Prospection of bacterial endophytes isolated from Baru (Dipteryx alata Vog.) as a potential source of bioactive compounds

摘要

The term “endophytes” includes a suite of microorganisms that grow intra and/or intercelullarly in the tissues of higher plants without causing over symptoms on the plants in which they live. These microorganisms represents a potential source of novel natural products for medicinal, agricultural and industrial uses, such as antibiotics, anticancer agents, biological control agents, and other bioactive compounds. The aim of the present work was to investigate the biotechnological potential of bacterial endophytes isolated from Baru (Dipteryx alata Vog.). Accordingly, the antimicrobial activity, the enzymatic profile and the biotransformation of α-pinene in aroma compounds were evaluated. A total of 17 bacteria strains were isolated from Baru and identified in the present work. Screening of the antimicrobial activity of endophytic extracts revealed a considerable activity against the pathogenic cultures tested. Most of the extracts inhibited the growth of Candida albicans, Escherichia coli and Sthaphylococcus aureus. Furthermore, it was observed that the vast majority of bacteria showed a high level of protease activity, whereas the lipase and amylase profile were detected in most isolates but with less intensity. The preliminary results obtained from the biotransformation process showed that 2 bacterial strains bioconverted α-pinene into verbenol (85% similarity in MS results). The bioconversion occurred based on the biochemical hydroxylation of α-pinene, and this reaction was reported in some articles. This paper represents the use of bacterial endophytics isolated from the Cerrado brazilian biome and demonstrates a partial use of these microorganisms in biotechnological processes and their potential as source of bioactive compounds.