1
|
Menzel T, Neubauer P, Junne S. Spatial monitoring of hydrolysis in a plug-flow bioreactor: a support for flexible operation? BIORESOUR BIOPROCESS 2024; 11:23. [PMID: 38647945 PMCID: PMC10992403 DOI: 10.1186/s40643-024-00740-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Accepted: 02/04/2024] [Indexed: 04/25/2024] Open
Abstract
Hydrolysis at changing hydraulic retention time, recirculation, bedding straw content in the feed, bioaugmentation and the impact of those changes on gradient formation in the liquid phase in plug-flow reactors (PFRs) was examined. The pH-value, conductivity and oxidation-reduction potential (ORP) were monitored at three spots along the PFRs to study potential correlations to process performance during a total process time of 123 weeks. The on-line monitoring showed good correlations to acidogenesis: namely, the pH and ORP to the acidification, to butyric (and lactic) acid concentration and to the acid yield. The ORP (measured at the inlet) showed the most stable correlation to acidogenesis under dynamic operation, while the conductivity (at the outlet) correlated to the acid concentration in dependence on the feedstock. Multiple measurement spots as used in this study allow to gain more information about acidogenic fermentation than a single spot, simplifying process control and automation attempts with recalcitrant feedstock.
Collapse
Affiliation(s)
- Theresa Menzel
- Chair of Bioprocess Engineering, Institute of Biotechnology, Technische Universität Berlin, Ackerstraße 76, ACK 24, 13355, Berlin, Germany
| | - Peter Neubauer
- Chair of Bioprocess Engineering, Institute of Biotechnology, Technische Universität Berlin, Ackerstraße 76, ACK 24, 13355, Berlin, Germany
| | - Stefan Junne
- Chair of Bioprocess Engineering, Institute of Biotechnology, Technische Universität Berlin, Ackerstraße 76, ACK 24, 13355, Berlin, Germany.
- Department of Chemistry and Bioscience, Aalborg University Esbjerg, Niels Bohrs Vej 8, 6700, Esbjerg, Denmark.
| |
Collapse
|
2
|
Bautista-Cruz A, Aquino-Bolaños T, Hernández-Canseco J, Quiñones-Aguilar EE. Cellulolytic Aerobic Bacteria Isolated from Agricultural and Forest Soils: An Overview. BIOLOGY 2024; 13:102. [PMID: 38392320 PMCID: PMC10886624 DOI: 10.3390/biology13020102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Revised: 01/29/2024] [Accepted: 01/31/2024] [Indexed: 02/24/2024]
Abstract
This review provides insights into cellulolytic bacteria present in global forest and agricultural soils over a period of 11 years. It delves into the study of soil-dwelling cellulolytic bacteria and the enzymes they produce, cellulases, which are crucial in both soil formation and the carbon cycle. Forests and agricultural activities are significant contributors to the production of lignocellulosic biomass. Forest ecosystems, which are key carbon sinks, contain 20-30% cellulose in their leaf litter. Concurrently, the agricultural sector generates approximately 998 million tons of lignocellulosic waste annually. Predominant genera include Bacillus, Pseudomonas, Stenotrophomonas, and Streptomyces in forests and Bacillus, Streptomyces, Pseudomonas, and Arthrobacter in agricultural soils. Selection of cellulolytic bacteria is based on their hydrolysis ability, using artificial cellulose media and dyes like Congo red or iodine for detection. Some studies also measure cellulolytic activity in vitro. Notably, bacterial cellulose hydrolysis capability may not align with their cellulolytic enzyme production. Enzymes such as GH1, GH3, GH5, GH6, GH8, GH9, GH10, GH12, GH26, GH44, GH45, GH48, GH51, GH74, GH124, and GH148 are crucial, particularly GH48 for crystalline cellulose degradation. Conversely, bacteria with GH5 and GH9 often fail to degrade crystalline cellulose. Accurate identification of cellulolytic bacteria necessitates comprehensive genomic analysis, supplemented by additional proteomic and transcriptomic techniques. Cellulases, known for degrading cellulose, are also significant in healthcare, food, textiles, bio-washing, bleaching, paper production, ink removal, and biotechnology, emphasizing the importance of discovering novel cellulolytic strains in soil.
Collapse
Affiliation(s)
- Angélica Bautista-Cruz
- Instituto Politécnico Nacional, CIIDIR-Oaxaca, Hornos 1003, Santa Cruz Xoxocotlán 71230, Oaxaca, Mexico
| | - Teodulfo Aquino-Bolaños
- Instituto Politécnico Nacional, CIIDIR-Oaxaca, Hornos 1003, Santa Cruz Xoxocotlán 71230, Oaxaca, Mexico
| | - Jessie Hernández-Canseco
- Doctoral Programme in Conservation and Use of Natural Resources, Instituto Politécnico Nacional, CIIDIR-Oaxaca, Hornos 1003, Santa Cruz Xoxocotlán 71230, Oaxaca, Mexico
| | - Evangelina Esmeralda Quiñones-Aguilar
- Laboratorio de Fitopatología de Biotecnología Vegetal, Centro de Investigación y Asistencia en Tecnología y Diseño del Estado de Jalisco, A.C. Camino Arenero 1227, El Bajío del Arenal, Zapopan 45019, Jalisco, Mexico
| |
Collapse
|
3
|
Afroze N, Nakhla G, Kim M, Yazdanpanah A. Effects of trace elements on digester performance and microbial community response in anaerobic digestion systems. ENVIRONMENTAL TECHNOLOGY 2023; 44:4157-4172. [PMID: 35611656 DOI: 10.1080/09593330.2022.2082324] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 04/05/2022] [Indexed: 06/15/2023]
Abstract
Trace elements (TE), as micronutrients for microorganisms, have a significant impact on the stability of anaerobic digestion (AD). Studies have been conducted on process stability and performance of the AD of food waste (FW) by supplementing TEs. In this study, mesophilic batch biomethane potential (BMP) tests using FW were conducted to investigate the effect of TEs (Fe, Ni, Co, Se, and Mo) as single and mixed ions. In view of their scarcity, correlations between the microbial community and digester performance such as first-order hydrolysis coefficient (Kh), volatile fatty acids (VFA), methane yield, and methane production rate (MPR) have been developed. Ni2+ at 1 and 1.5 mg/L increased the methane yield by 27% and 23% respectively. Similarly, Co2+ at 0.1 and 0.5 mg/L increased the yield by 21% and 23% respectively, compared to control. Although Se4+ at all concentrations enhanced the methane yield, Fe2+ at only 50 mg/L increased methane yield by 22%. For mixed TEs, the combination of Ni2+ [1 mg/L] +Co2+ was the best and increased methane for all Co2+ concentrations (0.1, 0.4 and 0.5 mg/L) by 16%, 14% and 12% respectively. Firmicutes and Methanosaeta were the most abundant phyla among hydrolytic and methanogenic microbial groups, respectively, constituting 42%-61% and 60-80% of their respective microbial groups. The most significant positive correlations were observed between aceto/acidogenic microorganisms and final VFA concentrations with Pearson correlation factors of 0.91.
Collapse
Affiliation(s)
- Niema Afroze
- Civil and Environmental Engineering, University of Western Ontario, London, ON, Canada
| | - George Nakhla
- Civil and Environmental Engineering, University of Western Ontario, London, ON, Canada
- Chemical and Biochemical Engineering, University of Western Ontario, London, ON, Canada
| | - Mingu Kim
- Chemical and Biochemical Engineering, University of Western Ontario, London, ON, Canada
| | - Andisheh Yazdanpanah
- Civil and Environmental Engineering, University of Western Ontario, London, ON, Canada
- Black & Veatch, Markham, ON, Canada
| |
Collapse
|
4
|
Hassa J, Tubbesing TJ, Maus I, Heyer R, Benndorf D, Effenberger M, Henke C, Osterholz B, Beckstette M, Pühler A, Sczyrba A, Schlüter A. Uncovering Microbiome Adaptations in a Full-Scale Biogas Plant: Insights from MAG-Centric Metagenomics and Metaproteomics. Microorganisms 2023; 11:2412. [PMID: 37894070 PMCID: PMC10608942 DOI: 10.3390/microorganisms11102412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 09/15/2023] [Accepted: 09/18/2023] [Indexed: 10/29/2023] Open
Abstract
The current focus on renewable energy in global policy highlights the importance of methane production from biomass through anaerobic digestion (AD). To improve biomass digestion while ensuring overall process stability, microbiome-based management strategies become more important. In this study, metagenomes and metaproteomes were used for metagenomically assembled genome (MAG)-centric analyses to investigate a full-scale biogas plant consisting of three differentially operated digesters. Microbial communities were analyzed regarding their taxonomic composition, functional potential, as well as functions expressed on the proteome level. Different abundances of genes and enzymes related to the biogas process could be mostly attributed to different process parameters. Individual MAGs exhibiting different abundances in the digesters were studied in detail, and their roles in the hydrolysis, acidogenesis and acetogenesis steps of anaerobic digestion could be assigned. Methanoculleus thermohydrogenotrophicum was an active hydrogenotrophic methanogen in all three digesters, whereas Methanothermobacter wolfeii was more prevalent at higher process temperatures. Further analysis focused on MAGs, which were abundant in all digesters, indicating their potential to ensure biogas process stability. The most prevalent MAG belonged to the class Limnochordia; this MAG was ubiquitous in all three digesters and exhibited activity in numerous pathways related to different steps of AD.
