Title : Biosynthesis of metallic nanoparticles (MNPs) and their applications in medical, agricultural, and environmental sectors

Nanotechnology is a novel interdisciplinary science that serves as a nexus between the basic sciences and the life sciences, and the life sciences are no exception. As multi-drug resistance in pathogens has rendered antibiotics ineffective, nanoparticles are the next frontier. Silver nanoparticles have been found to have applications in various fields, such as inter-chelating agents. Due to their enhanced responsiveness to environmentally friendly technology for quantifiable synthesis, several developed nations have seen significant growth in the biosynthesis of metallic nanoparticles. The biological method, however, is the most in-demand approach to preparation because it is quicker, safer, less expensive, and more environmentally friendly than other techniques. In addition, the importance of silver, copper, and cobalt has been extensively examined in light of their numerous applications, including antifungal, anti-inflammatory, antibacterial, antiviral, and biocatalytic activities, as well as their use in anticancer medicines. The significant texture of MNPs is their broad-spectrum antimicrobial property, which is attributed to their ability to inhibit microbial colonization associated with biomaterial-related infections. Recent reports indicate that fungi, Viruses, and bacteria are susceptible to metal nanoparticles. In our lab, the biological synthesis of metal nanoparticles, silver, copper, and cobalt, occupying the top slot, uses an eco-friendly approach. Metallic silver nanoparticles are synthesized by the cell-free filtrate of various microbial sources. Viz fungi (Aspergillus niger, Aspergillus flavas, and Agaricus bisphoris ), Actinobacteria (Actinomycetes ), and copper and cobalt from the plant parts (leaves, flowers, stems, etc Using plant sources as reducing agents in the formation of MNPs is particularly attractive due to the process's cost-effectiveness and time-saving nature for MNPS synthesis. In our studies, various plants, including Piper betle, Ocimum leaves, Azadirachta indica, Ficus religiosa, and Ziziphus, are used to synthesize AgNPs. CuNPs & CONPs) FROM Senna alata. The synthesized AgNPs were characterized by UV-visible spectroscopy, FTIR, SEM, and DLS to further examine their biosynthesized efficacy and morphological properties, including size, shape, and stability. The probable mechanism for the extracellular biosynthesis of MNPS (silver) nanoparticles was explained.  The synthesized metallic nanoparticles exhibited excellent antimicrobial activity against bacterial pathogens (E. coli, Staphylococcus, Pseudomonas, Bacillus spp., etc.), including drug-resistant bacteria, plant fungal pathogens (Sclerotium rolfsii, Rhizoctonia bataticola, etc.), and antiviral activity against Sesbania mosaic virus, a causative agent of mosaic disease in Sesbania plants in the agricultural sector.  The biocatalytic nature of MNPs has been tested on textile dyes, such as Methylene Blue (MB) and Bromothymol Blue (BTB). The AgNPs exhibited good decolorization of dyes, which is useful for environmental cleanup.

Professor Narasimha Golla is presently working as Professor and Dean (R&D) at Sri Venkateswara University, India. He focuses on Applied Microbiology and Nanotechnology, specifically bioactive compounds and the characterization of metallic and non-metallic nanoparticles. His work explores their biological applications as antimicrobial, anticancer, antiviral, and biocatalytic agents in modern medicine and bioremediation. He has published over 180 papers in reputable national and international journals, as well as several books and book chapters. His research has been supported by major projects from the Department of Biotechnology, the University Grants Commission, and the Board of Nuclear Sciences, India. Additionally, I serve as an editor and advisory board member for various peer-reviewed journals and maintain active memberships in organizations such as the American Nano Society (AMN) and the Asian Council of Science Editors (ACSE). I also currently serve as the President of the Microbiology Society of India, Andhra Pradesh (MBSI). Narasimha was honored with several recognitions, including being named a Highly Cited Researcher by Elsevier and receiving the World Research Fellow (London, 2025) and the Research Excellence Award. Dr. Narasimha looks forward to the possibility of collaboration and further development of eminence in modern science and technology.