Secondary metabolites of co-culture of Alternaria alternate YX-25 and Streptomyces exfoliatus YX-32 / 中草药

ABSTRACT

Objective To study the secondary metabolites of the co-culture of fungus Alternaria alternata YX-25 and Streptomyces exfoliatus YX-32 isolated from mangrove mud in Yunxiao Country of Fujian Province. Methods The compounds were purified by silica gel and Sephadex LH-20, followed by semi-preparative chromatography. The structures of the compounds were determined by MS and NMR. Results Nine compounds were isolated from the crude extract, which were identified as gliotoxin (1), 12,13-dihydroxy-fumitremorgin C (2), fumitremorgin (3), bisdethiobis(methylthio)gliotoxin (4), demethoxyfumitremorgin C (5), vermistatin (6), cyclo-(L-Trp-L-Pro) (7), 6-methoxyspirotryprostatin B (8), and citrinolactone D (9). Conclusion Nine compounds were isolated for the first time from co-culture of the fungus Alternaria alternata YX-25 and Streptomyces exfoliates YX-32, including indole diketopiperazines, polyketides, and cyclopeptides. The co-cultivation method can be as a new method for enrichment of secondary metabolites.