Assessment of Antioxidant and Anticancer Activities of <i>Erythrina variegata</i> L. Leaves Collected from Ketambe Against A549 Lung Cancer Cell Line

Erythrina variegata L. (Dadap) has been traditionally utilized as a medicinal plant. In this study, its antioxidant capacity was examined using the DPPH radical scavenging assay, while cytotoxic activity was evaluated against A549 lung cancer cells and Chang normal cells through the MTT assay. The methanolic extract of Dadap leaves showed moderate antioxidant activity with an IC50 of 177.354 ppm. Cytotoxicity tests revealed strong activity against A549 cells with an IC50 of 66.640 ppm, while showing weak toxicity toward Chang cells (IC50 of 324.283 ppm), even slightly promoting normal cell growth. The extract demonstrated a selectivity index (SI) of 4.866, indicating selective cytotoxicity toward lung cancer cells (SI ≥ 2). GC–MS analysis identified 26 compounds, with the predominant bioactive metabolites being neophytadiene, methyl hexadecanoate, methyl (9Z,12Z)-octadecadienoate, phytol, 3,7,11,15-tetramethyl-2-hexadecen-1-ol, and stigmasterol, all of which have been associated with antioxidant and anticancer activities. Complementary LC–HRMS profiling detected 568 compounds, of which 22 were characterized as major constituents, including seven alkaloids—1,2-dimethoxy-6aβ-noraporphine, bohemamine F, peniamidienone, codeinone, sinomenine, 6β-naltrexol, and (S)-corytuberine—and one flavonoid, isovitexin 2''-O-arabinoside. These metabolites support the potential of E. variegata L. methanolic extract as an antioxidant and anticancer agent.