Search Results
Results 201 - 250 of 714
< 1 2 3 4 5 6 7 8 9 10 >
Takahama Umeo - - 2002
Human saliva contained 4-hydroxyphenylacetic acid (HPA) (2-10 microM) and nitrite (60-300 microM). HPA was nitrated to 4-hydroxy-3-nitrophenylacetic acid (NO2HPA) when HPA and sodium nitrite were mixed at pH 1.0. NO2HPA was also formed when saliva was incubated under acidic conditions. These results suggest that salivary HPA is nitrated to NO2HPA ...
Turbic A - - 2002
Specific strains of lactic acid bacteria possessing antimutagenic properties are suggested to remove mutagenic contaminants of foods through binding and an investigation of their substrate specificity is required. The ability of Lactobacillus rhamnosus strains GG and LC-705 in viable and non-viable (heat- and acid-treated) forms to remove both dietary mutagens ...
Figueroa C C - - 2002
Hydroxamic acids (Hx) contained in wheat are active mutagens which play an important role in the defence of the plant against aphids. Random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR) dominant markers were used to assess genetic variability in the aphid Sitobion avenae (Fabricius) in relation to hydroxamic acid levels in ...
Kargalioglu Yahya - - 2002
We analyzed the cytotoxicity and mutagenicity of the drinking water disinfection by-products (DBPs) bromoform (BF), bromoacetic acid (BA), dibromoacetic acid (DBA), tribromoacetic acid (TCA), chloroform (CF), chloroacetic acid (CA), dichloroacetic acid (DCA), trichloroacetic acid (TCA), 3-chloro-4-(dichloromethyl)-5-hydroxy-2[5H]-furanone (MX), and potassium bromate (KBrO3) in Salmonella typhimurium strains TA98, TA100, and RSJ100 +/- ...
Gawande Purushottam V - - 2002
Salmonellae are the most frequently reported cause of outbreaks of food-borne gastroenteritis in the United States. In clinical trials, the oral infective dose (ID) for healthy volunteers was estimated to be approximately 1 million cells. However, in reports from various outbreaks, the ID of Salmonella species associated with solid foods ...
Pharis R P - - 2001
The bioactivity of 25-hydroxybrassinolide, (25S)- and (25R)-26-hydroxybrassinolide, (25S)- and (25R)-25,26-dihydroxybrassinolide, and of (25R)-25,26-epoxybrassinolide was tested in the rice leaf lamina inclination assay. The 25- and (25S)-26-hydroxy derivatives are known metabolites of the naturally-occurring phytohormone brassinolide, whereas the other compounds are novel, but closely related, congeners. When tested alone, all showed ...
Stampi S - - 2001
AIMS: Evaluation of the efficiency of peracetic acid in the disinfection of wastewater in a large treatment plant. METHODS AND RESULTS: Over a period of 18 months 30 sample collections were made, each consisting of three samples taken from: raw incoming sewage, secondary effluent (after 10-12 h) and secondary effluent ...
Yen G C - - 2001
Our aim was to determine the antimutagenic activity of various solvent extracts from an herb Mesona procumbens Hemsl, normally called Hsian-tsao in China. We also investigated the relationships between the special components in the water extract of Hsian-tsao (WEHT) and the antimutagenic activity. It was found that the extracts at ...
Rossman L A - - 2001
Little is known about how the growth of halogenated disinfection by-products (DBPs) in drinking water is affected by time spent in a distribution system. Experiments were performed to compare the rate of trihalomethane and haloacetic acid production in a simulated pipe environment to that observed for the same water held ...
Sharma M - - 2001
Studies were done to determine the survival of salmonellae in orange juice as affected by fortification with calcium. Four brands of commercially pasteurized orange juice fortified with calcium (350 mg/240-ml serving) and nonfortified juice were inoculated separately with three types of inocula: strains of Salmonella Muenchen (inoculum 1), serotypes of ...
Kubena L F - - 2001
Young chickens are more susceptible to Salmonella colonization than older chickens that have developed resistance with age as native microflora become established. Elevated concentrations of cecal propionic acid and total volatile fatty acids (VFA) have been observed by many researchers to be indicators of establishment of anaerobic microflora and protection ...
Yoshimoto M - - 2001
The antimutagenicity of the 3-sophoroside-5-glucoside of cyanidin and 3-sophoroside-5-glucoside of peonidin, the anthocyanin derivatives deacylated from the 3-(6,6'-caffeylferulylsophoroside)-5-glucoside of cyanidin (YGM-3) and 3-(6,6'-caffeylferulylsophoroside)-5-glucoside of peonidin (YGM-6) which had been purified from the sweetpotato with purple-colored flesh, was investigated by using Salmonella typhimurium TA 98. A comparison of the antimutagenicity between ...
