title: Co-digestion of wheat and rye bread suspensions with source-sorted municipal biowaste.
abstract: Acidification of wheat bread (WBS), rye bread (RBS) and fresh biowaste suspensions (FBS), leading to lactate+acetate, lactate+acetate+n-buyrate, and acetate+propionate+n-butyrate, respectively, and biogas production as well as population dynamics were investigated. Co-fermentation of FBS (14 kg m(-3) d(-1) organic loading rate (OLR)) with WBS or RBS was stable up to an OLR of 22 kg m(-3) d(-1) and resulted in up to 3 times as much biogas. During co-fermentation at more than 20 kg m(-3) d(-1) OLR the total population increased more than 2-fold, but the originally low share of propionate-oxidizing bacteria significantly decreased. The proportion of methanogens also decreased. Whereas the proportion of Methanosarcinales to Methanomicrobiales in biowaste and biowaste+WBS remained constant, Methanosarcinales and in particular Methanosaeta spec. in the biowaste+RBS assay almost completely disappeared. Methanomicrobiales increased instead, indicating propionate oxidation via acetate cleavage to CO2 and hydrogen.
authors.affiliation: Karlsruhe Institute of Technology (KIT), Institute of Biology for Engineers and Biotechnology of Wastewater, Am Fasanengarten, D-76128 Karlsruhe, Germany. Electronic address: Chaoran.Li3@kit.edu.
authors.forename: Chaoran
authors.initials: C
authors.lastname: Li
authors.affiliation: Karlsruhe Institute of Technology (KIT), Institute of Biology for Engineers and Biotechnology of Wastewater, Am Fasanengarten, D-76128 Karlsruhe, Germany. Electronic address: Christoph.Moertelmaier@kit.edu.
authors.forename: Christoph
authors.initials: C
authors.lastname: Mörtelmaier
authors.affiliation: Karlsruhe Institute of Technology (KIT), Institute of Biology for Engineers and Biotechnology of Wastewater, Am Fasanengarten, D-76128 Karlsruhe, Germany. Electronic address: Josef.Winter@kit.edu.
authors.forename: Josef
authors.initials: J
authors.lastname: Winter
authors.affiliation: Karlsruhe Institute of Technology (KIT), Institute of Biology for Engineers and Biotechnology of Wastewater, Am Fasanengarten, D-76128 Karlsruhe, Germany; University of Applied Science, Hochschule Emden-Leer, Faculty of Technology, Division Microbiology - Biotechnology, Constantiaplatz 4, D-26723 Emden, Germany. Electronic address: Claudia.Gallert@HS-Emden-Leer.de.
authors.forename: Claudia
authors.initials: C
authors.lastname: Gallert
mesh_terms: D001673:Biodegradation, Environmental; D056804:Biofuels; D019149:Bioreactors / Q000382:microbiology*; D001939:Bread; D002245:Carbon Dioxide / Q000737:chemistry; D002947:Cities; D000068016:Eubacteriales; D020564:Deltaproteobacteria; D005227:Fatty Acids / Q000737:chemistry; D005285:Fermentation; D006859:Hydrogen / Q000737:chemistry; D008697:Methane / Q000737:chemistry; D019640:Methanosarcinales; D012037:Refuse Disposal / Q000379:methods*; D012434:Secale / Q000737:chemistry* / Q000382:microbiology*; D013535:Suspensions; D014908:Triticum / Q000737:chemistry* / Q000382:microbiology*
chemical_list: D056804:Biofuels; D005227:Fatty Acids; D013535:Suspensions; D002245:Carbon Dioxide; D006859:Hydrogen; D008697:Methane
keywords: Biowaste suspensions; Co-digestion; Microbial community changes; Rye or wheat bread suspensions