Isolation of biphenyl-degrading microorganism and its cometabolic transformation of polychlorinated biphenyls (PCBs)

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.