Synthesis of silver nanoparticles using Nigella sativa seed extracts and assessment of their antibacterial activity

Abstract

Silver nanoparticles were biosynthesized from Nigella sativa seed extracts using ethanol and chloroform. The antibacterial activity of silver nanoparticles against some drug-resistant bacteria has been established, but further study is needed to assess whether these particles could be an option for the treatment and prevention of drug-resistant microbial infections. Synthesized nanoparticles were characterized and screened for their antibacterial properties on resistant strains. The biosynthesized silver nanoparticles were characterized by UV-Visible, FTIR, Dynamic light scattering and Scanning Electron Microscope (SEM) analysis. The antibacterial action of biosynthesized silver nanoparticles was assessed by Microtitre Broth dilution process using Ciprofloxacin as standard, against resistant strains like Pseudomonas aeruginosa, Clostridium difficile, Klebsiella pneumoniae and Streptococcus pyogenes. The Silver nanoparticles obtained from chloroform extract of Nigella sativa seeds were more effective against Pseudomonas aeuruginosa, Clostridium difficile and Streptococcus pyogenes; than ethanolic seed extracts at 120 µL. Our data propose that the silver nanoparticles are effective against a variety of drug-resistant bacteria, which makes them a potential candidate for use in pharmaceutical products that may help to treat drug-resistant pathogens in different clinical environments. The present study focuses on the ability of phytoconstituents capped with silver nitrate can be used to treat infections caused by resistant bacteria