Antioxidant Anti-Glycation and Anti-Inflammatory Activities of Phenolic Constituents from Cordia sinensis

摘要

Nine compounds have been isolated from the ethyl acetate soluble fraction of C. sinensis, namely protocatechuic acid (>1), trans-caffeic acid (>2), methyl rosmarinate (>3), rosmarinic acid (>4), kaempferide-3-O-β-D-glucopyranoside (>5), kaempferol-3-O-β-D-glucopyranoside (>6), quercetin-3-O-β-D-glucopyranoside (>7), kaempferide-3-O-α-L-rhamnopyranosyl (1→6)-β-D-glucopyranoside (>8) and kaempferol-3-O-α-L-rhamno-pyranosyl (1→6)-β-D-glucopyranoside (>9), all reported for the first time from this species. The structures of these compounds were deduced on the basis of spectroscopic studies, including 1D and 2D NMR techniques. Compounds >1–9 were investigated for biological activity and showed significant anti-inflammatory activity in the carrageen induced rat paw edema test. The antioxidant activities of isolated compounds >1–9 were evaluated by the DPPH radical scavenging test, and compounds >1, >2, >4 and >7>–9 exhibited marked scavenging activity compared to the standard BHA. These compounds were further studied for their anti-glycation properties and some compounds showed significant anti-glycation inhibitory activity. The purity of compounds >2>–5, >8 and >9 was confirmed by HPLC. The implications of these results for the chemotaxonomic studies of the genus Cordia have also been discussed.