Antimicrobial Activity of Bacterial Community for Removal of Pathogens during Vermifiltration

Abstract

The present study brings insight to the antimicrobial activity of isolated bacterial species in a vermifilter (VF) during the combined treatment of domestic wastewater and organic fraction of municipal solid waste (OFMSW). The study showed that vermifilter resulted in an effluent with biochemical oxygen demand (BOD) <20 mg/L and coliforms<103 MPN/100 mL, signifying higher treatment and pathogen removal efficacy. A total of 41 colony forming units (CFU) were isolated, out of which 12 strains were selected, which exhibited higher antimicrobial activity against pathogenic bacteria and fungi. This observation indicated the existence of a mechanism responsible for removal of pathogens, and based on comparative sequence analysis of 16S rRNA genes, the characterized bacterial strains could be subdivided into two phylogenetic clusters: Firmicutes and γ-Proteobacteria. These findings suggested that identified strains contribute to the search for new sources of antimicrobial substances and enhancing the disinfection efficiency during wastewater treatment by vermifiltration.