In vitro assessment of antimicrobial and anti-inflammatory potential of endophytic fungal metabolites extracts

Abstract

Endophytes are endosymbiotic microorganisms that act as reservoir of novel bioactive secondary metabolites with antimicrobial, cytotoxic and anti-cancer activities. In the present study, the extracts of 26 different endophytic fungal strains were screened for their antimicrobial and anti-inflammatory activities. The results showed a wide variety of antimicrobial activities against 12 target microorganisms including three Gram (+) bacteria, three Gram (-) bacteria, 3 yeasts, 2 dermatophytic fungi and one keratinophilic fungus. Four fungal extracts ( Aspergillus versicolor , A. awamori , A. niger and Penicillium funiculosum ) displayed a broader antibacterial spectrum and inhibited the growth of all Gram (+) and Gram (-) bacterial species. The extracts of 8 endophytic fungi inhibited the growth of the two tested dermatophytic strains ( Trichophyton mentagrophytes and T. rubrum ). Only eight fungal extracts have an inhibition activity against the keratinophilic fungal strain ( Chrysosporium tropicum ). The anti-inflammatory assay showed that the extracts of Emericella nidulans , Pleospora tarda and Penicillium funiculosum had good activities in inhibition of protein denaturation reached to 83%, 82.5% and 81.4%, respectively. Also, Emericella nidulans and Pleospora tarda recorded the maximum inhibition effect on bovine serum albumin denaturation reached to 95% and 90.7%, respectively. On the other side, Emericella nidulans showed the maximum inhibition activity (69.5%) out of all tested endophytic strains against humun red blood cells membrane stabilization assay. In conclusion some secondary metabolites of endophytic fungi have a promising potential as antimicrobial and anti-inflammatory compounds.