Anti-inflammatory activity of ingredients from the heartwood of Vietnamese Gamble ex Prain

Abstract

Objectives : To investigate the phytochemical constituents of Vietnamese Dalbergia oliveri and their inhibition of NO production. Methods : The ethyl acetate soluble fraction was subjected to column chromatography using silica gel and Sephadex LH-20 to isolate compounds. The chemical structures of isolated compounds were identified by nuclear magnetic resonance data and comparison with previously reported literature. The anti-inflammation effects of the isolated compounds on the lipopolysaccharide (LPS)-induced NO production in RAW 264.7 cells were measured using the Griess reaction. Results : Nine secondary metabolites ( 1 − 9 ) were isolated successfully from the heartwood of D. oliveri . The chemical structures of these compounds were identified as daidzein ( 1 ), formononetin ( 2 ), 3,7-dihydroxy-4 ′ -methoxyflavone ( 3 ), liquiritigenin ( 4 ), 3 ′ -methoxydaidzein ( 5 ), dalbergin ( 6 ), butin ( 7 ), sativanone ( 8 ), and isoliquiritigenin ( 9 ). This is the first time that compounds 1 , 3 , 5 − 8 have been isolated from D. oliveri . In the NO production inhibition, compounds 7 and 9 exhibited the most potent inhibitory activity, with IC 50 values of 7.6 and 11.2 μM, respectively, followed by 3 − 6 , with IC 50 values from 19.6 to 28.7 μM. Conclusion : The results suggested that D. oliveri and its natural products might exert anti-inflammatory effects due to their NO-inhibiting actions.