13)C NMR spectroscopy has identified the structure for CO(2) absorbed in [eeim][Ac] to be [eeim]-2-carboxylate. Addition of water to the carboxylate leads to the dissolution of CO(2). The thermodynamic excess properties (enthalpy, entropy, and Gibbs energy) for all three systems have been calculated using the EOS and support the complex formation of the type AB(2) (where A is CO(2) and B is ionic liquid). Isothermal differential scanning calorimetry has verified the heat of reaction calculations and found for CO(2) absorbing in [emim][Ac], [eeim][Ac] and [bmim][Ac] to be about -38 kJ mol(-1). Additional experiments have examined the effect of water on the density, viscosity and CO(2) solubility in [eeim][Ac] and the CO(2) solubility in mixtures of [eeim][Ac] with other acetate salts. PMID:22511252

Shiflett, Mark B; Elliott, Beth A; Lustig, Steve R; Sabesan, Subramaniam; Kelkar, Manish S; Yokozeki, A

2012-05-14

30

Microwave-assisted dissolution and delignification of wood in 1-ethyl-3-methylimidazolium acetate.  

PubMed

Microwave irradiation can facilitate the dissolution and delignification of lignocelluloses in ionic liquids compared to simple oil bath heating as demonstrated here where 92.5% of 0.5 g ground southern yellow pine was dissolved in 10 g 1-ethyl-3-methylimidazolium acetate using microwave irradiation in only 4 min. Cellulose-rich material (pulp) regenerated from the wood/ionic liquid solution had a lignin content of ~10%; significantly lower than the lignin content of the original wood (31.9%) or that of pulp obtained from the same experiment but using 16 h of oil bath heating (16-24%). The 10% lignin content obtained with the microwave method was close to that of pulp obtained from the oil bath heating method when polyoxometalate catalysts were used (5-9%). PMID:23566466

Wang, Hui; Maxim, Mirela L; Gurau, Gabriela; Rogers, Robin D

2013-05-01

31

Macroscopic and microscopic study of 1-ethyl-3-methyl-imidazolium acetate-water mixtures.  

PubMed

Mixtures of 1-ethyl-3-methyl-imidazolium acetate ([C2mim][OAc]) and water across the entire composition range, from pure [C2mim][OAc] to pure water, have been investigated using density, viscosity, and NMR spectroscopy, relaxometry, and diffusion measurements. These results have been compared to ideal mixing laws for the microscopic data obtained from the NMR results and macroscopic data through the viscosity and density. It was also found that the mixing of the two fluids is exothermal. The proton spectra indicate though that [C2mim][OAc] and water are interacting without the formation of new compounds. The maximal deviations of experimental data from theoretical mixing rules were all found to occur within the range 0.74 ± 0.06 mol fraction of water, corresponding to approximately three water molecules per [C2mim][OAc] molecule. PMID:23020276

Hall, Craig A; Le, Kim A; Rudaz, Cyrielle; Radhi, Asanah; Lovell, Christopher S; Damion, Robin A; Budtova, Tatiana; Ries, Michael E

2012-10-25

32

Amelioration of cisplatin induced nephrotoxicity in mice by an ethyl acetate extract of Lagerstroemia speciosa (L).  

PubMed

We studied an ethyl acetate (EtoAC) extract of leaves obtained from the medicinal and ornamental tree, Lagerstroemia speciosa L, for nephroprotective activity in cisplatin-induced acute renal injury in Balb/C mice. The EtoAC extract at dose levels of 50 and 250 mg/kg showed a dose-dependent reduction in cisplatin-induced elevations in urea and creatinine concentrations. Additionally, treatment with the EtoAC extract prevented the cisplatin-induced decline of the renal antioxidant enzymes superoxide dismutase, catalase, glutathione peroxidase, and reduced glutathione. The findings suggest that the EtoAC extract from L. speciosa possesses marked nephroprotective activity and could offer a promising role in the treatment of acute renal injury caused by a nephrotoxin like cisplatin. PMID:18380170

Priya, T T; Sabu, M C; Jolly, C I

2007-01-01

33

Influence of water on swelling and dissolution of cellulose in 1-ethyl-3-methylimidazolium acetate.  

PubMed

In this study the effect of residual coagulation medium (water) on cellulose dissolution in an ionic liquid is discussed. Solubility of dissolving grade pulp; HWP and SWP, and microcrystalline cellulose in binary solvents, mixtures of 1-ethyl-3-methyl-imidazolium acetate and water, was investigated by turbidity measurements, light microscopy, rheometry, and CP/MAS (13)C-NMR spectroscopy. The viscoelastic properties of the cellulose solutions imply that residual water affect the cellulose dissolution. However, it is not obvious that this always necessarily poses serious drawbacks for the solution properties or that the effects are as severe as previously believed. Turbidity measurements, viscosity data and crystallinity of the regenerated cellulose correlated well and an increased conversion to cellulose II was found at low water and cellulose contents with an apparent maximum of conversion at 2-5 wt% water. At high water content, above 10 wt%, dissolution and conversion was largely inhibited. PMID:24274528

Olsson, Carina; Idström, Alexander; Nordstierna, Lars; Westman, Gunnar

2014-01-01

34

Enrichment, isolation and characterization of fungi tolerant to 1-ethyl-3-methylimidazolium acetate  

SciTech Connect

This work aims to characterize microbial tolerance to 1-ethyl-3-methylimidazolium acetate ([C2mim][OAc]), ionic liquid that has emerged as a novel biomass pretreatment for lignocellulosic biomass. Enrichment experiments performed using inocula treated with [C2mim][OAc] under solid and liquid cultivation yielded fungal populationsdominated by Aspergilli. Ionic liquid-tolerant Aspergillus isolates from these enrichments were capable of growing in a radial plate growth assay in the presence of 10% [C2mim][OAc]. When a [C2mim][OAc]-tolerant Aspergillus fumigatus strain was grown in the presence of switchgrass, endoglucanases and xylanases were secreted that retained residual enzymatic activity in the presence of 20% [C2mim][OAc]. The results of the study suggest tolerance to ionic liquids is a general property of Aspergilli. Tolerance to an industrially important ionic liquid was discovered in a fungal genera that is widely used in biotechnology, including biomass deconstruction.

Singer, S.W.; Reddy, A. P.; Gladden, J. M.; Guo, H.; Hazen, T.C.; Simmons, B. A.; VanderGheynst, J. S.

2010-12-15

35

High-Performance Liquid Chromatographic Determination of Triptonide, Triptriolide, and Triptophenolide in Ethyl Acetate Extract of Tripterygium Wilfordii Hook F  

Microsoft Academic Search

To monitor the composition of extracts of the Chinese herbal remedy Tripterygium wilfordii Hook F (TwHF), a rapid, selective, and sensitive reverse phase HPLC method was developed for the quantitative determination of some of the major or active diterpenoid components, triptonide (1), triptophenolide (2), and triptriolide (3). Ethyl acetate extracts of TwHF were extracted with chloroform, filtered, and then purified

Yanping Mao; John J. Cai; Xuelian Tao; Li Ma; Peter E. Lipsky

1998-01-01

36

Light scattering and membrane formation studies on polysulfone solutions in NMP and in mixed solvents of NMP and ethyl acetate  

Microsoft Academic Search

The relationship between the characteristics of the polymer dope solution and the skin formation mechanism as well as the performance of the asymmetric membrane has been investigated. The solution characteristics have been studied on the polysulfone (PSf) dope solution as a function of the concentrations of both polymer and the cosolvent, ethyl acetate (EA), by dynamic light scattering. An anomalous

Jongok Won; Yong Soo Kang; Hyun Chae Park; Un Young Kim

1998-01-01

37

Antioxidant effects of ethyl acetate extract of Desmodium gangeticum root on myocardial ischemia reperfusion injury in rat hearts  

Microsoft Academic Search

BACKGROUND: This study aims to evaluate the antioxidant potential of the ethyl acetate extract of Desmodium gangeticum root for cardioprotection from ischemia reperfusion-induced oxidative stress. METHODS: The in vitro antioxidant potential of the extract was in terms of hydroxyl radical scavenging activity, lipid peroxide scavenging activity, nitric oxide scavenging activity and diphenylpicrylhydrazyl radical scavenging activity. The in vivo antioxidant potential

Gino A Kurian; Srilalitha Suryanarayanan; Archana Raman; Jose Padikkala

2010-01-01

38

Acetone and Ethyl Acetate in Commercial Nail Polish Removers: A Quantitative NMR Experiment Using an Internal Standard  

Microsoft Academic Search

The qualitative and quantitative analysis of commercial nail polish removers is performed on a 60 MHz NMR spectrometer. After taking NMR spectra of the polish removers, students can make peak assignments for the known components of acetone and ethyl acetate. Using these spectra, students are also able to identify the unknown alcohol present in the remover as ethanol. Quantitative analysis

David W. Clarke

1997-01-01

39

Preparation and crystal characterization of a polymorph, a monohydrate, and an ethyl acetate solvate of the antifungal fluconazole.  

PubMed

The preparation and solid-state characterization of three crystalline modifications of the antifungal agent fluconazole [2-(2,4-difluorophenyl)-1,3-bis-(1H-124-triazol-1-yl)-propan-2-ol] are reported. Recrystallization of fluconazole from propan-2-ol yielded a polymorph (Form III), whereas the solvents water and ethyl acetate yielded the solvated products fluconazole monohydrate and fluconazole. (ethyl acetate)(0.25), respectively. These species were analyzed by thermogravimetry (TGA), differential scanning calorimetry (DSC), FTIR spectroscopy, powder X-ray diffractometry (PXRD), and single crystal X-ray diffraction. Availability of the hitherto unknown crystal structures facilitated interpretation of the thermal data and clarified previous findings relating to the polymorphism of this compound. Fluconazole was found to exist as a centrosymmetric hydrogen bonded dimer in Form III. For the solvated phases, the solvent locations within the drug host matrices were established as isolated sites for water molecules and constricted channels for ethyl acetate molecules. Desolvation of the monohydrate and ethyl acetate solvate yielded polymorphic Form I. Reference PXRD patterns computed from the refined single-crystal X-ray data for the title compounds are presented. PMID:14762899

Caira, Mino R; Alkhamis, Khouloud A; Obaidat, Rana M

2004-03-01

40

The C-H bond activation in 1-ethyl-3-methylimidazolium acetate-copper(II) acetate-water-air (dioxygen) systems.  

PubMed

Ionic liquid (1-ethyl-3-methylimidazolium acetate, [C2C1im][AcO])-copper(ii) diacetate monohydrate-water-air (O2) systems have been investigated by (13)C NMR, EPR, spectrophotometry, HPLC, and synthetic chemistry methods at different temperatures. The C-H bond activation of [C2C1im](+) with the formation of the unusual dication 1,1'-diethyl-3,3'-dimethyl-2,2'-biimidazolium ([(C2C1im)2](2+)) at 50 °C and 1-ethyl-3-methyl-1H-imidazol-2(3H)-one (C2C1imO) at 50-85 °C was revealed. Two new complexes with the above compounds, [(C2C1im)2][Cu(AcO)4] and Cu2(AcO)4(C2C1imO)2, were isolated from the systems and characterized by X-ray structural analysis. Catalytic cycles with the participation of copper(ii) acetate and dioxygen and the production of [(C2C1im)2](2+) and C2C1imO have been proposed. The catalysis presumably includes the formation of the Cu(II)(O2)Cu(II) active centre with ?-?(2):?(2)-peroxide bridging in analogy with tyrosinase and catechol oxidase activity. PMID:24154681

Shtyrlin, Valery G; Serov, Nikita Yu; Islamov, Daut R; Konkin, Alexander L; Bukharov, Mikhail S; Gnezdilov, Oleg I; Krivolapov, Dmitry B; Kataeva, Ol'ga N; Nazmutdinova, Gulnara A; Wendler, Frank

2014-01-14

41

Antitussive Efficacy and Safety Profile of Ethyl Acetate Fraction of Terminalia chebula  

PubMed Central

Antitussive effects of ethyl acetate fraction of Terminalia chebula on sulphur dioxide (SO2) gas induced cough have been examined in mice. Safety profile of Terminalia chebula was established by determining LD50 and acute neurotoxicity. The result showed that extract of Terminalia chebula dose dependently suppressed SO2 gas induced cough in mice. Terminalia chebula, after i.p. administration at dose level 500?mg/kg, offered maximum cough suppressive effects; that is, number of coughs at 60?min was 12 ± 1.52 (mean ± SEM) as compared to codeine 10?mg/kg; i.p., dextromethorphan 10?mg/kg; i.p., and saline, having frequency of cough 10.375 ± 0.866, 12.428 ± 0.81, and 46 ± 2.61, respectively. LD50 value of Terminalia chebula was approximately 1265?mg/kg, respectively. No sign of neural impairment was observed at antitussive doses of extract. Antitussive effect of Terminalia chebula was partly reversed with treatment by naloxone (3?mg/kg; s.c.) while rimcazole (3?mg/kg; s.c.) did not antagonize its cough suppression activity. This may suggest that opioid receptors partially contribute in antitussive action of Terminalia chebula. Along with this, the possibility of presence of single or multiple mechanisms activated by several different pharmacological actions (mainly anti-inflammatory, antioxidant, spasmolytic, antibacterial, and antiphlegmatic) could not be eliminated. PMID:24024039

Wahab, Abdul; Ayub, Khurshed; Sherkheli, M. Azhar; Khan, Rafeeq Alam; Raza, Mohsin

2013-01-01

42

Effects of Ethyl Acetate Extract of Poncirus trifoliata Fruit for Glucocorticoid-Induced Osteoporosis  

PubMed Central

Poncirus trifoliata fruit (PTF) affects the digestive and cardiovascular systems, and kidney function. The authors studied the effects of ethyl acetate (EtOAc) extract of PTF on the activities of osteoblasts and in an animal model. The main compounds of the EtOAc extract, naringin and poncirin have been confi rmed by HPLC and NMR analysis. Effects of osteoblastic differentiation were mea-sured by alkaline phosphatase (ALP) activity, osteopontin (OPN) protein expression and osteoprotegerin (OPG) mRNA expression in MC3T3-E1 cells. Also, osteoclast differentiation was measured by multinucleated cells (MNCs) formation through tartrate resistance acid phosphatase (TRAP)-positive staining. Bone mineral density (BMD) was measured before and after treatment with EtOAc extract of PTF in prednisolone-induced osteoporotic mice. Dexamethasone (DEX) decreased OPN and OPG expression level in MC3T3-E1 cells and ALP activity was decreased by DEX dose-dependently. EtOAc extract of PTF recovered the levels of ALP activity, and the expression of OPN and OPG in MC3T3-E1 cells treated with DEX. In osteoclast differentiation, multinucleated TRAP-positive cell formation was significantly suppressed by the EtOAc extract of PTF. Total body BMD was restored by EtOAc extract of PTF in prednisolone-induced osteoporotic mice. In conclusion, EtOAc extract of PTF recovered DEX-mediated deteriorations in osteoblastic and osteoclastic functions, and increased BMD in glucocorticoid-induced osteoporosis. PMID:24116280

Yoon, Hyung-Young; Cho, Yun-Seok; Jin, Qinglong; Kim, Hyun-Gyu; Woo, Eun-Rhan; Chung, Yoon-Sok

2012-01-01

43

Influence of cellulose on ion diffusivity in 1-ethyl-3-methyl-imidazolium acetate cellulose solutions.  

PubMed

Solutions of microcrystalline cellulose in 1-ethyl-3-methyl-imidazolium acetate have been investigated using pulsed-field gradient (1)H NMR. In all cases the geometrically larger cation was found to diffuse faster than the smaller anion. Arrhenius temperature analysis has been applied to the ion diffusivities giving activation energies. The diffusion and published viscosity data for these solutions were shown to follow the Stokes-Einstein relationship, giving hydrodynamic radii of 1.6 Å (cation) and 1.8 Å (anion). Theories for obstruction, free-volume and hydrodynamic effects on solvent diffusion have been applied. The Mackie-Meares and Maxwell-Fricke obstruction models provided a correct trend only when assuming a certain fraction of ions are bound to the polymer. From this fraction it was shown that the maximum dissolvable cellulose concentration is ?27% w/w, which is consistent with the highest known prepared concentration of cellulose in this ionic liquid. The Phillies' hydrodynamic model is found to give the best description for the cellulose concentration dependence of the ion diffusivities. PMID:20923202

Lovell, Christopher S; Walker, Adam; Damion, Robin A; Radhi, Asanah; Tanner, Steven F; Budtova, Tatiana; Ries, Michael E

2010-11-01

44

Physical insight into switchgrass dissolution in the ionic liquid 1-ethyl-3-methylimidazolium acetate  

SciTech Connect

Small-angle neutron scattering was used to characterize solutions of switchgrass and the constituent biopolymers cellulose, hemicellulose, and lignin, as well as a physical mixture of them mimicking the composition of switchgrass, dissolved in the ionic liquid (IL) 1-ethyl-3-methylimidazolium acetate. The results demonstrate that the IL dissolves the cellulose fibrils of switchgrass, although a supramolecular biopolymer network remains that is not present in solutions of the individual biopolymers and that does not self-assemble in a solution containing the physical mixture of the individual biopolymers. The persistence of a network-like structure indicates that dissolving switchgrass in the IL does not disrupt all of the physical entanglements and covalent linkages between the biopolymers created during plant growth. Reconstitution of the IL-dissolved switchgrass yields carbohydrate-rich material containing cellulose with a low degree of crystallinity, as determined by powder X-ray diffraction, which impacts potential down-stream uses of the biopolymers produced by the process. The data suggests that the use of chemical additives which would break bonds that exist between the lignin and hemicellulose might improve the purity of the resulting product, but may not be able to disrupt the highly physically-entangled biopolymer network sufficiently to facilitate their separation.

Wang, Hui [University of Alabama, Tuscaloosa] [University of Alabama, Tuscaloosa; Gurau, Gabriela [University of Alabama, Tuscaloosa] [University of Alabama, Tuscaloosa; Pingali, Sai Venkatesh [ORNL] [ORNL; O'Neil, Hugh [ORNL] [ORNL; Evans, Barbara R [ORNL] [ORNL; Urban, Volker S [ORNL] [ORNL; Heller, William T [ORNL] [ORNL; Rogers, Robin D [University of Alabama, Tuscaloosa] [University of Alabama, Tuscaloosa

2014-01-01

45

Antioxidant and antimicrobial activities of ethyl acetate extract, fractions and compounds from stem bark of Albizia adianthifolia (Mimosoideae)  

PubMed Central

Background Albizia adianthifolia is used traditionally in Cameroon to treat several ailments, including infectious and associated diseases. This work was therefore designed to investigate the antioxidant and antimicrobial activities of ethyl acetate extract, fractions and compounds isolated from the stem bark of this plant. Methods The plant extract was prepared by maceration in ethyl acetate. Its fractionation was done by column chromatography and the structures of isolated compounds were elucidated using spectroscopic data in conjunction with literature data. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) and trolox equivalent antioxidant capacity (TEAC) assays were used to detect the antioxidant activity. Broth micro-dilution method was used for antimicrobial test. Total phenol content was determined spectrophotometrically in the extracts by using Folin–Ciocalteu method. Results The fractionation of the extract afforded two known compounds: lupeol (1) and aurantiamide acetate (2) together with two mixtures of fatty acids: oleic acid and n-hexadecanoic acid (B1); n-hexadecanoic acid, octadecanoic acid and docosanoic acid (B2). Aurantiamide acetate was the most active compound. The total phenol concentration expressed as gallic acid equivalents (GAE) was found to vary from 1.50 to 13.49??g/ml in the extracts. The antioxidant activities were well correlated with the total phenol content (R2?=?0.946 for the TEAC method and R2?=?0.980 for the DPPH free-radical scavenging assay). Conclusions Our results clearly reveal that the ethyl acetate extract from the stem bark of A. adianthifolia possesses antioxidant and antimicrobial principles. The antioxidant activity of this extract as well as that of compound 2 are being reported herein for the first time. These results provide promising baseline information for the potential use of this plant as well as compound 2 in the treatment of oxidative damage and infections associated with the studied microorganisms. PMID:22809287

2012-01-01

46

Coagulation of chitin and cellulose from 1-ethyl-3-methylimidazolium acetate ionic-liquid solutions using carbon dioxide.  

PubMed

Chemisorption of carbon dioxide by 1-ethyl-3-methylimidazolium acetate ([C2 mim][OAc]) provides a route to coagulate chitin and cellulose from [C2 mim][OAc] solutions without the use of high-boiling antisolvents (e.g., water or ethanol). The use of CO2 chemisorption as an alternative coagulating process has the potential to provide an economical and energy-efficient method for recycling the ionic liquid. PMID:24115399

Barber, Patrick S; Griggs, Chris S; Gurau, Gabriela; Liu, Zhen; Li, Shan; Li, Zengxi; Lu, Xingmei; Zhang, Suojiang; Rogers, Robin D

2013-11-18

47

Antioxidant and Protective Effect of Ethyl Acetate Extract of Podophyllum Hexandrum Rhizome on Carbon Tetrachloride Induced Rat Liver Injury  

PubMed Central

The antioxidant and hepatoprotective activities of ethyl acetate extract was carefully investigated by the methods of DPPH radical scavenging activity, Hydroxyl radical scavenging activity, Superoxide radical scavenging activity, Hydrogen peroxide radical scavenging activity and its Reducing power ability. All these in vitro antioxidant activities were concentration dependent which were compared with standard antioxidants such as BHT, ?-tocopherol. The hepatoprotective potential of Podophyllum hexandrum extract was also evaluated in male Wistar rats against carbon tetrachloride (CCl4)-induced liver damage. Pre-treated rats were given ethyl acetate extract at 20, 30 and 50?mg/kg dose prior to CCl4 administration (1?ml/kg, 1:1 in olive oil). Rats pre-treated with Podophyllum hexandrum extract remarkably prevented the elevation of serum AST, ALT, LDH and liver lipid peroxides in CCl4-treated rats. Hepatic glutathione levels were significantly increased by the treatment with the extract in all the experimental groups. The extract at the tested doses also restored the levels of liver homogenate enzymes (glutathione peroxidase, glutathione reductase, superoxide dismutase and glutathione-S- transferase) significantly. This study suggests that ethyl acetate extract of P. hexandrum has a liver protective effect against CCl4-induced hepatotoxicity and possess in vitro antioxidant activities. PMID:21394192

Ganie, Showkat Ahmad; Haq, Ehtishamul; Masood, Akbar; Hamid, Abid; Zargar, Mohmmad Afzal

2011-01-01

48

The antihypertensive effect of ethyl acetate extract from red raspberry fruit in hypertensive rats  

PubMed Central

Objectives: To evaluate the antihypertensive effect of Xinjiang red raspberry fruit ethyl acetate extract (EER) on spontaneously hypertensive rats (SHR) and its possible mechanism from antioxidant perspective. Materials and Methods: The SHR rats were randomly divided into 3 groups, and treated with EER low dose (EERL, 100 mg/kg/d), high dose (EERH, 200 mg/kg/d), and water (SHR) through gastric gavage daily for 5 weeks. Another 8 age-matched male Wistar–Kyoto rats were used as normotensive group (WKY). The systolic blood pressure (SBP) was measured by noninvasive tail-cuff method once a week. At the end of the treatment, blood samples were collected and serum concentrations of nitric oxide (NO), superoxide dismutase (SOD), malondialchehyche (MDA), and plasma endothelin (ET) were determined. Results: Treatment of SHR rats with EER lowered the blood pressure compared with that treated with water (SHR), and the high dose showed more significant reduction in blood pressure. Treatment of SHR rats with EER increased serum NO and SOD levels and lowered ET and MDA levels. As compared with control group, NO levels were increased significantly in EERL (P < 0.01), SOD was elevated more significantly in both EERL and EERH (P < 0.01); MDA was decreased significantly in EERH group (P < 0.05), whereas plasma ET decreased more significantly in the EERH group (P < 0.05). Conclusions: The red raspberry extracts demonstrated a dose-dependent antihypertensive effects in SHR and this may be related to increased NO activation and improved vascular endothelial dysfunction via antioxidation. These results confirmed that raspberries rich in polyphenols have potential cardiovascular protective effects. PMID:21472074

Jia, Han; Liu, Ji Wen; Ufur, Halmurat; He, Geng Sheng; Liqian, Hai; Chen, Peipei

2011-01-01

49

Investigation of Pulsed Electric Field (PEF) as an Intensification Pretreatment for Solvent Lipid Extraction from Microalgae, utilizing Ethyl Acetate as a Greener Substitute to Chloroform-based Extraction  

E-print Network

two significant challenges: green solvent selection with efficient extractive characteristics and requirement of cell disruption pretreatment. In this contribution, the utilization of ethyl acetate-based solvents is suggested as a green alternative...

Antezana Zbinden, Mauricio Daniel R.

2011-02-16

50

DESOXYCORTICOSTERONE ACETATE  

PubMed Central

1. Desoxycorticosterone acetate (DCA) and NaCl, in the dosage employed in normal rats, caused renal and cardiac hypertrophy, characteristic changes in the renal tubular epithelium, atrophic changes in the subcapsular zone of the adrenal cortex, and serum electrolyte changes characterized by a rise in sodium and fall in potassium. 2. In rats rendered nephritic with a rabbit anti-rat-kidney serum, the same regimen caused similar changes. In addition, DCA given concurrently with NaCl greatly intensified the nephritic process and gave rise to striking arterial hypertension. 3. A diet, virtually sodium-free, administered to normal and nephritic rats receiving daily injections of DCA abolished or reduced to a minimum the effects of this steroid; i.e., a liberal ingestion of NaCl was essential for the potentiation of the action of DCA. 4. The addition of KCl to the drinking water of rats receiving DCA and NaCl tended to correct the depression of the level of potassium in the serum, but had no effect upon the hypertension in nephritic animals nor upon the anatomical lesions. 5. The mechanism by which the sodium ion potentiates the activity of DCA has not been established. PMID:19871607

Knowlton, Abbie I.; Loeb, Emily N.; Stoerk, Herbert C.; Seegal, Beatrice C.

1947-01-01

51

Constructing a polyfunctional zeolite-encaged metal catalyst for the multistage oxidation of ethanol into ethyl acetate  

SciTech Connect

To construct an efficient polyfunctional catalyst for the given multistage reaction, the authors previously studied the catalysts HNaY, clinosorb, H-clinoptilolite, and H-mordenite in the reaction of esterification of ethanol with acetic acid; CuH-clinoptilolite, Cu-clinosorb, CuH-mordenite, and CuHNaY in the reaction of oxidative dehydration of ethanol; PdH-clinoptilolite, Pd-clinosorb, PdH-mordenite, and PdHNaY in the oxidation of ethanol; and CuPdH-clinoptilolite in the oxidative transformation of ethanol into ethyl acetate. The catalytic activity of these zeolites and other Pd- and Cu-containing zeolite catalysts, which the authors synthesized by the ion-exchange technique, was studied in a flow-circulating set-up.

Shakhtakhtinskii, T.N.; Aliev, A.M.; Kuliev, A.R. [Institute of Theoretical Problems of Chemical Technology, Baku (Azerbaijan)

1995-08-01

52

Phytochemical analysis and antibacterial evaluation of the ethyl acetate extract of the stem bark of Bridelia micrantha  

PubMed Central

Background Plant cells fundamentally are chemical factories containing a rich supply of therapeutically useful phytocompounds that have the potential of being developed into potent antimicrobial agents. Aim of the Study: To investigate the antibacterial activity of fractionated extracts of the ethyl acetate extract of the stem bark of Bridelia micrantha (Hochst., Baill., Euphorbiaceae). Materials and Methods: Thin-layer chromatography and column chromatography were used to purify the extracts and antimicrobial activity performed on reference and clinical strains of Staphylococcus aureus, Shigella sonnei, Salmonella Typhimurium, and Helicobacter pylori using direct and indirect bioautographic methods respectively. Furthermore, the eluted compound fractions were then assayed for minimum inhibitory concentration (MIC50) using the 96-well micro dilution technique. Results: Better separation of phytocompounds was obtained from the non-polar Benzene/Ethanol/Ammonia (BEA) and intermediate-polar Chloroform/Ethyl acetate/Formic acid (CEF) eluents compared to the polar Ethanol/Methanol/Water (EMW). Bioautography revealed the presence of three bioactive compounds (Rf values; 0.12, 0.20, and 0.42) on the BEA plates, designated fractions 3, 7, and 8 with MIC50 values; 0.0048mg/mL to 1.25mg/mL (fraction 3), 0.0024mg/mL to 5 mg/mL (fraction 7), and 0.0024mg/mL to 2.5mg/mL (fraction 8). Conclusion: Our findings demonstrate that ethyl acetate extract of the stem-bark of B. micrantha possess potent bioactive phytocompounds that may be developed into new antimicrobials. PMID:23661993

Adefuye, Anthonio O.; Ndip, Roland N.

2013-01-01

53

Antibacterial and dermal toxicological profiles of ethyl acetate extract from Crassocephalum bauchiense (Hutch.) Milne-Redh (Asteraceae)  

PubMed Central

Background The emergence in recent years of numerous resistant strains of pathogenic bacteria to a range of formerly efficient antibiotics constitutes a serious threat to public health. Crassocephalum bauchiense, a medicinal herb found in the West Region of Cameroon is used to treat gastrointestinal infections as well as liver disorders. The ethyl acetate extract from the leaves of C. bauchiense was evaluated for its antibacterial activity as well as acute and sub-acute toxicities. Methods The plant extract was prepared by maceration in ethyl acetate. Its phytochemical screening was done by standard methods. The broth microdilution method was used to evaluate the in vitro antibacterial activity. The in vivo antibacterial activity of a gel formulation (0.05, 1 and 2% w/v) of this extract was evaluated using a Staphylococcus aureus-induced dermatitis in a murine model. Selected haematological and biochemical parameters were used to evaluate the dermal sub-acute toxicity of the extract in rats. Results Phytochemical screening of the C. bauchiense extract revealed the presence of alkaloids, phenols, tannins and sterols. In vitro antibacterial activities were observed against all the tested microorganisms (MIC = 0.04-6.25 mg/ml). Formulated extract-gel (2% w/v) and gentamycin (reference drug) eradicated the microbial infection after five days of treatment. A single dermal dose of this extract up to 32 g/kg body weight (bw) did not produce any visible sign of toxicity. Also, daily dermal application of the C. bauchiense extract gel formulation for 28 days did not show any negative effect, instead some biochemical parameters such as alanine aminotransferase (ALT and AST), low density lipoprotein (LDL), high density lipoprotein (HDL) and triglycerides were significantly (p < 0.05) affected positively. Conclusion These results indicate that the C. bauchiense ethyl acetate extract can be used safely for the treatment of some bacterial infections. PMID:21615960

2011-01-01

54

Ethyl acetate as an acyl donor in the continuous flow kinetic resolution of (±)-1-phenylethylamine catalyzed by lipases.  

PubMed

The synthesis of chiral amines is still a challenge for organic synthesis since optically pure amines are of great importance for the pharmaceutical and agrochemical industries. Among all the methodologies developed until now, chemoenzymatic dynamic kinetic resolution has proven to be useful for the preparation of enantioenriched primary chiral amines. In our continuous efforts toward the development of a continuous flow process, herein we report our results on the continuous flow kinetic resolution of (±)-1-phenylethylamine leading to the desired products with high enantiomeric ratios (>200) and short residence times (40 minutes) using ethyl acetate as the acyl donor. PMID:23558581

de Miranda, Amanda S; Miranda, Leandro S M; de Souza, Rodrigo O M A

2013-05-28

55

The effects of chloroform, ethyl acetate and methanolic extracts of Brassica rapa L. on cell-mediated immune response in mice  

PubMed Central

Turnips with a long history of usage, are helpful in preventing breast and prostate cancer, inflammation and body`s immune system dysfunction. In this study, we investigated the effects of chloroform, ethyl acetate and methanolic extracts of Brassica rapa L. on cell-mediated immune response in mice. Chloroform, ethyl acetate and methanolic extracts of B. rapa glands were prepared by maceration method. To study the effects of B. rapa on acquired immunity, groups of Balb/c mice (n=8) were used. Sheep red blood cell (SRBC) was injected (s.c., 1×108cells/ml, 0.02 ml) and 5 days later, different extracts (10, 100 and 500 mg/kg), betamethasone (4 mg/kg) and Levamisol (4 mg/kg) as a positive control and normal saline as a negative control were given i.p. After 1 h SRBC was injected to footpad (s.c., 1×108cells/ml, 0.02 ml) and footpad swelling was measured up to 72 h. To investigate the effects of B. rapa on innate immunity the same procedure was used, but animals only received one injection of SRBC 1 h after i.p. injection of test compounds. Our findings showed that SRBC induced an increase in paw swelling with maximum response at 6-8 and 2-4 h for innate and acquired immunity, respectively. Betamethasone inhibited and levamisol increased paw thickness in both models. In both innate and acquired immunity models, chloroform, ethyl acetate and methanolic extracts of B. rapa glands significantly and dose-dependently reduced paw thickness. Ethyl acetate extract showed better effect. As glucosinolates are better extracted by ethyl acetate, it may be concluded that they are contributed in the more pronounced effects of ethyl acetate extract. PMID:24019825

Jafarian-Dehkordi, A.; Zolfaghari, B.; Mirdamadi, M.

2013-01-01

56

Effect of the ionic liquid 1-ethyl-3-methylimidazolium acetate on the phase transition of starch: dissolution or gelatinization?  

PubMed

This work revealed that the interactions between starch, the ionic liquid 1-ethyl-3-methylimidazolium acetate ([Emim][OAc]), and water might contribute to the phase transition (gelatinization, dissolution, or both) of native starch at reduced temperature. Using mixtures of water and [Emim][OAc] at certain ratios (7.2/1 and 10.8/1 mol/mol), both the gelatinization and dissolution of the starch occur competitively, but also in a synergistic manner. At lower [Emim][OAc] concentration (water/[Emim][OAc] molar ratio?25.0/1), mainly gelatinization occurs which is slightly impeded by the strong interaction between water and [Emim][OAc]; while at higher [Emim][OAc] concentration (water/[Emim][OAc] molar ratio?2.8/1), the dissolution of starch is the major form of phase transition, possibly restricted by the difficulty of [Emim][OAc] to interact with starch. PMID:23544570

Mateyawa, Sainimili; Xie, David Fengwei; Truss, Rowan W; Halley, Peter J; Nicholson, Timothy M; Shamshina, Julia L; Rogers, Robin D; Boehm, Michael W; McNally, Tony

2013-04-15

57

Mössbauer study of iron-based perovskite-type materials as potential catalysts for ethyl acetate oxidation  

NASA Astrophysics Data System (ADS)

La-Sr-Fe perovskite-type oxides were prepared by the nitrate-citrate method. The basic object of this study is layered Ruddlesden-Popper phase LaSr3Fe3O10. The phase composition and structural properties of the obtained materials are investigated by Mössbauer spectroscopy, X-ray diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS) and temperature programmed reduction (TPR). The preliminary catalytic tests show a high potential of these materials for volatile organic compounds (VOCs) elimination as they possess high conversion ability and selectivity to total oxidation of ethyl acetate. Catalytic performance of LaSr3Fe3O10 is depended on the stability of structure and Fe4+-oxidation state.

Paneva, D.; Dimitrov, M.; Velinov, N.; Kolev, H.; Kozhukharov, V.; Tsoncheva, T.; Mitov, I.

2010-03-01

58

In-vivo Antioxidant Effects of Ethyl Acetate Fraction of Mentha spicata L. on 4-Nitroquinoline-1-Oxide Injected Mice.  

PubMed

Antioxidant effects of ethyl acetate fraction of Mentha spicata (L.) were evaluated against 4-nitroquinoline-1-oxide injected mice. For this study, experiment setup consisted of 36 albino mice of either sex divided into 6 groups: Control (25% DMSO in water), ethyl acetate fraction (EAF) alone group (80, 160 mg/Kg body weight-bwt), 4-NQO (7.5 mg/Kg bwt-IP) alone and 4-NQO + EAF. EAF and vehicles were administered orally for five consecutive days. 4-NQO (7.5 mg/Kg bwt) was injected intraperitoneally on the 6(th) day. After 24 h, the animals were killed; liver sample was extracted and used for bio-assay. 4-NQO alone treated group decreased (27-60%) the antioxidant activities and promoted lipid peroxidation (LPO-60%) over their respective control values. Pretreatment with EAF, at the maximum dose (160 mg/Kg bwt) brought down the LPO up to 87% enhanced by 4-NQO. Among the enzymatic antioxidants, glutathione S-transferase (GST) was the most affected enzyme with 4-NQO and the least was catalase (CAT). Pretreatment with EAF (160 mg/Kg bwt), the restoration of antioxidants like glutathione peroxidase, superoxide dismutase, and CAT were found equal or less than 1.2 fold higher than that of the respective control values whereas, GST was observed to be the most restored antioxidant. Be reduced glutathione (GSH) and the least vitamin C over their control values. EAF restored the GSH and Vitamin E levels were found to be 1.2 fold higher than the respective control values. PMID:24250414

Arumugam, Ponnan; Ramesh, Arabandi

2011-01-01

59

Crude ethyl acetate extract of marine microalga, Chaetoceros calcitrans, induces Apoptosis in MDA-MB-231 breast cancer cells  

PubMed Central

Background: Marine brown diatom Chaetoceros calcitrans and green microalga Nannochloropsis oculata are beneficial materials for various applications in the food, nutraceutical, pharmaceutical and cosmeceutical industries. Objective: This study investigated cytotoxicity of different crude solvent extracts from C. calcitrans and N. oculata against various cancer cell lines. Materials and Methods: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was carried out to screen the cytotoxic effects of hexane (Hex), dichloromethane (DCM), ethyl acetate, and methanol extract from C. calcitrans and N. oculata toward various cancer cell lines. Flow cytometry cell cycle was used to determine the cell cycle arrest while the mode of cell death was investigated through acridine orange/propidium iodide (AOPI) staining, Annexin V-Fluorescein Isothiocyanate (FITC) and Terminal deoxynucleotidyl transferase-mediated d-UTP Nick End Labeling (TUNEL) assays. Expression profile of apoptotic and proliferative-related genes was then determined using the multiplex gene expression profiler (GeXP). Results: Crude ethyl acetate (CEA) extract of C. calcitrans inhibited growth of MDA-MB-231 cells, with IC50 of 60 ?g/mL after 72 h of treatment. Further studies were conducted to determine the mode of cell death at various concentrations of this extract: 30, 60 and 120 ?g/mL. The mode of cell death was mainly apoptosis as shown through apoptosis determination test. The expression data from GeXP showed that caspase-4 was upregulated while B-cell leukemia/lymphoma 2(Bcl-2) was down regulated. Thus, caspase-4 induction endoplasmic reticulum death pathway is believed to be one of the mechanisms underlying the induction of apoptosis while Bcl-2 induced S and G2/M cell cycle phase arrest in MDA-MB-231 cells. Conclusion: CEA extract of C. calcitrans showed the highest cytotoxicity on MDA-MB-231 via apoptosis. PMID:24696543

Goh, Su Hua; Alitheen, Noorjahan Banu Mohamed; Yusoff, Fatimah Md; Yap, Swee Keong; Loh, Su Peng

2014-01-01

60

Preparation of Ag-M (M: Fe, Co and Mn)-ZSM-5 bimetal catalysts with high performance for catalytic oxidation of ethyl acetate.  

PubMed

The catalytic combustion of ethyl acetate has been investigated in a series of mono-metal silver and bimetal Ag-M (M: Fe, Co and Mn)-modified HZSM-5 zeolites. The objective was to find a catalyst with high superior activity, selectivity towards deep oxidation product and stability. The catalyst activity was measured under excess oxygen condition in a fixed bed reactor operated at gas hourly space velocity (GHSV) = 30000 h(-1), reaction temperature between 150 and 450 degrees C and ethyl acetate inlet concentration of 1000 ppm. Both Fe-Ag-ZSM-5 and Co-Ag-ZSM-5 catalysts exhibited high activity in the oxidation of ethyl acetate. The sequences of catalytic activity and catalytic stability were as follows: Fe-Ag-ZSM-5 > Co-Ag-ZSM-5 > Mn-Ag-ZSM-5 > Ag-ZSM-5 > HZSM-5. Total conversion of ethyl acetate was achieved at above 250 degrees C. The catalysts were characterized by inductively coupled plasma atomic emission spectroscopy, X-ray diffraction, transmission electron microscopy, scanning electron microscopy and X-ray photoelectron spectroscopy. PMID:21780707

Jodaei, A; Salari, D; Niaei, A; Khatamian, M; Caylak, N

2011-01-01

61

Mixture toxicity of SN2-reactive soft electrophiles: 3. Evaluation of ethyl ?-halogenated acetates with ?-halogenated acetonitriles.  

PubMed

Mixture toxicity for each of four ethyl ?-halogenated acetates with each of three ?-halogenated acetonitriles (xANs) was assessed. Inhibition of bioluminescence in Vibrio fischeri was measured after 15, 30, and 45 min of exposure. Concentration-response curves were developed for each chemical at each exposure duration and used to develop predicted concentration-response curves for the dose-addition and independence models of combined effect. Concentration-response curves for each mixture and each exposure duration were then evaluated against the predicted curves using three metrics per model: (1) EC50-based additivity quotient (AQ) or independence quotient (IQ) values; (2) mean AQ (mAQ) or mean IQ (mIQ) values, which were calculated by averaging the EC25, EC50, and EC75 AQ or IQ values; and (3) deviation values from additivity (DV-A) or independence (DV-I). Mixture toxicity for ethyl iodoacetate was dose-additive with each of the xANs at all exposure durations and was also often consistent with independence. The same was true for mixture toxicity of ethyl bromoacetate with each xAN. However, for the two more slowly reactive chemicals, ethyl chloroacetate (ECAC) and ethyl fluoroacetate (EFAC), mixture toxicity with each xAN only became consistent with dose-addition on increasing exposure duration. Consistency with independence for both ECAC and EFAC with the xANs was essentially limited to the EC50-IQ metric, thereby showing the utility of calculating the mean quotient (mAQ, mIQ) and deviation value (DV-A, DV-I) metrics. On review of these findings with those from the first two studies in the series, the results suggest that instances in which mixture toxicity was not consistent with dose-addition relate (1) to differences in the capability of the chemicals to form strong H-bonds with water; and (2) to differences in relative reactivity and time-dependent toxicity levels of the chemicals. PMID:24368709

Dawson, D A; Pöch, G; Schultz, T W

2014-02-01

62

Release Kinetic Studies of Aspirin Microcapsules from Ethyl Cellulose, Cellulose Acetate Phthalate and their Mixtures by Emulsion Solvent Evaporation Method  

PubMed Central

The present study was oriented towards microencapsulation of aspirin and the study of its release kinetics. The desired encapsulation was achieved by emulsion solvent evaporation method using ethyl cellulose (EC), cellulose acetate phthalate (CAP) and their mixture (1:1) of polymeric constituents. Characterization of the formulations was performed by size, shape, drug loading efficiency and in-vitro drug release analysis. The in-vitro release profiles from different polymeric microcapsules were applied on different kinetic models. The prepared microcapsules were found free flowing and almost spherical in shape with particle sizes ranging from 300–700?m, having a loading efficiency of 75–85%. The best fit model with the highest correlation coefficient was observed in Higuchi model, indicating diffusion controlled principle. The n value obtained from Korsemeyer-Peppas model varied between 0.5–0.7, confirming that the mechanism of drug release was diffusion controlled. Comparative studies revealed that the release of aspirin from EC microcapsules was slower as compared to that of CAP and their binary mixture. PMID:21179372

Dash, Vikas; Mishra, Sujeet K.; Singh, Manoj; Goyal, Amit K.; Rath, Goutam

2010-01-01

63

Leea indica Ethyl Acetate Fraction Induces Growth-Inhibitory Effect in Various Cancer Cell Lines and Apoptosis in Ca Ski Human Cervical Epidermoid Carcinoma Cells  

PubMed Central

The anticancer potential of Leea indica, a Chinese medicinal plant was investigated for the first time. The crude ethanol extract and fractions (ethyl acetate, hexane, and water) of Leea indica were evaluated their cytotoxicity on various cell lines (Ca Ski, MCF 7, MDA-MB-435, KB, HEP G2, WRL 68, and Vero) by MTT assay. Leea indica ethyl acetate fraction (LIEAF) was found showing the greatest cytotoxic effect against Ca Ski cervical cancer cells. Typical apoptotic morphological changes such as DNA fragmentation and chromatin condensation were observed in LIEAF-treated cells. Early signs of apoptosis such as externalization of phosphatidylserine and disruption of mitochondrial membrane potential indicated apoptosis induction. This was further substantiated by dose- and time-dependent accumulation of sub-G1 cells, depletion of intracellular glutathione, and activation of caspase-3. In conclusion, these results suggested that LIEAF inhibited cervical cancer cells growth by inducing apoptosis and could be developed as potential anticancer drugs. PMID:21423690

Yau Hsiung, Wong; Abdul Kadir, Habsah

2011-01-01

64

Ethyl 2-[1-(3-methyl­but­yl)-4-phenyl-1H-1,2,3-triazol-5-yl]-2-oxo­acetate  

PubMed Central

In the title compound, C17H21N3O3, the non-planar (r.m.s. deviation = 0.212?Å) ethyl (oxo)acetate group is oriented towards the phenyl substituent. The triazole and benzene rings are twisted with respect to each other, making a dihedral angle of 41.69?(6)°. In the crystal, mol­ecules are arranged into centrosymmetric R 2 2(10) dimers via pairs of C—H?O inter­actions involving the ethyl (oxo)acetate groups. In addition, the triazole rings show ?–? stacking inter­actions, with their centroids at a distance of 3.745?(2)?Å. PMID:24454217

Ahmed, Muhammad Naeem; Yasin, Khawaja Ansar; Tahir, M. Nawaz; Hafeez, Muhammad; Aziz, Shahid

2013-01-01

65

Prompt-NO formation in methane/oxygen/nitrogen flames seeded with oxygenated volatile organic compounds: Methyl ethyl ketone or ethyl acetate  

SciTech Connect

In the present work, CH and NO profiles are determined using laser-induced fluorescence (LIF) measurements in eight low-pressure laminar flames of CH{sub 4}/O{sub 2}/N{sub 2} containing various amounts of methyl ethyl ketone or ethyl acetate with respect to the equivalence ratio. Relative CH LIF signals are calibrated using cavity ring-down spectroscopy (CRDS), while NO LIF calibration is performed in the burned gases of NO seeded flames. Temperature measurements are obtained using a coated Pt/Rh thermocouple and serve as temperature profiles input for Chemkin modeling. Volatile organic compound (VOC) submechanisms, previously validated upon major and intermediate species profiles measured using sampling techniques, are incorporated into the GDF-Kin 3.0{sub N}CN for the CH{sub 4} oxidation. This mechanism is adjusted and validated to predict the effect of VOCs seeding on CH and NO formation. It takes into account not only the CH and NO profiles but those previously measured. When methane is replaced by either MEK or EA, the NO mole fraction in the burned gases and the CH peak value are found to jointly decrease, indicating that NO is mainly formed according to the prompt-NO mechanism. According to the kinetic analysis, the VOC impact on NO formation is demonstrated. It is shown that CH radical formation, through the C1 sequence, mainly involves the CH{sub 3} radical, which is formed with the same propensity by one molecule of methane, MEK, or EA. Due to the methane replacement by VOC while the equivalence ratio is maintained constant, we found that the CH peak value decrease follows the total fuel volumetric flow rate decrease, yielding, an NO decrease in the burned gases. (author)

Lamoureux, N.; El-Bakali, A.; Gasnot, L.; Pauwels, J.F.; Desgroux, P. [UMR CNRS 8522 PC2A ''Physicochimie des Processus de Combustion et de l'Atmosphere,'' Universite des Sciences et Technologies de Lille, 59655 Villeneuve d'Ascq Cedex (France)

2008-04-15

66

Comparison of Kato-Katz, ethyl-acetate sedimentation, and Midi Parasep® in the diagnosis of hookworm, Ascaris and Trichuris infections in the context of an evaluation of rural sanitation in India.  

PubMed

The Kato-Katz, conventional ethyl-acetate sedimentation, and Midi Parasep(®) methods for diagnosing infection with soil-transmitted helminths were compared. The Kato-Katz technique gave the best overall diagnostic performance with the highest results in all measures (prevalence, faecal egg count, sensitivity) followed by the conventional ethyl-acetate and then the Midi Parasep(®) technique. The Kato-Katz technique showed a significantly higher faecal egg count and sensitivity for both hookworm and Trichuris as compared to the Midi Parasep(®) technique. The conventional ethyl-acetate technique produced smaller pellets and showed lower pellet mobility as compared to the Midi Parasep(®). PMID:23467010

Funk, Anna L; Boisson, Sophie; Clasen, Thomas; Ensink, Jeroen H J

2013-06-01

67

Oxidation of ethyl acetate by a high performance nanostructure (Ni, Mn)-Ag/ZSM-5 bimetallic catalysts and development of an artificial neural networks predictive modeling.  

