Dataset Information

Anoxic Biodegradation of Isosaccharinic Acids at Alkaline pH by Natural Microbial Communities.

ABSTRACT: One design concept for the long-term management of the UK's intermediate level radioactive wastes (ILW) is disposal to a cementitious geological disposal facility (GDF). Under the alkaline (10.013.0) anoxic conditions expected within a GDF, cellulosic wastes will undergo chemical hydrolysis. The resulting cellulose degradation products (CDP) are dominated by ?- and ?-isosaccharinic acids (ISA), which present an organic carbon source that may enable subsequent microbial colonisation of a GDF. Microcosms established from neutral, near-surface sediments demonstrated complete ISA degradation under methanogenic conditions up to pH 10.0. Degradation decreased as pH increased, with ?-ISA fermentation more heavily influenced than ?-ISA. This reduction in degradation rate was accompanied by a shift in microbial population away from organisms related to Clostridium sporosphaeroides to a more diverse Clostridial community. The increase in pH to 10.0 saw an increase in detection of Alcaligenes aquatilis and a dominance of hydrogenotrophic methanogens within the Archaeal population. Methane was generated up to pH 10.0 with acetate accumulation at higher pH values reflecting a reduced detection of acetoclastic methanogens. An increase in pH to 11.0 resulted in the accumulation of ISA, the absence of methanogenesis and the loss of biomass from the system. This study is the first to demonstrate methanogenesis from ISA by near surface microbial communities not previously exposed to these compounds up to and including pH 10.0.

SUBMITTER: Rout SP

PROVIDER: S-EPMC4569480 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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Anoxic Biodegradation of Isosaccharinic Acids at Alkaline pH by Natural Microbial Communities.

Rout Simon P SP Charles Christopher J CJ Doulgeris Charalampos C McCarthy Alan J AJ Rooks Dave J DJ Loughnane J Paul JP Laws Andrew P AP Humphreys Paul N PN

PloS one 20150914 9

One design concept for the long-term management of the UK's intermediate level radioactive wastes (ILW) is disposal to a cementitious geological disposal facility (GDF). Under the alkaline (10.0<pH>13.0) anoxic conditions expected within a GDF, cellulosic wastes will undergo chemical hydrolysis. The resulting cellulose degradation products (CDP) are dominated by α- and β-isosaccharinic acids (ISA), which present an organic carbon source that may enable subsequent microbial colonisation of a GDF. ...[more]

PMID: 26367005

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Dataset Information

Anoxic Biodegradation of Isosaccharinic Acids at Alkaline pH by Natural Microbial Communities.

Publications

Anoxic Biodegradation of Isosaccharinic Acids at Alkaline pH by Natural Microbial Communities.

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