title: Comparison of biogas sludge and raw crop material as source of hydrolytic cultures for anaerobic digestion.
abstract: Mixed fermentative/hydrolytic bacteria were enriched on lignocellulose substrates in minimal medium under semi-anaerobic mesophilic conditions in the presence or absence of natural zeolite as growth supporter to ultimately bioaugment non-adapted sludge and thereby enhance the overall anaerobic digestion (AD) of recalcitrant plant material. Desired enzyme activities, i.e. xylanases and cellulase were monitored during subsequent cultivation cycles. Furthermore, enriched microbial communities were characterized by 16S rRNA-based 454-Pyrosequencing, revealing Firmicutes, Bacteriodetes, Proteobacteria and Spirochaetes to be the predominant bacterial groups in cultures derived from anaerobic sludge and raw crop material, i.e. maple green cut and wheat straw as well. Enriched populations relevant for biopolymer hydrolysis were then compared in biological methane potential tests to demonstrate positive effects on the biogasification of renewable plant substrate material. A significant impact on methane productivity was observed with adapted mixed cultures when used in combination with clinoptilolite to augment and supplement non-adapted bioreactor sludge.
authors.affiliation: Austrian Centre of Industrial Biotechnology, Petersgasse 14/5, A-8010 Graz, Austria. Electronic address: stefan.weiss@acib.at.
authors.forename: Stefan
authors.initials: S
authors.lastname: Weiß
authors.affiliation: Engineering Consultant, Wiedner Hauptstrasse 90/2/19, A-1050 Vienna, Austria; IPUS Mineral- und Umwelttechnologie GmbH, Werksgasse 281, A-8786 Rottenmann, Austria.
authors.forename: Walter
authors.initials: W
authors.lastname: Somitsch
authors.affiliation: Medical University of Graz, Centre for Medical Research, Core Facility Molecular Biology, Stiftingtalstraße 24, A-8010 Graz, Austria.
authors.forename: Ingeborg
authors.initials: I
authors.lastname: Klymiuk
authors.affiliation: Medical University of Graz, Centre for Medical Research, Core Facility Computational Bioanalytics, Bioinformatics, Stiftingtalstraße 24, A-8010 Graz, Austria.
authors.forename: Slave
authors.initials: S
authors.lastname: Trajanoski
authors.affiliation: Austrian Centre of Industrial Biotechnology, Petersgasse 14/5, A-8010 Graz, Austria; University of Natural Resources and Life Sciences, Institute of Environmental Biotechnology, Konrad Lorenz Strasse 20, A-3430 Tulln, Austria.
authors.forename: Georg M
authors.initials: GM
authors.lastname: Guebitz
mesh_terms: D000693:Anaerobiosis; D001419:Bacteria / Q000235:genetics / Q000378:metabolism; D001673:Biodegradation, Environmental; D056804:Biofuels; D002480:Cellulase / Q000378:metabolism; D018556:Crops, Agricultural / Q000378:metabolism*; D006867:Hydrolases / Q000378:metabolism; D006868:Hydrolysis; D008697:Methane / Q000096:biosynthesis; D012336:RNA, Ribosomal, 16S; D012037:Refuse Disposal / Q000379:methods*; D012722:Sewage / Q000382:microbiology
chemical_list: D056804:Biofuels; D012336:RNA, Ribosomal, 16S; D012722:Sewage; D006867:Hydrolases; D002480:Cellulase; D008697:Methane
keywords: Bioaugmentation; Biogas; Green cut; Wheat straw; Zeolite