PubMed

The catalytic oxidation of ethyl acetate in low concentration was investigated over mono-metallic Ag/ZSM5 and bimetallic (Ni, Mn)-Ag/ZSM-5 catalysts. Catalytic studies were carried out in a catalytic fixed bed reactor under atmospheric pressure. The sequence of catalytic activity was as follows: Ni-Ag-ZSM-5 > Mn-Ag-ZSM-5 > Ag-ZSM-5 > H-ZSM-5. The catalysts were characterized by ICP-AES, X-ray diffraction (XRD), low temperature nitrogen adsorption, NH(3)-TPD, transmission electron microscopy (TEM), scanning electron microscopy (SEM) and diffuse reflectance UV-vis spectra (UV-vis). An artificial neural networks (ANN) model was developed to predict the performance of catalytic oxidation process over bimetallic Ni-Ag/ZSM-5 catalyst based on experimental data. For this purpose the standard feed forward back propagation algorithm was employed to train the model by using laboratory experimental data. A good agreement was resulted between experimental results and those obtained by ANN. Following order for variables effects on conversion yield of ethyl acetate was predicted by ANN model: reaction temperature (32.99%) > Ag loading (27.38%) > initial ethyl acetate concentration (23.58%) > Ni loading (16.05%). PMID:21104495

Jodaei, Azadeh; Salari, Darush; Niaei, Ali; Khatamian, Masumeh; Hosseini, Seyed Ali

2011-01-01

68

Modification and re-validation of the ethyl acetate-based multi-residue method for pesticides in produce  

PubMed Central

The ethyl acetate-based multi-residue method for determination of pesticide residues in produce has been modified for gas chromatographic (GC) analysis by implementation of dispersive solid-phase extraction (using primary–secondary amine and graphitized carbon black) and large-volume (20 ?L) injection. The same extract, before clean-up and after a change of solvent, was also analyzed by liquid chromatography with tandem mass spectrometry (LC–MS–MS). All aspects related to sample preparation were re-assessed with regard to ease and speed of the analysis. The principle of the extraction procedure (solvent, salt) was not changed, to avoid the possibility invalidating data acquired over past decades. The modifications were made with techniques currently commonly applied in routine laboratories, GC–MS and LC–MS–MS, in mind. The modified method enables processing (from homogenization until final extracts for both GC and LC) of 30 samples per eight hours per person. Limits of quantification (LOQs) of 0.01 mg kg?1 were achieved with both GC–MS (full-scan acquisition, 10 mg matrix equivalent injected) and LC–MS–MS (2 mg injected) for most of the pesticides. Validation data for 341 pesticides and degradation products are presented. A compilation of analytical quality-control data for pesticides routinely analyzed by GC–MS (135 compounds) and LC–MS–MS (136 compounds) in over 100 different matrices, obtained over a period of 15 months, are also presented and discussed. At the 0.05 mg kg?1 level acceptable recoveries were obtained for 93% (GC–MS) and 92% (LC–MS–MS) of pesticide–matrix combinations. PMID:17563885

Rooseboom, Astrid; van Dam, Ruud; Roding, Marleen; Arondeus, Karin; Sunarto, Suryati

2007-01-01

69

The Acetate Switch  

PubMed Central

To succeed, many cells must alternate between life-styles that permit rapid growth in the presence of abundant nutrients and ones that enhance survival in the absence of those nutrients. One such change in life-style, the “acetate switch,” occurs as cells deplete their environment of acetate-producing carbon sources and begin to rely on their ability to scavenge for acetate. This review explains why, when, and how cells excrete or dissimilate acetate. The central components of the “switch” (phosphotransacetylase [PTA], acetate kinase [ACK], and AMP-forming acetyl coenzyme A synthetase [AMP-ACS]) and the behavior of cells that lack these components are introduced. Acetyl phosphate (acetyl?P), the high-energy intermediate of acetate dissimilation, is discussed, and conditions that influence its intracellular concentration are described. Evidence is provided that acetyl?P influences cellular processes from organelle biogenesis to cell cycle regulation and from biofilm development to pathogenesis. The merits of each mechanism proposed to explain the interaction of acetyl?P with two-component signal transduction pathways are addressed. A short list of enzymes that generate acetyl?P by PTA-ACKA-independent mechanisms is introduced and discussed briefly. Attention is then directed to the mechanisms used by cells to “flip the switch,” the induction and activation of the acetate-scavenging AMP-ACS. First, evidence is presented that nucleoid proteins orchestrate a progression of distinct nucleoprotein complexes to ensure proper transcription of its gene. Next, the way in which cells regulate AMP-ACS activity through reversible acetylation is described. Finally, the “acetate switch” as it exists in selected eubacteria, archaea, and eukaryotes, including humans, is described. PMID:15755952

Wolfe, Alan J.

2005-01-01

70

The effect of culture liquid ethyl acetate mycelium extracts of medicinal mushrooms on the viability of human pancreatic cancer cells.  

PubMed

Pancreatic cancer, one of the deadliest of all solid malignancies, is one of the leading causes of cancer death worldwide, with 232,000 new cases and 213,000 deaths reported each year. These unfortunate statistics reflect the advanced stage at which most patients with pancreatic cancer are diagnosed and the paucity of effective chemotherapeutic regimens. Fungal metabolites have been gaining scientific interest because of their medicinal properties. In the present study, 31 different mushroom extracts of 12 medicinal mushroom species were screened for their effect on the viability of human pancreatic adenocarcinoma cells. Extraction procedures were executed with organic solvents--ethanol (EAL), ethyl acetate (EAC), and chloroform (CHL). In some cases, culture liquid (CL) extraction was also performed. All extracts were diluted to a concentration of 50 mg/mL dimethyl sulfoxide. Extract effects on cell viability were examined in human pancreatic adenocarcinoma cells HPAF-II (well differentiated) and PL5 (porrly differentiated), using XTT assay and crystal violet assay (CV). Furthermore, extract effects on LDH leakage were also studied in order to exclude necrotic damage of the extract. The screening phase revealed that among the total 31 extracts examined with various treatment doses (50-500 ?g/mL) administered for 72 h, the CL extract of the mushroom Cyathus striatus exhibited the most prominent decrease in cell viability. Moreover, exposure of cells to lower concentrations then the above (1, 2.5, 5, 7.5, 10, 15, 20, and 50 ?g/mL) for 24, 48, and 72 h showed a significant decrease in cell viability. Crystal violet results support these findings, and LDH levels measured suggest the lack of a necrotic effect of the extract. Our results indicate that C. striatus CL extract inhibits the viability of human pancreatic adenocarcinoma cells; HPAF-II and PL45. Growth inhibition can be achieved in low concentrations of the extract and a short exposure period. This effect can be mediated through apoptosis induction and/or cell cycle arrest; therefore, additional experiments are needed in order to elucidate the extract mechanism of action. These findings may lead to the development of new therapeutic strategies for the treatment of pancreatic cancer. PMID:22506577

Sharvit, Lital E; Wasser, Solomon P; Fares, Fuad

2012-01-01

71

Acidbase interaction in the acetic acid-acetic anhydride system  

Microsoft Academic Search

1.The electroconductivity and dielectric permeability of the acetic acid-acetic anhydride system have been measured. The electroconductivity of the system has a maximum close to 50% of the anhydride. The curve of the dielectric permeability is concave toward the composition axis.2.The dependence of the electroconductivity on the composition is explained by the formation of a complex between acetic acid and acetic

V. E. Bel'skii; M. I. Vinnik

1963-01-01

72

Synergistic effect of delignification and treatment with the ionic liquid 1-ethyl-3-methylimidazolium acetate on enzymatic digestibility of poplar wood.  

PubMed

This study examined the effects of removing key recalcitrance factors by ionic liquid (IL) treatment on the cellulase digestibility of poplar wood. Ground biomass was subjected to chlorite delignification and IL (1-ethyl-3-methylimidazolium acetate) treatment alone or in combination. The compositional and structural features of differentially treated biomass samples and their hydrolysis performance at various cellulase loadings were investigated. IL treatment caused minor compositional changes but drastically decreased cellulose crystallinity; in particular, when administered after delignification, an X-ray diffractogram similar to that of cellulose II polymorph was observed, suggesting that in the absence of lignin, the cellulose was dissolved in the IL and regenerated in water with a polymorphic transformation. The structural changes induced by the combined delignification-IL treatment facilitated the enzymatic hydrolysis of cellulose; the biomass could be fully degraded within 72 h by 4 FPU of cellulase per gram glucan, with cellobiose degradation being the rate-limiting step. PMID:24755318

Wu, Long; Kumagai, Akio; Lee, Seung-Hwan; Endo, Takashi

2014-06-01

73

Vapor pressure of ethyl (5-cyano-3,4-diphenyl-6-oxo-1,6-dihydropyridazin-1-yl)acetate by the effusion method  

SciTech Connect

The effusion method was used to determine the vapor pressure of ethyl (5-cyano-3,4-diphenyl-6-oxo-1,6-dihydropyridazin-1-yl)acetate (I) at 13 temperatures, in the range 123-141 /sup 0/C, with a minimum of two results at each temperature. Measured vapor pressures were in the range 10/sup -4/-6 X 10/sup -4/ torr and were expressed by the following equation: log p = 13.40 - (689 1/T), where p is the vapor pressure in torr and T is the absolute temperature. The 95% confidence limits for the constants of the equation are respectively + or - 1.19 and + or - 486. Experimental conditions studied included effusion hole diameter and effusion time. This compound undergoes no phase change below the melting point (about 143 /sup 0/C). All the results are for the crystalline phase below 143 /sup 0/C. Some results by the gas saturation procedure are also included.

DePablo, R.S.

1982-10-01

74

Bis[3?,7?,12?-tris-(4-nitro-benzo-yloxy)-5?-cholan-24-yl] disulfide-ethyl acetate-n-hexane (4/4/1)  

PubMed Central

The crystal structure of the title compound, C90H100N6O24S2·C4H8O2·0.25C6H14, solved and refined against synchrotron diffraction data, contains two formula units in the asymmetric unit with the all-trans n-hexane mol­ecule having half-occupancy and one of the ethyl acetate mol­ecules disordered over two positions. The two symmetry-independent disulfide mol­ecules are assembled by approximate face-to-face and face-to-edge inter­actions between their 4-nitro­benzo­yloxy groups into an inter­twined dimer having a double-helix-type structure. The centrally placed disulfide bridges in the two symmetry-independent mol­ecules exhibit different helicity as shown by the C—S—S—C torsion angles of 71.0?(1) and ?92.5?(1)°. PMID:21522786

Brzezinski, Krzysztof; Tomkiel, Aneta M.; Lotowski, Zenon; Morzycki, Jacek; Dauter, Zbigniew

2011-01-01

75

Acetic Acid Catalyzed Carbon Aerogels  

Microsoft Academic Search

We prepared carbon aerogels with a wide range of structural properties and densities using the weak acetic acid as a catalyst. Two series of acetic acid catalyzed carbon aerogels with different dilution of the catalyst and the monomers were investigated accurately. Structural investigation was performed via (U)SAXS, gas sorption and SEM. The pore and particle size can be tailored according

R. Brandt; R. Petricevic; H. Pröbstle; J. Fricke

2003-01-01

76

Acetate metabolism in Methanothrix soehngenii  

Microsoft Academic Search

Acetate is quantitatively the most important intermediate in the anaerobic degradation of soluble organic matter. The conversion rate of acetate by methanogenic bacteria is proposed to be the rate limiting step in this degradation The study of acetoclastic methanogens, therefore is of relevance to our understanding of anaerobic processes and their optimal application in treatment of waste water from various

M. S. M. Jetten

1991-01-01

77

Acetic acid bacteria in oenology  

Microsoft Academic Search

Acetic acid bacteria have always been considered the bad mi- croorganisms of oenology; responsible for wine spoiling (vine- gary taint). The taxonomy and our knowledge of the metabo- lism of acetic acid bacteria are rapidly evolving, especially as new molecular biology techniques are applied to this fastidious group of microorganisms, which are still rather difficult to work with. The dramatic

A. Mas; M. J. Torija; A. González; M. Poblet; J. M. Guillamón

78

Molecular Structure of Phenylmercuric acetate  

NSDL National Science Digital Library

Phenylmercuric acetate is white to white-yellow crystalline powder that is odorless. This phenyl mercury compound is used mainly as a fungicide, herbicide, slimicide and bacteriocide. Phenylmercuric acid serves as a preservative in canned paint, eye ointments and drops, injectable solutions, skin disinfectants and in cosmetics products such as hair shampoos, mouthwashes and toothpastes. It is also used in contraceptive gels and foams. Phenylmercuric acetate is prepared by interaction of benzene with mercuric acetate in glacial acetic acid. Phenylmercuric acetate's former production and use as a fungicide and as a mildew inhibitor in paints may have resulted in its direct release to the environment. This substance is very toxic to aquatic organisms and may be hazardous to the environment.

2004-11-10

79

Conductance of Dilute Sodium Acetate Solutions to 469 K and of Acetic Acid and Sodium Acetate\\/Acetic Acid Mixtures to 548 K and 20 MPa  

Microsoft Academic Search

In order to obtain accurate association constants for sodium acetate, a very precise flow method was used to measure the electrical conductivity of dilute aqueous solutions of sodium acetate at ambient conditions and 469 K and 20 MPa. Measurements at ambient conditions, 469 and 548 K and 20 MPa, were also made on sodium acetate\\/acetic acid mixtures and acetic acid.

G. H. Zimmerman; R. H. Wood

2002-01-01

80

Isolation and Bioactivity Analysis of Ethyl Acetate Extract from Acer tegmentosum Using In Vitro Assay and On-Line Screening HPLC-ABTS+ System  

PubMed Central

The Acer tegmentosum (3?kg) was extracted using hot water, and the freeze-dried extract powder was partitioned successively using dichloromethane (DCM), ethyl acetate (EA), butyl alcohol (n-BuOH), and water. From the EA extract fraction (1.24?g), five phenolic compounds were isolated by the silica gel, octadecyl silica gel, and Sephadex LH-20 column chromatography. Based on spectroscopic methods such as 1H-NMR, 13C-NMR, and LC/MS the chemical structures of the compounds were confirmed as feniculin (1), avicularin (2), (+)-catechin (3), (?)-epicatechin (4), and 6?-O-galloyl salidroside (5). Moreover, a rapid on-line screening HPLC-ABTS+ system for individual bioactivity of the EA-soluble fraction (five phenolic compounds) was developed. The results indicated that compounds 1 and 2 were first isolated from the A. tegmentosum. The anti-inflammatory activities and on-line screening HPLC-ABTS+ assay method of these compounds in LPS-stimulated murine macrophages were rapid and efficient for the investigation of bioactivity of A. tegmentosum. PMID:25386382

Song, Na-Young; Oh, You Chang; Cho, Won-Kyung; Ma, Jin Yeul

2014-01-01

81

In Vivo Antioxidant and Anti-Skin-Aging Activities of Ethyl Acetate Extraction from Idesia polycarpa Defatted Fruit Residue in Aging Mice Induced by D-Galactose  

PubMed Central

Two different concentrations of D-galactose (D-gal) induced organism and skin aging in Kunming mice were used to examine comprehensively the antioxidant and antiaging activities of ethyl acetate extraction (EAE) from Idesia polycarpa defatted fruit residue for the first time. The oxygen radical absorbance capacity (ORAC) of EAE was 13.09 ± 0.11??mol Trolox equivalents (TE)/mg, which showed EAE had great in vitro free radical scavenging and antioxidant activity. Biochemical indexes and morphological analysis of all tested tissues showed that EAE could effectively improve the total antioxidant capacity (T-AOC) of the antioxidant defense system of the aging mice, enhance the activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) of tissues and serum, increase glutathione (GSH) content and decrease the malondialdehyde (MDA) content, and maintain the skin collagen, elastin, and moisture content. Meanwhile, EAE could effectively attenuate the morphological damage in brain, liver, kidney, and skin induced by D-gal and its effect was not less than that of the well-known L-ascorbic acid (VC) and ?-tocopherol (VE). Overall, EAE is a potent natural antiaging agent with great antioxidant activity, which can be developed as a new medicine and cosmetic for the treatment of age-related conditions. PMID:24971146

Jia, Ran-ran; Chen, Fang

2014-01-01

82

In Vivo Antioxidant and Anti-Skin-Aging Activities of Ethyl Acetate Extraction from Idesia polycarpa Defatted Fruit Residue in Aging Mice Induced by D-Galactose.  

PubMed

Two different concentrations of D-galactose (D-gal) induced organism and skin aging in Kunming mice were used to examine comprehensively the antioxidant and antiaging activities of ethyl acetate extraction (EAE) from Idesia polycarpa defatted fruit residue for the first time. The oxygen radical absorbance capacity (ORAC) of EAE was 13.09 ± 0.11? ? mol Trolox equivalents (TE)/mg, which showed EAE had great in vitro free radical scavenging and antioxidant activity. Biochemical indexes and morphological analysis of all tested tissues showed that EAE could effectively improve the total antioxidant capacity (T-AOC) of the antioxidant defense system of the aging mice, enhance the activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) of tissues and serum, increase glutathione (GSH) content and decrease the malondialdehyde (MDA) content, and maintain the skin collagen, elastin, and moisture content. Meanwhile, EAE could effectively attenuate the morphological damage in brain, liver, kidney, and skin induced by D-gal and its effect was not less than that of the well-known L-ascorbic acid (VC) and ? -tocopherol (VE). Overall, EAE is a potent natural antiaging agent with great antioxidant activity, which can be developed as a new medicine and cosmetic for the treatment of age-related conditions. PMID:24971146

Ye, Yang; Jia, Ran-Ran; Tang, Lin; Chen, Fang

2014-01-01

83

Crystal structure of ethyl 2-(di-eth-oxy-phosphor-yl)-2-(2,3,4-tri-meth-oxy-phen-yl)acetate.  

PubMed

The title compound, C17H27O8P, was prepared by Michaelis-Arbuzov reaction of ethyl 2-bromo-2-(2,3,4-tri-meth-oxy-phen-yl)acetate and triethyl phosphite. Such compounds rarely crystallize, but single crystals were recovered after the initial oil was left for approximately 10 years. The bond angle of the sp (3)-hybridized C atom connecting the benzene derivative with the phospho unit is widened marginally [112.5?(2)°]. The terminal P-O bond length of 1.464?(2)?Å clearly indicates a double bond, whereas the two O atoms of the eth-oxy groups connected to the phospho-rous atom have bond lengths of 1.580?(2)?Å and 1.581?(3)?Å. The three meth-oxy groups emerge out of the benzene-ring plane due to steric hindrance [C-C-O-C torsion angles = -179.9?(3)°, -52.9?(4)° and 115.3?(4)°]. In the crystal, inversion dimers linked by pairs of C-H?O=P hydrogen bonds generate R 2 (2)(14) loops. The chosen crystal was modelled as a non-merohedral twin. PMID:25309241

Schubert, Moritz; Schollmeyer, Dieter; Waldvogel, Siegfried R

2014-09-01

84

Crystal structure of ethyl 2-(di-eth-oxy-phosphor-yl)-2-(2,3,4-tri-meth-oxy-phen-yl)acetate  

PubMed Central

The title compound, C17H27O8P, was prepared by Michaelis–Arbuzov reaction of ethyl 2-bromo-2-(2,3,4-tri­meth­oxy­phen­yl)acetate and triethyl phosphite. Such compounds rarely crystallize, but single crystals were recovered after the initial oil was left for approximately 10 years. The bond angle of the sp 3-hybridized C atom connecting the benzene derivative with the phospho unit is widened marginally [112.5?(2)°]. The terminal P—O bond length of 1.464?(2)?Å clearly indicates a double bond, whereas the two O atoms of the eth­oxy groups connected to the phospho­rous atom have bond lengths of 1.580?(2)?Å and 1.581?(3)?Å. The three meth­oxy groups emerge out of the benzene-ring plane due to steric hindrance [C—C—O—C torsion angles = ?179.9?(3)°, ?52.9?(4)° and 115.3?(4)°]. In the crystal, inversion dimers linked by pairs of C—H?O=P hydrogen bonds generate R 2 2(14) loops. The chosen crystal was modelled as a non-merohedral twin. PMID:25309241

Schubert, Moritz; Schollmeyer, Dieter; Waldvogel, Siegfried R.

2014-01-01

85

Autophagic Cell Death Is Induced by Acetone and Ethyl Acetate Extracts from Eupatorium odoratum In Vitro: Effects on MCF-7 and Vero Cell Lines  

PubMed Central

Eupatorium odoratum (EO) contains many biologically active compounds, the anticancer effects of which are not well documented. This study evaluates the cytotoxic effects and mechanism of action of EO extracts on MCF-7 and Vero cell lines. Evaluation of the cytotoxic activity using MTT assay, morphological alterations, and apoptosis were carried out. Autophagy was evaluated by LC3-A protein expression. Cytotoxic activity, membrane blebbing and ballooning at 24 hours, replacement by mass vacuolation, and double membrane vesicles mimicking autophagy and cell death were observed in the cancer cells. No apoptosis was observed by DNA fragmentation assay. Overexpression of LC3-A protein indicated autophagic cell death. Cell cycle analysis showed G0 and G2/M arrest. The Vero cells did not show significant cell death at concentrations <100??g/mL. These results thus suggest that acetone and ethyl acetate extracts of EO induce cell death through induction of autophagy and hold potential for development as potential anticancer drugs. PMID:22666123

Harun, Faizah Bt.; Syed Sahil Jamalullail, Syed Mohsin; Yin, Khoo Boon; Othman, Zulkhairi; Tilwari, Anita; Balaram, Prabha

2012-01-01

86

Ethyl acetate extract from Jiedu Xiaozheng Yin inhibits the proliferation of human hepatocellular carcinoma cells by suppressing polycomb gene product Bmi1 and Wnt/?-catenin signaling.  

PubMed

Jiedu Xiaozheng Yin (JXY) is a Chinese herbal decoction used to treat hepatocellular carcinoma (HCC). Previous studies have demonstrated that JXY can inhibit HCC cell proliferation via induction of G0/G1 phase arrest. In this study, we investigated whether the inhibitory effect of JXY on HCC cells is associated with the inhibition of the Wnt/??catenin pathway and the polycomb gene product Bmi1. Ethyl acetate extract from JXY (EE-JXY) was prepared. Methyl thiazolyl tetrazolium (MTT) and colony formation assays were used to measure cell proliferation. Immunofluorescence was used to analyze the expression and location of ?-catenin and Bmi1. Immunohistochemistry was used to examine the expression of proliferating cell nuclear antigen (PCNA), c-myc and cyclin D1. ?-catenin, Bmi1, c-myc, cyclin D1 and p16INK4A mRNA levels were detected by RT-PCR. The results demonstrated that EE-JXY inhibited the expression of PCNA, c-myc, cyclin D1 and Bmi1, and upregulated the expression of p16INK4A. We also found that EE-JXY could facilitate ?-catenin translocation from the cytoplasm and nuclei to the cytomembrane. Finally, suppression of cell proliferation and expression of Bmi1 and Wnt/?-catenin by EE-JXY was confirmed in a mouse xenograft model of HCC. Thus, EE-JXY can inhibit the proliferation of HCC partially via suppression of the Bmi1 and Wnt/?-catenin signaling pathways. PMID:25333742

Chen, Xu-Zheng; Cao, Zhi-Yun; Li, Jin-Nong; Hu, Hai-Xia; Zhang, You-Quan; Huang, Yun-Mei; Liu, Zhi-Zhen; Hu, Dan; Liao, Lian-Ming; Du, Jian

2014-12-01

87

Standardized ethyl acetate fraction from the roots of Brassica rapa attenuates the experimental arthritis by down regulating inflammatory responses and inhibiting NF-?B activation.  

PubMed

This study was undertaken to investigate the anti-arthritic potential of a standardized ethyl acetate fraction from the roots of Brassica rapa (EABR) and to explore the molecular mechanisms in adjuvant-induced arthritic rats and macrophages. In AIA-induced arthritic rats, EABR significantly reduced paw swelling, an arthritic index, serum rheumatoid factor, and tissue expression ratio of RANKL/OPG versus vehicle-administered group. This was found to be well correlated with significant suppressions in productions of PGE2, NO, and pro-inflammatory cytokines and in activations of NF-?B in AIA-induced paw tissues and LPS-induced macrophages. EABR attenuated NF-?B activation by reducing the nuclear translocation and phosphorylation of the p65 NF-?B, which were accompanied by parallel reductions in the degradation and phosphorylation of I?B? after blocking the phosphorylation mediated IKK activation. The findings suggest EABR exerts its anti-arthritic and anti-inflammatory properties via NF-?B inactivation in vitro and in vivo, and that EABR is a potential therapeutic for the treatment of arthritis and inflammation-associated disorders. PMID:24468670

Shin, Ji-Sun; Yun, Chang Hyeon; Chung, Kyung-Sook; Bang, Myun-Ho; Baek, Nam-In; Chung, Hae-Gon; Cho, Young-Wuk; Lee, Kyung-Tae

2014-04-01

88

Electrically generated lead(IV) acetate and manganese(III) acetate as reagents for coulometric redox titrations in acetic acid  

Microsoft Academic Search

Summary The conditions were investigated for electrochemical generation of lead(IV) acetate in acetic acid by oxidation of lead(II) acetate on a lead dioxide electrode and on a platinum electrode. Bivalent manganese ions are quantitatively oxidized on a platinum electrode to the tervalent state in the same solvent. Coulometric titration methods for the determination of small amounts of hydroquinone in acetic

Tibor J. Pastor; Vilim J. Vajgand; Zorica Kicovic

1976-01-01

89

Baicalein, Ethyl Acetate, and Chloroform Extracts of Scutellaria baicalensis Inhibit the Neuraminidase Activity of Pandemic 2009 H1N1 and Seasonal Influenza A Viruses  

PubMed Central

This study rated antiviral activity of Scutellaria baicalensis Georgi (S. baicalensis) extracts against influenza A virus subtypes, for example, pandemic 2009 H1N1, seasonal H1N1 and H3N2. Ethyl acetate (EtOAc) and chloroform extracts inhibited in vitro neuraminidase (NA) enzymatic activity and viral replication more than methanol (MeOH) extract. EtOAc extract demonstrated NA inhibition IC50 values ranging from 73.16 to 487.40??g/mL and plaque reduction IC50 values ranging from 23.7 to 27.4??g/mL. Chloroform extract showed antiviral activities with plaque reduction IC50 values ranging from 14.16 to 41.49??g/mL Time-of-addition assay indicated that EtOAc and chloroform extracts also significantly inhibited virus yields after infection. HPLC analysis demonstrated that baicalin was dominant in the MeOH extract; baicalein and chrysin were rich in the EtOAc and chloroform extracts. Molecular simulation revealed baicalein hydrogen bonding with Glu277 as well as hydrophobic and Van der Waals interactions with Ile222, Arg224, Ser246, and Tyr347 in NA1 active sites of NA1. Baicalein inhibited in vitro replication of influenza A viruses pandemic 2009 H1N1 (IC50?=?0.018??M) and seasonal 2007 H1N1 using plaque reduction assays. A combination of low-dose baicalein with other anti-influenza agents could be applicable for development of alternative remedies treating influenza A virus infection. PMID:23864896

Hour, Mann-Jen; Huang, Su-Hua; Chang, Ching-Yao; Lin, Yen-Kuan; Wang, Ching-Ying; Chang, Yuan-Shiun

2013-01-01

90

Correlation between acetic acid resistance and characteristics of PQQ-dependent ADH in acetic acid bacteria  

Microsoft Academic Search

In this study, we compared the growth properties and molecular characteristics of pyrroloquinoline quinone (PQQ)-dependent alcohol dehydrogenase (ADH) among highly acetic acid-resistant strains of acetic acid bacteria. Ga. europaeus exhibited the highest resistance to acetic acid (10%), whereas Ga. intermedius and Acetobacter pasteurianus resisted up to 6% of acetic acid. In media with different concentrations of acetic acid, the maximal

Janja Trcek; Hirohide Toyama; Jerzy Czuba; Anna Misiewicz; Kazunobu Matsushita

2006-01-01

91

Regeneration of Cellulose Acetate Membranes.  

National Technical Information Service (NTIS)

Several simple methods for in situ one-step regeneration of both flux and salt-retention properties of service-deteriorated membranes have been developed. Membranes have been successfully regenerated using hot, 4% acetic acid, and a one-step cleaning meth...

P. A. Cantor, W. S. Higley, C. W. Saltonstall

1970-01-01

92

21 CFR 184.1721 - Sodium acetate.  

Code of Federal Regulations, 2013 CFR

...anhydrous or trihydrated form. It is produced synthetically by the neutralization of acetic acid with sodium carbonate or by treating calcium acetate with sodium sulfate and sodium bicarbonate. (b) The ingredient meets the...

2013-04-01

93

21 CFR 184.1721 - Sodium acetate.  

...anhydrous or trihydrated form. It is produced synthetically by the neutralization of acetic acid with sodium carbonate or by treating calcium acetate with sodium sulfate and sodium bicarbonate. (b) The ingredient meets the...

2014-04-01

94

21 CFR 184.1721 - Sodium acetate.  

Code of Federal Regulations, 2012 CFR

...anhydrous or trihydrated form. It is produced synthetically by the neutralization of acetic acid with sodium carbonate or by treating calcium acetate with sodium sulfate and sodium bicarbonate. (b) The ingredient meets the...

2012-04-01

95

21 CFR 184.1721 - Sodium acetate.  

Code of Federal Regulations, 2011 CFR

...anhydrous or trihydrated form. It is produced synthetically by the neutralization of acetic acid with sodium carbonate or by treating calcium acetate with sodium sulfate and sodium bicarbonate. (b) The ingredient meets the...

2011-04-01

96

21 CFR 184.1721 - Sodium acetate.  

Code of Federal Regulations, 2010 CFR

...anhydrous or trihydrated form. It is produced synthetically by the neutralization of acetic acid with sodium carbonate or by treating calcium acetate with sodium sulfate and sodium bicarbonate. (b) The ingredient meets the...

2010-04-01

97

Concentrating aqueous acetate solutions with tertiary amines  

E-print Network

Water may be extracted from aqueous calcium acetate or sodium acetate solutions using low miscibility, low molecular weight tertiary amines, e.g. triethylamine (TEA) and N,N- dietliylmethylaniine (DEMA). This novel extraction technology...

Lee, Champion

2012-06-07

98

Anti-inflammatory and analgesic activities of newly synthesized chiral peptide derivatives using (3-benzoyl- 4,5-dioxo-2-phenyl-pyrrolidin-1-yl)acetic acid ethyl ester as starting material.  

PubMed

A series of heterocyclic derivatives was synthesized using (3-benzoyl-4,5-dioxo-2-phenyl-pyrrolidin-1-yl)acetic acid ethyl ester 1 as starting material. Treatment of 1 with 1 N NaOH or hydrazine hydrate afford the corresponding acid 2 and acid hydrazides 4 and 5, which were reacted with several reagents to produce some new peptido hetero-organic derivatives 6-12. The pharmacological screening showed that many of these newly synthesized compounds have good anti-inflammatory and analgesic activities comparable to diclofenac potassium and valdecoxib as reference drugs. PMID:18214842

Fakhr, Issa M; Amr, Abdel-Galil E; Sabry, Nermien M; Abdalah, Mohamed M

2008-03-01

99

Anodically generated cobalt(III) acetate as reagent for coulometric titrations in acetic acid  

Microsoft Academic Search

Summary Conditions for the anodic generation of cobalt(III) acetate with high current efficiency in non-aqueous solutions of potassium acetate in acetic acid have been investigated. The presence of water or acetic anhydride in the anolyte diminishes the amount of the generated oxidant. The stability of the generated cobalt(III) acetate solution is decreased in the presence of water and at elevated

T. J. Pastor; I. ?iri?

1985-01-01

100

Metabolism of steroid acetates by Streptomyces albus.  

PubMed

Fermentation of 16-dehydropregnenolone acetate (1a) with Streptomyces albus yielded 16-dehydropregnenolone (1b) and 16-dehydroprogesterone (IIa). Similar incubation of pregnenolone acetate (Ic) with the strain afforded pregnenolone (Id), progesterone (IIb) and 20 alpha-hydroxy progesterone (IIc) while dehydroepiandrosterone acetate (IIIa) under the conditions was converted to dehydroepiandrosterone (IIIb), androstenedione (IVa) and testosterone (IVc). The strain was also capable of converting testosterone acetate (IVb) having the 17-acetoxy function in the 5-membered D-ring to testosterone (IVc) and androstenedione (IVa). All the products were identified by the application of various chemical and spectrometric techniques. PMID:6708550

Mukherjee, A; Mahato, S B

1984-03-01

101

Ethyl acetate extract of germinated brown rice attenuates hydrogen peroxide-induced oxidative stress in human SH-SY5Y neuroblastoma cells: role of anti-apoptotic, pro-survival and antioxidant genes  

PubMed Central

Background There are reports of improved metabolic outcomes due to consumption of germinated brown rice (GBR). Many of the functional effects of GBR can be linked to its high amounts of antioxidants. Interestingly, dietary components with high antioxidants have shown promise in the prevention of neurodegenerative diseases like Alzheimer’s disease (AD). This effect of dietary components is mostly based on their ability to prevent apoptosis, which is believed to link oxidative damage to pathological changes in AD. In view of the rich antioxidant content of GBR, we studied its potential to modulate processes leading up to AD. Methods The total phenolic content and antioxidant capacity of the ethyl acetate extract of GBR were compared to that of brown rice (BR), and the cytotoxicity of both extracts were determined on human SH-SY5Y neuronal cells using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) Assay. Based on its higher antioxidant potentials, the effect of the GBR extract on morphological changes due to hydrogen peroxide (H2O2)-induced oxidative damage in human SH-SY5Y neuronal cells was examined using inverted light microscope and fluorescence microscope by means of acridine orange-propidium iodide (AO/PI) staining. Also, evaluation of the transcriptional regulation of antioxidant and apoptotic genes was carried out using Multiplex Gene Expression System. Results The ethyl acetate extract of GBR had higher total phenolic content and antioxidant capacity compared to BR. The cytotoxicity results showed that GBR extract did not cause any damage to the human SH-SY5Y neuronal cells at concentrations of up to 20 ppm, and the morphological analyses showed that the GBR extract (up to 10 ppm) prevented H2O2-induced apoptotic changes in the cells. Furthermore, multiplex gene expression analyses showed that the protection of the cells by the GBR extract was linked to its ability to induce transcriptional changes in antioxidant (SOD 1, SOD 2 and catalase) and apoptotic (AKT, NF-K?, ERK1/2, JNK, p53 and p38 MAPK) genes that tended towards survival. Conclusions Taken together, the results of our study showed that the ethyl acetate extract of GBR, with high antioxidant potentials, could prevent H2O2-induced oxidative damage in SH-SY5Y cells. The potential of GBR and its neuroprotective mechanism in ameliorating oxidative stress-related cytotoxicity is therefore worth exploring further. PMID:23866310

2013-01-01

102

Positron scattering from vinyl acetate  

NASA Astrophysics Data System (ADS)

Using a Beer-Lambert attenuation approach, we report measured total cross sections (TCSs) for positron scattering from vinyl acetate (C4H6O2) in the incident positron energy range 0.15-50 eV. In addition, we also report an independent atom model with screening corrected additivity rule computation results for the TCSs, differential and integral elastic cross sections, the positronium formation cross section and inelastic integral cross sections. The energy range of these calculations is 1-1000 eV. While there is a reasonable qualitative correspondence between measurement and calculation for the TCSs, in terms of the energy dependence of those cross sections, the theory was found to be a factor of ˜2 larger in magnitude at the lower energies, even after the measured data were corrected for the forward angle scattering effect.

Chiari, L.; Zecca, A.; Blanco, F.; García, G.; Brunger, M. J.

2014-09-01

103

Oxygen17 and proton nuclear magnetic resonance studies on acetic acid exchange processes of the chloride, nitrate, and acetate of nickel(II) in acetic acid  

Microsoft Academic Search

The exchange rates of acetic acid coordinating to nickel(II) chloride, nickel(II) nitrate, and nickel(II) acetate in neat acetic acid and acetic acid\\/dichloromethane-d2 mixtures were measured by the oxygen-17 and proton NMR line-broadening methods. The activation parameters for the acetic acid exchange on these nickel(II) salts were independent of the concentration of acetic acid (HOAc) in the mixed solvents. The first-order

A. Hioki; S. Funahashi; M. Tanaka

1985-01-01

104

Anti-inflammatory potential of an ethyl acetate fraction isolated from Justicia gendarussa roots through inhibition of iNOS and COX-2 expression via NF-?B pathway.  

PubMed

Justicia gendarussa Burm.f. (J. gendarussa) is a plant used as traditional medicine in different parts of India and China to treat inflammatory disorders like rheumatoid arthritis. But its mechanism of anti-inflammatory action is still unclear. Hence in this context, the objective of our study is to reveal the mechanism of anti-inflammatory activity of J. gendarussa which would form an additional proof to the traditional knowledge of this plant. The anti-inflammatory function and mechanism(s) of action was studied in an ethyl acetate fraction isolated from methanolic extract of J. gendarussa roots (EJG). Anti-inflammatory studies were conducted on rats using partitioned fractions isolated from methanolic extract of J. gendarussa roots. In carrageenan-induced rat paw edema, ethyl acetate fraction brought about 80% and 93% edema inhibition at 3rd and 5th hour at a dose of 50 mg/kg, when compared to other extracts and Voveran. We investigated whether EJG inhibits the release of cycloxygenase (COX), 5-lipoxygenase (5-LOX), interleukin-6 (IL-6) and nuclear factor kappa B (NF-?B) in LPS stimulated human peripheral blood mononuclear cells (hPBMCs). Results shows that EJG dose dependently inhibited LPS-activated COX, 5-LOX, IL-6, and NF-?B in hPBMCs. EJG also reduced LPS induced levels of iNOS and COX-2 mRNA expression in hPBMCs. This study provides an insight into the probable mechanism(s) underlying the anti-inflammatory activity of EJG and therefore, we report the first confirmation of the anti-inflammatory potential of this traditionally employed herbal medicine in vitro. PMID:22063737

Kumar, Kavitha S; Vijayan, Viji; Bhaskar, Shobha; Krishnan, Kripa; Shalini, V; Helen, A

2012-01-01

105

Biodegradable Plastics Based on Cellulose Acetate  

Microsoft Academic Search

It is generally known that secondary cellulose acetate (with 53 to 56% acetyl groups) is suitable for thermoplastic processing. With appropriate plasticizers a plastic material is obtained which excels in transparency and pleasant texture, and it is therefore often used for tool handles, combs, spectacle frames, and the like. In principle, cellulose acetate with such a degree of substitution is

Alexander Ach

1993-01-01

106

21 CFR 582.1005 - Acetic acid.  

Code of Federal Regulations, 2012 CFR

21 Food and Drugs 6 2012-04-01...2012-04-01 false Acetic acid. 582.1005 Section 582.1005 Food and Drugs FOOD AND DRUG ADMINISTRATION...CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED... § 582.1005 Acetic acid. (a) Product....

2012-04-01

107

21 CFR 582.1005 - Acetic acid.  

Code of Federal Regulations, 2013 CFR

21 Food and Drugs 6 2013-04-01...2013-04-01 false Acetic acid. 582.1005 Section 582.1005 Food and Drugs FOOD AND DRUG ADMINISTRATION...CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED... § 582.1005 Acetic acid. (a) Product....

2013-04-01

108

21 CFR 582.1005 - Acetic acid.  

Code of Federal Regulations, 2011 CFR

21 Food and Drugs 6 2011-04-01...2011-04-01 false Acetic acid. 582.1005 Section 582.1005 Food and Drugs FOOD AND DRUG ADMINISTRATION...CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED... § 582.1005 Acetic acid. (a) Product....

2011-04-01

109

21 CFR 582.1005 - Acetic acid.  

Code of Federal Regulations, 2010 CFR

21 Food and Drugs 6 2010-04-01...2010-04-01 false Acetic acid. 582.1005 Section 582.1005 Food and Drugs FOOD AND DRUG ADMINISTRATION...CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED... § 582.1005 Acetic acid. (a) Product....

2010-04-01

110

21 CFR 582.1005 - Acetic acid.  

21 Food and Drugs 6 2014-04-01...2014-04-01 false Acetic acid. 582.1005 Section 582.1005 Food and Drugs FOOD AND DRUG ADMINISTRATION...CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED... § 582.1005 Acetic acid. (a) Product....

2014-04-01

111

Ionothermal Synthesis of Homochiral Framework with Acetate Pillared Cobalt-Camphorate Architecture  

PubMed Central

A new organically templated homochiral material (EMIm)[Co2(d-cam)2(ac)] (1, d-H2cam = d-camphoric acid; ac = acetate; EMIm = 1-ethyl-3-methylimidazolium) has been ionothermally synthesized and it features an unusual acetate pillared cobalt-camphorate architecture encapsulating the cationic component of ionic liquid. PMID:18537237

Chen, Shumei; Zhang, Jian; Bu, Xianhui

2009-01-01

112

Correlation between acetic acid resistance and characteristics of PQQ-dependent ADH in acetic acid bacteria.  

PubMed

In this study, we compared the growth properties and molecular characteristics of pyrroloquinoline quinone (PQQ)-dependent alcohol dehydrogenase (ADH) among highly acetic acid-resistant strains of acetic acid bacteria. Gluconacetobacter europaeus exhibited the highest resistance to acetic acid (10%), whereas Gluconacetobacter intermedius and Acetobacter pasteurianus resisted up to 6% of acetic acid. In media with different concentrations of acetic acid, the maximal acetic acid production rate of Ga. europaeus slowly increased, but specific growth rates decreased concomitant with increased concentration of acetic acid in medium. The lag phase of A. pasteurianus was twice and four times longer in comparison to the lag phases of Ga. europaeus and Ga. intermedius, respectively. PQQ-dependent ADH activity was twice as high in Ga. europaeus and Ga. intermedius as in A. pasteurinus. The purified enzymes showed almost the same specific activity to each other, but in the presence of acetic acid, the enzyme activity decreased faster in A. pasteurianus and Ga. intermedius than in Ga. europaeus. These results suggest that high ADH activity in the Ga. europaeus cells and high acetic acid stability of the purified enzyme represent two of the unique features that enable this species to grow and stay metabolically active at extremely high concentrations of acetic acid. PMID:16133326

Trcek, Janja; Toyama, Hirohide; Czuba, Jerzy; Misiewicz, Anna; Matsushita, Kazunobu

2006-04-01

113

Acetic acid fermentation of acetobacter pasteurianus: relationship between acetic acid resistance and pellicle polysaccharide formation.  

PubMed

Acetobacter pasteurianus strains IFO3283, SKU1108, and MSU10 were grown under acetic acid fermentation conditions, and their growth behavior was examined together with their capacity for acetic acid resistance and pellicle formation. In the fermentation process, the cells became aggregated and covered by amorphous materials in the late-log and stationary phases, but dispersed again in the second growth phase (due to overoxidation). The morphological change in the cells was accompanied by changes in sugar contents, which might be related to pellicle polysaccharide formation. To determine the relationship between pellicle formation and acetic acid resistance, a pellicle-forming R strain and a non-forming S strain were isolated, and their fermentation ability and acetic acid diffusion activity were compared. The results suggest that pellicle formation is directly related to acetic acid resistance ability, and thus is important to acetic acid fermentation in these A. pasteurianus strains. PMID:20699583

Kanchanarach, Watchara; Theeragool, Gunjana; Inoue, Taketo; Yakushi, Toshiharu; Adachi, Osao; Matsushita, Kazunobu

2010-01-01

114

Fluorescence quenching of etilefrine by acetate anion  

NASA Astrophysics Data System (ADS)

Acid dissociation in the excited state of antihypotensor drug etilefrine [2-(ethylamino1-3-hydroxyphenyl)ethanol] is studied. Fluorescence of etilefrine decreases at pH<7 and is related to phenolic group dissociation. However, intensity of etilefrine fluorescence diminishes as the concentration of the acetate anion increases at pH>7. Analyses of the absorption and fluorescence spectra of aqueous solutions of etilefrine in the presence of acetate anions have been made. Considering the existence of an equilibrium in the excited state the values of 3.47×10 -9 and 0.216×10 -9 M -1 s -1 have been obtained for the rate constants for direct and inverse reactions, respectively. Moreover, the lifetime ( ?0'=0.58×10 -9 s) and quantum yield (0.01) of non-protonated etilefrine have been determined. Our results seem to support the existence of a dynamic quenching process based on a proton transfer mechanism induced by acetate anions. This process could represent a serious inconvenience in analytical fluorimetric techniques taking into account that the acetic acid/acetate pair is commonly used as a buffer. Additional fluorescence quenching by H + ions could be involved in acid aqueous mediums. At high concentrations of acetic acid, a value of 2.98×10 -9 M -1 s -1 for the bimolecular constant for the quenching by H + has been calculated.

Quintero Osso, B.; Carazo Rodríguez, F. M.; Morales Domingo, J. J.; Cabeza González, M. C.; Thomas Gómez, J.

1999-02-01

115

Acetate limitation and nitrite accumulation during denitrification  

SciTech Connect

Nitrite accumulated in denitrifying activated sludge mixed liquor when the carbon and electron source, acetate, was limited. If acetate was added to obtain a carbon-to-nitrogen (C:N) ratio in the range of 2:1 to 3:1, nitrate was completely consumed at the same rate with no nitrite accumulation, indicating that nitrate concentration controlled the respiration rate as long as sufficient substrate was present. However, when acetate was reduced to a C:N ratio of 1:1, while nitrate continued to be consumed, > 50% of the initial nitrate-nitrogen accumulated as nitrite and 29% persisted as nitrite throughout an endogenous denitrification period of 8--9 h. While nitrite accumulated during acetate-limited denitrification, the specific nitrate reduction rate increased significantly compared with the rate when excess acetate was provided as follows: 0.034 mg-NO{sub 3}-N/mg-mixed liquid volatile suspended solids/h versus 0.023 mg-NO{sub 3}-N/mg-mixed liquid volatile suspended solids/h, respective. This may be explained by nitrate respiration out-competing nitrite respiration for limited acetate electrons. Complete restoration of balanced denitrification and elimination of nitrite accumulation during denitrification required several weeks after the C:N ratio was increased back to 2:1.

Oh, J. [Pohang Univ. of Science and Technology (Korea, Republic of). School of Environmental Engineering] [Pohang Univ. of Science and Technology (Korea, Republic of). School of Environmental Engineering; Silverstein, J. [Univ. of Colorado, Boulder, CO (United States)] [Univ. of Colorado, Boulder, CO (United States)

1999-03-01

116

Synthesis and properties of cyclic acetal biomaterials.  

PubMed

There is an increasing need to develop new biomaterials as tissue engineering scaffolds. Unfortunately, many of the materials that have been studied for these purposes are polyesters that hydrolytically degrade into acidic products, which may harm the surrounding tissue, and lead to accelerated degradation of the biomaterial. To overcome this disadvantage, a novel class of biomaterials based on a cyclic acetal unit has been created. Specifically, materials based upon the monomer 5-ethyl-5-(hydroxymethyl)-beta,beta-dimethyl-1,3-dioxane-2-ethanol diacrylate (EHD) is examined. This study investigates the effects of fabrication parameters, including initiator content, volume of diluent, and volume of accelerant, on several properties of EHD networks. Twelve different formulations were fabricated by varying the three parameters in a factorial design. The effects of the fabrication parameters on properties of the EHD networks were examined. Results show that the volume of accelerant most affected the EHD network gelation time, while the volume of diluent most affected the maximum reaction temperature, sol fraction, and degree of swelling. Cell viability on the EHD networks varied between (18 +/- 6)% and (57 +/- 10)% of the control at 4 h, and between (36 +/- 14)% and (140 +/- 50)% of the control at 8 h. These results indicate that it is possible to control the properties of the EHD networks by varying the fabrication parameters, and that EHD networks support a viable cell population. PMID:17177269

Moreau, Jennifer L; Kesselman, Dafna; Fisher, John P

2007-06-01

117

Acetate transport and utilization in the rat brain.  

