Publication

Abstract : Foxtail millet husk, an agro based waste material, presents a lucid opportunity as an unconventional source of silica due to its silica rich phytoliths. Sol–gel technique was employed to get silica supported copper and its calcination at 700 C led to the nanocomposite. XPS studies demonstrate that Cu²⁺ is the main species along with small amount of Cu⁰ in the nanocomposite. The evaluation of nanocomposite as a potential bactericidal agent was analyzed using the disk diffusion assay. Out of the nine bacterial stains, Staphylococcus aureus (gram positive) was the most susceptible to the nanocomposite. It was found that nanocomposite showed only moderate activity against gram negative strains. Interestingly, it was found to be inactive against Klebsiella pneumonia. The bactericidal activity of copper nanoparticles could be due to the enhanced surface area in the nanocomposite, increasing the adhesion of copper nanoparticles to the cell wall of the bacterium. Through a reduction mechanism, the nanoparticles cause disruption in enzyme activity, leading to the death of the bacterium.