In vitro potentiation of antimalarial activities by daphnetin derivatives against Plasmodium falciparum / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To screen the antimalarial compounds of daphnetin derivatives against Plasmodium falciparum in vitro.</p><p><b>METHOD</b>Plasmodium faciparum (FCC1) was cultured in vitro by a modified method of Trager and Jensen. Antimalarial compounds were screened by microscopy-based assay and microfluorimetric method.</p><p><b>RESULTS</b>DA79 and DA78 showed potent antimalarial activity against Plasmodium falciparum cultured in vitro.</p><p><b>CONCLUSION</b>Though the relationship between the structures of daphnetin derivatives and their antimalarial activities has not been clarified yet, this study may provide a new direction for discovery of more potential antimalarial compounds.</p>

Comparative study on schizontocidal activity of recrystallized or crude daphnetin against malaria parasites / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To compare the schizontocidal activity of recrystallized or crude daphnetin against malaria parasites in vivo.</p><p><b>METHODS</b>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".</p><p><b>RESULTS</b>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.</p><p><b>CONCLUSION</b>The results indicate that the efficacy of recrystallized daphnetin is 37.6% higher than that of crude daphnetin.</p>