1
|
Ling Chan H, Xu H, Zhou Y. External ceramic membrane contactor for in-situ H 2 assisted biogas upgrading. BIORESOURCE TECHNOLOGY 2024; 406:130981. [PMID: 38879053 DOI: 10.1016/j.biortech.2024.130981] [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: 04/19/2024] [Revised: 06/01/2024] [Accepted: 06/12/2024] [Indexed: 07/24/2024]
Abstract
Biological H2-assisted biogas upgrading has gained significant attention as an environmentally friendly substitute to common physico-chemical upgrading techniques, but is largely limited by the low solubility of H2. This study evaluated the design of a ceramic membrane contactor module for H2 injection. H2 dissolution was maintained at high efficiency by controlling gas supply and sludge recirculation rate, achieving a biogas quality of average 98.8% CH4 during the stable operation phase with a 108% increase in the CH4 production rate. This also outperforms conventional H2 injection using diffuser sparging which could only achieve a biogas quality of 84% CH4 content. Microbial community analysis found high Methanobacterium spp. abundance within the archaea at 95.2% at the end of the operation, allowing the dominance of the hydrogenotrophic methanogenesis pathway for high upgrading efficiencies. The system is a high-performance external membrane connector module coupled to common anaerobic digestion systems for biogas upgrading.
Collapse
Affiliation(s)
- Hui Ling Chan
- School of Civil and Environmental Engineering, Nanyang Technological University, 639798, Singapore
| | - Hui Xu
- Nanyang Environment and Water Research Institute, Nanyang Technological University, 637141, Singapore
| | - Yan Zhou
- School of Civil and Environmental Engineering, Nanyang Technological University, 639798, Singapore.
| |
Collapse
|
2
|
Wang C, Wei W, Wu L, Wang Y, Dai X, Ni BJ. A Novel Sustainable and Self-Sufficient Biotechnological Strategy for Directly Transforming Sewage Sludge into High-Value Liquid Biochemicals. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:12520-12531. [PMID: 38953238 DOI: 10.1021/acs.est.4c03165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/03/2024]
Abstract
Sewage sludge, as a carbon-rich byproduct of wastewater treatment, holds significant untapped potential as a renewable resource. Upcycling this troublesome waste stream represents great promise in addressing global escalating energy demands through its wide practice of biochemical recovery concurrently. Here, we propose a biotechnological concept to gain value-added liquid bioproducts from sewage sludge in a self-sufficient manner by directly transforming sludge into medium-chain fatty acids (MCFAs). Our findings suggest that yeast, a cheap and readily available commercial powder, would involve ethanol-type fermentation in chain elongation to achieve abundant MCFA production from sewage sludge using electron donors (i.e., ethanol) and acceptors (i.e., short-chain fatty acids) produced in situ. The enhanced abundance and transcriptional activity of genes related to key enzymes, such as butyryl-CoA dehydrogenase and alcohol dehydrogenase, affirm the robust capacity for the self-sustained production of MCFAs. This is indicative of an effective metabolic network established between yeast and anaerobic microorganisms within this innovative sludge fermentation framework. Furthermore, life cycle assessment and techno-economic analysis evidence the sustainability and economic competitiveness of this biotechnological strategy. Overall, this work provides insights into sewage sludge upgrading independent of additional carbon input, which can be applied in existing anaerobic sludge fermentation infrastructure as well as to develop new applications in a diverse range of industries.
