Green synthesis of silver nanoparticles using ocimum americanum aqueous leaf extract and study of its antimicrobial activity against esbl and mbl producing pathogens

The present study reports the synthesis of silver nanoparticles (Ag-NPs) using aqueous extract of Ocimum americanum (L.) leaf and silver nitrate (AgNO3) solution. The synthesized Ag-NPs were analysed using UV-Visible Spectroscopy (UV-Vis), Scanning Electron Microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FTIR). The UV-Vis spectrum ofAg-NPs in aqueous solution showed an absorbance peak around 424nm, which is a characteristic property of nanoparticle formation. The antimicrobial property of Ag-NPs was analyzed by qualitative methods like disc and well diffusion method against Extended Spectrum β-Lactamase (ESBL) and Metallo β-Lactamase (MBL) producing E.coli, Pseudomonas, Proteus, Citrobacter and Klebsiella species. The mean zones of inhibition for Ag-NPs and AgNO3were found to be in the range of 14-20mm for the test pathogens. Also the nanoparticle coated dressings showed antibacterial activity against the same, indicating its potential to control wound bio-burden and hence reduce the risk of further infection.