Characterization of bacterial diversity in wastewater of Indian paper industries with special reference to water quality

The bacterial diversity in terms of structure and community profile, with special reference to water quality in the wastewater treatment plant of Indian paper industries, is poorly understood. In the present work, characterization of bacterial diversity using 16S (V3-V4 region) rRNA gene amplicon sequencing data with reference to physicochemical parameters in the wastewater treatment plant of two paper industries has been carried out. Amplicon data analysis revealed the presence of bacterial taxa belonging to the phylum such as Bacteroidetes, Proteobacteria, Patescibacteria, Firmicutes, Actinobacteria, etc. Further, taxonomic classification upto genus level and functional analysis data indicated that genera such as Cloacibacterium, Aerococcus, Chryseobacterium, Microbacterium, Acinetobacter, Sphingobium, etc., were involved in the predicted metabolic pathways like carbohydrate metabolism, fatty acid and aromatic compounds biosynthesis as well as degradation. Canonical correspondence analysis confirmed a significant correlation between the microbial pollutions loads and physicochemical parameters. Further, the chemical oxygen demand, biochemical oxygen demand and total suspended solids exceeded the acceptable limits prescribed by Central Pollution Control Board New Delhi, Government of India, for discharge of wastewater. This study finds the correlation between the bacterial community residing in the polluted water of wastewater treatment plant and their environmental preferences. The presence of these bacterial diversity in the wastewater treatment plant of paper industries may affect the maintenance as well as paper quality. In future, it will provide a benchmark for the better understanding and management of wastewater treatment plant in paper industries across the globe.