Research article - Peer-reviewed, 2020
Effect of Cobalt, Nickel, and Selenium/Tungsten Deficiency on Mesophilic Anaerobic Digestion of Chemically Defined Soluble Organic Compounds
Safaric, Luka; Yekta, Sepehr Shakeri; Svensson, Bo H.; Schnurer, Anna; Bastviken, David; Bjorn, AnnikaAbstract
Trace elements (TEs) are vital for anaerobic digestion (AD), due to their role as cofactors in many key enzymes. The aim of this study was to evaluate the effects of specific TE deficiencies on mixed microbial communities during AD of soluble polymer-free substrates, thus focusing on AD after hydrolysis. Three mesophilic (37 degrees C) continuous stirred-tank biogas reactors were depleted either of Co, Ni, or a combination of Se and W, respectively, by discontinuing their supplementation. Ni and Se/W depletion led to changes in methane kinetics, linked to progressive volatile fatty acid (VFA) accumulation, eventually resulting in process failure. No significant changes occurred in the Co-depleted reactor, indicating that the amount of Co present in the substrate in absence of supplementation was sufficient to maintain process stability. Archaeal communities remained fairly stable independent of TE concentrations, while bacterial communities gradually changed with VFA accumulation in Ni- and Se-/W-depleted reactors. Despite this, the communities remained relatively similar between these two reactors, suggesting that the major shifts in composition likely occurred due to the accumulating VFAs. Overall, the results indicate that Ni and Se/W depletion primarily lead to slower metabolic activities of methanogenic archaea and their syntrophic partners, which then has a ripple effect throughout the microbial community due to a gradual accumulation of intermediate fermentation products.Keywords
artificial substrate; biogas; trace elements; micronutrients; volatile fatty acids; kineticsPublished in
Microorganisms2020, volume: 8, number: 4, article number: 598
Publisher: MDPI
Authors' information
Safaric, Luka
Linkoping Univ
Yekta, Sepehr Shakeri
Linkoping Univ
Svensson, Bo H.
Linkoping Univ
Swedish University of Agricultural Sciences, Department of Molecular Sciences
Linköping University
Bastviken, David
Linkoping Univ
Bjorn, Annika
Linkoping Univ
Associated SLU-program
Food Waste
UKÄ Subject classification
Microbiology
Publication Identifiers
DOI: https://doi.org/10.3390/microorganisms8040598
URI (permanent link to this page)
https://res.slu.se/id/publ/106424