SEARCH · Search PubMed

Results for “Pyruvic Acid”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,045 records · Page 58Linked to original sources

PubMed1998

Antimutagenic properties of probiotic bacteria and of organic acids.

Antimutagenic activities of live and killed cells of 6 strains of Lactobacillus acidophilus and 9 strains of bifidobacteria and of organic acids usually produced by these probiotic bacteria were determined using 8 potent chemical mutagens and promutagens. The mutagens and promutagens used were N-methyl, N'-nitro, N-nitrosoguanidine; 2-nitroflourene; 4-nitro-O-phenylenediamine; 4-nitroquinoline-N-oxide; Aflatoxin-B; 2-amino-3-methyl-3H-imidazoquinoline; 2-amino-1-methyl-6-phenyl-imidazo (4,5-b) pyridine, and 2-amino-3-methyl-9H-pyrido (3,3-6) indole. The mutagenicity of these mutagens and antimutagenic activity of probiotic bacteria against the mutagens were determined according to the Ames TA-100 assay using a mutant of Salmonella typhimurium. Efficiency of bacterial cells in binding or inhibiting these mutagens was also investigated. Live cells of probiotic bacteria showed higher antimutagenic activity and their efficiency in inhibiting the mutagens was better than killed bacterial cells. Live bacterial cells bound or inhibited the mutagens permanently, whereas killed bacteria released mutagens upon extraction with dimethyl sulfoxide. Among the organic acids, butyric acid showed highest inhibition of mutagens followed by acetic acid. Lactic and pyruvic acids did not show appreciable levels of inhibition.

Bifidobacterium↗

PubMedDate not supplied

Phenol degradation and toxicity assessment upon biostimulation to an indigenous Rhizobium Ralstonia taiwanensis.

This study provides a first attempt from a toxicological perspective to put forward, in general terms and explanations, combined toxic interactions and biostimulation strategy upon nutrient medium to Ralstonia taiwanensis for bioremediation. Dose-response analysis clearly revealed that most of the supplemented nutrients tested (except for gluconic acid) synergistically interact with chronic toxicity to phenol, especially at low doses. Acute toxicity based upon adaptation lag is a more appropriate indicator for comparative analysis of toxicity due to similar toxic ranking at almost all effective concentrations. In addition, comparison upon acute and chronic toxicity for various nutrient media also suggests in parallel that acute toxicity is more significant than chronic toxicity possibly as the result of a more sensitive response of adaptation lag to growth in different media. Feasibility of adding extra nutrient substrates (e.g., phenol, gluconic acid, yeast extract, pyruvic acid, acetic acid, and glycerol) to stimulate proliferation of phenol degraders for better phenol degradation performance was also assessed. The results show that using acetic acid as the augmented nutrient source might be the most feasible biostimulation strategy for phenol degradation.

Biodegradation, Environmental↗

PubMed2005

Simultaneous determination of mono- and dicarboxylic acids, omega-Oxo-carboxylic acids, midchain ketocarboxylic acids, and aldehydes in atmospheric aerosol samples.

This paper describes a method for the simultaneous determination of monocarboxylic acids (C6-C34), dicarboxylic acids (C2-C24), omega-oxo-carboxylic acids (C2-C9), ketocarboxylic acids (pyruvic and pinonic acid), and select aldehydes (glyoxal, methylglyoxal, and nonanal) in atmospheric particles. Quantification of these compounds gives information on important chemical characteristics of aerosols for source apportioning of aerosol organics and for studying atmospheric processes leading to secondary organic aerosol formation. These target analytes were determined as their butyl ester or butyl acetal derivatives using gas-chromatography mass spectrometry. The method is modified from a method described by Kawamura. Kawamura's original method involved a water extraction step, which practically restricted the method to the determination of only those compounds that are water-soluble. Our method eliminates the water extraction step and combines extraction and derivatization of the target compounds in one step. A mixture of hexane/butanol/BF3 simultaneously derivatizes the polar function groups (i.e., -COOH, -C=O) and extracts the target analytes from the aerosol filter substrates. A prominent advantage of our method is improved recoveries for the more volatile analytes in the target compound classes as a result of eliminating the water evaporation step. Recoveries better than 66% were obtained for the target analytes, including the relatively volatile ones. This improvement for the light species has allowed detection of a new midchain ketocarboxylic acid, 4-oxopentanoic acid, which would have escaped detection by the Kawamura method because of its high susceptibility to evaporative loss. Examples are presented to demonstrate the use of this method in analysis of ambient aerosol samples.

