Fungi from Brazilian Savannah and Atlantic rainforest show high antibacterial and antifungal activity

Brazilian biodiversity is among the biggest ones in the world, providing one of the major sources for bioprospection of new bioactive molecules. This study reports the isolation of new fungal strains from Brazilian biomes, aiming the biotechnological production of antimicrobial compounds against important microorganisms in the field of foodborne diseases, and difficult healing infections. First, 169 filamentous fungi were isolated from soil samples of Savannah and Atlantic Rainforest biomes in São Paulo State. The isolates were investigated about their inhibitory effect on the growth of five microorganisms (Bacillus cereus, Staphylococcus aureus subsp. aureus, Escherichia coli, Salmonella enterica subsp. enterica and Candida albicans), by microdillution assay. Around 93.5% of the isolates showed antimicrobial activity. Among them, 13% presented high activity and were evaluated about their minimal inhibitory concentration (MIC). Results revealed extracts with low MIC (0.31mgmL−1) and with bactericidal and bacteriolytic activity. These fungi were identified as Trichoderma spp, Fusarium spp., Acremonium spp., Penicillium spp., and Paecilomyces spp. The Brazilian biomes presented themselves as interesting bioprospection spots of new sources of antimicrobial compounds, and this is the first report of antimicrobial potential of fungi from entire Atlantic rainforest or from this geographical area of Brazilian Savannah.