Agro-industrial residue-derived silver nanoparticles: synthesis, characterization and their application against challenging pathogens of the built environment

India is among the leading nations in global production of pomegranate and post their utilization in beverage manufacturing sectors, significant volumes of peel waste are generated annually, which is a grave issue from the standpoint of solid waste management. Extrapolating this matter in question in the backdrop of circular economy and sustainable development, this very agro-industrial residue has been valorized in this work, in an attempt to remediate yet another major planetary concern which is, the bio-deterioration of built environment by microbial invasion. The current study used aqueous ethanolic extract from peel waste of <i>Punica granatum</i>, as a reducing agent, to obtain prospective nano-additives for architectural coatings, which were subsequently evaluated using an array of characterization techniques, which confirmed their physicochemical attributes. These were assessed for their antimicrobial efficacy against predominant fungal and bacterial pathogens of the built environment. The highest inhibition of 77.41 ± 2.14% was noted against <i>Cladosporium sphaerospermum</i> and the molecular mechanism of action includes alteration of cell membrane permeability and inhibition of fungal protein synthesis, as confirmed through conductometric and spectrophotometric measurements, respectively. Thus, this study provides a proof of concept that this green synthesized nanomaterial holds a future prospect for nano-functionalization of architectural coatings.