Microwave-Assisted Green Synthesis and Antimicrobial Activity of ZnO Nanoparticles Using Carica Papaya L. Seed Extract

Abstract

Antimicrobial resistance has emerged as a global health concern, jeopardizing the efficacy of infection therapy. Zinc oxide (ZnO) nanoparticles have attracted attention as potential antimicrobial materials that may help address this challenge. Green synthesis using Carica papaya L. seed extract offers a sustainable route for ZnO nanoparticle production, while microwave irradiation may enable rapid, efficient processing. This research examined the properties and antibacterial and antifungal activities of the ZnO nanoparticles produced. ZnO nanoparticles were generated through biosynthesis utilizing Carica papaya L. seed extract as a bioreductant and stabilizing agent via microwave-assisted techniques. The derived ZnO nanoparticles exhibited the defining characteristics of nanomaterials, encompassing ultraviolet-visible (UV-Vis) absorption, chemical interactions, particle size, colloidal stability, crystallinity, shape, elemental composition, and thermal properties. The antibacterial efficacy showed a dose-dependent response against Staphylococcus aureus, Staphylococcus epidermidis, and Candida albicans, with the largest inhibition zone observed against Candida albicans being 23.65 ± 0.25 mm. Statistical analysis revealed that concentration variations significantly influenced antimicrobial activity (p-value less than 0.05). Furthermore, the ZnO nanoparticles synthesized using Carica papaya L. seed extract under microwave irradiation have potential as antimicrobial agents, thereby supporting the United Nations’ Sustainable Development Goals (SDGs), particularly responsible consumption and production (SDG 12) and good health and well-being (SDG 3).