Performance evaluation, enzymatic activity change and metagenomic analysis of sequencing batch reactor under divalent zinc stress

Yuqiao Zhang; Weiyi Qi; Guangyu Chu; Qianzhi Wang; Chang Gao; Wenzheng Chen; Jiateng Liu; Mengchun Gao

doi:10.1016/j.biortech.2023.129774

Performance evaluation, enzymatic activity change and metagenomic analysis of sequencing batch reactor under divalent zinc stress

Bioresour Technol. 2023 Nov:388:129774. doi: 10.1016/j.biortech.2023.129774. Epub 2023 Sep 16.

Authors

Yuqiao Zhang¹, Weiyi Qi², Guangyu Chu², Qianzhi Wang², Chang Gao³, Wenzheng Chen³, Jiateng Liu³, Mengchun Gao⁴

Affiliations

¹ Key Lab of Marine Environment and Ecology, Ministry of Education, Ocean University of China, Qingdao 266100, China; Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering, Qingdao 266100, China.
² Key Lab of Marine Environment and Ecology, Ministry of Education, Ocean University of China, Qingdao 266100, China; College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China.
³ Key Lab of Marine Environment and Ecology, Ministry of Education, Ocean University of China, Qingdao 266100, China.
⁴ Key Lab of Marine Environment and Ecology, Ministry of Education, Ocean University of China, Qingdao 266100, China; Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering, Qingdao 266100, China. Electronic address: mengchungao@outlook.com.

PMID: 37722545
DOI: 10.1016/j.biortech.2023.129774

Abstract

Divalent zinc (Zn²⁺) are widely detected in domestic and industrial wastewater, and it is essential to evaluate the effect of Zn²⁺ on wastewater biological treatment process due to its bio-toxicity. In this study, the nitrogen removal rates and their corresponding enzymatic activities of sequencing batch reactor decreased with the increase of Zn²⁺ concentration. The Zn²⁺ accumulation in activated sludge caused significant antioxidant response, and the reactive oxygen species (ROS) production and antioxidant enzymatic activities were positively correlated with Zn²⁺ concentration. The presence of Zn²⁺ inhibited the metabolic pathways related to energy production and electron transport. The abundance decreases of nitrification and denitrification functional genes led to the deterioration of nitrogen removal performance under Zn²⁺ stress. The correlation analysis between functional gene modules and microbial genera revealed that Zoogloea had obvious Zn²⁺ resistance. This study can provide the insights into the influencing mechanism of Zn²⁺ on the biological nitrogen removal process.

Keywords: Antioxidant response; Divalent zinc; Functional genes; Nitrogen metabolism; Sequencing batch reactor.