Abstract: 　[Objective] To investigate the in vitro and in vivo schizontocidal activity of daphnetin. [Methods] Schizontocidal activity of daphnetin was tested using an in vitro assay based on the routine in vitro cultivation of P. falciparum FCC 1 strain. The in vivo antimalarial effects of daphnetin at various dosages were assessed in mice infected with P b.erghei ANKA according to “4-day suppress assay”. [Results] In vitro ,daphnetin exhibited potent schizontocidal activity comparable to chloroquine(CQ) at the dose range of 1～10 μmol/L. In vivo ,50 or 100 mg/kg.d -1 ×4 d daphnetin i.g. and 10,50 or 100 mg/kg.d -1 ×4 d dephnetin i.p. showed antimalarial efficacy comparable to CQ 10 mg/kg.d -1 ×4 d i.g. in mice infected with P. berghei ANKA, evaluated by both the reduction rate of parasitemia on D 4 and the average surviving days in 30 days. [Conclusion]Daphnetin displays certain schizontocidal activity both in vitro and in vivo .

Key words: daphnetin, Plasmodium falciparum, Plasmodium berghei, schizontocidal activity