Characterization of nitrous oxide reduction by Azospira sp. HJ23 isolated from advanced wastewater treatment sludge. Issue 12 (14th October 2020)

• Record Type: Journal Article
• Authors: Park, Hyung-Joo; Kwon, Ji Hyeon; Yun, Jeonghee; Cho, Kyung-Suk
• Is Part Of: Journal of environmental science and health. Volume 55:Issue 12(2020)
• Page Start: 1459
• Page End: 1467
• Publication Date: 2020-10-14
• Subjects: Nitrous oxide -- Azospira sp. -- denitrification -- functional denitrifying genes -- greenhouse gas; Environmental engineering -- Periodicals; Environmental sciences -- Periodicals; Ecology -- periodicals; Hazardous Substances -- periodicals; 628
• DOI: 10.1080/10934529.2020.1812321
• Languages: English
• ISSNs: 1093-4529

Abstract

Abstract: A new nitrous oxide (N2 O)-reducing bacterium was isolated from a consortium that was enriched using advanced wastewater treatment sludge as an inoculum and N2 O as the sole nitrogen source. The isolated facultative anaerobe was identified as Azospira sp. HJ23. Azospira sp. HJ23 exhibited optimum N2 O-reducing activity with a C/N ratio of 62 at pH 6 in the temperature range of 37 °C to 40 °C. The optimum carbon source for N2 O reduction was a mixture of glucose and acetate. The maximum rate of N2 O reduction by Azospira sp. HJ23 was 4.8 mmol·g-dry cell −1 ·h −1, and its N2 O-reducing activity was higher than other known N2 O reducers. Azospira sp. HJ23 possessed several functional genes for denitrification. These included narG (NO3 - reductase), nirK (NO2 - reductase), norB (NO reductase), and nosZ (N2 O reductase) genes. These results suggest that Azospira sp. HJ23 can be applied in the denitrification process to minimalize N2 O emission.