title: Green synthesis and structural characterization of selenium nanoparticles and assessment of their antimicrobial property.
abstract: In the present study, selenium nanoparticles were biologically synthesized by non-pathogenic, economic and easy to handle bacterium Ralstonia eutropha. The selenium oxo anion was reduced to selenium nanoparticles in the presence of the bacterium. The bacterium was grown aerobically in the reaction mixture. An extracellular, stable, uniform, spherical selenium nanoparticle was biosynthesized. The TEM analysis revealed that the biosynthesized selenium nanoparticles were spherical in shape with size range of 40-120 nm. XRD and SAED analysis showed that nanocrystalline selenium of pure hexagonal phase was synthesized. The formation of actinomorphic trigonal selenium nanorods was also observed. A mechanism of biosynthesis of selenium nanoparticles by R. eutropha was proposed. The biosynthesized selenium nanoparticles were investigated for their antimicrobial activity against potential pathogens. Selenium nanoparticles showed excellent antimicrobial activity. The 100, 100, 250 and 100 µg/ml selenium nanoparticles were found to inhibit 99 % growth of Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli and Streptococcus pyogenes, respectively. Similarly, the 500 µg/ml of selenium nanoparticles was found to inhibit the growth of pathogenic fungi Aspergillus clavatus. The antimicrobial efficacy of selenium nanoparticle was comparable with commercially available antibiotic drug Ampicillin.
authors.affiliation: Department of Chemical Engineering, Sardar Vallabhbhai National Institute of Technology, Surat, 395007, Gujarat, India.
authors.forename: Nishant
authors.initials: N
authors.lastname: Srivastava
authors.forename: Mausumi
authors.initials: M
authors.lastname: Mukhopadhyay
mesh_terms: D000890:Anti-Infective Agents / Q000008:administration & dosage / Q000138:chemical synthesis; D002470:Cell Survival / Q000187:drug effects / Q000502:physiology; D020118:Cupriavidus necator / Q000187:drug effects* / Q000502:physiology; D055772:Green Chemistry Technology / Q000379:methods*; D008422:Materials Testing; D053768:Metal Nanoparticles / Q000008:administration & dosage* / Q000737:chemistry* / Q000648:ultrastructure; D010316:Particle Size; D012643:Selenium / Q000008:administration & dosage* / Q000737:chemistry*
chemical_list: D000890:Anti-Infective Agents; D012643:Selenium