Apoptotic effect of F1 and F2 treatment on MDA-MB-231 cells. (A) Flow cytometric analysis of Annexin V-FITC and propidium iodide (PI) quantifying the F1 and F2-induced apoptosis in MDA-MB-231. Dot plots of MDA-MB-231 cells treated with 0.5% DMSO, 25 or 50 μg/ml of F1or F2 fractions for 48 hours. Viable cells are in the lower left (LL) region (negative for both annexin V-FITC and PI). Early apoptotic cells are located in the lower right (LR) region (annexin V-FITC positive). Late apoptotic cells demonstrating extensive cellular and nuclear membrane damage are located in the upper right (UR) region (double positive). Necrotic cells with destroyed cell membrane are in the upper left (UL) region (PI positive). The results shown are representative of three independent experiments. (B) Bar graphs showing the percentages of cell population of each quadrant in non-treated and treated MDA-MB-231 cells. Data are means ± SEM of three independent experiments.