Isolation and Characterization of Chemical Constituents from the Poroid Medicinal Mushroom Porodaedalea chrysoloma (Agaricomycetes) and Their Antioxidant Activity

The chemical analysis of the methanol extract of Porodaedalea chrysoloma (Fr.) Fiasson & Niemela afforded the isolation of five compounds (1-5). The first two are phenolic derivatives: methyl (E)-3-(4-methoxycar-bonylphenoxy)-acrylate (1) is a new natural product, while methyl 3-(4-methoxycarbonylphenoxy)-propionate (2) was isolated from a natural source for the first time. The triterpene steroids ergone (3), 3β-hydroxyergosta-7,22-diene (4), and ergosterol (5) have not been previously identified in this species. The structures of the compounds were determined on the basis of NMR and MS spectroscopic analysis. The isolated fungal metabolites 1-5 were evaluated for their antioxidant activity. Compounds 1, 2, and 4 proved to possess considerable antioxidant effect in the ORAC assay with 2.21 ± 0.34, 1.58 ± 0.18, and 5.02 ± 0.47 mmol TE/g, respectively.