Isolation, Identification and Characterization of Oil Degrading Bacteria Isolated from the Contaminated Sites of Barmer, Rajasthan

Petroleum refineries around the world have generated the solid wastes during the refining process and stocking of crude oil. Oily sludge leads to critical effects in the environment. The ecology of hydrocarbon degradation by microbial populations in the natural environment is reviewed, emphasizing the physical, chemical, and biological factors that contribute to the biodegradation of petroleum and individual hydrocarbons. Rate of biodegradation depends greatly on the composition, state, and concentration of the oil or hydrocarbons. Temperature and oxygen and nutrient concentrations are important variables in both types of environments. Salinity and pressure may also affect biodegradation rates in some aquatic environments, and moisture and pH may limit biodegradation in soils. Hydrocarbons are degraded primarily by bacteria and fungi. Adaptation by prior exposure of microbial communities to hydrocarbons increases hydrocarbon degradation rates. Therefore, in present research work attempts were made to isolate hydrocarbon degrading bacteria from the contaminated soil with petrol and diesel oil. 8 isolates were isolated and out of 8, 4 best isolates were selected for further studies. Biochemical screening of SP5, SP6, SP7 and SP8 were done. Simultaneously, antibiotic efficacy was also tested against tetracycline, ampicilline and oil degrading capacity with spectrophotometer analysis were performed. These screening showed in which 2 isolates SP5 and SP6 were positive and remaining SP7 and sp8 were gram negative. Isolates were tested with various biochemical tests. Antibiotic susceptibility tests were performed against tetracycline Nalinee Kumari et al 430 and ampicilline in which SP6 and SP7 were found to have more sensitivity against ampicilline and SP7 and SP8 were sensitive against tetracycline. The isolates were screened for their oil degrading capacity among them SP6 showed the best growth with oil as a sole source of carbon.