Abstract

Boboye, B., Olukunle, O. F.*, and Adetuyi, F. C.

A study was carried out to isolate hydrocarbon -degrading bacteria associated with environmental samples collected from Ilaje coastal area, Nigeria. The samples were analyzed microbiologically using standard microbiological techniques. These organisms were further studied to determine their biodegrading activities on hydrocarbons (diesel, kerosene, petrol) using enrichment medium. The microbial growths were determined using spectrophotometer blanked at 600 nm. The nine bacteria isolated from environmental samples were Enterobacter aerogenes, Pseudomonas aeroginosa, Aerococcus viridian, Clostridium sporogenes, Staphylococcus aureus, Lactobacillus acidophilus, Micrococcus luteus, Streptococcus faecalis and Bacillus sp. It was observed from the result that the length of incubation had significant effect on degradation as well as the cell load. For all the bacteria, there was general increase in length of incubation with the various hydrocarbons. The results showed that there was degradation of oil, mostly between days 1 and 3. It was also observed that there was a gradual decline in the concentration of the broth, between days 4 and 7, which suggests decrease in the bacterial population and that the oil was being degraded. The test on the degrading activity of isolates on hydrocarbon revealed that S. aureus, C. sporogenes, S. faecalis and Bacillus sp. were the best degraders of kerosene, petrol and diesel, respectively. The ability of these isolates to degrade hydrocarbons is clear evidence that their genome harbors the relevant degrading gene. However, an important limiting factor is the slow rate of degradation which often limits the practicality of using microorganisms in remediating hydrocarbon impacted environment. Further research in this area can make a marked improvement.