Collapse
Affiliation(s)
- Julia Hassa
- Genome Research of Industrial Microorganisms, Center for Biotechnology (CeBiTec), Bielefeld University, Universitätsstrasse 27, 33615 Bielefeld, Germany; (J.H.)
| | - Tom Jonas Tubbesing
- Computational Metagenomics Group, Center for Biotechnology (CeBiTec), Bielefeld University, Universitätsstraße 27, 33615 Bielefeld, Germany; (T.J.T.)
| | - Irena Maus
- Genome Research of Industrial Microorganisms, Center for Biotechnology (CeBiTec), Bielefeld University, Universitätsstrasse 27, 33615 Bielefeld, Germany; (J.H.)
| | - Robert Heyer
- Multidimensional Omics Data Analyses Group, Leibniz-Institut für Analytische Wissenschaften-ISAS-e.V., Bunsen-Kirchhoff-Straße 11, Dortmund 44139, Germany
- Multidimensional Omics Data Analyses Group, Faculty of Technology, Bielefeld University, Universitätsstraße 25, 33615 Bielefeld, Germany
| | - Dirk Benndorf
- Biosciences and Process Engineering, Anhalt University of Applied Sciences, Bernburger Straße 55, Postfach 1458, 06366 Köthen, Germany
- Bioprocess Engineering, Otto von Guericke University, Universitätsplatz 2, 39106 Magdeburg, Germany
- Bioprocess Engineering, Max Planck Institute for Dynamics of Complex Technical Systems, Sandtorstraße 1, 39106 Magdeburg, Germany
| | - Mathias Effenberger
- Bavarian State Research Center for Agriculture, Institute for Agricultural Engineering and Animal Husbandry, Vöttinger Straße 36, 85354 Freising, Germany
| | - Christian Henke
- Computational Metagenomics Group, Center for Biotechnology (CeBiTec), Bielefeld University, Universitätsstraße 27, 33615 Bielefeld, Germany; (T.J.T.)
| | - Benedikt Osterholz
- Computational Metagenomics Group, Center for Biotechnology (CeBiTec), Bielefeld University, Universitätsstraße 27, 33615 Bielefeld, Germany; (T.J.T.)
| | - Michael Beckstette
- Computational Metagenomics Group, Center for Biotechnology (CeBiTec), Bielefeld University, Universitätsstraße 27, 33615 Bielefeld, Germany; (T.J.T.)
| | - Alfred Pühler
- Genome Research of Industrial Microorganisms, Center for Biotechnology (CeBiTec), Bielefeld University, Universitätsstrasse 27, 33615 Bielefeld, Germany; (J.H.)
| | - Alexander Sczyrba
- Computational Metagenomics Group, Center for Biotechnology (CeBiTec), Bielefeld University, Universitätsstraße 27, 33615 Bielefeld, Germany; (T.J.T.)
| | - Andreas Schlüter
- Genome Research of Industrial Microorganisms, Center for Biotechnology (CeBiTec), Bielefeld University, Universitätsstrasse 27, 33615 Bielefeld, Germany; (J.H.)
| |
Collapse
|
5
|
Menzel T, Neubauer P, Junne S. Plug-flow hydrolysis with lignocellulosic residues: effect of hydraulic retention time and thin-sludge recirculation. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2023; 16:111. [PMID: 37415198 DOI: 10.1186/s13068-023-02363-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Accepted: 06/27/2023] [Indexed: 07/08/2023]
Abstract
BACKGROUND Two parallel plug-flow reactors were successfully applied as a hydrolysis stage for the anaerobic pre-digestion of maize silage and recalcitrant bedding straw (30% and 66% w/w) under variations of the hydraulic retention time (HRT) and thin-sludge recirculation. RESULTS The study proved that the hydrolysis rate profits from shorter HRTs while the hydrolysis yield remained similar and was limited by a low pH-value with values of 264-310 and 180-200 gO2 kgVS-1 for 30% and 66% of bedding straw correspondingly. Longer HRT led to metabolite accumulation, significantly increased gas production, a higher acid production rate and a 10-18% higher acid yield of 78 gSCCA kgVS-1 for 66% of straw. Thin-sludge recirculation increased the acid yield and stabilized the process, especially at a short HRT. Hydrolysis efficiency can thus be improved by shorter HRT, whereas the acidogenic process performance is increased by longer HRT and thin-sludge recirculation. Two main fermentation patterns of the acidogenic community were found: above a pH-value of 3.8, butyric and acetic acid were the main products, while below a pH-value of 3.5, lactic, acetic and succinic acid were mainly accumulating. During plug-flow digestion with recirculation, at low pH-values, butyric acid remained high compared to all other acids. Both fermentation patterns had virtually equal yields of hydrolysis and acidogenesis and showed good reproducibility among the parallel reactor operation. CONCLUSIONS The suitable combination of HRT and thin-sludge recirculation proved to be useful in a plug-flow hydrolysis as primary stage in biorefinery systems with the benefits of a wider feedstock spectrum including feedstock with cellulolytic components at an increased process robustness against changes in the feedstock composition.
Collapse
Affiliation(s)
- Theresa Menzel
- Chair of Bioprocess Engineering, Institute of Biotechnology, Technische Universität Berlin, Ackerstraße 76, ACK 24, 13355, Berlin, Germany
| | - Peter Neubauer
- Chair of Bioprocess Engineering, Institute of Biotechnology, Technische Universität Berlin, Ackerstraße 76, ACK 24, 13355, Berlin, Germany
| | - Stefan Junne
- Chair of Bioprocess Engineering, Institute of Biotechnology, Technische Universität Berlin, Ackerstraße 76, ACK 24, 13355, Berlin, Germany.
- Department of Chemistry and Bioscience, Aalborg University Esbjerg, Niels Bohrs Vej 8, 6700, Esbjerg, Denmark.
| |
Collapse
|
6
|
Li W, Zhu L, Wu B, Liu Y, Li J, Xu L, Huangfu X, Shi D, Gu L, Chen C. Improving mesophilic anaerobic digestion of food waste by side-stream thermophilic reactor: Activation of methanogenic, key enzymes and metabolism. WATER RESEARCH 2023; 241:120167. [PMID: 37290195 DOI: 10.1016/j.watres.2023.120167] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2023] [Revised: 05/21/2023] [Accepted: 06/01/2023] [Indexed: 06/10/2023]
Abstract
Anaerobic digestion (AD) is a favorable way to convert organic pollutants, such as food waste (FW), into clean energy through microbial action. This work adopted a side-stream thermophilic anaerobic digestion (STA) strategy to improve a digestive system's efficiency and stability. Results showed that the STA strategy brought higher methane production as well as higher system stability. It quickly adapted to thermal stimulation and increased the specific methane production from 359 mL CH4/g·VS to 439 mL CH4/g·VS, which was also higher than 317 mL CH4/g·VS from single-stage thermophilic anaerobic digestion. Further exploration of the mechanism of STA using metagenomic and metaproteomic analysis revealed enhanced activity of key enzymes. The main metabolic pathway was up-regulated, while the dominant bacteria were concentrated, and the multifunctional Methanosarcina was enriched. These results indicate that STA optimized organic metabolism patterns, comprehensively promoted methane production pathways, and formed various energy conservation mechanisms. Further, the system's limited heating avoided adverse effects from thermal stimulation, and activated enzyme activity and heat shock proteins through circulating slurries, which improved the metabolic process, showing great application potential.
Collapse
Affiliation(s)
- Wen Li
- Key laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Environment and Ecology, Chongqing University, 174 Shapingba Road, Chongqing, 400045, PR China
| | - Lirong Zhu
- Key laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Environment and Ecology, Chongqing University, 174 Shapingba Road, Chongqing, 400045, PR China
| | - Baocun Wu
- Key laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Environment and Ecology, Chongqing University, 174 Shapingba Road, Chongqing, 400045, PR China
| | - Yongli Liu
- Key laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Environment and Ecology, Chongqing University, 174 Shapingba Road, Chongqing, 400045, PR China
| | - Jinze Li
- Key laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Environment and Ecology, Chongqing University, 174 Shapingba Road, Chongqing, 400045, PR China
| | - Linji Xu
- Key laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Environment and Ecology, Chongqing University, 174 Shapingba Road, Chongqing, 400045, PR China
| | - Xiaoliu Huangfu
- Key laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Environment and Ecology, Chongqing University, 174 Shapingba Road, Chongqing, 400045, PR China
| | - Dezhi Shi
- Key laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Environment and Ecology, Chongqing University, 174 Shapingba Road, Chongqing, 400045, PR China
| | - Li Gu
- Key laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Environment and Ecology, Chongqing University, 174 Shapingba Road, Chongqing, 400045, PR China.
| | - Cong Chen
- Key laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Environment and Ecology, Chongqing University, 174 Shapingba Road, Chongqing, 400045, PR China
| |
Collapse
|
7
|
Wang M, Chen H, Chang S. Impact of combined biological hydrolysis and anaerobic digestion temperatures on the characteristics of bacterial community and digestate quality in the treatment of wastewater sludge. BIORESOURCE TECHNOLOGY 2022; 362:127796. [PMID: 35988857 DOI: 10.1016/j.biortech.2022.127796] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Revised: 08/12/2022] [Accepted: 08/14/2022] [Indexed: 06/15/2023]
Abstract
This work investigated the impact of temperature on the digestate water quality and bacterial community in the treatment of wastewater sludge using biological hydrolysis (BH)-anaerobic digestion (AD). The results showed that the BH 55 °C followed by AD 35 °C or 42 °C was the optimal temperature combination in terms of methane yield and digestate water quality. High-throughput sequencing revealed the key differences in bacterial communities for different BH-AD temperature combinations. Microbial source tracking showed only minor microbial migration from raw sludge and BH pre-treated sludge to the AD stage. Strong correlations between the residual sCOD, BH-AD temperature conditions, and dominant bacteria were identified. Clostridiales, Bacteroidales, Cloacimonadales, Thermotogales, and Anaerolineales were closely related to the digestate water quality and methane yield. Overall, the results showed that AD temperature exerted a dominant impact on methane yield, digestate water quality, and bacterial compositions in the BH-AD of wastewater sludge.
