Deeper insight into the effect of salinity on the relationship of enzymatic activity, microbial community and key metabolic pathway during the anaerobic digestion of high strength organic wastewater

Yijang Yin; Zengshuai Zhang; Kunlun Yang; Peng Gu; Shiguang Liu; Yifan Jia; Zhaochang Zhang; Tao Wang; Jianqi Yin; Hengfeng Miao

doi:10.1016/j.biortech.2022.127978

Deeper insight into the effect of salinity on the relationship of enzymatic activity, microbial community and key metabolic pathway during the anaerobic digestion of high strength organic wastewater

Bioresour Technol. 2022 Nov:363:127978. doi: 10.1016/j.biortech.2022.127978. Epub 2022 Sep 17.

Authors

Yijang Yin¹, Zengshuai Zhang², Kunlun Yang², Peng Gu², Shiguang Liu¹, Yifan Jia¹, Zhaochang Zhang¹, Tao Wang³, Jianqi Yin⁴, Hengfeng Miao⁵

Affiliations

¹ School of Environmental and Civil Engineering, Jiangnan University, Wuxi 214122, PR China.
² School of Environmental and Civil Engineering, Jiangnan University, Wuxi 214122, PR China; Jiangsu Key Laboratory of Anaerobic Biotechnology, Jiangnan University, Wuxi 214122, PR China; Jiangsu Engineering Laboratory of Biomass Energy and Carbon Reduction Technology, Jiangnan University, Wuxi 214122, PR China.
³ School of Environment Engineering, Wuxi University, Wuxi 214105, PR China.
⁴ Department of Earth and Environmental Engineering, Columbia University, New York, NY 10027, USA.
⁵ School of Environmental and Civil Engineering, Jiangnan University, Wuxi 214122, PR China; Jiangsu Key Laboratory of Anaerobic Biotechnology, Jiangnan University, Wuxi 214122, PR China; Jiangsu Engineering Laboratory of Biomass Energy and Carbon Reduction Technology, Jiangnan University, Wuxi 214122, PR China; Water Treatment Technology and Material Innovation Center, Suzhou University of Science and Technology, Suzhou 215009, PR China. Electronic address: hfmiao@jiangnan.edu.cn.

PMID: 36126846
DOI: 10.1016/j.biortech.2022.127978

Abstract

The threshold salt concentration to inhibit the anaerobic digestion (AD) has been intensively investigated, but its insight mechanism is not fully revealed. Therefore, this study systematically investigated the effect of salinity on acidogenesis and methanogenesis and its mechanism. Results showed that low salinity level (i.e. 0.6%) had stimulatory effect on volatile fatty acids (VFA) and methane production, while significant inhibition was observed with further increased salinity. Moreover, high salinity limited the butyric acid degradation at acidogenesis process. The decreases of enzymes (AK and PTA) activity and functional genes (ackA, pta and ACOX) expression that related to β-oxidation explained the butyric acid accumulation at high salinity levels. Microbial community analysis revealed high salinity levels significantly inhibited the proliferation of Syntrophomonas sp., which are known to be associated with butyric acid degradation. Similarly, the relative abundance of acetoclastic methanogen (Methanothrix sp.) and methylotrophic methanogen (Methanolinea sp.) significantly decreased at salinity condition.

Keywords: Anaerobic digestion; Enzyme activity; Functional genes; Microbial communities; Salinity.

MeSH terms

Anaerobiosis
Bioreactors
Butyrates
Fatty Acids, Volatile
Metabolic Networks and Pathways
Methane / metabolism
Microbiota* / genetics
Salinity
Sewage
Wastewater*

Substances

Butyrates
Fatty Acids, Volatile
Sewage
Waste Water
Methane