16S193842NB

In this study, a negatively polarized graphite cathode accompanied with naturally occurring HSs (humic acid or humin) was applied to a dechlorinating culture enriched from marine sediment to enhance the dechlorination of the complex PCB mixture Aroclor 1260. The objectives of the study were to determine (1) whether cathode and humic redox mediators could increase the electron transfer efficiency and enhance the reductive dechlorination of Aroclor 1260, and (2) how does electric potential influence the abundance of potential PCB dechlorinators and their PCB reductive dehalogenase (RDase) genes in the cathodic biofilm and suspension culture. These findings address the knowledge gap regarding the microbial dechlorination characteristics and mechanism for commercial PCBs in BESs involving humic redox mediators. They can guide the application of BESs to sediments or HS-enriched environments for in situ PCB bioremediation.