벤조피렌 분해균주와 자외선 조사의 병합처리를 통한 벤조피렌 분해력 증진

Abstract

To develop the effective and environment-friendly remediation method of PAHs contaminated in marine sediment, the degradation rate of Benzo[a]pyrene (BaP) and the Microtox toxicity of BaP degrading intermediates were evaluated by the combinatorial treatment of UV-C and BaP degrading bacteria, Novosphingobium pentaromativorans, using artificial sediment based on alumina particles coated with BaP. The degradation rates of BaP treated either by UV-C for one day or by bacterial inoculum for two days were 59% or 78% and the toxicities of remaining BaP and degrading intermediates were 32% or 12.5%, respectively. To enhance the degradation rate of BaP, UV-C and bacterial inoculation were combined. The first microcosm was treated by UV-C for one day followed by the inoculum for additional one day, while the second was treated by the reverse order. The degradation rates in these two microcosms were increased to 94.2 ~ 99.6% compared to that (78%) of inoculum only, moreover, the toxicities were reduced from 32% (UV treatment only) to 22 ~ 23.5%. Bacteria might reduce the toxic intermediates presumably derived from UV treatment. However, the survival rate of microorganism after the UV treatment was very low (< 2 cells ml-1) indicating that UV eliminated the bacteria also. These results imply that the sequent treatment of UV and microorganism could enhance the degradation rate of BaP and lower the toxicity through the decomposition of toxic intermediates. It could be applicable as one of the effective and environment-friendly methods for the remediation of PAHs contaminated in marine sediment.