Green Synthesis Of Silver Nanoparticles Using Coscinium Fenestratum — A Threatened Medicinal Climber — And Evaluation Of Its Antibacterial Activity

Abstract

The present study reports the green synthesis of silver nanoparticles (AgNPs) using the methanolic extract of Coscinium fenestratum, a threatened medicinal climber renowned for its rich alkaloid content, particularly berberine. The synthesis was carried out via a simple, eco-friendly method, utilizing the phytochemicals in the extract as both reducing and stabilizing agents. The formation of AgNPs was confirmed by a characteristic surface plasmon resonance peak at 430 nm in UV–Vis spectroscopy. Further characterization by Fourier-transform infrared spectroscopy (FTIR) indicated the presence of alkaloids, phenolics, and flavonoids as capping agents. Transmission electron microscopy (TEM) revealed predominantly spherical nanoparticles with an average size of 18–25 nm. The antibacterial activity of the synthesized AgNPs was evaluated against Escherichia coli and Staphylococcus aureus using the agar well diffusion method. The AgNPs exhibited significant antibacterial potential, with inhibition zones of 18.4 ± 0.6 mm and 16.7 ± 0.4 mm, respectively, surpassing that of the crude plant extract. These findings suggest that C. fenestratum-mediated AgNPs hold promise as potent antibacterial agents and underscore the importance of conserving this endangered medicinal species.