Green-synthesized silver and zinc oxide nanoparticles: A mini review of antibacterial and antimycobacterial activities

The escalating challenge of antimicrobial resistance (AMR), particularly in multidrug-resistant Mycobacterium tuberculosis , emphasizes the urgent need for innovative antimicrobial strategies. The green synthesis of silver (AgNPs) and zinc oxide nanoparticles (ZnONPs) using plant-derived phytochemicals offers an eco-friendly alternative to conventional chemical methods, combining sustainability with enhanced biological efficacy. This review summarizes the recent advances in the green synthesis of AgNPs and ZnONPs, emphasizing their structural characterization and antibacterial and antimycobacterial activities. Key mechanisms include membrane disruption, reactive oxygen species (ROS) generation, and metal ion release, and phytochemical capping agents further improve stability and biocompatibility. Comparative analysis revealed that AgNPs generally exhibit superior antibacterial potency, whereas ZnONPs demonstrate greater biocompatibility and versatility for biomedical applications. Despite promising in vitro and in vivo findings, clinical translation is limited by challenges in terms of reproducibility, toxicity profiling, and regulatory approval. Future research should prioritize standardized synthesis protocols, long-term toxicity evaluations, and the development of multifunctional nanocomposites, such as Ag/ZnO hybrids. By bridging sustainable nanotechnology with biomedical innovation, green-synthesized nanoparticles have great potential as next-generation agents to combat drug-resistant infections and to address global health challenges.