Efficient nitrogen removal of a novel Pseudomonas chengduensis strain BF6 mainly through assimilation in the recirculating aquaculture systems

Biological nitrogen removal has received increasing attention in wastewater treatment. A bacterium with excellent nitrogen removal performance was isolated from biofilters of recirculating aquaculture systems (RAS) and identified as Pseudomonas chengduensis BF6. It was indicated that inorganic nitrogen is transformed into gaseous and biological nitrogen by the metabolic pathways of denitrification, anammox, and assimilation, which is the main nitrogen removal pathway of strain BF6. The strain BF6 could effectively remove nitrogen within 24 h under the conditions of ammonia, nitrate, nitrite, and mixed nitrogen sources with maximum total nitrogen removal efficiencies reaching 97.00 %, 61.40 %, 79.10 %, and 84.98 %, respectively. The strain BF6 exhibited total nitrogen removal efficiency of 91.14 %, altered the microbial diversity and enhanced the relative abundance of Pseudomonas in the RAS biofilter. These findings demonstrate that Pseudomonas sp. BF6 is a highly

Automated summary

A highly efficient bacterium, Pseudomonas chengduensis BF6, was isolated from biofilters of recirculating aquaculture systems (RAS) and found to be capable of removing nitrogen through denitrification, anammox, and assimilation pathways. The strain BF6 exhibited maximum total nitrogen removal efficiencies of 97.00%, 61.40%, 79.10%, and 84.98% for ammonia, nitrate, nitrite, and mixed nitrogen sources, respectively, within 24 hours. Furthermore, BF6 altered microbial diversity and increased the relative abundance of Pseudomonas in the RAS biofilter.