A Gram-positive, endospore-forming, rod-shaped bacterium, strain PD-A10 T , was isolated from salted crab (poo-khem) in Thailand and subjected to a taxonomic study. Phenotypic and chemotaxonomic characteristics, including phylogenetic analyses, showed that the novel strain was a member of the genus Bacillus. The novel strain grew in medium with 0-14 % (w/v) NaCl, at 4-55 6C and at pH 4.5-9. The predominant quinone was a menaquinone with seven isoprene units (MK-7). The major fatty acids were anteiso-

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Black glutinous rice (Oryza sativa var. glutinosa) and Hom Nil rice (Oryza sativa) are colored rice varieties with antioxidant properties, popular among health conscious consumers. We studied the antimutagenicity of raw, cooked and fermented samples against two direct mutagens-nitrite-treated 1-aminopyrene and nitrite treated chicken essence-in an Ames assay using Salmonella typhimurium strains TA 98 and TA 100. The extract of each sample with acid alcohol reduced the mutagenicity of both mutagens. In addition, the antimutagenicity of the extracts from the samples made of black glutinous rice was higher than that of the extracts from samples made of Hom Nil rice. The protective effects of these rice varieties might be due to the presence of some phytochemicals, including anthocyanins, which are the main antioxidant. The selected rice varieties might be appropriate for p

This study evaluated the possibility that extracts from some edible mushrooms (button, shiitake, oyster and abalone) could modulate the formation of the mutagen precursor during extended period cooking of beef and the direct mutagen produced from interaction between nitrite and beef concentrate. The concentrates from beef boiled with the mushroom samples did not show the mutagenicity when tested with the Ames test using Salmonella typhimurium strains TA98 and TA100 in the absence of metabolic activation. After treated with nitrite, they exhibited the mutagenicity towards both strains. The results showed that the addition of mushroom extracts to the beef concentrate before treated with nitrite did not reduce the mutagenicity. However, the actual mutagenicity of the mixtures of mushroom extracts and beef concentrates treated with nitrite was less than the calculated value. Exceptions were found in button and oyster mushroom extracts on TA98. Thus, it was indicated that some mutagen precursors presented in all concentrates could interact with nitrite and addition of these mushrooms could not reduce the formation of the mutagen precursors.