APPLICABILITY OF EVALUATING THE ABILITY OF MICROBES ISOLATED FROM AN OIL SPILL SITE TO DEGRADE OIL

Hydrocarbon-utilizing microorganisms were isolated byenrichment techniques from soil and water samples collectedfrom an oil spill site in the Niger delta area of Nigeria. Theisolates included species of {it Micrococcus, Pseudomonas,Bacillus, Aeromonas, Serratia, Proteus, Penicillium,Aspergillus, Candida, Geotrichum} and {it Rhizopus}. Oilbiodegradation potentials of the isolates were evaluated usingNigerian Forcados blend crude oil as sole carbon source inmineral salts medium. There were quantitative changes in theoil content due to microbial degradative activities.Degradation was more pronounced with mixed cultures than withsingle cultures of the microorganisms. The growth responses ofselected isolates to varying concentrations of crude oilshowed that while the growth of {it Pseudomonas, Micrococcus,Aspergillus} and {it Candida} species was not inhibited byincreasing concentrations of the crude oil, that of {itSerratia} and {it Rhizopus} was significantly ({it p} <0.05) suppressed.