Enhanced chloramphenicol-degrading biofilm formation in microbial fuel cells through a novel synchronous acclimation strategy

Abstract

A novel synchronous acclimation strategy involving the continuous addition of sludge with chloramphenicol (CAP) was established to significantly enhance the formation of a highly efficient CAP-degrading anode biofilm in microbial fuel cells (MFCs). The highest power density of 414.00 mW/m2 and CAP-tolerant concentration of 80 mg/L were obtained from the synchronous MFC, which were 2.05 and 1.67 times higher than those from the control MFC, respectively. The unique loose and porous biofilm with high permeability and cell viability supported by interwoven cobweb-shaped proteins facilitated mass and electron transfer, primarily leading to the improvements. Additionally, more bi-functional bacteria for electricity generation and CAP degradation (e.g., Pseudomonas and Enterococcus) were specifically selected, and more beneficial mutualism occurred among the microbes in the biofilm during the synchronous acclimation process. This study provides a possibility to improve the long-term operation efficiency of antibiotic-degrading electrode biofilms for bioelectrochemical technology through the use of a simple and efficient acclimation strategy.