Ammonia Oxidizing Bacteria in Wastewater Treatment

Abstract

Wastewater pollutants such as trace organic chemicals and pharmaceutical compounds pose a major threat to aquatic environments and human health. There is a critical need to develop potential strategies that aim at enhancing the metabolism and/or cometabolism of these compounds. Ammonia oxidation is critical to global nitrogen cycling and is often driven by ammonia-oxidizing bacteria. Ammonia-oxidizing bacteria (AOB) transform ammonium to nitrite, an essential step in the complete mineralization of organic matter, thereby leading to the accumulation of nitrate in oxic environments. Enhanced pollutant degradation by ammonia oxidizing bacteria (AOB) has been widely observed in wastewater treatment processes. This chapter discusses the recent progress in the ecophysiology of AOB and outlines the current knowledge related to the biodegradation efficiencies of the frequently reported wastewater pollutants by AOB. The aerobic biodegradation mechanism and kinetics of pollutant removal along with the biodegraded products and pathways of these compounds have been identified and summarized in this chapter. Moreover, to increase the sustained cometabolic biodegradation of pollutants, potential strategies such as microorganism diversity (AOB and heterotrophs), chemical structure and redox potentials, physicochemical properties and operational parameters, activated sludge and membrane-based processes have been elaborately discussed. Taken together, this chapter effectively illustrates the progress, current achievements and future recommendations in the application of AOB towards wastewater pollutant treatment, which can present new insights to the researchers and engineers working in this field.