PubMed

Acetate, a glial-specific substrate, is an attractive alternative to glucose for the study of neuronal-glial interactions. The present study investigates the kinetics of acetate uptake and utilization in the rat brain in vivo during infusion of [2-13C]acetate using NMR spectroscopy. When plasma acetate concentration was increased, the rate of brain acetate utilization (CMR(ace)) increased progressively and reached close to saturation for plasma acetate concentration > 2-3 mM, whereas brain acetate concentration continued to increase. The Michaelis-Menten constant for brain acetate utilization (K(M)(util) = 0.01 +/- 0.14 mM) was much smaller than for acetate transport through the blood-brain barrier (BBB) (K(M)(t) = 4.18 +/- 0.83 mM). The maximum transport capacity of acetate through the BBB (V(max)(t) = 0.96 +/- 0.18 micromol/g/min) was nearly twofold higher than the maximum rate of brain acetate utilization (V(max)(util) = 0.50 +/- 0.08 micromol/g/min). We conclude that, under our experimental conditions, brain acetate utilization is saturated when plasma acetate concentrations increase above 2-3 mM. At such high plasma acetate concentration, the rate-limiting step for glial acetate metabolism is not the BBB, but occurs after entry of acetate into the brain. PMID:19393008

Deelchand, Dinesh K; Shestov, Alexander A; Koski, Dee M; U?urbil, Kâmil; Henry, Pierre-Gilles

2009-05-01

118

Acetate and hypercalciuria during total parenteral nutrition13  

Microsoft Academic Search

Hypercalciuria and negative calcium balance are complications oftotal par- enteral nutrition (TPN). Because metabolism ofthe TPN formula generates an acid load that can induce hypercalciuria, we evaluated the effect ofsupplementing the formula with acetate. In a randomized crossover study six patients on continuous and six on cyclic TPN received no added acetate or 160 mmol acetate\\/d replacing 160 mmol chloride\\/d

Charles H Berkelhammer; Richard J Wood; Michael D Sitrin

119

Acetate reduces microglia inflammatory signaling in vitro  

PubMed Central

Acetate supplementation increases brain acetyl-CoA and histone acetylation and reduces lipopolysaccharide (LPS)-induced neuroglial activation and interleukin (IL)-1? expression in vivo. To determine how acetate imparts these properties, we tested the hypothesis that acetate metabolism reduces inflammatory signaling in microglia. To test this, we measured the effect acetate treatment had on cytokine expression, mitogen-activated protein kinase (MAPK) signaling, histone H3 at lysine 9 acetylation, and alterations of nuclear factor-kappa B (NF-?B) in primary and BV-2 cultured microglia. We found that treatment induced H3K9 hyperacetylation and reversed LPS-induced H3K9 hypoacetylation similar to that found in vivo. LPS also increased IL-1?, IL-6 and tumor necrosis factor-alpha (TNF-?) mRNA and protein, while treatment returned the protein to control levels and only partially attenuated IL-6 mRNA. In contrast, treatment increased mRNA levels of transforming-growth factor-?1 (TGF-?1) and both IL-4 mRNA and protein. LPS increased p38 MAPK and JNK phosphorylation at 4 and 2–4 hr respectively, while treatment reduced p38 MAPK and JNK phosphorylation only at 2 hr. In addition, treatment reversed the LPS-induced elevation of NF-?B p65 protein and phosphorylation at serine 468 and induced acetylation at lysine 310. These data suggest that acetate metabolism reduces inflammatory signaling and alters histone and non-histone protein acetylation. PMID:22924711

Soliman, Mahmoud L.; Puig, Kendra L.; Combs, Colin K.; Rosenberger, Thad A.

2012-01-01

120

The behaviour of tungsten electrodes in a mixture of acetic acid and acetic anhydride  

Microsoft Academic Search

Summary Tungsten electrodes have advantageously been used for potentiometric end-point detection in perchloric acid titration of bases in a mixture of acetic acid and acetic anhydride. They have also given good results in biamperometric detection of the equivalence point in continuous coulometric titration of small quantities of bases and acids in the same solvent. Tungsten electrodes in the presence of

Tibor J. Pastor; Vilim J. Vajgand

1976-01-01

121

Acetic acid mediated interactions between alumina surfaces  

NASA Astrophysics Data System (ADS)

Low-molecular-weight organic acids have been known to modify colloidal stability of alumina-based suspensions. We investigated interaction forces between alumina surfaces mediated by acetic acid which is one of the simplest organic acids. Forces between alumina surfaces were measured using the colloid-probe method of atomic force microscope (AFM). Repulsive forces attributed to steric repulsion due to adsorbed molecules and electrostatic repulsion dominated the interaction. Results of rheological characterization of the alumina slurry containing acetic acid supported the finding.

Sato, Kimiyasu; Y?lmaz, Hüseyin; Ijuin, Atsuko; Hotta, Yuji; Watari, Koji

2012-02-01

122

Immunotoxicity of Trenbolone Acetate in Japanese Quail  

Microsoft Academic Search

Trenbolone acetate is a synthetic androgen that is currently used as a growth promoter in many meat-exporting countries. Despite industry laboratories classifying trenbolone as nonteratogenic, data showed that embryonic exposure to this androgenic chemical altered development of the immune system in Japanese quail. Trenbolone is lipophilic, persistent, and released into the environment in manure used as soil fertilizer. This is

Michael James Quinn; Moira McKernan; Emma T. Lavoie; Mary Ann Ottinger

2006-01-01

123

21 CFR 73.2396 - Lead acetate.  

Code of Federal Regulations, 2013 CFR

21 Food and Drugs 1 2013-04-01 2013-04-01...acetate. 73.2396 Section 73.2396 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT...than 4.7 and not more than 5.8. Arsenic (as As), not more than 3 parts...

2013-04-01

124

Drying Cellulose Acetate Reverse Osmosis Membranes.  

National Technical Information Service (NTIS)

The membranes currently used in reverse osmosis for desalination are made of cellulose acetate. Modified membranes, because they contain a large number of pores, contain large quantities of water, 60 to 70 wt. %. If this water is allowed to evaporate unde...

K. D. Vos, F. O. Burris

1967-01-01

125

Heat Bonding of Irradiated Ethylene Vinyl Acetate  

NASA Technical Reports Server (NTRS)

Reliable method now available for joining parts of this difficult-tobond material. Heating fixture encircles ethylene vinyl acetate multiplesocket part, providing heat to it and to tubes inserted in it. Fixtures specially designed to match parts to be bonded. Tube-and-socket bonds made with this technique subjected to tensile tests. Bond strengths of 50 percent that of base material obtained consistently.

Slack, D. H.

1986-01-01

126

Process for the preparation of vinyl acetate  

DOEpatents

This invention pertains to the preparation of vinyl acetate by contacting within a contact zone a mixture of ketene and acetaldehyde with an acid catalyst at about one bar pressure and between about 85 and 200 C and removing the reaction products from the contact zone.

Tustin, G.C.; Zoeller, J.R.; Depew, L.S.

1998-02-17

127

Strengths of the Chloro-acetic Acids  

Microsoft Academic Search

IT is well known that the introduction of chlorine atoms into acetic acid causes a rapid rise of dissociation constant (see ). If changes in the value of K are taken as a measure of the effect of the chlorine atoms, it would appear that the second chlorine atom has a greater effect than the first, and the third a

John Shorter; F. J. Stubbs

1949-01-01

128

Process for the preparation of vinyl acetate  

DOEpatents

This invention pertains to the preparation of vinyl acetate by contacting within a contact zone a mixture of ketene and acetaldehyde with an acid catalyst at about one bar pressure and between about 85.degree. and 200.degree. C. and removing the reaction products from the contact zone.

Tustin, Gerald Charles (Kingsport, TN); Zoeller, Joseph Robert (Kingsport, TN); Depew, Leslie Sharon (Kingsport, TN)

1998-01-01

129

Corrosion of stainless steel during acetate production  

SciTech Connect

Corrosion of types 304, 304L, 316, and 316L stainless steel (SS) during the esterification of acetic acid and alcohol or glycol ether was investigated. The catalyst for this reaction, sulfuric acid or para-toluene sulfonic acid (PTSA), was shown to cause more corrosion on reactor equipment than CH{sub 3}COOH under the process conditions commonly practiced in industry. The corrosive action of the catalyst occurred only in the presence of water. Thus, for the batch processes, corrosion occurred mostly during the initial stage of esterification, where water produced by the reaction created an aqueous environment. After water was distilled off, the corrosion rate declined to a negligible value. The corrosion inhibitor copper sulfate, often used in industrial acetate processes, was found to work well for a low-temperature process (< 95 C) such as in production of butyl acetate, but it accelerated corrosion in the glycol ether acetate processes where temperatures were > 108 C. Process conditions that imparted low corrosion rates were determined.

Qi, J.S.; Lester, G.C. [Occidental Chemical Corp. Technology Center, Grand Island, NY (United States)

1996-07-01

130

Fermentative biohydrogen production from lactate and acetate.  

PubMed

In this study, a continuous-flow stirred tank reactor (CSTR) fed with lactate and acetate was operated to enrich hydrogen-producing bacteria. By varying the influent substrate concentrations and hydraulic retention times (HRT), the volumetric loading rate (VLR) of 55.64 kg-COD/m(3)/day seemed to be optimum for this enriched culture for fermentative hydrogen production from lactate and acetate. The results of batch experiments confirmed that the enriched culture tended to fulfill the e(-) equiv requirement for cell growth at a lower VLR condition (21.77 kg-COD/m(3)/day), while it could largely distribute the e(-) equiv for hydrogen production at a higher VLR condition. However, a maximum lactate/acetate concentration allowed for enriching this culture existed, especially at a lower HRT condition in which wash-out can be an issue for this enriched culture. Finally, the results of cloning and sequencing indicated that Clostridium tyrobutyricum was considered the major hydrogen-producing bacteria in the CSTR fed with lactate and acetate. PMID:22318084

Wu, Chao-Wei; Whang, Liang-Ming; Cheng, Hai-Hsuan; Chan, Kan-Chi

2012-06-01

131

Recovery of acetic acid from dilute aqueous solutions using catalytic dehydrative esterification with ethanol.  

PubMed

We have developed a direct esterification of aqueous acetic acid with ethanol (molar ratio=1:1) catalyzed by polystyrene-supported or homogeneous sulfonic acids toward the recovery of acetic acid from wastewater in chemical plants. The equilibrium yield was significantly increased by the addition of toluene, which had a high ability to extract ethyl acetate from the aqueous phase. It was shown that low-loading and alkylated polystyrene-supported sulfonic acid efficiently accelerated the reaction. These results suggest that the construction of hydrophobic reaction environments in water was critical in improving the chemical yield. Addition of inorganic salts was also effective for the reaction under not only biphasic conditions (toluene-water) but also toluene-free conditions, because the mutual solubility of ethyl acetate and water was suppressed by the salting-out effect. Among the tested salts, CaCl(2) was found to be the most suitable for this reaction system. PMID:23290939

Yagyu, Daisuke; Ohishi, Tetsuo; Igarashi, Takeshi; Okumura, Yoshikuni; Nakajo, Tetsuo; Mori, Yuichiro; Kobayashi, Sh?

2013-03-01

132

Ethyl acetate extraction from a Chinese herbal formula, Jiedu Xiaozheng Yin, inhibits the proliferation of hepatocellular carcinoma cells via induction of G0/G1 phase arrest in vivo and in vitro.  

PubMed

Jiedu Xiaozheng Yin (JXY), a polyherbal formula of traditional Chinese medicine (TCM), has been used to treat various kinds of cancer in China. However, the mechanism of its anticancer activity has yet to be elucidated. Air-dried herbs were extracted with reagents of different polarity. HepG2 cells were treated with different doses of ethyl acetate extract (EE-JXY) and chloroform extract (CE-JXY) for 24 h. Cell viability was detected by MTT assay. Colony formation ability was also evaluated. Cell cycle was evaluated by FACS. Tumor bearing BALB/c nude mice was treated with EE-JXY (0.06 g/kg) for 20 days. Tumor volume and weight were monitored. The percentage of PCNA-positive cells and the level of G1 phase proteins [cyclin-dependent kinase2 (CDK2), cyclin?dependent kinase4 (CDK4), cyclin D and cyclin E and G2 phase proteins [cyclin-dependent kinase1 (CDK1), cyclin A and cyclin B] were detected by immunohistochemistry and western blotting. EE-JXY and CE-JXY dose-dependently inhibited the growth of HepG2 cells (P<0.01 for both). Furthermore, EE-JXY inhibited the formation of cell colonies and blocked the cell cycle to G1 phase in a dose-dependent manner (P<0.01 for all). EE-JXY showed an obviously antitumor effect in vivo (P<0.05). Further investigation showed that EE-JXY decreased the proliferation index of tumors (P<0.01) through increasing the expression of G1-related proteins (cyclin D and cyclin E, P<0.05 and P<0.01). These results suggested that JXY inhibits the growth of HepG2 cells at least via arresting the cell cycle at the G0/G1 phase. PMID:23165653

Cao, Zhiyun; Lin, Wei; Huang, Zhengrong; Chen, Xuzheng; Zhao, Jinyan; Zheng, Liangpu; Ye, Hongzhi; Liu, Zhizhen; Liao, Lianming; Du, Jian

2013-01-01

133

The microwave spectrum of n-hexyl acetate and structural aspects of n-alkyl acetates  

NASA Astrophysics Data System (ADS)

The microwave spectrum of n-hexyl acetate was recorded in the range of 10-13.5 GHz using the Aachen MB-FTMW spectrometer. The rotational constants of the most abundant conformer were determined to be A = 3.3591100(32) GHz, B = 0.39596553(53) GHz, and C = 0.36999804(31) GHz. Quantum chemical calculations for specific conformers were carried out at the MP2/6-311++G(d,p) level. The programs XIAM and BELGI were used to analyze the internal rotation of the acetyl methyl group. The observed conformer of n-hexyl acetate was compared to the lowest energy conformers of n-butyl acetate and n-pentyl acetate.

Attig, T.; Kannengießer, R.; Kleiner, I.; Stahl, W.

2014-04-01

134

Trypanosomatidae Produce Acetate via a Mitochondrial Acetate:Succinate CoA Transferase  

Microsoft Academic Search

Hydrogenosome-containing anaerobic protists, such as the trichomonads, produce large amounts of acetate by an acetate:succinate CoA transferase (ASCT)\\/succinyl CoA synthetase cycle. The notion that mitochondria and hydrogenosomes may have originated from the same alpha -proteobacterial endosymbiont has led us to look for the presence of a similar metabolic pathway in trypanosomatids because these are the earliest-branching mitochondriate eukaryotes and because

Jaap J. van Hellemond; Fred R. Opperdoes; Aloysius G. M. Tielens

1998-01-01

135

Solid–liquid equilibrium in the acetic acid–acetophenone and acetic acid–formamide systems  

Microsoft Academic Search

Solid–liquid equilibrium in the binary systems acetic acid–acetophenone and acetic acid–formamide was determined from time–temperature cooling and warming curves. The first system shows a sagged curve with a eutectic point at x1?0.6 and T=267.18 K. In the second system a solid compound (2:1) was found and an equilibrium constant of the compound dissociation was calculated.

I. Malijevská; Z. Sedláková

2006-01-01

136

Synthesis of N-acyl-N,O-acetals mediated by titanium ethoxide.  

PubMed

N-Acyl-N,O-acetals are present in a number of bioactive natural products, and this unusual functional group can act as a synthetic precursor to unstable reactive N-acylimines. In this paper, a variety of N-acyl-O-ethyl-N,O-acetals was concisely prepared under mild conditions mediated by titanium ethoxide (Ti(OEt)4). The method also offers a new strategy to make other O-alkyl-N,O-acetals. Furthermore, this strategy was extended to the synthesis of an analogue of the natural product turtschamide. PMID:24308842

Li, Min; Luo, Bingling; Liu, Qi; Hu, Yumin; Ganesan, A; Huang, Peng; Wen, Shijun

2014-01-01

137

21 CFR 173.228 - Ethyl acetate.  

Code of Federal Regulations, 2010 CFR

... (b) The additive is used in accordance with current good manufacturing practice as a solvent in the decaffeination of coffee and tea. [47 FR 146, Jan. 5, 1982, as amended at 49 FR 28548, July 13,...

2010-04-01

138

21 CFR 173.228 - Ethyl acetate.  

... (b) The additive is used in accordance with current good manufacturing practice as a solvent in the decaffeination of coffee and tea. [47 FR 146, Jan. 5, 1982, as amended at 49 FR 28548, July 13, 1984; 78 FR 71466, Nov. 29,...

2014-04-01

139

Biogas Production through the Syntrophic Acetate-Oxidising Pathway  

E-print Network

retention time OLR Organic loading rate PCR Polymerase chain reaction qPCR Quantitative polymerase chain reaction RNA Ribonucleic acid SAO Syntrophic acetate oxidation SAOB Syntrophic acetate-oxidising bacteria

140

Separating acetic acid from furol (furfural) by electrodialysis method  

SciTech Connect

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

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

1981-01-01

141

l-Lysinium trifluoro-acetate.  

PubMed

Ions of the title compound, C(6)H(15)N(2)O(2) (+)·C(2)F(3)O(2) (-), a new organic nonlinear optical crystal, are linked by N-H?O hydrogen-bonding inter-actions. Both the amino groups of the l-lysinium cation are protonated. A three-dimensional network of hydrogen bonds is observed, forming a closed ring. Inter-molecular N-H?O hydrogen bonds involving l-lysinium cations and trifluoro-acetate anions link the ions into extended chains which run parallel to the [010] direction. The F atoms of the trifluoro-acetate anion are disordered over two sites with site occupancies of 0.423?(18) and 0.577?(18). The asymmetric unit consists of two cations and two anions. PMID:21201423

Sun, Zhi Hua; Fan, Jian Dong; Zhang, Guang Hui; Wang, Xin Qiang; Xu, Dong

2008-01-01

142

Functional Properties of Extruded Starch Acetate Blends  

Microsoft Academic Search

Starch acetate, with degree of substitution of 2, was blended with 0, 7.5 and 15% polylactic acid (PLA), Eastar Bio Copolyester 14766 (EBC) or Mater-Bi ZF03U (MBI) and 10%, 13%, or 16% (d.b.) ethanol and twin-screw extruded at 160°C barrel temperature. Physical characteristics of the extrudates, such as radial expansion ratio, unit and bulk densities, and of the mechanical properties,

J. Guan; Q. Fang; M. A. Hanna

2004-01-01

143

Corrosion of Stainless Steel During Acetate Production  

Microsoft Academic Search

Corrosion of types 304, 304L, 316, and 316L stainless steel (SS) during the esterification of acetic acid and alcohol or glycol ether was investigated. The catalyst for this reaction, sulfuric acid or para-toluene sulfonic acid (PTSA), was shown to cause more corrosion on reactor equipment than CHâCOOH under the process conditions commonly practiced in industry. The corrosive action of the

J. S. Qi; G. C. Lester

1996-01-01

144

Lithium acetate transformation of yeast Maitreya Dunham August 2004  

E-print Network

Lithium acetate transformation of yeast Maitreya Dunham August 2004 Original protocol from Katja until the OD600 is around 0.7-0.8 (~7 hours). Spin down the cells. Resuspend in 5 ml lithium acetate mix. Spin. Resuspend in 0.5 ml lithium acetate mix. Transfer to an eppendorf tube. Incubate 60 minutes

Dunham, Maitreya

145

Development of an Amperometric Acetic Acid Sensor in Organic System  

Microsoft Academic Search

An amperometric method was developed by using a lead working electrode in acetonitrile organic solution for detecting acetic acid. The mechanisms of electrochemical reaction were corresponding to the reduction of acetic ions in acetonitrile organic solution. The steady state amperometric current resulted from the reduction of acetic ions to produce the aldehyde in a two-electron process. In the organic sensing

Shin Lin; Tse-Chuan Chou

146

Effects of nitrobenzene and zinc on acetate utilizing methanogens  

Microsoft Academic Search

Determination of anaerobic degradation rates and toxic effects of nitrobenzene (NB) on acetate utilizing methanogens was the first objective of this research. Serum bottles were used for anaerobic toxicity assays with an acetate enrichment culture of methanogens. Ten mg\\/l of nitrobenzene did not inhibit total gas production in the acetate enrichment methanogenic culture. Twenty and thirty mg\\/l of nitrobenzene caused

Sanjoy K. Bhattacharya; Mingbo Qu; Richard L. Madura

1996-01-01

147

Thermochemical characteristics of cellulose acetates with different degrees of acetylation  

NASA Astrophysics Data System (ADS)

The standard enthalpies of combustion and formation of cellulose acetates with different degrees of acetylation are determined. It is established that there is a proportional dependence of these thermochemical characteristics vs. the degree of acetylation, weight fraction of bonded acetic acid, and molar mass of the repeating unit of cellulose acetates.

Larina, V. N.; Ur'yash, V. F.; Kushch, D. S.

2012-12-01

148

Acetate supplementation attenuates lipopolysaccharide-induced neuroinflammation  

PubMed Central

Glyceryl triacetate (GTA), a compound effective at increasing circulating and tissue levels of acetate was used to treat rats subjected to a continual 28 day intra-ventricular infusion of bacterial lipopolysaccharide (LPS). This model produces a neuroinflammatory injury characterized by global neuroglial activation and a decrease in choline acetyltransferase immunoreactivity in the basal forebrain. During the LPS infusion, rats were given a daily treatment of either water or GTA at a dose of 6g/kg by oral gavage. In parallel experiments free-CoA and acetyl-CoA levels were measured in microwave fixed brains and flash frozen heart, liver, kidney and muscle following a single oral dose of GTA. We found that a single oral dose of GTA significantly increased plasma acetate levels by 15 min and remained elevated for up to 4 hr. At 30 min the acetyl-CoA levels in microwave-fixed brain and flash frozen heart and liver were increased at least 2.2-fold. The concentrations of brain acetyl-CoA was significantly increased between 30 and 45 min following treatment and remained elevated for up to 4 hr. The concentration of free-CoA in brain was significantly decreased compared to controls at 240 min. Immunohistochemical and morphological analysis demonstrated that a daily treatment with GTA significantly reduced the percentage of reactive GFAP-positive astrocytes and activated CD11b-positive microglia by 40–50% in rats subjected to LPS-induced neuroinflammation. Further, in rats subjected to neuroinflammation, GTA significantly increased the number of ChAT-positive cells by 40% in the basal forebrain compared to untreated controls. These data suggest that acetate supplementation increases intermediary short chain acetyl-CoA metabolism and that treatment is potentially anti-inflammatory and neuroprotective with regards to attenuating neuroglial activation and increasing ChAT immunoreactivity in this model. PMID:21272004

Reisenauer, Chris J.; Bhatt, Dhaval P.; Mitteness, Dane J.; Slanczka, Evan R.; Gienger, Heidi M.; Watt, John A.; Rosenberger, Thad A.

2011-01-01

149

2-Amino-pyridinium trifluoro-acetate.  

PubMed

The asymmetric unit of the title compound, C(5)H(7)N(2) (+)·C(2)F(3)O(2) (-), contains four independent 2-amino-pyridinium cations and four independent trifluoro-acetate anions. In the crystal structure, these ions are linked by N-H?O hydrogen bonds, forming four cation-anion pairs each containing an R(2) (2)(8) ring motif. The ion pairs are linked into two independent chains along [100] by N-H?O hydrogen bonds. In addition, C-H?O and C-H?F hydrogen bonds and ??? inter-actions [centoid-centroid separation = 3.6007?(17)?Å] are observed. PMID:21580433

Hemamalini, Madhukar; Fun, Hoong-Kun

2010-01-01

150

Methods for isolation of auxotrophic mutants of methanobacterium ivanovii and initial characterization of acetate auxotrophs  

SciTech Connect

To develop a biochemical genetic approach to understanding cell carbon synthesis or metabolic pathways in methanogens, Methanobacterium ivanovii was selected as a model organism for genetic manipulation studies. The organism displayed a colony size of 3 to 6 mm in less than 2 weeks and had a plating efficiency of about 90%, which made it suitable for replica plating. Mutagenesis and selection techniques were developed for selection of acetate auxotrophs. Chemical mutagenesis with ethyl methanesulfonate, followed by enrichment with bacitracin as a selective agent, resulted in stable acetate auxotrophs. M. ivanovii was very sensitive to UV, but UV-induced acetate auxotrophs were unstable and reverted within two to four transfers. The acetate auxotrophs were analyzed in relation to wild type for carbon monoxide dehydrogenase enzyme activity.

Jain, M.K.; Zeikus, J.G.

1987-06-01

151

Antimicrobial and Cytotoxic Activity of Di-(2-ethylhexyl) Phthalate and Anhydrosophoradiol-3-acetate Isolated from Calotropis gigantea (Linn.) Flower  

PubMed Central

A phytochemical study on the flowe r of Calotropis gigantea (Linn.) using silica gel column chromatography and preparative thin layer chromatography, led to the first time isolation of Di-(2-ethylhexyl) phthalate (compound 1) and anhydrosophoradiol-3-acetate (compound 2). The structures of these compounds were confirmed by spectroscopic analyses (IR, HRTOFMS and NMR). The antibacterial and antifungal activities of ethyl acetate extract, compound 1 and compound 2 were measured using the disc diffusion method. Ethyl acetate extract and compound 1 presented better results than compound 2. The minimum inhibitory concentrations (MICs) of the extract and compounds were found to be in the range of 16~128 µg/ml. The cytotoxicity (LC50) against brine shrimp nauplii (Artemia salina) were also evaluated and found to be 14.61 µg/ml for ethyl acetate, 9.19 µg/ml for compound 1 and 15.55 µg/ml for compound 2. PMID:23983504

Habib, M. Rowshanul

2009-01-01

152

(Prefix) Chemical Company Amount Location Quantity(>1) acetone dimethyl acetal MCB 500g 1013 YC #1  

E-print Network

(Prefix) Chemical Company Amount Location Quantity(>1) acetone dimethyl acetal MCB 500g 1013 YC #1 3,5-bis (trifluoromethyl)-analine Aldrich 50g freezer 2- (trimethylsilyl)ethanol Aldrich 10g freezer 18-crown-6 Aldrich 1g Dry Box 1-ethyl-3-(3-dimethylaminopropyl) carbodiimidethermo scientific 5g

Turro, Claudia

153

Addition of Silyl Ketene Acetals to Nitrones Catalyzed by Lanthanide Triflates  

Microsoft Academic Search

?-Aryl-N-phenyl nitrones reacted with silyl ketene acetals mediated by lanthanum trifloromethanesulfonate (triflate) to afford the addition product in excellent yield under mild conditions. ?-Aryl-N-tert-butyl nitrone reacted with ethyl trimethylsilylacetate to yield the unexpected ?,?-unsaturated ester in a 100% E-form. A possible mechanism for the process is discussed.

Changtao Qian; Longcheng Wang

2000-01-01

154

21 CFR 584.200 - Ethyl alcohol containing ethyl acetate.  

Code of Federal Regulations, 2011 CFR

... Section 584.200 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT...SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS...RECOGNIZED AS SAFE IN FEED AND DRINKING WATER OF ANIMALS Listing of...

2011-04-01

155

21 CFR 584.200 - Ethyl alcohol containing ethyl acetate.  

Code of Federal Regulations, 2010 CFR

... Section 584.200 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT...SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS...RECOGNIZED AS SAFE IN FEED AND DRINKING WATER OF ANIMALS Listing of...

2010-04-01

156

21 CFR 584.200 - Ethyl alcohol containing ethyl acetate.  

Code of Federal Regulations, 2012 CFR

... Section 584.200 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT...SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS...RECOGNIZED AS SAFE IN FEED AND DRINKING WATER OF ANIMALS Listing of...

2012-04-01

157

21 CFR 584.200 - Ethyl alcohol containing ethyl acetate.  

Code of Federal Regulations, 2013 CFR

... Section 584.200 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT...SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS...RECOGNIZED AS SAFE IN FEED AND DRINKING WATER OF ANIMALS Listing of...

2013-04-01

158

Structural changes of human serum albumin induced by cadmium acetate.  

PubMed

The structural changes of human serum albumin (HSA) induced by the addition of cadmium acetate were systematically investigated using UV-vis absorption, circular dichroism (CD), synchronous, and three-dimentional (3D) fluorescence methods. The fluorescence spectra suggested the formation of cadmium acetate-HSA complex. UV absorption result indicated that the interaction between cadmium acetate and HSA could lead to the alteration of the protein skeleton. The structural analysis according to CD method showed that the cadmium acetate binding altered HSA conformation with a major reduction of ?-helix, inducing a partial protein unfolding. Synchronous fluorescence spectra suggested that cadmium acetate was situated closer to tryptophan residue compared to tyrosine residues, making tryptophan residue locate in a more hydrophobic environment. 3D fluorescence demonstrated that cadmium acetate could induce the HSA aggregation and cause a slight unfolding of the polypeptide backbone of the protein. PMID:24771482

Chen, Mingmao; Guo, Hao; Liu, Yan; Zhang, Qiqing

2014-06-01

159

Acetate absorption and metabolism in the rabbit hindgut.  

PubMed Central

Acetate disappearance from the loops of the hindgut in the rabbit was evaluated by measuring variations in the concentration of acetate in caecocolonic loops and differences in the arterial and venous plasma. In vivo metabolism in gut and liver tissues was studied after introduction of (1-14C) acetate into caecocolonic loops. The rate of disappearance from the loops was quantitatively significant and showed little variation irrespective of the location in the hindgut. Hindgut tissue metabolised acetate and the intensity of the metabolism varied with the segment studied. The distal position of the gut showed by far the highest acetate uptake. Radioactivity was found in a certain number of free amino acids, organic acids, and sugars. Acetate was mainly converted into aspartate and glutamate. These can be considered as 'stock forms' which can be diverted either towards oxidative metabolism or towards protein synthesis. Images Fig. 1 PMID:4007603

Marty, J F; Vernay, M Y; Abravanel, G M

1985-01-01

160

Effect of medroxyprogesterone acetate (Provera) on ovarian radiosensitivity  

SciTech Connect

Medroxyprogesterone acetate (Provera) is a drug that is commonly given to young women with cancer during chemotherapy and radiation to control heavy bleeding associated with anovulation. Because hypothalamic-pituitary-ovarian suppression has been associated with ovarian protection from the effects of chemotherapy and medroxyprogesterone acetate has been identified as a radiosensitizing agent, we explored the effects of medroxyprogesterone acetate on a rat model with known radiation injury characteristics. Sprague-Dawley rats were treated with medroxyprogesterone acetate or vehicle from day 22 to day 37 of life and were either irradiated or sham-irradiated on day 30 of life and then killed on day 44. Radiation with medroxyprogesterone acetate administration produced a greater loss in preantral and healthy control follicles than in control follicles. No suppression of luteinizing hormone or follicle-stimulating hormone had occurred by day 30 but ovarian glutathione content was reduced. These findings indicate that the administration of medroxyprogesterone acetate with radiotherapy may enhance ovarian injury.

Jarrell, J.; YoungLai, E.V.; McMahon, A.; Barr, R.; O'Connell, G.; Belbec, L.

1989-04-01

161

Nutrient requirements for high rate conversion of acetate to methane  

Microsoft Academic Search

In this research, nutrient requirements for high rate conversion of acetate to methane were examined with acetate enrichment cultures at 35°C. By employing a pH stat as the cultivation system, the pH and acetate concentration were maintained, respectively, at about 6.8 and greater than or equal to 2000 mg\\/l in the reactor. Ni and Fe limitation in the pH stat

Takashima

1987-01-01

162

Mesophilic syntrophic acetate oxidation during methane formation in biogas reactors  

Microsoft Academic Search

The reaction pathway for the formation of methane from acetate was investigated in sludge from 13 different biogas reactors. By following the conversion of [2-14C]acetate and [14C]bicarbonate it was shown that methane formation by syntrophic acetate oxidation was the dominating mechanism for acetotrophic methanogenesis in sludge containing high levels of salts, mainly ammonium, and volatile fatty acids. In one biogas

Anna Schnürer; Gerhard Zellner; Bo H. Svensson

1999-01-01

163

Synthesis and characterization of cyclic acetal based degradable hydrogels.  

PubMed

While many synthetic, hydrolytically degradable hydrogels have been developed for biomedical applications, there are only a few examples whose polymer backbone does not form acidic products upon degradation. In order to address this concern, we proposed to develop a hydrogel based on a cyclic acetal unit that produces diols and propanals upon hydrolytic degradation. In particular, we proposed the fabrication of hydrogels formed by the free radical polymerization of two diacrylate monomers, 5-ethyl-5-(hydroxymethyl)-beta,beta-dimethyl-1,3-dioxane-2-ethanol diacrylate (EHD), a cyclic acetal having two acryl groups, and poly(ethylene glycol)diacrylate (PEGDA). However, the hydrophobicity of the EHD monomer inhibits hydrogel fabrication. Therefore this work develops a strategy to form hydrogels with a co-monomer system, one of which is hydrophobic, and subsequently describes the properties of the resulting hydrogel. Using benzoyl peroxide as an initiator and N,N-dimethyl-p-toluidine as an accelerator, the EHD and PEGDA monomers were reacted in an acetone/water co-solvent system. The chemical structure of the resulting EH-PEG [5-ethyl-5-(hydroxymethyl)-beta,beta-dimethyl-1,3-dioxane-2-ethanol-co-PEG] hydrogel was then characterized by FT-IR. Physicochemical properties of the EH-PEG hydrogel, including swelling degree, sol fraction, and contact angle, were determined so as to characterize the properties of these materials and ultimately investigate their use in drug delivery and tissue engineering applications. Results showed that EH-PEG hydrogel may be formed using the co-solvent system. Further results indicated that swelling degree is dependent upon initiator concentration, monomer concentration, and molar ratios of monomers, while sol fraction significantly depended on initiator concentration and monomer concentration, only. These results demonstrate the ability to fabricate hydrogels using EHD and PEGDA system as well as to control the properties of the resulting hydrophilic networks. PMID:17888640

Kaihara, Sachiko; Matsumura, Shuichi; Fisher, John P

2008-01-01

164

21 CFR 522.1410 - Sterile methylprednisolone acetate suspension.  

Code of Federal Regulations, 2010 CFR

...with methylprednisolone acetate, as with other corticoids, is contraindicated in animals with arrested tuberculosis, peptic ulcer, and Cushing's syndrome. The presence of active tuberculosis, diabetes mellitus, osteoporosis, renal...

2010-04-01

165

21 CFR 522.1410 - Sterile methylprednisolone acetate suspension.  

Code of Federal Regulations, 2011 CFR

...with methylprednisolone acetate, as with other corticoids, is contraindicated in animals with arrested tuberculosis, peptic ulcer, and Cushing's syndrome. The presence of active tuberculosis, diabetes mellitus, osteoporosis, renal...

2011-04-01

166

Aryl Acetate Phase Transfer Catalysis: Method and Computation Studies.  

E-print Network

??Brief explanation and history of cinchona based Phase Transfer Catalysis (PTC). Studied aryl acetates in PTC, encompassing napthoyl, 6-methoxy napthoyl, phenyl and protected 4-hydroxy phenyl… (more)

Binkley, Meisha A

2011-01-01

167

Polypyrrole based strong acid catalyst for acetalization  

NASA Astrophysics Data System (ADS)

Novel polypyrrole based acid catalyst has been synthesized through the neutralization reaction of polypyrrole and sulfuric acid. The polypyrrole based acid owned the acidity as high as 6.0 mmol/g, which was much higher than that of the traditional solid acids such as Nafion and Amberlyst-15 (0.8 mmol/g). The catalytic activities of the novel solid acid were investigated through the acetalization. The results showed that the novel solid acid held high activities for the reactions. Furthermore, the recycled activities of the catalyst indicated that the solid acid owned high stability during the catalytic process and little acid sites dropped from polypyrrole. The high acidity and stability made the novel polypyrrole based acid hold great potential for the green chemical processes.

Liang, Xuezheng; Cheng, Yuxiao; Qi, Chenze

2011-09-01

168

Synthesis and regeneration of lead (IV) acetate  

SciTech Connect

Lead acetate [Pb(O{sub 2}CMe){sub 4}] was easily synthesized from a warm solution of Pb{sub 3}O{sub 4}, HO{sub 2}CMe and O(OCMe){sub 2} following literature preparations when the appropriate measures to minimize water contamination were followed. Furthermore, Pb(O{sub 2}CMe){sub 4} which has been decomposed (evidenced by the appearance of a purple color due to oxidation) can be regenerated using a similar preparatory route. Introduction of Pb(O{sub 2}CMe){sub 4} from the two routes outlined above into the IMO process for production of PZT thin films gave films with comparable ferroelectric properties to commercially available Pb(O{sub 2}CMe){sub 4} precursors. However, the freshly synthesized material yields PZT films with better properties compared to the recycled material.

Boyle, T.J.; Al-Shareef, H.N.; Moore, G.J. [Sandia National Labs., Albuquerque, NM (United States). Advanced Materials Lab.

1996-11-01

169

DEOXYRIBONUCLEIC ACID HYBRIDS OF ACETIC ACID BACTERIA  

PubMed Central

De Ley, J. (State University, Ghent, Belgium), and S. Friedman. Deoxyribonucleic acid hybrids of acetic acid bacteria. J. Bacteriol. 88:937–945. 1964.—Deuterated N15-labeled deoxyribonucleic acid (DNA) from Acetobacter aceti (mesoxydans 4) forms hybrids with ordinary DNA from other species of this genus (A. xylinum, A. pasteurianus, A. estunensis, and possibly A. xylinoides) when the guanine plus cytosine base composition does not vary by more than 1 to 2%. Beyond this limit (A. aceti Ch31 and A. muciparus 5) no hybrids are formed. The hybrids are apparently derived from an asymmetrical part of the compositional distribution. The results lend strength to the concept of a genetic species rather than to a division of a genus into sharply separated species, based on small phenotypic differences. Taxonomic implications are discussed. PMID:14219057

De Ley, J.; Friedman, S.

1964-01-01

170

Role of apoptosis in uranyl acetate-induced acute renal failure and acquired resistance to uranyl acetate  

Microsoft Academic Search

Role of apoptosis in uranyl acetate-induced acute renal failure and acquired resistance to uranyl acetate.BackgroundWe have previously reported that animals recovering from uranyl acetate (UA)-induced acute renal failure (ARF) were resistant to subsequent insult. Recent evidence suggests that apoptosis participates in tubular damage. We investigated the role of apoptosis in UA-induced ARF and attenuation of ARF in acquired resistance to

Koji Sano; Yoshihide Fujigaki; Takehiko Miyaji; Naoki Ikegaya; Kazuhisa Ohishi; Katsuhiko Yonemura; Akira Hishida

2000-01-01

171

Phase and reaction equilibria of acetic acid–1-pentanol–water– n-amyl acetate system at 760 mm Hg  

Microsoft Academic Search

The esterification reaction of acetic acid and alcohol is one of the processes applying reactive distillation technology. It is known that the thermodynamic properties are essential to chemical process design. In this study, the thermodynamic behaviors of vapor–liquid equilibrium (VLE) and reaction equilibrium of acetic acid, 1-pentanol, n-amyl acetate, and water mixture were determined experimentally. Since the present esterification reaction

Liang-sun Lee; Shen-jang Liang

1998-01-01

172

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

NASA Technical Reports Server (NTRS)

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

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

1988-01-01

173

Thermal decomposition of pyridine-substituted cobaltic acetate in acetic acid.  

PubMed

The thermal decomposition of [py(3)Co(3)O(OAc)(5)OH][PF(6)] in acetic acid solution in the absence of oxygen produced carbon dioxide, methane, carbon monoxide, picoline, and formic acid as the major products. The ratio of the products was affected by the water concentration and acidity of the mixture. Increased water concentration caused a decrease in methane and an increase in carbon monoxide. Decreased acidity resulted in an increase in methane and a decrease in carbon monoxide. Isotopic labeling experiments showed that some of the carbon monoxide originated as the carboxyl group of the acetic acid. Labeling experiments also showed that formaldehyde and formic acid could be converted to carbon monoxide under the reaction conditions. Two pathways leading to the formation of carbon monoxide were proposed; one involving the decomposition of glyoxylic acid and another involving the oxidation of the methyl radical by cobalt(III). PMID:20397646

Sumner, Charles E; Little, James; Howard, Adam S; Liang, Weimin C

2010-05-17

174

Theoretical studies of molecular structure and vibrational spectra of melaminium acetate acetic acid solvate monohydrate.  

PubMed

The molecular geometry and vibrational frequencies of melaminium acetate acetic acid solvate monohydrate in the ground state have been calculated by using the Hartree-Fock (HF) and density functional method (B3LYP) with 6-31++G(d,p) basis set. The results of the optimized molecular structure are presented and compared with the experimental X-ray diffraction. The molecule contains the weak hydrogen bonds of N-H...O and O-H...O types, and those bonds are calculated with HF and DFT method. The computed vibrational frequencies were used to determine the types of molecular motions associated with each of the experimental bands observed. In addition, calculated results are related to the linear correlation plot of computed data versus experimental geometric parameters and IR data. PMID:20692201

Pekparlak, A; Avci, D; Cömert, H; Atalay, Y

2010-10-15

175

Origin and fate of acetate in an acidic fen.  

PubMed

Acetate is a central intermediate in the anaerobic degradation of organic matter, and the resolution of its metabolism necessitates integrated strategies. This study aims to (1) estimate the contribution of acetogenesis to acetate formation in an acidic fen (pH ~ 4.9), (2) assess the genetic potential for acetogenesis targeting the fhs gene encoding formyltetrahydrofolate synthetase (FTHFS) and (3) unravel the in situ turnover of acetate using stable carbon isotope pore-water analysis. H(2)/CO(2)-supplemented peat microcosms yielded (13)C-depleted acetate (-37.2‰ vs. VPDB (Vienna Peedee belemnite standard) compared with -14.2‰ vs. VPDB in an unamended control), indicating the potential for H(2)-dependent acetogenesis. Molecular analysis revealed a high diversity and depth-dependent distribution of fhs phylotypes with the highest number of operational taxonomic units in 0-20 cm depth, but only few and distant relationships to known acetogens. In pore waters, acetate concentrations (0-170 ?M) and ?(13)C-values varied widely (-17.4‰ to -3.4‰ vs. VPDB) and did not indicate acetogenesis, but pointed to a predominance of sinks, which preferentially consumed (12)C-acetate, like acetoclastic methanogenesis. However, depth profiles of methane and ?(13)C(CH4) revealed a temporarily and spatially restricted role of this acetate sink and suggest other processes like sulfate and iron reduction played an important role in acetate turnover. PMID:22404042

Hädrich, Anke; Heuer, Verena B; Herrmann, Martina; Hinrichs, Kai-Uwe; Küsel, Kirsten

2012-08-01

176

Cyclization of ?-terpenols and their acetates by fluorosulfonic acid  

Microsoft Academic Search

It has been shown that the superacid cyclization of ?-terpenols and their acetates takes place with structural selectivity\\u000a and chemo- and stereospecificity and leads to cyclic isoprenoids with higher yields than the cyclization of the corresponding\\u000a ?-terpenols and their acetates.

N. D. Ungur; N. P. Popa; Nguen Van Tuen; P. F. Vlad

1993-01-01

177

Addition of acetic acid to styrene catalyzed by ion exchanger  

Microsoft Academic Search

The possibility of preparation of 1-phenylethyl acetate by direct addition of acetic acid to styrene catalyzed by Ostion KS in the acid cycle has been investigated. The reaction is accompanied by the formation of higher molecular compounds. The effect of temperature, mole ratio of the starting compounds, stabilization of styrene, amount of the catalyst and of its repeated use on

L. ?ervený; A. Marhoul; J. Kozel

1988-01-01

178

Interaction between acetate fed sulfate reducers and methanogens  

Microsoft Academic Search

During anaerobic treatment of sulfate containing wastewaters, sulfate reducing bacteria (SRB) and methane producing bacteria (MPB) can compete for acetate as the common primary substrate. Since acetate is an intermediate of anaerobic degradation of complex wastes, the outcome of the competition between SRB and MPB can affect the treatment efficiency. The objective of this research was to determine the effects

S. K. Bhattacharya; V. Uberoi; M. M. Dronamraju

1996-01-01

179

Uptake and turnover of acetate in hypersaline environments  

Microsoft Academic Search

Acetate uptake and turnover rates were determined for the heterotrophic community in hypersaline environments (saltern crystallizer ponds, the Dead Sea) dominated by halpphilic Archaea. Acetate was formed from glycerol, which is potentially the major available carbon source for natural communities of halophilic Archaea. Values of [Kt + Sn] (the sum of the substrate affinity and the substrate concentration present in

Aharon Oren

1995-01-01

180

Characterization of acetic acid bacteria in “traditional balsamic vinegar”  

Microsoft Academic Search

This study evaluated the glucose tolerance of acetic acid bacteria strains isolated from Traditional Balsamic Vinegar. The results showed that the greatest hurdle to acetic acid bacteria growth is the high sugar concentration, since the majority of the isolated strains are inhibited by 25% of glucose. Sugar tolerance is an important technological trait because Traditional Balsamic Vinegar is made with

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

2006-01-01

181

Cellulose production by acetic acid-resistant Acetobacter xylinum  

Microsoft Academic Search

A bacterium that could produce a gelatinous cellulosic pellicle in the presence of more than 2% acetic acid was isolated as a contaminant in a continuous surface culture for acetic acid production using Acetobacter aceti. The bacterium was identified as a strain belonging to Acetobacter xylinum and designated as strain DA. The production of cellulose in a static culture of

Kiyoshi Toda; Tomoko Asakura; Masahiro Fukaya; Etsuzo Entani; Yoshiya Kawamura

1997-01-01

182

Transition-Metal-Catalyzed Carbonylation of Methyl Acetate.  

ERIC Educational Resources Information Center

Presents a study of the rhodium-catalyzed, ioding-promoted carbonylation of methyl acetate. This study provides an interesting contrast between the carbonylation of methyl acetate and the carbonylation of methanol when similar rhodium/iodine catalyst systems are used. (JN)

Polichnowski, S. W.

1986-01-01

183

Dynamical characterization of a cellulose acetate polysaccharide.  

PubMed

This work brings together dynamical and structural information at a molecular level for cellulose acetate being an original contribution to the general description of polysaccharide properties. In particular, it allowed reinterpreting the secondary relaxation mechanisms that are still controversial in the literature; a compilation of data provided by different authors is provided. Detailed dynamical information is provided by dielectric relaxation spectroscopy (DRS) (10(-1)-10(6) Hz) for cellulose acetate (CA) in the sub-T(g) region below ambient temperature; results were compared with cellulose acetate structured as an asymmetric membrane (CAmb). In samples with low water content, two secondary relaxation processes between 173 and 298 K were identified by DRS, associated with localized mobility. The process located at the lowest temperatures (process I) has a different mobility in CA relative to CAmb. The identical crystalline/amorphous state of both materials allowed rationalizing the distinct behavior in terms of polymeric arrangement and ability for water uptake. The looser structure of the CA relative to CAmb as confirmed by FTIR, TGA, and DSC analysis makes more sites accessible to water molecules, resulting in a higher water retention in CA (2.73% w/w) relative to CAmb (1.60% w/w) and an increased molecular mobility in the former due to a plasticizing effect. In both materials, process I is significantly influenced by hydration, shifting to higher frequencies and lower temperatures upon water uptake. This process seems to be associated with mobility occurring within the monomeric unit, which embraces the two anhydroglucose rings connected by the glycosidic linkage and the polar groups directly attached to it. It should involve a very limited length scale, as suggested by its location, far below the glass transition, and the tau(infinity) value with a low entropic effect. The relaxation process that emerges later, process II, is similar for both samples being much less influenced by water but experiencing a slight antiplasticizing effect shifting to lower frequencies and higher temperatures upon hydration. It should involve side group motions, strongly coupled to the mobility of the anhydroglucose rings, which become hindered probably due to establishment of H-bonds with water molecules. The plasticizing/antiplasticizing effect is being discussed only on the basis of the frequency position of the relaxation peak. Processes I and II merge into a broad relaxation (gamma(dry)) upon water removal in both CA and CAmb, however evolving slower in the former with drying, due to a more disordered structure of CA that allows water to interact with more internal sites in the polymer. At higher temperatures (T > or = 353 K), a process emerges in the high frequency side of the dynamic alpha-relaxation which is compatible with a beta(JG)-relaxation. The structured specimen CAmb provided an additional way to probe the morphological changes undergone by the material when annealed to temperatures higher than 353 K, originating an increase in the dielectric response. This effect can be associated with a skin densification and partial collapse of the membrane porous network, as observed by SEM. PMID:20690651

Sousa, Miriam; Brás, Ana Rita; Veiga, Helena Isabel M; Ferreira, Frederico Castelo; de Pinho, Maria Norberta; Correia, Natália T; Dionísio, Madalena

2010-09-01

184

Acetate addition to an immobilized yeast column for ethanol production  

SciTech Connect

Acetate, a by-product of ethanol fermentation by Saccharomyces cerevisiae, has been shown to inhibit cell growth if present in high concentrations. Consequently, acetate has been considered undesirable in systems where the production rate depends upon steady-state growth. Acetate, however, may be desirable in some systems since it increases the specific rate of ethanol production by increasing the maintenance requirements of the yeast. In immobilized cell reactors using crosslinking method, steady state is not achieved and cell overgrowth is a problem. This article presents the results of a study aimed at taking advantage of the use of acetate, both to reduce cell overgrowth and increase productivity. Various concentrations of acetate were added to batch and plug flow systems, while monitoring the effects on cell growth and ethanol production. The productivity was increased by as much as 50% in an immobilized cell reactor (ICR), while cell growth was greatly reduced. 19 references.

