Hybrid Green-Synthesised Silver Nanoparticles from Microbial and Seed Extracts for Efficient Heavy Metal Detoxification

Abstract Toxic heavy metals are a significant source of industrial wastewater, necessitating the development of sustainable treatment methods. Using silver nanoparticles (AgNPs) produced using two environmentally friendly methods—Zanthoxylum armatum seed extract and silver-tolerant Escherichia coli strains—this study presents a novel dual-approach system for effective chromium remediation. The stability, shape, and surface chemistry of the nanoparticles were validated by complete characterization using UV-Vis, FTIR, XRD, SEM, TEM, and zeta potential. Both types of AgNP demonstrated high efficacy in reducing Cr⁶⁺ ions when used alone; however, a synergistic effect with microbial strains significantly increased metal removal, most likely due to improved surface reactivity and colloidal behaviour. The system's effectiveness and repeatability were reinforced by kinetic modelling and statistical validation. Using nanomaterials derived from plants and microbes is a new, environmentally responsible method of treating complex industrial effluents.