Blackberry extracts inhibit UV-induced mutagenesis in Salmonella typhimurium TA100

The development of metastatic cancer involves a series of mutagenic events. Compounds in blackberries effectively block mutagenesis by metabolically activated carcinogens and can serve as effective anticancer agents. We have compared the effects of 8 different varieties of blackberry on UV-C–induced mutagenesis in Salmonella typhimurium TA100. The 8 varieties were cultivated under identical conditions and harvested as ripe berries. Two varieties had no effect on UV-C–induced mutagenesis. Two showed significant suppression of mutagenesis. The other 4 had intermediate effects. Berry extracts were added only after irradiation of the cells was complete. The results imply that some varieties of blackberries contain substances that might inhibit error-prone DNA repair.