Biological synthesis of tellurium nanoparticles by isolated Brevibacillus sp. strain TR2211 as biocatalyst

<![CDATA[Tellurium nanoparticles have broad significant applications including treatment of infectious diseases, imaging, drug delivery systems, anti-inflammatory drug research, anti-inflammatory, anticoagulant drugs and treat many kinds of tumors. In the current study, potential of marine bacteria as biocatalysts were used for the biological reduction of tellurite oxyanion into to tellurium nanoparticles. The prepared tellurium nanoparticles were examined using UV-visible spectroscopy analysis, Energy dispersive x-ray spectroscopy EDS, Fourier-transform infrared spectroscopy FTIR and Scanning electron micrograph analysis. In this context, we isolated 13 tellurite-resistant bacteria were isolated using the enrichment technique. Among them, the strain TR2211 had a great potential for extracellular synthesis of tellurium nanoparticles. The isolated strain selected and characterized Brevibacillus sp. strain TR2211 GenBank accession number MK719235 based on phenotypic and molecular characteristics. Finally, the extracellular synthesis of tellurium nanoparticles was investigated under optimized reaction conditions. Our results show that the extracellular spherical-shaped tellurium nanoparticles with average size of 31 nm were formed in an optimal tellurite concentration of 1.5 mM, optimal initial biomass concentration 40 g/l at the optimal pH 7.5 and optimal temperature of 30ᵒ C after 120 h of incubation under resting cell conditions. This is the first report on biosynthesis of tellurium nanoparticles by Brevibacillus sp. strain TR2211. ]]>