RNA-based spatial community analysis revealed intra-reactor variation and expanded collection of direct interspecies electron transfer microorganisms in anaerobic digestion. (February 2020)

• Record Type: Journal Article
• Authors: Guo, Bing; Zhang, Yingdi; Zhang, Lei; Zhou, Yun; Liu, Yang
• Is Part Of: Bioresource technology. Volume 298(2020)
• Publication Date: 2020-02
• Subjects: Anaerobic digestion -- Direct interspecies electron transfer (DIET) -- Community analysis -- 16S RNA analysis -- Low strength wastewater; Biomass -- Periodicals; Biomass energy -- Periodicals; Bioremediation -- Periodicals; Agricultural wastes -- Periodicals; Factory and trade waste -- Periodicals; Organic wastes -- Periodicals; Bioénergie -- Périodiques; Déchets agricoles -- Périodiques; Déchets industriels -- Périodiques; Déchets organiques -- Périodiques; Déchets (Combustible) -- Périodiques; 662.88
• DOI: 10.1016/j.biortech.2019.122534
• Languages: English
• ISSNs: 0960-8524

Abstract

Graphical abstract: Highlights: Fine spatial sampling revealed community variation along the height of sludge bed. Significantly different communities with and without GAC by RNA-based analysis. Active enrichments in complex GAC-biofilm expand potential DIET microorganisms. Bacteria Geobacter, Syntrophus, Desulfovibrio, and Blvii28 were enriched. Archaea Methanosaeta and Methanospirillum were enriched. Abstract: Granular activated carbon (GAC) has been shown to mediate direct interspecies electron transfer (DIET) in anaerobic digestion. Adding GAC to up-flow anaerobic sludge bed reactor increased the total biomass slightly from 20.0 to 26.6 gVSS/reactor, and maximum organic removal capacity remarkably from 285 to 1660 mgCOD/L/d. Since GAC occupied 7% of reactor volume (denser than suspended sludge, settled to the reactor bottom), we used a spatial sampling strategy (sludge bed top/mid/bottom layers, and tightly attached GAC-biofilm) and DNA- and RNA-based community analyses. RNA-based analysis demonstrated significant community differences between the non-GAC and GAC-amended reactors (p < 0.05) based on ANOSIM statistical analysis. In comparison, DNA-based analysis showed little community difference between these reactors (p > 0.05). RNA-based analysis revealed active enrichments in GAC-biofilm, including bacteria Geobacter, Syntrophus, Desulfovibrio and Blvii28, and archaea Methanosaeta and Methanospirillum . These are potential electro-active syntrophic microorganisms related with DIET, which expand the previously defined list of DIET microorganisms.