Collapse
Affiliation(s)
- Meiying Wang
- School of Engineering, University of Guelph, Ontario N1G 2W1, Canada
| | - Huibin Chen
- School of Engineering, University of Guelph, Ontario N1G 2W1, Canada; College of Life Sciences, Fujian Normal University, Fuzhou 350117, China
| | - Sheng Chang
- School of Engineering, University of Guelph, Ontario N1G 2W1, Canada.
| |
Collapse
|
8
|
Rettenmaier R, Kowollik ML, Klingl A, Liebl W, Zverlov V. Ruminiclostridium herbifermentans sp. nov., a mesophilic and moderately thermophilic cellulolytic and xylanolytic bacterium isolated from a lab-scale biogas fermenter fed with maize silage. Int J Syst Evol Microbiol 2021; 71. [PMID: 33555241 DOI: 10.1099/ijsem.0.004692] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
An anaerobic bacterial strain, designated MA18T, was isolated from a laboratory-scale biogas fermenter fed with maize silage. Cells stained Gram-negative and performed Gram-negative in the KOH test. The peptidoglycan type was found to be A1y-meso-Dpm direct. The major cellular fatty acids were C14 : 0 iso, C15 : 0 iso, anteiso and iso DMA as well as a C16 unidentified fatty acid. Oxidase and catalase activities were absent. Cells were slightly curved rods, motile, formed spores and measured approximately 0.35 µm in diameter and 3.0-5.0 µm in length. When cultivated on GS2 agar with cellobiose, round, arched, shiny and slightly yellow-pigmented colonies were formed. The isolate was mesophilic to moderately thermophilic with a growth optimum between 40 and 48 °C. Furthermore, neutral pH values were preferred and up to 1.2 % (w/v) NaCl supplemented to the GS2 medium was tolerated. Producing mainly acetate and ethanol, MA18T fermented arabinose, cellobiose, crystalline and amorphous cellulose, ribose, and xylan. The genome of MA18T consists of 4 817 678 bp with a G+C content of 33.16 mol%. In the annotated protein sequences, cellulosomal components were detected. Phylogenetically, MA18T is most closely related to Ruminiclostridium sufflavum DSM 19573T (76.88 % average nucleotide identity of the whole genome sequence; 97.23 % 16S rRNA gene sequence similarity) and can be clustered into one clade with other species of the genus Ruminiclostridium, family Oscillospiraceae, class Clostridia. Based on morphological, physiological and genetic characteristics, this strain represents a novel species in the genus Ruminiclostridium. Therefore, the name Ruminiclostridium herbifermentans sp. nov. is proposed. The type strain is MA18T (=DSM 109966T=JCM 39124T).
Collapse
Affiliation(s)
- Regina Rettenmaier
- Technical University of Munich, Chair of Microbiology, Emil-Ramann-Str. 4, 85354 Freising, Germany
| | - Marie-Louise Kowollik
- Technical University of Munich, Chair of Microbiology, Emil-Ramann-Str. 4, 85354 Freising, Germany
| | - Andreas Klingl
- LMU Munich, Plant Development & Electron Microscopy, Biocenter LMU Munich, Großhadernerstr. 2-4, 82152 Planegg-Martinsried, Germany
| | - Wolfgang Liebl
- Technical University of Munich, Chair of Microbiology, Emil-Ramann-Str. 4, 85354 Freising, Germany
| | - Vladimir Zverlov
- Institute of Molecular Genetics of National Research Centre «Kurchatov Institute», Kurchatov Sq. 2, 123182 Moscow, Russia.,Technical University of Munich, Chair of Microbiology, Emil-Ramann-Str. 4, 85354 Freising, Germany
| |
Collapse
|
9
|
Rettenmaier R, Lo YK, Schmidt L, Munk B, Lagkouvardos I, Neuhaus K, Schwarz W, Liebl W, Zverlov V. A Novel Primer Mixture for GH48 Genes: Quantification and Identification of Truly Cellulolytic Bacteria in Biogas Fermenters. Microorganisms 2020; 8:E1297. [PMID: 32854333 PMCID: PMC7565076 DOI: 10.3390/microorganisms8091297] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 08/21/2020] [Accepted: 08/23/2020] [Indexed: 12/22/2022] Open
Abstract
Genomic studies revealed the glycoside hydrolases of family 48 (GH48) as a powerful marker for the identification of truly cellulolytic bacteria. Here we report an improved method for detecting cellulolytic bacteria in lab-scale biogas fermenters by using GH48 genes as a molecular marker in DNA and RNA samples. We developed a mixture of primers for the specific amplification of a GH48 gene region in a broad range of bacteria. Additionally, we built a manually curated reference database containing GH48 gene sequences directly linked to the corresponding taxonomic information. Phylogenetic correlation analysis of GH48 to 16S rRNA gene sequences revealed that GH48 gene sequences with 94% identity belong with high confidence to the same genus. Applying this analysis, GH48 amplicon reads revealed that at mesophilic fermenter conditions, 50-99% of the OTUs appear to belong to novel taxa. In contrast, at thermophilic conditions, GH48 gene sequences from the genus Hungateiclostridium dominated with 60-91% relative abundance. The novel primer combinations enabled detection and relative quantification of a wide spectrum of GH48 genes in cellulolytic microbial communities. Deep phylogenetic correlation analysis and a simplified taxonomic identification with the novel database facilitate identification of cellulolytic organisms, including the detection of novel taxa in biogas fermenters.
Collapse
Affiliation(s)
- Regina Rettenmaier
- Chair of Microbiology, Technical University of Munich, Emil-Ramann-Str. 4, 85354 Freising, Germany; (R.R.); (Y.K.L.); (L.S.); (W.L.)
| | - Yat Kei Lo
- Chair of Microbiology, Technical University of Munich, Emil-Ramann-Str. 4, 85354 Freising, Germany; (R.R.); (Y.K.L.); (L.S.); (W.L.)
| | - Larissa Schmidt
- Chair of Microbiology, Technical University of Munich, Emil-Ramann-Str. 4, 85354 Freising, Germany; (R.R.); (Y.K.L.); (L.S.); (W.L.)
| | - Bernhard Munk
- Bavarian State Research Center for Agriculture, Central Department for Quality Assurance and Analytics, Lange Point 6, 85354 Freising, Germany;
| | - Ilias Lagkouvardos
- ZIEL—Core Facility Microbiome, Technical University of Munich, Weihenstephaner Berg 3, 85354 Freising, Germany; (I.L.); (K.N.)
| | - Klaus Neuhaus
- ZIEL—Core Facility Microbiome, Technical University of Munich, Weihenstephaner Berg 3, 85354 Freising, Germany; (I.L.); (K.N.)
| | - Wolfgang Schwarz
- Aspratis GmbH. Munich, Germany, Hübnerstr. 11, 80637 Munich, Germany;
| | - Wolfgang Liebl
- Chair of Microbiology, Technical University of Munich, Emil-Ramann-Str. 4, 85354 Freising, Germany; (R.R.); (Y.K.L.); (L.S.); (W.L.)
| | - Vladimir Zverlov
- Chair of Microbiology, Technical University of Munich, Emil-Ramann-Str. 4, 85354 Freising, Germany; (R.R.); (Y.K.L.); (L.S.); (W.L.)
- Institute of Molecular Genetics of National Research Centre (Kurchatov Institute), Kurchatov Sq. 2, 123182 Moscow, Russia
| |
Collapse
|
10
|
Sekoai PT, Engelbrecht N, du Preez SP, Bessarabov D. Thermophilic Biogas Upgrading via ex Situ Addition of H 2 and CO 2 Using Codigested Feedstocks of Cow Manure and the Organic Fraction of Solid Municipal Waste. ACS OMEGA 2020; 5:17367-17376. [PMID: 32715221 PMCID: PMC7377068 DOI: 10.1021/acsomega.0c01725] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Accepted: 06/18/2020] [Indexed: 06/11/2023]
Abstract
Bioconversion of renewable H2 and waste CO2 using methanogenic archaea is a promising technology for obtaining high-purity CH4, which can serve as an alternative for natural gas. This process is known as ex situ biogas upgrading. This work highlights the pathway toward the bioconversion of renewable H2 and CO2 into high-purity biomethane by exploiting highly accessible agro-municipal residues: cow manure (CM) and the organic fraction of solid municipal waste (OFSMW), which used to be called "waste materials". More specifically, an ex situ thermophilic (55 °C) biogas upgrading process was conducted by CM and OFSMW codigestion at different mass proportions: 100:0, 80:20, 70:30, 60:40, and 50:50. Maximum CH4 concentrations of 92-97 vol % and biogas volumetric production rates of 4954-6605 NmL/L.d were obtained from a batch reactor of 3 L working volume. Feedstock characterization, pH monitoring, and the carbon-to-nitrogen ratio were critical parameters to evaluate during biogas upgrading experiments. In this work, the usefulness of agro-municipal substrates is highlighted by producing high-purity biomethane-an energetic chemical to facilitate renewable energy conversion, which supports various end-use applications. This process therefore provides a solution to renewable energy storage challenges and future sustainable and green energy supply.
