Abstrakt: |
ALCHORNEA FLORIBUNDA (Euphorbiaceae) leaves are widely used in African ethnomedicine for the management of acute and chronic inflammatory disorders. In the present study, bioactivity-guided fractionation led to the isolation of two known ( 1 and 3) and one new ( 2) stigmastane steroids from the hexane extract of ALCHORNEA FLORIBUNDA leaves. The anti-inflammatory activities of these compounds were evaluated using IN VITRO and IN VIVO animal models. The compounds 1, 2, and 3 at 50 and 100??g/ear significantly (p?0.05) inhibited xylene-induced ear edema in mice in a dose-dependent manner. The topical anti-inflammatory effect of 1 and 2 are significantly (p?0.05) higher than that of indomethacin and prednisolone. At 20?mg/kg (i.?p.), all the compounds significantly (p?0.05) inhibited acute inflammation induced by subplantar injection of egg albumen in rats. Compound 1 exhibited an anti-inflammatory effect (50.9?% edema inhibition) comparable (p?0.05) to that of prednisolone (48.0?% edema inhibition) at 3?h. Compounds 1, 2, and 3 (50??g/mL) significantly (p?0.05) inhibited heat-induced haemolysis of human erythrocytes IN VITRO, but had no effect on hypotonicity-induced hemolysis. The compounds were elucidated as (24R)-5?-stigmast-3,6-dione ( 1), 5?-stigmast ??23-ene-3,6-dione ( 2), and 3?-hydroxy-5?-stigmast-24-ene ( 3) by spectral analysis. The results of this study show that these compounds may, in part, account for the anti-inflammatory effect of ALCHORNEA FLORIBUNDA leaves. This is the first report on the isolation and structure elucidation of these anti-inflammatory steroids from ALCHORNEA FLORIBUNDA leaves. [ABSTRACT FROM AUTHOR] |