Antioxidant, Cytotoxic Activities and Characterization of Secondary Metabolites of Endophytic Fungus Schizophyllum Commune Isolated from Coleus Amboinicus (Lour.) Leaves

Schizophyllum commune (fam Schizophyllaceae) is an endophytic fungus isolated from a medicinal plant Coleus amboinicus (Lour.) Spreng. This study was aimed to identify metabolite profiles, characterize bioactivities (antioxidant and cytotoxic), and analyze metabolite production of the fungus due to light exposure and initial fungal culture age. Fungal cultures aged 7, 14, and 21 days old on PDA were incubated in Potato Dextrose Broth (PDB) fermentation medium for 2 weeks either in full light or dark condition. Metabolite profiles were analyzed using thin-layer chromatography (TLC) and gas chromatography-mass spectrometry (GC-MS). The 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assays were used to determine antioxidant and cytotoxic activity. The results showed that light exposure and different age of fungal cultures affected metabolite production based on TLC analysis. Phytochemical screening of ethyl acetate extract of fermentation indicated the presence of flavonoids, terpenoids, steroids, phenols, and alkaloids. There are five major compounds detected by GC-MS. Bioactive screening showed that this extract had DPPH scavenging activity (IC50 = 109.19 ± 0.77 μg/mL) and cytotoxic activities, the best cytotoxic activity was on HeLa cell (IC50 = 492.23 ± 24,43 μg/mL) with selectivity index (SI) value is 2.33.