Atividade antioxidante e antimicrobiana de extratos vegetais de folhas de espécies nativas de Myrtaceae

Abstract

The Myrtaceae family presents a diversity of native fruit species with the potential to be explored. The fruits have been the main economic return exploited, but the potential of the leaves still needs to be elucidated to make the source material of income to the producers and alternative for pharmaceutical and alimentary industries. The objective of the work was to evaluate the antioxidant potential of ethanolic leaves extracts of 11 native Myrtaceae species collected i n different season s and select the best ones to test the antimicrobial activity on Staphylococcus aureus, Escherichia coli, Salmonella enterica subsp. enterica and Pseudomonas aeruginosa . The experiment was carried out at the Universidade Tecnológica Federal do Paraná Câm pus Dois Vizinhos with species from the Native Fruit Collection. The experimental design was completely randomized, in factorial 11 x 4 (species x collection period), with three replications, considering each plant as an experimental unit. From the ethanol ic extract of the collected material, analyzes of total phenolic compounds, antioxidant activity by the ABTS, DPPH and FRAP methods were performed. Four extracts were selected to perform antimicrobial activity and quantif ication of phenolic compounds by hi gh performance liquid chromatography (HPLC). For total phenolic compounds the extracts of araçazeiros (red and yellow), the uvaieira and the hybrid jabuticabeira stood out over the others, being these selected for analysi s of antimicrobial activity. The ex tracts tested had antimicrobial potential on E. coli, S. aureus , and S. enterica. Catechin predominated among the compounds quantified in extracts of red and yellow and hybrid jabuticabeira. In the extract of uvaieira the ferulic acid was found in greater quantity. Both compounds are antioxidants and antimicrobials.