Biosorption of some Heavy Metals by Metal Resistant Bacillus thuringiensis Isolated from Soil in Basra Governorate- Iraq

Abstract

In present study heavy metal resistant bacteria were isolated from soil collected from Fao district in Basra governorate South of Iraq.  On the basis of morphological, biochemical, 16S rRNA gene sequencing and phylogeny analysis revealed that, the isolates were authentically identified as Bacillus thuringiensis. The minimal inhibitory concentration (MIC) of isolates against cadmium (Cd) and lead (Pb) was determined on solid medium. B. thuringiensis showed significant resistance to high concentrations of Pb (1800 mg/l) and Cd (50 mg/l). The biosorption capabilities of B. thuringiensis for Cd and Pb were monitored at different ion concentrations and contact times. The functional groups of bacterial surface were determined using Fourier transform infrared, and X-ray powder diffraction analysis.

Key Words: Bacillus thuringiensis, Minimal Inhibitory Concentration, Biosorption, Fourier transform infrared, X-ray powder diffraction