Biological treatment is currently a favorable option to treat wastewater due to its environmentally friendly methods and minimal toxic by-products. The majority of biological wastewater treatment uses bacteria as treatment agents, which are known to have excellent capabilities for removing various pollutants. Researchers have extensively explored the use of extracellular polymeric substances (EPSs) generated by bacteria in wastewater treatment. This review focuses on the sources of EPSs, factors influencing their production, and their role in wastewater treatment. Bacterial species, nutrient availability, pH, temperatures, and the presence of toxins were mentioned to be the factors influencing EPS production by bacteria in wastewater treatment. Produced EPSs by bacteria may promote the aggregation, adsorption, decolorization, and degradation of pollutants. This review highlights the challenges of discovering new potential bacterial species and complex EPS extraction methods, as well as the importance of mass production for larger-scale applications.

Hassimi Abu Hasan, Nurul Farhana Mohd Rahim, Jahira Alias, Jamilah Ahmad, Nor Sakinah Mohd Said, Nur Nadhirah Ramli, Junaidah Buhari, Siti Rozaimah Sheikh Abdullah, Ahmad Razi Othman, Hajjar Hartini Wan Jusoh, Hafizan Juahir, Setyo Budi Kurniawan