Synthesis of Luminescent Copper Nanoparticles Using Couroupita guianensis Flower Extract: Evaluation of Antibacterial and Anticancer Activities

The biosynthesis of nanoparticles is a crucial research area aimed at developing innovative, cost‐effective, and eco‐friendly synthesis techniques for various applications. Herein, we synthesized copper oxide nanoparticles (CuNPs) using Couroupita guianensis flower extract via a simple green synthesis method. These green CuNPs demonstrate promising antimicrobial activity and anticancer activity against A549 nonsmall cell lung cancer (NSCLC) cells. We comprehensively characterized the CuNPs using UV spectrum, XRD, FTIR, SEM, and EDS analyses. The antibacterial and anticancerous performance is attributed to their spherical‐like morphology, which enhances effective interaction with bacterial and cancer cells. Moreover, CuNPs proved effective in inactivating Escherichia coli, achieving 2%, 52%, and 99% inactivation at 0, 30, and 60 min, respectively, and Listeria monocytogenes, achieving 1%, 48%, and 98% inactivation at 0, 30, and 60 min, respectively, under visible light. Furthermore, the CuNPs exhibited significant anticancer activity against A549 NSCLC cells, achieving cell viability reductions of 10%, 30%, 50%, 70%, 83%, and 91% at concentrations of 25, 50, 100, 150, 200, and 250 μg/mL, respectively. The green synthesized CuNPs demonstrate their potential in biomedical applications. CuNPs synthesized using Couroupita guianensis flower extract through a green synthesis method exhibited significant antimicrobial and anticancer properties. The CuNPs demonstrated effective antimicrobial activity against E. coli and L. monocytogenes under visible light, with the spherical morphology contributing to their enhanced interaction with bacterial cells.