Antimicrobial and Cytotoxic Properties of Extracts from Plants Traditionally Used in North-East Brazil

The north-eastern region of Brazil is home to communities of diverse ethnic origins that still depend significantly on folk medicine, with emphasis on plant extracts. The present work aims at investigating medicinal plants used in the traditional medicine of north-eastern Brazil with an assessment of the antimicrobial profile of their extracts. The antimicrobial activity of 12 extracts from 11 plant species from eight higher plant families traditionally used was evaluated against three human pathogens (Staphylococcus aureus, Escherichia coli, Streptococcus pneumoniae) using the Agar Disk Diffusion and Broth Microdilution assays. The cytotoxic effects were evaluated on human keratinocytes. A hydroalcoholic extract from Anadenanthera colubrina presented the most promising in vitro antimicrobial activity against S.aureus associated with low cytotoxicity towards human keratinocytes. The information gathered in the present study represents a starting point for further research aiming at providing scientific evidence to the empirical usage of medicinal plants in traditional practices.