Archaeal community composition affects the function of anaerobic co-digesters in response to organic overload

Journal Article · Thu Mar 15 04:00:00 EDT 2012 · Waste Management

DOI:https://doi.org/10.1016/j.wasman.2011.11.013· OSTI ID:21612943

Lerm, S; Kleyboecker, A ^[1]; Miethling-Graff, R ^[1]; Alawi, M; Kasina, M; Liebrich, M ^[1]; Wuerdemann, H ^[1]

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1. International Centre for Geothermal Research (ICGR), GFZ German Research Centre for Geosciences, 14473 Potsdam (Germany)

Highlights: Black-Right-Pointing-Pointer Two types of methanogens are necessary to respond successfully to perturbation. Black-Right-Pointing-Pointer Diversity of methanogens correlates with the VFA concentration and methane yield. Black-Right-Pointing-Pointer Aggregates indicate tight spatial relationship between minerals and microorganisms. - Abstract: Microbial community diversity in two thermophilic laboratory-scale and three full-scale anaerobic co-digesters was analysed by genetic profiling based on PCR-amplified partial 16S rRNA genes. In parallel operated laboratory reactors a stepwise increase of the organic loading rate (OLR) resulted in a decrease of methane production and an accumulation of volatile fatty acids (VFAs). However, almost threefold different OLRs were necessary to inhibit the gas production in the reactors. During stable reactor performance, no significant differences in the bacterial community structures were detected, except for in the archaeal communities. Sequencing of archaeal PCR products revealed a dominance of the acetoclastic methanogen Methanosarcina thermophila, while hydrogenotrophic methanogens were of minor importance and differed additionally in their abundance between reactors. As a consequence of the perturbation, changes in bacterial and archaeal populations were observed. After organic overload, hydrogenotrophic methanogens (Methanospirillum hungatei and Methanoculleus receptaculi) became more dominant, especially in the reactor attributed by a higher OLR capacity. In addition, aggregates composed of mineral and organic layers formed during organic overload and indicated tight spatial relationships between minerals and microbial processes that may support de-acidification processes in over-acidified sludge. Comparative analyses of mesophilic stationary phase full-scale reactors additionally indicated a correlation between the diversity of methanogens and the VFA concentration combined with the methane yield. This study demonstrates that the coexistence of two types of methanogens, i.e. hydrogenotrophic and acetoclastic methanogens is necessary to respond successfully to perturbation and leads to stable process performance.

• OSTI ID: 21612943
• Journal Information: Waste Management, Journal Name: Waste Management Journal Issue: 3 Vol. 32; ISSN WAMAE2; ISSN 0956-053X
• Country of Publication: United States
• Language: English

Related Subjects

09 BIOMASS FUELS
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
60 APPLIED LIFE SCIENCES
ABUNDANCE
ALKANES
ANAEROBIC DIGESTION
BACTERIA
BIOCONVERSION
CARBOXYLIC ACIDS
DIGESTION
DISTURBANCES
GENE AMPLIFICATION
GENES
HYDROCARBONS
METHANE
MICROORGANISMS
MINERALS
ORGANIC ACIDS
ORGANIC COMPOUNDS
PERFORMANCE
POLYMERASE CHAIN REACTION
SLUDGES
VOLATILITY