Vega, J.L.; Clausen, E.C.; Gaddy, J.L.

1987-03-01

185

Glycerol acetals as anti-freezing additives for biodiesel.  

PubMed

Glycerol acetals from butanal, pentanal, hexanal, octanal and decanal were prepared with the use of Amberlyst-15 acid resin as catalyst. The glycerol conversion decreases with the size of the hydrocarbon chain. This fact has been associated with formation of micelles and aggregates of the aldehyde to minimize the interaction between the polar glycerol molecule with the hydrocarbon chain. The Z+E mixture of the acetals with five and six-member rings were produced in all cases. The distribution of the acetal isomers varied with the reaction time, especially for the long chain aldehydes. Addition of 5 vol.% of the butanal-glycerol acetal reduced the pour point of animal fat biodiesel (methyl ester) from 18 to 13 degrees C. The decrease in the pour point of the glycerol acetals-biodiesel mixtures were dependent on the size of the hydrocarbon chain and the percent blended. PMID:20304633

Silva, Paulo H R; Gonçalves, Valter L C; Mota, Claudio J A

2010-08-01

186

The clinical use of PET with 11C-acetate  

PubMed Central

The aim of this review is to evaluate clinical applications of 11C-acetate positron emission tomography (PET). Acetate is quickly metabolized into acetyl-CoA in human cells. In this form it can either enter into the tricarboxylic acid cycle, thus producing energy, as happens in the myocardium, or participate in cell membrane lipid synthesis, as happens in tumor cells. 11C-acetate PET was originally employed in cardiology, to study myocardial oxygen metabolism. More recently it has also been used to evaluate myocardial perfusion, as well as in oncology. The first studies of 11C-acetate focused on its use in prostate cancer. Subsequently, 11C-acetate was studied in other urological malignancies, as well as renal cell carcinoma and bladder cancer. Well differentiated hepatocellular carcinoma represents an 18F-fluoro-deoxyglucose (18F-FDG) PET pitfall, so many authors have proposed to use 11C-acetate in addition to 18F-FDG in studying this tumor. 11C-acetate PET has also been used in other malignancies, such as brain tumors and lung carcinoma. Some authors reported a few cases in which 11C-acetate PET incidentally found multiple myeloma or rare tumors, such as thymoma, multicentric angiomyolipoma of the kidney and cerebellopontine angle schwannoma. Lastly, 11C-acetate PET was also employed in a differential diagnosis case between glioma and encephalitis. The numerous studies on 11C-acetate have demonstrated that it can be used in cardiology and oncology with no contraindications apart from pregnancy and the necessity of a rapid scan. Despite its limited availability, this tracer can surely be considered to be a promising one, because of its versatility and capacity to even detect non 18F-FDG-avid neoplasm, such as differentiated lung cancer or hepatocellular carcinoma. PMID:23133801

Grassi, Ilaria; Nanni, Cristina; Allegri, Vincenzo; Morigi, Joshua James; Montini, Gian Carlo; Castellucci, Paolo; Fanti, Stefano

2012-01-01

187

Polyvinyl acetate-based film coatings.  

PubMed

Polyvinyl acetate-based colloidal aqueous polymer dispersion Kollicoat(®) SR 30 D results in coatings characterized by moderate swelling behaviour, lipophilicity, pH-independent permeability for actives and high flexibility to withstand mechanical stress and is therefore used for controlled release coating. The colloidal aqueous polymer dispersion of Kollicoat(®) SR 30 D can be easily processed due to an optimal low minimum film forming temperature (MFT) of 18 °C without plasticizer addition and a thermal after-treatment (curing) of coated pellets. The drug release from Kollicoat(®) SR 30 D coated pellets was almost pH independent. Drug release could be easily adjusted by coating level or addition of soluble pore forming polymers. Physically stable Kollicoat(®) SR 30 D dispersions were obtained with the water-soluble polymers Kollidon(®) 30 and Kollicoat(®) IR up to 50% w/w. The addition of only 10% w/w triethyl citrate as plasticizer improved the flexibility of the films significantly and allowed compaction of the pellets. The drug release was almost independent of the compression force and the pellet content of the tablets. The inclusion of various tableting excipients slightly affected the drug release, primarily because of a different disintegration rate of the tablets. A combination of Kollicoat(®) SR 30 D and Kollicoat(®) IR with higher coating levels>10 mg/cm(2) is a relatively new alternative to OROS system which does not require drilling. PMID:24076229

Kolter, K; Dashevsky, A; Irfan, Muhamad; Bodmeier, R

2013-12-01

188

Pharmacokinetics and drug interactions of eslicarbazepine acetate.  

PubMed

Eslicarbazepine acetate (ESL) is a novel once-daily antiepileptic drug (AED) approved in Europe since 2009 that was found to be efficacious and well tolerated in a phase III clinical program in adult patients with partial onset seizures previously not controlled with treatment with one to three AEDs, including carbamazepine (CBZ). ESL shares with CBZ and oxcarbazepine (OXC) the dibenzazepine nucleus bearing the 5-carboxamide substitute, but is structurally different at the 10,11 position. This molecular variation results in differences in metabolism, preventing the formation of toxic epoxide metabolites such as carbamazepine-10,11-epoxide. Unlike OXC, which is metabolized to both eslicarbazepine and (R)-licarbazepine, ESL is extensively converted to eslicarbazepine. The systemic exposure to eslicarbazepine after ESL oral administration is approximately 94% of the parent dose, with minimal exposure to (R)-licarbazepine and OXC. After ESL oral administration, the effective half-life (t(1/2,eff) ) of eslicarbazepine was 20-24 h, which is approximately two times longer than its terminal half-life (t(1/2)). At clinically relevant doses (400-1,600 mg/day) ESL has linear pharmacokinetics (PK) with no effects of gender or moderate liver impairment. However, because eslicarbazepine is eliminated primarily (66%) by renal excretion, dose adjustment is recommended for patients with renal impairment. Eslicarbazepine clearance is induced by phenobarbital, phenytoin, and CBZ and it dose-dependently decreases plasma exposure of oral contraceptive and simvastatin. PMID:22612290

Bialer, Meir; Soares-da-Silva, Patricio

2012-06-01

189

UVB photolysis of hydrocortisone 21-acetate.  

PubMed

Hydrocortisone 21-acetate (HCA) in methanol solution undergoes photodegradation under UVB light, as monitored by HPLC. Five main photoproducts have been isolated and characterized by means of NMR and mass spectroscopy. One of them derives from a Norrish I photoreaction which cleaves the C17-C20 bond of the steroid yielding the andro-derivative, a second product comes from a Yang-type photorearrangement which links C18 to C20 yielding a cyclobutane adduct. The former photoproduct, in turn, undergoes further photolysis giving rise to various photoproducts, of which three have been characterized. The first is a stereoisomer of the andro-derivative, the others arise from the opening of the five-membered ring. HCA also proved photounstable in the solid state and in a commercial formulation for topical use, thus confirming the requirements of the Pharmacopeias for light protection of this drug. Indeed, experiments on LPS-stimulated THP-1 cells demonstrated the loss of anti-inflammatory activity when HCA was UVB-photodegraded. The radical mechanism involved in HCA photolysis seems also responsible for the in vitro photohemolytic effect and lipid peroxidation induced by HCA in combination with UVB light. PMID:18423938

Caffieri, Sergio; Dall'Acqua, Stefano; Castagliuolo, Ignazio; Brun, Paola; Miolo, Giorgia

2008-08-01

190

76 FR 32366 - Determination That ORLAAM (Levomethadyl Acetate Hydrochloride) Oral Solution, 10 Milligrams...  

Federal Register 2010, 2011, 2012, 2013

...Levomethadyl Acetate Hydrochloride) Oral Solution, 10 Milligrams/Milliliter, Was Not...acetate hydrochloride (HCl)) oral solution, 10 milligrams (mg)/milliliter...ANDAs) for levomethadyl acetate HCl oral solution, 10 mg/mL, if all other legal...

2011-06-06

191

Water dispersible microbicidal cellulose acetate phthalate film  

PubMed Central

Background Cellulose acetate phthalate (CAP) has been used for several decades in the pharmaceutical industry for enteric film coating of oral tablets and capsules. Micronized CAP, available commercially as "Aquateric" and containing additional ingredients required for micronization, used for tablet coating from water dispersions, was shown to adsorb and inactivate the human immunodeficiency virus (HIV-1), herpesviruses (HSV) and other sexually transmitted disease (STD) pathogens. Earlier studies indicate that a gel formulation of micronized CAP has a potential as a topical microbicide for prevention of STDs including the acquired immunodeficiency syndrome (AIDS). The objective of endeavors described here was to develop a water dispersible CAP film amenable to inexpensive industrial mass production. Methods CAP and hydroxypropyl cellulose (HPC) were dissolved in different organic solvent mixtures, poured into dishes, and the solvents evaporated. Graded quantities of a resulting selected film were mixed for 5 min at 37°C with HIV-1, HSV and other STD pathogens, respectively. Residual infectivity of the treated viruses and bacteria was determined. Results The prerequisites for producing CAP films which are soft, flexible and dispersible in water, resulting in smooth gels, are combining CAP with HPC (other cellulose derivatives are unsuitable), and casting from organic solvent mixtures containing ?50 to ?65% ethanol (EtOH). The films are ?100 µ thick and have a textured surface with alternating protrusions and depressions revealed by scanning electron microscopy. The films, before complete conversion into a gel, rapidly inactivated HIV-1 and HSV and reduced the infectivity of non-viral STD pathogens >1,000-fold. Conclusions Soft pliable CAP-HPC composite films can be generated by casting from organic solvent mixtures containing EtOH. The films rapidly reduce the infectivity of several STD pathogens, including HIV-1. They are converted into gels and thus do not have to be removed following application and use. In addition to their potential as topical microbicides, the films have promise for mucosal delivery of pharmaceuticals other than CAP. PMID:14617380

Neurath, A Robert; Strick, Nathan; Li, Yun-Yao

2003-01-01

192

Clostridiumm ljungdahlii, an anaerobic ethanol and acetate producing microorganism  

DOEpatents

A newly discovered microorganism was isolated in a biologically pure culture and designated Clostridium ljungdahlii, having the identifying characteristics of ATCC No. 49587. Cultured in an aqueous nutrient medium under anaerobic conditions, this microorganism is capable of producing ethanol and acetate from CO and H.sub.2 O and/or CO.sub.2 and H.sub.2 in synthesis gas. Under optimal growth conditions, the microorganism produces acetate in preference to ethanol. Conversely, under non-growth conditions, ethanol production is favored over acetate.

Gaddy, James L. (Fayetteville, AR); Clausen, Edgar C. (Fayetteville, AR)

1992-01-01

193

The medical and metabolic consequences of administration of sodium acetate.  

PubMed

1. The standard total parenteral nutrition, peritoneal dialysis, hemodialysis and many surgical fluids in use today contain 36 to 45 mM D,L-lactate or 2 to 140 mM acetate whereas the normal blood level of D-lactate is 0.02 mM L-lactate 0.5 to 5 mM and acetate 0.1 nM. The reasons for the continued use in patients of such unphysiological concentrations of these anions appear to be historic. 2. Administration of similar concentrations of these anions to the rat causes widespread metabolic disturbances which mimic many of the untoward complications associated with current parenteral and dialysis therapy. Understanding of the mechanisms attendant upon the metabolism of these anions may serve as a guide for designing improved parenteral fluids for human patients. 3. Elevation of blood D-lactate to 5 mM is associated with cerebral dysfunction in human patients. 4. Acetate stimulates the release of the inflammatory leukokine, interleukin-1 from human monocytes. Use of 35 to 45 mM acetate in peritoneal dialysis fluids led to peritoneal fibrosis. Patients exposed to acetate containing hemodialysis fluids have 12-fold elevation in their plasma interleukin-1 levels. 5. Administration of 20 mM sodium acetate to rats leads to a number of metabolic disturbances similar to those seen in human dialysis patients: (a) Acetate elevates blood glucose in the rat and may contribute to the exacerbation of the carbohydrate intolerance seen in uremic patients. (b) Acetate increases the levels of hepatic malonyl CoA, the rate controlling substrate of fatty acid synthesis and may exacerbate the hypertriglyceridemia characteristic of dialysis patients. (c) Acetate administration in the rat leads to a decrease in the cytosolic phosphorylation potential, reduction of the redox state of the free cytosolic NAD couple and paradoxical oxidation of the mitochondrial NAD couple in a pattern analogous to that produced by uncouplers of oxidative phosphorylation and may account in part for the elevation of temperature reported in patients undergoing hemodialysis with acetate. (d) Acetate administration in the rat leads to an increase in intracellular phosphorylated intermediates, adenine nucleotides, inorganic phosphate, inorganic pyrophosphate, calcium and magnesium. On cessation of acetate metabolism, the inorganic phosphate and calcium accumulated intracellularly leave the intracellular space. In patients undergoing hemodialysis, the blood phosphate returns to predialysis levels, within 6 hr after the completion of treatment, leaving significant numbers of patients with chronic hyperphosphatemia and the multiple complications attendant to that state.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:2854950

Veech, R L; Gitomer, W L

1988-01-01

194

The antibacterial activity and stability of acetic acid.  

PubMed

Acetic acid has been shown to have good antibacterial activity against micro-organisms such as Pseudomonas aeruginosa. This study examined the activity against a range of bacterial pathogens and also assessed any reduction in antibacterial activity due to evaporation or inactivation by organic material in dressings. Acetic acid was active at dilutions as low as 0.166% and the activity was not reduced by evaporation nor by inactivation by cotton swabs. Burn injuries are a major problem in countries with limited resources. Acetic acid is an ideal candidate for use in patients who are treated in those parts of the world. PMID:23747099

Fraise, A P; Wilkinson, M A C; Bradley, C R; Oppenheim, B; Moiemen, N

2013-08-01

195

The twinned crystal structure of mu-2,2'-bipyrimidine-1kappa2N1,N1':2kappa2N3,N3'-bis{tris[4,4,4-trifluoro-1-(2-thienyl)butane-1,3-dionato-kappa2O,O']terbium(III)} ethyl acetate solvate.  

PubMed

The title compound, [Tb2(C24H12F9O6S3)2(C8H6N4)].C4H8O2, has two terbium(III) centers bridged by the polyazine ligand 2,2'-bipyrimidine (bpm), which is distorted from planarity by 7.0 (2) degrees . The terminal ligand 4,4,4-trifluoro-1-(2-thienyl)butane-1,3-dione (tta) is bidentate, coordinating through the two O atoms, while the bridging ligand is bis-bidentate, coordinating through four equivalent N atoms. Both the complex and the ethyl acetate solvent molecules are disordered. The structure was refined as a non-merohedral twin. PMID:16679578

Kirschbaum, Kristin; Fratini, Albert; Swavey, Shawn

2006-05-01

196

Cosolvent gel-like materials from partially hydrolyzed poly(vinyl acetate)s and borax.  

PubMed

A gel-like, high-viscosity polymeric dispersion (HVPD) based on cross-linked borate, partially hydrolyzed poly(vinyl acetate) (xPVAc, where x is the percent hydrolysis) is described. Unlike hydro-HVPDs prepared from poly(vinyl alcohol) (PVA) and borate, the liquid portion of these materials can be composed of up to 75% of an organic cosolvent because of the influence of residual acetate groups on the polymer backbone. The effects of the degree of hydrolysis, molecular weight, polymer and cross-linker concentrations, and type and amount of organic cosolvent on the rheological and structural properties of the materials are investigated. The stability of the systems is explored through rheological and melting-range studies. (11)B NMR and small-angle neutron scattering (SANS) are used to probe the structure of the dispersions. The addition of an organic liquid to the xPVAc-borate HVPDs results in a drastic increase in the number of cross-linked borate species as well as the agglomeration of the polymer into bundles. These effects result in an increase in the relaxation time and thermal stability of the networks. The ability to make xPVAc-borate HVPDs with very large amounts of and rather different organic liquids, with very different rheological properties that can be controlled easily, opens new possibilities for applications of PVAc-based dispersions. PMID:21848256

Angelova, Lora V; Terech, Pierre; Natali, Irene; Dei, Luigi; Carretti, Emiliano; Weiss, Richard G

2011-09-20

197

21 CFR 524.1881 - Prednisolone acetate ophthalmic and topical dosage forms.  

Code of Federal Regulations, 2010 CFR

...Prednisolone acetate ophthalmic and topical dosage forms. 524.1881 Section...RELATED PRODUCTS OPHTHALMIC AND TOPICAL DOSAGE FORM NEW ANIMAL DRUGS ...Prednisolone acetate ophthalmic and topical dosage...

2010-04-01

198

Expedient synthesis of ?-(2-azaheteroaryl) acetates via the addition of silyl ketene acetals to azine-N-oxides.  

PubMed

A new and expedient synthesis of ?-(2-azaheteroaryl) acetates is presented. The reaction proceeds rapidly under mild conditions via the addition of silyl ketene acetals to azine-N-oxides in the presence of the phosphonium salt PyBroP. This procedure affords diverse ?-(2-azaheteroaryl) acetates which are highly desirable components/building blocks in molecules of pharmaceutical interest but are traditionally challenging to synthesize via contemporary methods. The reaction optimization and mechanism as well as a novel electronically enhanced PyBroP derivative are described. PMID:24885646

Londregan, Allyn T; Burford, Kristen; Conn, Edward L; Hesp, Kevin D

2014-06-20

199

40 CFR 721.3880 - Polyalkylene glycol substituted acetate.  

Code of Federal Regulations, 2010 CFR

...Significant New Uses for Specific Chemical Substances § 721.3880...substituted acetate. (a) Chemical substance and significant...to reporting. (1) The chemical substance identified generically...substance without providing risk notification as...

2010-07-01

200

A PROGESTOGEN (CHLORMADINONE ACETATE = CAP) FOR CYCLE CONTROL AND INFERTILITY  

E-print Network

A PROGESTOGEN (CHLORMADINONE ACETATE = CAP) FOR CYCLE CONTROL AND INFERTILITY TREATMENT IN THE MARE, CAP has been used for infertility treatments and cycle control in mares in Austria. In all indications

Paris-Sud XI, Université de

201

SOLVENT EXTRACTION OF WASTEWATERS FROM ACETIC-ACID MANUFACTURE  

EPA Science Inventory

Solvent extraction was evaluated as a potential treatment method for wastewaters generated during the manufacture of acetic acid. Possible goals for an extraction process were considered. For the wastewater samples studied, extraction appeared to be too expensive to be practical ...

202

Health and environmental effects profile for 2-methoxyethanol acetate  

SciTech Connect

The Health and Environmental Effects Profile for 2-methoxyethanol acetate was prepared to support listings of hazardous constituents of a wide range of waste streams under Section 3001 of the Resource Conservation and Recovery Act (RCRA) and to provide health-related limits for emergency actions under Section 101 of the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA). Both published literature and information obtained from Agency program office files were evaluated as they pertained to potential human-health, aquatic-life and environmental effects of hazardous-waste constituents. 2-methoxyethanol acetate has been determined to be a systemic toxicant. The daily exposure to the human population (including sensitive subgroups) that is likely to be without appreciable risk of deleterious effect during a lifetime, for 2-methoxyethanol acetate is 0.002 mg/kg/day for inhalation exposure. The Reportable Quantity (RQ) value for 2-methoxyethanol acetate is 100.

Not Available

1987-04-01

203

Acetate-Dependent Mechanisms of Inborn Tolerance to Ethanol  

PubMed Central

Aims: To clarify the role of acetate in neurochemical mechanisms of the initial (inborn) tolerance to ethanol. Methods: Rats with low and high inborn tolerance to hypnotic effect of ethanol were used. In the brain region homogenates (frontal and parietal cortex, hypothalamus, striatum, medulla oblongata) and brain cortex synaptosomes, the levels of acetate, acetyl-CoA, acetylcholine (AcH), the activity of pyruvate dehydrogenase (PDG) and acetyl-CoA synthetase were examined. Results: It has been found that brain cortex of rats with high tolerance to hypnotic effect of ethanol have higher level of acetate and activity of acetyl-CoA synthetase, but lower level of acetyl-?CoA and activity of PDG. In brain cortex synaptosomes of tolerant rats, the pyruvate oxidation rate as well as the content of acetyl-CoA and AcH synthesis were lower when compared with intolerant animals. The addition of acetate into the medium significantly increased the AcH synthesis in synaptosomes of tolerant, but not of intolerant animals. Calcium ions stimulated the AcH release from synaptosomes twice as high in tolerant as in intolerant animals. Acetate eliminated the stimulating effect of calcium ions upon the release of AcH in synaptosomes of intolerant rats, but not in tolerant animals. As a result, the quantum release of AcH from synaptosomes in the presence of acetate was 6.5 times higher in tolerant when compared with intolerant rats. Conclusion: The brain cortex of rats with high inborn tolerance to hypnotic effect of ethanol can better utilize acetate for the acetyl-CoA and AcH synthesis, as well as being resistant to inhibitory effect of acetate to calcium-stimulated release of AcH. It indicates the metabolic and cholinergic mechanisms of the initial tolerance to ethanol. PMID:21349883

Zimatkin, Sergey M.; Oganesian, Nikolay A.; Kiselevski, Yury V.; Deitrich, Richard A.

2011-01-01

204

Existence of a Novel Liguid Phase in Methyl Acetate  

Microsoft Academic Search

For methyl acetate with a planar structure \\\\includegraphics{dummy.eps} in the molecule, a spin-lattice relaxation time (T1) and a specific volume were measured in the liquid phase. Methyl acetate has a liquid-liquid phase transition at -12°C at atmospheric pressure. The liquid phase is divided into two parts named as L1 and L2 corresponding as high and low temperature liquid phase, respectively.

Shunichi Kawanishi

1983-01-01

205

Cathodic Hydrogen Evolution from Aqueous Solutions of Acetic Acid  

Microsoft Academic Search

In continuation of the work on establishing hydrogen donors in the hydrogen evolution reaction from different acid molecules, cathodic evolution of hydrogen on silver is investigated from solutions of monobasic acetic acid with the aim to establish the origin of reduced hydrogen. Solutions of 0.2 M acetic acid with 0.2 M perchloric acid, neutralized to different pH values by NaOH,

V. Marinovi?; A. R. Despi?

2004-01-01

206

METABOLISM OF ACETATE BY SHEEP LIVER HOMOGE'NATES 1  

Microsoft Academic Search

The metabolism of acetate has been studied in sheep liver homogenates. ContraD- to previous reports, acetate was oxidized by fresh liver homogenates, and aeet3,l-CoA was oxidized by both fresh and frozen-stored liver homogenates in the presence of the eofaetors XAI) and earnitine. With these two eofactors, oxidation plateaus after 20-30 rain, unless a 4-ca,'bon TCX cycle acid, such as sueeinate,

E. D. MAYFIELD; AXD B. CONNOR JOHNSON

207

Permeability of cellulose acetate membranes to selected solutes  

Microsoft Academic Search

The permeability of cellulose 2.5-acetate films to several electrolytes and nonelectrolytes was measured. Permeabilities were determined by a desorption-rate method in which diffusion and distribution coefficients were measured. The rejection of the same solutes by modified cellulose acetate membranes in reverse osmosis experiments was also measured. A comparison was made between intrinsic water and solute permeabilities and the reverse osmosis

H. K. Lonsdale; B. P. Cross; F. M. Graber; C. E. Milstead

1971-01-01

208

Acetalization of Carbonyl Compounds Catalyzed by I2-Doped Polyaniline  

Microsoft Academic Search

Polyaniline-I2 is prepared by doping of polyaniline base with iodine. Polyaniline base and polyaniline-I2 are characterized by infrared spectra, X-ray diffraction spectra, and thermogravimetric analysis. Polyaniline-I2 is used as a catalyst for the first time in acetalization of carbonyl compounds. The catalyzing acetalization of cyclohexanone and propane-1,2-diol is conducted in excellent yields with simple and more environmental benign procedure. This

Genxiang Luo; Miao He; Zhaojin Zhong

2008-01-01

209

Bacterial utilization of formic and acetic acid in rainwater  

NASA Astrophysics Data System (ADS)

Rain samples were collected aseptically, during 1983 and 1984, in Charlottesville, Virginia to determine the ability of bacteria in precipitation to utilize formate and acetate. The total number of bacteria, as counted by Acridine Orange Direct Counts, was one to two orders of magnitude greater from April to September (10 5 cells ml -1) than during the rest of the year (10 3-10 4 cells ml -1). Formate and acetate concentrations ranged between 6-23 and 3-9 ?M, respectively and were higher from June to September. Heterotrophic uptake on the day of collection was not different from the controls, but after incubation at room temperature for a minimum of three days, the turnover rate constants were 0.14 and 0.17 h -1 for formate and acetate, respectively. Total bacterial counts increased an order of magnitude during that interval. These turnover rate constants were used to calculate losses of 44 and 24 ?moll-1day-1 of formic and acetic acid, respectively. Turnover times were 1.5 and 34 days for formate and acetate, respectively. This study demonstrated that there are viable microorganisms in the atmosphere capable of utilizing formate and acetate for growth.

Herlihy, Linda Jolley; Galloway, James N.; Mills, Aaron L.

210

Proteome analysis of Acetobacter pasteurianus during acetic acid fermentation.  

PubMed

Acetic acid bacteria (AAB) are Gram-negative, strictly aerobic microorganisms that show a unique resistance to ethanol (EtOH) and acetic acid (AcH). Members of the Acetobacter and Gluconacetobacter genera are capable of transforming EtOH into AcH via the alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) enzymes and are used for the industrial production of vinegar. Several mechanisms have been proposed to explain how AAB resist high concentrations of AcH, such as the assimilation of acetate through the tricarboxylic acid (TCA) cycle, the export of acetate by various transporters and modifications of the outer membrane. However, except for a few acetate-specific proteins, little is known about the global proteome responses to AcH. In this study, we used 2D-DIGE to compare the proteome of Acetobacter pasteurianus LMG 1262(T) when growing in glucose or ethanol and in the presence of acetic acid. Interesting protein spots were selected using the ANOVA p-value of 0.05 as threshold and 1.5-fold as the minimal level of differential expression, and a total of 53 proteins were successfully identified. Additionally, the size of AAB was reduced by approximately 30% in length as a consequence of the acidity. A modification in the membrane polysaccharides was also revealed by PATAg specific staining. PMID:22155126

Andrés-Barrao, Cristina; Saad, Maged M; Chappuis, Marie-Louise; Boffa, Mauro; Perret, Xavier; Ortega Pérez, Ruben; Barja, François

2012-03-16

211

Solid–liquid equilibrium in the acetic acid–cyclohexane and acetic acid–trichloroacetic acid systems  

Microsoft Academic Search

Solid–liquid equilibrium in the binary systems acetic acid–cyclohexane and acetic acid–trichloroacetic acid was determined from time–temperature cooling and heating curves. The first system shows an eutectic point at x1?0.08 and T=271.9K. In the second system, a solid compound (1:1) was found and an equilibrium constant of the compound dissociation was calculated.

I Malijevská

2003-01-01

212

Tetrazole acetic acid: tautomers, conformers, and isomerization.  

PubMed

Monomers of (tetrazol-5-yl)-acetic acid (TAA) were obtained by sublimation of the crystalline compound and the resulting vapors were isolated in cryogenic nitrogen matrices at 13 K. The conformational and tautomeric composition of TAA in the matrix was characterized by infrared spectroscopy and vibrational calculations carried out at the B3LYP/6-311++G(d,p) level. TAA may adopt two tautomeric modifications, 1H- and 2H-, depending on the position of the annular hydrogen atom. Two-dimensional potential energy surfaces (PESs) of TAA were theoretically calculated at the MP2/6-311++G(d,p) level, for each tautomer. Four and six symmetry-unique minima were located on these PESs, for 1H- and 2H-TAA, respectively. The energetics of the detected minima was subsequently refined by calculations at the QCISD level. Two 1H- and three 2H-conformers fall within the 0-8 kJ mol(-1) energy range and should be appreciably populated at the sublimation temperature (?330 K). Observation of only one conformer for each tautomer (1ccc and 2pcc) is explained in terms of calculated barriers to conformational rearrangements. All conformers with the cis O=COH moiety are separated by low barriers (less than 10 kJ mol(-1)) and collapse to the most stable 1ccc (1H-) and 2pcc (2H-) forms during deposition of the matrix. On the trans O=COH surfaces, the relative energies are very high (between 12 and 27 kJ mol(-1)). The trans forms are not thermally populated at the sublimation conditions and were not detected in matrices. One high-energy form in each tautomer, 1cct (1H-) and 2pct (2H-), was found to differ from the most stable form only by rotation of the OH group and separated from other forms by high barriers. This opened a perspective for their stabilization in a matrix. 1cct and 2pct were generated in the matrices selectively by means of narrow-band near-infrared (NIR) irradiations of the samples at 6920 and 6937 cm(-1), where the first OH stretching overtone vibrations of 1ccc and 2pcc occur. The reverse transformations could be induced by irradiations at 7010 and 7030 cm(-1), transforming 1cct and 2pct back to 1ccc and 2pcc, also selectively. Besides the NIR-induced transformations, the photogenerated 1cct and 2pct forms also decay in N2 matrices back to 1ccc and 2pcc spontaneously, with characteristic decay times of hours (1H) and tens of minutes (2H). The decay mechanism is rationalized in terms of the proton tunneling. In crystals, TAA exists exclusively as 1H-tautomer. By contrast, the tautomeric composition of the matrix-isolated monomers was found to consist of both 1H- and 2H-tautomers, in comparable amounts. A mechanistic discussion of the tautomerization process occurring during sublimation, accounting also for the observed minor decomposition of TAA leading to CO2 and 5-methyl-tetrazole, is proposed. PMID:24527914

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

2014-02-14

213

Tetrazole acetic acid: Tautomers, conformers, and isomerization  

NASA Astrophysics Data System (ADS)

Monomers of (tetrazol-5-yl)-acetic acid (TAA) were obtained by sublimation of the crystalline compound and the resulting vapors were isolated in cryogenic nitrogen matrices at 13 K. The conformational and tautomeric composition of TAA in the matrix was characterized by infrared spectroscopy and vibrational calculations carried out at the B3LYP/6-311++G(d,p) level. TAA may adopt two tautomeric modifications, 1H- and 2H-, depending on the position of the annular hydrogen atom. Two-dimensional potential energy surfaces (PESs) of TAA were theoretically calculated at the MP2/6-311++G(d,p) level, for each tautomer. Four and six symmetry-unique minima were located on these PESs, for 1H- and 2H-TAA, respectively. The energetics of the detected minima was subsequently refined by calculations at the QCISD level. Two 1H- and three 2H-conformers fall within the 0-8 kJ mol-1 energy range and should be appreciably populated at the sublimation temperature (˜330 K). Observation of only one conformer for each tautomer (1ccc and 2pcc) is explained in terms of calculated barriers to conformational rearrangements. All conformers with the cis O=COH moiety are separated by low barriers (less than 10 kJ mol-1) and collapse to the most stable 1ccc (1H-) and 2pcc (2H-) forms during deposition of the matrix. On the trans O=COH surfaces, the relative energies are very high (between 12 and 27 kJ mol-1). The trans forms are not thermally populated at the sublimation conditions and were not detected in matrices. One high-energy form in each tautomer, 1cct (1H-) and 2pct (2H-), was found to differ from the most stable form only by rotation of the OH group and separated from other forms by high barriers. This opened a perspective for their stabilization in a matrix. 1cct and 2pct were generated in the matrices selectively by means of narrow-band near-infrared (NIR) irradiations of the samples at 6920 and 6937 cm-1, where the first OH stretching overtone vibrations of 1ccc and 2pcc occur. The reverse transformations could be induced by irradiations at 7010 and 7030 cm-1, transforming 1cct and 2pct back to 1ccc and 2pcc, also selectively. Besides the NIR-induced transformations, the photogenerated 1cct and 2pct forms also decay in N2 matrices back to 1ccc and 2pcc spontaneously, with characteristic decay times of hours (1H) and tens of minutes (2H). The decay mechanism is rationalized in terms of the proton tunneling. In crystals, TAA exists exclusively as 1H-tautomer. By contrast, the tautomeric composition of the matrix-isolated monomers was found to consist of both 1H- and 2H-tautomers, in comparable amounts. A mechanistic discussion of the tautomerization process occurring during sublimation, accounting also for the observed minor decomposition of TAA leading to CO2 and 5-methyl-tetrazole, is proposed.

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

2014-02-01

214

Atomic and electronic structure of acetic acid on Ge(100) Do Hwan Kim a,b  

E-print Network

Atomic and electronic structure of acetic acid on Ge(100) Do Hwan Kim a,b , Eunkyung Hwang to investigate the atomic and electronic structure of acetic acid adsorbed on Ge(100) surface. Due to its acidity, acetic acid dissociates and the resulting electron-rich acetate group reacts with the electron

Kim, Sehun

215

values from the non-steady state equation to the steady state at plateaus. The acetate  

E-print Network

values from the non-steady state equation to the steady state at plateaus. The acetate endogenous fluxes did not change during cold acetate infusions of 7 and 14 Ilmol.kg-I.min-I (6 ± 2 et 5 ± 2 pmol the total flux of acetate was higher than 21 1 pmol,kg!',min!' .!. We concluded that the acetate fluxes cal

Boyer, Edmond

216

Zuclopenthixol acetate for acute schizophrenia and similar serious mental illnesses  

PubMed Central

Background Medication used for acute aggression in psychiatry must have rapid onset of effect, low frequency of administration and low levels of adverse effects. Zuclopenthixol acetate is said to have these properties. Objectives To estimate the clinical effects of zuclopenthixol acetate for the management of acute aggression or violence thought to be due to serious mental illnesses, in comparison to other drugs used to treat similar conditions. Search methods We searched the Cochrane Schizophrenia’s Group Trials Register (July 2011). We supplemented this by citation searching and personal contact with authors and relevant pharmaceutical companies. Selection criteria All randomised clinical trials involving people thought to have serious mental illnesses comparing zuclopenthixol acetate with other drugs. Data collection and analysis Two review authors extracted and cross-checked data independently. We calculated fixed-effect relative risks (RR) and 95% confidence intervals (CI) for dichotomous data. We analysed by intention-to-treat. We used mean differences (MD) for continuous variables. Main results We found no data for the primary outcome, tranquillisation. Compared with haloperidol, zuclopenthixol acetate was no more sedating at two hours (n = 40, 1 RCT, RR 0.60, 95% CI 0.27 to 1.34). People given zuclopenthixol acetate were not at reduced risk of being given supplementary antipsychotics (n = 134, 3 RCTs, RR 1.49, 95% CI 0.97 to 2.30) although additional use of benzodiazepines was less (n = 50, 1 RCT, RR 0.03, 95% CI 0.00 to 0.47). People given zuclopenthixol acetate had fewer injections over seven days compared with those allocated to haloperidol IM (n = 70, 1 RCT, RR 0.39, 95% CI 0.18 to 0.84, NNT 4, CI 3 to 14). We found no data on more episodes of aggression or harm to self or others. One trial (n = 148) reported no significant difference in adverse effects for people receiving zuclopenthixol acetate compared with those allocated haloperidol at one, three and six days (RR 0.74, 95% CI 0.43 to 1.27). Compared with haloperidol or clotiapine, people allocated zuclopenthixol did not seem to be at more risk of a range of movement disorders (< 20%). Three studies found no difference in the proportion of people getting blurred vision/dry mouth (n = 192, 2 RCTs, RR at 24 hours 0.90, 95% CI 0.48 to 1.70). Similarly, dizziness was equally infrequent for those allocated zuclopenthixol acetate compared with haloperidol (n = 192, 2 RCTs, RR at 24 hours 1.15, 95% CI 0.46 to 2.88). There was no difference between treatments for leaving the study before completion (n = 522, RR 0.85, 95% CI 0.31 to 2.31). One study reported no difference in adverse effects and outcome scores, when high dose (50-100 mg/injection) zuclopenthixol acetate was compared with low dose (25-50 mg/injection) zuclopenthixol acetate. Authors’ conclusions Recommendations on the use of zuclopenthixol acetate for the management of psychiatric emergencies in preference to ‘standard’ treatment have to be viewed with caution. Most of the small trials present important methodological flaws and findings are poorly reported. This review did not find any suggestion that zuclopenthixol acetate is more or less effective in controlling aggressive acute psychosis, or in preventing adverse effects than intramuscular haloperidol, and neither seemed to have a rapid onset of action. Use of zuclopenthixol acetate may result in less numerous coercive injections and low doses of the drug may be as effective as higher doses. Well-conducted pragmatic randomised controlled trials are needed. PMID:22513898

Jayakody, Kaushadh; Gibson, Roger Carl; Kumar, Ajit; Gunadasa, Shalmini

2014-01-01

217

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

SciTech Connect

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

Zinder, S.

1991-01-01

218

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

SciTech Connect

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

Zinder, S.

1991-12-31

219

Reduction of aerobic acetate production by Escherichia coli.  

PubMed Central

Acetate excretion by Escherichia coli during aerobic growth on glucose is a major obstacle to enhanced recombinant protein production. We report here that the fraction of carbon flux through the anaplerotic pathways is one of the factors influencing acetate excretion. Flux analysis of E. coli central metabolic pathways predicts that increasing the fraction of carbon flux through the phosphoenolpyruvate carboxylase (PPC) pathway and the glyoxylate bypass reduces acetate production. We tested this prediction by overexpressing PPC and deregulating the glyoxylate bypass by using a fadR strain. Results show that the acetate yield by the fadR strain with PPC overexpression is decreased more than fourfold compared to the control, while the biomass yield is relatively unaffected. Apparently, the fraction of carbon flux through the anaplerotic pathways is one of the factors that influence acetate excretion. These results confirm the prediction of our flux analysis and further suggest that E. coli is not fully optimized for efficient utilization of glucose. PMID:9251207

Farmer, W R; Liao, J C

1997-01-01

220

Probing reaction pathways on model catalyst surfaces: Vinyl acetate synthesis and olefin metathesis  

Microsoft Academic Search

The reaction pathway for the palladium-catalyzed synthesis of vinyl acetate from acetic acid, ethylene and oxygen is investigated using reflection–absorption infrared spectroscopy by monitoring the rate of acetate titration by gas-phase ethylene. This reveals that acetate species are removed by reaction with gas-phase ethylene resulting in vinyl acetate formation. Reaction with C2D4 reveals a large (?6) isotope effect indicating that

Feng Gao; Yilin Wang; Florencia Calaza; Dario Stacchiola; Wilfred T. Tysoe

2008-01-01

221

[Conversion of acetic acid to methane by thermophiles  

SciTech Connect

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

Zinder, S.H.

1993-01-01

222

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

PubMed

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

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

2006-02-01

223

Syntrophic acetate oxidation in industrial CSTR biogas digesters.  

PubMed

The extent of syntrophic acetate oxidation (SAO) and the levels of known SAO bacteria and acetate- and hydrogen-consuming methanogens were determined in sludge from 13 commercial biogas production plants. Results from these measurements were statistically related to the prevailing operating conditions, through partial least squares (PLS) analysis. This revealed that high abundance of microorganisms involved in SAO was positively correlated with relatively low abundance of aceticlastic methanogens and high concentrations of free ammonia (>160 mg/L) and volatile fatty acids (VFA). Temperature was identified as another influencing factor for the population structure of the syntrophic acetate oxidising bacteria (SAOB). Overall, there was a high abundance of SAOB in the different digesters despite differences in their operating parameters, indicating that SAOB are an enduring and important component of biogas-producing consortia. PMID:24333792

Sun, Li; Müller, Bettina; Westerholm, Maria; Schnürer, Anna

2014-02-10

224

Isothermal decomposition of gamma-irradiated palladium acetate  

NASA Astrophysics Data System (ADS)

The isothermal decomposition of un-irradiated (pristine) and pre-gamma-irradiated palladium acetate was studied in the temperature range (498-508 K) and in air using the isothermal thermogravimetric technique. The data were analysed using various solid state reaction models. The results showed that the kinetics of isothermal decomposition of palladium acetate was governed by random nucleation reaction (Erofe'ev equation A(3)). The activation energies of the main decomposition process for un-irradiated and pre-gamma-irradiated samples were calculated. The change in texture and crystal structure of the investigated palladium acetate by gamma-irradiation was studied using electron microscopy and X-ray diffraction techniques.

Mahfouz, R. M.; Alshehri, S. M.; Monshi, M. A. S.; Abd El-Salam, N. M.

2004-06-01

225

Delineation of LASIK Flaps with Prednisolone Acetate Eyedrops  

PubMed Central

We describe the use and safety of prednisolone acetate eyedrops at the end of laser in situ keratomileusis (LASIK) to aid proper positioning of the corneal flap. The LASIK flap is created using the preferred technique. Following laser ablation and flap repositioning, one drop of prednisolone acetate is instilled on the eye. This delineates the flap “gutters” and allows perfect flap positioning and centration. We used this technique in 425 eyes undergoing LASIK for correction of spherocylindrical refractive errors. Flap margins were adequately delineated intraoperatively. The only complication related to the use of the steroid suspension was crystal deposition under the flap in one case which resolved completely in 48 hours. PMID:24982743

Fahd, Daoud C; Fahed, Sharbel D

2014-01-01

226

Abiraterone Acetate and Castration Resistant Ductal Adenocarcinoma of the Prostate  

PubMed Central

Ductal adenocarcinoma of the prostate is a rare histological variant that only represents <1% of prostate tumors. This histological variant has several important clinical implications with respect to their evolution, clinical prognosis, and treatment. We report the case of a 64-year-old patient with ductal adenocarcinoma of the prostate, which progresses to castration-resistant prostate cancer, that was treated with abiraterone acetate with good clinical response, to our knowledge, the first case of ductal adenocarcinoma of the prostate in treatment with abiraterone acetate. PMID:24891969

Linden-Castro, Edgar; Pelayo-Nieto, Marcela; Alias-Melgar, Alejandro; Espinosa-Perezgrovas, Daniel; Ramirez-Galindo, Ivan; Catalan-Quinto, Gabriel

2014-01-01

227

Fate and residues of trenbolone acetate in edible tissues from sheep amd calves implanted with tritium-labeled trenbolone acetate  

SciTech Connect

In order to study the fate and residues of trenbolone acetate in edible tissues, two groups of six animals from two ruminant species (ewes and calves) were implanted with (3H)trenbolone acetate. The distribution of extractable radioactive residues was measured in liver, kidney and muscle. We found that the largest proportion of residues was not extractable and thus was considered as covalently bound residues. The proportion of the main extractable metabolites (17 alpha-trenbolone, trendione, 17 beta-trenbolone) was measured. The evaluation of the distribution of trenbolone acetate metabolites directly soluble in water showed that unknown metabolite(s) were predominant. The covalent binding to nucleic acids was measured. It was so low that it was not detectable. The results are discussed in light of the data presented in the scientific report on anabolic agents in animal production from the European scientific working group.

Evrard, P.; Maghuin-Rogister, G.; Rico, A.G. (Univ. of Liege (Belgium))

1989-06-01

228

Concentration-detection functions for the odor of homologous n-acetate esters  

PubMed Central

Using air-dilution olfactometry, we measured concentration-response functions for the odor detection of the homologous esters ethyl, butyl, hexyl, and octyl acetate. Stimuli were delivered by means of an 8-station vapor delivery device (VDD-8) specifically designed to capture odor detection performance by humans under environmentally realistic conditions. Groups of 16–17 (half female) normosmic (i.e., having a normal olfaction) non-smokers (ages 18–38) were tested intensively. The method involved a three-alternative forced-choice procedure against carbon-filtered air, with an ascending concentration approach. Delivered concentrations were confirmed by gas chromatography before and during actual testing. A sigmoid (logistic) model provided an excellent fit to the odor detection functions both at the group and individual levels. Odor detection thresholds (ODTs) (defined as the half-way point between chance and perfect detection) decreased from ethyl (245 ppb by volume), to butyl (4.3 ppb), to hexyl acetate (2.9 ppb), and increased for octyl acetate (20 ppb). Interindividual threshold variability was near one and always below two orders of magnitude. The steepness of the functions decreased slightly but significantly with carbon chain length. The outcome showed that the present thresholds lie at the very low end of those previously reported, but share with them a similar relative trend across n-acetates. On this basis, we suggest that a recent quantitative structure-activity relationship (QSAR) for ODTs can be applied to these and additional optimized data, and used to describe and predict not just ODTs but the complete underlying psychometric odor functions. PMID:18950650

Cometto-Muniz, J. Enrique; Cain, William S.; Abraham, Michael H.; Gil-Lostes, Javier

2008-01-01

229

Cu(II) acetate- and Mn(III) acetate-mediated radical reactions of [60]fullerene with ketonic compounds.  

PubMed

The copper(II) acetate monohydrate- or manganese(III) acetate dihydrate-mediated reaction of [60]fullerene with beta-keto esters 1a-1c or with beta-diketones 1d,1e in the presence of 4-dimethylaminopyridine afforded only dihydrofuran-fused C60 derivatives 2a-2e. However, aromatic methyl ketones 3a-3c gave two kinds of products: methanofullerenes 4a-4c and dihydrofuran-fused C60 derivatives 5a,5b. Possible reaction mechanisms are proposed. PMID:15731864

Wang, Guan-Wu; Li, Fa-Bao

2005-03-01

230

Growth and Methanogenesis by Methanosarcina Strain 227 on Acetate and Methanol  

PubMed Central

Methanosarcina strain 227 exhibited exponential growth on sodium acetate in the absence of added H2. Under these conditions, rates of methanogenesis were limited by concentrations of acetate below 0.05 M. One mole of methane was formed per mole of acetate consumed. Additional evidence from radioactive labeling studies indicated that sufficient energy for growth was obtained by the decarboxylation of acetate. Diauxic growth and sequential methanogenesis from methanol followed by acetate occurred in the presence of mixtures of methanol and acetate. Detailed studies showed that methanol-grown cells did not metabolize acetate in the presence of methanol, although acetate-grown cells did metabolize methanol and acetate simultaneously before shifting to methanol. Acetate catabolism appeared to be regulated in response to the presence of better metabolizable substrates such as methanol or H2-CO2 by a mechanism resembling catabolite repression. Inhibition of methanogenesis from acetate by 2-bromoethanesulfonate, an analog of coenzyme M, was reversed by addition of coenzyme M. Labeling studies also showed that methanol may lie on the acetate pathway. These results suggested that methanogenesis from acetate, methanol, and H2-CO2 may have some steps in common, as originally proposed by Barker. Studies with various inhibitors, together with molar growth yield data, suggest a role for electron transport mechanisms in energy metabolism during methanogenesis from methanol, acetate, and H2-CO2. PMID:216307

Smith, Michael R.; Mah, Robert A.

1978-01-01

231

Continuum of Mechanisms for Nucleophilic Substitutions of Cyclic Acetals  

PubMed Central

The effect of nucleophile strength on diastereoselectivity in the nucleophilic substitution of cyclic acetals was explored. Stereoselectivity remained constant and high as nucleophilicity increased until a threshold value was reached. Beyond this point, however, selection of Lewis acid determined whether stereochemical inversion or erosion was observed. PMID:18844363

Krumper, Jennifer R.; Salamant, Walter A.; Woerpel, K. A.

2009-01-01

232

Synthesis of methyl acetate from syngas via dimethyl ether  

SciTech Connect

Dimethyl ether (DME) can be used as a building block for a variety of specialty chemicals in the petrochemical industry. Its utilization stems mainly from its efficient production from synthesis gas in a single stage. This Liquid Phase Dimethyl Ether (LP-DME) process, based on dual catalysts slurried in inert oil, can alleviate the chemical equilibrium limitation governing the methanol synthesis reaction and concurrently improve once-through syngas conversion and reactor productivity. Studies in the past have focused on using DME as a feedstock for gasoline range hydrocarbons as well as lower olefins. The focus of this investigation is to study the synthesis of methyl acetate, an important intermediate for acetic acid, from dimethyl ether. In particular, conversion of DME to methyl acetate is investigated over a variety of Group VIII metal substituted phosphotungstic acid salts. Key aspects of the process such as the effect of active metal, support types, multiple metal loading, and feed conditions are examined. Thus, this paper introduces a novel process route for synthesis of methyl acetate from natural gas-based syngas via dimethyl ether as an intermediate.

Tartamella, T.; Sardesai, A.; Lanterman, H.B.; Lee, S.

1999-07-01

233

Synthesis of vinyl acetate on palladium-based catalysts  

E-print Network

Vinyl acetate (VA) is an important monomer used in the production of paints, surface coatings and adhesives. Synthesis of VA is usually carried out over supported Pd alloy catalysts with a selectivity as high as 96% and described as C2H4 + CH3COOH...

Kumar, Dheeraj

2009-06-02

234

Urinary Phenyl Acetate: A Diagnostic Test for Depression?  

