Ten new 9,11 secosterols isolated from the Formosan corgonian coral Pinnigorgia sp.

Abstract

Induction of hepatic stellate cells (HSC) apoptosis by natural products is considered an effective strategy for treating liver fibrosis. The marine environment may be explored as a rich source for novel drugs. Multiple studies have been carried out to characterize marine bioactive compounds with an aim to cure human diseases and conditions; the focus on liver diseases is very limited. Using our experience searching for new bioactive compounds from soft corals and gorgonian corals, we carried out the first chemical investigation on the gorgonian coral Pinnigorgia sp. with the aim of discovering interesting new natural products and ten new 9,11-secosterols 1-10 were isolated. Structures of sterols 1-10 were elucidated by spectroscopic methods, particularly with 2D NMR experiments. In bioactivity test, cytotoxicity of sterols 1-10 against the proliferation of HSCs was evaluated. The results showed that sterol 1 inhibited cell viability of HSC-T6 with an IC50 value of 6.21 ± 0.14 µM. Thus, Steroid 1 could be a promising bioactive agent and may warrant further biomedical investigation.