Heterotrophic nitrification and aerobic denitrification by a novel Acinetobacter sp. ND7 isolated from municipal activated sludge

• Published in: Bioresource technology Vol. 301; p. 122749
• Main Authors: Xia, Lin, Li, Xiaomin, Fan, Wenhong, Wang, Jianlong
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.04.2020
• Subjects: Acinetobacter; Acinetobacter sp; activated sludge; Aerobiosis; ammonium; Ammonium Compounds; ammonium nitrogen; Denitrification; Heterotrophic nitrification-aerobic denitrification; Heterotrophic Processes; nitrate nitrogen; Nitrification; nitrite nitrogen; Nitrites; Nitrogen; Nitrogen removal; phenotype; Phylogeny; Sewage; technology; temperature; wastewater; Wastewater treatment; Nitrogen removal; Acinetobacter sp; Wastewater treatment; Heterotrophic nitrification-aerobic denitrification
• ISSN: 0960-8524; 1873-2976; 1873-2976
• DOI: 10.1016/j.biortech.2020.122749

[Display omitted] •A novel strain of Acinetobacter sp. ND7 was isolated and identified.•ND7 had efficient capability for heterotrophic nitrification and aerobic denitrification.•The functional genes hao, napA and nirS were successfully amplified by PCR.•ND7 has significant potential for application for nitrogen removal from wastewater. A novel strain was isolated from municipal activated sludge and identified as Acinetobacter sp. ND7 based on its phenotypic and phylogenetic characteristics, which had efficient capability for heterotrophic nitrification and aerobic denitrification. Strain ND7 could remove approximately 99.8% of ammonium-N (51.0 mg/L), 96.2% of nitrite-N (51.8 mg/L) and 97.18% of nitrate-N (52.1 mg/L), with the maximum specific removal rate of 5.74, 4.17 and 3.63 mg/(L h), respectively. Ammonium was manifested to be utilized preferentially during simultaneous nitrification and denitrification. The functional genes hao, napA and nirS were successfully amplified by PCR, further evidencing the heterotrophic nitrification and aerobic denitrification capability of Acinetobacter sp. ND7. The optimal conditions for nitrogen removal were temperature of 35 °C, C/N ratio of 8. Acinetobacter sp. ND7 displays superior performance for nitrogen removal, with no nitrite accumulation under aerobic condition, and thus has significant potential for practical application for nitrogen removal from wastewater.