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[Display omitted] • The Mn redox cycle removed 94.67 % of E2 within 12 h (0.079 mg L−1h−1). • Interaction of reactive oxygen species and Mn(III) accelerated E2 removal. • Bioreactor showed 89.63% of NO 3 −-N and 97.57% of 17β-estradiol removal efficiency. • Community assembly enhanced the metabolic and physiological activity of bioreactor. • Different elemental cycles in the community were coupled with contaminant removal. The application of bio-manganese (Mn) redox cycling for continuous removal of contaminants provides promise for addressing coexisting contaminants in groundwater, however, the feasibility of constructing Mn redox cycling system (MCS) through community assembly remains to be elucidated. In this study, Mn-reducing strain MFG10 and Mn-oxidizing strain MFQ7 synergistically removed 94.67 % of 17β-estradiol (E2) within 12 h. Analysis of potential variations in Mn oxides suggested that MCS accelerated the production of reactive oxygen species (ROS) and Mn(III), which interacted to promote E2 removal. After continuous operation of the Mn ore-based immobilized bioreactor for 270 days, the experimental group (EG) achieved average removal efficiencies of 89.63 % and 97.57 % for NO 3 −-N and E2, respectively. High-throughput sequencing results revealed complex symbiotic relationships in EG. Community assembly significantly enhanced the metabolic and physiological activity of the bioreactor, which promoting the expression of core functions including nitrogen metabolism, Mn cycling and organic matter resistance. [ABSTRACT FROM AUTHOR]

[Display omitted] • A bibliometric analysis of Mn redox cycling coupled with nitrogen removal was conducted. • Mechanisms and influencing factors of Mn redox coupled nitrogen removal were discussed. • Application of Mn redox-driven nitrogen removal in sewage treatment was summarized. • Research gaps, challenges, and directions for future development were proposed. Nitrogen (N) pollution has emerged as one of the major threat to global sustainable development and has received increasing attention. Manganese (Mn) is the third most abundant transition metal on earth and microbially mediated Mn redox cycling coupled with N removal (MMnRCCNR) is a promising alternative that is not only economical and efficient but also has a low environmental impact. This review discusses the key influencing factors, theoretical basis, and mechanisms of Mn species as key mediators driving the biogeochemical cycle. In addition, the application and development trend of Mn redox cycling in the treatment of polluted water are summarized and presented, especially the combination of simultaneous N and micropollutant removal. The research hotspots and trends of Mn redox cycling mediated biological N removal are analyzed by bibliometric methods and the current research gaps, challenges, and future directions are identified. Overall, this review is expected to provide guide for further development and optimization of Mn redox-mediated microbial N removal processes, which will help to develop cost-effective N removal processes in the future to treat contaminated water. [ABSTRACT FROM AUTHOR]