Discovery of dicephalosterol, a new testosterone 5α-reductase inhibitor, and some new mycological aspects of its producer, Dicephalospora rufocornea (Sclerotiniaceae, Discomycetes)

Abstract

Dicephalosterol, a new testosterone 5α-reductase inhibitor, was found from isolates ofDicephalospora rufocornea, a sclerotiniaceous discomycete widely distributed, but not previously cultured. Under SEM observation, the polar appendage of the ascospores inD. rufocornea was found to be more solid than was hitherto reported. Dicephalosterol was produced by submerged fermentation for 7 d. This new analogue of testosterone showed an IC50 of 5.7 μg/ml for rat prostatic 5α-reductase, but no antimicrobial activity against bacteria or fungi.