Bioremediation By Bacillus Subtilis: Isolation, Molecular Characterization And Process Optimization
Abstract
Bioremediation is a green and viable practice that involves the use of microorganisms to break down pollutants in the environment instead of the use of chemicals as practiced in the conventional method. In the current research, a bacterial strain was isolated and the sewage water of Ezhakulam, Neyyattinkara and it was identified as Bacillus subtilis by morphological, biochemical, and molecular characterization. The isolate was highly proteolytic and had high potential of biodegrading methylene blue dye, a model pollutant. The efficiency of degradation peaked at 48 hours, then decreased, which could be explained by the fact that nutrients were used up, or by toxic intermediates that were formed.Optimization experiments proved that environmental conditions had a considerable effect on the efficiency of biodegradation. The highest percentage of dye removal occurred at 37°C with alkaline pH and 2 percent NaCl solution which increased the activity of the enzyme and dissolution of the pollutant. At optimized conditions the isolate had a maximum removal efficiency of which is compared to 32.76 when the conditions were normal. These results indicate the metabolic and environmental plasticity of Bacillus subtilis, such as the resistance to the extreme environment and the ability to generate various degradative enzymes.
In general, this paper shows that the Bacillus subtilis can be used as an effective bioremediation agent to treat wastewater. The findings also indicate the significance of maximization of physicochemical conditions to increase microbial degradation capacity and enable the use of bacterial systems in sustainable environmental management.
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