Effect of a Profound Feedstock Change on the Structure and Performance of Biogas Microbiomes

Abstract

In this study the response of biogas-producing microbiomes to a profound feedstock change was investigated. The microbiomes were adapted to the digestion of either 100% sugar beet, maize silage, or of the silages with elevated amounts of total ammonium nitrogen (TAN) by adding ammonium carbonate or animal manure. The feedstock exchange resulted in a short-range decrease or increase in the biogas yields according to the level of chemical feedstock complexity. Fifteen taxa were found in all reactors and can be considered as generalists. Thirteen taxa were detected in the reactors operated with low TAN and six in the reactors with high TAN concentration. Taxa assigned to the phylum Bacteroidetes and to the order Spirochaetales increased with the exchange to sugar beet silage, indicating an affinity to easily degradable compounds. The recorded TAN-sensitive taxa (phylum Cloacimonetes) showed no specific affinity to maize or sugar beet silage. The archaeal community remained unchanged. The reported findings showed a smooth adaptation of the microbial communities, without a profound negative impact on the overall biogas production indicating that the two feedstocks, sugar beet and maize silage, potentially do not contain chemical compounds that are difficult to handle during anaerobic digestion.

Co‐substrate composition is critical for enrichment of functional key species and for process efficiency during biogas production from cattle manure

“…Members within this phylum are proposed to have the capacity to use both amino acids and carbohydrates and to perform propionate oxidation (Johnson & Hug, 2022 ; Westerholm et al, 2022 ). In previous studies on biogas processes, this phylum has been suggested as a biomarker for process disturbance (Klang et al, 2019 , 2020 ; Singh, 2021 ; Singh, Moestedt, et al, 2021 ; Singh, Müller, & Schnürer, 2021 ). In the present study, the reduced abundance of families belonging to phylum Ca .…”

High-resolution monitoring of VFA dynamics reveals process failure and exponential decrease of biogas production

“…3b). Klang et al [31] tested the effects of changing environments (e.g., exchanging sugar beet silage for maize silage and vice versa) on the biogas microbiomes. While the archaeal communities did not change during their 8-week test phase after the feedstock change, the bacterial communities adapted.…”

“…The degradation of propionic acid into educts for methane formation (acetate, formate, or hydrogen) is characterized by an unfavorable thermodynamic balance. Thus, this reaction is only possible when the cleavage products are directly used further by acid-degrading methanogens and require a close syntrophic relationship between both groups of microorganisms [31,[34][35][36]. The presence of acetateproducing bacteria (using H 2 and CO 2 ) also leads to favorable thermodynamics as H 2 partial pressure is kept low [37].…”

Functional conservation of microbial communities determines composition predictability in anaerobic digestion

“…The feedstock addition could be well controlled to be the same and periodical across the AD process. Due to these advantages, AD has been used as a model system to understand microbial community assembly under changes in feedstock or sludge properties [9,10], reveal microbial community assemblage differences among replicated reactors [11], and predict digestor performance based on operational parameters [12]. These advantages of the AD system provide a unique opportunity to address the above questions and hypotheses (Fig.…”