Anti-inflammatory glycosides isolated from the aerial parts of Morinda parvifolia

The plant Morinda parvifolia is traditionally used as an herbal medicine for the treatment of dyspepsia, tracheitis, and coughing. The ethyl acetate extract of the aerial parts of M. parvifolia showed significant inhibition against ear edema in mice induced by croton oil (36.4% inhibition). Four undescribed glycosides, 2-hydroxymethyl anthraquinone-3-O-beta-primeveroside, p-hydroxy benzoic acid 4-O-beta-D-(6'-O-sinapoyl) glucopyranoside, gentisic acid 5-O-beta-D-(6'-O-sinapoyl) glucopyranoside, and 2-[(beta-D-glucopyranosyloxy) methyl]-benzoic acid, together with 20 known glycosides were isolated from the ethyl acetate extract. The structures of these undescribed compounds were elucidated by comprehensive spectroscopic analysis. Eight glycosides showed anti-inflammatory activities, which could inhibit the mRNA expression of IL-6 with IC50 values of 55.4 +/- 0.20-85.2 +/- 0.05 mu M, respectively.