Microsoft Academic Search

The compound 2-phenylethylamine is an ``endogenous amphetamine'' which may modulate central adrenergic functions. 2-Phenylethylamine is mainly metabolized by monoamine oxidase to form phenyl acetate (PAA). The 24-hour urinary excretion of PAA was measured in normal healthy volunteers and depressed patients. Patients were diagnosed according to the Diagnostic and Statistical Manual of Mental Disorders, edition 3. In 70 percent of healthy

H. C. Sabelli; J. Fawcett; F. Gusovsky; J. Javaid; J. Edwards; H. Jeffriess

1983-01-01

235

Hydrogen bonding of hydrates of double acetic acid molecules.  

PubMed

In the chemical industry, the separation of the acetic acid from the HAc/H(2)O system is always influenced by the hydrogen bonding. In the present work, an investigation on the hydrogen bonding of various hydrates of double acetic acid (HAc) molecules is carried out with two first-principle methods including ab initio molecular dynamics (AIMD) simulation and quantum chemical calculations (QCC). From the AIMD simulation, the distribution of the head-on rings of acetic acid is revealed and shows that the favorable structures tend to be the acetic acid hydrates rather than the HAc cyclic dimer. The 6- and 10-membered head-on rings involving single and double HAc molecules, respectively, appear to be the dominant structures. According to the QCC, the most stable structure is found to be the conformer with the biggest head-on ring in each group. The energetics of the rings indicates that the stability of the ring increases with increased ring size (with the exception of the 9-membered ring), and the 10-membered ring is the most stable. The relative stability of the ring structures implied by the static QCC result is in good agreement with the statistical ring distribution of the AIMD simulation. PMID:19462952

Pu, Liang; Sun, Yueming; Zhang, Zhibing

2009-06-18

236

THERMOREGULATION IN MICE FOLLOWING ACUTE ADMINISTRATION OF LEAD ACETATE  

EPA Science Inventory

Several reports in the literature suggest a relationship between lead intoxication and thermoregulatory capacity. To investigate the effects of lead on the control of body temperature, mice of the BALB/c strain were injected intraperitoneally with lead acetate (0 to 100 mg/kg) wh...

237

Synthesis of Modified Poly(vinyl acetate) Adhesives  

Microsoft Academic Search

Modified poly(vinyl acetate) copolymers with drying oils as comonomers have been prepared. The unsaturated triglycerides can produce cross-linking and give a waterproof effect due to their hydrophobicity. The new copolymers synthesized by solution polymerization in an organic medium have been submitted to analytical characterization in order to investigate the role of the drying oils in the polymerization reaction. NMR spectroscopy

A. Salvini; L. M. Saija; M. Lugli; G. Cipriani; C. Giannelli

2010-01-01

238

Asymmetric Hydrogenation of Itaconic Acid and Enol Acetate Derivatives with  

E-print Network

. A variety of chiral 2-substituted succinic acids and chiral acetates have been obtained in excellent ee efficient synthesis of chiral R-amino acids via transition metal-catalyzed asymmetric hydrogenation has become one of most efficient methods for the synthesis of chiral R-amino acids, chiral -amino

Zhang, Xumu

239

Superacidic low-temperature cyclization of terpenols and their acetates  

Microsoft Academic Search

The superacidic low-temperature cyclization of terpenols and their acetates by fluorosulfonic acid represents a highly efficient chemo- and structurally selective and stereospecific process. Homoallylic alcohols (a-isomers of cycloterpenols) are the products of cyclization of terpenols; the configuration of the hydroxymethyl group in the products is predetermined by the configuration of the allylic double bond in aliphatic or partially cyclized precursors.

P. F. Vlad; N. D. Ungur; Nguen Hung; V. B. Perutsky

1995-01-01

240

Electronic interactions between gold films and mn12-acetate  

E-print Network

the presence of a surface layer of Mn12–acetate, have been performed using a dilution refrigerator. Quantitative fits to the data using the predictions of weak localization theory were performed using a least-squares fit method in order to determine...

Means, Joel Lewis

2009-05-15

241

Synthesis and characterization of cyclic acetal based degradable hydrogels  

Microsoft Academic Search

While many synthetic, hydrolytically degradable hydrogels have been developed for biomedical applications, there are only a few examples whose polymer backbone does not form acidic products upon degradation. In order to address this concern, we proposed to develop a hydrogel based on a cyclic acetal unit that produces diols and propanals upon hydrolytic degradation. In particular, we proposed the fabrication

Sachiko Kaihara; Shuichi Matsumura; John P. Fisher

2008-01-01

242

pKa of acetate in water: a computational study.  

PubMed

Several computational methods including the conductor-like polarizable continuum model, CPCM with both UAKS and UAHF cavities, Cramer and Truhlar's generalized Born solvation model, SM5.4(AM1), SM5.4(PM3), and SM5.43R(mPW1PW91/6-31+G(d)), and mixed QM/MM-Ewald simulations were used to calculate the pK(a) values of acetate and bicarbonate anions in aqueous solution. This work provided a critical and comprehensive assessment of the quality of these theoretical models in the calculation of aqueous solvation free energies for the singly charged acetate and bicarbonate ions, as well as the doubly charged acetate dianion and carbonate dianion. It was shown that QM/MM-Ewald simulations could give an accurate and consistent evaluation of the pK(a) values of acetate and bicarbonate based on both the relative and absolute pK(a) formulas, while other methods could yield satisfactory results only for certain calculations. However, this does not mean that the current QM/MM-Ewald protocol is superior to other methods. The useful information obtained in this investigation is that both the absolute and relative pK(a) formulas should better be tested in accurate calculations of pK(a) values based on any methods. PMID:16863127

Gao, Daqing; Svoronos, Paris; Wong, Peter K; Maddalena, Deborah; Hwang, Junwoong; Walker, Hughton

2005-12-01

243

Miscibility Between Ethylene Vinyl Acetate Copolymers and Tackifier Resins  

Microsoft Academic Search

A series of ethylene vinyl acetate copolymer (EVA) were blended with various kinds of tackifiers and the miscibility between the components was investigated. The miscibility of the blend is illustrated as a phase diagram. The EVA and modified rosin systems tended to have a phase diagram with lower critical solution temperature (LCST), whereas the EVA and petroleum resin systems tended

Mototsugu Takemoto; Takuma Karasawa; Hiroshi Mizumachi; Mikio Kajiyama

2000-01-01

244

Original article Effect of 1-naphthalene acetic acid concentrations and  

E-print Network

) Abstract - Field experiments were performed in two successive seasons at the Experimental Station, Faculty.). Cotton plants were sprayed with the growth regulator 1-naphthalene acetic acid (NAA) once (90 days after planting (DAP)), or twice (90 and 105 DAP) or three times (90, 105 and 120 DAP), during the square

Paris-Sud XI, Université de

245

Effects of acetic acid on light scattering from cells  

PubMed Central

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

Marina, Oana C.; Sanders, Claire K.; Mourant, Judith R.

2012-01-01

246

40 CFR 180.595 - Flufenpyr-ethyl; tolerances for residues.  

Code of Federal Regulations, 2011 CFR

...General. (1) Tolerances are established for residues of the herbicide, flufenpyr-ethyl; acetic acid, [2-chloro-4-fluoro-5...01 (2) Tolerances are established for residues of the herbicide flufenpyr-ethyl; acetic acid,...

2011-07-01

247

40 CFR 180.595 - Flufenpyr-ethyl; tolerances for residues.  

Code of Federal Regulations, 2012 CFR

...General. (1) Tolerances are established for residues of the herbicide, flufenpyr-ethyl; acetic acid, [2-chloro-4-fluoro-5...01 (2) Tolerances are established for residues of the herbicide flufenpyr-ethyl; acetic acid,...

2012-07-01

248

40 CFR 180.595 - Flufenpyr-ethyl; tolerances for residues.  

Code of Federal Regulations, 2010 CFR

...General. (1) Tolerances are established for residues of the herbicide, flufenpyr-ethyl; acetic acid, [2-chloro-4-fluoro-5...01 (2) Tolerances are established for residues of the herbicide flufenpyr-ethyl; acetic acid,...

2010-07-01

249

40 CFR 180.595 - Flufenpyr-ethyl; tolerances for residues.  

Code of Federal Regulations, 2013 CFR

...General. (1) Tolerances are established for residues of the herbicide, flufenpyr-ethyl; acetic acid, [2-chloro-4-fluoro-5...01 (2) Tolerances are established for residues of the herbicide flufenpyr-ethyl; acetic acid,...

2013-07-01

250

An in vitro investigation of water sorption and solubility of two acetal denture base materials.  

PubMed

Acetal resins have been used as an alternative denture base and clasp material recently. The aim of this study was to compare water sorption and water solubility of pink and white acetal resins as compared to a heat-polymerized polymethyl methacrylate resin (PMMA). The tests were performed in accordance with International Standards Organization specification No: 1567. Pink acetal resin showed significantly lower water sorption than heat-polymerized acrylic resin and white acetal resin. PMMA showed significantly higher solubility than pink and white acetal resin. Water sorption and solubility of PMMA, pink and white acetal resins were within the ISO specification limit. PMID:16180637

Arikan, Ayla; Ozkan, Yasemin Kulak; Arda, Tugberk; Akalin, Buket

2005-09-01

251

High pressure vapour–liquid equilibria of the binary and some of the ternary and multicomponent mixtures of the carbon dioxide + acetic anhydride + ?-methylbenzyl alcohol + acetic acid + ?-methylbenzyl acetate system  

Microsoft Academic Search

Bubble-point pressures of the binary systems CO2+acetic anhydride, CO2+?-methylbenzyl alcohol, and CO2+?-methylbenzyl acetate were measured in the temperature range of 283–363K up to 15MPa in a high pressure capillary glass tube apparatus, using the synthetic method. The binary mixture CO2+acetic acid was measured for x=0.4962 and compared with previously published results. For the system CO2+?-methylbenzyl alcohol, data of the three-phase

Lourdes Calvo; Theo W. de Loos

2006-01-01

252

Microwave Spectra of Molecules of Astrophysical Interest. XXVI. Acetic Acid ,,CH3COOH...  

E-print Network

Microwave Spectra of Molecules of Astrophysical Interest. XXVI. Acetic Acid ,,CH3COOH... V The microwave spectrum of acetic acid is critically reviewed and supplemented with spectral frequency; microwave spectrum; radio astronomy; rota- tional transitions. CONTENTS 1. Introduction

Magee, Joseph W.

253

The formation of acetic acid from carbon dioxide and hydrogen by anaerobic spore-forming bacteria  

Microsoft Academic Search

Summary Further experiments on an anaerobic bacillus synthesising acetic acid from CO2 and H2 are described. The organism in question was classified asClostridium aceticum n.sp. Acetic acid is also formed from sugar.

K. T. Wieringa

1939-01-01

254

PolarIndole-3-acetic AcidDiffusion inNonliving and  

Microsoft Academic Search

Polarindole-3-acetic acidmovementwasobserved inkilled plantsegments andinartificial modelsystems. Thepolar dif- fusion ofindole-3-acetic acidwasobserved intissue killed by chemical orphysical meansinan agar-plant systemandina multicelled Plexiglas dialysis chambercontaining hypocotyl tissue gradients orgradients ofanionexchange material. Itwassuggested thatpolar indole-3-acetic acidmovement in excised segments maybeareflection ofthediffusion ofindole- 3-acetic acidthrough asymmetric gradients ofmaterials with binding characteristics somewhatsimilar toionexchange. Thatpolar movementofIAA isan active process, pre- sumably dependent upon\\

W. R. KRUL

255

Investigations of sodium acetate trihydrate for solar latent heat storage, controlling the melting point  

NASA Astrophysics Data System (ADS)

The addition of different acetate salts and acetamide lowers the melting point of sodium acetate trihydrate. Between 0 and 10 percent of lithium acetate dihydrate a linear relationship was observed between the melting point and the molal concentration, and the cryoscopic constant of Kf = -6.8 C (+ or - 10 percent) was evaluated. Information on dissociation or dimerization of the various additives could be deduced from the results. The positive properties of sodium acetate trihydrate were retained.

Ulman, A.; Valentin, B.

1983-09-01

256

Oral acetate supplementation after prolonged moderate intensity exercise enhances early muscle glycogen resynthesis in horses.  

PubMed

Oral acetate supplementation enhances glycogen synthesis in some mammals. However, while acetate is a significant energy source for skeletal muscle at rest in horses, its effects on glycogen resynthesis are unknown. We hypothesized that administration of an oral sodium acetate-acetic acid solution with a typical grain and hay meal after glycogen-depleting exercise would result in a rapid appearance of acetate in blood with rapid uptake by skeletal muscle. It was further hypothesized that acetate taken up by muscle would be converted to acetyl CoA (and acetylcarnitine), which would be metabolized to CO2 and water via the tricarboxylic acid cycle, generating ATP within the mitochondria and thereby allowing glucose taken up by muscle to be preferentially incorporated into glycogen. Gluteus medius biopsies and jugular venous blood were sampled from nine exercise-conditioned horses on two separate occasions, at rest and for 24 h following a competition exercise test (CET) designed to simulate the speed and endurance test of a 3 day event. After the CETs, horses were allowed water ad libitum and either 8 l of a hypertonic sodium acetate-acetic acid solution via nasogastric gavage followed by a typical hay-grain meal (acetate treatment) or a hay-grain meal alone (control treatment). The CET significantly decreased muscle glycogen concentration by 21 and 17% in the acetate and control treatments, respectively. Acetate supplementation resulted in a rapid and sustained increase in plasma [acetate]. Skeletal muscle [acetyl CoA] and [acetylcarnitine] were increased at 4 h of recovery in the acetate treatment, suggesting substantial tissue extraction of the supplemented acetate. Acetate supplementation also resulted in an enhanced rate of muscle glycogen resynthesis during the initial 4 h of the recovery period compared with the control treatment; however, by 24 h of recovery there was no difference in glycogen replenishment between trials. It is concluded that oral acetate could be an alternative energy source in the horse. PMID:19429643

Waller, Amanda P; Geor, Raymond J; Spriet, Lawrence L; Heigenhauser, George J F; Lindinger, Michael I

2009-08-01

257

Isothermal decomposition of gamma-irradiated dysprosium acetate  

NASA Astrophysics Data System (ADS)

Isothermal decomposition of un-irradiated and pre-gamma-irradiated dysprosium acetate [Dy(CH3COO)(3)] has been investigated at different temperatures between 603-623 K. Irradiation was observed to enhance the rate of decomposition without modifying the mechanism of the thermal decomposition. Thermal decomposition of dysposium acetate is shown to proceed by a nucleation and growth mechanism (Avarmi-Erofe'ev equation) both for un-irradiated and pre-gamma-irradiated samples. The enhancement of the decomposition was found to increase with an increase in the gamma-ray dose applied to the sample and may be attributed to an increase in point defects and formation of additional nucleation centers generated in the host lattice. Thermodynamic values of the main decomposition process were calculated and evaluated.

Mahfouz, R. M.; Al-Shehri, S. M.; Monshi, M. A. S.; Abd El-Salam, N. M.

258

Molecular glass photoresists based on acidolysis of acetal compounds  

NASA Astrophysics Data System (ADS)

Molecular glass resists are low molecular-weight organic photoresist materials that readily form stable amorphous glasses above room temperature. They can lead to high resolution patterns. New families of ester acetal molecular glass materials have been created by the reaction between monocarboxylic acid and divinyl ethers. These organic materials are monodisperse and amorphous. They can be dissolved in common solvents and possess high thermal stability. The ester acetal compounds can be quickly decomposed at the presence of strong acid generated by photoacid generator (PAG) at room temperature or higher temperature and become easily soluble in dilute aqueous base. They can form positive photoresists together with PAG. The lithographic performance of the resist materials is being evaluated.

Wang, Liyuan; Zhai, Xiaoxiao; Xu, Na

2008-03-01

259

Mode of Action of the Antibacterial Compound Dequalinium Acetate  

PubMed Central

Dequalinium acetate is taken up rapidly by bacterial cells. Unlike the membrane-active drugs exemplified by cetrimide or chlorhexidine, its capacity for damaging the plasma membrane is low. The drug appears to penetrate quite rapidly into the cytoplasm where its effect seems to be exerted. A review of the evidence obtained in this study suggests that nucleic acid-containing components of the cell may be the prime target of this compound. PMID:4975451

Hugo, W. B.; Frier, M.

1969-01-01

260

Acetic Acid Synthesis by Catalytic Carbonylation of Methanol  

Microsoft Academic Search

Acetic acid synthesis via the carbonylation of methanol is one of the most important industrial applications\\u000a of catalysis using organometallic compounds. All the group 9 metals are active, with processes based on\\u000a cobalt, rhodium and iridium having been developed since the 1960s. This paper surveys some of the more\\u000a recent approaches employed for improving the performance of the rhodium- and

Anthony Haynes

261

Crosslinkable poly(vinyl acetate) emulsions for wood adhesive  

Microsoft Academic Search

Purpose – The purpose of this paper is to enhance the water resistance and the heat resistance of poly(vinyl acetate) (PVAc) emulsion adhesive, by providing the emulsion with controllable thermosetting capability. Design\\/methodology\\/approach – Emulsion polymerisation was used to synthesise PVAc\\/VeoVa 10 copolymers with varying proportions of acetoacetoxyethyl methacrylate (AAEM) incorporated in the copolymer chains. The AAEM component provided sites for

Jia Lu; Allan J. Easteal; Neil R. Edmonds

2011-01-01

262

Acetic Acid Bacteria Taxonomy from Early Descriptions to Molecular Techniques  

Microsoft Academic Search

The exploitation of acetic acid bacteria (AAB) has a long history in fermentation processes and now represents an emerging\\u000a field in biotechnological applications, especially with regard to the biosynthesis of useful chemicals with a potentially\\u000a high economic value and, in food science, through the standardization of microbiological processes for the manufacture of\\u000a both vinegar and other fermented beverages.

Maria Gullo; Paolo Giudici

263

DELAYED IMPLANTATION IN INTACT RATS TREATED WITH MEDROXYPROGESTERONE ACETATE  

Microsoft Academic Search

Summary. Intact, female Holtzman rats were treated daily with medroxyprogesterone acetate (map; Provera) in corn oil, beginning on the day of insemination. This caused delay of implantation in 14% (0\\\\m=.\\\\5mg\\/day) to 100% (2\\\\m=.\\\\4mg\\/day) of the animals tested. It is possible that map suppresses the synthesis or the release of luteinizing hormone (lh) from the pituitary gland and thus prevents the

LESTER E. BARNES; ROLAND K. MEYER

1964-01-01

264

Gonadotrophin-induced ovulation in melengestrol acetate treated female goat.  

PubMed

Adult, Black Bengal goats synchronized to oestrus with Melengestrol Acetate (MGA) could be subjected to superovulation with 1000 IU of the Pregnant Mare Serum Gonadotrophin (PMSG). However, with 500 IU of PMSG higher rate of ovulation observed only in goats above one year age was not significant. Results indicate that the successful superovulation in MGA synchronized goats depend both on the dosage of the PMSG, as well as upon the age of the treated animal. PMID:6682831

Sanwal, P C; Pande, J K; Varshney, V P; Mogha, I V

1983-01-01

265

The environmental fate of anabolic steroid trenbolone acetate  

Microsoft Academic Search

17?-trenbolone Acetate (TBA) is a synthetic anabolic hormone widely used in beef cattle across the U.S. TBA is administered as a subcutaneous implant and often in combination with 17?-estradiol (E2) for growth promotion in beef cattle. Implanted cattle excrete primarily 17?-trenbolone along with small amounts of 17?-trenbolone and trendione. Quantifying the fate of these hormones after being land-applied is important

Bushra Khan

2009-01-01

266

Use of fibre wastes from production of acetate fibres  

SciTech Connect

The rational use of production wastes is an important part of the Fergana Chemical Fibre Plant in Russia. This recycling reduces the negative effect of the technological process on the environment, increases the economy of production, and produces additional consumer goods. Consumer goods began to be produced at the plant in 1978 with processing of amide-acetate textured fibres into yarn for hand knitting. The need to increase the volumes and expand the variety of goods for the market predetermined an important increase in production of this product. Production of consumer goods has increased since 1990, and both fibre wastes and untreated low-grade fibres and filaments have been used as the starting material. Technological processes for processing wastes and low-grade figured, textured polyamide-acetate fibres into knitting yarn, haberdashery cord, and finishing tape and fringe were created and introduced in subsequent years. The primary technological formulation for production of these materials is well known and is used in light industry. However, production of each type of product in the plant was preceded by research related to selection of the optimum linear density of the filaments used, composition of blends, and the structure of figured fibres, as well as the concrete technological parameters and operating regimes of the equipment to produce articles of the required quality. Development and testing of new decorative textiles are continuing. Low grade and nonstandard acetate semifinished fibre from spinning machines and low grade, bulk dyed acetate fibres have been selected as the raw material for fabrication of these articles.

Askarov, M.I.; Tashpulatova, A.B.

1995-07-01

267

Ferroelectric thin film bismuth titanate prepared from acetate precursors  

SciTech Connect

Bismuth titanate (Bi{sub 4}Ti{sub 3}O{sub 12}) thin films were fabricated by spin coat deposition followed by rapid thermal processing (RTP). Acetate derived solutions for deposition were synthesized by blending bismuth acetate in aqueous acetic acid and then adding titanium acetate. A series of electrically insulating, semiconducting and conducting substrates were evaluated for Bi{sub 4}Ti{sub 3}O{sub 12} film deposition. While X-ray diffraction and TEM analyses indicated that the initial perovskite crystallization temperature was 500{degrees}C or less for these Bi{sub 4}Ti{sub 3}O{sub 12} films, a 700{degrees}C crystallization treatment was used to obtain single phase perovskite films. Bi{sub 4}Ti{sub 3}O{sub 12} film crystallographic orientation was shown to depend on three factors: substrate surface morphology, the number of coating layers and thermal processing. While preferred c-direction orientation was observed for Bi{sub 4}Ti{sub 3}O{sub 12} films deposited on silver foil substrates, preferred a-direction orientation was obtained for films deposited on both Si and Pt coated Si wafers. The films were dense, smooth, crack free, and had grain sizes ranging from 20 nm to 100 nm. Film thickness and refractive index were determined using a combination of ellipsometry, waveguide refractometry and TEM measurements. Both low field dielectric and ferroelectric properties were measured for an 800 nm thick film deposited on a Pt coated MgO substrate. A remanent polarization of 38 {mu}C/cm{sup 2} and a coercive field of 98 kV/cm were measured for this film that was crystallized at 700{degrees}C.

Lu, Yanxia; Hoelzer, D.T.; Schulze, W.A. [Alfred Univ., NY (United States); Tuttle, B.A.; Potter, B.G. [Sandia National Labs., Albuquerque, NM (United States)

1994-10-01

268

[Cyproterone acetate - ethinylestradiol treatment of hirsutism, acne, seborrhea and alopecia].  

PubMed

Twenty-five female patients, aged 14 to 49, and suffering from syptoms of virilization (hirsutism, acne, seborrhea and alopecia) were treated with an estrogen-progestogen combinantion, i.e. cyproterone acetate and ethinylestradiol, having antiandrogenic and antiovulatory action. Patients were submitted to monitoring by means of a series of laboratory tests in order to detect any toxic or hormonal effects that might occur. In most cases symptoms of virilization were significantly reduced, while untoward side effects were not noted. PMID:127497

Nardi, M; De Aloysio, D; Busacchi, P; Flamigni, C

1975-06-01

269

The production of isoamyl acetate using immobilized lipases in a solvent-free system  

Microsoft Academic Search

Isoamyl acetate production was investigated using immobilized Rhizomucor miehei and Candida antarctica lipases by esterification of acetic acid with isoamyl alcohol in a solvent-free system. The acid–alcohol molar ratio, enzyme type and amount, reaction time, temperature and shaking rate were chosen as efficient reaction parameters. The initial reaction rate, isoamyl acetate concentration and conversion values obtained using Novozym 435 were

Afife Güvenç; Nurcan Kapucu; Ülkü Mehmeto?lu

2002-01-01

270

40 CFR 721.8658 - Modified polymer of vinyl acetate and quaternary ammonium compound (generic).  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Modified polymer of vinyl acetate and quaternary ammonium...Chemical Substances § 721.8658 Modified polymer of vinyl acetate and quaternary ammonium...substance identified generically as modified polymer of vinyl acetate and quaternary...

2011-07-01

271

40 CFR 721.8658 - Modified polymer of vinyl acetate and quaternary ammonium compound (generic).  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Modified polymer of vinyl acetate and quaternary ammonium...Chemical Substances § 721.8658 Modified polymer of vinyl acetate and quaternary ammonium...substance identified generically as modified polymer of vinyl acetate and quaternary...

2010-07-01

272

Modeling of Escherichia coli growth and acetate formation under different operational conditions  

Microsoft Academic Search

A kinetic model for Escherichia coli growth and acetate formation is presented. Stoichiometric and energy balances reduce the number of kinetic equations to estimate. The formulation results in linear relations which establish the dependence of glucose consumption rate and acetate consumption rate with the independent rates, biomass and acetate formation rate. The proposed model has been used to simulate batch

Mar??a Jesus Guardia; Eloy Garc??a Calvo

2001-01-01

273

The enumeration and identification of acetic acid bacteria from South African red wine fermentations  

Microsoft Academic Search

Acetic acid bacteria are microorganisms that can profoundly influence the quality of wine. Surprisingly, little research has been done on these microorganisms in the winemaking field. The object of this study was to investigate the occurrence of acetic acid bacteria in South African red wine fermentations and to identify the dominant species occurring. Acetic acid bacteria were isolated and enumerated

W. J. Du Toit; M. G. Lambrechts

2002-01-01

274

21 CFR 175.350 - Vinyl acetate/crotonic acid copolymer.  

...2014-04-01 false Vinyl acetate/crotonic acid copolymer. 175.350 Section 175.350... § 175.350 Vinyl acetate/crotonic acid copolymer. A copolymer of vinyl acetate and crotonic acid may be safely used as a coating or...

2014-04-01

275

EVALUATION OF NATURAL SOURCE VITAMIN E, RRR--TOCOPHERYL ACETATE, AS AN ALTERNATIVE MICRONUTRIENT SOURCE AND  

E-print Network

EVALUATION OF NATURAL SOURCE VITAMIN E, RRR--TOCOPHERYL ACETATE, AS AN ALTERNATIVE MICRONUTRIENT APPROVAL EVALUATION OF NATURAL SOURCE VITAMIN E, RRR--TOCOPHERYL ACETATE, AS AN ALTERNATIVE MICRONUTRIENT: Evaluation of Natural Source Vitamin E, RRR--Tocopheryl Acetate, as an Alternative Micronutrient Source

276

The critical temperatures and densities of acetic acid?water mixtures  

Microsoft Academic Search

The critical temperatures and densities of acetic acid?water mixtures have been measured using a sealed ampule method. The measurements for pure acetic acid were compared with data reported in the literature and were found to be in good agreement. It is shown that the critical temperatures of acetic acid?water mixtures increase with the addition of water, and that the critical

V. Vandana; Amyn S. Teja

1995-01-01

277

Identification of dihydrogalangal acetate in galangal [Alpinia galangal (L.) Swartz] extracts.  

PubMed

Dihydrogalangal acetate has been discovered for the first time in galangal roots [Alpinia galangal (L.) Swartz]. The compound has a taste sensation similar to galangal acetatethe pungent principle of galangalbut it is more stable in food and beverage applications. Therefore, dihydrogalangal acetate provides many advantages as a flavor ingredient for alcohol enhancement and taste modification. Dihydrogalangal acetate is present in approximately 0.0005% of fresh roots and in about 0.004% of dried roots. (S)-Dihydrogalangal acetate is found as the main optical isomer in galangal roots (98%), while its minor (R)-isomer is less abundant (2%). Enantiomers of galangal acetate and dihydrogalangal acetate were separated and evaluated by sensory analysis. (R)-Galangal acetate has a very faint woody and sweet aroma, and (R)-dihydrogalangal acetate is almost odorless, while (S)-galangal acetate has strong and (S)-dihydrogalangal acetate has weak pungent and woody notes. Although the aroma characters of these optical isomers are different, taste sensations were found to have no significant differences among galangal acetate, dihydrogalangal acetate, and their optical isomers. PMID:19265449

Yang, Xiaogen; Rohr, Martin; Jordan, Jason

2009-04-22

278

Inhibition of C4 photosynthesis by (benzamidooxy)acetic acid.  

PubMed

(Benzamidooxy)acetic acid (common name benzadox) which has herbicidal properties was evaluated as a potential inhibitor of photosynthesis in C4 plants. Among enzymes of the C4 pathway, it was a relatively strong inhibitor of alanine aminotransferase in in vitro experiments at concentrations of 5mM. In benzadox treated leaves of Panicum miliaceum, a NAD-malic enzyme type C4 species, there was strong inhibition of both alanine and aspartate aminotransferase and of photosynthetic O2 evolution within one hour. Consistent with the inhibition of these enzymes of the C4 cycle, the pool sizes of metabolites of the cycle was altered: the aspartate level was increased two fold, while the levels of other metabolites such as pyruvate, alanine, oxalacetate and malate were decreased. Kinetic studies with partially purified alanine aminotransferase showed that benzadox is a competitive inhibitor with respect to alanine and a noncompetitive inhibitor with respect to 2-oxoglutarate. Comparisons between the structures and inhibitory actions of benzadox and (aminooxy)acetic acid, the latter a potent inhibitor of alanine and aspartate aminotransferases, suggest that in vivo, benzadox may exert its effect through metabolism to (aminooxy)acetic acid. PMID:24458342

Nakamoto, H; Ku, M S; Edwards, G E

1982-12-01

279

Ethylene-Vinyl Acetate Potential Problems for Photovoltaic Packaging: Preprint  

SciTech Connect

Photovoltaic (PV) devices are typically encapsulated using ethylene-vinyl acetate (EVA) to provide mechanical support, optical coupling, electrical isolation, and protection against environmental exposure. Under exposure to atmospheric water and/or ultraviolet radiation, EVA will decompose to produce acetic acid, lowering the pH and increasing the surface corrosion rates of embedded devices. Even though acetic acid is produced at a very slow rate, it may not take much to catalyze reactions that lead to rapid module deterioration. Another consideration is that the glass transition of EVA, as measured using dynamic mechanical analysis, begins at temperatures of about ?15 C. Temperatures lower than this can be reached for extended periods of time in some climates. Because of increased moduli below the glass transition temperature, a module may be more vulnerable to damage if a mechanical load is applied by snow or wind at low temperatures. Modules using EVA should not be rated for use at such low temperatures without additional low-temperature mechanical testing beyond the scope of UL 1703.

Kempe, M. D.; Jorgensen, G. J.; Terwilliger, K. M.; McMahon, T. J.; Kennedy, C. E.; Borek, T. T.

2006-05-01

280

Treatment of clozapine-induced priapism by goserline acetate injection.  

PubMed

Clozapine (Denzapine) is a treatment for resistant schizophrenia. Among the serious but rare side effects of clozapine are agranulocytosis and priapism. We hereby present the case of a 30-year-old man with a diagnosis of schizophrenia who has spent nearly 12 years of his adult life on various psychiatric in-patient units including open wards, secure units, psychiatric intensive care units and rehab wards. Diagnosed at the age of 15, he only responded to clozapine at the age of 18. Whilst being on clozapine he developed priapism in June 2010 and needed emergency surgical treatment in the form of surgical decompression. He again responded only to clozapine and fortunately he did not redevelop priapism; however, he was readmitted in February 2011 due to relapse, and he remained resistant to other antipsychotics. He was rechallenged with clozapine and recovered, but unfortunately redeveloped priapism which required emergency surgical and medical intervention (goserline acetate and tinzaperin injection). In order to relieve the recurrent priapism, he agreed to continue clozapine and goserline acetate injection. This decision was made by the patient in a compos mentis state. As far as we are aware, this is the first time goserline acetate has been reported as a successful treatment for clozapine-induced priapism. PMID:24167706

Kashyap, Gursharan Lal; Nayar, Jitendra; Bashier, Adnan; Varghese, Soosamma

2013-10-01

281

Comparative study of uptake and cellular distribution of Hg²°³-labeled phenyl-mercuric acetate and mercuric acetate by pea roots  

Microsoft Academic Search

Uptake and cellular distribution of mercury²°³ from dilute mercuric acetate of phenylmercuric acetate solutions by excised pea roots (Pisum sativum) have been investigated. The time course of uptake showed that the amount of mercury uptake was increased with the time of incubation, and was similar for inorganic mercury or phenylmercuric acetate. The trend of mercury²°³ incorporation into cellular components from

A. V. Rao; E. Fallin; S. C. Fang

1966-01-01

282

Demonstration, using Desulfobacter sp., of two pools of acetate with different biological availabilities in marine pore water  

Microsoft Academic Search

Desulfobacter sp. (Strain 3ac10), an acetate-utilizing sulphatereducing bacteria, was added to sterile marine pore water spiked with 14C-acetate, and changes in both the natural acetate pool and the added 14C-acetate were measured over time. Initially, both the added 14C-acetate and the chemically measured acetate were rapidly mineralized, but then the rate of removal decreased and a significant amount (approximately 20%)

R. J. Parkes; J. Taylor; D. Jørck-Ramberg

1984-01-01

283

Acetate/acetyl-CoA metabolism associated with cancer fatty acid synthesis: Overview and application.  

PubMed

Understanding cancer-specific metabolism is important for identifying novel targets for cancer diagnosis and therapy. Induced acetate/acetyl CoA metabolism is a notable feature that is related to fatty acid synthesis supporting tumor growth. In this review, we focused on the recent findings related to cancer acetate/acetyl CoA metabolism. We also introduce [1-(11)C]acetate positron emission tomography (PET), which is a useful tool to visualize up-regulation of acetate/acetyl CoA metabolism in cancer, and discuss the utility of [1-(11)C]acetate PET in cancer diagnosis and its application to personalized medicine. PMID:24569091

Yoshii, Yukie; Furukawa, Takako; Saga, Tsuneo; Fujibayashi, Yasuhisa

2015-01-28

284

Electrophilic cyclization of ?- and ?-geranyl acetates by mercury(II) trifluoroacetate  

Microsoft Academic Search

Electrophilic cyclization of ?-geranyl acetate promoted by mercury(II) trifluoroacetate leads to mixtures of ?- and ?-5?H-cyclogeranyl acetate derivatives and 6?-hydroxy-5?H-and 6?-hydroxy-5?H-cyclogeranyl acetate derivatives mercurated at the C-3 atom. The ratio of the unsaturated and hydroxymercurated products\\u000a depends on the reaction conditions. ?-Geranyl acetate reacts with mercury(II) trifluoroacetate to give a mixture of 6?-hydroxy-5?H-and 6?-hydroxy-5?H-geranyl acetates, mercurated at C-9, with an

V. N. Kulchitski; N. D. Ungur; P. F. Vlad

1997-01-01

285

Elevated acetate concentrations in the rhizosphere of Spartina alterniflora and potential influences on sulfate reduction  

NASA Technical Reports Server (NTRS)

Acetate is important in anaerobic metabolism of non-vegetated sediments but its role in salt marsh soils was not investigated thoroughly. Acetate concentrations, oxidation (C-14) and SO4(2-) reduction (S-35) were measured in S. alterniflora soils in NH and MA. Pore water from cores contained greater than 0.1 mM acetate and in some instances greater than 1.0 mM. Non-destructive samples contained less than 0.01 mM. Acetate was associated with roots and concentrations were highest during vegetative growth and varied with changes in plant physiology. Acetate turnover was very low whether whole core or slurry incubations were used. Radiotracers injected directly into soils yielded rates of SO4(2-) reduction and acetate oxidation not significantly different from core incubation techniques. Regardless of incubation method, acetate oxidation did not account for a significant percentage of SO4(2-) reduction. These results differ markedly from data for non-vegetated coastal sediments where acetate levels are low, oxidation rate constants are high and acetate oxidation rates greatly exceed rates of SO4(2-) reduction. The discrepancy between rates of acetate oxidation and SO4(2-) reduction in marsh soils may be due either to the utilization of substrates other than acetate by SO4(2-) reducers or artifacts associated with measurements of organic utilization by rhizosphere bacteria.

Hines, Mark E.; Tugel, Joyce B.; Giblin, A. E.; Banta, G. T.; Hobbie, J. E.

1992-01-01

286

Acetobacter aceti Possesses a Proton Motive Force-Dependent Efflux System for Acetic Acid  

PubMed Central

Acetic acid bacteria are obligate aerobes able to oxidize ethanol, sugar alcohols, and sugars into their corresponding acids. Among them, Acetobacter and Gluconacetobacter species have very high ethanol oxidation capacity, leading to accumulation of vast amounts of acetic acid outside the cell. Since these bacteria are able to grow in media with high concentrations of acetic acid, they must possess a specific mechanism such as an efflux pump by which they can resist the toxic effects of acetic acid. In this study, the efflux pump of Acetobacter aceti IFO 3283 was examined using intact cells and membrane vesicles. The accumulation of acetic acid/acetate in intact cells was increased by the addition of a proton uncoupler and/or cyanide, suggesting the presence of an energy-dependent efflux system. To confirm this, right-side-out and inside-out membrane vesicles were prepared from A. aceti IFO 3283, and the accumulation of acetic acid/acetate in the vesicles was examined. Upon the addition of a respiratory substrate, the accumulation of acetic acid/acetate in the right-side-out vesicles was largely decreased, while its accumulation was very much increased in the inside-out vesicles. These respiration-dependent phenomena observed in both types of membrane vesicles were all sensitive to a proton uncoupler. Acetic acid/acetate uptake in the inside-out membrane vesicles was dependent not on ATP but on the proton motive force. Furthermore, uptake was shown to be rather specific for acetic acid and to be pH dependent, because higher uptake was observed at lower pH. Thus, A. aceti IFO 3283 possesses a proton motive force-dependent efflux pump for acetic acid. PMID:15968043

Matsushita, Kazunobu; Inoue, Taketo; Adachi, Osao; Toyama, Hirohide

2005-01-01

287

Propionate stimulates pyruvate oxidation in the presence of acetate.  

PubMed

Flux through pyruvate dehydrogenase (PDH) in the heart may be reduced by various forms of injury to the myocardium, or by oxidation of alternative substrates in normal heart tissue. It is important to distinguish these two mechanisms because imaging of flux through PDH based on the appearance of hyperpolarized (HP) [(13)C]bicarbonate derived from HP [1-(13)C]pyruvate has been proposed as a method for identifying viable myocardium. The efficacy of propionate for increasing PDH flux in the setting of PDH inhibition by an alternative substrate was studied using isotopomer analysis paired with exams using HP [1-(13)C]pyruvate. Hearts from C57/bl6 mice were supplied with acetate (2 mM) and glucose (8.25 mM). (13)C NMR spectra were acquired in a cryogenically cooled probe at 14.1 Tesla. After addition of hyperpolarized [1-(13)C]pyruvate, (13)C NMR signals from lactate, alanine, malate, and aspartate were easily detected, in addition to small signals from bicarbonate and CO2. The addition of propionate (2 mM) increased appearance of HP [(13)C]bicarbonate >30-fold without change in O2 consumption. Isotopomer analysis of extracts from the freeze-clamped hearts indicated that acetate was the preferred substrate for energy production, glucose contribution to energy production was minimal, and anaplerosis was stimulated in the presence of propionate. Under conditions where production of acetyl-CoA is dominated by the availability of an alternative substrate, acetate, propionate markedly stimulated PDH flux as detected by the appearance of hyperpolarized [(13)C]bicarbonate from metabolism of hyperpolarized [1-(13)C]pyruvate. PMID:25320331

Purmal, Colin; Kucejova, Blanka; Sherry, A Dean; Burgess, Shawn C; Malloy, Craig R; Merritt, Matthew E

2014-10-15

288

Wendler F., Meister F., Wawro D., Wesolowska E., Ciechaska D., Saake B., Puls J., Le Moigne N., Navard P.; Polysaccharide Blend Fibres Formed from NaOH, N-Methylmorpholine-N-oxide and 1-Ethyl-3-methylimidazolium acetate. FIBRES & TEXTILES in Eastern Europ  

E-print Network

-methylimidazolium acetate. FIBRES & TEXTILES in Eastern Europe 2010, Vol. 18, No. 2 (79) pp. 21-30. 21, Thuringian Institute for Textile and Plastics Research, Rudolstadt, Germany, E-mail: wendler possible for all three solvents. The textile-physical properties of the blend fibres were slightly

Paris-Sud XI, Université de

289

[Histrelin acetate--the first once yearly LHRH agonist].  

PubMed

Long-acting synthetic luteinising hormone-releasing hormone agonists have become the mainstay for androgen-deprivation therapy, because they avoid the physical and psychological discomfort associated with orchidectomy and lack the potential cardiotoxicity associated with estrogens such as diethylstilbestrol. Currently available luteinising hormone-releasing hormone agonist analogues include leuprolide, goserelin, triptorelin, degarelix and buserelin were administered as either intramuscular or subcutaneous depot injections on a 1, 2, 3 or 6 months basis. Histrelin acetate is the first long-acting luteinising hormone-releasing hormone agonist available as a once-yearly subcutaneous implant. PMID:22165080

Altarac, Silvio

2011-01-01

290

2-Amino-5-chloro-pyridinium trifluoro-acetate.  

PubMed

The asymmetric unit of the title salt, C(5)H(6)ClN(2) (+)·C(2)F(3)O(2) (-), contains two independent 2-amino-5-chloro-pyridinium cations and two independent trifluoro-acetate anions. The F atoms of both anions are disordered over two sets of positions, with occupancy ratios of 0.672?(12):0.328?(12) and 0.587?(15):0.413?(15). In the crystal, the cations and anions are linked via N-H?O and C-H?O hydrogen bonds, forming a two-dimensional network parallel to (001). PMID:21580623

Hemamalini, Madhukar; Fun, Hoong-Kun

2010-01-01

291

Synthesis and Decarboxylative Coupling of Sulfonyl Acetic Esters  

E-print Network

, the anion is stabilized and that the pK a ’s are generally 32 or lower for the corresponding conjugate acid. 22 This seems to be the upper limit of where the barrier for decarboxylation becomes insurmountable and the rate of DCA becomes too slow... (DCA) of sulfones by looking at the simple unsubstituted allyl ester of ?-sulfonyl acetic acid, synthesized via a DCC/DMAP coupling, in the presence of a Pd catalyst. 29 First we screened solvents (Table 1.1) and observed, in every solvent tried...

Weaver, Jimmie Dean

2010-04-28

292

Kinetic Modeling of Esterification of Ethylene Glycol with Acetic Acid  

SciTech Connect

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

Yadav, Vishnu P.; Maity, Sunil K. [Department of Chemical Engineering, Indian Institute of Technology, Hyderabad, Ordnance Factory Estate, Yeddumailiram-502205, Andhra Pradesh (India); Mukherjee, Rudra Palash [Department of Chemical Engineering, National Institute of Technology, Durgapur, Mahatma Gandhi Avenue, Durgapur-713209, West Bengal (India); Bantraj, Kandi [Department of Chemical Engineering, National Institute of Technology, Rourkela-769008, Orissa (India)

2010-10-26

293

Microbial community of acetate utilizing denitrifiers in aerobic granules  

Microsoft Academic Search

The aerobic sludge granules cultivated at high organic loading rates could effectively convert 100–700 mg l?1 nitrite to nitrogen gas with 400 or 1,200 mg l?1 dosed acetate. The denitrifying microbial community structure of the so-cultivated granules was investigated by 16S rRNA\\u000a gene sequences and localized using fluorescence in situ hybridization (FISH). The 16S rRNA gene phylotypes in the clone library\\u000a and FISH probes

Sunil S. Adav; Duu-Jong Lee; J. Y. Lai

2010-01-01

294

Phonon transport in an initially twisted polyvinyl acetate nanofiber  

NASA Astrophysics Data System (ADS)

A reduction in phonon thermal conductivity enhances thermoelectric performance. One method to accomplish this is by applying mechanical stress to a nanostructure. We consider an initially twisted 20 nm polyvinyl acetate nanofiber undergoing torsion. Our analytical method uses the continuum approach of Mooney's model. Torsion modifies the phonon dispersion. Angles of twist between 45° and 70° reduce the averaged phonon group velocity and the phonon thermal conductivity but when these angles are increased further, this conductivity increases. This suggests a phonon engineering approach to tune the thermal conductivity of nanomaterials.

Liangruksa, Monrudee; Puri, Ishwar K.

2013-05-01

295

Prednisolone acetate-eluting novel biodegradable vascular stents for implantation  

E-print Network

25.10.2006 GPEN 2006 October 25-27 University of Kansas, Lawrence 1 PREDNISOLONE ACETATE-ELUTING NOVEL BIODEGRADABLE VASCULAR STENTS FOR IMPLANTATION Pharm. (M.Sc.) Can Sarisozen Assist. Prof. Dr. Betul Arica, Prof.Dr. Sema Calis, Prof.Dr. A... ve R e l ease S1 S2 S3 S4 Microsphere IncorporatedPLGA (50:50)S4 PA IncorporatedPLGA (50:50)S3 Microsphere IncorporatedPLGA (75:25)S2 PA IncorporatedPLGA (75:25)S1 PA or MicrospheresPolymerFormulation Code 25.10.2006 GPEN 2006 October 25-27 University...

Sarisozen, Can

2006-10-25

296

Effects of electron beam irradiation of cellulose acetate cigarette filters  

NASA Astrophysics Data System (ADS)

A method to reduce the molecular weight of cellulose acetate used in cigarette filters by using electron beam irradiation is demonstrated. Radiation levels easily obtained with commercially available electron accelerators result in a decrease in average molecular weight of about six-times with no embrittlement, or significant change in the elastic behavior of the filter. Since a first step in the biodegradation of cigarette filters is reduction in the filter material's molecular weight this invention has the potential to allow the production of significantly faster degrading filters.

Czayka, M.; Fisch, M.

2012-07-01

297

13C6-[Benzene Ring]-Indole-3-Acetic Acid  

PubMed Central

Indole-3-acetic acid (IAA) labeled with 13C in the six carbons of the benzene ring is described for use as an internal standard for quantitative mass spectral analysis of IAA by gas chromatography/selected ion monitoring. [13C6]IAA was compared to the available deuterium labeled compounds and shown to offer the advantages of nonexchangeability of the isotope label, high isotopic enrichment, and chromatographic properties identical to that of the unlabeled compound. The utility of [13C6]IAA for measurement of endogenous IAA levels was demonstrated by analysis of IAA in Lemna gibba G-3. PMID:16664570

Cohen, Jerry D.; Baldi, Bruce G.; Slovin, Janet Pernise

1986-01-01

298

A Specialized Citric Acid Cycle Requiring Succinyl-Coenzyme A (CoA):Acetate CoA-Transferase (AarC) Confers Acetic Acid Resistance on the Acidophile Acetobacter aceti  

Microsoft Academic Search

Microbes tailor macromolecules and metabolism to overcome specific environmental challenges. Acetic acid bacteria perform the aerobic oxidation of ethanol to acetic acid and are generally resistant to high levels of these two membrane-permeable poisons. The citric acid cycle (CAC) is linked to acetic acid resistance in Acetobacter aceti by several observations, among them the oxidation of acetate to CO2 by

Elwood A. Mullins; Julie A. Francois; T. Joseph Kappock

2008-01-01

299

Transport Parameters in a Porous Cellulose Acetate Membrane  

PubMed Central

The transport parameters of a cellulose acetate membrane prepared from a mixture of cellulose acetate, formamide, and acetone, 25:25:50 by weight, were studied. The membrane consists of a thin, porous layer, the skin, in series with a thick, highly porous layer, the coarse support. In the skin the diffusional permeability coefficient, ?, of a number of small amides and alcohols depends critically upon the partition coefficient, Ks, the size of the molecule, and the apparent hydrogen-bonding ability, Ns, of the solute. These observations are in general agreement with our earlier conclusions on the properties of nonporous membranes. On the other hand, the corrected reflection coefficient, ?', is not a very sensitive function of either Ns or Ks taken separately. The correlation between ?' and molecular diameter is reasonably good; however, it is much improved when both Ns and Ks are taken into consideration. Isotope interaction was also studied in the present preparation and was found to provide only a small (5–8%) contribution to the diffusional permeability coefficient of ethylene glycol. The contribution of solute-water friction was found to be less than 24% of the total solute friction. PMID:5410490

DiPolo, R.; Sha'afi, R. I.; Solomon, A. K.

1970-01-01

300

The effect of vinyl acetate in acetoclastic methanogenesis.  

