CHEMICAL AND PRELIMINARY ANALGESIC EVALUATION OF GERANIIN AND FUROSINISOLATED FROM PHYLLANTHUS-SELLOWIANUS

The present study describes the occurrence of two ellagitannins in the ethanolic extract of the leaves and stems of Phyllanthus sellowianus (Euphorbiaceae). Their preliminary antinociceptive properties were als o evaluated. The two ellagitannins were identified on the basis of H-1 - and C-13-NMR spectra data and by mixed co-TLC and co-HPLC injection with an authentic sample of furosin and geraniin. Preliminary pharmaco logical analysis revealed that both furosin and geraniin (3 to 30 mg/k g, i.p.), given 30 min before testing, exhibited significant and dose- related antinociceptive properties against acetic acid-induced abdomin al constrictions in mice. Geraniin and furosin were about six- to seve n-fold more potent at the ID50 level (mu mol/kg) as analgesics than as pirin and acetaminophen, respectively, although they were less efficac ious when compared with the standard drugs. These data extend our prev ious studies and indicate that the two ellagitannins isolated from P. sellowianus, identified as furosin and geraniin, are, at least in part , responsible for the antinociceptive actions reported previously for the hydroalcoholic extract of P. sellowionus and other plants belongin g to the genus Phyllanthus.