Screening of BDE-47 Degrading Bacteria and Optimization of Improving Recovery Rate During the Degradation Process
-
Graphical Abstract
-
Abstract
Three acclimation methods including the gradient pollutant concentration acclimation, maximum contaminant level acclimation and external carbon source assisted acclimation were compared to optimize the screening efficiency of BDE-47 high efficiency degradation strains or flora. In addition, physical and chemical demulsifying methods were used and compared to enhance the recovery rate of liquid-liquid extraction that was negatively affected by emulsification caused by bacterial surface hydrophobicity and secretion of extracellular products. Results showed that a maximum amount of 14 strains that were able to feed on BDE-47 as the sole carbon source were finally obtained when the single strain was first isolated followed with progressive acclimation, while the acclimation and isolation step were sequentially reversed, only 7, 3 and 11 strains were screened, and all of these strains can be found corresponding strains in the 14 strains by morphological observation, respectively. The combination of bath, centrifugal and methanol interaction demulsification process was optimal demulsification, and the recovery rate could be as high as 92.3%. NaC1 throughout the demulsification process for recovery of BDE-47 played a negative role, while the use of methanol played a positive one.
-
-