Collapse
|
11
|
Hungateiclostridium mesophilum sp. nov., a mesophilic, cellulolytic and spore-forming bacterium isolated from a biogas fermenter fed with maize silage. Int J Syst Evol Microbiol 2019; 69:3567-3573. [DOI: 10.1099/ijsem.0.003663] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
|
12
|
Zealand AM, Mei R, Roskilly AP, Liu W, Graham DW. Molecular microbial ecology of stable versus failing rice straw anaerobic digesters. Microb Biotechnol 2019; 12:879-891. [PMID: 31233284 PMCID: PMC6681398 DOI: 10.1111/1751-7915.13438] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Revised: 05/13/2019] [Accepted: 05/14/2019] [Indexed: 12/01/2022] Open
Abstract
Waste rice straw (RS) is generated in massive quantities around the world and is often burned, creating greenhouse gas and air quality problems. Anaerobic digestion (AD) may be a better option for RS management, but RS is presumed to be comparatively refractory under anaerobic conditions without pre-treatment or co-substrates. However, this presumption assumes frequent reactor feeding regimes but less frequent feeding may be better for RS due to slow hydrolysis rates. Here, we assess how feeding frequency (FF) and organic loading rate (OLR) impacts microbial communities and biogas production in RS AD reactors. Using 16S rDNA amplicon sequencing and bioinformatics, microbial communities from five bench-scale bioreactors were characterized. At low OLR (1.0 g VS l-1 day-1 ), infrequently fed units (once every 21 days) had higher specific biogas yields than more frequent feeding (five in 7 days), although microbial community diversities were statistically similar (P > 0.05; ANOVA with Tukey comparison). In contrast, an increase in OLR to 2.0 g VS l-1 day-1 significantly changed Archaeal and fermenting Eubacterial sub-communities and the least frequency fed reactors failed. 'Stable' reactors were dominated by Methanobacterium, Methanosarcina and diverse Bacteroidetes, whereas 'failed' reactors saw shifts towards Clostridia and Christensenellaceae among fermenters and reduced methanogen abundances. Overall, OLR impacted RS AD microbial communities more than FF. However, combining infrequent feeding and lower OLRs may be better for RS AD because of higher specific yields.
Collapse
Affiliation(s)
- Andrew M. Zealand
- School of EngineeringNewcastle UniversityNewcastle upon TyneNE1 7RUUK
| | - Ran Mei
- Department of Civil and Environmental EngineeringUniversity of Illinois at Urbana‐Champaign205 North Mathews AveUrbanaIL61801USA
| | - Anthony P. Roskilly
- Sir Joseph Swan Centre for Energy ResearchNewcastle UniversityNewcastle upon TyneNE1 7RUUK
| | - WenTso Liu
- Department of Civil and Environmental EngineeringUniversity of Illinois at Urbana‐Champaign205 North Mathews AveUrbanaIL61801USA
| | - David W. Graham
- School of EngineeringNewcastle UniversityNewcastle upon TyneNE1 7RUUK
| |
Collapse
|
13
|
Rettenmaier R, Duerr C, Neuhaus K, Liebl W, Zverlov VV. Comparison of sampling techniques and different media for the enrichment and isolation of cellulolytic organisms from biogas fermenters. Syst Appl Microbiol 2019; 42:481-487. [DOI: 10.1016/j.syapm.2019.05.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Revised: 05/15/2019] [Accepted: 05/17/2019] [Indexed: 12/22/2022]
|
14
|
Recent Updates on the Use of Agro-Food Waste for Biogas Production. APPLIED SCIENCES-BASEL 2019. [DOI: 10.3390/app9061217] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The production of biogas from anaerobic digestion (AD) of residual agro-food biomasses represents an opportunity for alternative production of energy from renewable sources, according to the European Union legislation on renewable energy. This review provides an overview of the various aspects involved in this process with a focus on the best process conditions to be used for AD-based biogas production from residual agro-food biomasses. After a schematic description of the AD phases, the biogas plants with advanced technologies were described, pointing out the strengths and the weaknesses of the different digester technologies and indicating the main parameters and operating conditions to be monitored. Subsequently, a brief analysis of the factors affecting methane yield from manure AD was conducted and the AD of fruit and vegetables waste was examined. Particular attention was given to studies on co-digestion and pre-treatments as strategies to improve biogas yield. Finally, the selection of specific microorganisms and the genetic manipulation of anaerobic bacteria to speed up the AD process was illustrated. The open challenges concern the achievement of the highest renewable energy yields reusing agro-food waste with the lowest environmental impact and an increment of competitiveness of the agricultural sector in the perspective of a circular economy.
Collapse
|
15
|
Froese A, Schellenberg J, Sparling R. Enhanced depolymerization and utilization of raw lignocellulosic material by co-cultures of Ruminiclostridium thermocellum with hemicellulose-utilizing partners. Can J Microbiol 2019; 65:296-307. [PMID: 30608879 DOI: 10.1139/cjm-2018-0535] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Ruminiclostridium thermocellum is one of the most promising candidates for consolidated bioprocessing (CBP) of low-cost lignocellulosic materials to biofuels but it still shows poor performance in its ability to deconstruct untreated lignocellulosic substrates. One promising approach to increase R. thermocellum's rate of hydrolysis is to co-culture this cellulose-specialist with partners that possess synergistic hydrolysis enzymes and metabolic capabilities. We have created co-cultures of R. thermocellum with two hemicellulose utilizers, Ruminiclostridium stercorarium and Thermoanaerobacter thermohydrosulfuricus, both of which secrete xylanolytic enzymes and utilize the pentose oligo- and monosaccharides that inhibit R. thermocellum's hydrolysis and metabolism. When grown on milled wheat straw, the co-cultures were able to solubilize up to 58% more of the total polysaccharides than the R. thermocellum mono-culture control. Repeated passaging of the co-cultures on wheat straw yielded stable populations with reduced R. thermocellum cell numbers, indicating competition for cellodextrins released from cellulose hydrolysis, although these stabilized co-cultures were still able to outperform the mono-culture controls. Repeated passaging on Avicel cellulose also yielded stable populations. Overall, the observed synergism suggests that co-culturing R. thermocellum with other members is a viable option for increasing the rate and extent of untreated lignocellulose deconstruction by R. thermocellum for CBP purposes.
Collapse
Affiliation(s)
- Alan Froese
- Department of Microbiology, University of Manitoba, Winnipeg, MB R3T 2N2, Canada.,Department of Microbiology, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
| | - John Schellenberg
- Department of Microbiology, University of Manitoba, Winnipeg, MB R3T 2N2, Canada.,Department of Microbiology, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
| | - Richard Sparling
- Department of Microbiology, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
| |
Collapse
|
16
|
Broeker J, Mechelke M, Baudrexl M, Mennerich D, Hornburg D, Mann M, Schwarz WH, Liebl W, Zverlov VV. The hemicellulose-degrading enzyme system of the thermophilic bacterium Clostridium stercorarium: comparative characterisation and addition of new hemicellulolytic glycoside hydrolases. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:229. [PMID: 30159029 PMCID: PMC6106730 DOI: 10.1186/s13068-018-1228-3] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Accepted: 08/14/2018] [Indexed: 05/15/2023]
Abstract
BACKGROUND The bioconversion of lignocellulosic biomass in various industrial processes, such as the production of biofuels, requires the degradation of hemicellulose. Clostridium stercorarium is a thermophilic bacterium, well known for its outstanding hemicellulose-degrading capability. Its genome comprises about 50 genes for partially still uncharacterised thermostable hemicellulolytic enzymes. These are promising candidates for industrial applications. RESULTS To reveal the hemicellulose-degrading potential of 50 glycoside hydrolases, they were recombinantly produced and characterised. 46 of them were identified in the secretome of C. stercorarium cultivated on cellobiose. Xylanases Xyn11A, Xyn10B, Xyn10C, and cellulase Cel9Z were among the most abundant proteins. The secretome of C. stercorarium was active on xylan, β-glucan, xyloglucan, galactan, and glucomannan. In addition, the recombinant enzymes hydrolysed arabinan, mannan, and galactomannan. 20 enzymes are newly described, degrading xylan, galactan, arabinan, mannan, and aryl-glycosides of β-d-xylose, β-d-glucose, β-d-galactose, α-l-arabinofuranose, α-l-rhamnose, β-d-glucuronic acid, and N-acetyl-β-d-glucosamine. The activities of three enzymes with non-classified glycoside hydrolase (GH) family modules were determined. Xylanase Xyn105F and β-d-xylosidase Bxl31D showed activities not described so far for their GH families. 11 of the 13 polysaccharide-degrading enzymes were most active at pH 5.0 to pH 6.5 and at temperatures of 57-76 °C. Investigation of the substrate and product specificity of arabinoxylan-degrading enzymes revealed that only the GH10 xylanases were able to degrade arabinoxylooligosaccharides. While Xyn10C was inhibited by α-(1,2)-arabinosylations, Xyn10D showed a degradation pattern different to Xyn10B and Xyn10C. Xyn11A released longer degradation products than Xyn10B. Both tested arabinose-releasing enzymes, Arf51B and Axh43A, were able to hydrolyse single- as well as double-arabinosylated xylooligosaccharides. CONCLUSIONS The obtained results lead to a better understanding of the hemicellulose-degrading capacity of C. stercorarium and its involved enzyme systems. Despite similar average activities measured by depolymerisation tests, a closer look revealed distinctive differences in the activities and specificities within an enzyme class. This may lead to synergistic effects and influence the enzyme choice for biotechnological applications. The newly characterised glycoside hydrolases can now serve as components of an enzyme platform for industrial applications in order to reconstitute synthetic enzyme systems for complete and optimised degradation of defined polysaccharides and hemicellulose.
