Abstract
Water extracts of 41 commercial crude drugs were subjected to screening studies for mutagenicity by means of the reversion assay with Ames'strain TA 98 and TA 100 of Salmonella typhimurium. Ten of the water extracts were found to be positive in the Ames test. In general, these observed mutagenicity was, however, quite weak. Among them we attempted to isolate a major mutagenic component from Sophorae flos which was markedly active, and was regarded as quercetin.
