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Durán N N Instituto de Quimica, Biological Chemistry Laboratory, Universidade Estadual de Campinas, C.P. 6154, 13081-970 SP, Campinas, CEP, - - 1994
Radio-isotope studies indicated not only that L-tryptophan can serve as carbon source for synthesis of the trypanocide, violacein by Chromobacterium violaceum (BB-78 strain) but also that isatin and indole 3-acetic acid are both important metabolic intermediates. Using 3-indolyl [2-(14)C] and [1-(14)C] acetic acid, it was found that the carboxylic carbon ...
Surh Y J - - 1994
Heat treatment of foods containing reducing sugars and amino acids during cooking or sterilization triggers a sequence of non-enzymatic reactions collectively known as the Maillard reaction. 5-Hydroxymethylfurfural (HMF), one of the major intermediate products in the Maillard reaction, has been found to possess cytotoxic, genotoxic and tumorigenic activities, but the ...
Barale R - - 1994
The mutagenicity of airborne particulate matter collected in 17 towns of Italy in 1990 was assessed using the Ames test. The mutagenicity of crude extract correlated with amount of lead, suggesting the direct contribution of gasoline car exhausts. Moreover, the mutagenicity correlated with particulate matter amounts. An inverse correlation with ...
Iwado H - - 1994
Previous studies on several samples of urban air-borne particulates showed that the long-chain fatty acids present in these samples can interfere with the measurement of mutagenicity of the particulates with the Salmonella assay. To explore whether this phenomenon is a general, fatty acid contents and the mutagenicity (with Salmonella typhimurium ...
DeMarini D M - - 1994
We performed three types of studies to evaluate the genotoxicity of the chlorinated organic solvent perchloroethylene (PERC or tetrachloroethylene) and its volatile metabolites, trichloroacetyl chloride (TCAC) and trichloroacetic acid (TCA), as well as the volatile metabolites of trichloroethylene, i.e. dichloroacetyl chloride (DCAC), dichloroacetic acid (DCA), and 2,2,2-trichloroethanol (TCE). In the ...
Gichner T - - 1994
The m-, o- and p-isomers of aminobenzoic acid (ABA) repressed the mutagenicity of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) in Salmonella typhimurium TA100. Their antimutagenic potency was in the order of o-ABA > m-ABA > p-ABA. The mechanism of this antimutagenicity is ascribed mainly to the decomposition of MNNG induced by the aminobenzoic acid ...
Jideani V A - - 1994
The fate of sorbic acid in pearl millet and sorghum doughs on cooking and storage is reported. A solution of sorbic acid added to the cereal flours gave a dough, which was cooked to give the product 'fura'. A significant amount (40%) of the sorbic acid was not recovered from ...
Natelson S - - 1994
This report confirms the potent mutagenic and antitumor activity of L-homoserine hydroxamic acid in both in vitro and in vivo test systems. Its mutagenic potential is evident in the developing tadpoles of Xenopus laevis eggs exposed to the compound. Cytotoxic effects are demonstrated against human leukemia and melanoma cell lines ...
Romert L - - 1994
The aim of this study was to screen for potential agents affecting the mutagenicity of tobacco products. The influence of a number of compounds which have been suggested to be antimutagenic some of which are present in tobacco products, was investigated on the mutagenicity of a cigarette smoke condensate (CSC) ...
Lee H - - 1994
Bacterial frameshift mutagens have been found in boiled pork juice. The mutagenic compounds of boiled pork juice were purified and analyzed by HPLC. The mutagenic fractions corresponding to the peaks of the standard mutagens 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), and 2-amino-3,4-dimethylimidazo[4,5-f]quinoline (MeIQ) were confirmed by comparison of UV and mass spectra. ...