Collapse
Affiliation(s)
- Jannis Broeker
- Department of Microbiology, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Emil-Ramann-Str. 4, 85354 Freising, Germany
| | - Matthias Mechelke
- Department of Microbiology, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Emil-Ramann-Str. 4, 85354 Freising, Germany
| | - Melanie Baudrexl
- Department of Microbiology, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Emil-Ramann-Str. 4, 85354 Freising, Germany
| | - Denise Mennerich
- Department of Microbiology, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Emil-Ramann-Str. 4, 85354 Freising, Germany
| | - Daniel Hornburg
- Present Address: School of Medicine, Stanford University, Stanford, CA 94305 USA
- Max Planck Institute of Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany
| | - Matthias Mann
- Max Planck Institute of Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany
| | - Wolfgang H. Schwarz
- Department of Microbiology, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Emil-Ramann-Str. 4, 85354 Freising, Germany
| | - Wolfgang Liebl
- Department of Microbiology, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Emil-Ramann-Str. 4, 85354 Freising, Germany
| | - Vladimir V. Zverlov
- Department of Microbiology, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Emil-Ramann-Str. 4, 85354 Freising, Germany
- Institute of Molecular Genetics, Russian Academy of Science, Kurchatov Sq. 2, Moscow, 123182 Russia
| |
Collapse
|
17
|
Ravi PP, Lindner J, Oechsner H, Lemmer A. Effects of target pH-value on organic acids and methane production in two-stage anaerobic digestion of vegetable waste. BIORESOURCE TECHNOLOGY 2018; 247:96-102. [PMID: 28946100 DOI: 10.1016/j.biortech.2017.09.068] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Revised: 09/07/2017] [Accepted: 09/08/2017] [Indexed: 06/07/2023]
Abstract
Vegetable waste is one of the major organic residues available for sustainable bioenergy production. The aim of this work is to study the influence of pH-value on process stability, hydrolysis, degradation degree and methane production in two-stage anaerobic system. A mixture of vegetable wastes with carrot mousse, carrots, celery, cabbage and potatoes was treated in two-stage system at target pH-values 5.5 and 6 in acidification reactor (AR). At pH 6, high concentrations of organic acids were recorded whereas high amount of hydrolysate was produced at pH 5.5. The chemical oxygen demand (COD) concentration in the hydrolysate produced in AR was 21.85% higher at pH 6 compared to pH 5.5, whereas the overall specific methane yield was slightly higher at pH 5.5 (354.35±31.95 and 326.79±41.42Lkg-1 oDMadded, respectively). It could be shown, that the described two-stage system is well suited for manure-free digestion of vegetable waste.
Collapse
Affiliation(s)
- Padma Priya Ravi
- University of Hohenheim, State Institute of Agricultural Engineering and Bioenergy, Garbenstraße 9, 70 599 Stuttgart, Germany.
| | - Jonas Lindner
- University of Hohenheim, State Institute of Agricultural Engineering and Bioenergy, Garbenstraße 9, 70 599 Stuttgart, Germany
| | - Hans Oechsner
- University of Hohenheim, State Institute of Agricultural Engineering and Bioenergy, Garbenstraße 9, 70 599 Stuttgart, Germany
| | - Andreas Lemmer
- University of Hohenheim, State Institute of Agricultural Engineering and Bioenergy, Garbenstraße 9, 70 599 Stuttgart, Germany
| |
Collapse
|
18
|
Maus I, Koeck DE, Cibis KG, Hahnke S, Kim YS, Langer T, Kreubel J, Erhard M, Bremges A, Off S, Stolze Y, Jaenicke S, Goesmann A, Sczyrba A, Scherer P, König H, Schwarz WH, Zverlov VV, Liebl W, Pühler A, Schlüter A, Klocke M. Unraveling the microbiome of a thermophilic biogas plant by metagenome and metatranscriptome analysis complemented by characterization of bacterial and archaeal isolates. BIOTECHNOLOGY FOR BIOFUELS 2016; 9:171. [PMID: 27525040 PMCID: PMC4982221 DOI: 10.1186/s13068-016-0581-3] [Citation(s) in RCA: 89] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Accepted: 07/27/2016] [Indexed: 05/24/2023]
Abstract
BACKGROUND One of the most promising technologies to sustainably produce energy and to mitigate greenhouse gas emissions from combustion of fossil energy carriers is the anaerobic digestion and biomethanation of organic raw material and waste towards biogas by highly diverse microbial consortia. In this context, the microbial systems ecology of thermophilic industrial-scale biogas plants is poorly understood. RESULTS The microbial community structure of an exemplary thermophilic biogas plant was analyzed by a comprehensive approach comprising the analysis of the microbial metagenome and metatranscriptome complemented by the cultivation of hydrolytic and acido-/acetogenic Bacteria as well as methanogenic Archaea. Analysis of metagenome-derived 16S rRNA gene sequences revealed that the bacterial genera Defluviitoga (5.5 %), Halocella (3.5 %), Clostridium sensu stricto (1.9 %), Clostridium cluster III (1.5 %), and Tepidimicrobium (0.7 %) were most abundant. Among the Archaea, Methanoculleus (2.8 %) and Methanothermobacter (0.8 %) were predominant. As revealed by a metatranscriptomic 16S rRNA analysis, Defluviitoga (9.2 %), Clostridium cluster III (4.8 %), and Tepidanaerobacter (1.1 %) as well as Methanoculleus (5.7 %) mainly contributed to these sequence tags indicating their metabolic activity, whereas Hallocella (1.8 %), Tepidimicrobium (0.5 %), and Methanothermobacter (<0.1 %) were transcriptionally less active. By applying 11 different cultivation strategies, 52 taxonomically different microbial isolates representing the classes Clostridia, Bacilli, Thermotogae, Methanomicrobia and Methanobacteria were obtained. Genome analyses of isolates support the finding that, besides Clostridium thermocellum and Clostridium stercorarium, Defluviitoga tunisiensis participated in the hydrolysis of hemicellulose producing ethanol, acetate, and H2/CO2. The latter three metabolites are substrates for hydrogentrophic and acetoclastic archaeal methanogenesis. CONCLUSIONS Obtained results showed that high abundance of microorganisms as deduced from metagenome analysis does not necessarily indicate high transcriptional or metabolic activity, and vice versa. Additionally, it appeared that the microbiome of the investigated thermophilic biogas plant comprised a huge number of up to now unknown and insufficiently characterized species.
Collapse
Affiliation(s)
- Irena Maus
- Center for Biotechnology (CeBiTec), Institute for Genome Research and Systems Biology, Bielefeld University, Universitätsstr. 27, 33615 Bielefeld, Germany
| | - Daniela E. Koeck
- Department of Microbiology, Technische Universität München, Emil-Ramann-Str. 4, 85354 Freising-Weihenstephan, Germany
| | - Katharina G. Cibis
- Institute of Microbiology and Wine Research, Johannes Gutenberg-University, Becherweg 15, 55128 Mainz, Germany
| | - Sarah Hahnke
- Dept. Bioengineering, Leibniz-Institut für Agrartechnik Potsdam-Bornim e.V. (ATB), Max-Eyth-Allee 100, 14469 Potsdam, Germany
| | - Yong S. Kim
- Faculty Life Sciences/Research Center ‚‘Biomass Utilization Hamburg’, University of Applied Sciences Hamburg (HAW), Ulmenliet 20, 21033 Hamburg-Bergedorf, Germany
| | - Thomas Langer
- Dept. Bioengineering, Leibniz-Institut für Agrartechnik Potsdam-Bornim e.V. (ATB), Max-Eyth-Allee 100, 14469 Potsdam, Germany
| | - Jana Kreubel
- Institute of Microbiology and Wine Research, Johannes Gutenberg-University, Becherweg 15, 55128 Mainz, Germany
| | - Marcel Erhard
- RIPAC-LABOR GmbH, Am Mühlenberg 11, 14476 Potsdam-Golm, Germany
| | - Andreas Bremges
- Center for Biotechnology (CeBiTec), Institute for Genome Research and Systems Biology, Bielefeld University, Universitätsstr. 27, 33615 Bielefeld, Germany
- Faculty of Technology, Bielefeld University, Universitätsstr. 25, 33615 Bielefeld, Germany
| | - Sandra Off
- Faculty Life Sciences/Research Center ‚‘Biomass Utilization Hamburg’, University of Applied Sciences Hamburg (HAW), Ulmenliet 20, 21033 Hamburg-Bergedorf, Germany
| | - Yvonne Stolze
- Center for Biotechnology (CeBiTec), Institute for Genome Research and Systems Biology, Bielefeld University, Universitätsstr. 27, 33615 Bielefeld, Germany
| | - Sebastian Jaenicke
- Department of Bioinformatics and Systems Biology, Justus-Liebig University Gießen, Heinrich-Buff-Ring 58, 35392 Giessen, Germany
| | - Alexander Goesmann
- Department of Bioinformatics and Systems Biology, Justus-Liebig University Gießen, Heinrich-Buff-Ring 58, 35392 Giessen, Germany
| | - Alexander Sczyrba
- Center for Biotechnology (CeBiTec), Institute for Genome Research and Systems Biology, Bielefeld University, Universitätsstr. 27, 33615 Bielefeld, Germany
- Faculty of Technology, Bielefeld University, Universitätsstr. 25, 33615 Bielefeld, Germany
| | - Paul Scherer
- Faculty Life Sciences/Research Center ‚‘Biomass Utilization Hamburg’, University of Applied Sciences Hamburg (HAW), Ulmenliet 20, 21033 Hamburg-Bergedorf, Germany
| | - Helmut König
- Institute of Microbiology and Wine Research, Johannes Gutenberg-University, Becherweg 15, 55128 Mainz, Germany
| | - Wolfgang H. Schwarz
- Department of Microbiology, Technische Universität München, Emil-Ramann-Str. 4, 85354 Freising-Weihenstephan, Germany
| | - Vladimir V. Zverlov
- Department of Microbiology, Technische Universität München, Emil-Ramann-Str. 4, 85354 Freising-Weihenstephan, Germany
| | - Wolfgang Liebl
- Department of Microbiology, Technische Universität München, Emil-Ramann-Str. 4, 85354 Freising-Weihenstephan, Germany
| | - Alfred Pühler
- Center for Biotechnology (CeBiTec), Institute for Genome Research and Systems Biology, Bielefeld University, Universitätsstr. 27, 33615 Bielefeld, Germany
| | - Andreas Schlüter
- Center for Biotechnology (CeBiTec), Institute for Genome Research and Systems Biology, Bielefeld University, Universitätsstr. 27, 33615 Bielefeld, Germany
| | - Michael Klocke
- Dept. Bioengineering, Leibniz-Institut für Agrartechnik Potsdam-Bornim e.V. (ATB), Max-Eyth-Allee 100, 14469 Potsdam, Germany
| |
Collapse
|
19
|
Lindner J, Zielonka S, Oechsner H, Lemmer A. Is the continuous two-stage anaerobic digestion process well suited for all substrates? BIORESOURCE TECHNOLOGY 2016; 200:470-476. [PMID: 26519699 DOI: 10.1016/j.biortech.2015.10.052] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Revised: 10/02/2015] [Accepted: 10/06/2015] [Indexed: 06/05/2023]
Abstract
Two-stage anaerobic digestion systems are often considered to be advantageous compared to one-stage processes. Although process conditions and fermenter setups are well examined, overall substrate degradation in these systems is controversially discussed. Therefore, the aim of this study was to investigate how substrates with different fibre and sugar contents (hay/straw, maize silage, sugar beet) influence the degradation rate and methane production. Intermediates and gas compositions, as well as methane yields and VS-degradation degrees were recorded. The sugar beet substrate lead to a higher pH-value drop 5.67 in the acidification reactor, which resulted in a six time higher hydrogen production in comparison to the hay/straw substrate (pH-value drop 5.34). As the achieved yields in the two-stage system showed a difference of 70.6% for the hay/straw substrate, and only 7.8% for the sugar beet substrate. Therefore two-stage systems seem to be only recommendable for digesting sugar rich substrates.
