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Dypbukt Jeannette M - - 2005
We describe a new assay for the chlorination activity of myeloperoxidase and detection of chloramines. Chloramines were detected by using iodide to catalyze the oxidation of either 3,3',5,5'-tetramethylbenzidine (TMB) or dihydrorhodamine to form strongly absorbing or fluorescent products, respectively. With TMB as little as 1 muM taurine chloramine could be ...
Suzuki Hiroshi - - 2005
We conducted simultaneous liver and peripheral blood micronucleus assays in young rats with seven rodent hepatocarcinogens-4,4'-methylenedianiline (MDA), quinoline, o-toluidine, 4-chloro-o-phenylenediamine (CPDA), dimethylnitrosamine (DMN), p-dimethylaminoazobenzene (DAB), and di(2-ethylhexyl)phthalate (DEHP)-and two mutagenic chemicals-kojic acid and methylmethanesulfonate (MMS). Quinoline, DMN, and DAB were positive in the liver assay, while o-toluidine, kojic acid, DAB, ...
Jovanović Vladan - - 2005
We used two species of light-requiring seeds, Paulownia tomentosa, which have absolute light requirement (no germination in darkness), and Stellaria media seeds, which germinate in darkness to a certain extent because of presence of preformed active phytochrome, to obtain results strongly suggesting that gibberellic acid nitrite stimulates seed germination via ...
Layton Abigail N - - 2005
This study investigates the Salmonella effector protein SopA. We show that in Salmonella enterica serovar Dublin-infected cells, SopA(1-347) fused to two carboxy-terminal hemagglutinin tags partially colocalized with mitochondria. Transfection of eukaryotic cells with a panel of constructs encoding truncated versions of SopA identified that amino acids 100 to 347 were ...
Knize Mark G - - 2005
A group of heterocyclic amines that are mutagens and rodent carcinogens form when meat is cooked to medium and well-done states. The precursors of these compounds are natural meat components: creatinine, amino acids, and sugars. Defined model systems of dry-heated precursors mimic the amounts and proportions of heterocyclic amines found ...
Panzella Lucia - - 2005
Exposure of 400 microM (-)-epigallocatechin-3-O-gallate (EGCG), the main polyphenolic constituent of green tea, to equimolar concentrations of nitrite ions in 0.5 M HCl at 37 degrees C resulted in the formation of a distinct pattern of products that were trapped as phenazine derivatives by treatment with o-phenylenediamine. Repeated chromatographic fractionation ...
Takahashi Asaka - - 2005
3-Allyl-5-substituted 2-thiohydantoins (ATH-amino acids) derived from allyl isothiocyanate and amino acids can inhibit the mutagenicity of 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) in the Salmonella assay. In this report, we studied possible mechanisms for the inhibition using rat liver S9 in assays for ethoxyresorufin O-deethylase (EROD), a marker activity for cytochrome P450 1A (CYP1A), ...
Lansky Ephraim Philip - - 2005
Four pure chemicals, ellagic acid (E), caffeic acid (C), luteolin (L) and punicic acid (P), all important components of the aqueous compartments or oily compartment of pomegranate fruit (Punica granatum), and each belonging to different representative chemical classes and showing known anticancer activities, were tested as potential inhibitors of in ...
Huang Winn-Jung - - 2005
The major disinfection by-products (DBPs) resulting from ozone treatment of polluted surface water were investigated. By-products of either health concern or which may contribute to biological instability of treated drinking water were investigated. The major DBPs were analyzed in two fractions: carbonyl compounds and brominated organic compounds. The natural organic ...
Lu Hsu-Feng - - 2005
It is well documented that N-acetyltransferase (NAT) plays a key role in the N-acetylation of arylamine compounds. Ellagic acid was demonstrated to elicit dose-dependent bacteriostatic activity and inhibition of N-acetylation of 2-aminofluorene (AF). N-acetylation of AF in S. aureus was determined by high preformance liquid chromatography. The apparent values of ...
Yilmaz Meral - - 2005
The antimicrobial activity and the MIC values of the diethyl ether, acetone, chloroform, petroleum ether, and ethanol extracts of the lichen Hypogymnia tubulosa and its 3-hydroxyphysodic acid constituent have been investigated against some microorganisms. At least one of the extracts or 3-hydroxyphysodic acid showed antimicrobial activity against Aeromonas hydrophila, Bacillus ...
Geetha Thiraviam - - 2005
The present study has been performed to evaluate the antimutagenic activity of quercetin, ascorbic acid and their combination against an oxidative mutagen. An effort was also made to correlate this activity to the in vitro antioxidant activity of these agents. Antimutagenicity testing was done in Ames Salmonella Assay system using ...