Collapse
Affiliation(s)
- Chen Wang
- Water Research Centre, School of Civil and Environmental Engineering, The University of New South Wales, Sydney, NSW 2052, Australia
| | - Wei Wei
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, NSW 2007, Australia
| | - Lan Wu
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, NSW 2007, Australia
| | - Yun Wang
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China
| | - Xiaohu Dai
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China
| | - Bing-Jie Ni
- Water Research Centre, School of Civil and Environmental Engineering, The University of New South Wales, Sydney, NSW 2052, Australia
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, NSW 2007, Australia
| |
Collapse
|
3
|
Robazza A, Baleeiro FCF, Kleinsteuber S, Neumann A. Two-stage conversion of syngas and pyrolysis aqueous condensate into L-malate. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2024; 17:85. [PMID: 38907325 PMCID: PMC11191387 DOI: 10.1186/s13068-024-02532-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2024] [Accepted: 06/13/2024] [Indexed: 06/23/2024]
Abstract
Hybrid thermochemical-biological processes have the potential to enhance the carbon and energy recovery from organic waste. This work aimed to assess the carbon and energy recovery potential of multifunctional processes to simultaneously sequestrate syngas and detoxify pyrolysis aqueous condensate (PAC) for short-chain carboxylates production. To evaluate relevant process parameters for mixed culture co-fermentation of syngas and PAC, two identical reactors were run under mesophilic (37 °C) and thermophilic (55 °C) conditions at increasing PAC loading rates. Both the mesophilic and the thermophilic process recovered at least 50% of the energy in syngas and PAC into short-chain carboxylates. During the mesophilic syngas and PAC co-fermentation, methanogenesis was completely inhibited while acetate, ethanol and butyrate were the primary metabolites. Over 90% of the amplicon sequencing variants based on 16S rRNA were assigned to Clostridium sensu stricto 12. During the thermophilic process, on the other hand, Symbiobacteriales, Syntrophaceticus, Thermoanaerobacterium, Methanothermobacter and Methanosarcina likely played crucial roles in aromatics degradation and methanogenesis, respectively, while Moorella thermoacetica and Methanothermobacter marburgensis were the predominant carboxydotrophs in the thermophilic process. High biomass concentrations were necessary to maintain stable process operations at high PAC loads. In a second-stage reactor, Aspergillus oryzae converted acetate, propionate and butyrate from the first stage into L-malate, confirming the successful detoxification of PAC below inhibitory levels. The highest L-malate yield was 0.26 ± 2.2 molL-malate/molcarboxylates recorded for effluent from the mesophilic process at a PAC load of 4% v/v. The results highlight the potential of multifunctional reactors where anaerobic mixed cultures perform simultaneously diverse process roles, such as carbon fixation, wastewater detoxification and carboxylates intermediate production. The recovered energy in the form of intermediate carboxylates allows for their use as substrates in subsequent fermentative stages.
Collapse
Affiliation(s)
- Alberto Robazza
- Institute of Process Engineering in Life Sciences 2: Electro Biotechnology, Karlsruhe Institute of Technology - KIT, 76131, Karlsruhe, Germany
| | - Flávio C F Baleeiro
- Department of Microbial Biotechnology, Helmholtz Centre for Environmental Research - UFZ, 04318, Leipzig, Germany
| | - Sabine Kleinsteuber
- Department of Microbial Biotechnology, Helmholtz Centre for Environmental Research - UFZ, 04318, Leipzig, Germany
| | - Anke Neumann
- Institute of Process Engineering in Life Sciences 2: Electro Biotechnology, Karlsruhe Institute of Technology - KIT, 76131, Karlsruhe, Germany.
| |
Collapse
|
4
|
Undiandeye J, Gallegos D, Bonatelli ML, Kleinsteuber S, Bin-Hudari MS, Abdulkadir N, Stinner W, Sträuber H. Medium-chain carboxylates production from plant waste: kinetic study and effect of an enriched microbiome. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2024; 17:79. [PMID: 38867271 PMCID: PMC11167882 DOI: 10.1186/s13068-024-02528-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Accepted: 06/04/2024] [Indexed: 06/14/2024]
Abstract
BACKGROUND The need for addition of external electron donors such as ethanol or lactate impairs the economic viability of chain elongation (CE) processes for the production of medium-chain carboxylates (MCC). However, using feedstocks with inherent electron donors such as silages of waste biomass can improve the economics. Moreover, the use of an appropriate inoculum is critical to the overall efficiency of the CE process, as the production of a desired MCC can significantly be influenced by the presence or absence of specific microorganisms and their metabolic interactions. Beyond, it is necessary to generate data that can be used for reactor design, simulation and optimization of a given CE process. Such data can be obtained using appropriate mathematical models to predict the dynamics of the CE process. RESULTS In batch experiments using silages of sugar beet leaves, cassava leaves, and Elodea/wheat straw as substrates, caproate was the only MCC produced with maximum yields of 1.97, 3.48, and 0.88 g/kgVS, respectively. The MCC concentrations were accurately predicted with the modified Gompertz model. In a semi-continuous fermentation with ensiled sugar beet leaves as substrate and digestate from a biogas reactor as the sole inoculum, a prolonged lag phase of 7 days was observed for the production of MCC (C6-C8). The lag phase was significantly shortened by at least 4 days when an enriched inoculum was added to the system. With the enriched inoculum, an MCC yield of 93.67 g/kgVS and a productivity of 2.05 gMCC/L/d were achieved. Without the enriched inoculum, MCC yield and productivity were 43.30 g/kgVS and 0.95 gMCC/L/d, respectively. The higher MCC production was accompanied by higher relative abundances of Lachnospiraceae and Eubacteriaceae. CONCLUSIONS Ensiled waste biomass is a suitable substrate for MCC production using CE. For an enhanced production of MCC from ensiled sugar beet leaves, the use of an enriched inoculum is recommended for a fast process start and high production performance.
