Biodegradation Characteristics and Bioaugmentation Potential of an Efficient O-Cresol-Degrading Strain Isolated from Petrochemical Sewage Treatment Plant
O-cresol and its isomers are one of the major pollutants to water environment. In this study, a highly effective o-cresol-degradation strain was isolated from the activated sludge of a petrochemical sewage treatment. Based on its morphology, physiological characteristics and 16S rDNA sequence analysis, it was identified as Pseudomonas sp. The optimal operating temperature, initial pH and rotary shaker speed for the strain to degrade o-cresol were experimentally determined to be 30°C,pH 6.5~8.0 and 150~200 rpm, respectively. Substrate scope experiment showed that the strain can degrade o-cresols other isomers and phenol. The degradation kinetics of the strain can be described by competitive substrate inhibition model with a maximum specific degradation rate of 0.055h-1. Furthermore, the bioaugmentation of the strain in the refinery wastewater to degrade o-cresol was investigated. The result showed that the strain is able to survive in refinery wastewater with high concentration of o-cresol and remove it efficiently.