Arsenic Accumulation and Biosorption by Arsenic resistant Bacillus Subtilis isolated from the soil

Environmental contamination with heavy metals, especially arsenic (As) is one of the major problems in recent years. The present study demonstrates the effective removal and accumulation of arsenic by a soil bacterium called Bacillus subtilis strain A-7. The isolate was found to be highly resistant to arsenic with the Minimum Inhibitory Concentration value of 500 g/ml. The removal studies indicated a significant decrease in the metal concentration in the growth medium by the bacterium which was successfully adsorbed in the cell wall with the few parts accumulated inside the cells. The FTIR and SEM results reflected that the bacteria was quite active in quickly adsorbing the arsenic without any significant damage caused to the cells. This suggests the adsorption and accumulation efficiency of the Bacillus subtilis as the main mechanism in dealing with this toxic metalloid. Such arsenic resistant bacterium can be effectively applied for the bioremediation of contaminated soil and water.