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A strain of Pseudomonas aeruginosa isolated from a polluted soil was found to produce an extracellular bioemulsifier when cultivated on hexadecane as sole carbon source. The emulsifier was precipitated with acetone and redissolved in sterile water. Dodecane, crude oil and kerosene were found to be good substrates for emulsification by the bioemulsifier. Growth and bioemulsifier production reached the optimal levels on the fourth and fifth day, respectively. Emulsifying activity was observed over a pH range of 3.5 to 10.0 with a maximum at pH 7.0. The activity of the bioemulsifier was heat stable up to 70 °C while about 50 percent of its activity was retained at 100 °C. The components of the bioemulsifier were determined, it was found to contain carbohydrate, protein and lipid. The protein complex was precipitated with ammonium sulphate and fractionated on a Sephadex G-100. Gel electrophoresis of the bioemulsifier showed a single band whose molecular weight was estimated as 14,322 Da. The bioemulsifier was classified as a peptidoglycolipid. Certain strains of P. aeruginosa produce peptidoglycolipid in place of rhamnolipid

Four bacteria, identified as Pseudomonas aeruginosa, Alcaligenes eutrophus, Bacillus subtilis and Micrococcus'luteus were isolated from crude oil polluted soils using anthracene as the sole carbon and energy source. All the organisms utilized n-hexadecane, n-tetradecane, diesel oil, engine oil and naphthalene as sole carbon sources. None could utilize hexane, cycloheptane, xylene, benzene, toluene, phenol, fluoranthene,and kerosene as carbon sources. Highest cell density obtained with 0.1% (w/v) anthracene were 4.5 × 107(cfu/ml), 8.6 × 106(cfu/ml), 5.4 × 106and 2.4 × 106(cfu/ml) respectively, for P. aeruginosa, A. eutrophus, B. subtilis and M. luteus after 30 days incubation. Growth of the organism s on a Nigerian crude oil resulted in a residual oil concentration of 22.2% , 33.3% , 39.3% ,44% and 91.7% respectively, for P. aeruginosa, A. eutrophus, B. subtilis, M. luteus and the noninoculated control on the 14 th day. Ring fission enzymes of the meta pathway were detected in induced cells of P. aeruginosa and A. eutrophus while ortho pathway enzymes were detected in B. subtilis and M. luteus. P. aeruginosa and A. eutrophus had specific catechol-2,3-dioxygenase activities of 3.8 ± 0.183 and 0.64 ± 0.032 µmol / min × mg protein respectively while catechol-1,2-dioxygenase activities of 1.95 ± 0.029 and 1.89 ± 0.026 µmol / min x mg protein were detected in B. subtilis and M. luteus respectively. This work , highlights the capability of these unreported tropical strains of A. eutrophus, B. subtilis and M. luteus as anthracene degraders.