Bioactive metabolites isolated from Penicillium sp. YY-20, the endophytic fungus from Ginkgo biloba.

Six known metabolites, adenosine (1), methyl β-D-ribofuranoside (2), adenine (3), 2'-deoxyadenosine (4), 3-methylpiperazine-2,5-dione (5) and 2'-deoxyuridine (6), were isolated from the extracts of the endophytic fungus Penicillium sp. YY-20 isolated from the root of Ginkgo biloba, and their structures were elucidated by spectroscopic methods. The antioxidant and growth-promoting activities of these compounds were first evaluated. The results indicated that compounds 1, 3 and 4 exhibited potential DPPH-scavenging activities compared with positive control. In addition, all the compounds (except 5) stimulated seed germination of Raphanus sativus, Brassica napus and Brassica chinensis but had weak stimulating effect on their root and hypocotyl growth.