Abstract
Aqueous extracts of some medicinal plants used by Purépecha (a Mexican ethnic group) for the treatment of gastrointestinal diseases were tested against Escherichia coli, Salmonella typhi and Shigella boydii. Antimicrobial activity was detected in extracts from Lepechinia caulescens (Ort.) Epl., Lepidium virginicum L. and Tanacelum parthenium (L.) Sch. Bip.