Isolation And Identification Of Crude Oil Degrading Bacteria From Soil Polluted With Automobile Lubricants

Oil spillage is a big problem in most industries especially in developing countries and it contaminates soil and water. Microorganisms can be used to remediate crude oil contaminated sites through bioremediation. Bioremediation is preferred to other methods of decontamination of polluted soil because these other methods lead to production of toxic compounds and are non-economic.

The aim of this study was to isolate and identify crude oil degrading bacteria from soil polluted with automobile lubricants, determine their rate of crude oil utilization and select the best degraders. Oil contaminated soil samples were collected from Mechanic village, Nsukka. The isolation was done using Bushnell Haas broth, Bushnell Haas agar with a vapour phase transfer technique to allow only the growth of bacteria that use hydrocarbon from kerosene carbon source and nutrient agar.

The isolates were identified using different biochemical tests and morphological analysis. Spectrophotometric analysis was carried out to determine the optical densities of the isolates in order to obtain the rate of crude oil utilization by the microorganisms and to select the best degraders. It was determined that these strains belong to the bacteria genera of Micrococcus and Streptomyces and they displayed the highest capability for biodegradation of crude oil. Hence, these bacteria genera can be used for bioremediation of crude oil contaminated sites.