Influence of trace erythromycin and erythromycin-H2O on microbial consortia in sequencing batch reactors (SBRs).

Abstract

The lack of knowledge on the roles of antibiotics and antibiotic resistance genes in the environment has hampered efforts to prevent and control the proliferation of antibiotic resistance. As such, there is a need to study antibiotic influence on WWTPs, the main collection pools of antibiotics and antibiotic resistance. To address this need, the influence of antibiotics ERY and its derivative ERY-H2O at ?g/L levels was studied on the micro-ecosystem of lab-scale SBRs, in terms of ecological function disturbance, resistance selection and phylogenetic structure alteration. The results revealed that at low concentrations, both ERY and ERY-H2O shared similar spectrums of sensitive bacteria and resistant bacteria. The enrichment of the resistant bacteria include those are capable of esterifying ERY via esterase ereA gene, as well as those are capable of forming biofilm and consequently enhanced the elimination of toxic nitrogenous substances. All these may offset the inhibitory effects of ERY and ERY-H2O on the SBR microorganisms.