A new cytochalasin from endophytic Phomopsis sp. IFB-E060.

Abstract Aim To study the chemical constituents of the solid culture of the endophyte Phomopsis sp. IFB-E060 in Vatica mangachapoi . Method Isolation and purification were performed through silica gel column chromatography, gel filtration over Sephadex LH-20, ODS column chromatography, and HPLC. Structures of the isolated compounds were elucidated by a combination of spectroscopic analyses (UV, CD, IR, MS, 1D, and 2D NMR). The cytotoxicity of the isolates was evaluated in vitro by the MTT method against the human hepatocarcinoma cell line SMMC-7721. Results Five compounds were isolated from the solid culture of the endophyte Phomopsis sp. IFB-E060 and their structures were identified as 18-methoxy cytochalasin J ( 1 ), cytochalasin H ( 2 ), (22 E , 24 S )-cerevisterol ( 3 ), ergosterol ( 4 ), and nicotinic acid ( 5 ). Compound 1 had an inhibition rate of 24.4% at 10 μg·mL −1 and 2 had an IC 50 value of 15.0 μg·mL −1 , while a positive control 5-fluorouracil had an inhibition rate of 28.7% at 10 μg·mL −1 . Conclusion 18-Methoxy cytochalasin J ( 1 ), produced by endophytic Phomopsis sp. IFB-E060, is a new cytochalasin with weak cytotoxicity to the human hepatocarcinoma cell line SMMC-7721