The focus of the present study was to evaluate the cytotoxic effects of novel peptide esters derived from galantamine—GAL-LEU and GAL-VAL—on the PC3 prostate cancer cell line. To assess the cytotoxicity of these compounds, the MTT assay, a method that quantifies cellular metabolic activity through the reduction of MTT to formazan, was used. PC3 cells were exposed to different concentrations (ranging from 1.875 μM to 30 μM) of the peptide esters in triplicate. The absorbance of the formazan product was measured using a spectrophotometer at a wavelength of 570 nm. The results showed that GAL-LEU at a concentration of 30 μM inhibited 55.36% of PC3 cell growth, resulting in a cell viability rate of 44.64%. On the other hand, GAL-VAL showed a relatively weaker effect, with a concentration of 30 μM leading to a 43.96% reduction in cell growth. These findings indicate that both peptide esters exhibited cytotoxic activity on the PC3 cells, with GAL-LEU demonstrating a stronger antiproliferative effect than GAL-VAL. The IC50 value for GAL-LEU was 30.8 μM, indicating a more significant inhibitory effect compared to GAL-VAL (IC50 > 30 μM).
