ABSTRACT
Objective:To study the secondary metabolites of the endophytic fungus Trichoderma harzianum,which was isolated from Physalis angulata. Method:The strains were cultured in a big-scale by oscillating incubator. Then the obtained culture liquid and mycelia were extracted by EtOAC and actone,respectively. The extracts were integrated after recovery of solvents, and then the active secondary metabolites were isolated and purified by comprehensive use of open ODS flash column,sephadex LH-20,HPLC,and LC-MS analysis techniques. Their structures were identified according to their physico-chemical properties and nuclear magnetic resonance (NMR) data. The cytotoxicities of the compounds were determined by methyl thiazolyl tetrazolium(MTT) assay. Result:Ten compounds isolated from T. harzianum were identified as destruxin A2(1),destruxin B2(2),3-isobutyl-pyrrolopiperazine-2,5-dione[cyclo (leu-pro dipeptide)](3),cyclo (Phen-pro) dipeptide(4),cyclonerodiol(5),brevianamide F(6),N-acetyltryptamine(7),9-hydroxyl-(2-methylpropyl) isobutyl phthalate(8),5-hydroxy-3-hydroxymethyl-2-methyl-7-methoxychromone(9),and phenylpropionic acid(10). Compounds 1-10 didn't exhibit significant cytotoxicity to lung cancer cell line A549 in the MTT assay (IC50 ≥ 20 mg·L-1). Conclusion:All compounds were isolated from T. harzianum for the first time.
ABSTRACT
By means of various chromatographic methods such as Sephadex LH-20，ODS，and semi-preparative HPLC，ten compounds were isolated from Streptomyces sp. A1693 and their structures were elucidated on the basis of spectroscopic data and physico-chemical methods. The compounds comprised 5 butenolides，2 diketopiperazines，and 3 antimycin antibiotics. The structures were identified as (5)-5-(11-hydroxymethyloctyl)furan-2(5)-one (1), (5)-5-(11-hydroxy-11-methylheptyl)furan-2(5)-one (2), (5)-5-(11-methyl-12-oxooctyl) furan-2(5)-one (3), (5)-5-(11-hydroxy-11-methyloctyl)furan-2(5)-one (4), (5)-5-(11-hydroxy-12-methyloctyl)furan-2(5)-one（5），cyclo-Phe-Val (6)，cyclo-Phe-Ile (7)，uranchimycin A (8)，uranchimycin B (9)，and deisovalerylblastomycin (10). Among them，1 was defined as a new compound. All the compounds didn't show the cytotoxic activity against A549 cell line (IC₅₀>50 mg·L⁻¹).