Pyrene degradation by Pseudomonas sp and Burkholderia sp enriched from coking wastewater sludge

A pyrene-degrading consortium was enriched from sludge of coking wastewater treatment plant which included a combination of aerobic and anaerobic reactors. Biodegradation of pyrene by the consortium follows first-order kinetics. Addition of a co-substrate (glucose or anthraquinone) facilitated pyrene degrading. The highest degradation rate was achieved at 35 degrees C and pH 7.0, as glucose was added. In this case, pyrene (100 mg L-1) was degraded by 93.1 % within 36 h. An intermediate, 1-naphthol was detected via GC-MS analysis, indicating that pyrene degradation by the consortium proceeded with a pathway different from that associated with Mycobacterium sp. By comparisons of 16S rRNA gene sequences, two strains in this consortium were identified as Pseudomonas sp. and Burkholderia sp. The enriched pyrene-degrading consortium from coking wastewater treatment system shows highest pyrene-degrading activity compared with the reported pyrene degraders.