Novel intertidal wetland sediment-inoculated moving bed biofilm reactor treating high-salinity wastewater: Metagenomic sequencing revealing key functional microorganisms

• Published in: Bioresource technology 2022-03, Vol.348, p.126817-126817, Article 126817
• Main Authors: Zhang, Haifeng, Wu, Jiahua, Li, Ruifeng, Kim, Dong-Hoon, Bi, Xuejun, Zhang, Guoli, Jiang, Bo, Yong Ng, How, Shi, Xueqing
• Format: Article
• Language: English
• Subjects: Biofilms; Bioreactors; DNA pyrosequencing; High salinity; Intertidal wetland sediment; Metagenomic sequencing; Moving bed biofilm reactor; Nitrogen - analysis; Salinity; Waste Disposal, Fluid; Waste Water; Wetlands
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2022.126817

[Display omitted] •Novel IWS-inoculated MBBR assessed for treating high salinity wastewater.•Superior performance (especially nitrogen removal) in IWS-inoculated MBBR observed.•Correlation between microbial dominance and their metabolic contribution analyzed.•Metagenomic sequencing exhibited possible nitrogen metabolic pathways.•Potential of IWS for wastewater treatment revealed by function enzyme screening. In this study, two lab-scale moving bed biofilm reactors (MBBR), seeded with intertidal wetland sediment (IWS) and activated sludge (AS), were constructed to compare their performances in treating high-salinity (3%) wastewater. Under a wide range of influent TOC (178–620 mg/L) and NH4+-N (25–100 mg/L), both the MBBRs (Riws and Ras) exhibited excellent TOC removal efficiencies of >95%. Regarding nitrogen reduction, Riws exhibited a significantly superior TN removal efficiency of 90.2 ± 1.8% than that of Ras (76.8 ± 2.9%). A correlation analysis was innovatively conducted comparing the results between metagenomic sequencing and DNA pyrosequencing, and positive linear relationships were found with R2 values of 0.763–0.945. Meanwhile, for illustration of different TN removal performance, nitrogen metabolic pathways were also assessed. Moreover, a list of functional oxidases (EC: 1.13.11.1, EC: 1.13.11.2, EC: 1.13.11.24, EC: 1.13.12.16, EC: 1.4.3.4, EC: 1.16.3.3, EC: 1.14.14.28) was found in IWS, revealing its potential in degradation of recalcitrant organics.