Characterisation of Flavonoids fromBaccharis trimeraand their Antihepatotoxic Properties*

From the crude ethyl acetate extract of the epigeous parts of Baccharis trimera Less. (Compositae, tribe Astereae) 5 flavonoids were isolated and identified: Quercetin ( 1 ), luteolin ( 2 ), nepetin or eupafolin ( 3 ), apigenin ( 4 ), and hispidulin ( 5 ). Antihepatotoxic activity was investigated in mice intoxicated with phalloidin. The crude flavonoid extract administered intravenously in a dose of approximately 20 mg/kg 1 h before intoxication increased the survival rate from 25% to 100%. The most active of the pure components was hispidulin (32 mg/kg) ameliorating survival rate to 80%. A mixture of all 5 flavonoids in equal weight relations (final dose: 35 mg/kg) increased the survival rate to 70%. The efficacy of the crude extract seems to be explained to a large extent by the identified compounds.