Mangold J B - - 1994
The mutagenic effects of azide (N3-) anion in bacterial test systems require the formation of the novel mutagenic metabolite, 3-azido-L-alanine (AZAL). Although the mechanism of AZAL-induced mutagenicity is unknown, subsequent bioactivation of this metabolite appears likely. Earlier studies have shown that other azide-containing amino acids are mutagenic as well. In ...
Young H S - - 1994
An attempt was made to isolate the active component of Eriobotrya japonica, which inhibits aflatoxin B1-induced mutagenicity in the Salmonella assay system. The number of revertants per plate was significantly decreased when a MeOH extract of Eriobotrya japonica was added to the assay system using Salmonella typhimurium TA100 or TA98. ...
Barch D H - - 1994
The anticarcinogen ellagic acid significantly reduces the incidence of polycyclic aromatic hydrocarbon induced carcinomas, in association with significant reductions in benzo[a]pyrene hydroxylase activity and CO reducible hepatic cytochrome P450. This suggested that ellagic acid reduced hepatic concentrations of CYP1A1, but these changes occurred without any alteration in CYP1A1 mRNA or ...
Surh Y J - - 1994
6-Sulfooxymethylbenzo[a]pyrene has recently been shown to be a strong hepatocarcinogen in infant male B6C3F1 mice (Y.-J.Surh et al., Biochem. Biophys. Res. Commun., 172, 85-91, 1990) and appears to be an ultimate carcinogenic metabolite of 6-hydroxymethylbenzo[a]pyrene and possibly of benzo[a]pyrene. It produced high levels of aralkyl DNA adducts in the livers ...
Rogers C G - - 1994
Okadaic acid, a specific phosphatase inhibitor and non-phorbol ester type tumour promoter, was examined for cytotoxic and genotoxic properties in a hepatocyte-mediated assay with V79 Chinese hamster lung fibroblasts. Genetic endpoints measured were: mutation to 6-thioguanine resistance at the hgprt gene locus and induction of sister chromatid exchange (SCE). The ...
Nakayama T - - 1994
A variety of synthetic and dietary polyphenols protect mammalian and bacterial cells from cytotoxicity induced by hydroperoxides, especially hydrogen peroxide (H2O2). Cytotoxicity of H2O2 on Chinese hamster V79 cells was assessed with a colony formation assay. Cytotoxicity and mutagenicity of H2O2 on Salmonella TA104 were assessed with the Ames test. ...
Balansky R - - 1994
A series of naturally occurring compounds were tested for the ability to modulate the mutagenicity induced by cigarette smoke (CS), cigarette smoke condensate (CSC) and benzo[a]pyrene (BP) in the Salmonella/microsome mutagenicity assay and the micronucleus test in mouse bone marrow. Sodium selenite, retinol acetate and alpha-tocopherol significantly decreased the mutagenic ...
el Gazzar R M - - 1994
Electrophilic compounds are widely used in industry. Plastic and dyeing industries are foremost examples of sites where workers are exposed to electrophilic compounds. Besides their immediate effect on different body systems, electrophilic compounds include most mutagenic and carcinogenic substances. The present study was carried out to elucidate the possibility of ...
Knize M G - - 1994
To investigate the formation of aromatic amine-like mutagenic activity in cooked grain foods, amino acids were heated alone or in binary combinations at either 150 or 210 degrees C. About half of the binary mixtures of arginine heated with other amino acids produced potent mutagenic responses in the Ames/Salmonella assay, ...
Sato T - - 1994
The ability of phthalic acid, phthalic acid anhydride, and various phthalate esters to enhance the mutagenicity of many amino acid pyrolysates was observed with the Ames test (Salmonella typhimurium TA98), but not the SOS Chromotest. Phthalate enhancement of the mutagenicity of 4-nitroquinoline-1-oxide, 2-nitrofluorene, and benzo[a]pyrene was not observed with either ...
Aidoo A - - 1994
Recent reports suggest that ascorbic acid (vitamin C) inhibits tumorigenesis as well as exerts a protective effect against mutagenesis in vitro; however, there is no information on its ability to affect gene mutations induced in vivo. In this study, we have investigated the antimutagenic effects of ascorbic acid on the ...