PubMed

The influence of vinyl acetate (VA) in the methanogenesis was evaluated, by using an upflow anaerobic sludge blanket reactor of 1.5L. The reactor was operated at 33.5 g/L volatile suspended solids to 30±2 °C, a hydraulic residence time of 1 day, an organic loading rate of 1 kgCOD/m3/d of two different mixtures of VA and glucose. The VA was methanized to 81% when its proportion was of 10% into reactor loading rate, when VA proportion increased to 25%, the methane production rate decreased to 62% and the acetate production rate increased almost 8 times. These results indicated that VA was only hydrolyzed and glucose was not used as a co-substrate. The effect of glucose on VA methanogenic degradation was evaluated through batch reactors of 60 mL, concluding that the glucose supported the methanogenesis without favoring the VA elimination. On the other hand, the results of the sludge from the reactor in the presence of VA demonstrated that VA caused an irreversibly inhibition of acetoclastic methanogenesis when the anaerobic sludge was exposed to this compound. PMID:20933387

Durán, U; Gómez, J; Monroy, O; Ramírez, F

2011-01-01

301

Comparison of acetate utilization among strains of an aceticlastic methanogen, Methanothrix soehngenii  

SciTech Connect

Methane fermentation has been widely used as a waste-water treatment system because of the low consumption of energy, low level of sludge production, and recovery of methane as a source of energy. In this system, acetate is the precursor for about 70% of the methane produced during the anaerobic digestion of organic compounds, and the decarboxylation of acetate is considered to be the rate-limiting step in methane fermentation. The kinetics of acetate utilization by concentrated suspensions of cells was examined in five strains of Methanothrix soehngenii. The rate of acetate utilization by all strains was dependent on the initial acetate concentration and followed simple Michaelis-Menten kinetics. The ability to utilize acetate differed among the various strains of M. soehngenii and was highest in the strain designated MTAS.

Ohtsubo, Sadami; Demizu, Kazuhiro; Kohno, Shuhei; Miura, Isao (TOTO Ltd., Kokurakitaku (Japan)); Ogawa, Takahira; Fukuda, Hideo (Kumamoto Inst. of Tech. (Japan))

1992-02-01

302

Development and Characterization of Poly(1-vinylpyrrolidone-co-vinyl acetate) Copolymer Based Polymer Electrolytes  

PubMed Central

Gel polymer electrolytes (GPEs) are developed using poly(1-vinylpyrrolidone-co-vinyl acetate) [P(VP-co-VAc)] as the host polymer, lithium bis(trifluoromethane) sulfonimide [LiTFSI] as the lithium salt and ionic liquid, and 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide [EMImTFSI] by using solution casting technique. The effect of ionic liquid on ionic conductivity is studied and the optimum ionic conductivity at room temperature is found to be 2.14?×?10?6?S?cm?1 for sample containing 25?wt% of EMImTFSI. The temperature dependence of ionic conductivity from 303?K to 353?K exhibits Arrhenius plot behaviour. The thermal stability of the polymer electrolyte system is studied by using thermogravimetric analysis (TGA) while the structural and morphological properties of the polymer electrolyte is studied by using Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction analysis (XRD), respectively.

Sa'adun, Nurul Nadiah; Subramaniam, Ramesh; Kasi, Ramesh

2014-01-01

303

Toxicokinetics and Oral Bioavailability of Halogenated Acetic Acids Mixtures in Naive and GSTzeta-Depleted Rats  

Microsoft Academic Search

Pharmacokinetics of halogenated acetic acid (HAA) mixtures in native and GSTzeta depleted rats was investigated. Rats were administered orally or i.v. to Mixture-1 (monobromo- dichloro-, chlorodibromo-, tribromo- acetic acids) or Mixture-2 (bromochloro-, dibromo-, trichloro- bromodichloro- acetic acids) at a dose of 25 ?mol\\/kg HAA and blood samples collected up to 36 h. GSTzeta depleted rats were also orally dosed with

Shakil A. Saghir; Irvin R. Schultz

2005-01-01

304

Acetate and Formate Stress: Opposite Responses in the Proteome of Escherichia coli  

Microsoft Academic Search

Acetate and formate are major fermentation products of Escherichia coli. Below pH 7, the balance shifts to lactate; an oversupply of acetate or formate retards growth. E. coli W3110 was grown with aeration in potassium-modified Luria broth buffered at pH 6.7 in the presence or absence of added acetate or formate, and the protein profiles were compared by two-dimensional sodium

CHRISTOPHER KIRKPATRICK; LISA M. MAURER; NIKKI E. OYELAKIN; YULIYA N. YONCHEVA; RUSSELL MAURER; JOAN L. SLONCZEWSKI

2001-01-01

305

Effects of Acetic Acid Pretreatment and Hot Air Drying on Resistance of Salmonella on Cabbage Slices  

Microsoft Academic Search

The heat resistance of Salmonella anatum inoculated onto the surface of cabbage slices as affected by acetic acid pretreatment (0.5–1.5% v\\/v) and hot air drying at 50–60°C was investigated. Approximately 1.5 log10 of Salmonella numbers was reduced after soaking the vegetables in acetic acid solution. The inhibitory effect of acetic acid on the bacteria was more pronounced during drying. The heat

Naphaporn Chiewchan; Pornpen Morakotjinda

2009-01-01

306

Sodium acetate infusion in critically ill trauma patients for hyperchloremic acidosis  

Microsoft Academic Search

Introduction  Sodium acetate has been shown to cause hemodynamic instability when used as a hemodialysis buffer. The pattern of hemodynamic\\u000a response to injury will be evaluated between those who received sodium acetate and those who did not.\\u000a \\u000a \\u000a The primary purpose of the study is to analyze the effect of sodium acetate on hemodynamic parameters. Secondarily we looked\\u000a at the effects on

Andrew McCague; Mira Dermendjieva; Ryan Hutchinson; David T Wong; Nguyen Dao

2011-01-01

307

Process for the preparation of protected 3-amino-1,2-dihydroxypropane acetal and derivatives thereof  

DOEpatents

A process for producing protected 3-amino-1,2-dihydroxypropane acetal, particularly in chiral forms, for use as an intermediate in the preparation of various 3-carbon compounds which are chiral. In particular, the present invention relates to the process for preparation of 3-amino-1,2-dihydroxypropane isopropylidene acetal. The protected 3-amino-1,2-dihydroxypropane acetal is a key intermediate to the preparation of chiral 3-carbon compounds which in turn are intermediates to various pharmaceuticals.

Hollingsworth, Rawle I. (Haslett, MI); Wang, Guijun (East Lansing, MI)

2000-01-01

308

Electron transport in acetate-grown Methanosarcina acetivorans  

PubMed Central

Background Acetate is the major source of methane in nature. The majority of investigations have focused on acetotrophic methanogens for which energy-conserving electron transport is dependent on the production and consumption of H2 as an intermediate, although the great majority of acetotrophs are unable to metabolize H2. The presence of cytochrome c and a complex (Ma-Rnf) homologous to the Rnf (Rhodobacter nitrogen fixation) complexes distributed in the domain Bacteria distinguishes non-H2-utilizing Methanosarcina acetivorans from H2-utilizing species suggesting fundamentally different electron transport pathways. Thus, the membrane-bound electron transport chain of acetate-grown M. acetivorans was investigated to advance a more complete understanding of acetotrophic methanogens. Results A component of the CO dehydrogenase/acetyl-CoA synthase (CdhAE) was partially purified and shown to reduce a ferredoxin purified using an assay coupling reduction of the ferredoxin to oxidation of CdhAE. Mass spectrometry analysis of the ferredoxin identified the encoding gene among annotations for nine ferredoxins encoded in the genome. Reduction of purified membranes from acetate-grown cells with ferredoxin lead to reduction of membrane-associated multi-heme cytochrome c that was re-oxidized by the addition of either the heterodisulfide of coenzyme M and coenzyme B (CoM-S-S-CoB) or 2-hydoxyphenazine, the soluble analog of methanophenazine (MP). Reduced 2-hydoxyphenazine was re-oxidized by membranes that was dependent on addition of CoM-S-S-CoB. A genomic analysis of Methanosarcina thermophila, a non-H2-utilizing acetotrophic methanogen, identified genes homologous to cytochrome c and the Ma-Rnf complex of M. acetivorans. Conclusions The results support roles for ferredoxin, cytochrome c and MP in the energy-conserving electron transport pathway of non-H2-utilizing acetotrophic methanogens. This is the first report of involvement of a cytochrome c in acetotrophic methanogenesis. The results suggest that diverse acetotrophic Methanosarcina species have evolved diverse membrane-bound electron transport pathways leading from ferredoxin and culminating with MP donating electrons to the heterodisulfide reductase (HdrDE) for reduction of CoM-S-S-CoB. PMID:21781343

2011-01-01

309

Clinical development of two innovative pharmaceutical forms of leuprorelin acetate  

PubMed Central

Objectives: Two innovative pharmaceutical forms of leuprorelin acetate have been developed as 1-month and 3-month implants for the treatment of advanced hormone-dependent prostate cancer. These products contain active substance dispersed homogeneously in a biodegradable polymer. Here we present the key results from the clinical development of these slow-release implant formulations of leuprorelin. Methods: Two therapeutic studies of the 1-month implant were performed: a randomized, controlled study comparing the leuprorelin implant with leuprorelin prolonged-release microspheres (Enantone) as the active control; and a single-arm study of the leuprorelin implant. For the 3-month implant, four therapeutic studies were performed: a randomized, controlled study comparing the leuprorelin implant with leuprorelin prolonged-release microspheres (Trenantone) as the active control; a single-arm study of the leuprorelin implant; and two long-term studies with the 3-month implant administered twice, either 12 or 16 weeks apart. A pooled analysis of data from the comparator-controlled and single-arm studies of the 3-month implant was also conducted. The main inclusion criterion for all studies was histologically confirmed advanced prostate cancer, with primary endpoints based around successful testosterone suppression (?0.5 ng/ml). Results: In the comparator-controlled studies, both implants were as effective as the microspheres for achieving successful testosterone suppression and normalization of prostate-specific antigen (PSA) levels. Data from the single-arm and long-term studies were consistent with those from the comparator-controlled studies. In the pooled analysis, significantly more patients treated with the 3-month implant achieved successful testosterone suppression compared with the comparator (p ? 0.01). The safety profile of the implants in the comparator-controlled studies was similar to that of the prolonged-release microsphere formulation, and consistent with that of the luteinizing hormone-releasing hormone agonist class. Conclusions: The innovative 1-month and 3-month implants of leuprorelin acetate are at least as effective as leuprorelin acetate prolonged-release microspheres for achieving successful testosterone suppression and normalization of PSA in men with advanced hormone-dependent prostate cancer, with a comparable safety profile. PMID:23372606

Geiges, Goetz; Schapperer, Elisabeth; Thyroff-Friesinger, Ursula; Engert, Zoltan Vendel

2013-01-01

310

Physiology and Genetics of Biogenic Methane-Production from Acetate  

SciTech Connect

Biomass conversion catalyzed by methanogenic consortia is a widely available, renewable resource for both energy production and waste treatment. The efficiency of this process is directly dependent upon the interaction of three metabolically distinct groups of microorganisms; the fermentative and acetogenic Bacteria and the methanogenic Archaea. One of the rate limiting steps in the degradation of soluble organic matter is the dismutation of acetate, a predominant intermediate in the process, which accounts for 70 % or more of the methane produced by the methanogens. Acetate utilization is controlled by regulation of expression of carbon monoxide dehydrogensase (COdh), which catalyzes the dismutation of acetate. However, physiological and molecular factors that control differential substrate utilization have not been identified in these Archaea. Our laboratory has identified sequence elements near the promoter of the gene (cdh) encoding for COdh and we have confirmed that these sequences have a role in the in vivo expression of cdh. The current proposal focuses on identifying the regulatory components that interact with DNA and RNA elements, and identifying the mechanisms used to control cdh expression. We will determine whether expression is controlled at the level of transcription or if it is mediated by coordinate interaction of transcription initiation with other processes such as transcription elongation rate and differential mRNA stability. Utilizing recently sequenced methanosarcinal genomes and a DNA microarray currently under development genes that encode regulatory proteins and transcription factors will be identified and function confirmed by gene disruption and subsequent screening on different substrates. Functional interactions will be determined in vivo by assaying the effects of gene dosage and site-directed mutagenesis of the regulatory gene on the expression of a cdhAÂ?::lacZ operon fusion. Results of this study will reveal whether this critical catabolic pathway is controlled by mechanisms similar to those employed by the Bacteria and Eukarya, or by a regulatory paradigm that is unique to the Archaea. The mechanism(s) revealed by this investigation will provide insight into the regulatory strategies employed by the aceticlastic methanogenic Archaea to efficiently direct carbon and electron flow in anaerobic consortia during fermentative processes.

Sowers, Kevin R

2013-04-04

311

Isotope fractionation during the anaerobic consumption of acetate by methanogenic and sulfate-reducing microorganisms  

NASA Astrophysics Data System (ADS)

During the anaerobic degradation of organic matter in anoxic sediments and soils acetate is the most important substrate for the final step in production of CO2 and/or CH4. Sulfate-reducing bacteria (SRB) and methane-producing archaea both compete for the available acetate. Knowledge about the fractionation of 13C/12C of acetate carbon by these microbial groups is still limited. Therefore, we determined carbon isotope fractionation in different cultures of acetate-utilizing SRB (Desulfobacter postgatei, D. hydrogenophilus, Desulfobacca acetoxidans) and methanogens (Methanosarcina barkeri, M. acetivorans). Including literature values (e.g., Methanosaeta concilii), isotopic enrichment factors (epsilon) ranged between -35 and +2 permil, possibly involving equilibrium isotope effects besides kinetic isotope effects. The values of epsilon were dependent on the acetate-catabolic pathway of the particular microorganism, the methyl or carboxyl position of acetate, and the relative availability or limitation of the substrate acetate. Patterns of isotope fractionation in anoxic lake sediments and rice field soil seem to reflect the characteristics of the microorganisms actively involved in acetate catabolism. Hence, it might be possible using environmental isotopic information to determine the type of microbial metabolism converting acetate to CO2 and/or CH4.

Gövert, D.; Conrad, R.

2009-04-01

312

[Abiraterone acetate (AA): current guidelines of prescription of abiraterone].  

PubMed

Abiraterone acetate (AA) is a selective inhibitor of cytochrom p450 (CYP)17 which is required for androgen biosynthesis, and can block the androgens synthesis by testicles, surrenals and intratumoral secretion. In phase I and II studies in patients with prostate cancer, therapy with AA 250-2000 ?mg once daily demonstrated reductions in prostate specific antigen (PSA), and/or circulating tumor cells (CTCs). In two large phase III trials in patients with metastatic castration resistant prostate cancer (CRPC) in post-docetaxel and pre-docetaxel setting, AA plus prednisone compared with placebo plus prednisone demonstrated a significant superior overall survival in post-docetaxel setting, and a superior radiological PFS in pre-docetaxel setting. Based of these results, AA is approved in metastatic CRPC patients in post-docetaxel setting or pre-docetaxel setting in 2013. PMID:24793632

Boissier, Emilie; Loriot, Yohann; Vignot, Stéphane; Massard, Christophe

2014-04-01

313

Degarelix acetate for the treatment of prostate cancer.  

PubMed

Pharmacological methods of achieving androgen deprivation for the treatment of prostate cancer have evolved. New strategies are focusing on avoidance of the undesirable effects of testosterone surges or flares associated with the initial stages of gonadotropin-releasing hormone (GnRH) agonists and the significant histamine-mediated side effects that can be associated with GnRH antagonists. Degarelix acetate (Firmagon; Ferring Pharmaceuticals) is a third-generation GnRH antagonist that has been shown to produce a significantly more rapid medical castration (without testosterone surge) and prostate-specific antigen response compared with GnRH agonists. The safety profile is comparable to GnRH agonists and anaphylactic reactions have not been reported. Degarelix is currently available as a 1-month subcutaneous injection and has been approved for the treatment of advanced prostate cancer. PMID:20069136

Klotz, Laurence

2009-10-01

314

2-Amino-4-methyl-pyridinium trifluoro-acetate.  

PubMed

The asymmetric unit of the title compound, C(6)H(9)N(2) (+)·C(2)F(3)O(2) (-), contains two independent 2-amino-4-methyl-pyridinium cations and two independent trifluoro-acetate anions. The F atoms of both anions are disordered over two sets of sites, with site occupancies of 0.50?(3) and 0.50?(3) in one of the anions, and 0.756?(9) and 0.244?(9) in the other. In the crystal, the cations and anions are linked into chains along the b axis by N-H?O hydrogen bonds and these chains are cross-linked by C-H?O hydrogen bonds, forming a two-dimensional network lying parallel to (101). The crystal structure is further stabilized by ?-? inter-actions between the pyridinium rings [centroid-centroid distances = 3.5842?(13) and 3.5665?(16)?Å]. PMID:21580622

Hemamalini, Madhukar; Fun, Hoong-Kun

2010-01-01

315

Purification and characterization of an alkaline protease from Acetes chinensis  

NASA Astrophysics Data System (ADS)

An alkaline protease from Acetes chinensis was purified and characterized in this study. The steps of purification include ammonium sulfate precipitation, ion-exchange chromatography with Q-sepharose Fast Flow, gel filtration chromatography with S300 and the second ion-exchange chromatography with Q-sepharose Fast Flow. The protease was isolated and purified, which was present and active on protein substrates (azocasein and casein). The specific protease activity was 17.15 folds and the recovery was 4.67. The molecular weight of the protease was estimated at 23.2 kD by SDS-PAGE. With azocasein as the susbstrate, the optimal temperature was 55°C and the optimal pH value was 5.5. Ion Ca2+ could enhance the proteolytic activity of the protease, while Cu2+, EDTA and PMSF could inhibit its activity.

Xu, Jiachao; Liu, Xin; Li, Zhaojie; Xu, Jie; Xue, Changhu; Gao, Xin

2005-07-01

316

Ignition of magnetic deflagration in Mn12 acetate  

NASA Astrophysics Data System (ADS)

We study the conditions for the ignition of two types of magnetic avalanches in the molecular magnet Mn12-acetate corresponding to the major species and a fast-relaxing minor species. The minor component, which has a lower anisotropy barrier, exists in these crystals at the level of 5-7%. The ignition temperatures are measured using small (30 x30 ?m^2) Ge thermometers. In addition, the magnetization dynamics are measured using an array of Hall sensors of comparable size. Various aspects of the ignition will be discussed, including: the reduction of the ignition threshold due to quantum tunneling, the catalytic effect of the minor species, and the shift of the ignition point as a function of external magnetic field. The work at City College was supported by NSF grant DMR-00451605. E. Z. acknowledges the support of the Israel Ministry of Science, Culture and Sports. Support for G. C. was provided by NSF grant CHE-0414555.

McHugh, Sean; Jaafar, R.; Sarachik, M. P.; Myasoedov, Y.; Finkler, A.; Shtrikman, H.; Zeldov, E.; Bagai, R.; Christou, G.

2008-03-01

317

Glatiramer acetate in the treatment of multiple sclerosis  

PubMed Central

Glatiramer acetate is an immunomodulating drug used in the treatment of multiple sclerosis. It consists of a copolymer of amino acid residues in the same stoichiometric proportions as in myelin basic protein. Its mechanism of action is not entirely known and is probably multifaceted, with deletion of some immune cell populations and stimulation of others in these patients. Some mechanisms involve neuroprotectant effects. There is ample evidence of its efficacy in relapsing-remitting disease, using both clinical and imaging measures of disease activity, and in this paper we review the clinical and basic studies of this drug. Finally we discuss how some of its neuroprotectant effects may be useful in neurodegeneration such as is seen in more advanced cases of multiple sclerosis and other diseases such as amyotrophic lateral sclerosis and Parkinson’s disease. PMID:19300558

Tselis, Alex; Khan, Omar; Lisak, Robert P

2007-01-01

318

[The weakest link: medroxyprogesterone acetate in pig feed].  

PubMed

Medroxyprogesterone acetate (MPA)-contaminated feed arrested the onset of farrowing, and induced post-lactational anoestrus in sows. Sixty percent of the sows developed cystic ovaries after weaning following exposure to pharmaceutical waste of MPA in glucose syrup. This waste ended up in acidified feed of by-products of a sow farm, and proved to be the cause of the disorders. Analysis by thin layer chromatography and Gas Chromatography/Mass Spectrometry of renal fat from 10 slaughter sows demonstrated residues of 2.5-8 ppb of MPA. Within the European Union use of MPA is illegal as growth promoter in production animals, and therefore MPA-exposed farms were placed under official control by the general inspection service. Clinical signs and diagnostic procedures of the initial case are presented and the role of the veterinary practitioner in detecting potential food safety hazards is discussed. PMID:12244854

van Leengoed, L; Kluivers, M; Herbes, R; Langendijk, P; Stephany, R; van den Berg, M; Seinen, W; Grinwis, G; van der Lugt, J; Meulders, F; Geudeke, T; Verheijden, J

2002-09-01

319

Preparation and characterization of novel oxidized cellulose acetate methyl esters.  

PubMed

In this paper, we report the preparation of oxidized cellulose acetate methyl esters (OCAM) from OCA (OC14A: carboxylic acid content 10.6% (w/w), degree of acetyl group substitution: 1.89; OC21A: carboxylic acid content 15.7% (w/w), degree of acetyl group substitution: 1.70) by treatment with methanol at room temperature using 4-dimethylaminopyridine (DMAP) as a catalyst and dicyclohexylcarbodiimide (DCC) as a coupling agent. The new polymers were characterized by Fourier-transform infrared (FT-IR) and (1)H and (13)C nuclear magnetic resonance spectroscopies, carboxylic acid content determination, moisture sorption isotherms, intrinsic viscosity, and powder X-ray diffractometry. The new polymers are amorphous powders. It is practically insoluble in water but show solubility in a range of organic solvents. PMID:22944406

Yang, D; Kumar, V

2012-11-01

320

Acetic Acid bacteria: physiology and carbon sources oxidation.  

PubMed

Acetic acid bacteria (AAB) are obligately aerobic bacteria within the family Acetobacteraceae, widespread in sugary, acidic and alcoholic niches. They are known for their ability to partially oxidise a variety of carbohydrates and to release the corresponding metabolites (aldehydes, ketones and organic acids) into the media. Since a long time they are used to perform specific oxidation reactions through processes called "oxidative fermentations", especially in vinegar production. In the last decades physiology of AAB have been widely studied because of their role in food production, where they act as beneficial or spoiling organisms, and in biotechnological industry, where their oxidation machinery is exploited to produce a number of compounds such as l-ascorbic acid, dihydroxyacetone, gluconic acid and cellulose. The present review aims to provide an overview of AAB physiology focusing carbon sources oxidation and main products of their metabolism. PMID:24426139

Mamlouk, Dhouha; Gullo, Maria

2013-12-01

321

Inflammatory cells' role in acetic acid-induced colitis  

PubMed Central

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

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

2014-01-01

322

Recent advances in nitrogen-fixing acetic acid bacteria.  

PubMed

Nitrogen is an essential plant nutrient, widely applied as N-fertilizer to improve yield of agriculturally important crops. An interesting alternative to avoid or reduce the use of N-fertilizers could be the exploitation of plant growth-promoting bacteria (PGPB), capable of enhancing growth and yield of many plant species, several of agronomic and ecological significance. PGPB belong to diverse genera, including Azospirillum, Azotobacter, Herbaspirillum, Bacillus, Burkholderia, Pseudomonas, Rhizobium, and Gluconacetobacter, among others. They are capable of promoting plant growth through different mechanisms including (in some cases), the biological nitrogen fixation (BNF), the enzymatic reduction of the atmospheric dinitrogen (N(2)) to ammonia, catalyzed by nitrogenase. Aerobic bacteria able to oxidize ethanol to acetic acid in neutral or acid media are candidates of belonging to the family Acetobacteraceae. At present, this family has been divided into ten genera: Acetobacter, Gluconacetobacter, Gluconobacter, Acidomonas, Asaia, Kozakia, Saccharibacter, Swaminathania, Neoasaia, and Granulibacter. Among them, only three genera include N(2)-fixing species: Gluconacetobacter, Swaminathania and Acetobacter. The first N(2)-fixing acetic acid bacterium (AAB) was described in Brazil. It was found inside tissues of the sugarcane plant, and first named as Acetobacter diazotrophicus, but then renamed as Gluconacetobacter diazotrophicus. Later, two new species within the genus Gluconacetobacter, associated to coffee plants, were described in Mexico: G. johannae and G. azotocaptans. A salt-tolerant bacterium named Swaminathania salitolerans was found associated to wild rice plants. Recently, N(2)-fixing Acetobacter peroxydans and Acetobacter nitrogenifigens, associated with rice plants and Kombucha tea, respectively, were described in India. In this paper, recent advances involving nitrogen-fixing AAB are presented. Their natural habitats, physiological and genetic aspects, as well as their association with different plants and contribution through BNF are described as an overview. PMID:18177965

Pedraza, Raúl O

2008-06-30

323

Reversible acetylation regulates acetate and propionate metabolism in Mycobacterium smegmatis  

PubMed Central

Carbon metabolic pathways are important to the pathogenesis of Mycobacterium tuberculosis, the causative agent of tuberculosis. However, extremely little is known about metabolic regulation in mycobacteria. There is growing evidence for lysine acetylation being a mechanism of regulating bacterial metabolism. Lysine acetylation is a post-translational modification in which an acetyl group is covalently attached to the side chain of a lysine residue. This modification is mediated by acetyltransferases, which add acetyl groups, and deacetylases, which remove the acetyl groups. Here we set out to test whether lysine acetylation and deacetylation impact acetate metabolism in the model mycobacteria Mycobacterium smegmatis, which possesses 25 candidate acetyltransferases and 3 putative lysine deacetylases. Using mutants lacking predicted acetyltransferases and deacetylases we showed that acetate metabolism in M. smegmatis is regulated by reversible acetylation of acetyl-CoA synthetase (Ms-Acs) through the action of a single pair of enzymes: the acetyltransferase Ms-PatA and the sirtuin deacetylase Ms-SrtN. We also confirmed that the role of Ms-PatA in regulating Ms-Acs regulation depends on cAMP binding. We additionally demonstrated a role for Ms-Acs, Ms-PatA and Ms-SrtN in regulating the metabolism of propionate in M. smegmatis. Finally, along with Ms-Acs, we identified a candidate propionyl-CoA synthetase, Ms5404, as acetylated in whole-cell lysates. This work lays the foundation for studying the regulatory circuit of acetylation and deacetylation in the cellular context of mycobacteria. PMID:23813678

Hayden, Jennifer D.; Brown, Lanisha R.; Gunawardena, Harsha P.; Perkowski, Ellen F.; Chen, Xian

2013-01-01

324

Decreased microglial activation in MS patients treated with glatiramer acetate  

PubMed Central

Activated microglia are thought to be an important contributor to tissue damage in multiple sclerosis (MS). The level of microglial activation can be measured non-invasively using [11C]-R-PK11195, a radiopharmaceutical for positron emission tomography (PET). Prior studies have identified abnormalities in the level of [11C]-R-PK11195 uptake in patients with MS, but treatment effects have not been evaluated. Nine previously untreated relapsing-remitting MS patients underwent PET and magnetic resonance imaging (MRI) of the brain at baseline and after one year of treatment with glatiramer acetate. Parametric maps of [11C]-R-PK11195 uptake were obtained for baseline and post-treatment PET scans, and the change in [11C]-R-PK11195 uptake pre- to post-treatment was evaluated across the whole brain. Region of interest analysis was also applied to selected subregions. Whole brain [11C]-R-PK11195 binding potential per unit volume decreased 3.17% (95% CI: ?0.74%, ?5.53%) between baseline and one year (p = 0.018). A significant decrease was noted in cortical gray matter and cerebral white matter, and a trend towards decreased uptake was seen in the putamen and thalamus. The results are consistent with a reduction in inflammation due to treatment with glatiramer acetate, though a larger controlled study would be required to prove that association. Future research will focus on whether the level of baseline microglial activation predicts future tissue damage in MS and whether [11C]-R-PK11195 uptake in cortical gray matter correlates with cortical lesion load. PMID:22160466

Ratchford, John N.; Endres, Christopher J.; Hammoud, Dima A.; Pomper, Martin G.; Shiee, Navid; McGready, John; Pham, Dzung L.; Calabresi, Peter A.

2012-01-01

325

Sphagnum's coup de grace: Carbon flow to acetate in northern peatlands  

NASA Astrophysics Data System (ADS)

Isotopic estimates of the microbial pathway of methane formation in acidic northern peatlands conclude that methane is derived from the pathway of CO2 reduction, whereas, microbial incubation and genomic studies have identified an important role played by acetoclastic methanogens in similar acidic systems. We believe our first ever intramolecular acetate isotopic analyses from an acidic wetland in central Pennsylvania resolve the apparent conflicting pathway estimates by indicating that the isotopic and microbial incubation studies are consistent with each other and with a pathway of methane formation through acetate from an isotopically depleted autotrophic acetate source. Intramolecular acetate isotopic measurements allow us to estimate that as much as 1/3 of the acetate in acidic wetlands is derived from autotrophy. Given a simple case of glucose fermentation to acetate, carbon dioxide, and hydrogen, our acetate production pathway estimate requires that nearly all of the carbon products from fermentation must flow through the acetate pool. Our work confirms the prior hypothesis and prior observations that acetate is an important metabolic end product in northern acidic wetlands. Further, we hypothesize an alternative fate of acetate in peat porewaters that alludes to an ecological role of autotorophic acetogens and acetate oxidizers in creating the impermeable humified peat catotelm unique to sphagnum dominated systems. The diversion of carbon flow to from methane to acetate increases the organic acid production and we hypothesize that the net transport of dissolved fulvic acids into the catotelm allows coupled acetate oxidation and fulvic acid reduction. This process of acetate consumption would create a net addition of hydrophobic, amorphous, and therefore more impermeable organic carbon. We conclude that an ecological strategy of the sphagnum mosses may not simply be to decrease the pH of the environment to slow metabolism, but rather to force the microbial community in the catotelm toward the oxidation of acetate and the reduction of peat humus, thereby aiding production of the characteristic impermeable organic seal. The sensitivity of sphagnum ecosystems to external sources of alkalinity may prove to be an important control on the ancient flux of methane from peatlands and may be an important direction of continued research.

Thomas, B.; Arthur, M. A.; House, C.; Freean, K.

2008-12-01

326

Transports of acetate and haloacetate in Burkholderia species MBA4 are operated by distinct systems  

PubMed Central

Background Acetate is a commonly used substrate for biosynthesis while monochloroacetate is a structurally similar compound but toxic and inhibits cell metabolism by blocking the citric acid cycle. In Burkholderia species MBA4 haloacetate was utilized as a carbon and energy source for growth. The degradation of haloacid was mediated by the production of an inducible dehalogenase. Recent studies have identified the presence of a concomitantly induced haloacetate-uptake activity in MBA4. This uptake activity has also been found to transport acetate. Since acetate transporters are commonly found in bacteria it is likely that haloacetate was transported by such a system in MBA4. Results The haloacetate-uptake activity of MBA4 was found to be induced by monochloroacetate (MCA) and monobromoacetate (MBA). While the acetate-uptake activity was also induced by MCA and MBA, other alkanoates: acetate, propionate and 2-monochloropropionate (2MCPA) were also inducers. Competing solute analysis showed that acetate and propionate interrupted the acetate- and MCA- induced acetate-uptake activities. While MCA, MBA, 2MCPA, and butyrate have no effect on acetate uptake they could significantly quenched the MCA-induced MCA-uptake activity. Transmembrane electrochemical potential was shown to be a driving force for both acetate- and MCA- transport systems. Conclusions Here we showed that acetate- and MCA- uptake in Burkholderia species MBA4 are two transport systems that have different induction patterns and substrate specificities. It is envisaged that the shapes and the three dimensional structures of the solutes determine their recognition or exclusion by the two transport systems. PMID:23167477

2012-01-01

327

Balanophora spicata and Lupeol Acetate Possess Antinociceptive and Anti-Inflammatory Activities In Vivo and In Vitro  

PubMed Central

Aims of the present study were to investigate effects of Balanophora spicata (BS) on antinociception and anti-inflammation both in vivo and in vitro. Crude extract of BS inhibited vascular permeability induced by histamine, serotonin, bradykinin, and PGE2, but not by PAF. Furthermore, BS crude extract, different layers (n-hexane, ethyl acetate, n-butanol, and water layer), and lupeol acetate had significant antinociceptive and anti-inflammatory effects on acetic acid-induced abdominal writhing response, formalin-induced licking behavior, carrageenan-, and serotonin-induced paw edema. The n-hexane layer had the most effective potency among all layers (IC50: 67.33?mg/kg on writhing response; IC50s: 34.2?mg/kg and 21.29?mg/kg on the early phase and late phase of formalin test, resp.). Additionally, lupeol acetate which was isolated from the n-hexane layer of BS effectively inhibited the acetic acid-induced writhing response (IC50: 28.32?mg/kg), formalin-induced licking behavior (IC50: 20.95?mg/kg), NO production (IC50: 4.102??M), iNOS expression (IC50: 5.35??M), and COX2 expression (IC50: 5.13??M) in LPS-stimulated RAW 264.7 cells. In conclusion, BS has antinociceptive and anti-inflammatory effects which may be partially due to the inhibition of changes in vascular permeability induced by histamine, serotonin, bradykinin, and PGE2 and the attenuation of iNOS and COX-2 expression. PMID:23243439

Chen, Yuh-Fung; Ching, Chien; Wu, Tian-Shung; Wu, Chi-Rei; Hsieh, Wen-Tsong; Tsai, Huei-Yann

2012-01-01

328

Conductance of HCl, NaCl, Na acetate, and acetic acid in water-ethylene carbonate solvent mixtures at 25 and 40°C  

Microsoft Academic Search

The molar conductances of solutions of hydrochloric acid, sodium chloride, sodium acetate, and acetic acid were measured in water-ethylene carbonate (EC) solvent mixtures at 25 and 40°C. These solvents have dielectric constants higher than that of water. Four solvent compositions, in which the mole fraction (x2) of EC was 0.2, 0.4, 0.5, and 0.6, were studied at 25°C. For HCl

Barry R. Boerner; Roger G. Bates

1978-01-01

329

The fate of trenbolone acetate and melengestrol acetate after application as growth promoters in cattle: environmental studies.  

PubMed Central

The steroids trenbolone acetate (TbA) and melengestrol acetate (MGA) are licensed as growth promoters for farm animals in several meat-exporting countries. Although many studies have explored their safety for both animals and consumers, little is known about their fate after excretion by the animal. Our study aimed to determine the residues and degradation of trenbolone and MGA in solid dung, liquid manure, and soil. In animal experiments lasting 8 weeks, cattle were treated with TbA and MGA. Solid dung and, in case of trenbolone, liquid manure were collected and spread on maize fields after 4.5 and 5.5 months of storage, respectively. Determination of the hormone residues in all samples included extraction, clean-up (solid-phase extraction), separation of metabolites and interfering substances by HPLC (RP-18), and quantification by sensitive enzyme immunoassay. Procedures were validated by mass spectrometry (MS) methods. During storage of liquid manure the level of trenbolone decreased from 1,700 to 1,100 pg/g (17alpha-isomer), corresponding to a half-life of 267 days. Before storage, the concentrations in the dung hill ranged from 5 to 75 ng/g TbOH and from 0.3 to 8 ng/g MGA. After storage, levels up to 10 ng/g trenbolone, and 6 ng/g MGA were detected. In the soil samples trenbolone was traceable up to 8 weeks after fertilization, and MGA was detected even until the end of the cultivation period. The results show that these substances should be investigated further concerning their potential endocrine-disrupting activity in agricultural ecosystems. PMID:11713000

Schiffer, B; Daxenberger, A; Meyer, K; Meyer, H H

2001-01-01

330

Modification of wheat starch with succinic acid/acetic anhydride and azelaic acid/acetic anhydride mixtures I. Thermophysical and pasting properties.  

PubMed

The aim of this research was to investigate the influence of modification with succinic acid/acetic anhydride and azelaic acid/acetic anhydride mixtures on thermophysical and pasting properties of wheat starch. Starch was isolated from two wheat varieties and modified with mixtures of succinic acid and acetic anhydride, and azelaic acid and acetic anhydride in 4, 6 and 8 % (w/w). Thermophysical, pasting properties, swelling power, solubility and amylose content of modified starches were determined. The results showed that modifications with mixtures of afore mentioned dicarboxylic acids with acetic anhydride decreased gelatinisation and pasting temperatures. Gelatinisation enthalpy of Golubica starch increased, while of Srpanjka starch decreased by modifications. Retrogradation after 7 and 14 day-storage at 4 °C decreased after modifications of both starches. Maximum, hot and cold paste viscosity of both starches increased, while stability during shearing at high temperatures decreased. % setback of starches modified with azelaic acid/acetic anhydride mixture decreased. Swelling power and solubility of both starches increased by both modifications. PMID:25328203

Subari?, Drago; A?kar, Dur?ica; Babi?, Jurislav; Saka?, Nikola; Jozinovi?, Antun

2014-10-01

331

Megestrol acetate: Phase II study of a single daily administration in advanced breast cancer  

Microsoft Academic Search

Summary A new formulation of megestrol acetate, a semisynthetic oral progestin used in the hormonal treatment of breast cancer, allows the administration of 160 mg of the drug in a single daily dose. Sixty-nine postmenopausal patients with advanced breast cancer have been treated with this regimen: five patients received megestrol acetate as first-line treatment of their metastatic disease, while all

Paolo Pronzato; Fulvio Brema; Domenico Amoroso; Gianfilippo Bertelli; Pier Franco Conte; Maria Cristina Martini; Gisella Pastorino; Riccardo Rosso

1990-01-01

332

Acetate stimulates atmospheric CH4 oxidation by an alpine tundra Ann E. West, Steven K. Schmidt*  

E-print Network

Acetate stimulates atmospheric CH4 oxidation by an alpine tundra soil Ann E. West, Steven K CH4 by an alpine tundra soil. Acetate, formate, methanol, trimethylamine and yeast extract were; Jensen et al., 1998b). West and Schmidt (1998) demonstrated that, in a well-drained alpine tundra soil

Schmidt, Steven K.

333

Nanoporous layered silicate AMH-3/cellulose acetate nanocomposite membranes for gas separations  

E-print Network

. The exfoliated SAMH-3 flakes were used to form SAMH-3/cellulose acetate (CA) membranes. Their micro- structureNanoporous layered silicate AMH-3/cellulose acetate nanocomposite membranes for gas separations Wun are of interest because they can exploit the high aspect ratio of exfoliated selective flakes/layers to enhance

Nair, Sankar

334

Improved Fixation of Cellulose-Acetate Reverse-Osmosis Membrane for Scanning Electron Microscopy  

PubMed Central

Fixation of cellulose-acetate membranes with either glutaraldehyde-osmium tetroxide or glutaraldehyde-ruthenium tetroxide resulted in extensive electron beam damage. Beam damage was eliminated and the bacterial surface structure was preserved, however, when cellulose-acetate membranes were fixed with glutaraldehyderuthenium tetroxide and treated successively with thiocarbohydrazide and osmium tetroxide. Images PMID:16346735

Kutz, S. M.; Bentley, D. L.; Sinclair, N. A.

1985-01-01

335

Dilute Acetic Acid Exposure Enhances Electrolyte Leakage by Hydrilla verticillata and Potamogeton pectinatus Tubers  

Microsoft Academic Search

Subterranean vegetative propagules are important life cycle stages for some species of rooted aquatic plants. Sedi- ments contain numerous compounds resulting from anaero- bic degradation of organic matter, including acetic acid. Tubers of hydrilla (Hydrilla verticillata (L.f.) Royle) and sago pondweed ( Potamogeton pectinatus L. ) were exposed to a range of acetic acid concentrations (0, 17.4, 87, 174, 348,

DAVID F. SPENCER; G. G. KSANDER

336

Effect of Acetic, Lactic and other Organic Acids on the Formation of Artificial Carious Lesions  

Microsoft Academic Search

Artificial carious lesions were produced in human enamel using a diphosphonate\\/organíc acid system over periods up to 30 days, and progress assessed by depth measurement. Acids studied were lactic, acetic, propionic, isobutyric, succinic, tartaric, hydrochloric and hydrofluoric. The rate of lesion progress was found to be a function of calculated unionized acid concentration, and acid dissociation constant. Acetic acid made

J. D. B. Featherstone; B. E. Rodgers

1981-01-01

337

Uptake kinetics of acetic acid and acetone on ice surfaces at 190 - 223 K  

Microsoft Academic Search

Heterogeneous reactions of oxygenated organics may influence the oxidation capacity of the atmosphere with a direct impact on the tropospheric ozone budget. Direct trace gas measurements in the upper troposphere have revealed a high mixing ratio acetic acid (up to 1.9 ppb) and acetone (up to 3 ppb). In the present study we have examined the heterogeneous interactions of acetic

A. Terziyski; P. Behr; U. Scharfenort; K. Demiral; R. Zellner

2003-01-01

338

Acidbase equilibrium of ?-adrenoceptor blocking agents in acetic acid medium and methods for their titration  

Microsoft Academic Search

The overall dissociation constants and the formation constants of the perchlorate salts, in anhydrous acetic acid, of a series of ß-adrenoceptor blocking agents have been determined. On the basis of these values simple potentiometric and visual titration methods for the assay of ß-adrenoceptor blocking drugs in acetic acid are described.

José Barbosa; Maria Eleno Torrero

1991-01-01

339

Comparison of acetate utilization among strains of an aceticlastic methanogen, Methanothrix soehngenii  

Microsoft Academic Search

Methane fermentation has been widely used as a waste-water treatment system because of the low consumption of energy, low level of sludge production, and recovery of methane as a source of energy. In this system, acetate is the precursor for about 70% of the methane produced during the anaerobic digestion of organic compounds, and the decarboxylation of acetate is considered

Sadami Ohtsubo; Kazuhiro Demizu; Shuhei Kohno; Isao Miura; Takahira Ogawa; Hideo Fukuda

1992-01-01

340

Microbial acetate conversion to methane: kinetics, yields and pathways in a two-step digestion process  

Microsoft Academic Search

Organic waste is converted in a two-stage process to methane and carbon dioxide by mixed cultures of microorganisms. Acetate, a product of acidogenic and acetogenic bacteria and the main substrate for methanogenic bacteria, is an important intermediate of the anaerobic degradation process, which results in the generation of methane. It was shown by labelling experiments using (U-14C) acetate that as

Hans Weber; Klaus D. Kulbe; Horst Chmiel; Walter Trösch

1984-01-01

341

Molecular biology and genetics of the acetate-utilizing methanogenic bacteria  

Microsoft Academic Search

Acetate conversion to methane and C0â by the methanogenic archaebacteria is a primary rate limiting step in anaerobic biodegradative processes in nature. However, the genetic study of these organisms has not been experimentally tractable due to the inability to grow and plate the organisms as single cells, and to extract high molecular weight DNA and RNA without shearing. The acetate-utilizing

Gunsalus

1991-01-01

342

[Conversion of acetic acid to methane by thermophiles]. Annual progress report  

Microsoft Academic Search

Acetate is the precursor of approximately two-thirds of the methane produced by anaerobic bioreactors and many other methanogenic habitats. Besides their intrinsic interest, thermophilic acetotrophic methanogenic cultures usually grow at least twice as fast as their mesophilic counterparts, making them more amenable to study. In recent years, attention has been mainly focused on the thermophilic acetate utilizing methanogen Methanothrix strain

Zinder

1994-01-01

343

The possible role of acetate in exercise hyperemia in dog skeletal muscle  

Microsoft Academic Search

The possible role of acetate in the genesis of exercise hyperemia was studied in five series of dogs. Intraarterial infusion of an isomotic solution of sodium acetate at 0.76 ml\\/min in the dog forelimb decreased the resistance to flow through skeletal muscle by 48%, primarily by decreasing resistance to flow through small vessels. Skin lymph flow and lymph protein concentration

Robert P. Steffen; Jack E. McKenzie; Francis J. Haddy

1982-01-01

344

Zymomonas with improved ethanol production in medium containing concentrated sugars and acetate  

DOEpatents

Through screening of a Zymomonas mutant library the himA gene was found to be involved in the inhibitory effect of acetate on Zymomonas performance. Xylose-utilizing Zymomonas further engineered to reduce activity of the himA gene were found to have increased ethanol production in comparison to a parental strain, when cultured in medium comprising xylose and acetate.

Caimi, Perry G. (Kennett Square, PA); Chou, Yat-Chen (Lakewood, CO); Franden, Mary Ann (Centennial, CO); Knoke, Kyle (Newark, DE); Tao, Luan (Havertown, PA); Viitanen, Paul V. (West Chester, PA); Zhang, Min (Lakewood, CO); Zhang, Yuying (New Hope, PA)

2010-09-28

345

Preparation of biomaterials on the basis of a water-soluble cellulose acetate  

NASA Astrophysics Data System (ADS)

Biomaterials were obtained on the basis of water-soluble cellulose acetate and diterpenoids group of plants Lagohulusa intoxicating having hemostatic properties. It is established that these biomaterials on the basis of water-soluble cellulose acetate and lagohilina (or lagohirzina) had increased hemostatic activity and reduce parenchymal hemorrhage 5-6 times compared to control.

Akmalova, G. Yu.; Gulyamova, N. S.; Zainutdinov, U. N.; Rakhmanberdiev, G. R.; Negmatova, K. S.; Negmatova, M. I.

2012-07-01

346

DOI: 10.1002/chem.200700579 Selective Catalytic Oxidation of Ethanol to Acetic Acid on Dispersed  

E-print Network

, easily separated from organic reactants and products, and gas-phase process- es that avoid solid% ethanol conversion) were much higher than in previous re- ports. The presence of TiO2 during syn- thesis that are converted to acetic acid. Water increases acetic acid selec- tivity by inhibiting acetaldehyde syn- thesis

Iglesia, Enrique

347

Effect of Acetic Acid on the Oxidation of Ascorbic Acid in Fruits and Vegetables  

Microsoft Academic Search

IT has been established by earlier investigators that acetic acid has a destructive effect on the ascorbic acid in raw cabbage. This effect is somewhat surprising, since the lower the pH in the medium, the more stable is the ascorbic acid and, therefore, one would expect the acetic acid to have a preservative effect on the ascorbic acid in cabbage.

F. Alm

1952-01-01

348

The Vinyl Acetate Content of Packaging Film: A Quantitative Infrared Experiment.  

ERIC Educational Resources Information Center

Presents an experiment used in laboratory technician training courses to illustrate the quantitative use of infrared spectroscopy which is based on industrial and laboratory procedures for the determination of vinyl acetate levels in ethylene vinyl acetate packaging films. Includes three approaches to allow for varying path lengths (film…

Allpress, K. N.; And Others

1981-01-01

349

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

PubMed

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

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

2011-06-01

350

Chiral phosphoric acid directed regioselective acetalization of carbohydrate-derived 1,2-diols.  

PubMed

In control: A chiral phosphoric acid catalyst significantly enhances or completely overrides the inherent regioselective acetalization profiles exhibited by monosaccharide-derived 1,2-diol substrates. This study represents the first example of chiral-catalyst-directed regio- and enantioselective intermolecular acetalizations, which are complementary to existing methods for substrate-controlled functionalization of polyols. PMID:24123751

Mensah, Enoch; Camasso, Nicole; Kaplan, Will; Nagorny, Pavel

2013-12-01

351

Vapor-phase esterification of acetic acid with ethanol catalyzed by a macroporous sulfonated styrene-divinylbenzene (20%) resin  

SciTech Connect

The kinetics of the vapor-phase (85-120/sup 0/C) esterification of acetic acid with ethyl alcohol, at atmospheric pressure, catalyzed by a macroporous sulfonated styrene-divinylbenzene (DVB;20%) resin, has been studied. A simple first-order model (r = kp/sub 1/) fits experimental kinetic data properly for a constant reactants ratio. Discussion by means of L-H-H-W models shows that the rate-controlling step is the surface reaction with a single-site mechanism. The apparent activation energy is 4000 cal/mol.

Gimenez, J.; Costa, J.; Cervera, S.

1987-02-01

352

Complexation of chitosan with acetic acid according to Fourier transform Raman spectroscopy data  

NASA Astrophysics Data System (ADS)

The results of the interaction between the protonated chitosan (CHI) macromolecule and the acetate ion in dilute acetic acid solutions were studied by Fourier transform Raman spectroscopy and quantum-chemical modeling. The complexation of CHI with the acetate ion showed itself as the 934 cm-1 band in the Raman spectrum, which suggests the formation of [CHI+ · CH3COO-] type ion pairs. It was concluded that a comparative analysis of the integrated intensities of the Raman bands in the range 880-940 cm-1 makes it possible to judge about the relative content of hydrated acetate ions, CHI macromolecules of the [CHI+ · CH3COO-] complex, and acetic acid molecules not involved in CHI protonation.

Mikhailov, G. P.; Tuchkov, S. V.; Lazarev, V. V.; Kulish, E. I.

