Production of xanthones with free radical scavenging properties, emodin and sclerotiorin by the cultured lichen mycobionts of Pyrenula japonica

摘要

From the cultures of the spore-derived mycobionts of the lichen Pyrenula japonica, two new xanthones, 1,8-dihydroxy-3-hydroxymethyl-5-methoxyxanthone and 1,2,8-trihydroxy-5-methoxy-3-methylxanthone, were isolated along with 1,7-dihydroxy-3-methylxanthone, 1,5,8-trihydroxy-3-methylxanthone, 1,8-dihydroxy-5-methoxy-3-methylxanthone, emodin and sclerotiorin. Their structures were determined by spectroscopic methods. Sclerotiorin was isolated for the first time from lichen mycobionts. Radical scavenging activities of the isolated xanthones were also studied. [References: 10]