Collapse
Affiliation(s)
- Jonas Lindner
- University of Hohenheim, State Institute of Agricultural Engineering and Bioenergy, Garbenstraße 9, 70 599 Stuttgart, Germany.
| | - Simon Zielonka
- University of Hohenheim, State Institute of Agricultural Engineering and Bioenergy, Garbenstraße 9, 70 599 Stuttgart, Germany
| | - Hans Oechsner
- University of Hohenheim, State Institute of Agricultural Engineering and Bioenergy, Garbenstraße 9, 70 599 Stuttgart, Germany
| | - Andreas Lemmer
- University of Hohenheim, State Institute of Agricultural Engineering and Bioenergy, Garbenstraße 9, 70 599 Stuttgart, Germany
| |
Collapse
|
20
|
Ziganshina EE, Belostotskiy DE, Ilinskaya ON, Boulygina EA, Grigoryeva TV, Ziganshin AM. Effect of the Organic Loading Rate Increase and the Presence of Zeolite on Microbial Community Composition and Process Stability During Anaerobic Digestion of Chicken Wastes. MICROBIAL ECOLOGY 2015; 70:948-60. [PMID: 26045158 DOI: 10.1007/s00248-015-0635-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Accepted: 05/22/2015] [Indexed: 05/24/2023]
Abstract
This study investigates the effect of the organic loading rate (OLR) increase from 1.0 to 3.5 g VS L(-1) day(-1) at constant hydraulic retention time (HRT) of 35 days on anaerobic reactors' performance and microbial diversity during mesophilic anaerobic digestion of ammonium-rich chicken wastes in the absence/presence of zeolite. The effects of anaerobic process parameters on microbial community structure and dynamics were evaluated using a 16S ribosomal RNA gene-based pyrosequencing approach. Maximum 12 % of the total ammonia nitrogen (TAN) was efficiently removed by zeolite in the fixed zeolite reactor (day 87). In addition, volatile fatty acids (VFA) in the fixed zeolite reactor accumulated in lower concentrations at high OLR of 3.2-3.5 g VS L(-1) day(-1). Microbial communities in the fixed zeolite reactor and reactor without zeolite were dominated by various members of Bacteroidales and Methanobacterium sp. at moderate TAN and VFA levels. The increase of the OLR accompanied by TAN and VFA accumulation and increase in pH led to the predominance of representatives of the family Erysipelotrichaceae and genera Clostridium and Methanosarcina. Methanosarcina sp. reached relative abundances of 94 and 57 % in the fixed zeolite reactor and reactor without zeolite at the end of the experimental period, respectively. In addition, the diminution of Synergistaceae and Crenarchaeota and increase in the abundance of Acholeplasmataceae in parallel with the increase of TAN, VFA, and pH values were observed.
Collapse
Affiliation(s)
- Elvira E Ziganshina
- Department of Microbiology, Kazan (Volga Region) Federal University, Kazan, 420008, The Republic of Tatarstan, Russia
| | - Dmitry E Belostotskiy
- Department of Technologies, A. E. Arbuzov Institute of Organic and Physical Chemistry, Russian Academy of Sciences, Kazan, 420088, The Republic of Tatarstan, Russia
| | - Olga N Ilinskaya
- Department of Microbiology, Kazan (Volga Region) Federal University, Kazan, 420008, The Republic of Tatarstan, Russia
| | - Eugenia A Boulygina
- Laboratory of Omics Technologies, Kazan (Volga Region) Federal University, Kazan, 420008, The Republic of Tatarstan, Russia
| | - Tatiana V Grigoryeva
- Laboratory of Omics Technologies, Kazan (Volga Region) Federal University, Kazan, 420008, The Republic of Tatarstan, Russia
| | - Ayrat M Ziganshin
- Department of Microbiology, Kazan (Volga Region) Federal University, Kazan, 420008, The Republic of Tatarstan, Russia.
| |
Collapse
|
21
|
Differences in biomass degradation between newly isolated environmental strains of Clostridium thermocellum and heterogeneity in the size of the cellulosomal scaffoldin. Syst Appl Microbiol 2015; 38:424-32. [DOI: 10.1016/j.syapm.2015.06.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Revised: 06/05/2015] [Accepted: 06/05/2015] [Indexed: 11/21/2022]
|
22
|
Lindner J, Zielonka S, Oechsner H, Lemmer A. Effects of mechanical treatment of digestate after anaerobic digestion on the degree of degradation. BIORESOURCE TECHNOLOGY 2015; 178:194-200. [PMID: 25451773 DOI: 10.1016/j.biortech.2014.09.117] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Revised: 09/22/2014] [Accepted: 09/23/2014] [Indexed: 06/04/2023]
Abstract
The aim of this study was to increase the biogas production from different substrates by applying a mechanical treatment only to the non-degraded digestate after the fermentation process in order to feed it back into the process. To evaluate this approach, digestates were grounded with a ball mill for four different treatment time periods (0, 2, 5, 10 min) and then the effects on the particle size, volatile organic substances, methane yield and degradation kinetic were measured. A decrease of volatile fatty acids based on this treatment was not detected. The mechanical treatment caused in maximum to a triplication of the methane yield and to a quadruplicating of the daily methane production.
Collapse
Affiliation(s)
- Jonas Lindner
- University of Hohenheim, State Institute of Agricultural Engineering and Bioenergy, Garbenstraße 9, 70 599 Stuttgart, Germany.
