Enhanced autotrophic denitrification under salinity stress by bioaugmentation of Sulfurimonas: performance evaluation, microbial community and response mechanisms

Liang Cui; Shasha Wang; Xiaxing Cao; Shicheng Chen; Jiannan Wang; Zhen Chen; Lijing Jiang; Xuezhe Wen; Wanpeng Wang; Qianqian Wang; Zhou Zhou; Suping Yang; Xuesong Yi; Yong Wang; Zongze Shao

doi:10.1016/j.biortech.2025.132971

Enhanced autotrophic denitrification under salinity stress by bioaugmentation of Sulfurimonas: performance evaluation, microbial community and response mechanisms

Bioresour Technol. 2025 Jul 11:132971. doi: 10.1016/j.biortech.2025.132971. Online ahead of print.

Authors

Liang Cui¹, Shasha Wang², Xiaxing Cao³, Shicheng Chen⁴, Jiannan Wang⁵, Zhen Chen⁶, Lijing Jiang⁷, Xuezhe Wen⁵, Wanpeng Wang⁸, Qianqian Wang⁹, Zhou Zhou¹⁰, Suping Yang¹¹, Xuesong Yi¹², Yong Wang¹³, Zongze Shao¹⁴

Affiliations

¹ State Key Laboratory Breeding Base of Marine Genetic Resources, Third Institute of Oceanography, MNR, Xiamen, PR China. Electronic address: cuiliang@tio.org.cn.
² State Key Laboratory Breeding Base of Marine Genetic Resources, Third Institute of Oceanography, MNR, Xiamen, PR China. Electronic address: wangshasha@tio.org.cn.
³ State Key Laboratory Breeding Base of Marine Genetic Resources, Third Institute of Oceanography, MNR, Xiamen, PR China. Electronic address: caoxiaxing@tio.org.cn.
⁴ Medical Laboratory Sciences Program, College of Health and Human Sciences, Northern Illinois University, DeKalb, USA.
⁵ State Key Laboratory Breeding Base of Marine Genetic Resources, Third Institute of Oceanography, MNR, Xiamen, PR China.
⁶ State Key Laboratory Breeding Base of Marine Genetic Resources, Third Institute of Oceanography, MNR, Xiamen, PR China. Electronic address: chenzhen@tio.org.cn.
⁷ State Key Laboratory Breeding Base of Marine Genetic Resources, Third Institute of Oceanography, MNR, Xiamen, PR China. Electronic address: Jianglijing@tio.org.cn.
⁸ State Key Laboratory Breeding Base of Marine Genetic Resources, Third Institute of Oceanography, MNR, Xiamen, PR China. Electronic address: wangwanpeng@tio.org.cn.
⁹ State Key Laboratory Breeding Base of Marine Genetic Resources, Third Institute of Oceanography, MNR, Xiamen, PR China. Electronic address: 238527196@fzu.edu.cn.
¹⁰ State Key Laboratory Breeding Base of Marine Genetic Resources, Third Institute of Oceanography, MNR, Xiamen, PR China. Electronic address: 22320231151532@stu.xmu.edu.cn.
¹¹ Department of Bioengineering and Biotechnology, Huaqiao University, Xiamen, PR China. Electronic address: yangsuping@hqu.edu.cn.
¹² School of Environmental Science and Engineering, Hainan University, Haikou, PR China.
¹³ State Key Laboratory Breeding Base of Marine Genetic Resources, Third Institute of Oceanography, MNR, Xiamen, PR China. Electronic address: wangyong@tio.org.cn.
¹⁴ State Key Laboratory Breeding Base of Marine Genetic Resources, Third Institute of Oceanography, MNR, Xiamen, PR China. Electronic address: shaozz@163.com.

PMID: 40653118
DOI: 10.1016/j.biortech.2025.132971

Abstract

Sulfur autotrophic denitrification (SADN) is a promising nitrogen removal process for industrial wastewater treatment, but elevated salinity is a common inhibitory factor that affects SADN performance. In this study, the sequencing batch biofilm reactor (SBBR) was enhanced with isolated salt-tolerant Sulfurimonas strains. Results showed that bioaugmentation improved the reactor's denitrification efficiency from 70.21 % to 98.79 %. As salinity increased from 1 % to 4 %, nitrogen removal efficiency experienced short fluctuations and quickly stabilized above 98.50 %. The abundance of Sulfurimonas increased from 13.06 % to 26.14 % with increasing salinity, becoming the most dominant taxon at high salinity. This genus maintained the highest abundance during sulfur disproportionation within the entire reactor. Network analysis indicated that Sulfurimonas primarily exhibited competitive relationships with other microbial groups. Additionally, there was a notable increase in gene abundance associated with denitrification and dissimilatory nitrate reduction. Overall, this study offers an efficient alternative method for nitrate removal in carbon-limited, high-salinity wastewater.

Keywords: Microbial community; Nitrate removal; Salinity; Sulfur autotrophic denitrification; Sulfurimonas.