Steroids from fungus Engyodontium album associated with the South China Sea cucumber Holothuria nobilis Selenka / 第二军医大学学报

ABSTRACT

Objective To investigate the secondary metabolites of fungus Engyodontium. album (E. album) associated with the South China Sea cucumber Holothuria nobilis (H. nobilis) Selenka. Methods The EtOAc extract of E. album was purified by repeated column chromatography on silica gel, Sephadex LH-20, and high-performance liquid chromatography (HPLC). Structures of the obtainedcompounds were determined by spectroscopic analysis and comparison with previously reported data. Results Five compounds were isolated and their structures were determined as (22E, 2AR)-5a, 8«-epidioxy- ergosta-6, 22-dien-3β-ol (1), (22E, 24iR)-ergosta-5,7, 22-trien-3β-ol (2), (22E, 24iR)-ergosta-7, 22-dien-3β, 5α, 6β-triol (3), 3β, 5«-dihydroxy-(22E, 24iR)-ergosta-7, 22-dien-6-one (4), 3β, 5α-dihydroxy-6β-methoxy-ergosta-7, 22-dien (5). Conclusion This is the first report on the secondary metabolites of E. album associated with the sea cucumber H. nobilis Selenka, and the five compounds have been reported for the first time from the fungus E. album.