Biosynthesis of silver and selenium nanoparticles by Bacillus sp. JAPSK2 and evaluation of antimicrobial activity

The main aim of the present work was to evaluate the antibacterial activity of selenium and silver biogenic nanoparticles and further characterize them. The bacterial colony isolated from coal mine sample was found to reduce selenium and silver ions to their elemental forms respectively. Under experimental conditions, the isolated bacterium was capable of synthesising these nanoparticles which was indicated by the change in the colour of the medium to red for selenium and brown for silver. The effectiveness of these nanoparticles were tested against four clinical pathogens Escherichia coli, Klebsiella sp., Pseudomonas sp. and Staphylococcus aureus. The nanoparticles synthesised were then characterized by X-Ray diffraction analysis, Atomic Force Microscopy, UV-Vis analysis and Transmission Electron Microscopy. The sizes of these nanoparticles were also calibrated.