Secondary metabolites of the fungus Aspergillus austroafricanus isolated from a soft coral
Objective To investigate the secondary metabolites of the Aspergillus austroafricanus(18XS04ZP-2)isolated from a soft coral Plakortis galapagenis collected from the Xisha islands.Methods The secondary metabolites of the strain were separated and purified by thin layer chromatography(TLC),silica gel column chromatography,SephadexLH-20 gel column chromatography,medium pressure liquid chromatography(MPLC)and high performance liquid chromatography(HPLC).Through modem spectroscopy methods such as NMR and MS,combined with relevant literature data analysis to identify the structure of the compound.Results Ten compounds were isolated from Aspergillus austroafricanus(18XS04ZP-2),and they were identified as 4-hydroxy-17R-meth-ylincisterol(1),chaxines B(2),volemolide(3),(22E,24R)-24-methylcholesta-7,22-dien-3β,5α,6β-triol(4),(22E,24R)-6β-methoxyergosta-5,22-diene-3β,5α-diol(5),(22E,24R)-3β,5α,9α-trihydroxy-ergosta-7,22-dien-6-one(6),6-dehydrocerevisterol(7),averufanin(8),versicolorin A(9),nidurufin(10).Compound 2 exhibited inhibitory activity against K562 with the IC50 value of 8.68 μmol/L.