Chang R L - - 1994
trans,trans-Muconaldehyde (MUC), a six-carbon-diene-dialdehyde, is a microsomal, hematotoxic ring-opened metabolite of benzene. MUC is metabolized to a variety of compounds which are formed by oxidation and/or reduction of the aldehyde group(s). In the present studies, MUC and its metabolites were examined for mutagenic activity at the hypoxanthine guanine phosphoribosyltransferase (HGPRT) ...
Zani F - - 1993
The effects of Glycyrrhiza glabra L. extract, glycyrrhizinic acid, 18 alpha- and 18 beta-glycyrrhetinic acids on the mutagenicity of the ethyl methanesulfonate, N-methyl-N'-nitro-N-nitrosoguanidine, and ribose-lysine Maillard model systems were investigated by using the Salmonella/microsome reversion assay. The protocol used allowed us to detect desmutagenic and antimutagenic activity and to avoid ...
Guo X - - 1993
When the time course of the hydrolysis of identical solutions of p-nitrophenyl N-acetyl-alpha-D-neuraminide by Salmonella typhimurium neuraminidase is monitored by u.v. and by its optical rotation, the rotation change is synchronous with, or even marginally in advance of, the absorbance change. In experiments under the same conditions with influenza-virus neuraminidase, ...
De Flora S - - 1993
Specimens of rainbow trout (Oncorhynchus mykiss) were either kept in an aquarium under laboratory conditions or caged in the River Po (Northern Italy), upstream or downstream the confluence with the River Lambro, a small yet heavily polluted tributary. Genotoxicity biomarkers, evaluating the internal dose or early biological effects, were monitored ...
Hume M E - - 1993
Newly hatched broiler chicks were provided a corn/soybean meal-based ration treated with propionic acid at 30 mumol/g of feed ration. At 3 days of age, the chicks were challenged orally with 10(4) Salmonella typhimurium. Crop contents from 4-day-old chicks that were provided dietary propionic acid contained significantly higher concentrations of ...
Pistelli L - - 1993
Two aristolochic acids [2 and 3] and a flavonol glycoside 1 have been isolated from Aristolochia rigida (Aristolochiaceae). Aristolochic acid IV [2], the most abundant constituent, has shown a weak direct mutagenic activity in the Ames test: this action seems to be inhibited, at least in part, by metabolic reactions.
Larsen G J - - 1993
Laboratory mice were inoculated with a nalidixic acid and novobiocin-resistant strain of Salmonella typhimurium. Contaminated fecal pellets were harvested 2 days postinoculation. Each half of a fecal pellet was found to contain equal numbers of Salmonella on a per weight basis. When separate halves were placed into a poultry feed, ...
Ewald G - - 1993
The capacity of stearic, monochlorostearic, dichlorostearic and oleic acids to cause membrane damage was measured as their ability to induce leakage of adenosine triphosphate (ATP) from mammalian tumour cells in vitro. Chlorinated stearic acids, and oleic acid, caused ATP leakage at lower concentrations than normal stearic acid. The membrane disturbing ...
Holloway T C - - 1993
Nitrated derivatives of the aza-arenes carbazole and 2-hydroxycarbazole were synthesized and tested for mutagenicity in the Ames plate-incorporation assay. 3,6-Dinitrocarbazole was the most mutagenic towards Salmonella typhimurium strain TA98 (> 100 revertants/micrograms, 25 revertants/nmol, with or without S9) followed by 2-hydroxy-1,3,6-trinitrocarbazole (24 revertants/micrograms, 7 revertants/nmol without S9) and 2-hydroxy-3-nitrocarbazole (27 ...
