Antimutagenicity of 3 - allyl - 5 - substituted derived from ally 1 isothiocyanate and Salmonella assay 2 - thiohydantoins amino acids in

metabolic activation system (S9 mix) and that against 4-NQO was earried out on S.t)iphimurium [£AIOO in the absence of S9 mix. wnen AI'H-amino acids except for that prepared from AITC and aspanic acid were simultaneously treated with the bacterial strain and IQ, an inhibition of IQ mutagenicity was observed. Also, all ATH-amino acids showed a suppressive effect on 4-NQO mutagenicity when the bacterial strain was incubated in the presence of both 4-NQO and M'H-amino acids. In contrast, little antimutagenic effect was observed when iYI"H-amino acids were added to the bacterial strains which has been pretreated with a mixture of IQ and S9 mix or only 4-NQO. 'Ihese results