Constituents from the fruiting bodies ofGanoderma applanatum and their aldose reductase inhibitory activity

Eight compounds were isolated from the fruiting bodies of Ganoderma applanatum, and were identified as 2-methoxyfatty acids (1), 5-dihydroergosterol (2), ergosterol peroxide (3) 3beta,7beta, 20,23xi-tetrahydroxy-11,15-dioxolanosta-8-en-26-oic acid (4), 7beta,20,23xi-trihydroxy-3,11,15-trioxolanosta-8-en-26-oic acid (5), cerevisterol (6), 7beta,23xi-dihydroxy-3,11,15-trioxolanosta-8,20E (22)-dien-26-oic acid (7), and 7beta-hydroxy-3,11,15,23-tetraoxolanosta-8,20E(22)-dien-26-oic acid methyl ester (8) by spectral analysis. All compounds were isolated for the first time from this fruiting bodies, and their effect on rat lens aldose reductase (RLAR) activity was tested. Among these eight compounds, ergosterol peroxide (3) was found to exhibit potent RLAR inhibition, its IC50 value being 15.4 microg/mL.