Chemical constituents from leaves of Jatropha curcas

OBJECTIVE: To investigate the chemical constituents from the leaves of Jatropha curcas and evaluate their inhibition on lipopolysaccharide (LPS)-activated BV-2 microglia cells. METHODS: The n-BuOH extract of the leaves of J. curcas was isolated by macroporous adsorption resin, silica gel, ODS, column chromatography and semi-preparative HPLC. The structures of the compounds were identified by MS, NMR, ECD, and other spectroscopic methods. In addition, anti-neuroinflammatory effects of isolated compounds were evaluated by measuring the production of nitric oxide (NO) in over-activated BV-2 cells. RESULTS: Seventeen compounds, including (7R,8S)-crataegifin A-4-O-β-D-glucopyranoside (1), (8R,8′R)-arctigenin (2), arctigenin-4′-O-β-D-glucopyranoside (3), (-)-syringaresinol (4), syringaresinol-4′-O-β-D-glucopyranoside (5), (-)-pinoresinol (6), pinoresinol-4′-O-β-D-glucopyranoside (7), buddlenol D (8), (2R,3R)-dihydroquercetin (9), (2S,3S)-epicatechin (10), (2R,3S)-catechin (11), isovitexin (12), naringenin-7-O-β-D-glucopyranoside (13), chamaejasmin (14), neochamaejasmin B (15), isoneochamaejasmin A (16), and tomentin-5-O-β-D-glucopyranoside (17) were isolated and identified. Compounds 2, 4 and 8 significantly inhibited the release of NO in BV-2 microglia activated by LPS, with IC(50) values of 18.34, 29.33 and 26.30 μmol/L, respectively. CONCLUSION: Compound 1 is a novel compound, and compounds 2, 3, 8, 14–17 are isolated from Jatropha genus for the first time. In addition, the lignans significantly inhibited NO release and the inhibitory activity was decreased after glycosylation.