Collapse
Affiliation(s)
- Jerome Undiandeye
- Department of Biochemical Conversion, DBFZ Deutsches Biomasseforschungszentrum Gemeinnützige GmbH, 04347, Leipzig, Germany.
- Department of Chemical Engineering, University of Port Harcourt, PMB 5323, Port Harcourt, Nigeria.
| | - Daniela Gallegos
- Department of Biochemical Conversion, DBFZ Deutsches Biomasseforschungszentrum Gemeinnützige GmbH, 04347, Leipzig, Germany
| | - Maria L Bonatelli
- Department of Microbial Biotechnology, Helmholtz Centre for Environmental Research - UFZ, 04318, Leipzig, Germany
| | - Sabine Kleinsteuber
- Department of Microbial Biotechnology, Helmholtz Centre for Environmental Research - UFZ, 04318, Leipzig, Germany
| | - Mohammad Sufian Bin-Hudari
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research - UFZ, 04318, Leipzig, Germany
| | - Nafi'u Abdulkadir
- Research Unit for Comparative Microbiome Analysis, Helmholtz Munich, German Research Center for Environmental Health, 85764, Neuherberg, Germany
- Department of Microbiology, Sokoto State University, Sokoto, 852101, Nigeria
| | - Walter Stinner
- Department of Biochemical Conversion, DBFZ Deutsches Biomasseforschungszentrum Gemeinnützige GmbH, 04347, Leipzig, Germany
| | - Heike Sträuber
- Department of Microbial Biotechnology, Helmholtz Centre for Environmental Research - UFZ, 04318, Leipzig, Germany
| |
Collapse
|
5
|
O'Donnell C, Thorn C, Roskam E, Friel R, Kirwan SF, Waters SM, O'Flaherty V. Novel oxidising feed additives reduce in vitro methane emissions using the rumen simulation technique. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 926:171808. [PMID: 38508273 DOI: 10.1016/j.scitotenv.2024.171808] [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: 11/15/2023] [Revised: 03/14/2024] [Accepted: 03/16/2024] [Indexed: 03/22/2024]
Abstract
Enteric methane (CH4) produced by ruminant livestock is a potent greenhouse gas and represents significant energy loss for the animal. The novel application of oxidising compounds as antimethanogenic agents with future potential to be included in ruminant feeds, was assessed across two separate experiments in this study. Low concentrations of oxidising agents, namely urea hydrogen peroxide (UHP) with and without potassium iodide (KI), and magnesium peroxide (MgO2), were investigated for their effects on CH4 production, total gas production (TGP), volatile fatty acid (VFA) profiles, and nutrient disappearance in vitro using the rumen simulation technique. In both experiments, the in vitro diet consisted of 50:50 grass silage:concentrate on a dry matter basis. Treatment concentrations were based on the amount of oxygen delivered and expressed in terms of fold concentration. In Experiment 1, four treatments were tested (Control, 1× UHP + KI, 1× UHP, and 0.5× UHP + KI), and six treatments were assessed in Experiment 2 (Control, 0.5× UHP + KI, 0.5× UHP, 0.25× UHP + KI, 0.25× UHP, and 0.12× MgO2). All treatments in this study had a reducing effect on CH4 parameters. A dose-dependent reduction of TGP and CH4 parameters was observed, where treatments delivering higher levels of oxygen resulted in greater CH4 suppression. 1× UHP + KI reduced TGP by 28 % (p = 0.611), CH4% by 64 % (p = 0.075) and CH4 mmol/g digestible organic matter by 71 % (p = 0.037). 0.12× MgO2 reduced CH4 volume by 25 % (p > 0.05) without affecting any other parameters. Acetate-to-propionate ratios were reduced by treatments in both experiments (p < 0.01). Molar proportions of acetate and butyrate were reduced, while propionate and valerate were increased in UHP treatments. High concentrations of UHP affected the degradation of neutral detergent fibre in the forage substrate. Future in vitro work should investigate alternative slow-release oxygen sources aimed at prolonging CH4 suppression.
