Comparative study on schizontocidal activity of recrystallized or crude daphnetin against malaria parasites

To compare the schizontocidal activity of recrystallized or crude daphnetin against malaria parasites in vivo.Schizontocidal activity of recrystallized or crude daphnetin at various dosages was assessed in mice infected with Plasmodium berghei ANKA using a "4-day suppress assay".The comparison of the reduction rate of parasitemia caused by either recrystallized or crude dephnetin showed that ED(50) of crude daphnetin was 18.36 mg/kg, with 95% confidence limit of 5.96-56.54 mg/kg while ED50 of recrystallized daphnetin was 11.46 mg/kg, with 95% confidence limit of 8.63-15.22 mg/kg.The results indicate that the efficacy of recrystallized daphnetin is 37.6% higher than that of crude daphnetin.