Biosynthesis of silver nanoparticles using Aristolochia bracteolata Lam. ethyl acetate extract: Characterization and In Vitro anticancer activity against lung adenocarcinoma cells

Lung cancer remains a leading cause of cancer-related mortality, necessitating novel therapeutic strategies. Aristolochia bracteolata Lam. has been traditionally studied for its potential in cancer treatment, and this study explores the green synthesis of silver nanoparticles (AgNPs) using its ethyl acetate extract to evaluate their anticancer potential against human lung adenocarcinoma (NCIH-460) cells. AgNPs biosynthesis was confirmed by a color change and characterized by UV-Vis spectroscopy, FTIR, XRD, zeta potential FE-SEM, and TEM. The UV-Vis spectrum exhibited a characteristic absorption peak at 450 nm, confirming nanoparticle formation. XRD analysis indicated the crystalline nature of AgNPs, while FTIR spectra identified key functional groups involved in nanoparticle stabilization, including O-H, C-H, CC, and C-O bonds. FE-SEM and TEM images showed polydispersed, mostly spherical AgNPs ranging from 4 to 171 nm, with an average TEM-derived size of 10 nm. Zeta potential analysis showed a charge of −26 mV, suggesting moderate stability in solution. The AgNPs exhibited potent cytotoxicity against NCIH-460 cells (IC₅₀ = 13.44 µg mL⁻¹) while sparing normal L929 cells (IC₅₀ = 196.05 µg mL⁻¹). Annexin V/PI and TUNEL assays confirmed apoptosis induction, while cell cycle analysis demonstrated G0/G1 phase arrest, supported by caspase-3 upregulation. These findings suggest biosynthesized AgNPs as promising anticancer agents, capable of inducing apoptosis and disrupting cancer cell proliferation, making them potential candidates for lung cancer therapy.