Potential of Biosynthesized Silver and Zinc Oxide Nanoparticles from Carissa opaca Extracts for Antimicrobial Activity and Wastewater Treatment

The present study focus on biosynthesis of stable silver nanoparticles (AgNPs) and zinc oxide nanoparticles (ZnO NPs) from the leaf and stem extract of a therapeutic plant Carissa opaca. The visual observation, Fourier Transformed Infrared Spectroscopy (FTIR), Inductively Coupled Plasma analysis (ICP), High Resolution Transmission Electron Microscopy (HRTEM), and Scanning Electron Microscopy-Energy Dispersive Spectroscopy (SEM-EDS) were used to characterize and confirm the synthesized AgNPs and ZnO NPs. Afterwards; the synthesized nanoparticles were used to analyze their antimicrobial activity via in-vitro disk diffusion method against Klebsiella pneumoniae, Pseudomonas aeruginosa, Bacillus subtilis, Aspergillus niger, and Candida albican. Both the nanoparticles showed maximum zone of inhibition against Pseudomonas aeruginosa (bacterial strain), whereas in the case of fungi, higher zone of inhibition was observed using ZnONPs against Candida albican and AgNPs against Aspergillus niger. The biosynthesized AgNPs was also used for degradation of methylene blue under visible-light irradiation and found dye removal efficiency of. 97.4% within 1 h.