Performance, community dynamics and network of an aerobic denitrifying consortium from a coastal mariculture area

Abstract

Use of aerobic denitrifying consortia, as a new efficient tool for nitrogen removal, has attracted widespread attention because of their stable and efficient nitrogen removal ability. Yet, little attention has been given to highly efficient aerobic denitrifying consortia from mariculture environments. In this study, a natural aerobic denitrifying consortium, named C3, was obtained by an enrichment technique from a coastal mariculture area of Dongshan Bay of Fujian Province, China. In culture, it exhibited good and stable nitrate removing performance. Nitrogen mass balance indicated that 49.30% of the initial TN was converted into gaseous nitrogen and 49.63% was assimilated to biomass nitrogen. High-throughput sequencing and network analysis revealed that Pseudomonas and Fusarium were putative dominant aerobic denitrifying bacterial and fungal species, respectively, cooperating with Exophiala, Penicillium, Mortierella, Neocamarosporium, Neocosmospora, Sterigmatomyces, Thelebolus, Thermomyces, Cutaneotrichosporon and Gymnopilus to perform aerobic denitrification. In addition, four Pseudomonas strains have been successfully isolated from consortium C3, which supported the inference that Pseudomonas was the dominant contributor in the aerobic denitrifying consortium C3. These results will offer novel insights into aerobic denitrifying consortia in mariculture environments for biotechnological nitrogen pollution removal.