Aerosols↗

PubMed2003

Current mechanistic understanding of thiamin diphosphate-dependent enzymatic reactions.

The mechanism of thiamin diphosphate-dependent enzymatic reactions is discussed, concentrating on two enzymes involved in decarboxylating pyruvic acid, the yeast pyruvate decarboxylase and the pyruvate dehydrogenase multienzyme complex from Escherichia coli. The availability of high-resolution X-ray structures for several thiamin diphosphate-dependent enzymes, the use of site-specifically substituted protein variants (resulting from site-directed mutagenesis), the development of model reactions for the various putative intermediates, and the application of new mechanistic tools in solution have all contributed to a much better understanding of the role of the protein component in catalysis. Perhaps the most important advance in our understanding of these mechanisms concerns the role of the 4'-aminopyrimidine component of the coenzyme, widely ignored prior to the publication of the X-ray results. The current view is that the two aromatic rings both contribute to catalysis, perhaps carrying out an intramolecular proton transfer to initiate the various reactions, an ability that makes this coenzyme virtually unique among coenzymes.

Catalysis↗

PubMed2006

Photodegradation of toluene over TiO(2-x)N(x) under visible light irradiation.

We report the photooxidation of toluene over nitrogen doped TiO(2) (TiO(2-x)N(x)) under visible light irradiation. The photocatalytic oxidation of toluene in air over TiO(2-x)N(x) powders was studied using diffuse reflectance Fourier transform infrared spectroscopy (DRIFTS), gas chromatography (GC), ion chromatography (IC), and gas chromatography mass spectrometry (GC-MS), focusing on the photocatalytic decomposition processes of toluene. Results obtained indicate that toluene, weakly adsorbed on the catalyst surface, is initially photooxidized to benzaldehyde which adsorbs onto the TiO(2-x)N(x) surface more strongly, leading to the formation of ring-opening products such as carboxylic acids and aldehydes. No gaseous intermediates were detected during the photooxidation. Major intermediates adsorbed at the catalyst surface were oxalic acid, (COOH)(2), acetic acid, CH(3)COOH, formic acid, HCOOH, and pyruvic acid, CH(3)COCOOH, whereas more complicated carboxylic species, including propionic acid, CH(3)CH(2)COOH, isovaleric acid, (CH(3))(2)CHCH(2)COOH, and succinic acid, (CH(2)COOH)(2), were also found in the early stage of the photooxidation. These intermediate products were gradually photodegraded to CO(2) and H(2)O under visible light irradiation.

Catalysis↗

PubMed1984

Cross-reactions of polysaccharides of fungi, molds, and yeasts in anti-pneumococcal and other antisera.

Cross-reactions of a number of glycans and polysaccharides isolated from fungi, molds, and yeasts in anti-pneumococcal and other antisera are tabulated and discussed insofar as possible with relation to the chemical structures of the cross-precipitating substances and the polysaccharidic antigens giving rise to the reactive antibodies. For example, the slime of Physarum polycephalum precipitated antisera to pneumococcal type 4 and Klebsiella type K1. The polysaccharides of type 4 and K1 contain pyruvic acid in acetal linkage on hydroxyls 2 and 3 of sugars. Therefore, pyruvic acid was looked for and found in Physarum slime. Numerous other relations between chemical structure and immunological specificity are given.

