Abstract

This study describes the bio-guided isolation of compounds with antimicrobial activity fromRapanea ferruginea, as well as the cytotoxic and genotoxic potential. The extracts of stem bark, branches, leaves, fruits and the compounds were evaluated in vitro against bacteria and yeast strains, and were submitted to phytochemical screening and bioautography to guide the isolation of active compounds. The toxic potential was evaluated by brine shrimp test (BST) and murine fibroblast L929 cells, and genotoxicity was evaluated using the yeastSaccharomyces cerevisiae (haploid wild-type). Through bioactivity-directed fractionation, the stem bark extract was chromatographed to yield the antimicrobial compounds identified as myrsinoic acids A and B (MAA, MAB) that presented significant antibacterial activity against Staphylococcus aureus and Bacillus subtilis. It was verified that the compounds MAA and MAB presented moderate toxic potential on BST. However, these compounds did not present citotoxic activity on L929 fibroblasts cells and also were not mutagenic in S. cerevisiae. In conclusion, compounds from R. ferruginea might have great potential as antimicrobial agents. This study showed the antimicrobial activity of stem bark and fruits ofR. ferruginea presented activity against Gram-positive bacteria and this effect is associated with the major percentage of MAA and MAB.

Key words: Rapanea ferruginea, antimicrobial, cytotoxicity, genotoxicity, medicinal plant.