Collapse
Affiliation(s)
- Caroline O'Donnell
- Microbial Ecology Laboratory, School of Biological and Chemical Sciences, University of Galway, Galway, Ireland.
| | - Camilla Thorn
- GlasPort Bio Ltd, Business Innovation Centre, University of Galway, Galway, Ireland
| | - Emily Roskam
- Microbial Ecology Laboratory, School of Biological and Chemical Sciences, University of Galway, Galway, Ireland; Teagasc Animal and Bioscience Research Department, Teagasc Grange, Meath, Ireland
| | - Ruairi Friel
- GlasPort Bio Ltd, Business Innovation Centre, University of Galway, Galway, Ireland
| | - Stuart F Kirwan
- Teagasc Animal and Bioscience Research Department, Teagasc Grange, Meath, Ireland
| | - Sinéad M Waters
- Teagasc Animal and Bioscience Research Department, Teagasc Grange, Meath, Ireland; School of Biological and Chemical Sciences, University of Galway, Galway, Ireland
| | - Vincent O'Flaherty
- Microbial Ecology Laboratory, School of Biological and Chemical Sciences, University of Galway, Galway, Ireland; GlasPort Bio Ltd, Business Innovation Centre, University of Galway, Galway, Ireland.
| |
Collapse
|
6
|
Montecchio D, Gazzola G, Gallipoli A, Gianico A, Braguglia CM. Medium chain Fatty acids production from Food Waste via homolactic fermentation and lactate/ethanol elongation: Electron balance and thermodynamic assessment. WASTE MANAGEMENT (NEW YORK, N.Y.) 2024; 177:289-297. [PMID: 38359509 DOI: 10.1016/j.wasman.2024.01.049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Revised: 01/08/2024] [Accepted: 01/29/2024] [Indexed: 02/17/2024]
Abstract
This study explored the potential of Food Waste (FW) extract as a suitable substrate for Medium Chain Fatty Acids (MCFAs) production, in a single-phase reactor, where both fermentation and Chain Elongation (CE) processes occurred simultaneously. A continuous experiment was conducted with an Organic Loading Rate (OLR) = 20 gCOD L-1 d-1 and was fed in batch mode twice a week with pH = 6. In addition, four batch tests were performed, to assess the effects on the MCFAs production of caproate inhibition, hydrogen partial pressure (PH2) and different lactate/acetate ratios. Thermodynamics and electron flux were calculated to gain insights into the process pathways. Due to the presence of aminoacids, fermentation was mostly homolactic and both lactate and ethanol were produced as Electron Donors (EDs); the average MCFAs production efficiency was ∼ 12 %, although after 4 weeks the elongation process was halted, resulting in EDs accumulation. This occurred regardless of inoculum selection and the presence of caproate as a possible inhibitor, suggesting that EDs accumulation was due to the elongation process kinetics being slower than those of the fermentation step, thus calling for a longer Hydraulic Retention Time (HRT). It's worth noting that lactate was prevalently self-elongated to butyrate, whereas ethanol elongation only took place after lactate depletion, but was more efficient since it required other Electron Acceptors (EAs) such as butyrate, propionate or valerate. Moreover, the selected pH limited the acrylate pathway to a reasonable extent, whereas the high PH2 prevented both ethanol and lactate oxydation to acetate.
Collapse
Affiliation(s)
- Daniele Montecchio
- Istituto di Ricerca sulle Acque-CNR, Area della Ricerca RM1, 00015 Monterotondo, Roma, Italy.
| | - Giulio Gazzola
- Istituto di Ricerca sulle Acque-CNR, Area della Ricerca RM1, 00015 Monterotondo, Roma, Italy.
| | - Agata Gallipoli
- Istituto di Ricerca sulle Acque-CNR, Area della Ricerca RM1, 00015 Monterotondo, Roma, Italy.
| | - Andrea Gianico
- Istituto di Ricerca sulle Acque-CNR, Area della Ricerca RM1, 00015 Monterotondo, Roma, Italy.
