Microbial community analysis in waste water treatment system and determination of biodegradation potentials of these communities

Within the scope of the study, two different types of wastewater treatment plants, namely municipal and industrial wastewater treatment plants, were seasonally sampled and 40 samples were taken from different operational units. Measurements such as pH, biological oxygen demand, elemental analysis and mesophilic bacteria counts were performed on the samples. Culture-dependent and culture-independent experiments were designed to determine the microbial diversity in the wastewater treatment plants. Culture-dependent studies have been carried out to investigate the microorganisms that degrade the phenol in the plants. As culture-independent methods,to elucidate the microbial diversity of the environment in detail, fluorescence in situ hybridization (FISH) experiments were performed and the 16S rRNA V3-V4 gene regions were amplified by PCR and sequenced with Illumina MiSeq and Roche 454 GS FLX + / Junior platforms. The obtained data were analyzed using QIIME and ChunLab CL Community programs. The results of the elemental analyzes indicated that the elemental values of the different units of the two plants were different and that the pH values are fixed in the aeration tanks and variable in the other units. It has been determined that isolates isolated in culture dependent studies and capable of phenol degrade are generally Pseudomonas species. 16S rRNA amplicon sequencing assays performed to study microbial populations within culture-independent studies have determined that the composition of the resulting plants changes with the sampling period. Furthermore, the taxonomic composition of municipal and industrial wastewater treatment plants is also very different. The result of FISH analysis was also extensively determined for Bacteria domain members in all samples. Keywords: Wastewater, FISH (Fluorescence In Situ Hybridization), biodegradation, phenol, microbial diversity