Wada K - - 2004
The generation of 2-(2',4'-dihydroxybenzoyl) benzoic acid (DHBBA) and 2-(2',4'-dihydroxy-3',5'-diiodobenzoyl) benzoic acid (DHDIBBA) during the manufacture of erythrosine (Food Red No. 3) was examined. DHBBA is formed as an intermediate during the synthesis of fluorescein, and as fluorescein is produced, it is gradually consumed. However, under inappropriate reaction conditions, it remains ...
Kinashi Yuko - - 2004
We investigated the biological effects of the long-lived radicals induced following neutron irradiation. It has been reported that radiation-induced long-lived radicals were scavenged by post-irradiation treatment of ascorbic acid (Koyama, 1998). We studied the effects of ascorbic acid acting as a long-lived radical scavenger on cell killing and mutagenicity in ...
Ochi Takafumi - - 2004
Diphenylarsinic acid [DPAs(V)], a degradation product of diphenylcyanoarsine or diphenylchloroarsine, both of which were developed as chemical warfare agents, was investigated in terms of its capacity to induce cytotoxic effects, numerical and structural changes of chromosomes, and abnormalities of centrosome integrity and spindle organizations in conjunction with the effects of ...
Kenney Stephen J - - 2004
Caenorhabditis elegans, a free-living nematode found in soil, has been shown to ingest human enteric pathogens, thereby potentially serving as a vector for preharvest contamination of fruits and vegetables. A study was undertaken to evaluate the efficacy of cleaners and sanitizers in killing Salmonella enterica serotype Newport in the gut ...
Van Immerseel F - - 2004
The most common source of Salmonella infections in humans is food of poultry origin. Salmonella enterica serovar Enteritidis has a particular affinity for the contamination of the egg supply. In this study, the medium-chain fatty acids (MCFA), caproic, caprylic, and capric acid, were evaluated for the control of Salmonella serovar ...
Murkovic M - - 2004
Heterocyclic aromatic amines (HAs) are mutagenic and carcinogenic substances that are formed in significant amounts during heating of meat or fish at temperatures of at least 150 degrees C. To investigate the chemistry lying behind the formation of these harmful substances model systems were established. The first aim was to ...
Bordas M - - 2004
A model system based on a commercial meat flavour was used to evaluate the formation of heterocyclic amines, simulating the application of this seasoning in household cooking. The effects of different treatments in both dry and aqueous conditions were studied. The lyophilized meat flavour extract was heated at temperatures ranging ...
Sharkey Freddie H - - 2004
Competitive reverse transcription polymerase chain reaction (cRT-PCR) was used to quantify the toxin-encoding mRNA production of a Clostridium botulinum type E strain in media containing either sorbic acid or sodium nitrite. A 10-fold reduction in toxin mRNA production and a 25-fold reduction in the proportion of toxin mRNA to total ...
Buschini Annamaria - - 2004
Mutagenicity of drinking water is due not only to industrial, agricultural and urban pollution but also to chlorine disinfection by-products. Furthermore, residual disinfection is used to provide a partial safeguard against low level contamination and bacterial re-growth within the distribution system. The aims of this study were to further evaluate ...
Kitis Mehmet - - 2004
Peracetic acid is a strong disinfectant with a wide spectrum of antimicrobial activity. Due to its bactericidal, virucidal, fungicidal, and sporicidal effectiveness as demonstrated in various industries, the use of peracetic acid as a disinfectant for wastewater effluents has been drawing more attention in recent years. The desirable attributes of ...
Skrivanová E - - 2004
The susceptibility of Salmonella spp. to 15 fatty acids was determined in vitro in cultures grown on glucose. Antimicrobial activity was expressed as IC50 (a concentration at which only 50% of the initial glucose in cultures was utilized). Caprylic acid was the only acid inhibiting glucose utilization. In cultures of ...
He Ling-yan - - 2004
PM2.5 samples were collected by a three-stage cascade impactor at two kinds of Chinese restaurants to characterize fine organic particulate matter from Chinese cooking sources. Major individual organic compounds have been quantified by GC/MS, including series of alkanes, n-alkanoic acids, n-alkanals, alkan-2-ones and PAHs. Alkanes and ketones make up a ...
Van Immerseel F - - 2004
Short-chain fatty acids (SCFA) are widely used as feed additives in poultry for the control of pathogenic bacteria, such as Salmonella enteritidis. Recently, a new range of products was developed in which SCFA are encapsulated in mineral carriers, resulting in a slow release during the transport of these carriers through ...