| | - Camilla M Braguglia
- Istituto di Ricerca sulle Acque-CNR, Area della Ricerca RM1, 00015 Monterotondo, Roma, Italy.
| |
Collapse
|
7
|
Cao J, Guo Y, Luo X, Ge C, Hu Z, Wu L, Lv Y, Lin G, Yu D, Liu B. Interactions between enzyme preparations and trace element sources on growth performance and intestinal health of broiler chicks. Poult Sci 2023; 102:103124. [PMID: 37922857 PMCID: PMC10651683 DOI: 10.1016/j.psj.2023.103124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 09/12/2023] [Accepted: 09/13/2023] [Indexed: 11/07/2023] Open
Abstract
This experiment was conducted to explore the interactions between enzyme preparations and trace element sources on growth performance and intestinal health of broilers chicks. A total of 480 one-day-old healthy male yellow-feather broilers with similar weight were randomly arranged in a 2 × 2 factorial design with 2 kinds of compound trace element sources (inorganic [I] and organic [O] trace element supplemented with 80, 8, 60, 40, 0.15 mg/kg of Fe, Cu, Mn, Zn, and Se, respectively) and 2 levels of enzyme preparations (0 and 200 mg/kg). The 4 groups named I, O, IE, and OE with 6 replicates and 20 birds per replicate. The trail lasted for 28 days. Results showed that the average weight (ABW), average daily gain (ADG) of broilers in IE and OE groups significantly increased while the F/G significantly decreased as compared with group I and O (P < 0.05). Enzyme preparation supplementation, regardless of the trace element sources, significantly increased the duodenal and jejunal endogenous enzyme (e.g., Try and AACT) activity, and improved the morphology and jejunal barrier function evidenced by the increased villus height and MUC-2 mRNA expression (P < 0.05). Sequencing data manifested that enzyme preparations favorably modulated the cecal microflora by increasing bacterial diversity and abundance of short-chain fatty acid (SCFA)-producing bacteria (e.g., Anaerostipes, Anaerofusis, and Pygmaioactor), while decreasing the abundance of harmful bacteria (e.g., Desulfovibrio). Factorial analysis indicated that there were no interactions between enzyme preparation and trace element sources on growth performance and intestinal health of broiler chicks. In conclusion, dietary supplementation with enzyme preparations, regardless of the trace element sources, could enhance endogenous enzyme activity, improve intestinal morphology and barrier functions, and favorably modulate the cecal microflora, thereby improving the intestinal health and growth performance of broiler chicks.
Collapse
Affiliation(s)
- Jiuai Cao
- College of Animal Sciences, Zhejiang University, Hangzhou 310058, China
| | - Yanshan Guo
- College of Animal Sciences, Zhejiang University, Hangzhou 310058, China; Hainan Institute, Zhejiang University, Sanya 572025, China
| | - Xinyu Luo
- College of Animal Sciences, Zhejiang University, Hangzhou 310058, China
| | - Chaoyue Ge
- College of Animal Sciences, Zhejiang University, Hangzhou 310058, China
| | - Zhaoying Hu
- College of Animal Sciences, Zhejiang University, Hangzhou 310058, China
| | - Lianchi Wu
- College of Animal Sciences, Zhejiang University, Hangzhou 310058, China
| | - Yujie Lv
- College of Animal Sciences, Zhejiang University, Hangzhou 310058, China
| | - Gang Lin
- Research Department, Alltech, Beijing 100600, China
| | - Dongyou Yu
- College of Animal Sciences, Zhejiang University, Hangzhou 310058, China; Hainan Institute, Zhejiang University, Sanya 572025, China
| | - Bing Liu
- College of Animal Sciences, Zhejiang University, Hangzhou 310058, China.
