Biodegradation of used synthetic oil by hydrocarbon-degraders isolated from soil

Abstract

In this study, hydrocarbon degraders isolated from contaminated soil was studied for their potential as hydrocarbons biodegradation agents. The soil samples were retrieved from automotive workshop which has been exposed to constant contamination of synthetic engine oil. The morphology of strains was examined by using microscope to identify the isolated used synthetic oil degrading soil microorganism. Two strains capable of degrading used synthetic oil were isolated from the soil sample; Strain X and Y, which were spherical in shape and long, branching filamentous structure, respectively. Based on the observation, the morphology of Strain X and Strain Y were shown as cocci (bacteria) and hyphae (fungi) respectively. From the data collected, Strain Y showed a better growth compared to Strain X in broth. The toxicity of a range of used synthetic oil concentrations was tested by observing growth rate of Strain X because it showed better growth on M9 agar compared to Strain Y. The toxicity study showed that Strain X were able to grow, within the time of incubation, in all used synthetic oil concentrations except in medium amended with 5% used synthetic oil, where the growth was suboptimal. This study revealed that indigenous microorganisms isolated from contaminated soil were able to degrade used engine oil.