Antifungal Activity and the Potential Correlation with Statin-Producing Ability: An Optimized Screening Applied to Filamentous Fungi from Las Yungas Subtropical Rainforest

Abstract

Research was aimed at isolating and identifying fungal species from Las Yungas Pedemontana Forest with ability for statin production. Fungal isolates were screened by yeast growth inhibition bioassays, TLC and RP-HPLC analyses. Waring-blender-obtained fungal extracts led to higher statin yields than after disrupting with glass-beads or by freeze-thawing. Only 23 out of 230 isolates showed to be TLC(+) potential statin-producers. Eighteen extracts inhibited S. cerevisiae ATCC 32051 during yeast bioassays, while nine had the same effect on Candida utilis Pr1-2. Peaks revealed by RP-HPLC corresponded to or were closely related to known statins. Promising fungal isolates were identified as Hypocrea and Penicillium genera members. Statin concentrations were in the order of those reported for wild-type strains under non-optimal production conditions. The potential of Las Yungas filamentous fungi for statin production under laboratory conditions could be evidenced. Selected isolates may be considered as promising targets for optimizing statin production. This is the first report where investigation focuses on indigenous filamentous fungi from Las Yungas to give an insight in their hidden biotechnological potential for statin production. Optimized protocols for statin-production assessment are also proposed for future screening programs.