Abstract

Obtaining bioactive metabolites from endophytic microorganisms has become increasingly more interesting in the last few decades, since endophytes are known for their biotechnological potential. However, studies involving endophytic microbiota from tropical hosts are still scarce. In this study, the production of bioactive metabolites from endophytic fungi isolated from Amazonian plants were evaluated. Two fungi (Talaromyces sp. F15 and Aspergillus sp. F18) isolated from Myrcia guianensis (Myrtaceae) and one (Penicillium sp. F3) isolated from Euterpe precatoria (Arecaceae) were analysed. The fungi were cultivated in liquid medium and their metabolites were tested for antimicrobial, antioxidant and cytotoxic activity. Amylase, cellulase and lipase production, as well as biosurfactant production, were also evaluated. The metabolites of Aspergillus sp. F18 showed 69.4% antioxidant activity against DPPH free-radical molecules and cytotoxic activity against A. salina. Penicillium sp. F3 showed cytotoxic activity and stood out as the best amylase producer (31 U/ml). Talaromyces sp. F15 was the best lipase producer (4.5 U/ml) and the best biosurfactant source, with 33.3% emulsification index. These Amazonian host-associated fungi showed biotechnological potential, which are believed should be further investigated in order to elucidate the chemical structure of the metabolites responsible for the activities described here, as well as optimize their production.

Key words: Enzymes, lipase, cellulase, amylase, biosurfactant, antioxidant, antimicrobial, cytotoxic.