Mutagenicity of medicinal plant extracts in Salmonella/microsome assay

Aqueous extracts of medicinal plants used in south Brazilian folk medicine (Myrciaria tenella, Smilax campestris, Tripodanthus acutifolius and Cassia corymbosa) were screened for the presence of mutagenic activity in the Salmonella/microsome assay. Signs of an increased mutagenic induction below revertant rates, which is two times the spontaneous yields, were detected for all extracts. The extracts of C. corymbosa showed signs of mutagenic activity in the following strains: TA100 with and without metabolization and TA98 after metabolization. These mutagenic signs were observed in the M. tenella extracts without metabolization. S. campestris and T. acutifolius infusions also showed signs indicative of direct mutagenic activity in the TA98 strain. The positive results may be related to the presence of flavonoids, tannins and anthraquinones in the extracts.