| |
Collapse
|
8
|
Liu Q, Zhu Y, Li G, Guo T, Jin M, Xi D, Wang S, Liu X, Guo S, Liu H, Fan J, Liu R. Irisin ameliorates myocardial ischemia-reperfusion injury by modulating gut microbiota and intestinal permeability in rats. PLoS One 2023; 18:e0291022. [PMID: 37656700 PMCID: PMC10473488 DOI: 10.1371/journal.pone.0291022] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Accepted: 08/18/2023] [Indexed: 09/03/2023] Open
Abstract
Recently, myocardial ischemia-reperfusion (I/R) injury was suggested associated with intestinal flora. However, irisin has demonstrated beneficial effects on myocardial I/R injury, thus increasing interest in exploring its mechanism. Therefore, whether irisin interferes in gut microbiota and gut mucosal barrier during myocardial I/R injury was investigated in the present study. Irisin was found to reduce the infiltration of inflammatory cells and fracture in myocardial tissue, myocardial enzyme levels, and the myocardial infarction (MI) area. In addition, the data showed that irisin reverses I/R-induced gut dysbiosis as indicated by the decreased abundance of Actinobacteriota and the increased abundance of Firmicutes, and maintains intestinal barrier integrity, reduces metabolic endotoxemia, and inhibits the production of proinflammatory cytokines interleukin 1β (IL-1β), interleukin 6 (IL-6), and tumor necrosis factor α (TNF-α). Based on the results, irisin could be a good candidate for ameliorating myocardial I/R injury and associated diseases by alleviating gut dysbiosis, endothelial dysfunction and anti-inflammatory properties.
Collapse
Affiliation(s)
- Qingqing Liu
- LinFen Central Hospital, LinFen, China
- Linfen Key Laboratory of Basic and Clinical Research on Coronary Heart Disease, Linfen Clinical Medical Research Center, LinFen, China
| | - Yu Zhu
- LinFen Central Hospital, LinFen, China
- Linfen Key Laboratory of Basic and Clinical Research on Coronary Heart Disease, Linfen Clinical Medical Research Center, LinFen, China
- School of Sport Medicine and Rehabilitation, Beijing Sport University, Beijing, China
| | - Guangyao Li
- LinFen Central Hospital, LinFen, China
- Linfen Key Laboratory of Basic and Clinical Research on Coronary Heart Disease, Linfen Clinical Medical Research Center, LinFen, China
| | - Tiantian Guo
- LinFen Central Hospital, LinFen, China
- Linfen Key Laboratory of Basic and Clinical Research on Coronary Heart Disease, Linfen Clinical Medical Research Center, LinFen, China
| | - Mengtong Jin
- LinFen Central Hospital, LinFen, China
- Linfen Key Laboratory of Basic and Clinical Research on Coronary Heart Disease, Linfen Clinical Medical Research Center, LinFen, China
| | - Duan Xi
- LinFen Central Hospital, LinFen, China
| | | | - Xuezhi Liu
- LinFen Central Hospital, LinFen, China
- Linfen Key Laboratory of Basic and Clinical Research on Coronary Heart Disease, Linfen Clinical Medical Research Center, LinFen, China
- Department of Cardiovascular Surgery, Linfen Central Hospital, Linfen, China
| | - Shuming Guo
- LinFen Central Hospital, LinFen, China
- Linfen Key Laboratory of Basic and Clinical Research on Coronary Heart Disease, Linfen Clinical Medical Research Center, LinFen, China
| | - Hui Liu
- LinFen Central Hospital, LinFen, China
- Linfen Key Laboratory of Basic and Clinical Research on Coronary Heart Disease, Linfen Clinical Medical Research Center, LinFen, China
- Department of Cardiovascular Surgery, Linfen Central Hospital, Linfen, China
| | - Jiamao Fan
- LinFen Central Hospital, LinFen, China
- Linfen Key Laboratory of Basic and Clinical Research on Coronary Heart Disease, Linfen Clinical Medical Research Center, LinFen, China
- Department of Cardiology, Linfen Central Hospital, Linfen, China
| | - Ronghua Liu
- LinFen Central Hospital, LinFen, China
- Linfen Key Laboratory of Basic and Clinical Research on Coronary Heart Disease, Linfen Clinical Medical Research Center, LinFen, China
| |
Collapse
|
9
|
Sabbe K, D'Haen L, Boon N, Ganigué R. Predicting the performance of chain elongating microbiomes through flow cytometric fingerprinting. WATER RESEARCH 2023; 243:120323. [PMID: 37459796 DOI: 10.1016/j.watres.2023.120323] [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: 03/23/2023] [Revised: 06/29/2023] [Accepted: 07/06/2023] [Indexed: 09/07/2023]
Abstract
As part of the circular bio-economy paradigm shift, waste management and valorisation practices have moved away from sanitation and towards the production of added-value compounds. Recently, the development of mixed culture bioprocess for the conversion of waste(water) to platform chemicals, such as medium chain carboxylic acids, has attracted significant interest. Often, the microbiology of these novel bioprocesses is less diverse and more prone to disturbances, which can lead to process failure. This issue can be tackled by implementing an advanced monitoring strategy based on the microbiology of the process. In this study, flow cytometry was used to monitor the microbiology of lactic acid chain elongation for the production of caproic acid, and assess its performance both qualitatively and quantitatively. Two continuous stirred tank reactors for chain elongation were monitored flow cytometrically for over 336 days. Through community typing, four specific community types could be identified and correlated to both a specific functionality and genotypic diversity. Additionally, the machine-learning algorithms trained in this study demonstrated the ability to predict production rates of, amongst others, caproic acid with high accuracy in the present (R² > 0.87) and intermediate accuracy in the near future (R² > 0.63). The identification of specific community types and the development of predictive algorithms form the basis of advanced bioprocess monitoring based on flow cytometry, and have the potential to improve bioprocess control and optimization, leading to better product quality and yields.
