Lignin intermediates lead to phenyl acid formation and microbial community shifts in meso- and thermophilic batch reactors

Prem, Eva Maria (avtor), Mutschlechner, Mira (avtor), Stres, Blaž (avtor), Illmer, Paul (avtor), Wagner, Andreas Otto (avtor)

Background Lignin intermediates resulting from lignocellulose degradation have been suspected to hinder anaerobic mineralisation of organic materials to biogas. Phenyl acids like phenylacetate (PAA) are early detectable intermediates during anaerobic digestion (AD) of aromatic compounds. Studying the phenyl acid formation dynamics and concomitant microbial community shifts can help to understand the microbial interdependencies during AD of aromatic compounds and may be beneficial to counteract disturbances. Results The length of the aliphatic side chain and chemical structure of the benzene side group(s) had an influence on the methanogenic system. PAA, phenylpropionate (PPA), and phenylbutyrate (PBA) accumulations showed that the respective lignin intermediate was degraded but that there were metabolic restrictions as the phenyl acids were not effectively processed. Metagenomic analyses confirmed that mesophilic genera like Fastidiosipila or Syntrophomonas and thermophilic genera like Lactobacillus, Bacillus, Geobacillus, and Tissierella are associated with phenyl acid formation. Acetoclastic methanogenesis was prevalent in mesophilic samples at low and medium overload conditions, whereas Methanoculleus spp. dominated at high overload conditions when methane production was restricted. In medium carbon load reactors under thermophilic conditions, syntrophic acetate oxidation (SAO)-induced hydrogenotrophic methanogenesis was the most important process despite the fact that acetoclastic methanogenesis would thermodynamically be more favourable. As acetoclastic methanogens were restricted at medium and high overload conditions, syntrophic acetate oxidising bacteria and their hydrogenotrophic partners could step in for acetate consumption. Conclusions PAA, PPA, and PBA were early indicators for upcoming process failures. Acetoclastic methanogens were one of the first microorganisms to be impaired by aromatic compounds, and shifts to syntrophic acetate oxidation coupled to hydrogenotrophic methanogenesis occurred in thermophilic reactors. Previously assumed associations of specific meso- and thermophilic genera with anaerobic phenyl acid formation could be confirmed.

• Jezik: Angleški jezik
• Ključne besede: Bio-methane, Phenyl acids, Anaerobic digestion, Lignin intermediates, Amplicon sequencing
• Vrsta gradiva: Znanstveno delo
• Tipologija: 1.01 - Izvirni znanstveni članek
• Organizacija: FGG - Fakulteta za gradbeništvo in geodezijo
• Status publikacije: Objavljeno
• Različica publikacije: Objavljena publikacija
• Leto izida: 2021
• Št. strani: Str. 1-23
• Številčenje: ǂVol.ǂ14, art. 27
• PID: 20.500.12556/RUL-127114
• UDK: 591
• ISSN pri članku: 1754-6834
• DOI: 10.1186/s13068-020-01855-0
• COBISS.SI-ID: 48398851
• Datum objave v RUL: 18.05.2021

Gradivo je del revije

• Naslov: Biotechnology for biofuels
• Skrajšan naslov: Biotechnol. biofuels
• Založnik: BioMed Central
• ISSN: 1754-6834
• COBISS.SI-ID: 515780121

Sekundarni jezik

• Jezik: Slovenski jezik
• Ključne besede: mikrobiologija, lignin, bioplin, fenilna kislina