Molecular biology techniques for the identification of microbial community in wastewater treatment reactors

Abstract Wastewater treatment has now become an important aspect worldwide with the increasing human population. Today, most wastewater treatment processes make use of the complex microbial communities for removing the contaminants. Microbial communities in wastewater treatment bioreactors have long been regarded as “black boxes.” Thorough understanding of the structure and properties, along with the function, of these complex communities is needed for scientists, researchers, and engineers working toward future plant optimization. Up to now, the understanding of microbial communities in the biological wastewater treatment reactors is insufficient due to the use of conventional techniques, which are time-consuming and involves laborious characterization experiments. However, the use of molecular biology techniques eliminates these limitations and provides benefits to microbial ecology research. Various molecular biology-based techniques have been used for analyzing the microbial community, including 16S rRNA cloning, denaturant gradient gel electrophoresis, fluorescent in situ hybridization, Dot-blot hybridization, real-time reverse transcription polymerase chain reaction, and next-generation sequencing techniques. These tools have promising potential for future applications to analyze the microbial diversity in the wastewater reactors. The techniques discussed in this chapter will expand our knowledge of the microbial diversity of biological wastewater treatment.