Metagenomics analysis of microbial communities grown in constructed wetland-microbial fuel cell system treating sewage wastewater

Sewage wastewater poses a significant environmental threat, necessitating adequate treatment before disposal. This study investigates the microbial community structure and functional analysis involved in the treatment and detoxification of sewage wastewater using a constructed wetland integrated with microbial fuel cell system. High-throughput Illumina sequencing was employed to analyze microbial diversity. Sludge samples were collected from the root zone of Canna indica and the cathode samples for metagenomic profiling. Rarefaction curves and alpha diversity analysis demonstrated a higher abundance of microbial diversity in rhizospheric sludge sample comrated to cathodic sample. Taxonomic classification revealed Proteobacteria as the dominant phylum in the developed system. At the genus level, the sludge samples were dominated by uncultured bacterial genera. Notably, a substantial portion of the microbial community could not be identified at the genus and species levels, categorized as Unidentified. Functional profiling revealed the presence of genes associated with degradative pathways in sewage wastewater. These findings suggest that the rhizosphere of Canna indica supports a greater bacterial diversity than the cathode samples, contributing to the enhanced treatment efficiency of the developed system.