Isolation and characterization of a new Pseudomonas-related strain capable of degradation of phenol from oil contaminated soil

Abstract

A novel phenol-degrading bacterium named as SKDP-1 was isolated from crude oil contaminated soil, Gudao oil field in the Northeast of Shandong Dongying, East China. The biochemical tests indicated that strain SKDP-1 was Gram-negative, and glucose and citrate could be utilized and starch not gelatin. Both Voges-Proskauer and H₂O₂ enzyme tests were positive. The activities of catechol 1,2-dioxygenase (C12O) and catechol 2,3-dioxygenase (C23O) in free cells were measured to be 8 and 91 IU, respectively. 16S rDNA gene sequences of strain SKDP-1 analysis showed the similarity of 98% with Pseudomonas putida (）AB680847). The phylogenetic tree formed by 16S rDNA sequences from both strain SKDP-1 and its most related bacteria also proved strain SKDP-1 to be one member of the genus Pseudomonas. Strain SKDP-1 showed the high phenol-degrading rates from 30 to 99% cultured by mineral salts medium (MSM), which was added with phenol from 100 to 1600 mg/L, respectively. The optimum pH and growth temperature for strain SKDP-1 to remove phenol were about 7.0 and 30°C, respectively. Based on its biochemical properties and high capability of degrading phenol, strain SKDP-1 provided the possibilities of treating phenol contaminated environment in the future.

Keywords: Phenol degradation, Pseudomonas, ortho-cleavage pathway

African Journal of Biotechnology, Vol 13(14), 1560-1566