Background: With increasing demands of fossil fuel energy, extensive exploration of natural sources has caused a number of large scale accidental spills of crude oil and resulted in environmental disasters. The consequence of oil pollution to environment and human health has brought a serious challenge to environmental scientists. The aim of the present study is to evaluate the biodegradation of petrolum compound by Bacillus subtilis isolated from automobile workshops. Methods: Soil samples were collected from petrol bunks and workshops and subjected to serial dilution and plating. From the developed bacterial colonies, one was selected and identified as Bacillus subtilis based on the biochemical tests. The isolated strain was able to grow in minimal broth along with 2.5, 5, 7.5 and 10% concentrations of petrol which indicated the capability of the organism in degrading petrol and utilizing it as a source for growth. Results: The isolated strain's efficiency was determined by analysing the parameters pH, optical density and CO 2 released during petrol degradation. HPLC analysis also confirmed the degradation of petrol by Bacillus subtilis. Conclusion: The isolate Bacillus subtilis has the ability to tolerate the petrol concentrations and grow on them. Hence, this strain can be used in cleaning oil polluted sites.

The present study was conducted to determine the biodegradation of petrol by Pseudomonas aeruginosa isolated from petrol contaminated soil. The isolated strain was able to grow in minimal broth along with 2.5%, 5%, 7.5% and 10% concentrations of petrol which indicated the capability of the organism in degrading petrol and utilizing it as a source for growth. The isolated strain's efficiency was determined by analyzing the parameters pH, optical density and CO2 released during petrol degradation. High Performance Liquid Chromatography (HPLC) analysis also confirmed the degradation of petrol by Pseudomonas aeruginosa.