BIODEGRADATION OF DIESEL ENGINE OIL BY MICROORGANISMS AND COMPARISON OF THEIR BIOREMEDIATION POTENTIAL: THE GRAVIMETRIC METHOD

Abstract

As the use of hydrocarbon fuels increases, the pollution of engine oil becomes one of the environmental problems. The rate of biodegradation of diesel fuel by microorganisms isolated from sewage (oil-contaminated soil) was studied. A reformed diesel fuel system was used and two major microorganisms isolated from the car parking lot - Micrococcus sp. and Pseudomonas sp. They were found to be hydrocarbon decomposers and two bacteria were selected for degradation tests. Diesel fuel degradation is estimated over a period of five to twenty-five days, using a gravimetric method. After 25 days of the fall season, Pseudomonas sp. reduce 67.57% of oil in Micrococcus sp. 52.95% today. But the mixture of Micrococcus sp. and Pseudomonas sp. was found to have high capacity to degrade diesel oil i.e. 89.98% after 25 days degradation rate of diesel oil by Micrococcus sp. The study found that it is 7.48 x 10-4gm / hr and that of Pseudomonas sp. was 9.55 x 10-4gm/hr while the combination of the two bacterial isolates showed the highest rate of diesel fuel degradation i.e. 1.27 x 10-3gm/h.