Evaluation of the antioxidant activity, antimicrobial effect and acute toxicity from leaves of Allophylus edulis (A. St.-Hil., A. Juss. Cambess .) Hieron. ex Niederl

Allophylus edulis is a Brazilian plant  commonly used in the mid-west region of Brazil for treatment of disorders  related to oxidative stress such as diabetes, inflammation, hypertension and digestive diseases. The aims of the present study were to quantify flavonoids and phenolic compounds, evaluate the antioxidant activity, antimicrobial effect and acute toxicity of leaves of A. edulis. Ethanolic (EEAE) and aqueous (AEAE) extracts of A. edulis were prepared. The antioxidant activity was determined by 2.2-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging,  lipid peroxidation and oxidative hemolysis induced by 2.2'-azobis (2-amidinopropane). The antimicrobial assays of diffusion on solid media and broth microdilution were performed against Staphylococcus aureus, Escherichia coli and Candida albicans. The acute toxicity was assessed in Wistar rats treated with doses of 2 and 5 g/kg of body weight. The EEAE presented higher concentrations of flavonoids and phenolic compounds, and higher activity of scavenge DPPH free radicals. In addition, it was more effective against S. aureus compared to AEAE. The extracts were unsuccessful against E. coli and C. albicans. The EEAE prevented the lipid peroxidation in human erythrocytes and inhibited oxidative hemolysis in all  the concentrations assessed. During the evaluation of acute toxicity, the dose of 5 g/kg of body weight increased hepatic mass. Together, these results demonstrated that the EEAE of leaves of A. edulis is more effective than the AEAE, showing antioxidant activity and antimicrobial effect against S. aureus, as well as low toxicity. Key words: Cocum, native Brazilian plant, lipid peroxidation, DPPH, AAPH, TBARS, malondialdehyde, Sapindaceae.