2014-06-01

353

The use of polyphenolic extract, purified hydroxytyrosol and 3,4-dihydroxyphenyl acetic acid from olive mill wastewater for the stabilization of refined oils: a potential alternative to synthetic antioxidants  

Microsoft Academic Search

Ethyl acetate extracts of olive mill waste water (OMWW) were prepared, under in optimal conditions, using a continuous counter-current extraction unit. The antiradical and antioxidant activities of the OMWW extract as well as pure phenolic compounds identified in this extract were evaluated. Results showed that pure hydroxytyrosol and 3,4-dihydroxyphenyl acetic acid had the highest radical-scavenging effects on 1,1-diphenyl-2-picrylhydrazyl radical and

Ines Fki; Noureddine Allouche; Sami Sayadi

2005-01-01

354

Isolation, characterization and optimization of indigenous acetic acid bacteria and evaluation of their preservation methods  

PubMed Central

Background and Objectives Acetic acid bacteria (AAB) are useful in industrial production of vinegar. The present study aims at isolation and identification of acetic acid bacteria with characterization, optimization, and evaluation of their acetic acid productivity. Materials and Methods Samples from various fruits were screened for presence of acetic acid bacteria on glucose, yeast extract, calcium carbonate (GYC) medium. Carr medium supplemented with bromocresol green was used for distinguishing Acetobacter from Gluconobacter. The isolates were cultured in basal medium to find the highest acetic acid producer. Biochemical tests followed by 16S rRNA and restriction analyses were employed for identification of the isolate and phylogenic tree was constructed. Bacterial growth and acid production conditions were optimized based on optimal inoculum size, pH, temperature, agitation, aeration and medium composition. Results Thirty-seven acetic acid bacteria from acetobacter and gluconobacter members were isolated. Acetic acid productivity yielded 4 isolates that produced higher amounts of acid. The highest producer of acid (10.03%) was selected for identification. The sequencing and restriction analyses of 16S rRNA revealed a divergent strain of Acetobacter pasteurianus (Gene bank accession number#GU059865). The optimum condition for acid production was a medium composed of 2% glucose, 2% yeast extract, 3% ethanol and 3% acid acetic at inoculum size of 4% at 3L/Min aeration level in the production medium. The isolate was best preserved in GYC medium at 12°C for more than a month. Longer preservation was possible at ?70°C. Conclusion The results are suggestive of isolation of an indigenous acetic acid bacteria. Pilot plan is suggested to study applicability of the isolated strain in acetic acid production. PMID:22347549

Sharafi, SM; Rasooli, I; Beheshti-Maal, K

2010-01-01

355

C-13 Stable Isotope Probing of Biostimulation Experiments to Identify Acetate Utilizers  

NASA Astrophysics Data System (ADS)

In order to determine which microorganisms take up acetate during biostimulation and how the uptake of acetate by specific organisms, especially Geobacter species, changes over time, a 120-day column biostimulation experiment was performed. A total of eight columns were loaded with Rifle sediments and operated under continuous flow conditions using Rifle groundwater, amended with 3 mM C-12 acetate. At regular time intervals, C-12 acetate flow into a specific column was switched to C-13 acetate. That column was then operated under C-13 acetate amendment for 36 hours before it was sacrificed for detailed geochemical and microbiological analyses. Column operation started under iron reduction (based on the measured Fe(II) in the column effluent), while sulfate reduction (based on removal of sulfate between influent and outflow), was noted at about 25 days of operation. The microbial characterization consisted of phospholipid fatty acid analysis (PLFA) and stable isotope probing (SIP). All microbial characterization was done to differentiate between the C-12 and C-13 incorporation into the biomass. Results showed that there was a differentiation between the community that was taking up acetate actively throughout the 120 days of operation and the overall microbial community. Of interest was that the fraction of Geobacter population remained fairly constant throughout the duration of the experiment, as well as its acetate uptake. Results also showed that of the acetate incorporated into the overall biomass, about 40% was incorporated into Geobacter biomass. These results are key for the proper numerical simulations of biostimulation via acetate amendment and the biostimulation of Geobacter.

Jaffe, P. R.; Tan, H.; Kerkhof, L.; McGuinness, L.; Peacock, A.; Long, P. E.

2011-12-01

356

Microbial dynamics in acetate-enriched ballast water at different temperatures.  

PubMed

The spread of invasive species through ships' ballast water is considered as a major ecological threat to the world's oceans. For that reason, the International Maritime Organization (IMO) has set performance standards for ballast water discharge. Ballast water treatment systems have been developed that employ either UV-radiation or 'active substances' to reduce the concentration of living cells to below the IMOs standards. One such active substance is a chemical mixture known as Peraclean(®) Ocean. The residual of Peraclean(®) Ocean is acetate that might be present at high concentrations in discharged ballast water. In cold coastal waters the breakdown of acetate might be slow, causing a buildup of acetate concentrations in the water if regularly discharged by ships. To study the potential environmental impact, microbial dynamics and acetate degradation were measured in discharge water from a Peraclean(®) Ocean treatment system in illuminated microcosms. In addition, microbial dynamics and acetate degradation were studied at -1, 4, 10, 15 and 25°C in dark microcosms that simulated enclosed ballast water tanks. Acetate breakdown indeed occurred faster at higher temperatures. At 25°C the highest bacteria growth, fastest nutrient and oxygen consumption and highest DOC reduction occurred. On the other hand, at -1°C bacterial growth was strongly delayed, only starting to increase after 12 days. Furthermore, at 25°C the acetate pool was not depleted, probably due to nutrient and oxygen limitation. This means that not all acetate will be broken down in ballast water tanks, even during long voyages in warm waters. In addition, at low temperatures acetate breakdown in ballast water tanks and in discharged water will be extremely slow. Therefore, regular discharge of acetate enriched ballast water in harbors and bays may cause eutrophication and changes in the microbial community, especially in colder regions. PMID:23871568

Stehouwer, Peter Paul; van Slooten, Cees; Peperzak, Louis

2013-10-01

357

Evaluation of the morphological changes of gastric mucosa induced by a low concentration of acetic acid using a rat model.  

PubMed

Oral ingestion of concentrated acetic acid causes corrosive injury of the gastrointestinal tract. To assess the effects of a low concentration of acetic acid on gastric mucosa, we examined the gastric mucosal changes in rats at 1 and 3 days after the injection of 5% or 25% acetic acid into the gastric lumen. The area of the gastric ulcerative lesions in the 25% acetic acid group was significantly larger than that in the 5% acetic acid group. The lesion area was reduced significantly at 3 days after injection in the 5% acetic acid group, whereas no significant difference in lesion area was observed at 1 and 3 days in the 25% acetic acid group. Histologically, corrosive necrosis was limited to the mucosal layer in the 5% acetic acid group, whereas necrosis extended throughout the gastric wall in the 25% acetic acid group. At 3 days post-injection, the 25% acetic acid group showed widespread persistent inflammation, whereas the 5% acetic acid group showed widespread appearance of fibroblasts indicative of a healing process. These results indicate that a low concentration of acetic acid damages the gastric mucosa and that the degree of mucosal damage depends on the concentration of acetic acid. PMID:24485432

Nakao, Ken-ichiro; Ro, Ayako; Kibayashi, Kazuhiko

2014-02-01

358

Transport properties of polyaniline-cellulose-acetate blends  

NASA Astrophysics Data System (ADS)

Transport properties of polyaniline (PANI)-cellulose acetate (CA) conducting blends have been investigated at various length scales and temperatures. We report on the results of dc and ac conductivity measurements, magnetoresistance and electron-spin resonance (ESR) performed on composite films with PANI weight fraction p ranging from the percolation threshold-pc~=0.1%-to a few percent. Three different PANI doping agents have been tested, namely, camphor sulfonic acid (CSA), di(i-octyl phosphate) (DiOP) and phenyl phosphonic acid (PPA). The percolative behavior of ?dc resembles that of published results on PANI/PMMA blends. The onset frequency ?? of the dispersion in ?ac appears to follow the scaling law: ??~?zdc with z~=1. The temperature dependence is of the form of ln?(T)~-(T0/T)? the exponent decreasing from 0.75 to 0.5 with increasing p. The microscopic metallic character of transport is found in ESR and microwave measurements. Spin-dependent conductivity is inferred from the (B/T)2 universal behavior of magnetoresistance. Those results are discussed in conjunction with the ongoing debate on the nature of disorder in conducting polymers-homogeneous versus heterogeneous.

Planès, Jérôme; Wolter, Andreas; Cheguettine, Yasmina; Pro?, Adam; Genoud, Françoise; Nechtschein, Maxime

1998-09-01

359

Cellulose acetate electrospun fiber mats for controlled release of silymarin.  

PubMed

In this research, the silymarin-loaded electrospun cellulose acetate (CA) fibers were prepared which containing silymarin in various amounts (i.e., 2.5-20 wt.% based on the weight of CA powder). Incorporation of silymarin in the neat CA solution did not affect the morphology of the resulting fibers, as both the neat and the silymarin-loaded CA fibers were smooth. The average diameters of silymarin-loaded CA fiber ranged between 550-900 nm. No presence of the silymarin aggregates of any kind was observed on the surfaces of these fibers, suggesting that the silymarin was encapsulated well within the fibers. These results were confirmed by lowering the glass transition temperature and the melting temperature of the silymarin-loaded electrospun CA fibers which is determined by DSC technique. The release characteristic of silymarin from the silymarin-loaded CA fiber mats was investigated by the total immersion in the solution of 1/1 phosphate buffer/methanol medium pH 7.4 at 37 degrees C. The silymarin release from the silymarin-loaded electrospun CA fiber mat is monotonously increased to reach the maximum value at 480 min. The maximum amount of silymarin released from these materials increases with the increasing of initial silymarin loading in the spinning CA solutions. Since no aggregation of silymarin was found on the surface of the silymarin-loaded fibers, the release of the silymarin from fiber mats was mainly by the diffusion. PMID:22524059

Phiriyawirut, Manisara; Phaechamud, Thawatchai

2012-01-01

360

Plasmacatalytic removal of lead acetate assisted by precipitation.  

PubMed

The Gliding Arc Discharge (GAD) is an efficient non-thermal plasma technique able to degrade organic compounds dispersed in water at atmospheric pressure. The degradation of the organometallic lead acetate (PbAc) in aqueous solution was performed by two distinct plasmageneous processes: GAD and GAD/TiO2. The global oxidation of the organic matter was followed by Chemical Oxygen Demand (COD) and the mineralization was determined by the Total Organic Carbon (TOC). The Pb(2+) ions released during the degradation process were measured by Atomic Absorption Spectroscopy (AAS). For 2h of GAD treatment, the degradation rate of PbAc (10mM) reached 83% and for the same duration of GAD/TiO2 process ([TiO2]=1gL(-1)), it reached 93%. The release of Pb(2+) ions in the solution was respectively of 95% and 57% for GAD and GAD/TiO2 processes. The released Pb(2+) ions were removed by precipitation process in a basic medium at pH=11.1. A reaction mechanism was proposed to explain the PbAc molecule degradation and the Pb(2+) elimination. PMID:24462087

Haddou, Nabila; Ghezzar, Mouffok Redouane; Abdelmalek, Fatiha; Ognier, Stéphanie; Martel, Marc; Addou, Ahmed

2014-07-01

361

The synthetic progestin megestrol acetate adversely affects zebrafish reproduction.  

PubMed

Synthetic progestins contaminate the aquatic ecosystem, and may cause adverse health effects on aquatic organisms. Megestrol acetate (MTA) is present in the aquatic environment, but its possible effects on fish reproduction are unknown. In the present study, we investigated the endocrine disruption and impact of MTA on fish reproduction. After a pre-exposure period of 14 days, reproductively mature zebrafish (Danio rerio) (F0) were exposed to MTA at environmental concentrations (33, 100, 333, and 666 ng/L) for 21 days. Egg production was decreased in F0 fish exposed to MTA, with a significant decrease at 666 ng/L. The exposure significantly decreased the circulating concentrations of estradiol (E2) and testosterone (T) in female fish or 11-keto testosterone (11-KT) in male fish. MTA exposure significantly downregulated the transcription of certain genes along the hypothalamic-pituitary-gonadal (HPG) axis. MTA did not affect early embryonic development or hatching success in the F1 generation. The present study showed that MTA is a potent endocrine disruptor in fish, and short-term exposure to MTA could significantly affect reproduction in fish and negatively impact the fish population. PMID:24647012

Han, Jian; Wang, Qiangwei; Wang, Xianfeng; Li, Yonggang; Wen, Sheng; Liu, Shan; Ying, Guangguo; Guo, Yongyong; Zhou, Bingsheng

2014-05-01

362

Bone density in long term users of depot medroxyprogesterone acetate.  

PubMed

The effects on bone density of long-term depot medroxyprogesterone acetate (DMPA) use were investigated in a cross-sectional study of 185 clients 17-52 years of age at family planning clinics in Portsmouth and Manchester, England, who had been receiving contraceptive injections for 1-16 years (median, 5 years). Dual energy x-ray measurements of bone density of the femoral neck and lumbar spine, as well as venous blood samples, were taken prior to the women's next DMPA injection (1994-96). 153 women had serum estradiol levels under 150 pmol/l--the value considered adequate to maintain bone density. The mean bone density of the lumbar spine compared with the population mean for women 20-59 years old yielded a Z score of minus 0.332 (95% confidence interval, -0.510 to -0.154; p 0.001). There was a weak, nonsignificant correlation between lumbar spine Z score and years of DMPA use. Mean density of the femoral neck did not differ significantly from the normal population mean. There was no significant correlation between serum estradiol level and either bone density score. Overall, these findings provide no evidence that DMPA-induced amenorrhea places women at significant risk of further bone loss or that supplemental estrogen is required. PMID:9692421

Gbolade, B; Ellis, S; Murby, B; Randall, S; Kirkman, R

1998-07-01

363

Hydrogen bonding in hydrates with one acetic acid molecule.  

PubMed

Hydrogen bonding (H-bond) interaction significantly influences the separation of acetic acid (HAc) from the HAc/H(2)O mixtures, especially the dilute solution, in distillation processes. It has been examined from the HAc mono-, di-, tri-, and tetrahydrates by analyzing the structures, binding energies, and infrared vibrational frequencies from quantum chemical calculations. For the first coordinate shell the 6-membered head-on ring is surely the most favorable structure because it has (1) the most favorable H-bonding parameters, (2) almost the largest binding energy per H-bond, (3) the biggest wavenumber shifts, and (4) the highest ring distribution (the AIMD simulations). Moreover, the comparison of the calculations with the experiments (the X-ray scattering data and IR frequencies) suggests that the possible structures in dilute aqueous solution are those involving two or more coordinate shells. The H-bonding in these water-surrounded HAc hydrates are the origin of the low-efficiency problem of isolating HAc from the dilute HAc/H(2)O mixtures. It is apparently a tougher work to break the H-bonds among HAc and the surrounded H(2)O molecules with respect to the case of more concentrated solutions, where the dominant structures are HAc or H(2)O aggregates. PMID:20853886

Pu, Liang; Sun, Yueming; Zhang, Zhibing

2010-10-14

364

[Abiraterone acetate(ZYTIGA®)-development and literature review].  

PubMed

Abiraterone acetate(AA)has been approved in more than 80 countries for the treatment of patients with metastatic castration-resistant prostate cancer(mCRPC). In July 2013, a marketing approval application for AA was submitted to the Japanese Ministry of Health, Labour, and Welfare. AA is a selective inhibitor of CYP17A1, a crucial enzyme for androgen biosynthesis. AA exerts its anti-tumor activity by directly inhibiting androgen production at all three sources, i. e., the testes, adrenal glands, and tumor itself. Data from international phase III studies and phase I and II studies in Japan have indicated that AA improves the overall survival and quality of life(QoL)of patients with mCRPC. Herein, we have summarized the development of AA and the results of important international and local clinical trials in Japan. In addition, the effect of food on AA bioavailability, concomitant steroid use, and liver function test abnormalities have been discussed regarding the appropriate use of AA. PMID:25131865

Nishimura, Yukiko; Mukai, Harumi; Suzukawa, Kazumi; Oyama, Ryo

2014-07-01

365

Committee Opinion No. 602: Depot medroxyprogesterone acetate and bone effects.  

PubMed

Depot medroxyprogesterone acetate (DMPA) is a highly effective injectable contraceptive that affords privacy and has a convenient dose schedule of four times per year, making it appealing to many users, especially adolescents. Although the use of DMPA is associated with loss of bone mineral density (BMD), current longitudinal and cross-sectional evidence suggests that recovery of BMD occurs after discontinuation of DMPA. No high-quality data answer the important clinical question of whether DMPA affects fracture risk in adolescents or adults later in life. The effect of DMPA on BMD and potential fracture risk should not prevent practitioners from prescribing DMPA or continuing use beyond 2 years. The potential health risks associated with the bone effects of DMPA must be balanced against a woman's likelihood of pregnancy using other methods or no method, and the known negative health and social consequences associated with unintended pregnancy, particularly among adolescents. Health care providers should inform women and adolescents considering initiating DMPA or continuing to use the method about the benefits and the risks of DMPA and should discuss the U.S. Food and Drug Administration "black box" warning and use clinical judgment to assess appropriateness of use. PMID:24848921

2014-06-01

366

Cyproterone acetate in the therapy of prostate carcinoma.  

PubMed

Prostatic carcinoma is one of the most commonly neoplasm in men, with the strongest incidence around the age of 70 years. In consideration of the high hormonodependence of prostatic neoplasm the reduction of testosterone levels represents the choice of treatment for the patients with metastatic disease, and has an application also in the treatment of patients with a more limited disease, but not elegible to local treatment with a curative aim. The circulating testosterone can be maintained to the lowest levels by the use of drugs that can obtain, with different mechanism of action, a "medical castration". Cyproterone acetate (CPA) is a steroideal antiandrogen which has affinity with progesteron and with glucocorticoidal receptors. It centrally inhibits the release of lutehinizing hormon blocking in this way the secretion of testosterone of testicular origin. Besides, it inhibits the action of the androgens of surrenalic and testicular origin to the cellular level through a competitive direct interaction with the cellular receptors. This review illustrates the main evidences of efficacy and safety of CPA in the treatment of prostatic carcinoma. PMID:16372511

Torri, Valter; Floriani, Irene

2005-06-01

367

Successful Pregnancy after Treatment with Ulipristal Acetate for Uterine Fibroids  

PubMed Central

This case report presents a clinical pregnancy after ulipristal acetate (UA) to decrease uterine fibroid size. A 37-year-old patient, gravida 1, abortus 1, with uterine fibroids was treated with 5?mg of UA daily for 13 weeks starting eight months after a multiple laparotomic myomectomy. Fibroid shrinkage and restoration of the morphology of endometrial cavity were evaluated in order to allow a subsequent pregnancy. A decrease of the uterine fibroids and a normal morphology of the endometrial cavity were noted by transvaginal ultrasound after treatment. An endometrial biopsy excluded histologic endometrial changes. Three months after the end of UA the patient reported amenorrhea for 5 weeks and a clinical pregnancy was confirmed with transvaginal ultrasound. She underwent a subsequent uneventful pregnancy. Thus, the spontaneous pregnancy after UA to reduce fibroid size may support the potential clinical utility of this selective progesterone receptor modulator in the management of women with pregnancy desire and uterine fibroids after a prior myomectomy. Patients who refuse a new surgical procedure and/or those who are going to undergo assisted reproductive techniques would benefit from UA. It effectively shrinks fibroids, avoids risks of a new surgical procedure, and allows an immediate attempt at conception after the end of treatment. PMID:25143845

Monleon, Javier; Galliano, Daniela; Pellicer, Antonio

2014-01-01

368

Protective effects of incensole acetate on cerebral ischemic injury.  

PubMed

The resin of Boswellia species is a major anti-inflammatory agent that has been used for centuries to treat various conditions including injuries and inflammatory conditions. Incensole acetate (IA), a major constituent of this resin, has been shown to inhibit NF-?B activation and concomitant inflammation, as well as the neurological deficit following head trauma. Here, we show that IA protects against ischemic neuronal damage and reperfusion injury in mice, attenuating the inflammatory nature of ischemic damage. IA given post-ischemia, reduced infarct volumes and improved neurological activities in the mouse model of ischemic injury in a dose dependent fashion. The protection from damage was accompanied by inhibition of TNF-?, IL-1? and TGF-? expression, as well as NF-?B activation following injury. In addition, IA is shown to have a therapeutic window of treatment up to 6h after ischemic injury. Finally, the protective effects of IA were partially mediated by TRPV3 channels as determined by the TRPV3 deficient mice and channel blocker studies. This study suggests that the anti-inflammatory and neuroprotective activities of IA may serve as a novel therapeutic treatment for ischemic and reperfusion injury, and as a tool in the ongoing research of mechanisms for neurological damage. PMID:22284622

Moussaieff, Arieh; Yu, Jin; Zhu, Hong; Gattoni-Celli, Sebastiano; Shohami, Esther; Kindy, Mark S

2012-03-14

369

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

SciTech Connect

Half of U.S. acetic acid production is used in manufacturing vinyl acetate monomer (VAM) and is economical only in very large production plants. Nearly 80% of the VAM is produced by methanol carbonylation, which requires high temperatures and exotic construction materials and is energy intensive. Fermentation-derived acetic acid production allows for small-scale production at low temperatures, significantly reducing the energy requirement of the process. The goal of the project is to develop a scaleable production and separation process for fermentation-derived acetic acid. Synthesis gas (syngas) will be fermented to acetic acid, and the fermentation broth will be continuously neutralized with ammonia. The acetic acid product will be recovered from the ammonium acid broth using vapor-based membrane separation technology. The process is summarized in Figure 1. The two technical challenges to success are selecting and developing (1) microbial strains that efficiently ferment syngas to acetic acid in high salt environments and (2) membranes that efficiently separate ammonia from the acetic acid/water mixture and are stable at high enough temperature to facilitate high thermal cracking of the ammonium acetate salt. Fermentation - Microbial strains were procured from a variety of public culture collections (Table 1). Strains were incubated and grown in the presence of the ammonium acetate product and the fastest growing cultures were selected and incubated at higher product concentrations. An example of the performance of a selected culture is shown in Figure 2. Separations - Several membranes were considered. Testing was performed on a new product line produced by Sulzer Chemtech (Germany). These are tubular ceramic membranes with weak acid functionality (see Figure 3). The following results were observed: (1) The membranes were relatively fragile in a laboratory setting; (2) Thermally stable {at} 130 C in hot organic acids; (3) Acetic acid rejection > 99%; and (4) Moderate ammonia flux. The advantages of producing acetic acid by fermentation include its appropriateness for small-scale production, lower cost feedstocks, low energy membrane-based purification, and lower temperature and pressure requirements. Potential energy savings of using fermentation are estimated to be approximately 14 trillion Btu by 2020 from a reduction in natural gas use. Decreased transportation needs with regional plants will eliminate approximately 200 million gallons of diesel consumption, for combined savings of 45 trillion Btu. If the fermentation process captures new acetic acid production, savings could include an additional 5 trillion Btu from production and 7 trillion Btu from transportation energy.

Snyder, S. W.; Energy Systems

2010-02-08

370

Extraction and sorption of acetic acid at pH above pK{sub a} to form calcium magnesium acetate  

SciTech Connect

The use of rock salt for deicing roads has many negative effects on automobiles, highway systems, and the environment. Calcium magnesium acetate, hence-forth denoted CMA, has been identified as a more desirable, environmentally benign solid deicer for high-ways, airport runaways, and similar applications. CMA is also of interest as an additive for scavenging sulfur in combustion processes so as to reduce emissions of sulfur oxides and as a catalyst for coal gasification. Different extractants (trioctylphosphine oxide and secondary, tertiary, and quaternary amines) and solid sorbents (tertiary and quaternary amines) were investigated as agents for recovery of acetic acid as part of a process for production of CMA from fermentation acetic acid. The pH and temperature dependencies for uptake of acetic acid by these extractants and sorbents were measured, along with the degrees of regeneration by aqueous suspensions of slaked dolomitic lime. These results enable identification of agents having optimal basicity. Among the extractants, the secondary amine Amberlite LA-2 gave the best combined performance for extraction and regeneration. Among the sorbents, a tertiary amine, Amberlite IRA-35, gave the best performance. Trioctylphosphine oxide does not maintain capacity in the pH range (about 6) most attractive for acetic acid fermentation. Slurred crushed dolomite is not sufficiently basic to accomplish regeneration.

Reisinger, H.; King, C.J. [Lawrence Berkeley Lab., CA (United States)

1995-03-01

371

Thermodynamic modeling of neptunium(V)-acetate complexation in concentrated NaCl media  

SciTech Connect

The complexation of neptunium(V), Np(V), with the acetate anion, Ac{sup -}, was measured in sodium chloride media to high concentration using an extraction technique. The data were interpreted using the thermodynamic formalism of Pitzer, which is valid to high electrolyte concentrations. A consistent model for the deprotonation constants of acetic acid in NaCl and NaClO{sub 4} media was developed. For the concentrations of acetate expected in a waste repository, only the neutral complex NpO{sub 2}Ac(aq) was important in describing the interactions between the neptunyl ion and acetate. The thermodynamic stability constant log {beta}{sup 0}{sub 101} for the reaction NpO{sub 2}{sup +} + Ac{sup -} {leftrightarrow} NpO{sub 2}Ac was calculated to be 1.46{plus_minus}0.11. This weak complexing behavior between the neptunyl ion and acetate indicates that acetate will not significantly enhance dissolved Np(V) concentrations in ground waters associated with nuclear waste repositories that may contain acetate.

Novak, C.F.; Borkowski, M.; Choppin, G.R.

1995-09-01

372

Can we trust odor databases? Example of t- and n-butyl acetate  

NASA Astrophysics Data System (ADS)

The US EPA has exempted t-butyl acetate from VOC regulations, which increases the likelihood that it may replace other solvents in some settings. This investigation probes its chemosensory properties. In Study 1, subjects ( n = 29) sought to detect the odor of t-butyl acetate and of n-butyl acetate in forced-choice testing of stable concentrations, analytically confirmed. Subjects sniffed from cones with a high enough volumetric flow to insure against dilution by nonodorized air. A subject made hundreds of judgments, enough for a psychometric function for each material. The points of 50% detection above chance ("threshold") occurred at 8 and 2 ppb for t-butyl acetate and n-butyl acetate, respectively. In study 2, subjects ( n = 26) sought to detect vapor with the eye via chemesthesis (sensory irritation) in 10-s exposures. Detection at 50% occurred at 177 and 113 ppm for t-butyl acetate and n-butyl acetate, respectively, more than 10,000 times above that for odor detection. The protocols produced results of uncommon precision compared to those in often-misleading archival databases. The nose exhibits much higher sensitivity than the databases indicate. The collections rarely exhibit accuracy better than ±1000%. Collection of accurate data for a VOC can ironically bring on stricter regulation for just it, a situation that calls for a strategy to improve the database by collection of new data, importation of better data, and development of quantitative structure-activity modeling.

Cain, William S.; Schmidt, Roland

373

Combustion process and nitrogen oxides emission of Shenmu coal added with sodium acetate  

SciTech Connect

Shenmu bituminous coal with 4% sodium acetate added was used to investigate the characteristics of combustion and nitrogen oxide (NOx) release in a fixed bed reactor heated by a tube furnace. The composition of the flue gas was analyzed to investigate the effects of sodium acetate on the combustion process and NOx emission. The experiments were carried out in a partial reductive atmosphere and a strong oxidative atmosphere. The O{sub 2} valley value in the partial reductive atmosphere was reduced by the added sodium acetate. Sodium acetate accelerated the combustion and shortened the combustion process. The experimental results showed that the emissions of NO, NO{sub 2}, and N{sub 2}O were affected by the reacting atmosphere and the combustion temperature. In the strong oxidative atmosphere, sodium acetate resulted in a slight NOx reduction. In the partial reductive atmosphere, sodium acetate reduced both the peak value of NO concentration and the total NO emission significantly. An over 30% NOx reduction efficiency was achieved at 900{sup o}C in the partial reductive atmosphere, which decreased with the increase in temperature. Sodium acetate was decomposed into hydrocarbon radicals and sodium hydroxide, which can both reduce NOx emissions due to their special reactions with the nitrogen component. 17 refs., 11 figs., 2 tabs.

Yang Weijuan; Zhou Junhu; Liu Maosheng; Zhou Zhijun; Liu Jianzhong; Cen Kefa [Zhejiang University, Hangzhou (China). State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering

2007-09-15

374

Point mutation of H3/H4 histones affects acetic acid tolerance in Saccharomyces cerevisiae.  

PubMed

The molecular mechanism of acetic acid tolerance in yeast remains unclear despite of its importance for efficient cellulosic ethanol production. In this study, we examined the effects of histone H3/H4 point mutations on yeast acetic acid tolerance by comprehensively screening a histone H3/H4 mutant library. A total of 24 histone H3/H4 mutants (six acetic acid resistant and 18 sensitive) were identified. Compared to the wild-type strain, the histone acetic acid-resistant mutants exhibited improved ethanol fermentation performance under acetic acid stress. Genome-wide transcriptome analysis revealed that changes in the gene expression in the acetic acid-resistant mutants H3 K37A and H4 K16Q were mainly related to energy production, antioxidative stress. Our results provide novel insights into yeast acetic acid tolerance on the basis of histone, and suggest a novel approach to improve ethanol production by altering the histone H3/H4 sequences. PMID:25093933

Liu, Xiangyong; Zhang, Xiaohua; Zhang, Zhaojie

2014-10-10

375

Choline acetate enhanced the catalytic performance of Candida rogusa lipase in AOT reverse micelles.  

PubMed

Choline acetate is an ionic liquid composed of a kosmotropic anion and a chaotropic cation. According to Hofmeister series, a kosmotropic anion and/or a chaotropic cation could stabilize an enzyme, thereby facilitating the retention of the catalytic activity of the enzyme. In this work, we first report the influence of choline acetate on the activity and stability of lipase in AOT/water/isooctane reverse micelles. The indicator reaction is the lipase-catalyzed hydrolysis of 4-nitrophenyl butyrate. The results show that a low level of choline acetate does not affect the microstructure of the AOT reverse micelles, but the ionic liquid can improve the catalytic efficiency of lipase. Fluorescence spectra show that a high level of choline acetate has an impact on the conformation of lipase, so the activation is mainly due to the influence of choline acetate on the nucleophilicity of water. Infrared spectra demonstrate that choline acetate can form stronger hydrogen bonds with water surrounding lipase, and therefore enhance the nucleophilicity of the water, which makes it easier to attack the acyl enzyme intermediate, thereby increasing the activity of the lipase-catalyzed hydrolysis of the ester. A study on the stability of lipase in AOT reverse micelles indicates that the ionic liquid is able to maintain the activity of lipase to a certain extent. The effect of choline acetate is consistent with that predicted based on Hofmeister series. PMID:23352950

Xue, Luyan; Zhao, Yin; Yu, Lijie; Sun, Yanwen; Yan, Keqian; Li, Ying; Huang, Xirong; Qu, Yinbo

2013-05-01

376

Behavioral responses of Rhagoletis cingulata (Diptera: Tephritidae) to GF-120 insecticidal bait enhanced with ammonium acetate.  

PubMed

GF-120 is a baited formulation of the insecticide spinosad containing 1% ammonium acetate, developed for control of economically important fruit flies. The response of feral cherry fruit flies, Rhagoletis cingulata Loew, to GF-120 augmented with 0, 5, or 10% ammonium acetate was evaluated under orchard conditions. Significantly more flies were observed within 30 cm of bait droplets with 10% ammonium acetate added compared with standard bait or to a water control. These fly visits to GF-120 enhanced with 10 or 5% ammonium acetate lasted an average of 263.2 +/- 85.2 and 337.6 +/- 72.6 s, respectively, compared with 50.3 +/- 36.4 s for standard GF-120. Droplets containing additional ammonium acetate also were contacted by more flies, and more flies fed upon these droplets than on GF-120 or the water control. Furthermore, the duration of feeding on GF-120 bait enhanced with either level of additional ammonium acetate was significantly greater compared with standard GF-120 or water. Feeding events lasted between 61.5 +/- 30.7 and 73.4 +/- 21.0 s on enhanced GF-120 compared with 6.8 +/- 5.7 s on standard GF-120. Collectively, these results indicate that the interaction of feral R. cingulata with GF-120 droplets and the toxicant spinosad can be increased by addition of ammonium acetate. PMID:16937687

Pelz-Stelinski, K S; Gut, L J; Isaacs, R

2006-08-01

377

A paradigm for strain improvement identifies sodium acetate tolerance loci in Zymomonas mobilis and Saccharomyces cerevisiae  

SciTech Connect

The application of systems biology tools holds promise for rational industrial microbial strain development. Here, we characterize a Zymomonas mobilis mutant (AcR) demonstrating sodium acetate tolerance that has potential importance in biofuel development. The genome changes associated with AcR are determined using microarray comparative genome sequencing (CGS) and 454-pyrosequencing. Sanger sequencing analysis is employed to validate genomic differences and to investigate CGS and 454-pyrosequencing limitations. Transcriptomics, genetic data and growth studies indicate that over-expression of the sodium-proton antiporter gene nhaA confers the elevated AcR sodium acetate tolerance phenotype. nhaA over-expression mostly confers enhanced sodium (Na+) tolerance and not acetate (Ac-) tolerance, unless both ions are present in sufficient quantities. NaAc is more inhibitory than potassium and ammonium acetate for Z. mobilis and the combination of elevated Na+ and Ac- ions exerts a synergistic inhibitory effect for strain ZM4. A structural model for the NhaA sodium-proton antiporter is constructed to provide mechanistic insights. We demonstrate that Saccharomyces cerevisiae sodium-proton antiporter genes also contribute to sodium acetate, potassium acetate, and ammonium acetate tolerances. The present combination of classical and systems biology tools is a paradigm for accelerated industrial strain improvement and combines benefits of few a priori assumptions with detailed, rapid, mechanistic studies.

Yang, Shihui [ORNL; Land, Miriam L [ORNL; Klingeman, Dawn Marie [ORNL; Pelletier, Dale A [ORNL; Lu, Tse-Yuan [ORNL; Martin, S L. [North Carolina State University; Guo, Hao-Bo [ORNL; Smith, Jeremy C [ORNL; Brown, Steven D [ORNL

2010-04-01

378

Paradigm for industrial strain improvement identifies sodium acetate tolerance loci in Zymomonas mobilis and Saccharomyces cerevisiae  

SciTech Connect

The application of systems biology tools holds promise for rational industrial microbial strain development. Here, we characterize a Zymomonas mobilis mutant (AcR) demonstrating sodium acetate tolerance that has potential importance in biofuel development. The genome changes associated with AcR are determined using microarray comparative genome sequencing (CGS) and 454-pyrosequencing. Sanger sequencing analysis is employed to validate genomic differences and to investigate CGS and 454-pyrosequencing limitations. Transcriptomics, genetic data and growth studies indicate that over-expression of the sodium-proton antiporter gene nhaA confers the elevated AcR sodium acetate tolerance phenotype. nhaA over-expression mostly confers enhanced sodium (Na{sup +}) tolerance and not acetate (Ac{sup -}) tolerance, unless both ions are present in sufficient quantities. NaAc is more inhibitory than potassium and ammonium acetate for Z. mobilis and the combination of elevated Na{sup +} and Ac{sup -} ions exerts a synergistic inhibitory effect for strain ZM4. A structural model for the NhaA sodium-proton antiporter is constructed to provide mechanistic insights. We demonstrate that Saccharomyces cerevisiae sodium-proton antiporter genes also contribute to sodium acetate, potassium acetate, and ammonium acetate tolerances. The present combination of classical and systems biology tools is a paradigm for accelerated industrial strain improvement and combines benefits of few a priori assumptions with detailed, rapid, mechanistic studies.

Yang, Shihui [ORNL; Land, Miriam L [ORNL; Klingeman, Dawn Marie [ORNL; Pelletier, Dale A [ORNL; Lu, Tse-Yuan [ORNL; Martin, S L. [North Carolina State University; Guo, Hao-Bo [ORNL; Smith, Jeremy C [ORNL; Brown, Steven D [ORNL

2010-01-01

379

Antimicrobial and antioxidant activities of clove essential oil and eugenyl acetate produced by enzymatic esterification.  

PubMed

This work reports the maximization of eugenyl acetate production by esterification of essential oil of clove in a solvent-free system using Novozym 435 as catalyst. The antimicrobial and antioxidant activities of clove essential oil and eugenyl acetate produced were determined. The conditions that maximized eugenyl acetate production were 60 °C, essential oil of clove to acetic anhydride ratio of 1:5, 150 rpm, and 10 wt% of enzyme, with a conversion of 99.87 %. A kinetic study was performed to assess the influence of substrates' molar ratio, enzyme concentration, and temperature on product yield. Results show that an excess of anhydride, enzyme concentration of 5.5 wt%, 50 °C, and essential oil of clove to acetic anhydride ratio of 1:5 afforded nearly a complete conversion after 2 h of reaction. Comparing the antibacterial activity of the essential oil of clove before and after esterification, we observed a decrease in the antimicrobial activity of eugenyl acetate, particularly with regard to minimum inhibitory concentration (MIC). Both eugenyl acetate and clove essential oil were most effective to the gram-negative than gram-positive bacteria group. The results showed a high antioxidant potential for essential oil before and particularly after the esterification reaction thus becoming an option for the formulation of new antioxidant products. PMID:25104002

Vanin, Adriana B; Orlando, Tainara; Piazza, Suelen P; Puton, Bruna M S; Cansian, Rogério L; Oliveira, Debora; Paroul, Natalia

2014-10-01

380

Aspects of the spasmogenic effects of acetate esters on ileal smooth muscle.  

PubMed

Acetate esters, such as aspirin methylester, aspirin and resorcinol monoacetate, induced contractions of guinea-pig ileum. Their actions were selectively antagonized by atropine, but were not affected by ganglion blocking agents, conduction blockers, aging with cooling, anoxia or antihistaminics. On the other hand, N-acetates, such as acetanilide and p-acetaminophenol, and no contractile action on the ileum. These acetate esters thus seemed to have a cholinergic action, and not a direct action on muscle or other known specific receptors for endogenous active substances. The contractions induced by the acetate esters were selectively potentiated by low concentrations of choline, whereas those induced by acetylcholine, nicotine, 5-hydroxytryptamine and histamine were not. However, N-acetates did not induce the contractions even in the presence of choline. Organophosphorus cholinesterase inhibitors, such as diisopropyl fluorophosphate and paraoxon, selectively and irreversibly inhibited the actions of aspirin and N,O-diacetyl-p-aminophenol with or without choline. From these results, it is concluded that the acetate esters with or without choline act through the cholinergic system. However, their actions cannot be explained in terms of known mechanisms, such as acetylcholine release, cholinesterase inhibition or a direct muscarinic action. Therefore, the acetate esters, including phenyl acetate which was supposed to be a releaser of acetylcholine, seem to have a hitherto undescribed type of cholinergic action whose mechanism is unknown. It seems that organophosphate-sensitive esterase(s) in the preparation may be essential for initiation of the actions of the acetate esters with or without choline, but the mechanism of the effect of choline is unknown. PMID:856612

Moritoki, H; Ishida, Y

1977-04-21

381

C11-Acetate and F-18 FDG PET for Men With Prostate Cancer Bone Metastases  

PubMed Central

Purpose of the Report This study tested the feasibility of C11-acetate (acetate) positron emission tomography (PET) imaging to assess response to therapy in men with bone metastatic prostate cancer and compared results for disease detection and response evaluation with F-18 fluorodeoxyglucose (FDG) PET. Materials and Methods Men with ?3 prostate cancer bone metastases identified by Tc-99m methylene diphosphonate (MDP) bone scintigraphy and/or computed tomography were enrolled in a prospective study of serial acetate and FDG PET imaging. Patients were imaged before and 6 to 12 weeks after initial androgen deprivation therapy for new metastatic prostate cancer or first-line chemotherapy with docetaxel for castration-resistant prostate cancer. Qualitative assessment and changes in the tumor:normal uptake ratio were used to assess response by both acetate and FDG PET. In addition, the detection of bone metastases pretherapy was compared for acetate and FDG PET. Results A total of 8 patients with documented bone metastases were imaged, of which 6 were imaged both pre- and post-therapy. Acetate PET detected bone metastases in all 8 patients, whereas FDG PET detected lesions in 6 of the 7 imaged patients. Acetate PET generally detected more metastases with a higher tumor:normal uptake ratio. Qualitative and quantitative assessments of post-treatment response correlated with composite clinical designations of response, stable disease, or progression in 6 of 6 and 5 of 6 by acetate and 4 of 5 and 3 of 5 by FDG PET, respectively. Conclusions In this pilot study, results indicate that acetate PET holds promise for response assessment of prostate cancer bone metastases and is complementary to FDG PET in bone metastasis detection. PMID:21285676

Yu, Evan Y.; Muzi, Mark; Hackenbracht, Joy A.; Rezvani, Brian B.; Link, Jeanne M.; Montgomery, Robert Bruce; Higano, Celestia S.; Eary, Janet F.; Mankoff, David A.

2011-01-01

382

Long-term effectiveness of glatiramer acetate in clinical practice conditions.  

PubMed

Glatiramer acetate currently represents one of the main treatments for relapsing-remitting multiple sclerosis (RRMS). However, the information available about its long-term effect in clinical practice is still limited. Thus, this multicenter retrospective cohort study aimed to assess the long-term effectiveness of glatiramer acetate in this setting. The study population included RRMS patients treated with glatiramer acetate for at least 5years after its marketing authorization and the primary endpoint was long-term clinical effectiveness, defined as absence of disability progression for at least five consecutive years. A total of 149 patients were included into the study, who had received glatiramer acetate for a mean of 6.9±1.4years (5years, n=149; 6years, n=112; 7years, n=63; 8years, n=32; 9years, n=21). More than 85% of patients remained free from disability progression through years 1 to 9 of glatiramer acetate treatment, and 75.2% showed absence of disability progression for at least five consecutive years. Expanded Disability Status Scale (EDSS) scores were maintained, with most patients showing stable/improved EDSS and 92.6% sustaining EDSS <6. Decreased annual relapse rates and increased proportion of relapse-free patients were maintained during the whole glatiramer acetate treatment compared to the year prior to its authorization (p<0.001). The number of gadolinium-enhanced T1-weighted lesions also decreased from pre-glatiramer-acetate assessment to last follow-up whilst on glatiramer acetate (p<0.05). In conclusion, administration of glatiramer acetate shows long-term clinical effectiveness for RRMS treatment; its effect under clinical practice conditions slowed disability progression and reduced relapse occurrence for up to 9years. PMID:25257663

Arnal-García, Carmen; Amigo-Jorrin, Maria Del Campo; López-Real, Ana Maria; Lema-Devesa, Carme; Llopis, Noemi; Sanchez-de la Rosa, R

2014-12-01

383

Acetate Availability and Utilization Supports the Growth of Mutant Sub-Populations on Aging Bacterial Colonies  

PubMed Central

When bacterial colonies age most cells enter a stationary phase, but sub-populations of mutant bacteria can continue to grow and accumulate. These sub-populations include bacteria with mutations in rpoB (RNA polymerase ?-subunit) or rpoS (RNA polymerase stress-response sigma factor). Here we have identified acetate as a nutrient present in the aging colonies that is utilized by these mutant subpopulations to support their continued growth. Proteome analysis of aging colonies showed that several proteins involved in acetate conversion and utilization were upregulated during aging. Acetate is known to be excreted during the exponential growth phase but can be imported later during the transition to stationary phase and converted to acetyl-CoA. Acetyl-CoA is used in multiple processes, including feeding into the TCA cycle, generating ATP via the glyoxylate shunt, as a source of acetyl groups for protein modification, and to support fatty acid biosynthesis. We showed that deletion of acs (encodes acetyl-CoA synthetase; converts acetate into acetyl-CoA) significantly reduced the accumulation of rpoB and rpoS mutant subpopulations on aging colonies. Measurement of radioactive acetate uptake showed that the rate of conversion decreased in aging wild-type colonies, was maintained at a constant level in the rpoB mutant, and significantly increased in the aging rpoS mutant. Finally, we showed that the growth of subpopulations on aging colonies was greatly enhanced if the aging colony itself was unable to utilize acetate, leaving more acetate available for mutant subpopulations to use. Accordingly, the data show that the accumulation of subpopulations of rpoB and rpoS mutants on aging colonies is supported by the availability in the aging colony of acetate, and by the ability of the subpopulation cells to convert the acetate to acetyl-CoA. PMID:25275605

Bergman, Jessica M.; Wrande, Marie; Hughes, Diarmaid

2014-01-01

384

Acetate supplementation increases brain phosphocreatine and reduces AMP levels with no effect on mitochondrial biogenesis.  

PubMed

Acetate supplementation in rats increases plasma acetate and brain acetyl-CoA levels. Although acetate is used as a marker to study glial energy metabolism, the effect that acetate supplementation has on normal brain energy stores has not been quantified. To determine the effect(s) that an increase in acetyl-CoA levels has on brain energy metabolism, we measured brain nucleotide, phosphagen and glycogen levels, and quantified cardiolipin content and mitochondrial number in rats subjected to acetate supplementation. Acetate supplementation was induced with glyceryl triacetate (GTA) by oral gavage (6 g/kg body weight). Rats used for biochemical analysis were euthanized using head-focused microwave irradiation at 2, and 4h following treatment to immediately stop metabolism. We found that acetate did not alter brain ATP, ADP, NAD, GTP levels, or the energy charge ratio [ECR, (ATP+½ ADP)/(ATP+ADP+AMP)] when compared to controls. However, after 4h of treatment brain phosphocreatine levels were significantly elevated with a concomitant reduction in AMP levels with no change in glycogen levels. In parallel studies where rats were treated with GTA for 28 days, we found that acetate did not alter brain glycogen and mitochondrial biogenesis as determined by measuring brain cardiolipin content, the fatty acid composition of cardiolipin and using quantitative ultra-structural analysis to determine mitochondrial density/unit area of cytoplasm in hippocampal CA3 neurons. Collectively, these data suggest that an increase in brain acetyl-CoA levels by acetate supplementation does increase brain energy stores however it has no effect on brain glycogen and neuronal mitochondrial biogenesis. PMID:23321384

Bhatt, Dhaval P; Houdek, Heidi M; Watt, John A; Rosenberger, Thad A

2013-02-01

385

Acetate availability and utilization supports the growth of mutant sub-populations on aging bacterial colonies.  

