Ethanol-type anaerobic digestion enhanced methanogenic performance by stimulating direct interspecies electron transfer and interspecies hydrogen transfer

Shuang Zhang; Yuanyuan Ren; Pan Zhao; Xiaona Wang; Qunhui Wang; Xiaohong Sun

doi:10.1016/j.biortech.2024.131280

Ethanol-type anaerobic digestion enhanced methanogenic performance by stimulating direct interspecies electron transfer and interspecies hydrogen transfer

Bioresour Technol. 2024 Oct:410:131280. doi: 10.1016/j.biortech.2024.131280. Epub 2024 Aug 14.

Authors

Shuang Zhang¹, Yuanyuan Ren², Pan Zhao¹, Xiaona Wang², Qunhui Wang³, Xiaohong Sun⁴

Affiliations

¹ Department of Environmental Science and Engineering, School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China.
² Department of Environmental Science and Engineering, School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China; Beijing Key Laboratory on Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing 100083, China.
³ Department of Environmental Science and Engineering, School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China; Beijing Key Laboratory on Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing 100083, China. Electronic address: [email protected].
⁴ Beijing Agro-Biotechnology Research Center, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097, China.

PMID: 39151565
DOI: 10.1016/j.biortech.2024.131280

Abstract

Ethanol pre-fermentation of food waste effectively alleviates acidification; however, its effects on interspecies electron transfer remain unknown. This study configured the feed according to COD ratios of ethanol: sodium acetate: sodium propionate: sodium butyrate of 5:2:1.5:1.5 (ethanol-type anaerobic digestion) and 0:5:2.5:2.5 (control), and conducted semi-continuous anaerobic digestion (AD) experiments. The results showed that ethanol-type AD increased maximum tolerable organic loading rate (OLR) to 6.0 gCOD/L/d, and increased the methane production by 1.2-14.8 times compared to the control at OLRs of 1.0-5.0 gCOD/L/d. The abundance of the pilA gene, which was associated with direct interspecies electron transfer (DIET), increased by 5.6 times during ethanol-type AD. Hydrogenase genes related to interspecies hydrogen transfer (IHT), including hydA-B, hoxH-Y, hnd, ech, and ehb, were upregulated during ethanol-type AD. Ethanol-type AD improved methanogenic performance and enhanced microbial metabolism by stimulating DIET and IHT.

Keywords: E-pili; Ethanol-type fermentation; Hydrogenase genes; Methane production; Syntrophic metabolism.

MeSH terms

Anaerobiosis
Bioreactors
Electron Transport
Ethanol* / metabolism
Fermentation
Hydrogen* / metabolism
Hydrogenase / metabolism
Methane* / metabolism

Substances

Methane
Hydrogen
Ethanol
Hydrogenase