| | - Simon Zielonka
- University of Hohenheim, State Institute of Agricultural Engineering and Bioenergy, Garbenstraße 9, 70 599 Stuttgart, Germany
| | - Hans Oechsner
- University of Hohenheim, State Institute of Agricultural Engineering and Bioenergy, Garbenstraße 9, 70 599 Stuttgart, Germany
| | - Andreas Lemmer
- University of Hohenheim, State Institute of Agricultural Engineering and Bioenergy, Garbenstraße 9, 70 599 Stuttgart, Germany
| |
Collapse
|
23
|
Lindner J, Zielonka S, Oechsner H, Lemmer A. Effect of different pH-values on process parameters in two-phase anaerobic digestion of high-solid substrates. ENVIRONMENTAL TECHNOLOGY 2015; 36:198-207. [PMID: 25413114 DOI: 10.1080/09593330.2014.941944] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
In many publications, primary fermentation is described as a limiting step in the anaerobic digestion of fibre-rich biomass [Eastman JA, Ferguson JF. Solubilization of particulacte carbon during the anaerobic digeston. J WPCF. 1981;53:352-366; Noike T, Endo G, Chang J, Yaguchi J, Matsumoto J. Characteristics of carbohydrate degradation and the rate-limiting step in anaerobic digestion. Biotechnol Bioeng. 1985;27:1482-1489; Arntz HJ, Stoppok E, Buchholz K. Anaerobic hydroysis of beet pulp-discontiniuous experiments. Biotechnol Lett. 1985;7:113-118]. The microorganisms of the primary fermentation process differ widely from the methanogenic microorganisms [Pohland FG, Ghosh S. Developments in anaerobic stabilization of organic wastes-the two-phase concept. Environ Lett. 1971;1:255-266]. To optimize the biogas process, a separation in two phases is suggested by many authors [Fox P, Pohland GK. Anaerobic treatment applications and fundamentals: substrate specificity during phase separation. Water Environ Res. 1994;66:716-724; Cohen A, Zoetemeyer RJ, van Deursen A, van Andel JG. Anaerobic digestion of glucose with separated acid production and methane formation. Water Res. 1979;13:571-580]. To carry out the examination, a two-phase laboratory-scale biogas plant was established, with a physical phase separation. In previous studies, the regulation of the pH-value during the acid formation was usually carried out by the addition of sodium hydroxide [Cohen A, Zoetemeyer RJ, van Deursen A, van Andel JG. Anaerobic digestion of glucose with separated acid production and methane formation. Water Res. 1979;13:571-580; Ueno Y, Tatara M, Fukui H, Makiuchi T, Goto M, Sode K. Production of hydrogen and methane from organic solid wastes by phase separation of anaerobic process. Bioresour Technol. 2007;98:1861-1865; Zoetemeyer RJ, van den Heuvel JC, Cohen A. pH influence on acidogenic dissimilation of glucose in an anaerobic digestor. Water Res. 1982;16:303-311]. A new technology without the use of additives was developed in which the pH-regulation is executed by the pH-dependent recycling of effluent from the anaerobic filter into the acidification reactor. During this investigation, the influence of the different target pH-values (5.5, 6.0, 7.0 and 7.5) on the degradation rate, the gas composition and the methane yield of the substrate maize silage was determined. With an increase in the target pH-value from 5.5 to 7.5, the acetic acid equivalent decreased by 88.1% and the chemical oxygen demand-concentration by 18.3% in the hydrolysate. In response, there was a 58% increase in the specific methane yield of the overall system. Contrary to earlier studies, a marked increase in biogas production and in substrate degradation was determined with increasing pH-values. However, these led to a successive approximation of a single-phase process. Based on these results, pH-values above 7.0 seem to be favourable for the digestion of fibre-rich substrates.
Collapse
Affiliation(s)
- Jonas Lindner
- a State Institute of Agricultural Engineering and Bioenergy, University of Hohenheim , Garbenstraße 9, Stuttgart 70599 , Germany
| | | | | | | |
Collapse
|
24
|
Ziganshina EE, Bagmanova AR, Khilyas IV, Ziganshin AM. Assessment of a biogas-generating microbial community in a pilot-scale anaerobic reactor. J Biosci Bioeng 2014; 117:730-6. [DOI: 10.1016/j.jbiosc.2013.11.013] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2013] [Revised: 09/25/2013] [Accepted: 11/18/2013] [Indexed: 10/25/2022]
|
25
|
Koeck DE, Zverlov VV, Liebl W, Schwarz WH. Comparative genotyping of Clostridium thermocellum strains isolated from biogas plants: genetic markers and characterization of cellulolytic potential. Syst Appl Microbiol 2014; 37:311-9. [PMID: 24951450 DOI: 10.1016/j.syapm.2014.05.006] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Revised: 05/09/2014] [Accepted: 05/12/2014] [Indexed: 10/25/2022]
Abstract
Clostridium thermocellum is among the most prevalent of known anaerobic cellulolytic bacteria. In this study, genetic and phenotypic variations among C. thermocellum strains isolated from different biogas plants were determined and different genotyping methods were evaluated on these isolates. At least two C. thermocellum strains were isolated independently from each of nine different biogas plants via enrichment on cellulose. Various DNA-based genotyping methods such as ribotyping, RAPD (Random Amplified Polymorphic DNA) and VNTR (Variable Number of Tandem Repeats) were applied to these isolates. One novel approach - the amplification of unknown target sequences between copies of a previously discovered Random Inserted Mobile Element (RIME) - was also tested. The genotyping method with the highest discriminatory power was found to be the amplification of the sequences between the insertion elements, where isolates from each biogas plant yielded a different band pattern. Cellulolytic potentials, optimal growth conditions and substrate spectra of all isolates were characterized to help identify phenotypic variations. Irrespective of the genotyping method used, the isolates from each individual biogas plant always exhibited identical patterns. This is suggestive of a single C. thermocellum strain exhibiting dominance in each biogas plant. The genotypic groups reflect the results of the physiological characterization of the isolates like substrate diversity and cellulase activity. Conversely, strains isolated across a range of biogas plants differed in their genotyping results and physiological properties. Both strains isolated from one biogas plant had the best specific cellulose-degrading properties and might therefore achieve superior substrate utilization yields in biogas fermenters.
Collapse
Affiliation(s)
- Daniela E Koeck
- Department of Microbiology, TechnischeUniversitätMünchen, Emil-Ramann-Str. 4, D-85350 Freising-Weihenstephan, Germany
| | - Vladimir V Zverlov
- Department of Microbiology, TechnischeUniversitätMünchen, Emil-Ramann-Str. 4, D-85350 Freising-Weihenstephan, Germany; Institute of Molecular Genetics, Russian Academy of Science, Kurchatov Sq. 2, 123182 Moscow, Russia
| | - Wolfgang Liebl
- Department of Microbiology, TechnischeUniversitätMünchen, Emil-Ramann-Str. 4, D-85350 Freising-Weihenstephan, Germany
| | - Wolfgang H Schwarz
- Department of Microbiology, TechnischeUniversitätMünchen, Emil-Ramann-Str. 4, D-85350 Freising-Weihenstephan, Germany.
| |
Collapse
|
26
|
Isolation and differentiation of methanogenic Archaea from mesophilic corn-fed on-farm biogas plants with special emphasis on the genus Methanobacterium. Appl Microbiol Biotechnol 2014; 98:5719-35. [DOI: 10.1007/s00253-014-5652-4] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2013] [Revised: 02/14/2014] [Accepted: 02/27/2014] [Indexed: 01/02/2023]
|
27
|
Synergism of glycoside hydrolase secretomes from two thermophilic bacteria cocultivated on lignocellulose. Appl Environ Microbiol 2014; 80:2592-601. [PMID: 24532065 DOI: 10.1128/aem.00295-14] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Two cellulolytic thermophilic bacterial strains, CS-3-2 and CS-4-4, were isolated from decayed cornstalk by the addition of growth-supporting factors to the medium. According to 16S rRNA gene-sequencing results, these strains belonged to the genus Clostridium and showed 98.87% and 98.86% identity with Clostridium stercorarium subsp. leptospartum ATCC 35414(T) and Clostridium cellulosi AS 1.1777(T), respectively. The endoglucanase and exoglucanase activities of strain CS-4-4 were approximately 3 to 5 times those of strain CS-3-2, whereas the β-glucosidase activity of strain CS-3-2 was 18 times higher than that of strain CS-4-4. The xylanase activity of strain CS-3-2 was 9 times that of strain CS-4-4, whereas the β-xylosidase activity of strain CS-4-4 was 27 times that of strain CS-3-2. The enzyme activities in spent cultures following cocultivation of the two strains with cornstalk as the substrate were much greater than those in pure cultures or an artificial mixture of samples, indicating synergism of glycoside hydrolase secretomes between the two strains. Quantitative measurement of the two strains in the cocultivation system indicated that strain CS-3-2 grew robustly during the initial stages, whereas strain CS-4-4 dominated the system in the late-exponential phase. Liquid chromatography-tandem mass spectrometry analysis of protein bands appearing in the native zymograms showed that ORF3880 and ORF3883 from strain CS-4-4 played key roles in the lignocellulose degradation process. Both these open reading frames (ORFs) exhibited endoglucanase and xylanase activities, but ORF3880 showed tighter adhesion to insoluble substrates at 4, 25, and 60°C owing to its five carbohydrate-binding modules (CBMs).
Collapse
|
28
|
Draft genome sequence of the cellulolytic Clostridium thermocellum wild-type strain BC1 playing a role in cellulosic biomass degradation. J Biotechnol 2013; 168:62-3. [PMID: 23968723 DOI: 10.1016/j.jbiotec.2013.08.011] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Accepted: 08/09/2013] [Indexed: 01/14/2023]
Abstract
The bacterium Clostridium thermocellum BC1, a thermophilic, anaerobic bacterium of the family Clostridiaceae, was isolated from a compost treatment site in Germany. It is able to grow efficiently on cellulose and cellodextrins. The draft genome sequence of C. thermocellum BC1 has been established and provides the genetic basis for application of this microorganism in thermophilic degradation of cellulosic biomass.
Collapse
|
29
|
Microbial community structure and dynamics during anaerobic digestion of various agricultural waste materials. Appl Microbiol Biotechnol 2013; 97:5161-74. [DOI: 10.1007/s00253-013-4867-0] [Citation(s) in RCA: 200] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2012] [Revised: 03/18/2013] [Accepted: 03/20/2013] [Indexed: 10/26/2022]
|
30
|
Complete Genome Sequence of Clostridium stercorarium subsp. stercorarium Strain DSM 8532, a Thermophilic Degrader of Plant Cell Wall Fibers. GENOME ANNOUNCEMENTS 2013; 1:e0007313. [PMID: 23516204 PMCID: PMC3593316 DOI: 10.1128/genomea.00073-13] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Clostridium stercorarium strain DSM 8532 is a thermophilic bacterium capable of efficiently degrading polysaccharides in plant biomass and converting the resulting sugars to ethanol and acetate. The complete genome sequence of 2.96 Mbp reveals a multitude of genes for hydrolytic enzymes and enables further study of the organism and its enzymes, and their exploitation for biotechnological processes.
