| Title: | Metabolic and microbial community dynamics during the anaerobic digestion of maize silage in a two-phase process |
| Author(s): | Strauber H; Lucas R; Kleinsteuber S; |
| Address: | "Department of Environmental Microbiology, Helmholtz Centre for Environmental Research (UFZ), Permoserstr. 15, 04318, Leipzig, Germany. heike.straeuber@ufz.de. Department of Environmental Microbiology, Helmholtz Centre for Environmental Research (UFZ), Permoserstr. 15, 04318, Leipzig, Germany" |
| Journal Title: | Appl Microbiol Biotechnol |
| DOI: | 10.1007/s00253-015-6996-0 |
| ISSN/ISBN: | 1432-0614 (Electronic) 0175-7598 (Linking) |
| Abstract: | "Two-phasic anaerobic digestion processes (hydrolysis/acidogenesis separated from acetogenesis/methanogenesis) can be used for biogas production on demand or a combined chemicals/bioenergy production. For an effective process control, detailed knowledge about the microbial catalysts and their correlation to process conditions is crucial. In this study, maize silage was digested in a two-phase process and interrelationships between process parameters and microbial communities were revealed. In the first-phase reactor, alternating metabolic periods were observed which emerged independently from the feeding frequency. During the L-period, up to 11.8 g L(-1) lactic acid was produced which significantly correlated to lactic acid bacteria of the genus Lactobacillus as the most abundant community members. During the alternating G-period, the production of volatile fatty acids (up to 5.3, 4.0 and 3.1 g L(-1) for propionic, n-butyric and n-caproic acid, respectively) dominated accompanied by a high gas production containing up to 28 % hydrogen. The relative abundance of various Clostridiales increased during this metabolic period. In the second-phase reactor, the metabolic fluctuations of the first phase were smoothed out resulting in a stable biogas production as well as stable bacterial and methanogenic communities. However, the biogas composition followed the metabolic dynamics of the first phase: the hydrogen content increased during the L-period whereas highest CH4/CO2 ratios (up to 2.8) were reached during the G-period. Aceticlastic Methanosaeta as well as hydrogenotrophic Methanoculleus and Methanobacteriaceae were identified as dominant methanogens. Consequently, a directed control of the first-phase stabilizing desired metabolic states can lead to an enhanced productivity regarding chemicals and bioenergy" |
| Keywords: | Anaerobiosis Archaea/growth & development/metabolism Bacteria/growth & development/metabolism *Biofuels *Biota Lactic Acid/metabolism Methane/*metabolism *Silage Volatile Organic Compounds/metabolism Zea mays/*metabolism 454 Pyrosequencing Acidogenesis An; |
| Notes: | "MedlineStrauber, Heike Lucas, Rico Kleinsteuber, Sabine eng Research Support, Non-U.S. Gov't Germany 2015/09/29 Appl Microbiol Biotechnol. 2016 Jan; 100(1):479-91. doi: 10.1007/s00253-015-6996-0. Epub 2015 Sep 28" |
