Abstract
Vitex negundo is a traditional medicinal plant known for its anticancer properties, particularly its effectiveness in targeting apoptosis-related cancer pathways. Colorectal cancer is the most prevalent malignancy worldwide, often requiring alternative therapies involving plant-derived bioactive compounds. This study aimed to synthesize zinc oxide nanoparticles using V. negundo leaves (VnZnONP) and confirm their formation through characterization studies. Further, the anticancer efficacy of VnZnONPs was also evaluated in HT-29 colorectal cancer cells. Zinc oxide nanoparticles were synthesized using methanolic leaf extract of V. negundo (MeVn), which contained nearly 39 phytocompounds, identified in gas chromatography-mass spectrometry (GC-MS). UV-vis spectroscopy showed a prominent peak at 374 nm, while dynamic light scattering (DLS) revealed a size distribution peaking at 452.5 nm. In SEM analysis, the spherical-shaped morphology with random distribution was observed. EDX analysis confirmed the presence of zinc and oxygen, and zeta potential analysis showed a + 41.4 mV charge, indicating stable nanoparticles. FTIR analysis identified functional groups such as aliphatic, aromatic compounds, alkenes, alcohols, and amides. In the DPPH assay, VnZnONP at 100 µg/ml exhibited 87.96% antioxidant activity, significantly higher than MeVn (39.89%). VnZnONPs showed dose-dependent cytotoxicity against HT-29 cells with an IC(50) value of 60.56 µg/ml. In addition, DAPI staining confirmed nuclear damage, and acridine orange/ethidium bromide staining indicated early and late apoptosis. RT-PCR analysis revealed downregulation of Jab1 and Bcl2, and upregulation of Bax, Caspase-3, and Caspase-9. This study demonstrates that V. negundo-based ZnO nanoparticles can promote apoptosis and can serve as a promising therapeutic agent for colorectal cancer. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10616-025-00775-x.