Castonguay A - - 1993
The aims of this study were to define the cumulative exposure of Canadian smokers to NNK and to characterize the efficacy of ellagic acid to inhibit lung tumorigenesis induced by NNK. The sales-weighted average of NNK deliveries from Canadian cigarettes was 73.2 ng/cigarette. NNK deliveries were highly correlated to declared ...
Srám R J - - 1993
Recent data from deep uranium mines in Czechoslovakia indicated that in addition to radon daughter products, miners are also exposed to chemical mutagens. Mycotoxins were identified as a possible source of mutagenicity present in the mines. Various methods of biomonitoring were used to examine three groups of miners from different ...
Cozzi R - - 1993
Humic acids are natural components of organic matter widespread in the environment. In spite of the incomplete knowledge about their composition, increasing interest in humic acid activity is justified by their ubiquity. Four different humic acids have been tested in Chinese hamster ovary cells in vitro, both alone and in ...
Trizna Z - - 1993
The protective effects of ascorbic acid (AA), n-acetyl-l-cysteine (NAC), alpha-tocopherol acid (ATA), alpha-tocopherol-acid succinate (TAS), and 13-cis-retinoic acid (CRA) on mutagen-induced chromosomal breakage were studied. Mutagen-sensitivity was determined by the bleomycin assay in human lymphoblastoid cell lines (LCLs) and cultures of peripheral blood lymphocytes (PBLs) from head and neck cancer ...
Götzl E - - 1993
Aristolochic acid I and II, two naturally occurring nitroaromatics, were studied for their mutagenicity in Salmonella typhimurium tester strains YG1020, 1021, 1024, 1025, 1026 and 1029 without exogenous metabolic activation. These strains contain multicopy plasmids which carry the genes for the classical bacterial nitroreductase or O-acetyltransferase. The strains TA98, TA100 ...
LaLonde R T - - 1993
A difference in biological response to enantiomers is not an uncommon observation and is, therefore, to be expected in various manifestations of genotoxicity. The bacterial mutagen mucochloric acid (2,3-dichloro-5-hydroxy-2(5H)-furanone) has one chiral center, at C-5, but this mutagen exists in racemic form because of the facile stereoisomerization occurring by the ...
Kumar R - - 1993
Caffeine on alkaline hydrolysis produces caffeidine [1-methyl-4-(methylamino)-5-(N-methylcarbamoyl)imidazole] and caffeidine acid [N-[4-(5-carboxy-1-methylimidazolyl)]-N,N'-dimethylurea]. We now report the synthesis and chemical characterization of mononitrosocaffeidine [1-methyl-4-(N-methyl-N-nitrosoamino)-5-(N-methylcarbamoyl)i midazole], dinitroso-caffeidine [1-methyl-4-(N-methyl-N-nitrosoamino)-5-(N-methyl-N-nitrosocarb amo yl) imidazole], and mononitrosamidocaffeidine [1-methyl-4-(methylamino)-5-(N-methyl-N-nitrosocarbamoyl)-Imidazole] based on spectral analysis. The characterization of nitrosated byproducts obtained during the synthesis of these compounds is also presented. ...
Zawadzka M - - 1993
Genotoxic effect and hepatic microsomal monooxygenase activities were assessed in mice treated with Acid Green 16 (single i.p. injection at dose 75 mg/kg) superimposed on prolonged ethanol consumption (10% solution in drinking water for 2-4 months). Treatment of mice with Acid Green 16 led to an increased frequency of micronucleated ...
Kuo M L - - 1992
Four naturally occurring compounds, indole-3-carbinol (I3C), apigenin (Api), ellagic acid (EA) and tannic acid (TA), were tested for their inhibitory effects against 1-nitropyrene- (1-NP) or 1,6-dinitropyrene (1,6-DNP)-induced genotoxicity in Salmonella tester strains and Chinese hamster ovary (CHO) cells. Api and TA strongly inhibited the bacterial mutagenesis induced by nitropyrenes, while ...
