Antibacterial potential of biosynthesized silver nanoparticles using phycocyanin of freshwater cyanobacterium Oscillatoria pseudogeminata

The aim of the study is biosynthesis and characterization of silver nanoparticles (AgNPs) using phycocyanin of Oscillatoria pseudogeminata which was isolated from freshwater pond in Karaikudi district, Tamil Nadu and mass cultivation for phycocyanin extraction and was quantified by UV visible spectrum. The synthesized AgNPs were characterized by UV–Vis spectroscopy, FT–IR, XRD, SEM, and zeta potential. UV–Vis spectrum revealed a characteristic surface plasmon resonance peak at 445 nm, which corresponds to the absorption band of AgNPs. A shift in the absorption bands in FT–IR after the formation of AgNPs was confirmed. X-ray diffraction analysis showed that the AgNPs were crystalline in nature. Zeta potential of AgNPs showed − 19.5 mV. The synthesized AgNPs have shown a antibacterial activity against bacterial pathogens of S. aureus and P. aeroginosa. Moreover, the synthesized AgNPs have a minimum inhibitory concentration (MIC) of 750 µg/mL against S. aureus. This study elaborated the process of biosynthesized AgNPs formation via the green chemistry approach for further application.