Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
6306753 | Chemosphere | 2016 | 9 Pages |
â¢Pseudomonas aeruginosa was capable of removing Cr(VI) and degrading BDE-47.â¢BDE-47 degradation rate varied with different concentrations of Cr(VI).â¢Cr(VI) removal was improved in the presence of low concentrations of BDE-47.â¢Characteristics of bacterial cells changed due to concomitant BDE-47/Cr(VI).
Simultaneous Cr(VI) removal and 2,2â²,4,4â²-tetra brominated diphenyl ether (BDE-47) biodegradation by Pseudomonas aeruginosa in liquid medium were investigated in this study, with the goal of elucidating the interaction between concomitant pollutants Cr(VI) and BDE-47 during microbial remediation. The experimental results revealed that the degradation efficiency of 1 mg Lâ1 BDE-47 by 60 mg Lâ1 biomass achieved 51.3% within 7 d when 2 mg Lâ1 Cr(VI) coexisted. The degradation efficiency was accelerated at low concentrations of Cr(VI) (â¤5 mg Lâ1), but inhibited at higher levels (â¥10 mg Lâ1). Cr(VI) of 2 mg Lâ1 facilitated the secretion of rhamnolipid from the strain, altered cell surface hydrophobicity and cell membrane permeability, and promoted intracellular BDE-47 accumulation, thus improving BDE-47 biotransformation. In addition, the stimulation of intracellular enzyme synthesis by 2 mg Lâ1 Cr(VI) contributed to more BDE-47 elimination in the cells. The achievement of BDE-47 biodegradation was coupled with cell growth, enzyme extraction, cell membrane permeability change, and ATPase activity increase. The study also indicated that the improvement of Cr(VI) removal in BDE-47/Cr(VI) co-contaminated condition was mostly due to the increasing synthesis of extracellular enzyme in the presence of low concentrations of BDE-47. The whole study demonstrated that P. aeruginosa was available for the removal of toxic Cr(VI) and degradation of BDE-47 simultaneously in the liquid.