Differential Cytotoxic Effects of Opuntia ficus-indica Fractions Against Colon Cancer Cells

Abstract

Opuntia ficus-indica (OFI) is a source of diverse phytochemicals with reported antitumoral activities; however, the specific compounds responsible for cytotoxicity in colorectal cancer (CRC) cells and their underlying mechanisms remain unclear. This study evaluated the cytotoxic, redox-modulating, and mitochondrial effects of different OFI extracts obtained via sequential exhaustive extraction (SEE) with hexane, petroleum ether, ethyl acetate, acetone, butanol, ethanol, and water on human colorectal adenocarcinoma Caco-2 cells. Ethyl acetate (EA) and water (W) extracts exhibited the strongest cytotoxicity at 100 μg/mL, reducing cell viability to 43.07% and 63.80%, respectively, whereas the remaining extracts showed no significant effects. EA extract decreased mitochondrial membrane potential and simultaneously reduced intracellular reactive oxygen species (ROS), indicating a cytotoxic mechanism independent of oxidative stress. The phytochemical profile showed a high concentration of flavonoids in the EA extract, consistent with the observed antioxidant effect. These results demonstrate that the antitumoral activity of OFI is strongly solvent-extraction-dependent, highlighting the EA extract as the most promising candidate for the development of antitumoral therapies. These findings support OFI as a source of potential antitumoral molecules and encourage future evaluation of mechanistic pathways and selectivity toward healthy colon cells.