Ho T A - - 1992
Hepatic microsomal fractions (microsomes) were prepared from male Sprague-Dawley rats. The effect of arachidonic acid on the conversion of the heterocyclic aromatic amine 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) to its genotoxic metabolites was investigated using a modified bacterial mutation assay (indicator: Salmonella typhimurium TA98). Arachidonic acid inhibited the mutagenicity of IQ without effect ...
Kerr S W - - 1992
Inhibitory factor (IF), an extract of the bovine retractor penis muscle, when treated with acid, becomes a vasodilator with properties similar to endothelium-derived relaxing factor (EDRF). EDRF has been proposed to be nitric oxide (NO), long known to be a potent vasodilator. Recently, biologically active IF was proposed to be ...
Hô T A - - 1992
The effect of arachidonic acid, eicosapentaenoic acid and docosahexaenoic acid on the conversion of the heterocyclic amine 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) to its genotoxic metabolites was investigated using a modified bacterial mutation assay. The assay used Salmonella typhimurium TA98 as an indicator of the mutagenicity and hepatic post-mitochondrial fractions (S-9) from male ...
Loprieno G - - 1992
The potential genotoxic activity of carminic acid (CAS no. 1260-17-9; EINECS no. 215-023-3; C.I. no. 75410), a component of natural red colouring products (cochineal: CAS no. 1343-78-8; EINECS no. 215-680-6; C.I. no. 75470), used in food, cosmetics and drugs, has been evaluated by means of a series of short-term tests ...
LaLonde R T - - 1992
The Salmonella typhimurium (TA100) mutagenic compound, mucochloric acid [3,4-dichloro-5-hydroxy-2(5H)-furanone (MCA)], was inactivated by in vitro N-acetylcysteine (NAC). The reaction of MCA with NAC at pH7 was second order and gave products 4, 5, and 6a that resulted from the displacement of chlorine from C-3 or C-4 of MCA. The sodium ...
Frank A A - - 1992
Ellagic acid is a naturally occurring plant phenol that has demonstrated anticarcinogenic and antimutagenic activity in several test systems. Given the common proposed etiopathogenic processes of mutagenesis, carcinogenesis, and teratogenesis induced by genotoxic chemicals, the present study was initiated to determine whether ellagic acid would protect rat embryos in culture ...
Kato T - - 1992
Protein and its components in high concentrations similar to those found in the digestive tract effectively scavenged nitrite and thus inhibited the formation of mutagens from nitrite. Various amino acids at 100 mM, bovine serum albumin (BSA) and trypsinized casein at 100 mg/ml effectively decreased the nitrite level of 50 ...
Thompson Morrow - - 1992
Formic acid occurs in a variety of plants and fruits, mammalian tissues, and insect venoms. It is used industrially in preparing a variety of drugs, dyes, and chemicals; as a decalcifier; and in leather tanning. Formic acid also is an environmental contaminant of air and water and has been identified ...
Tan E L - - 1992
TNT was mutagenic for Salmonella typhimurium without the need of a rat liver metabolic activation system (S9). The mutagenic potency of TNT decreased in proportion to the number of nitro groups that were reduced to the amino form. The presence of a nitro group on the 4 position of the ...
Kako Y - - 1992
Nitrite treatment enhances the direct-acting mutagenicity of various foodstuffs (e.g., chicken, bloater, the soybean flour 'kinako', and Ban-Ban-Chi sauce) on Salmonella typhimurium TA100. p-Aminobenzoic acid (PABA) and glutathione (GSH) reduced this mutagenicity; on the other hand, thioproline (TPRO) increased it. PABA seemed more effective than TPRO in scavenging nitrite ion. ...
Leyer G J - - 1992
Salmonella typhimurium was adapted to acid by exposure to hydrochloric acid at pH 5.8 for one to two doublings. Acid-adapted cells had increased resistance to inactivation by organic acids commonly present in cheese, including lactic, propionic, and acetic acids. Recovery of cells during the treatment with organic acids was increased ...
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