Simultaneous removal of antibiotic-resistant bacteria and its resistance genes in water by plasma oxidation: Highlights the effects of inorganic ions

Antibiotic-resistant bacteria (ARB) and their resistance genes (ARGs), which are commonly detected in waters, are emerging environmental contaminants with strong pathogenicity. Simultaneous removal of ARB and ARGs in water by mesoporous plasma was explored in this study, focusing on evaluating the impacts of common inorganic ions on ARB inactivation, antibiotic resistance reduction, and change in ARGs profiles. The antibiotic resistant Escherichia coli (AR E. coli) was selected as the model ARB. The experimental results demonstrated that the presence of NO3-, Cu2+, and Fe2+ all promoted ARE. coli inactivation and ARGs elimination, reduced its antibiotic resistance, and also inhibited horizontal gene transfer of ARGs; whereas CO32- inhibited these processes, and SO42- did not have distinct effect. During the plasma treatment process, Fe2+ significant enhancement on (OH)-O-center dot formation via reactions with H2O, the highest performance was observed in the presence of Fe2+. The membrane structure, disruption of biological processes, dissolution of intracellular components, and DNA. These finding shed light on the potential effects of inorganic ions on ARB and ARGs elimination induced by the mesoporous plasma.