Chemical and activity investigation on metabolites from the endophytic fungus Penicillium macrosclerotiorum isolated from Ilex pubescens Hook. et Arn

Penicillium macrosclerotiorum was isolated for the first time from the leaves of Ilex pubescens Hook. et Arn (VSN-2022-03-18-001) and found to produce bioactive compounds. Seven compounds were obtained from the fermentation broth and mycelia of P. macrosclerotiorum and identified as palmitic acid (1), methyl 6-acetyl-5,7,8-trihydroxy-4-methoxy-2-naphthoate (2), ergosterol (3), daidzein (4), oleuropein (5), pedunculoside (6) and acteoside (7). Compounds 3, 4 and 7 exhibited antioxidant activity against diphenyl picryl hydrazinyl with IC50 values of 58.06, 2.58 and 12.01 µg/mL, respectively. Compounds 3, 5 and 7 exhibit inhibitory activity against Escherichia coli with MIC values of 0.78, 3.13 and 3.13 mg/mL, while compounds 2, 3, 4, 5, 6 and 7 exhibited inhibitory effect on Candida albicans with MIC values of 0.20, 0.20, 0.39, 0.63, 0.78 and 0.78 mg/mL, respectively. Furthermore, Compound 4 effectively inhibited HepG2 cells, showing an IC50 of 34.03 μg/mL.