Nelson G M - - 2001
Haloacetic acids are by-products of drinking water disinfection. Several compounds in this class are genotoxic and have been identified as rodent hepatocarcinogens. Enzymes produced by the normal intestinal bacteria can transform some promutagens and procarcinogens to their biologically active forms. The present study was designed to investigate the influence of ...
Weller R - - 2001
AIMS: Nitric oxide is generated from sweat nitrite in the acidic environment of the skin surface and is thought to contribute to protection against infection. This study examined the sensitivity of Trichophyton mentagrophytes, T. rubrum, Candida albicans, Streptococcus pyogenes, Staphylococcus aureus and Propionibacterium acnes to acidified nitrite. METHODS AND RESULTS: ...
Wu S C - - 2001
Since the fume of cooking oil has been reported to increase the risk of lung cancer, the objectives of this study were to evaluate the mutagenicity and to find the mutagens in the fumes of peanut oil heated to the smoke point. Peanut oil prepared from roasted peanut kernel showed ...
Sottofattori E - - 2001
Nitrosation of propranolol under standard conditions recommended by the World Health Organization (10mM propranolol hydrochloridre, 40mM sodium nitrite, pH 3.5) was performed in the absence and in the presence of benzoic acid and of twelve mono-, di- and tri-hydroxybenzoic acids, added to the nitrosation mixture in concentrations ranging from 2 ...
Belicová A - - 2001
Naturally occurring plant phenolics, p-coumaric acid (PA), caffeic acid (CA), ferulic acid (FA) and gentisic acid (GA) (25-100 nmol/L) had protective effects on acridine orange (AO; 216 mumol/L)- and ofloxacin (3 mumol/L)-induced genotoxicity in Salmonella typhimurium. FA, GA and CA exhibited a significant concentration-dependent protective effect against the genotoxicity of ...
Fiume Z - - 2001
Lecithin is a naturally occurring mixture of the diglycerides of stearic, palmitic, and oleic acids, linked to the choline ester of phosphoric acid, commonly called phosphatidylcholine. Hydrogenated Lecithin is the product of controlled hydrogenation of Lecithin. Bilayers of these phospholipids in water may form liposomes, a spherical structure in which ...
Straukas J - - 2001
DL-p-chlorophenylalanine (PCPA) and its derivatives were evaluated for genotoxic effects using Escherichia coli and Bacillus subtilis strains lacking various DNA-repair mechanisms in spottest and in suspension test. The mutagenic activity of studied compounds was determined by the Ames test. Reverse mutation test was performed with Salmonella typhimurium strains TA98, TA100, ...
Ho C C - - 2001
Following exposure of rats to the arylamine carcinogen 2-aminofluorene, DNA-carcinogen adducts were found in the liver and bladder target tissues, and also in circulating leucocytes. This work investigated the effect of ellagic acid on arylamine (2-aminofluorene and p-aminobenzoic acid) acetylations in rat leucocytes. Evidence is presented that rat mononuclear leucocytes ...
Lanigan R S - - 2001
Polyethylene Glycol (PEG)-6, -8, and -20 Sorbitan Beeswax are ethoxylated derivatives of Beeswax that function as surfactants in cosmetic formulations. Only PEG-20 Sorbitan Beeswax is currently reported to be used, at concentrations up to 11%. Few data on the PEGs Sorbitan Beeswax ingredients were available. This safety assessment relied upon ...
Jiménez-Cisneros B E - - 2001
The removal of helminth ova, faecal coliforms, Salmonella and protozoan cysts by the application of physicochemical treatment processes to municipal wastewater and sludge was studied. In the first case, the advanced primary treatment (APT) process was studied, as well as filtration of the APT effluent. The APT sludge was treated ...
Ferrand C - - 2000
Sorbic acid (E200) and its salts (potassium and calcium sorbate: E202 and E203) are allowed for use as preservatives in numerous processed foods. Sorbic acid had a conjugated system of double bonds which makes it susceptible to nucleophilic attack, sometimes giving mutagenic products. Under conditions typical of food processing (50-80 ...
Venkov P - - 2000
The potential toxic and mutagenic action of 2,4-dichlorophenoxyacetic acid has been studied in different test systems, and the obtained results range from increased chromosomal damage to no effect at all. We reexamined the effect of this herbicide by simultaneous using three tests based on yeast, transformed hematopoietic, and mouse bone ...
Cutter C N - - 2000
A study was conducted to determine if slaughter interventions currently used by the meat industry are effective against Salmonella Typhimurium definitive type 104 (DT 104) and two non-O157:H7 enterohemorrhagic Escherichia coli (EHEC). Three separate experiments were conducted by inoculating prerigor beef surfaces with a bovine fecal slurry containing Salmonella Typhimurium ...
