Accumulation of lead (Pb II) metal ions by Bacillus toyonensis SCE1 species, innate to industrial-area ground water and nanoparticle synthesis

Groundwater samples were collected from Peenya Industrial area of Bengaluru, India to check its inherent bacterial population. After the isolates were grown in lead-induced media, the bacteria that could resist lead were further isolated, identified, and grown. The isolated bacterium was identified as Bacillus toyonensis SCE1 species, and the maximum amount of lead taken up by it to sustain itself as a live biomass was 8 ppm. Lead accumulation was studied based on different factors such as pH, concentration, and time. Bacterial characterization through scanning electron microscopy showed there was lead sorption on the bacterial cells. Transmission electron microscopy revealed that accumulated lead ions inside the bacteria were in the range of 180–190 nm, this was found to correlate with the data obtained by the particle size analyzer. The optimum pH for highest lead accumulation was 7.2, for a time period of 160 min. It was observed that the stable production of homogenous nanoparticles using biomass could be achieved by optimizing factors such as incubation period, agitation, pH, temperature, and contact time.