Salmonella typhimurium, mutagenicity toward

Salmonella typhimurium. Although most nitro PAHs are direct-acting mutagens in Salmonella typhimurium, these compounds must be metabolized to bind covalently to DNA (71,92,112). S. typhimurium contains a family of nitroreductases which are capable of reducing nitro PAHs, and strains which are deficient in these enzymes generally show decreased sensitivity toward nitro PAH-induced mutations (27,92,113-114). These observations suggest that reduced metabolic intermediates may be the critical reactive electrophiles. 

Kensese, S.M. Smith, L.L. (1989) Hydrogen peroxide mutagenicity towards Salmonella typhimurium. Teratog. Carcinog. Mutag., 9, 211-218... 

Liriodenine was found to be the mutagenic principle in a methanol extract of the root, root stalk, and stem of Sinomenium acutum (Menispermaceae). The alkaloid exhibited potent mutagenic activity towards Salmonella typhimurium strains TA98 and TA100 in the presence of liver homogenate (S9 mix)(10.9 and 90.7 revertants/nmol, respectively), and accounted for about 40% of the mutagenicity of the total methanol extract. The mutagenic potency of liriodenine is comparable to that of benzo[a]pyrene [295]. 

Wilpart M, Mainguet P, Maskens A, et al. 1983. Mutagenicity of 1,2-dimethylhydrazine towards Salmonella typhimurium, co-mutagenic effect of secondary biliary acids. Carcinogenesis 1 45-48. 

Mutagenic Activities of iV-Heterocyclic Amines Towards Salmonella typhimurium ... 

In another comparison of mutagenicities toward Salmonella typhimurium TA 98, Nagao et al. (2667c) calculated the B[fl]P equivalency of extracts of charred fish and meat. Their data, with additions [charred food weight in ounces, cigarette equivalents based on B[a]P], are shown in Table XVII.F-5. 

Calle LM, Sullivan PD 1982 Screening of antioxidants and other compounds for antimutagenic properties towards benzo(a)pyrene-induced mutagenicity in strain Ta98 of Salmonella typhimurium. Mutat Res 101 99-114... 

Bisphenol A (BPA), an endociine-disrupting chemical, is commonly found in food packaging and can coatings. Nitrate is found in vegetables, fish, and in potable water as a pollutant. Bisphenol A alone did not exhibit mutagenicity toward Salmonella typhimurium strains TA 98 and TA 100 after incubation at pH 3.0 to simulate human stomach conditions. When nitrate was added to bisphenol A, however, the mixture showed strong mutagenic activity [107]. 

Ames assays of methyl, ethyl, w-propyl, and -butyl hydroperoxides (see Chapter 23) have shown some tendency toward mutagenicity on select strains of Salmonella typhimurium, although any conclusions drawn from such studies on human health... 

Even more complicated and confusing studies are being reported. For example, Yoshida and Matsumoto treated pyrolysates of proteins with nitrite under acidic conditions and determined the resulting mutagenic activity in Salmonella tester strains. In these tests, casein pyrolysate, an extract of roasted chicken meat and some aromatic amines (viz. 3-amino-l,4-dimethyl-5H-pyrido[4,3-b]indole and 2-aminobenzo(h)quinoline), showed appreciable decreases in mutagenic activity toward S. typhimurium TA98. 

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