Krizková L - - 2000
The mutagenicity (bleaching activity) of ofloxacin (43 microM) and acridine orange (AO) (13.5 microM) in Euglena gracilis is inhibited by plant phenolics. Caffeic acid (CA), p-coumaric acid (PCA), ferulic acid (FA) and gentisic acid (GA) (25, 50, 100 and 250 microM) exhibited a significant concentration-dependent inhibitory effect against ofloxacin-induced mutagenicity, ...
Ferrand C - - 2000
Sorbic acid (E200) and its salts (potassium and calcium sorbate: E202 and E203) are allowed for use as preservatives in numerous processed foods. Sorbic acid has a conjugated system of double bonds which makes it susceptible to nucleophilic attack, sometimes giving mutagenic products. Under conditions typical of food processing (50-80 ...
Karekar V - - 2000
Antimutagens and anticarcinogens are known to play an important role in combating the action of factors involved in the etiology of cancer. It is expected that inhibitors of mutagenesis also act as inhibitors of carcinogenesis. In the present study, two short-term genotoxicity assays, namely the Ames assay and the Drosophila ...
Akyol D - - 2000
We performed a prospective randomized study to compare the potential genotoxic effects of metronidazole and nalidixic acid which they are used in the treatment of Trichomonas vaginalis infection. 20 patients with Trichomonas vaginalis infections participated in this study. 14 patients with vaginal trichomoniasis were treated with therapeutic doses of metronidazole ...
Marhaba T F - - 2000
Dissolved organic matter (DOM) influences many aspects of water treatment, including the formation of potentially harmful disinfection by-products (DBPs) when disinfectants are applied. DOM from a conventional surface water treatment plant (WTP) in Northern New Jersey was isolated and fractionated using resin adsorption chromatography into six different fractions. These fractions ...
Pais P - - 2000
Mixtures of the free amino acids, creatine and glucose, were dry-heated to model the potential formation of heterocyclic amines in meats. The formation of the mutagenic amine IFP (determined to be 2-amino-(1,6-dimethylfuro[3,2-e]imidazo[4,5-b])pyridine) was investigated by varying heating time, heating temperature, and precursors. With an optimized mixture of glutamine, creatine, and ...
Urbansky E T - - 2000
Many potable water disinfection byproducts (DBPs) that result from the reaction of natural organic matter (NOM) with oxidizing chlorine are known or suspected to be carcinogenic and mutagenic. The Ames assay is routinely used to assess an overall level of mutagenicity for all compounds in samples from potable water supplies ...
Beier R C - - 2000
Many strains of Salmonella typhimurium studied in our lab demonstrated marked differences in the pathogenicity for guinea pig, chicken and Hela cells. As a result, a pathogenic strain of S. typhimurium, strain 9SR2, was evaluated for lipophilic components that may be associated with virulence using gas chromatography/mass spectrometry. The hydroxylated ...
Chen S C - - 2000
Tannic acid and its hydrolysed products such as ellagic acid, gallic acid and propyl gallate were tested for mutagenicities using Ames Salmonella tester strains TA98 and TA100. Also, the antimutagenic activities of these compounds against a number of direct mutagens including 2-nitrofluorene (2-NF), 4,4'-dinitro-2-biphenylamine, 1-nitropyrene, 1,3-dinitropyrene, 2-nitro-p-phenylenediamine, 3-nitro-o-phenylenediamine, 4-nitro-o-phenylenediamine were ...
Foltínová P - - 2000
The hereditary bleaching test on Euglena gracilis was used for detecting extranuclear mutations. The highest bleaching activity (induction of the chloroplast-free mutants) was shown by the 6-R-3-formylchromones. On the other hand, bleaching-inactive 6-R-3-formylchromone acylhydrazones (derived from gallic and salicylic acids), added at sufficient concentrations in the case of chloroplast mutagenesis ...
Keck B - - 2000
Under microaerophilic conditions Salmonella typhimurium LT2 synthesizes cobalamin, during which 5,6-dimethylbenzimidazole is formed from riboflavin. We report here that in an anoxic environment S. typhimurium did not form cobalamin, but rather adenylcobamide, 2-methyladenylcobamide, and cobyric acid. This indicated that S. typhimurium, like other microorganisms that synthesize 5,6-dimethylbenzimidazole from riboflavin, requires ...
Vachálková A - - 2000
This paper deals with determination of potential carcinogenic and inhibitory activity of 10 compounds isolated from the ethanolic extract of Lilium candidum L. perfonned by DC polarography. The series of investigated compounds consisted of two spirostanol saponins, two pyroline derivatives, jatropham and its glucoside, flavonol kaempferol, 2-fenylethyl-alpha-L-arabinopyranosyl-(1-->6)-beta-D-glucopyranoside, 2-phenylethylpalmitate and methylsuccinic ...
