Eco-Friendly Biosynthesis of Nanoparticles from Moringa oleifera Leaves and Their Biological Activities

Abstract

Green synthesis of nanoparticles has emerged as an environmentally friendly and sustainable alternative to conventional physical and chemical synthesis methods. In the present study, silver nanoparticles (AgNP_S) were synthesized using Moringa oleifera leaf extract through a simple, cost-effective, and eco-friendly biological approach. The phytochemicals present in the plant extract acted as reducing and stabilizing agents during nanoparticle formation. Successful biosynthesis of AgNP_S was initially confirmed by a visible color change from light yellow to dark brown and further supported by UV–Visible spectroscopy, which revealed a characteristic surface plasmon resonance (SPR) peak around 430 nm. The proposed phytochemical-mediated mechanism suggested the involvement of phenolics, flavonoids, proteins, and other secondary metabolites in the reduction and stabilization of silver nanoparticles. The synthesized AgNP_S exhibited promising antibacterial activity against both Gram-positive and Gram-negative bacterial strains, including Staphylococcus aureus and Escherichia coli. In addition, the nanoparticles demonstrated considerable antioxidant activity in the DPPH radical scavenging assay, indicating their potential biomedical and pharmaceutical applications. The findings of this study highlight the effectiveness of plant-mediated green synthesis for producing biologically active silver nanoparticles and support the growing potential of sustainable nanotechnology for future medical, pharmaceutical, environmental, and industrial applications.