Figure 10
HCT116 cell images were taken under an inverted phase-contrast microscope at × 200 magnification with a digital camera at 48 h after treatment with the samples. A) Cells from the control group showed fully confluent growth with compactly proliferating HCT 116 cells. Treatment with 8 (B), 9 (C) and 10 (D) showed negligible cytotoxicity, as the cell growth did not get affected and cellular morphology was similar to that of negative control. E) Photomicrograph depicts the strong cytotoxic effect of 5-fluorouracil (IC50 = 5.9 μM). It can be seen clearly that the compound affected the normal morphology of all most all the cells of the group which rendered the cells to lose their viability. Except few affected cells, only the cellular debris remained can be seen in the growth medium. F) Treatment with 11 showed significant inhibition in HCT 116 cell proliferation with IC50 = 43 μM, as the population of cells reduced drastically within the 48 h of treatment. The picture revealed that, the treated cells exhibited apoptotic cellular death, which is evident through the appearance of membrane blebbing, nuclear condensation and apoptotic bodies. G) HCT 116 cells treated with the compound 12 exhibited considerable cytotoxicity (IC50 = 44.5 μM). As the photomicrograph depicts the treatment of HCT 116 cells with the compound showed significant inhibitory effect on the cellular growth as compared to the untreated cells. H) Cells treated with the 13 (IC50 = 9.7 μM) showed most potent cytotoxicity among all the tested samples. The activity is comparable to that of standard reference, 5-fluorouracil. The viability of the cells was severely affected, as the photomicrograph showed all the treated cells lost their viable characteristic features.