MUTAGENICITY AND ANTIMUTAGENICITY OF EXTRACTS OF 3 SPICES AND A MEDICINAL PLANT IN THAILAND

Three kinds of spices (caraway, coriander and black pepper seeds) and a medicinal plant called 'tong tak' in Thai (Baliospermum axillar, a s pecies of the spurge family) were fractionated into hot water, methano l and hexane extracts. These extracts were not mutagenic for Salmonell a typhimurium strains TA98 and TA100 by the Ames assay. However, when the extracts were treated with nitrite, samples of the water and metha nol extracts were mutagenic for strain TA100 without metabolic activat ion. The mutagenicity of the nitrite-treated methanol and hot water ex tracts of black pepper was highest (8380 and 22,200 His(+) per 0.1 g o f spice powder, respectively), and that of the nitrite-treated hot wat er extracts of caraway and tong tak was moderate. The hot water extrac ts were examined for their antimutagenic activity against mutagenicity induced by various carcinogens by the Ames assay, using the preincuba tion technique. The tested samples (equivalent to 1-2 mg of spice powd er) reduced the mutagenicity induced by 2.7 nmole (397 ng) of N-methyl -N'-nitro-N-nitrosoguanidine by more than 84%, and that induced by dim ethylnitrosamine (1.48 mg) or ICR-170 (10 ng) by 30-60%. However, they did not inhibit the mutagenic activity of l-nitropyrene, 3-nitrofluor anthene, AF-2, methyl methanesulfonate, N-ethyl-N'-nitro-N-nitrosoguan idine, 2-aminoanthracene, 2-acetylaminofluorene, benzo[a]pyrene or IQ.