Collapse
Affiliation(s)
- Kevin Sabbe
- Center for Microbial Ecology and Technology (CMET), Ghent University, Coupure Links 653, 9000 Ghent, Belgium; Center for Advanced Process Technology for Urban Resource Recovery (CAPTURE), Frieda Saeysstraat 1, 9052 Ghent, Belgium
| | - Liese D'Haen
- Center for Microbial Ecology and Technology (CMET), Ghent University, Coupure Links 653, 9000 Ghent, Belgium
| | - Nico Boon
- Center for Microbial Ecology and Technology (CMET), Ghent University, Coupure Links 653, 9000 Ghent, Belgium; Center for Advanced Process Technology for Urban Resource Recovery (CAPTURE), Frieda Saeysstraat 1, 9052 Ghent, Belgium
| | - Ramon Ganigué
- Center for Microbial Ecology and Technology (CMET), Ghent University, Coupure Links 653, 9000 Ghent, Belgium; Center for Advanced Process Technology for Urban Resource Recovery (CAPTURE), Frieda Saeysstraat 1, 9052 Ghent, Belgium.
| |
Collapse
|
10
|
Dahiya S, Mohan SV. Co-fermenting lactic acid and glucose towards caproic acid production. CHEMOSPHERE 2023; 328:138491. [PMID: 36963586 DOI: 10.1016/j.chemosphere.2023.138491] [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: 08/25/2022] [Revised: 02/20/2023] [Accepted: 03/21/2023] [Indexed: 06/18/2023]
Abstract
The functional role of lactate (HLac), as a co-substrate along with glucose (Glu) as well as an electron donor for the synthesis of caproic acid (HCa), a medium chain fatty acid (MCFAs) was studied. A varied HLac and Glu ratios were thus investigated in fed-batch anaerobic reactors (R1-R5) operated at pH 6 with a heat-treated anaerobic consortium. R1 and R5 were noted as controls and operated with sole Glu and HLac, respectively. Strategically, ethanol (HEth) was additionally supplemented as co-electron donor after the production of short chain carboxylic acids (SCCAs) for chain elongation in all the reactors. The reactor operated with HLac and Glu in a ratio of 0.25:0.75 (1.25 g/L (HLac) and 3.75 g/L (Glu)) showed the highest HCa production of 1.86 g/L. R5 operated with solely HLac yielded propionic acid (HPr) as the major product which further led to the higher valeric acid (HVa) production of 1.1 g/L within the reactor. Butyric acid (HBu) was observed in R1, which used Glu as carbon source alone indicating the importance of HLac as electron co-donor. Clostridium observed as the most dominant genera in shotgun metagenome sequencing in R2 and R3, the reactors that produced the highest HCa in comparison to other studied reactors. The study thus provided insight into the importance of substrate and electron donor and their supplementation strategies during the production of MCFAs.