Cross Reactions↗

PubMed1989

Trichloroacetic acid peels revisited.

Trichloroacetic acid (TCA) is a time-honored peeling agent that has no known systemic toxicity. Recent interest in reversing the effects of actinic damage has led to the utilization of combination therapies. Retinoic acid, solid CO2, pyruvic acid, Jessner's formula, and other agents have been used to increase the effectiveness of TCA and enhance peeling results. Repetitive peels with low concentrations of TCA can be effective for areas prone to scarring.

Administration, Topical↗

PubMed2005

Bench-to-bedside review: Amelioration of acute renal impairment using ethyl pyruvate.

Inflammation and oxidative stress cause renal impairment. Renal failure exacerbates the effect of oxidative stress on many organ systems. Antioxidants can prevent or treat renal failure in various experimental models and clinical situations. Pyruvate is an endogenous antioxidant with beneficial effects in animal models of oxidative stress. Because sodium pyruvate rapidly degrades in solution, a simple derivative of pyruvic acid, namely ethyl pyruvate, has been investigated as a therapeutic agent in preclinical studies. Ethyl pyruvate reduces organ system damage in ischaemia/reperfusion injury and haemorrhagic and endotoxic shock, at least in part through its antioxidant action. In addition, ethyl pyruvate appears to have direct beneficial effects on cytokine expression and proinflammatory gene regulation. The effect is long lasting and, importantly, even when it is administered after the onset of inflammation it can ameliorate organ damage and improve survival. Ethyl pyruvate is a widely used as a food additive and was shown to be safe in phase I clinical trials. We suggest ethyl pyruvate warrants further evaluation in the management of acute renal impairment.

Acute Kidney Injury↗

PubMed1981

Uterine enzyme changes in thyroidectomized rats at parturition.

Rats were thyroidectomized at different stages of gestation and killed at parturition. Acid phosphatase of uterine horns was significantly (P < 0.05) lower in animals thyroidectomized at later stages of pregnancy, whereas alkaline phosphatase was significantly lower in those thyroidectomized earlier as compared to intact pregnant animals. The activities of glutamic oxaloacetic acid and glutamic pyruvic acid transaminases also showed significant alterations in some of the thyroidectomized animals. These 4 enzymes were also studied in the cervix but the changes showed a less distinct pattern.

Acid Phosphatase↗

PubMed1986

Comparison of pancreatic exocrine secretion via endogenous secretin by intestinal infusion of hydrochloric acid and monocarboxylic acid in anesthetized piglets.

The secretory response of the exocrine pancreas via endogenous secretin (IRS) by intraduodenal instillation of hydrochloric acid (HCl) and various monocarboxylic acid solutions was studied in anesthetized piglets. The secretion induced by HCl solutions of various concentrations containing 250 mM NaCl occurred when pH of the solutions was lower than 1.5. After instillation of the HCl solution of pH 1.0, juice flow and protein output increased 26 times and 9 times, respectively, as compared with basal levels. Such pancreatic responses paralleled an increase in plasma IRS concentration in the portal vein. The pancreatic response induced by a lactic acid solution occurred when pH of the solutions was lower than 3.8. The juice flow and protein output stimulated by a lactic acid solution of 250 mM and pH 2.0 were 16 and 8 times higher than the basal levels. The responses to the lactic acid solution of pH 2.0 increased concentration dependently, and were followed by an increase in IRS concentration in the portal vein. The pancreatic exocrine responses induced by other monocarboxylic acid solutions (250 mM) of pH 2.0 were in the following order: formic acid greater than lactic acid greater than pyruvic acid much greater than acetic acid greater than butyric acid greater than propionic acid. Lactamide, an analogous substance of lactic acid, did not evoke any pancreatic secretion. The results indicate the possibility that pancreatic exocrine response induced by HCl is dependent upon hydrogen ion, while the response induced by monocarboxylic acid is not always dependent on dissociation constant of acid.

Anesthesia↗

PubMed1956