PubMed

When bacterial colonies age most cells enter a stationary phase, but sub-populations of mutant bacteria can continue to grow and accumulate. These sub-populations include bacteria with mutations in rpoB (RNA polymerase ?-subunit) or rpoS (RNA polymerase stress-response sigma factor). Here we have identified acetate as a nutrient present in the aging colonies that is utilized by these mutant subpopulations to support their continued growth. Proteome analysis of aging colonies showed that several proteins involved in acetate conversion and utilization were upregulated during aging. Acetate is known to be excreted during the exponential growth phase but can be imported later during the transition to stationary phase and converted to acetyl-CoA. Acetyl-CoA is used in multiple processes, including feeding into the TCA cycle, generating ATP via the glyoxylate shunt, as a source of acetyl groups for protein modification, and to support fatty acid biosynthesis. We showed that deletion of acs (encodes acetyl-CoA synthetase; converts acetate into acetyl-CoA) significantly reduced the accumulation of rpoB and rpoS mutant subpopulations on aging colonies. Measurement of radioactive acetate uptake showed that the rate of conversion decreased in aging wild-type colonies, was maintained at a constant level in the rpoB mutant, and significantly increased in the aging rpoS mutant. Finally, we showed that the growth of subpopulations on aging colonies was greatly enhanced if the aging colony itself was unable to utilize acetate, leaving more acetate available for mutant subpopulations to use. Accordingly, the data show that the accumulation of subpopulations of rpoB and rpoS mutants on aging colonies is supported by the availability in the aging colony of acetate, and by the ability of the subpopulation cells to convert the acetate to acetyl-CoA. PMID:25275605

Bergman, Jessica M; Wrande, Marie; Hughes, Diarmaid

2014-01-01

386

Putative ABC Transporter Responsible for Acetic Acid Resistance in Acetobacter aceti  

PubMed Central

Two-dimensional gel electrophoretic analysis of the membrane fraction of Acetobacter aceti revealed the presence of several proteins that were produced in response to acetic acid. A 60-kDa protein, named AatA, which was mostly induced by acetic acid, was prepared; aatA was cloned on the basis of its NH2-terminal amino acid sequence. AatA, consisting of 591 amino acids and containing ATP-binding cassette (ABC) sequences and ABC signature sequences, belonged to the ABC transporter superfamily. The aatA mutation with an insertion of the neomycin resistance gene within the aatA coding region showed reduced resistance to acetic acid, formic acid, propionic acid, and lactic acid, whereas the aatA mutation exerted no effects on resistance to various drugs, growth at low pH (adjusted with HCl), assimilation of acetic acid, or resistance to citric acid. Introduction of plasmid pABC101 containing aatA under the control of the Escherichia coli lac promoter into the aatA mutant restored the defect in acetic acid resistance. In addition, pABC101 conferred acetic acid resistance on E. coli. These findings showed that AatA was a putative ABC transporter conferring acetic acid resistance on the host cell. Southern blot analysis and subsequent nucleotide sequencing predicted the presence of aatA orthologues in a variety of acetic acid bacteria belonging to the genera Acetobacter and Gluconacetobacter. The fermentation with A. aceti containing aatA on a multicopy plasmid resulted in an increase in the final yield of acetic acid. PMID:16391084

Nakano, Shigeru; Fukaya, Masahiro; Horinouchi, Sueharu

2006-01-01

387

Acetate-Mediated Growth Inhibition in Sterol 14?-Demethylation-Deficient Cells of Candida albicans  

PubMed Central

Candida albicans is a fungus thought to be viable in the presence of a deficiency in sterol 14?-demethylation. We showed in a strain of this species that the deficiency, caused either by a mutation or by an azole antifungal agent, made the cells susceptible to growth inhibition by acetate included in the culture medium. Studies with a mutant demonstrated that the inhibition was complete at a sodium acetate concentration of 0.24 M (20 g/liter) and was evident even at a pH of 8, the latter result indicating the involvement of acetate ions rather than the undissociated form of acetic acid. In fluconazole-treated cells, sterol profiles determined by thin-layer chromatography revealed that the minimum sterol 14?-demethylation-inhibitory concentrations (MDICs) of the drug, thought to be the most important parameter for clinical purposes, were practically identical in the media with and without 0.24 M acetate and were equivalent to the MIC in the acetate-supplemented medium. The acetate-mediated growth inhibition of azole-treated cells was confirmed with two additional strains of C. albicans and four different agents, suggesting the possibility of generalization. From these results, it was surmised that the acetate-containing medium may find use in azole susceptibility testing, for which there is currently no method capable of measuring MDICs directly for those fungi whose viability is not lost as a result of sterol 14?-demethylation deficiency. Additionally, the acetate-supplemented agar medium was found to be useful in detecting reversions from sterol 14?-demethylation deficiency to proficiency. PMID:9869573

Shimokawa, Osamu; Nakayama, Hiroaki

1999-01-01

388

Nomegestrol acetate-17b-estradiol for oral contraception  

PubMed Central

Oral contraceptives remain a popular method of contraception over 50 years after their introduction. While safe and effective for many women, the failure rate of oral contraception is about 8%. Concerns about the risk of venous thromboembolism continue to drive the search for the safest oral contraceptive formulations. The oral contraceptive NOMAC-E2 contains nomegestrol acetate (NOMAC) 2.5 mg + 17b-estradiol (E2) 1.5 mg. The approved dosing regimen is 24 days of active hormone, followed by a 4-day hormone-free interval. NOMAC is a progestin derived from testosterone, which has high bioavailability, rapid absorption, and a long half-life. Estradiol, though it has a lower bioavailability, has been successfully combined with NOMAC in a monophasic oral contraceptive. Two recently published randomized controlled trials demonstrate that NOMAC-E2 is an effective contraceptive, with a Pearl Index less than one pregnancy per 100 woman-years. The bleeding pattern on NOMAC-E2 is characterized by fewer bleeding/spotting days, shorter withdrawal bleeds, and a higher incidence of amenorrhea than the comparator oral contraceptive containing drospirenone and ethinyl estradiol. The adverse event profile appears to be acceptable. Few severe adverse events were reported in the randomized controlled trials. The most common adverse events were irregular bleeding, acne, and weight gain. Preliminary studies suggest that NOMAC-E2 does not seem to have negative effects on hemostatic and metabolic parameters. While no one oral contraceptive formulation is likely to be the optimum choice for all women, NOMAC-E2 is a formulation with effectiveness comparable with that of other oral contraceptives, and a reassuring safety profile. PMID:23836965

Burke, Anne

2013-01-01

389

Acetic Acid Bacteria, Newly Emerging Symbionts of Insects?  

PubMed Central

Recent research in microbe-insect symbiosis has shown that acetic acid bacteria (AAB) establish symbiotic relationships with several insects of the orders Diptera, Hymenoptera, Hemiptera, and Homoptera, all relying on sugar-based diets, such as nectars, fruit sugars, or phloem sap. To date, the fruit flies Drosophila melanogaster and Bactrocera oleae, mosquitoes of the genera Anopheles and Aedes, the honey bee Apis mellifera, the leafhopper Scaphoideus titanus, and the mealybug Saccharicoccus sacchari have been found to be associated with the bacterial genera Acetobacter, Gluconacetobacter, Gluconobacter, Asaia, and Saccharibacter and the novel genus Commensalibacter. AAB establish symbiotic associations with the insect midgut, a niche characterized by the availability of diet-derived carbohydrates and oxygen and by an acidic pH, selective factors that support AAB growth. AAB have been shown to actively colonize different insect tissues and organs, such as the epithelia of male and female reproductive organs, the Malpighian tubules, and the salivary glands. This complex topology of the symbiosis indicates that AAB possess the keys for passing through body barriers, allowing them to migrate to different organs of the host. Recently, AAB involvement in the regulation of innate immune system homeostasis of Drosophila has been shown, indicating a functional role in host survival. All of these lines of evidence indicate that AAB can play different roles in insect biology, not being restricted to the feeding habit of the host. The close association of AAB and their insect hosts has been confirmed by the demonstration of multiple modes of transmission between individuals and to their progeny that include vertical and horizontal transmission routes, comprising a venereal one. Taken together, the data indicate that AAB represent novel secondary symbionts of insects. PMID:20851977

Crotti, Elena; Rizzi, Aurora; Chouaia, Bessem; Ricci, Irene; Favia, Guido; Alma, Alberto; Sacchi, Luciano; Bourtzis, Kostas; Mandrioli, Mauro; Cherif, Ameur; Bandi, Claudio; Daffonchio, Daniele

2010-01-01

390

Photoluminescence of cellulose acetate and silica sphere composite  

NASA Astrophysics Data System (ADS)

Strong blue and green light emission has been observed from the cellulose acetate (CA) and silica sphere composite. Two different amounts of silica spheres were mixed in the CA solution to fabricate large area super-hydrophobic films. The silica spheres and CA solution ratios were 0.07:4.0 (SSCA-A) and 0.14:4.0 (SSCA-B). The milky color solution of SSCA-A and SSCA-B slowly turned to light yellow and red, respectively, with the time passed. The colors became intense yellow and red for the SSCA-A and SSCA-B, respectively, after 38 days. FTIR spectra show more absorption at 3478 cm-1 corresponding sbnd OH stretching vibration, at 2963 cm-1 caused by sbnd CH stretching vibration, at 1746 and 1713 cm-1 representing the Cdbnd O stretching vibration, and at 1100 cm-1 corresponding sbnd Rsbnd OH and Sisbnd Osbnd Si stretching vibration for CA and silica. Therefore, aged SSCA-A and SSCA-B have more sbnd OH, sbnd CH, sbnd Cdbnd O, and Sisbnd Osbnd Si groups than pure CA. UV-visible spectra show the absorption peaks at 410 nm for both SSCA-A and SSCA-B. Photoluminescence (PL) peaks were shifted toward longer wavelength with the increase of the excitation wavelength and became maximum at approximately 470 nm with excitation wavelength at 400 nm for the SSCA-A. There were two maximum luminescence peaks at 470 and 530 nm with the excitation wavelength at 400 and 470 nm, respectively, for the SSCA-B. The luminescence peak shift was due to the multiple emission center proved by the different excitation energy.

Kang, Kwang-Sun

2014-08-01

391

Water soluble cellulose acetate: a versatile polymer for film coating.  

PubMed

The objective of this study was to investigate the use of water soluble cellulose acetate (WSCA) as a film coating material for tablets. Aspirin (ASA) tablets were prepared by direct compression and coated with either WSCA or HPMC (hydroxypropyl methylcellulose) dispersions. Coatings of 1-3%, depending on the intended application, were applied to the model drug (ASA) tablets employing a side-vented coating pan. Free films of WSCA, prepared by cast method, are crystal clear and, depending on the viscosity grade, are flexible, strong and durable. WSCA has the capability of forming free films without plasticizers and the films dry at room temperature. Glass transition temperature, Tg, was determined by differential scanning calorimetry. The Tg of WSCA is significantly higher relative to HPMC. Inclusion of plasticizer lowers the Tg of WSCA and effective plasticizers were PEG 400 and glycerin. Low viscosity WSCA was more soluble in water (25-30%) relative to medium viscosity WSCA (10-15%). WSCA solutions exhibited no increase in viscosity with an increase in temperature. Samples of coated (WSCA and HPMC) tablets and uncoated ASA cores were packaged for stability studies at room and elevated temperature storage. Physical stability of ASA tablets coated with 2:1 LV: MV (low viscosity: medium viscosity) WSCA formulations was better when compared to tablets coated with HPMC. Dissolution stability of WSCA coated ASA was similar to the physical stability results. After three months at elevated temperature (35 and 45 degrees C), the WSCA coated tablets complied with USP dissolution requirements for ASA, while the HPMC coated tablets did not. There was no difference in moisture (weight) gain of ASA tablets coated with either WSCA or HPMC. The WSCA coated tablets were not sticky or tacky, while the HPMC coated tablets were tacky and stuck together. PMID:17454061

Wheatley, Thomas A

2007-03-01

392

Randomized Study Combining Interferon & Glatiramer Acetate in Multiple Sclerosis  

PubMed Central

Objective A double-blind, randomized, controlled study to determine if combined use of interferon beta-1a (IFN) 30ug IM weekly and glatiramer acetate (GA) 20mg daily is more efficacious than either agent alone in relapsing-remitting multiple sclerosis (RRMS). Methods 1008 participants were randomized and followed until the last participant enrolled completed 3 yrs. The primary endpoint was reduction in annualized relapse rate utilizing a strict definition of relapse. Secondary outcomes included time to confirmed disability, Multiple Sclerosis Functional Composite (MSFC) score and MRI metrics. Results Combination IFN + GA was not superior to the better of the single agents (GA) in risk of relapse. Both the combination therapy and GA were significantly better than IFN in reducing the risk of relapse. The Combination was not better than either agent alone in lessening confirmed EDSS progression or change in MSFC over 36 months. The combination was superior to either agent alone in reducing new lesion activity and accumulation of total lesion volumes. In a post hoc analysis, combination therapy resulted in a higher proportion of participants attaining disease activity free status (DAFS) compared to either single arm; driven by the MRI results. Interpretation Combining the two most commonly prescribed therapies for MS did not produce a significant clinical benefit over three years. An effect was seen on some MRI metrics. In a test of comparative efficacy, GA was superior to IFN in reducing the risk of exacerbation. The extension phase for CombiRx will address if the observed differences in MRI and DAFS findings predict later clinical differences. PMID:23424159

Lublin, Fred D.; Cofield, Stacey S.; Cutter, Gary R.; Conwit, Robin; Narayana, Ponnada A.; Nelson, Flavia; Salter, Amber R.; Gustafson, Tarah; Wolinsky, Jerry S.

2013-01-01

393

Acetate non-utilizing mutants of Arabidopsis: evidence that organic acids influence carbohydrate perception in germinating seedlings  

Microsoft Academic Search

A phenotypic screen was employed to isolate Arabidopsis plants that are deficient in their ability to utilize or sense acetate. The screening strategy, based on resistance to the toxic acetate analogue monofluoroacetic acid, was adapted from one that has been used successfully to identify important metabolic and regulatory genes involved in acetate metabolism in fungi. Following conventions established from the

M. A. Hooks; J. E. Turner; E. C. Murphy; I. A. Graham

2004-01-01

394

Catalytic Enantioselective Synthesis of Quaternary Stereocenters via Intermolecular C-Acylation of Silyl Ketene Acetals: Dual Activation of the  

E-print Network

in which acyl derivatives (acid halides or anhydrides) serve as the electro- philic component have not yet ketene acetal by acetic anhydride. Initially, the catalyst reacts with the anhydride to generate an acylpyridinium ion, which should be a more active acylating agent than acetic anhydride itself, along

Fu, Gregory C.

395

Direct oxidation of methane to acetic acid catalyzed by Pd2+ and Cu2+ in the presence of molecular oxygen  

E-print Network

Direct oxidation of methane to acetic acid catalyzed by Pd2+ and Cu2+ in the presence of molecular to acetic acid in concentrated sulfuric acid using a combination of Pd2+ and Cu2+ in the presence of oxygen. The conversion of methane to acetic acid has attracted recent interest as a pathway for the synthesis

Bell, Alexis T.

396

Comparison of acetate tape impression with squeezing versus skin scraping for the diagnosis of canine demodicosis.  

PubMed

This study compared the sensitivity of acetate tape impression and skin squeezing with that of deep skin scraping for the diagnosis of demodicosis in dogs. Demodex canis was detected in 100% of acetate tape impressions obtained after skin squeezing and in 90% of deep skin scrapings. There was a significant difference (P < 0.001) between the techniques in the total number of mites detected. Acetate tape impression with skin squeezing was found to be more sensitive than deep skin scraping and is an alternative diagnostic method for canine demodicosis. PMID:23106326

Pereira, A V; Pereira, S A; Gremião, I D F; Campos, M P; Ferreira, A M R

2012-11-01

397

Studies on the utilization of the 13-cis vitamin A acetate isomer by the broiler chick  

E-print Network

Chicks Experiment 1. The Effect of Feeding Vitamin A Palmitate and 4'go, and 25'go 13-cis Vitamin A Acetate on the Vitamin A Liver Storage of Broiler Chicks Experiment 2. The Effect of Feeding Vitamin A Palmitate and 4' and 25fo 13-cis Vitamin A... Acetate on the Average Weights and Feed Conversion of Broiler Chicks Experim. nt 2. The Effect of Feeding Vitamin A Palmitate and 4' and 25fo 13-cis Vitamin A Acetate on the Vitamin A Liver Storage of Broiler Chicks Experiment 3. The Effect...

Rayton, John Kenyon

2012-06-07

398

77 FR 65555 - Advisory Council for the Elimination of Tuberculosis (ACET)  

Federal Register 2010, 2011, 2012, 2013

...Advisory Council for the Elimination of Tuberculosis (ACET) In accordance with section...CDC, regarding the elimination of tuberculosis. Specifically, the Council makes...progress has been made toward eliminating tuberculosis. Matters To Be Discussed:...

2012-10-29

399

78 FR 9925 - Advisory Council for the Elimination of Tuberculosis Meeting (ACET)  

Federal Register 2010, 2011, 2012, 2013

...Advisory Council for the Elimination of Tuberculosis Meeting (ACET) In accordance with...CDC, regarding the elimination of tuberculosis. Specifically, the Council makes...progress has been made toward eliminating tuberculosis. Matters to Be Discussed:...

2013-02-12

400

78 FR 66936 - Advisory Council for the Elimination of Tuberculosis (ACET)  

Federal Register 2010, 2011, 2012, 2013

...Advisory Council for the Elimination of Tuberculosis (ACET) In accordance with section...CDC, regarding the elimination of tuberculosis. Specifically, the Council makes...progress has been made toward eliminating tuberculosis. Matters To Be Discussed:...

2013-11-07

401

75 FR 6402 - Advisory Council for the Elimination of Tuberculosis (ACET)  

Federal Register 2010, 2011, 2012, 2013

...Advisory Council for the Elimination of Tuberculosis (ACET) In accordance with section...CDC, regarding the elimination of tuberculosis. Specifically, the Council makes...progress has been made toward eliminating tuberculosis. Matters To Be Discussed:...

2010-02-09

402

75 FR 33316 - Advisory Council for the Elimination of Tuberculosis Meeting (ACET)  

Federal Register 2010, 2011, 2012, 2013

...Advisory Council for the Elimination of Tuberculosis Meeting (ACET) In accordance with...CDC, regarding the elimination of tuberculosis. Specifically, the Council makes...progress has been made toward eliminating tuberculosis. Matters To Be Discussed:...

2010-06-11

403

77 FR 27776 - Advisory Council for the Elimination of Tuberculosis Meeting (ACET)  

Federal Register 2010, 2011, 2012, 2013

...Advisory Council for the Elimination of Tuberculosis Meeting (ACET) In accordance with...CDC, regarding the elimination of tuberculosis. Specifically, the Council makes...progress has been made toward eliminating tuberculosis. Matters To Be Discussed:...

2012-05-11

404

76 FR 67459 - Advisory Council for the Elimination of Tuberculosis (ACET)  

Federal Register 2010, 2011, 2012, 2013

...Advisory Council for the Elimination of Tuberculosis (ACET) In accordance with section...CDC, regarding the elimination of tuberculosis. Specifically, the Council makes...progress has been made toward eliminating tuberculosis. Matters to be Discussed:...

2011-11-01

405

Ammonium Acetate-Basic Alumina Catalyzed Knoevenagel Condensation Under Microwave Irradiation Under Solvent-Free Condition  

Microsoft Academic Search

Ammonium acetate and basic alumina catalyzed efficiently the Knoevenagel condensation of aldehydes and ketones with active methylene compounds under solvent-free condition where olefinic products were obtained in high yields.

Saeed Balalaie; Navid Nemati

2000-01-01

406

Severe renal function impairment in adult patients acutely poisoned with concentrated acetic acid.  

PubMed

Acetic acid is a widely used organic acid with corrosive properties that depend on its concentration. If acetic acid is ingested in concentrations above 30 % it may severely damage the upper gastrointestinal tract and cause intravascular haemolysis, which can result in severe kidney and liver disorders and disseminated intravascular coagulation. In this retrospective study, we analysed acetic acid ingestion data collected at the University Clinic for Toxicology of Skopje, Macedonia from 1 January 2002 to 31 December 2011. The analysis included systemic complications, kidney damage, and the outcomes in particular. Over the ten years, 84 patients were reported at the Clinic to have ingested highly concentrated acetic acid. Twenty-eight developed kidney disorders, while the remaining 56 had no complications. Fatal outcome was reported for 11 patients, seven of whom had systemic complications and four severe gastrointestinal complications. PMID:23585201

Chibishev, Andon; Sikole, Aleksandar; Pereska, Zanina; Chibisheva, Vesna; Simonovska, Natasha; Orovchanec, Nikola

2013-01-01

407

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

PubMed Central

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

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

2012-01-01

408

Percutaneous Sclerotherapy Using Acetic Acid After Failure of Alcohol Ablation in an Intra-abdominal Lymphangioma  

SciTech Connect

We report a case of percutaneous sclerotherapy using acetic acid in a 22-year-old woman with an intra-abdominal cystic lymphangioma who was not successfully treated with ethanol despite multiple trials.

Park, Sang Woo [Konkuk University Hospital, Konkuk University School of Medicine, Department of Diagnostic Radiology (Korea, Republic of)], E-mail: psw0224@kku.ac.kr; Cha, In Ho; Kim, Kyeong Ah; Hong, Suk Joo; Park, Cheol Min; Chung, Hwan Hoon [Department of Diagnostic Radiology, Korea University School of Medicine (Korea, Republic of)

2004-09-15

409

Palladium-catalyzed substitution of (coumarinyl)methyl acetates with C-, N-, and S-nucleophiles  

E-print Network

The palladium-catalyzed nucleophilic substitution of (coumarinyl)methyl acetates is described. The reaction proceeds though a palladium ?-benzyl-like complex and allows for many different types of C-, N-, and S-nucleophiles to be regioselectively...

Chattopadhyay, Kalicharan; Fenster, Erik; Grenning, Alexander James; Tunge, Jon A.

2012-07-27

410

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

Code of Federal Regulations, 2011 CFR

...ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1390 5-Hydroxyindole acetic acid/serotonin test...

2011-04-01

411

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

...ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1390 5-Hydroxyindole acetic acid/serotonin test...

2014-04-01

412

Acetate as Sole Carbon and Energy Source for Growth of Methanosarcina Strain 227  

PubMed Central

Methanosarcina strain 227 grew rapidly and produced methane on a mineral medium containing acetate as the sole added organic substrate. Cell yields but not doubling times were affected by the presence or absence of yeast extract. Greater cell yields occurred in yeast extract medium than in mineral medium. Radioactive labeling studies showed that acetate was decarboxylated in mineral medium, as was shown previously in complex medium. The specific radioactivity of methane produced per specific acitvity of acetate added was not significantly different in yeast extract medium compared with mineral medium. Unequivocal evidence indicates that the cleavage of acetate to methane and carbon dioxide provided the energy for growth in the presence or absence of other organic compounds; these latter compounds do not serve as energy sources, electron donors, or significant sources of methane during this aceticlastic reaction. PMID:16345576

Smith, Michael R.; Mah, Robert A.

1980-01-01

413

Hydrogen peroxide resistance of Acetobacter pasteurianus NBRC3283 and its relationship to acetic acid fermentation.  

PubMed

The bacterium Acetobacter pasteurianus can ferment acetic acid, a process that proceeds at the risk of oxidative stress. To understand the stress response, we investigated catalase and OxyR in A. pasteurianus NBRC3283. This strain expresses only a KatE homolog as catalase, which is monofunctional and growth dependent. Disruption of the oxyR gene increased KatE activity, but both the katE and oxyR mutant strains showed greater sensitivity to hydrogen peroxide as compared to the parental strain. These mutant strains showed growth similar to the parental strain in the ethanol oxidizing phase, but their growth was delayed when cultured in the presence of acetic acid and of glycerol and during the acetic acid peroxidation phase. The results suggest that A. pasteurianus cells show different oxidative stress responses between the metabolism via the membrane oxidizing pathway and that via the general aerobic pathway during acetic acid fermentation. PMID:18838821

Okamoto-Kainuma, Akiko; Ehata, Yasunori; Ikeda, Manami; Osono, Takemasa; Ishikawa, Morio; Kaga, Takayuki; Koizumi, Yukimichi

2008-10-01

414

42 CFR 84.1142 - Isoamyl acetate tightness test; respirators designed for respiratory protection against dusts...  

Code of Federal Regulations, 2010 CFR

...HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Dust, Fume, and Mist; Pesticide; Paint Spray; Powered Air-Purifying High Efficiency Respirators and Combination Gas Masks § 84.1142 Isoamyl acetate...

2010-10-01

415

Effects of Exogenously Applied Indole-3-Acetic Acid (IAA) to Cotton  

E-print Network

There is a need in the cotton industry for cultivars with enhanced lint yield potential and high-quality fiber properties. Indole-3-acetic acid (IAA) is a phytohormone that is predominantly responsible for cell elongation and required for primary...

Clement, Jenny D.

2011-08-08

416

Methane production from bicarbonate and acetate in an anoxic marine sediment  

NASA Technical Reports Server (NTRS)

Methane production from C-14 labeled bicarbonate and acetate was measured over the top 28 cm of anoxic Cape Lookout Bight sediments during the summer of 1983. The depth distribution and magnitude of summed radioisotopically determined rates compare well with previous measurements of total methane production and the sediment-water methane flux. Methane production from CO2 reduction and acetate fermentation accounts for greater than 80 percent of the total production rate and sediment-water flux. Methane production from bicarbonate was found to occur in all depth intervals sampled except those in the top 2 cm, whereas significant methane production from acetate only occurred at depths below 10 cm where sulfate was exhausted. Acetate provided 20 to 29 percent of the measured methane production integrated over the top 30 cm of the sediments.

Crill, P. M.; Martens, C. S.

1986-01-01

417

Regioselective acetylation of diols and polyols by acetate catalysis: mechanism and application.  

PubMed

We propose a principle for H-bonding activation in acylation of hydroxyl groups, where the acylation is activated by the formation of hydrogen bonds between hydroxyl groups and anions. With the guidance of this principle, we demonstrate a method for the selective acylation of carbohydrates. By this method, diols and polyols are regioselectively acetylated in high yields under mild conditions using catalytic amounts of acetate. In comparison to other methods involving reagents such as organotin, organoboron, organosilicon, organobase, and metal salts, this method is more environmentally friendly, convenient, and efficient and is also associated with higher regioselectivity. We have performed a thorough quantum chemical study to decipher the mechanism, which suggests that acetate first forms a dual H-bond complex with a diol, which enables subsequent monoacylation by acetic anhydride under mild conditions. The regioselectivity appears to originate from the inherent structure of the diols and polyols and their specific interactions with the coordinating acetate catalyst. PMID:25102271

Ren, Bo; Rahm, Martin; Zhang, Xiaoling; Zhou, Yixuan; Dong, Hai

2014-09-01

418

Chronic impact of sulfamethoxazole on acetate utilization kinetics and population dynamics of fast growing microbial culture.  

PubMed

The study evaluated the chronic impact of sulfamethoxazole on metabolic activities of fast growing microbial culture. It focused on changes induced on utilization kinetics of acetate and composition of the microbial community. The experiments involved a fill and draw reactor, fed with acetate and continuous sulfamethoxazole dosing of 50 mg/L. The evaluation relied on model evaluation of the oxygen uptake rate profiles, with parallel assessment of microbial community structure by 454-pyrosequencing. Continuous sulfamethoxazole dosing inflicted a retardation effect on acetate utilization in a way commonly interpreted as competitive inhibition, blocked substrate storage and accelerated endogenous respiration. A fraction of acetate was utilized at a much lower rate with partial biodegradation of sulfamethoxazole. Results of pyrosequencing with a replacement mechanism within a richer more diversified microbial culture, through inactivation of vulnerable fractions in favor of species resistant to antibiotic, which made them capable of surviving and competing even with a slower metabolic response. PMID:24908607

Kor-Bicakci, G; Pala-Ozkok, I; Rehman, A; Jonas, D; Ubay-Cokgor, E; Orhon, D

2014-08-01

419

Selective Monoarylation of Acetate Esters and Aryl Methyl Ketones Using Aryl Chlorides  

E-print Network

Simple, efficient procedures for the monoarylation of acetate esters and aryl methyl ketones using aryl chlorides are presented. Previously, no general method was available to ensure the highly selective monoarylation of ...

Biscoe, Mark R.

420

Acetate-Bridged Platinum(III) Complexes Derived from Cisplatin  

PubMed Central

Oxidation of the acetate-bridged half-lantern platinum(II) complex, cis-[PtII(NH3)2(µ-OAc)2PtII(NH3)2](NO3)2, [1](NO3)2, with iodobenzene dichloride or bromine generates the halide-capped platinum(III) species, cis-[XPtIII(NH3)2(µ-OAc)2PtIII(NH3)2X](NO3)2, where X is Cl in [2](NO3)2, or Br in [3](NO3)2, respectively. These three complexes, characterized structurally by X-ray crystallography, feature short (? 2.6 Å) Pt–Pt separations, consistent with formation of a formal metal-metal bond upon oxidation. Elongated axial Pt–X distances occur, reflecting the strong trans influence of the metal-metal bond. The three structures are compared to those of other known dinuclear platinum complexes. A combination of 1H, 13C, 14N, and 195Pt NMR spectroscopy was used to characterize [1]2+–[3]2+ in solution. All resonances shift downfield upon oxidation of [1]2+ to [2]2+ and [3]2+. For the platinum(III) complexes, the 14N and 195Pt resonances exhibit decreased linewidths by comparison to those of [1]2+. Density functional theory (DFT) calculations suggest that the decrease in 14N linewidth arises from a diminished electric field gradient (EFG) at the 14N nuclei in the higher valent compounds. The oxidation of [1](NO3)2 with the alternative oxidizing agent, bis(trifluoroacetoxy) iodobenzene, affords the novel tetranuclear complex, cis-[(O2CCF3)PtIII(NH3)2(µ-OAc)2PtIII(NH3)(µ-NH2)]2(NO3)4, [4](NO3)4, also characterized structurally by X-ray crystallography. In solution, this complex exists as a mixture of species, the identities of which are proposed. PMID:22946515

Wilson, Justin J.

2012-01-01

421

The feeding value of water and acetic acid reconstituted sorghum grain for lactating dairy cows  

E-print Network

THE FEEDING VALUE OF WATER AND ACETIC ACID RECONSTITUTED SORGHUM GRAIN FOR LACTATING DAIRY COWS A Thesis by DAVID HEINIE BADE Submitted to the Graduate College of Texas ASM University in partial fulfillment of the requirement for the degree... of MASTER OF SCIENCE May 1972 Major Subject: Animal Nutrition THE FEEDING VALUE OF WATER AND ACETIC ACID RECONSTITUTED SORGHUM GRAIN FOR LACTATING DAIRY COWS A Thesis by DAVID HEINIE BADE Approved as to style and content by: C ' man o Committee...

Bade, David Heinie

2012-06-07

422

Interspecies acetate transfer influences the extent of anaerobic benzoate degradation by syntrophic consortia  

SciTech Connect

Benzoate degradation by an anaerobic, syntrophic bacterium, strain SB, in coculture with Desulfovibrio strain G-11 reached a threshold value which depended on the amount of acetate added, and ranged from about 2.5 to 29.9 {mu}M. Increasing acetate concentrations also uncompetitively inhibited benzoate degradation. The apparent V{sub max} and K{sub m} for benzoate degradation decreased with increasing acetate concentration, but the benzoate degradation capacity (V{sub max}/K{sub m}) of cell suspensions remained comparable. The addition of an acetate-using bacterium to cocultures after the threshold was reached resulted in the degradation of benzoate to below the detection limit. Mathematical simulations showed that the benzoate threshold was not predicted by the inhibitory effect of acetate on benzoate degradation kinetics. With nitrate instead of sulfate as the terminal electron acceptor, no benzoate threshold was observed in the presence of 20 mM acetate even though the degradation capacity was lower with nitrate than with sulfate. When strain SB was grown with a hydrogen-using partner that had a 5-fold lower hydrogen utilization capacity, a 5 to 9-fold lower the benzoate degradation capacity was observed compared to SB/G-11 cocultures. The Gibb`s free energy for benzoate degradation was less negative in cell suspensions with threshold compared to those without threshold. These studies showed that the threshold was not a function of the inhibition of benzoate degradation capacity by acetate, or the toxicity of the undissociated form of acetate. Rather a critical or minimal Gibb`s free energy may exist where thermodynamic constraints preclude further benzoate degradation.

Warikoo, V.; McInerney, M.J.; Suflita, J.M. [and others

1997-03-01

423

Preparation of transparent, electrically conducting ZnO film from zinc acetate and alkoxide  

Microsoft Academic Search

Very uniform and transparent zinc oxide thin films doped with aluminium and indium were fabricated by the dip-coating technique using solutions prepared by the ethanolamine method. As starting materials, zinc acetate and zinc n-propoxide were used. Zinc acetate and propoxide are soluble in PriOH in the presence of diethanolamine, although they are hardly soluble without the amine. The prepared solutions

Y. Ohya; H. Saiki; Y. Takahashi

1994-01-01

424

Release of indomethacin from pH-sensitive pullulan acetate microsphere  

Microsoft Academic Search

We studied the pH-sensitive indomethacin (IND) delivery system using pullulan. Hydrophobic pullulan acetate was prepared by\\u000a chemical modification of hydrophilic pullulan and pullulan acetate microsphere was made by a solvent evaporation method. The\\u000a size of microspheres was below 5 ?m, and the drug loading efficiencies of microspheres were approximately 78 and 65% at the\\u000a initial amount of drug 40 and

Kun Na; Young-II Jeong; Ki-Young Lee

1997-01-01

425

Antispasmodic and spasmogenic effects of Scolymus hispanicus and taraxasteryl acetate on isolated ileum preparation.  

PubMed

Taraxasteryl acetate was identified as the major triterpenoid of the ethanolic extract of the root bark of Scolymus hispanicus L. Antispasmodic and spasmogenic effects of the ethanolic extract, its fractions, taraxasteryl acetate, and a fluid extract of this plant were tested on isolated rat ileum preparations. The strong biphasic responses observed suggested a possible lithuretic activity of the compounds and the fractions tested. PMID:17252378

Kirimer, N; Tunalier, Z; Can Ba?er, K H; Cingi, I

1997-12-01

426

Antispasmodic and spasmogenic effects of Scolymus hispanicus and taraxasteryl acetate on isolated ileum preparations.  

PubMed

Taraxasteryl acetate (1) was identified as the major triterpenoid of the ethanolic extract of the root bark of Scolymus hispanicus L. Antispasmodic and spasmogenic effects of the ethanolic extract, its fractions, taraxasteryl acetate, and a fluid extract of this plant were tested on isolated rat ileum preparations. The strong biphasic responses observed suggested a possible lithuretic activity of the compounds and the fractions tested. PMID:9434612

Kirimer, N; Tunalier, Z; Ba?er, K H; Cingi, I

1997-12-01

427

11C-Acetate PET Imaging in Patients with Multiple Sclerosis  

PubMed Central

Background Activation of glial cells is a cardinal feature in multiple sclerosis (MS) pathology, and acetate has been reported to be selectively uptaken by astrocytes in the CNS. The aim of this study was to investigate the efficacy of PET with 11C-acetate for MS diagnosis. Materials and Methods Six patients with relapsing-remitting MS and 6 healthy volunteers (HV) were enrolled. The 11C-acetate brain uptake on PET was measured in patients with MS and HV. Volume-of-interest analysis of cerebral gray and white matter based on the segmentation technique for co-registered MRI and voxel-based statistical parametric analysis were performed. Correlation between 11C-acetate uptake and the lesion number in T1- and T2- weighted MR images were also assessed. Results The standardized uptake value (SUV) of 11C-acetate was increased in both white and gray matter in MS patients compared to HV. Voxel-based statistical analysis revealed a significantly increased SUV relative to that in the bilateral thalami (SUVt) in a broad area of white matter, particularly in the subcortical white matter of MS patients. The numbers of T2 lesions and T1 black holes were significantly correlated with SUV of 11C-acetate in white and gray matter. Conclusions The 11C-acetate uptake significantly increased in MS patients and correlated to the number of MRI lesions. These preliminary data suggest that 11C-acetate PET can be a useful clinical examination for MS patients. PMID:25369426

Shimosegawa, Eku; Okuno, Tatsusada; Koda, Toru; Sugimoto, Tomoyuki; Mochizuki, Hideki; Hatazawa, Jun; Nakatsuji, Yuji

2014-01-01

428

Simultaneous determination of uric acid and ascorbic acid using glassy carbon electrodes in acetate buffer solution  

Microsoft Academic Search

The present work reports the simultaneous determination of uric acid (UA) and ascorbic acid (AA) in 0.2M, pH 4.0, acetate buffer solution using glassy carbon (GC) electrode by square wave voltammetry. Selective detection of UA in the presence of 200-fold excess of AA is achieved at the GC electrode in acetate buffer solution. The GC electrode separates the voltammetric signal

S. Abraham John

2005-01-01

429

Molecular properties of 4-substituted indole-3-acetic acids affecting pea pericarp elongation  

Microsoft Academic Search

Pea (Pisum sativum L.) fruit naturally contain the auxins, indole-3-acetic acid (IAA) and 4-chloroindole-3-acetic acid (4-Cl-IAA). However, only 4-Cl-IAA can substitute for the seeds in maintaining pea fruit growth in planta. The importance of the substituent at the 4-position of the indole ring was tested by comparing the molecular properties of 4-X-IAA (X = H, Me, Et, F, or Cl)

Dennis M. Reinecke; Jocelyn A. Ozga; Nebojša Ili?; Volker Magnus; Biserka koji?-Prodi?

1999-01-01

430

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

PubMed Central

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

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

1998-01-01

431

Selective extraction of succinic acid from binary mixture of succinic acid and acetic acid  

Microsoft Academic Search

In production of succinic acid by fermentation, succinic acid and acetic acid are co-produced. To purify the succinic acid from binary-acid mixture of succinic acid and acetic acid, the tertiary amine-based extraction was used. In 1-octanol, the selectivity for succinic acid was proportional to the chain length of tertiary amine. But, the distribution of acids into organic phase was low

Yeon Ki Hong; Won Hi Hong; Ho Nam Chang

2000-01-01

432

Electrochemical generation of manganese (III) at glassy carbon electrode in acetic acid  

Microsoft Academic Search

Conditions were established for the electrochemical generation of manganese(III) at glassy carbon in acetic acid. In the oxidation of manganese-(II) in potassium acetate supporting electrolyte high current efficiencies were achieved in a wide range of current densities at the working electrode, whereas in the presence of sodium perchlorate a successful generation of manganese(III) could be performed only at low current

Tibor J. Pastor; Vojka V. Antonijevi?

1990-01-01

433

Production of Isoamyl Acetate from Sugar Beet Molasses by Williopsis saturnus var. saturnus  

Microsoft Academic Search

J. Inst. Brew. 114(1), 34-38, 2008 Three strains of Williopsis saturnus var. saturnus were employed for the production of natural isoamyl acetate (the character im- pact compound of banana flavour) using sugar beet molasses as the carbon source and batch cultivation at 25°C under anaerobic conditions. Of the three strains, strain HUT 7087 was the best producer of isoamyl acetate,

Murat Yilmaztekin; Huseyin Erten; Turgut Cabaroglu

434

Transport of solutes through calix[4]pyrrole-containing cellulose acetate films  

Microsoft Academic Search

Films of cellulose acetate containing different concentrations of meso-octamethyl-porphyrinogen (calix[4]pyrrole) were prepared and characterized using UV–vis and FTIR spectroscopy, DSC and SEM. Incorporation of calix[4]pyrrole into cellulose acetate leads to a decrease in the degree of hydrophilicity of the polymeric matrix. However, a slight increase in the percentage of water uptake of the polymer is found with an increase of

A. J. M. Valente; A. Jiménez; A. C. Simões; H. D. Burrows; A. Ya. Polishchuk; V. M. M. Lobo

2007-01-01

435

Differential effects of the microbial metabolite, acetic acid, on sprouting of aquatic plant propagules  

Microsoft Academic Search

Subterranean vegetative propagules are important life cycle stages for some species of rooted aquatic plants. Sediments contain numerous compounds resulting from anaerobic degradation of organic matter, including acetic acid. Tubers, turions, and winter buds of Hydrilla verticillata (L.f.) Royle, Potamogeton gramineus L., and Potamogeton pectinatus L. were exposed to acetic acid concentrations from 0 to 696 mmol l?1 for 1–8

David F. Spencer; Gregory G. Ksander

1995-01-01

436

Hydrogen-exchange reaction of alkyl halides with formic and acetic acids  

Microsoft Academic Search

1.An investigation was made of the hydrogen exchange of alkyl halides in media differing in dielectric constant, namely formic and acetic acids.2.Tertiary halides (chloride, bromides, and iodides) undergo hydrogen exchange with formic acid-d, whereas secondary alkyl halides do not undergo hydrogen exchange under the same conditions. Tertiary chlorides do not undergo hydrogen exchange with acetic acid-d, whereas under the same

D. N. Kursanov; E. V. Bykova; V. N. Setkina

1959-01-01

437

Neutralization of acids and bases in subcritical and supercritical water: acetic acid and HCl  

Microsoft Academic Search

Acid-base titrations for the KOH-acetic acid or NH3-acetic acid systems were monitored with the optical indicator 2-naphthoic acid at 350 °C and 34 MPa, and those for the HCl?Cl? system with acridine at 380 °C and up to 34 MPa (5000 psi). KOH remains a much stronger base than NH4OH at high temperature. From 298 K to the critical temperature

Keith P. Johnston; Jerzy B. Chlistunoff

1998-01-01

438

Dissociation of acetic acid in 50 mass % ethylene carbonate-water from 20 to 55°C  

Microsoft Academic Search

The dissociation constant of acetic acid in 50 mass % ethylene carbonate-water solvents has been determined at eight temperatures from 20 to 55°C by emf measurements of cells without liquid-junction containing hydrogen electrodes and silver-silver chloride electrodes. Acetic acid is weaker in the mixed solvent than in pure water. At 25°C, pK is 5.645 as compared with 4.756 in water,

J-C Hallé; Roger G. Bates

1975-01-01

439

Radiolabeled acetate kinetics and tricarboxylic acid cycle flux in the rat heart  

Microsoft Academic Search

Positron-emitting (1-¹¹C)acetate has been proposed as a tracer for noninvasive study of regional myocardial oxidative metabolism in humans with positron emission tomography (PET). To examine the relationship between tissue tracer kinetics and tricarboxylic acid (TCA) cycle flux, (1-¹⁴C)acetate was administered as a bolus to Langendorf-perfused rat hearts and effluent ¹⁴COâ and labeled metabolites measured. ¹⁴COâ cleared monoexponentially between 5 and

M. Schwaiger; H. R. Schelbert; M. E. Phelps; A. Nguyen; D. B. Buxton

1987-01-01

440

Population dynamics of acetic acid bacteria during traditional wine vinegar production  

Microsoft Academic Search

The population dynamics of acetic acid bacteria in traditional vinegar production was determined in two independent vinegar plants at both the species and strain level. The effect of barrels made of four different woods upon the population dynamics was also determined. Acetic acid bacteria were isolated on solid media and the species were identified by RFLP-PCR of 16S rRNA genes

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

2010-01-01

441

Insect sex pheromones: Evaporation rates of alcohols and acetates from natural rubber septa  

Microsoft Academic Search

The half-lives (t1\\/2) of alcohol sex pheromones, 1-alkanols, acetate sex pheromones, and an epoxide (disparlure) were determined on natural rubber septa. Thet1\\/2 values for the homologous alcohols from decanol to heptadecanol increased regularly from 2.2 to 1117 days, but thet1\\/2 of octadecanol was 609 days. Thet1\\/2 values of (Z)7-, (E)7-, and (Z)9-tetradecen-1-ol acetates were 154, 168, and 199 days, respectively,

L. I. Butler; L. M. McDonough

1981-01-01

442

Synthesis and Characterization of Main Chain Degradable Poly(amide-imide)s with Acetal Unit  

Microsoft Academic Search

A series of main chain degradable poly(amide-imide)s 7 were prepared from acetal-containing diimide-dicarboxylic acid 5 with various aromatic diamine monomers 6 by the direct polycondensation in NMP using triphenyl phosphite\\/pyridine as condensing agents. The novel diimide-dicarboxylic acid 5 bearing 2-trifluoromethylphenyl substituted acetal unit was synthesized by the condensation reaction of amine compound 4 with trimellitic anhydride. All the polymers were

Li Li; Mitsutoshi Jikei; Masa-Aki Kakimoto

2003-01-01

443

Controlling grey and blue mould diseases of apple fruits using acetic acid vapours  

Microsoft Academic Search

The effect of acetic acid vapours at three application times on grey and blue moulds on the incidence of apple fruits was studied. Acetic acid vapour at 6 µl\\/l caused complete inhibition of linear growth and spore germination of Botrytis cinerea and Penicillium sp. The most effective concentration was AA at 4 µl\\/l, which reduced spore germination and linear growth by more

Yehia Omar Fotouh

2009-01-01

444

Zymomonas with improved ethanol production in medium containing concentrated sugars and acetate  

DOEpatents

Through screening of a Zymomonas mutant library the himA gene was found to be involved in the inhibitory effect of acetate on Zymomonas performance. Xylose-utilizing Zymomonas strains further engineered to reduce activity of the himA gene were found to have increased ethanol production in comparison to a parental strain, when cultured in mixed-sugars medium comprising xylose, and, in particular, in the presence of acetate.

Caimi, Perry G. (Kennett Square, PA); Chou, Yat-Chen (Lakewood, CO); Franden, Mary Ann (Centennial, CO); Knoke, Kyle (Newark, DE); Tao, Luan (Havertown, PA); Viitanen, Paul V. (West Chester, PA); Zhang, Min (Lakewood, CO); Zhang, Yuying (New Hope, PA)

2011-03-01

445

A novel fermentation process for calcium magnesium acetate (CMA) production from cheese whey  

Microsoft Academic Search

A novel, anaerobic fermentation process is developed to produce calcium magnesium acetate (CMA) from cheese whey. CMA can\\u000a be used as a noncorrosive road deicer. It poses no environmental threats and has many advantages over road salt. A coculture\\u000a consisting of homolactic and homoacetic bacteria was used to convert whey lactose to lactate and then to acetate in a continuous,

Shang-Tian Yang; I-Ching Tang; Hui Zhu

1992-01-01

446

Sodium nonivamide acetate: A non-pungently antinociceptive capsaicin derivative with unusual anti-inflammatory properties  

Microsoft Academic Search

1.1. Bradykinin-induced vascular pain in conscious rats, hyperalgesia in the rat hind paw, rat hind paw edema induced by compound 48\\/80 and carrageenin and dye exudation induced by intraperitoneal injection of 0.7% acetic acid in mice were all inhibited by sodium nonivamide acetate (SNA).2.2. Collagen and arachidonic acid-induced rabbit platelet aggregations were inhibited by SNA and capsaicin. In human platelet

Jwu-Mau Yang; Chao-Shun Tang; Kwong-Leung Yu; Yu-Chiao Yang; Wen-Chang Chang; Ing-Jun Chen

1996-01-01

447

Characterization of poly(ethylene- co-vinyl acetate) (EVA) filled with low grade magnesium hydroxide  

Microsoft Academic Search

Low-grade magnesium hydroxide (LG-MH) is a solid by-product that undergoes an endothermic decomposition in the temperature range of 300–750°C. Due to its thermal behaviour and its lower cost relative to pure Mg(OH)2, it was studied as a non-halogenated flame retardant filler in a 28% vinyl acetate (VA) content poly(ethylene-co-vinyl acetate) matrix. The solid was characterized by XRF and the crystalline

A. I. Fernández; L. Haurie; J. Formosa; J. M. Chimenos; M. Antunes; J. I. Velasco

2009-01-01

448

Responses of Plasma Acetate Metabolism to Hop (Humulus lupulus L.) in Sheep  

Microsoft Academic Search

An isotope dilution method using (1-13C)sodium (Na) acetate was conducted to determine the effect of feeding hop (Humulus lupulus L.) residues on plasma acetate metabolism in six adult crossbred sheep. The sheep were fed 63 g\\/kg BW0.75\\/d of either mixed hay (MH-diet) of orchardgrass (Dactylis glomerata L.) and reed canarygrass (Phalaris arundinacea L.) at a 60:40 ratio or MH-diet and

Mohammad Al-Mamun; Kunio Goto; Sota Chiba; Hiroaki Sano

449

A new anaerobic, sporing, acetate-oxidizing, sulfate-reducing bacterium, Desulfotomaculum (emend.) acetoxidans  

Microsoft Academic Search

A new strictly anaerobic, polarly flagellated, sporing, acetate-oxidizing, sulfate-reducing bacterium was isolated from anaerobic fresh or sea water mud samples. The oxidation of acetate to CO2 is stoichiometrically linked to the formation of H2S from sulfate. Ethanol, butanol and butyrate are also used. Hydrogen, lactate or pyruvate are not used as electron donors; organic substances are not fermented. A cytochrome

Friedrich Widdel; Norbert Pfennig

1977-01-01

450

Effects of feeding hygromycin B and chlormadinone acetate on performance of a commercial laying stock  

E-print Network

and chlormadinone 81 acetate feeding. Experiment 2. EFFECTS OF FEEDING HYGROEYCIN B AND CHLOBMADINONE ACETATE ON PERFORMANCE OF A COMMERCIAL LAYING STOCK. Introduction A number of antibiotic products have been tested and reported to bring about improvement... for three weeks only. REVIEM' OF LITERATURE Several reports have appeared in the literature concerning the addition of low levels of certain antibiotics to poultry feeds for purposes of improving the growth rates and egg prcduction and in most cases...

Abd El-Maguid, Ferial Saad

2012-06-07

451

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

Microsoft Academic Search

We have determined the atmospheric concentrations of formic and acetic acid in the gas phase, in aerosols, and in rain during the dry season (July--August 1985) in the Amazonia region of Brazil. At ground level the average concentrations of gas phase formic and acetic acid were 1.6 +- 0.6 and 2.2 +- 1.0 ppb, respectively. The diurnal behavior of both

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

1988-01-01

452

Acetate Sol-Gel Synthesis of PMN Ceramics from Nb-Ethyleneglycol-Tartarate Complex  

Microsoft Academic Search

PbMgNb(OAc)x(OR)y precursor was prepared from Pb and Mg acetates by dissolution in acetic acid (AcOH) and by mixing with Nb-ethyleneglycol-tartarate (Pechini) complex. The sol was formed after hydrolysis by various addition of water at 80°C and it was transformed by polycondensation to PMN two-phase gel. By the calcination of gel at the temperature of 500°C for 2 hours, the two-phase

J. Brian?in; H. Bruncková; L'. Medvecký

2005-01-01

453

Hemodiafiltration with Endogenous Reinfusion with and without Acetate-Free Dialysis Solutions: Effect on ESA Requirement  

Microsoft Academic Search

Background: Hemofiltrate reinfusion (HFR) is a form of hemodiafiltration (HDF) in which replacement fluid is constituted by ultrafiltrate from the patient ‘regenerated’ through a cartridge containing hydrophobic styrene resin. Bicarbonate-based dialysis solutions (DS) used in routine hemodialysis and HDF contain small quantities of acetate (3–5 mM) as a stabilizing agent, one of the major causes of intradialytic hypotension. Acetate-free (AF)