Mixture of High Molecular Weight Polycyclic Aromatic Hydrocarbons Biodegradation by Tropical Bacteria and via Co-Metabolism with Phenanthrene

摘要

The experiment was conducted to evaluate the potential of tropical bacterial isolates and its consortium to biodegrade mixture of high molecular weight polycyclic aromatic hydrocarbons (chrysene, fluoranthene and pyrene). The effect of phenanthrene in the degradation was also investigated. The bacterial consortium was made up of Sphingomonas sp., Pseudomonas sp. And P. putida and biodegradation set up for 8 days with initial 100 mg L~(-1) substrate concentration. Degradation by Sphingomonas sp., Pseudomonas sp. And P. putida, respectively after 8 days gave higher residual chrysene of 40.2±1 .4,40.3±2.2 and 27.4±1.8 mg L~(-1), fluoranthene of 32.5±1.3, 35.4±1.2 and 10.1±2.5 mg L~(-1) and pyrene of 37.5±1.2, 34.2±2.4 and 32.0±1.2 mg L~(-1) compared to 11.5±1.4 (chrysene), 6.2±1.3 (fluoranthene) and 6.0±1.8 (pyrene) mg L~(-1) obtained using the bacterial consortium. When the media was supplemented with 100 mg L~(-1) phenanthrene, after 8 days of degradation by bacterial consortium residual chrysene, fluoranthene and pyrene was 0.45±0.25,0.02±0.02 and 0.20±0.14 mg L~(-1), respectively while phenanthrene was undetectable. No statistical significant (p < 0.05) difference was obtained between degradation by bacterial consortium and consortium via co-metabolism with phenanthrene rather they had a strong correlation of r = 0.99. The results suggest that bacterial consortium may be useful for the decontamination of sites polluted with high molecular weight polycyclic aromatic hydrocarbons due to synergistic effect.