Background and Objectives: Multidrug-resistant (MDR) bacteria have emerged as a major global public health concern, substantially limiting the effectiveness of conventional antibiotic therapies and increasing the urgent need for safe, effective, and sustainable alternative antimicrobial agents. In parallel, environmental pollution and the presence of persistent microbial contaminants in water have highlighted the need for innovative treatment technologies. This policy brief aims to provide a comprehensive overview of the antibacterial and photocatalytic properties of biosynthesized silver (Ag) and copper (Cu) nanoparticles and nanocomposites, with particular emphasis on their potential applications in antimicrobial control and environmental remediation. Methods: A literature review was conducted focusing on recent studies investigating the green biosynthesis of Ag- and Cu-based nanoparticles and nanocomposites using medicinal plants and bacteria. The reported antibacterial mechanisms, photocatalytic performance, environmental applications, and potential advantages of biogenic synthesis were critically examined. Policy Options: Biogenic Ag and Cu nanoparticles exhibit enhanced antibacterial and photocatalytic activities against a broad range of microorganisms and environmental contaminants. Their unique physicochemical properties, combined with the use of biological reducing and stabilizing agents, make them promising alternatives to conventional antimicrobial agents and emerging water treatment technologies. Conclusion: Biogenic nanoparticles and nanocomposites synthesized using medicinal plant species and bacteria represent a promising, eco-friendly, and potentially biocompatible approach for addressing antimicrobial resistance and environmental pollution. Further research should focus on optimizing synthesis conditions, elucidating mechanisms, evaluating long-term environmental safety, and facilitating their practical application.
Graphical Abstract
Highlights
Biogenic Ag and Cu nanoparticles exhibit strong antibacterial activity against MDR bacteria.
Green biosynthesis using medicinal plants and bacteria provides an eco-friendly approach.
Ag- and Cu-based nanocomposites show promising photocatalytic potential for environmental remediation.
Biogenic nanomaterials offer sustainable alternatives for antimicrobial control and water treatment.
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Alavi, M., Fattahi, N. & Moradi, M. (2026). Harnessing the power of biogenic nanoparticles for antimicrobial and photocatalytic applications. Environmental Medicine and Toxicology, 1(1), 53–62. https://doi.org/10.22034/emt.2026.600186.1003
MLA
Alavi, M., Fattahi, N., & Moradi, M. "Harnessing the power of biogenic nanoparticles for antimicrobial and photocatalytic applications", Environmental Medicine and Toxicology, 1, 1, 2026, 53–62. doi: 10.22034/emt.2026.600186.1003
HARVARD
Alavi, M., Fattahi, N., & Moradi, M. (2026). 'Harnessing the power of biogenic nanoparticles for antimicrobial and photocatalytic applications', Environmental Medicine and Toxicology, 1(1), pp. 53–62. doi: 10.22034/emt.2026.600186.1003
CHICAGO
Alavi, M., Fattahi, N. & Moradi, M., "Harnessing the power of biogenic nanoparticles for antimicrobial and photocatalytic applications." Environmental Medicine and Toxicology, 1 1 (2026): 53–62, doi: 10.22034/emt.2026.600186.1003
VANCOUVER
Alavi M., Fattahi N., Moradi M. Harnessing the power of biogenic nanoparticles for antimicrobial and photocatalytic applications. Environ Med Toxicol. 2026;1(1):53–62. doi: 10.22034/emt.2026.600186.1003
