Synergistic removal of emerging contaminants using bacterial augmented floating treatment bed system (FTBs) of Typha latifolia and Canna indica for rejuvenation of polluted river water

The bacterial augmented FTBs consisting wet plants achieved reduction of 57%, 70%, 74%, and 80% in biochemical oxygen demand (BOD), chemical oxygen demand (COD), total phosphate, and sulfate, respectively. Moreover, the 16S <i>rRNA</i> gene amplicon sequencing identified <i>Proteobacteria</i> as the dominant phylum, with <i>Pseudomonas</i> species and <i>Hydrogenophaga</i> species being the most abundant genera in FTBs containing <i>T. latifolia</i> and <i>C. indica</i>, respectively. The functional gene prediction indicated presence of various xenobiotic degrading genes too. Non-targeted LC-HRMS analysis of treated water demonstrated complete elimination of antibiotic derivatives and dye intermediates, along with the partial removal of pharmaceutical and personal care products (PPCPs) and chemical intermediates. Additionally, the abundance of probable pathogenic bacteria and dominant antibiotic resistance genes was significantly reduced upon treatment. The phytotoxicity analysis of the treated water supported the outcomes. The studies on removal of emerging contaminants in the polluted river ecosystem has been relatively less explored, highlighting novelty and future possible applications of the plant-microbial augmented FTBs in rejuvenation of polluted rivers.