Endophytic compounds from Nigerian plants is of significant interest in the search for drug compounds possibly due to their potentials to contribute new compounds with biological properties in the fight against drug resistance pathogens. Consequently, this study was embarked upon to investigate the bioactivities of secondary metabolites of endophytic Aspergillus sp. isolated from the leaves of Mangifera indica. Fresh leaves of M. indica were prepared for fungal isolation, identification, fermentation, and secondary metabolites extraction. The crude extract was subjected to HPLC analysis. The HPLC analysis revealed the presence of two bioactive compounds: p-Hydroxylbenzoic acid, and Protocatechuic acid. The extract was tested for antimicrobial, antioxidant, cytotoxic and antiviral properties. The extract exhibited antibacterial activity against Pseudomonas aeruginosa and Escherichia coli producing IZD of 4 mm respectively at 1mg/mL. The extract produced an interesting antioxidant activity in the 1,1-diphenyl-2-picryl-hydrazyl (DPPH) assay with 86.7% activity at a concentration of 0.5 mg/mL. At 0.01mg/mL, the Aspergillus sp. extract showed 85.3% cytotoxic activity against L5178Y mouse lymphoma cells and showed 96.5% Â±0.173 HIV-1 reverse transcriptase inhibition activity at 0.25mg/mL. This study shows that endophyte of M. indica (Aspergillus sp.) produces bioactive compounds that could be useful as novel drug molecules in the fight against drug resistance.
Keywords: Endophytic fungi, Aspergillus sp., Mangifera indica, Secondary metabolites, Reverse transcriptase