Calicioglu Mehmet - - 2003
This study evaluated the influence of pre-drying marinade treatments on inactivation of acid-adapted or nonadapted Salmonella on beef jerky during preparation, drying and storage. The inoculated (five-strain composite, 6.0 log CFU/cm2) slices were subjected to the following marinades (24 h, 4 degrees C) prior to drying at 60 degrees C ...
Ferguson Lynnette R - - 2003
We have determined the abilities of (E)-ferulic acid, (E)-p-coumaric acid and (E,E)-5-5-dehydrodiferulic acid to protect against different types of mutation in a simple bacterial model. These antimutagenic properties were compared with those of the related compound curcumin, and also with those of an extract containing hydroxycinnamic acids obtained by the ...
Espigares E - - 2003
The ability of six mixtures to neutralize glutaraldehyde, o-phthalaldehyde and peracetic acid was tested using four reference strains: Pseudomonas aeruginosa CIP A22, Escherichia coli CIP 54127, Staphylococcus aureus CIP 53154, and Enterococcus faecium CIP 5855. Glutaraldehyde was the hardest to neutralize, and peracetic acid the easiest. The most effective mixture ...
Beeharry Neil - - 2003
Polyunsaturated fats are the main target for lipid peroxidation and subsequent formation of mutagenic metabolites, but diets high in saturated fats are more strongly associated with adverse health effects. We show that the common saturated fatty acid, palmitic acid, is a potent inducer of DNA damage in an insulin-secreting cell ...
Richardson Susan D - - 2003
Using gas chromatography/mass spectrometry (GC/MS), we investigated the formation of disinfection byproducts (DBPs) from high bromide waters (2 mg/L) treated with chlorine or chlorine dioxide used in combination with chlorine and chloramines. This study represents the first comprehensive investigation of DBPs formed by chlorine dioxide under high bromide conditions. Drinking ...
Ow Yin-Yin - - 2003
Gallic acid and its structurally related compounds are found widely distributed in fruits and plants. Gallic acid, and its catechin derivatives are also present as one of the main phenolic components of both black and green tea. Esters of gallic acid have a diverse range of industrial uses, as antioxidants ...
Liu Qin-Tao - - 2003
Organic films on an impervious surface (window glass) were sampled at paired indoor-outdoor sites in July 2000 and characterized for their paraffinic and polar organic compositions along an urban-rural transect. Four classes of polar compounds (C11-C31 aliphatic monocarboxylic, C6-C14 dicarboxylic, nine aromatic polycarboxylic, and five terpenoid acids) constituted between 81 ...
Henderson Jeffrey P - - 2003
Oxidative damage to DNA has been implicated in carcinogenesis during chronic inflammation. Epidemiological and biochemical studies suggest that one potential mechanism involves myeloperoxidase, a hemeprotein secreted by human phagocytes. In this study, we demonstrate that human neutrophils use myeloperoxidase to oxidize uracil to 5-chlorouracil in vitro. Uracil chlorination by myeloperoxidase ...
Mikulásová Mária - - 2003
The effect of lignin on cytotoxicity, mutagenicity and SOS response induced by 4-nitroquinoline-N-oxide (4NQO), 3-(5-nitro-2-furyl)acrylic acid (5NFAA), 2-nitrofluorene (2NF) as well as hydrogen peroxide was investigated in bacterial assay systems, i.e. the Ames test with Salmonella typhimurium TA98, TA100, TA102 and the SOS chromotest with Escherichia coli PQ37. Lignin preparations ...
Calicioglu Mehmet - - 2003
This study was undertaken to evaluate the survival of acid-adapted and nonadapted Salmonella cultures inoculated after drying on beef jerky that had been treated with marinades before drying at 60 degrees C for 10 h. Beef slices were (i) not treated prior to refrigeration at 4 degrees C for 24 ...
Fukushi K - - 2003
The presence of pathogenic microorganisms in municipal waste sludge may create a serious outbreak of water borne diseases if the sludge is used for agricultural purpose. An attempt to decrease the number of pathogenic microorganisms, Salmonella spp. using a simulated acid-phase anaerobic digester was tested in a laboratory-scale batch experiment. ...
Carvalho Pinto-Silva C R - - 2003
Some toxins present in the marine environment are capable of inducing mutagenicity and/or carcinogenicity. Among these toxins, okadaic acid (OA) is gaining considerable interest since it induces DNA based modifications at low concentrations and accumulates in filter-feeding marine animals, including those used for human consumption. This study aims to evaluate ...
