Zerumbone Induces Apoptosis in Non-Small-Cell Lung Cancer via Biomolecular Alterations: A Microscopic and Spectroscopic Study

Zerumbone is a sesquiterpene phytochemical with cytotoxic activity against cancer. This study aimed to evaluate the effect of zerumbone on cell viability by WST-1 test, apoptosis by TUNEL, lipid peroxidation markers (malondialdehyde, MDA, and 4-hydroxynonenal, HNE) by using assay kits, and biomolecular changes by ATR-FTIR spectroscopy in A549 cells. After zerumbone (0–100 μM) incubation for 24, 48, and 72 h, the number of TUNEL-positive cells was found to be higher in zerumbone-treated cells than in controls, in consistent with cell morphology results. MDA levels increased significantly, although HNE levels increased non-significantly in zerumbone-treated cells. Spectral analyses revealed that the zerumbone-treated groups had higher levels of total saturated and unsaturated lipids as well as comparatively shorter-chain lipids. On the contrary, reduced RNA/DNA ratio, total nucleic acid, and protein content were found in zerumbone-treated groups. Consequently, zerumbone-induced apoptosis was accompanied by increased aldehyde products during lipid peroxidation as well as biomolecular alterations.