Phylogenetic Analysis of Anaerobic Co-Digestion of Animal Manure and Corn Stover Reveals Linkages between Bacterial Communities and Digestion Performance

Abstract

Over 3 million tons of manures are produced annually in the United States and pose environmental and health risks if not remediated. Anaerobic digestion is an effective method in treating organic wastes to reduce environmental impacts and produce methane as an alternative energy. Previous studies suggested that optimization of feed composition, hydraulic retention time, and other operational conditions can greatly improve total solids removal and increase methane productivity. These environmental factors improve functionality by altering the microbial community structure but explicit details of how the bacterial community shifts are poorly understood. Our investigations were conducted to investigate the relationship between environmental factors, microbial community structure and bioreactor efficiency by using metagenomic analysis of the microbial communities. Our results indicated that the bioreactor with the greatest methane production, digestion efficiency and reduced levels of E. coli/Shigella had a distinctive community structure at the genus level with unique and abundant uncultivated strains of Bacteroidetes. Moreover the same bioreactor was enriched in Aminomonas paucivorans and Clostridia populations that can utilize secondary metabolites produced during cellulose/hemicellulose degradation to generate hydrogen and acetate. Hence specific digestion conditions that enrich for these populations may provide a route to the optimization of co-digestion systems and control the variability in reactor performance.

A Review of the Role of Critical Parameters in the Design and Operation of Biogas Production Plants

“…This also validates the fact that many current digesters are designed in a multistaged manner so that acidogenesis and methanogenesis are technically separated into two different volumes allowing each group of microorganisms to operate at optimal conditions [207]. The correlation between the different bacterial species and different levels of HRT has been studied and depicted in a recent paper by Yang et al [208].…”

Microbial assemblages and methanogenesis pathways impact methane production and foaming in manure deep-pit storages

“…Intriguingly, Clostridia were positively correlated with Methanomicrobia and Methanobacteria in both no-foam and crust-forming manure, respectively, while Bacteroidia were positively correlated with unclassified Archaea in foaming manure. While members of both Clostridia and Bacteroidia are known hydrogen producers that support methanogenesis, a high abundance of Bacteroidia has previously been found in high methane-producing anaerobic bioreactors [55][56][57]. The synergistic interactions between bacteria and methanogens could explain the uniquely high MPR observed in the foaming manure, despite hydrogenotrophic methanogenesis being the main methane-producing pathway in all manure storage pits in the study.…”

Enhancement of Bioelectrochemical CO2 Reduction with a Carbon Brush Electrode via Direct Electron Transfer

“…While extracellular electron transfer has not been detected in Tangfeifania , a closely related strain, Prolixibacter denitrificans , can accept electrons from zero valent-iron , Similar to Tangfeifania , extracellular electron transfer has not been documented in Aminomonas . However, some of its close relatives can reduce extracellular electron acceptors such as elemental sulfur .…”

“…35 Aminomonas species are amino acid fermenters that can grow in syntrophic association with Methanobacterium species and have also been detected in anaerobic digester systems. 36,37 Similar to Tangfeifania, extracellular electron transfer has not been documented in Aminomonas. However, some of its close relatives can reduce extracellular electron acceptors such as elemental sulfur.…”