Fiume Monice Zondlo - - 2003
Diisopropyl Dimer Dilinoleate, Dicetearyl Dimer Dilinoleate, Diisostearyl Dimer Dilinoleate, Dioctyl Dimer Dilinoleate, Dioctyldodecyl Dimer Dilinoleate, and Ditridecyl Dimer Dilinoleate are diesters of their respective alcohols and dilinoleic acid. They function as skin-conditioning agents in a variety of cosmetic products at concentrations around 10%, but may be used at concentrations up ...
Takiya Toshiyuki - - 2003
Ames test is the most popular method of assessing mutagenicity using Salmonella typhimurium as an indicator. Recently, sequence analyses have been introduced for the investigation of mutation mechanisms. Most revertants (>70%) carry 2-bp deletion within an 8-bp CG repeat in hisD (hotspot mutation) in the Ames test using S. typhimurium ...
Panzella Lucia - - 2002
In acetate buffer, pH 4, at room temperature, nitrite ions can mediate an unusual decarboxylative conjugation of caffeic acid with glutathione leading to novel isomeric 2-(3,4-dihydroxyphenyl)-2-S-glutathionylacetaldehyde oximes. These results hint at a possible role of endogenous and/or dietary glutathione in the mechanisms by which caffeic acid can affect the burden ...
Sharma Seema - - 2002
The gas-phase acidities of adenine, 9-ethyladenine, and 3-methyladenine have been investigated for the first time, using computational and experimental methods to provide an understanding of the intrinsic reactivity of adenine. Adenine is found to have two acidic sites, with the N9 site being 19 kcal mol(-1) more acidic than the ...
Huixian Zou - - 2002
MX was widely considered as one of the most important disinfection by-products (DPBs) and as the strong carcinogen in the chlorinated drinking water. Some model compounds which have been classified into four families were chlorinated at laboratory conditions. MX was produced only in the chlorinated substituted aromatic aldehydes and amino ...
Kitano K - - 2002
Although potassium sorbate (PS), ascorbic acid and ferric or ferrous salts (Fe-salts) are used widely in combination as food additives, the strong reactivity of PS and oxidative potency of ascorbic acid in the presence of Fe-salts might form toxic compounds in food during its deposit and distribution. In the present ...
Zaneveld Lourens J D - - 2002
OBJECTIVE: To assess the contraceptive properties, antimicrobial activity, and safety of mandelic acid condensation polymer (SAMMA). DESIGN: Experimental study of SAMMA's in vitro and in vivo properties. SETTING: Academic research laboratories. PATIENT(S): Healthy volunteers for semen donation in an academic research environment. INTERVENTION(S): Inhibition of sperm function indicators, conception, sexually ...
Kaur K - - 2002
The antimutagenic effect of benzene, chloroform, acetone and methanol fractions from Terminalia arjuna, a well-known medicinal plant, was determined against Acid Black dye, 2-aminofluorene (2AF) and 4-nitro-o-phenylenediamine (NPD) in TA98 Frameshift mutagen tester strain of Salmonella typhimurium. Among the different fractions, the antimutagenic effect of acetone and methanol fractions was ...
Kaya Bülent - - 2002
The ability of ascorbic acid (Vitamin C) to modulate the genotoxic action of several mutagens was investigated in the wing spot test of Drosophila melanogaster. In this assay, 3-day-old transheterozygous larvae for the multiple wing hairs (mwh, 3-0.3) and flare (flr, 3-38.8) genes were treated with three reference mutagenic compounds, ...
Matsuoka Hiroki - - 2002
The structure of the yellow pigment found in salted radish roots was studied. It was found that 1-(2-thioxopyrrolidin-3-yl)-1,2,3,4-tetrahydro-beta-carboline-3-carboxylic acid (TPCC) was unstable under neutral pH, and was easily converted into the yellow pigment. The yellow pigment was isolated and identified as 2-[3-(2-thioxopyrrolidin-3-ylidene)methyl]-tryptophan (TPMT) by IR, MS, 1H-, and 13C-NMR spectroscopy. ...
Roy Molay Kumar - - 2002
The antimutagenic activity of protein-constituting amino acids except histidine on the mutagenicity of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) was investigated in vitro using Salmonella typhinurium TA-100 as an indicator bacterium (Ames test), and concentrations (IC50) of amino acids that inhibit 50% of the mutagenecity were measured. Cysteine was found to be most active ...
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 ...
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