Degradation of phenanthrene by bacterial strain isolated from soil in oil refinery fields in Shanghai China.

A bacterial strain Pseudomonas stutzeri ZP2 was identified with phenanthrene-degrading ability based on Gram staining, oxydase reaction, biochemical tests, FAME analysis, G+C content and 16S rDNA gene sequence analysis. It is the first time that P. stutzeri is reported to process the capability for phenanthrene degradation. The strain was isolated from soil samples contaminated with polycyclic aromatic hydrocarbon (PAH)-containing waste from an oil refinery field in Shanghai, China. Strain P sp. ZP2 can utilize naphthalene, phenanthrene and Tween 80 as its sole carbon source and can degrade phenanthrene very fast, 6 days for 96% phenanthrene at 250 ppm concentration. The optimal growth conditions of strain ZP2 was determined to be at pH 8.0, 37 degrees C, respectively. The results also indicate that strain ZP2 can remove more than 90% of phenanthrene at any concentrations ranged from 250 to 1000 ppm in 6 days. It suggests that strain ZP2 can endure high concentrations of phenanthrene. Besides, the effects of non-ionic surfactants such as Brij 30, Triton X100 and Tween 80, on the phenanthrene degradation were examined. Therefore, this strain may find great application in bioremediation practices.