Abstract

Polychlorinated biphenyls (PCBs) are ubiquitous pollutions that cause public concern due to their long persistence, low degradability, strong bioaccumulation and high toxicity in the environment. A bacterium strain G-2 was isolated from an activated sludge of a chemical factory wastewater treatment plant in China. Based on its phenotypic typing coupled with 16S rRNA gene analysis, the strain was classified as Paracoccus sp. The strain G-2 can use biphenyl as sole carbon and energy sources, and almost complete degraded it within 7 days. Although this strain can only utilize 24% of PCB 77, more substrate may degrade when added biphenyl as cometabolic compound. The result may provide evidence for the potential application of Paracoccus in bioremediation of PCB-contaminated soil.

Key words: Polychlorinated biphenyls (PCBs), biphenyl, Paracoccus, cometablism.