Figure 3

Dose-dependent effects of maslinic acid on P. falciparum cultures compared to chloroquine and atovaquone. Synchronized cultures of Dd2 at mature ring stage (22 h, 1% parasitaemia) were incubated for 48 hours with the compounds at the indicated concentrations and compared to an untreated control. Cultures were evaluated by microscopic inspection of Wright's-stained thin blood smears. A. Microscopic images of P. falciparum cultures incubated with different concentrations of maslinic acid, chloroquine and atovaquone. Delayed trophozoites (Y) and pyknotic forms (X) showing condensation of the parasite nucleus are highlighted. B. Parasitaemia of the previous cultures after 48 h MA treatment. Results are the mean ± SD of three independent experiments. C. Parasitic stages observed in cultures treated with different concentrations of MA, chloroquine and atovaquone for 48 hours. Bars show percentage of rings (white), trophozoites (grey), schizonts (black) and pyknotic (hatched) forms observed in Dd2 cultures treated at the indicated compound concentrations. The percent of each group accounts for the fraction of cells showing every parasite stage from a total of 1000 erythrocytes ± SD. Results are representative of 2 experiments.