Obrecht-Pflumio S - - 1999
Ochratoxin A (OTA) was, up to now, believed to be non-mutagenic in the classical Salmonella typhimurium reverse mutation test. This was confirmed using rat liver microsomal fractions with the strains, TA1535, TA1538 and TA98, and up to 1210 micrograms/plate, utilizing an Ames microtest. However, using mice kidney microsomal fractions as ...
Elbetieha A - - 1999
The Bacillus subtilis ATCC 6633 strain synthesizes a mutagenic metabolite from sodium azide and O-acetylserine. Mutagenicity of azide was decreased in growth media containing 10(-4) M glutathione, L-cysteine or L-djenkolic acid whereas dithiothritol (DTT) added at the same concentration did not reduce the mutagenicity of azide. Likewise, glutathione, L-cysteine, L-djenkolic ...
Kevekordes S - - 1999
Naturally occurring substances were tested for genotoxicity using a modified laboratory protocol of the Escherichia coli PQ37 genotoxicity assay (SOS chromotest) in the presence and in the absence of an exogenous metabolizing system from rat liver S9-mix. Aristolochic acid I, II, the plant extract aristolochic acid and psoralene were genotoxic; ...
Colin Slaughter J - - 1999
Three closely related 4-hydroxy-3(2H)-furanones have been found in a range of highly cooked foodstuffs where they are important flavour compounds with aroma threshold values as low as 20 micrograms kg-1 water (approximately 0.14 mumol l-1). The compounds are formed mainly as a result of the operation of the Maillard reactions ...
Hori Y - - 1999
The concentrations and compositions of free fatty acids (FFAs) in human bile, especially of inhibitory free fatty acids (IFFAs), were analyzed in terms of anti-mutagenic effects in relation to the mutagenic activity of bile. Bile samples were collected from patients with cholelithiasis residing in either Niigata or Kochi prefectures of ...
Hour T C - - 1999
The antimutagenic properties of various tea extracts (green tea, pauchong tea, oolong tea and black tea) and their components including (-)-epigallocatechin-3-gallate (EGCG), gallic acid and caffeine were examined by the Ames test. The antimutagenic activity of the green tea extract against N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), folpet and monocrotophos was greater than those ...
Breathnach A S - - 1999
Azelaic acid is a naturally occurring straight-chained 9-carbon atom dicarboxylic acid which is non-toxic, non-teratogenic, and non-mutagenic. Its antiproliferative and cytotoxic effect on a variety of tumoural cell lines in culture, due to inhibition of mitochondrial oxidoreductases of the respiratory chain and of enzymes concerned with DNA synthesis is well ...
Singer V L - - 1999
SYBR Green I nucleic acid gel stain is an unsymmetrical cyanine dye developed for sensitive detection of nucleic acids in electrophoretic gels. Its mechanism of nucleic acid binding is not known, whereas the most commonly used nucleic acid gel stain, ethidium bromide, is a well-characterized intercalator. We compared the mutagenicity ...
Lyi S M - - 1999
Octopine-type Ti plasmids such as pTi15955, pTiA6 and pTiR10 direct the catabolism of at least eight compounds called opines that are released from crown gall tumours. Four of these compounds are denoted mannityl opines, each of which possesses a D-mannityl substituent on the nitrogen atom of either glutamate or glutamine. ...
Müller B - - 1999
Contaminants in biotechnologically manufactured L-Tryptophan (Trp) are suspected to be responsible for the outbreak of an unknown autoimmune disease in 1989. The contaminants, found in Trp-lots of a Japanese manufacturer, are classified in EMS-correlated and non EMS-correlated substances. Up to now six EMS-correlated substances are known. One of these compounds ...
Kaur S - - 1998
A tannin fraction (TC-E) from the dried fruit pulp of Terminalia chebula was obtained by successfully extracting with 95% ethyl alcohol and ethyl acetate. TC-E was subjected to silica gel chromatography which yielded four fractions, viz., TC-EI, TC-EII, TC-EIII and TC-EIV. Thin layer chromatography (TLC) and 13C-NMR revealed that TC-EI ...
Franzén R - - 1998
The mutagenic activities of several chlorinated butenoic acids, recently identified in chlorinated drinking waters, were determined by the Salmonella microsome assay. The Salmonella typhimurium tester strains TA98, TA100, and TA104 were used without S9 mix. The results from the investigation showed that (Z)-2-chloro-3-(dichloromethyl)-4-oxobutenoic acid (MX, in the open form) was ...
Vereskuns G - - 1998
The mutagenic activity of threo-9,10-dichlorostearic acid, one of the chlorinated fatty acids identified in fish lipids, was examined in the Ames/Salmonella test. No mutagenic activity was found on any of the Salmonella typhimurium strains TA 98, TA 100 and TA 102, either with or without S9 activation. On the other ...
< 1 2 3 4 5 6 7 8 9 10 >