Ecofriendly Biosynthesis of Zinc Oxide Nanoparticles (ZnO NPs) from Arthrospira platensis and Their Assessment for Antimicrobial, Antibiofilm, Anticancer Potency and Alleviation of Copper Stress in Vicia faba (L.) Plant

Abstract Purpose This study aims to biosynthesize zinc oxide nanoparticles (ZnO NPs) by using the metabolites from the cell debris of Arthrospira platensis . ZnO NPs have reduced copper toxicity (Cu 2+ ) in Vicia faba (L.) seedlings, and antibacterial, antibiofilm, and anticancer properties were investigated. Methods The ZnO NPs were analyzed by X-ray diffraction, transmission electron microscopy, scanning electron microscopy, Fourier transform infrared (FTIR), and UV–visible spectroscopy. Results The characterization of ZnO NPs was spherical and ranged from 11 to 20 nm and FTIR analysis confirmed the nanoparticles with specific absorption peaks. The ZnO NPs exhibited antimicrobial activity, strong antibiofilm activity, and were effective in the cytotoxic killing of Hep-G2 cancer cells. The growth attributes of 21-day-old Vicia faba seedlings were negatively impacted by copper stress. However, applying ZnO NPs at varying doses improved the seedlings' physiological and morphological characteristics. Conclusion ZnO NPs have potential applications in enhancing plant tolerance to environmental stress and can be employed as potent anticancer, antibacterial, and antibiofilm agents, with potential benefits in agriculture.