Tulipa gesneriana bulb extracts activate promutagenic 7,12-dimethylbenz[a]anthracene in the salmonella/ames assay.

Crude extracts from Tulipa gesneriana bulbs have been tested for their ability to activate 7,12-dimethylbenz[a]anthracene (DMBA) in the Salmonella mutagenicity assay. Bacteria of strain TA98 were incubated for 30 min at 37 degrees C with the mixture of the promutagen and bulb extracts prior to plating. The frequency of his+ revertants increased in relation to both the promutagenic dose and the amount of bulb extract in the mixture, and under optimal conditions, was more than 50 times higher than the value found after the action of the promutagen alone. Addition of NADP and glucose 6-phosphate to the incubation mixture did not seem to be obligatory.