Antioxidant and anti-inflammatory constituents from Flos populi

Investigation of the n-butanol extract of Flos populi led to the isolation of one new phenolic glycoside, 4′-hydroxybenzyl-2-hydroxybenzoate-1′-O-β-D-glucopyranoside (1), together with twelve known compounds, which have been determined on the basis of spectroscopic analysis including UV, IR, HR-ESI-MS and 1D/2D NMR. The antioxidant capacity of all compounds were evaluated by ABTS radical-scavenging test and ferric reducing antioxidant power (FRAP) assay. And during a screening procedure for the anti-inflammatory activities among most compounds on lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells, compound 13 exhibited remarkable inhibitory effects on nitric oxide (NO), tumor necrosis factor-α (TNF-α), interleukin (IL)-6 and IL-1β, suggesting that it might be a promising candidate as an anti-inflammatory agent.