Effect of bioaugmentation on the microbial community and mono-digestion performance of Pennisetum hybrid

Li Lianhua; Li Ying; Sun Yongming; Yuan Zhenhong; Kang Xihui; Zhang Yi; Yang Gaixiu

doi:10.1016/j.wasman.2018.06.031

Effect of bioaugmentation on the microbial community and mono-digestion performance of Pennisetum hybrid

Waste Manag. 2018 Aug:78:741-749. doi: 10.1016/j.wasman.2018.06.031. Epub 2018 Jun 30.

Authors

Li Lianhua¹, Li Ying², Sun Yongming³, Yuan Zhenhong⁴, Kang Xihui¹, Zhang Yi¹, Yang Gaixiu²

Affiliations

¹ Guangzhou Institute of Energy Conversion, CAS Key Laboratory of Renewable Energy, Chinese Academy of Sciences, Guangzhou 510640, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China; Guangdong Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, PR China.
² Guangzhou Institute of Energy Conversion, CAS Key Laboratory of Renewable Energy, Chinese Academy of Sciences, Guangzhou 510640, PR China; Guangdong Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, PR China.
³ Guangzhou Institute of Energy Conversion, CAS Key Laboratory of Renewable Energy, Chinese Academy of Sciences, Guangzhou 510640, PR China; Guangdong Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, PR China. Electronic address: sunym@ms.giec.ac.cn.
⁴ Guangzhou Institute of Energy Conversion, CAS Key Laboratory of Renewable Energy, Chinese Academy of Sciences, Guangzhou 510640, PR China; Guangdong Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, PR China; Collaborative Innovation Centre of Biomass Energy, Henan Province, Zhengzhou 450002, PR China.

PMID: 32559966
DOI: 10.1016/j.wasman.2018.06.031

Abstract

In this study, bioaugmentation with methanogenic propionate-utilizing enrichment was investigated as a method to improve the mono-digestion performance of Pennisetum hybrid in a semi-continuous mode. The effect of bioaugmentation on the microbial community was analyzed as well. The results demonstrate that the steady-state organic loading rate (OLR) of the bioaugmented reactor increased to 4.0 g VS/(L·d) with a volumetric biogas production of 1.95 ± 0.17 m³/(m³·d). In contrast, the non-bioaugmented reactor failed at an OLR of 2.0 g VS/(L·d) accompanied with the accumulation of volatile fatty acids (VFAs). The results of whole genome pyrosequencing analysis suggest that the decrease in relative abundance of syntrophic butyrate and propionate oxidizers, such as Syntrophomonas, Syntrophobacter, and Syntrophorhabdus, reduced the conversion efficiency of butyrate and propionate which leads to the accumulation of butyrate and propionate, influencing the performance of the mono-digestion reactor. Conversely, in the bioaugmented reactor, the higher density of protein- and amino acid-utilizing bacteria, such as Proteiniphilum, Thermovirga, and Lutaonella, as well as the syntrophic association of Syntrophomonas spp. coupled with the methanogens Methanosarcina and Methanocella has a positive effect on system stability and performance.

Keywords: Bioaugmentation; Microorganism community; Mono-digestion; Pennisetum hybrid; Stability.