Fig. 2. : effect of Piper aduncum essential oil (PaEO) on Trypanosoma cruzi epimastigotes, as analysed by flow cytometry. (A-B) Cell cycle analysis. Epimastigotes were treated for 24 h at 28°C with the IC50/24 h value of PaEO and then incubated with propidium iodide (PI). (A) Histograms of the PI-stained cell populations; (B) mean number of cells in each cell cycle stage. *: p < 0.05. (C-D) Mitochondrial membrane potential analysis. Epimastigotes were kept for 24 h at 28°C with the IC50/2 h value of PaEO and then incubated with Rhodamine-123. CCCP (carbonyl cyanide 3-clorophenylhydrazone): positive control. (C) Histograms of the Rhodamine-123-stained populations; (D) percentage of labelled cells after each treatment.