Collapse
|
31
|
Weiß S, Lebuhn M, Andrade D, Zankel A, Cardinale M, Birner-Gruenberger R, Somitsch W, Ueberbacher BJ, Guebitz GM. Activated zeolite--suitable carriers for microorganisms in anaerobic digestion processes? Appl Microbiol Biotechnol 2013; 97:3225-38. [PMID: 23435898 DOI: 10.1007/s00253-013-4691-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2012] [Revised: 01/02/2013] [Accepted: 01/03/2013] [Indexed: 10/27/2022]
Abstract
Plant cell wall structures represent a barrier in the biodegradation process to produce biogas for combustion and energy production. Consequently, approaches concerning a more efficient de-polymerisation of cellulose and hemicellulose to monomeric sugars are required. Here, we show that natural activated zeolites (i.e. trace metal activated zeolites) represent eminently suitable mineral microhabitats and potential carriers for immobilisation of microorganisms responsible for anaerobic hydrolysis of biopolymers stabilising related bacterial and methanogenic communities. A strategy for comprehensive analysis of immobilised anaerobic populations was developed that includes the visualisation of biofilm formation via scanning electron microscopy and confocal laser scanning microscopy, community and fingerprint analysis as well as enzyme activity and identification analyses. Using SDS polyacrylamide gel electrophoresis, hydrolytical active protein bands were traced by congo red staining. Liquid chromatography/mass spectroscopy revealed cellulolytical endo- and exoglucanase (exocellobiohydrolase) as well as hemicellulolytical xylanase/mannase after proteolytic digestion. Relations to hydrolytic/fermentative zeolite colonisers were obtained by using single-strand conformation polymorphism analysis (SSCP) based on amplification of bacterial and archaeal 16S rRNA fragments. Thereby, dominant colonisers were affiliated to the genera Clostridium, Pseudomonas and Methanoculleus. The specific immobilisation on natural zeolites with functional microbes already colonising naturally during the fermentation offers a strategy to systematically supply the biogas formation process responsive to population dynamics and process requirements.
Collapse
Affiliation(s)
- S Weiß
- Institute of Environmental Biotechnology, Graz University of Technology, Petersgasse 12, 8010, Graz, Austria
| | | | | | | | | | | | | | | | | |
Collapse
|
32
|
Fernando E, Keshavarz T, Kyazze G. Simultaneous co-metabolic decolourisation of azo dye mixtures and bio-electricity generation under thermophillic (50 °C) and saline conditions by an adapted anaerobic mixed culture in microbial fuel cells. BIORESOURCE TECHNOLOGY 2013; 127:1-8. [PMID: 23131618 DOI: 10.1016/j.biortech.2012.09.065] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2012] [Revised: 09/17/2012] [Accepted: 09/18/2012] [Indexed: 06/01/2023]
Abstract
In this study, azo dye adapted mixed microbial consortium was used to effectively remove colour from azo dye mixtures and to simultaneously generate bio-electricity using microbial fuel cells (MFCs). Operating temperature (20-50 °C) and salinity (0.5-2.5%w/v) were varied during experiments. Reactor operation at 50 °C improved dye decolourisation and COD removal kinetic constants by approximately 2-fold compared to the kinetic constants at 30 °C. Decolourisation and COD removal kinetic constants remained high (0.28 h(-1) and 0.064 h(-1) respectively) at moderate salinity (1%w/v) but deteriorated approximately 4-fold when the salinity was raised to 2.5% (w/v). Molecular phylogenetic analysis of microbial cultures used in the study indicated that both un-acclimated and dye acclimated cultures from MFCs were predominantly comprised of Firmicutes bacteria. This study demonstrates the possibility of using adapted microbial consortia in MFCs for achieving efficient bio-decolourisation of complex azo dye mixtures and concomitant bio-electricity generation under industrially relevant conditions.
Collapse
Affiliation(s)
- Eustace Fernando
- Department of Molecular and Applied Biosciences, Applied Biotechnology Research Group, University of Westminster, 115 New Cavendish Street, London W1W 6UW, UK.
| | | | | |
Collapse
|
33
|
Krauss J, Zverlov VV, Schwarz WH. In vitro reconstitution of the complete Clostridium thermocellum cellulosome and synergistic activity on crystalline cellulose. Appl Environ Microbiol 2012; 78:4301-7. [PMID: 22522677 PMCID: PMC3370548 DOI: 10.1128/aem.07959-11] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2011] [Accepted: 03/30/2012] [Indexed: 11/20/2022] Open
Abstract
Artificial cellulase complexes active on crystalline cellulose were reconstituted in vitro from a native mix of cellulosomal enzymes and CipA scaffoldin. Enzymes containing dockerin modules for binding to the corresponding cohesin modules were prepared from culture supernatants of a C. thermocellum cipA mutant. They were reassociated to cellulosomes via dockerin-cohesin interaction. Recombinantly produced mini-CipA proteins with one to three cohesins either with or without the carbohydrate-binding module (CBM) and the complete CipA protein were used as the cellulosomal backbone. The binding between cohesins and dockerins occurred spontaneously. The hydrolytic activity against soluble and crystalline cellulosic compounds showed that the composition of the complex does not seem to be dependent on which CipA-derived cohesin was used for reconstitution. Binding did not seem to have an obvious local preference (equal binding to Coh1 and Coh6). The synergism on crystalline cellulose increased with an increasing number of cohesins in the scaffoldin. The in vitro-formed complex showed a 12-fold synergism on the crystalline substrate (compared to the uncomplexed components). The activity of reconstituted cellulosomes with full-size CipA reached 80% of that of native cellulosomes. Complexation on the surface of nanoparticles retained the activity of protein complexes and enhanced their stability. Partial supplementation of the native cellulosome components with three selected recombinant cellulases enhanced the activity on crystalline cellulose and reached that of the native cellulosome. This opens possibilities for in vitro complex reconstitution, which is an important step toward the creation of highly efficient engineered cellulases.
Collapse
Affiliation(s)
- Jan Krauss
- Department of Microbiology, Technische Universität München, Freising-Weihenstephan, Germany
| | - Vladimir V. Zverlov
- Department of Microbiology, Technische Universität München, Freising-Weihenstephan, Germany
- Institute of Molecular Genetics, Russian Academy of Science, Moscow, Russia
| | - Wolfgang H. Schwarz
- Department of Microbiology, Technische Universität München, Freising-Weihenstephan, Germany
| |
Collapse
|
34
|
Schönberg M, Linke B. The influence of the temperature regime on the formation of methane in a two-phase anaerobic digestion process. Eng Life Sci 2012. [DOI: 10.1002/elsc.201100062] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
|
35
|
Horn SJ, Estevez MM, Nielsen HK, Linjordet R, Eijsink VGH. Biogas production and saccharification of Salix pretreated at different steam explosion conditions. BIORESOURCE TECHNOLOGY 2011; 102:7932-6. [PMID: 21727002 DOI: 10.1016/j.biortech.2011.06.042] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2011] [Revised: 05/30/2011] [Accepted: 06/11/2011] [Indexed: 05/23/2023]
Abstract
Different steam explosion conditions were applied to Salix chips and the effect of this pretreatment was evaluated by running both enzymatic hydrolysis and biogas tests. Total enzymatic release of glucose and xylose increased with pretreatment harshness, with maximum values being obtained after pretreatment for 10 min at 210°C. Harsher pretreatment conditions did not increase glucose release, led to degradation of xylose and to formation of furfurals. Samples pretreated at 220 and 230°C initially showed low production of biogas, probably because of inhibitors produced during the pretreatment, but the microbial community was able to adapt and showed high final biogas production. Interestingly, final biogas yields correlated well with sugar yields after enzymatic hydrolysis, suggesting that at least in some cases a 24h enzymatic assay may be developed as a quick method to predict the effects of pretreatment of lignocellulosic biomass on biogas yields.
Collapse
Affiliation(s)
- Svein J Horn
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, P.O. Box 5003, N-1432 Ås, Norway.
| | | | | | | | | |
Collapse
|
36
|
The required characteristics of ensiled crops used as a feedstock for biogas production: a review. ACTA ACUST UNITED AC 2011. [DOI: 10.2478/v10146-011-0010-y] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The required characteristics of ensiled crops used as a feedstock for biogas production: a reviewMaize and grass silages are the main feedstock for anaerobic digestion in agricultural biogas plants. High-quality silage is necessary for high methane yields. Grasses should be cut and ensiled at leafy stages, until full heading, prior to an extensive lignification. Late ripening maize varieties should be harvested towards full ripening due to the increasing starch content in grains, and early to medium ripening varieties at the end of waxy ripeness. The substrate availability for methanogens is improved by fine chopping. Pretreatment processes of a thermal, chemical or biological nature attempting to disrupt lignocellulosic matter are economically demanding, including the application of enzyme hydrolysing structural polysaccharides. Application of lactic acid bacteria inoculants at ensiling seems to have an insignificant effect on methane yields. Some micronutrients necessary for methanogens growth are often deficient in the silages and particularly cobalt, nickel and iron should be supplemented. Maize silage has too low nitrogen content for methanogens growth. The high acidity of silage needs to be partially neutralised prior to anaerobic digestion.
Collapse
|
37
|
Gübitz GM, Gronauer A, Oechsner H. Editorial: Biogas science - State of the art and future perspectives. Eng Life Sci 2010. [DOI: 10.1002/elsc.201090027] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
|