Intermolecular interaction between microbial extracellular polymeric substances (EPS) and contaminants during biological wastewater treatment process

Abstract

Biological treatment is one of the most widely used wastewater treatment processes. Microbial extracellular polymeric substances (EPS), a complex high-molecular compound, are usually produced by microorganisms during their metabolic process in wastewater treatment. EPS on the surface of the microbial cells govern the microbial surface properties and play crucial roles in the transfer and removal of hazardous contaminants from wastewater. Previous work showed that EPS adsorbed heavy metal ions and organic pollutants due to the presence of abundant functional groups. Moreover, EPS could also bound with nutrients (e.g., N, P) through hydrogen bonds. In addition, the redox activities of EPS were reported, which could change the form of various contaminants in wastewater. Therefore, EPS may play key roles in biological wastewater treatment process and greatly influence the reduction and transformation of various contaminants. Thus, developing novel analytical methods with high sensitivity is useful to better understand the intermolecular interactions between EPS and various contaminants, which have great guiding significance on elucidating the removal mechanism of different contaminants in biological wastewater treatment process.