Collapse
Affiliation(s)
- Shikha Dahiya
- Bioengineering and Environmental Science Lab, Department of Energy and Environmental Engineering, CSIR-Indian Institute of Chemical Technology (CSIR-IICT), Hyderabad, 500 007, India; Academy of Scientific & Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - S Venkata Mohan
- Bioengineering and Environmental Science Lab, Department of Energy and Environmental Engineering, CSIR-Indian Institute of Chemical Technology (CSIR-IICT), Hyderabad, 500 007, India; Academy of Scientific & Innovative Research (AcSIR), Ghaziabad, 201002, India.
| |
Collapse
|
11
|
Henry GBL, Awedem Wobiwo F, Isenborghs A, Nicolay T, Godin B, Stenuit BA, Gerin PA. A specific H 2/CO 2 consumption molar ratio of 3 as a signature for the chain elongation of carboxylates from brewer's spent grain acidogenesis. Front Bioeng Biotechnol 2023; 11:1165197. [PMID: 37324420 PMCID: PMC10267453 DOI: 10.3389/fbioe.2023.1165197] [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: 02/13/2023] [Accepted: 05/09/2023] [Indexed: 06/17/2023] Open
Abstract
Brewer's spent grain (BSG) is an undervalorized organic feedstock residue composed of fermentable macromolecules, such as proteins, starch, and residual soluble carbohydrates. It also contains at least 50% (as dry weight) of lignocellulose. Methane-arrested anaerobic digestion is one of the promising microbial technologies to valorize such complex organic feedstock into value-added metabolic intermediates, such as ethanol, H2, and short-chain carboxylates (SCC). Under specific fermentation conditions, these intermediates can be microbially transformed into medium-chain carboxylates through a chain elongation pathway. Medium-chain carboxylates are of great interest as they can be used as bio-based pesticides, food additives, or components of drug formulations. They can also be easily upgraded by classical organic chemistry into bio-based fuels and chemicals. This study investigates the production potential of medium-chain carboxylates driven by a mixed microbial culture in the presence of BSG as an organic substrate. Because the conversion of complex organic feedstock to medium-chain carboxylates is limited by the electron donor content, we assessed the supplementation of H2 in the headspace to improve the chain elongation yield and increase the production of medium-chain carboxylates. The supply of CO2 as a carbon source was tested as well. The additions of H2 alone, CO2 alone, and both H2 and CO2 were compared. The exogenous supply of H2 alone allowed CO2 produced during acidogenesis to be consumed and nearly doubled the medium-chain carboxylate production yield. The exogenous supply of CO2 alone inhibited the whole fermentation. The supplementation of both H2 and CO2 allowed a second elongation phase when the organic feedstock was exhausted, which increased the medium-chain carboxylate production by 285% compared to the N2 reference condition. Carbon- and electron-equivalent balances, and the stoichiometric ratio of 3 observed for the consumed H2/CO2, suggest an H2- and CO2-driven second elongation phase, converting SCC to medium-chain carboxylates without an organic electron donor. The thermodynamic assessment confirmed the feasibility of such elongation.
Collapse
Affiliation(s)
- Grégoire B. L. Henry
- Laboratory of Bioengineering and Biorefining, Earth and Life Institute—Applied Microbiology, Université Catholique de Louvain, Louvain-La-Neuve, Belgium
| | - Florent Awedem Wobiwo
- Laboratory of Bioengineering and Biorefining, Earth and Life Institute—Applied Microbiology, Université Catholique de Louvain, Louvain-La-Neuve, Belgium
| | - Arnaud Isenborghs
- Laboratory of Bioengineering and Biorefining, Earth and Life Institute—Applied Microbiology, Université Catholique de Louvain, Louvain-La-Neuve, Belgium
| | - Thomas Nicolay
- Laboratory of Bioengineering and Biorefining, Earth and Life Institute—Applied Microbiology, Université Catholique de Louvain, Louvain-La-Neuve, Belgium
| | - Bruno Godin
- Walloon Agricultural Research Center (CRA-W), Valorization of Agricultural Products Department, Gembloux, Belgium
| | - Benoit A. Stenuit
- Laboratory of Bioengineering and Biorefining, Earth and Life Institute—Applied Microbiology, Université Catholique de Louvain, Louvain-La-Neuve, Belgium
| | - Patrick A. Gerin
- Laboratory of Bioengineering and Biorefining, Earth and Life Institute—Applied Microbiology, Université Catholique de Louvain, Louvain-La-Neuve, Belgium
| |
Collapse
|
12
|
Li L, Liu C, Xu L, Zhuang H, He J, He Q, Zhang J. Acclimation of anaerobic fermentation microbiome with acetate and ethanol for chain elongation and the biochemical response. CHEMOSPHERE 2023; 320:138083. [PMID: 36754309 DOI: 10.1016/j.chemosphere.2023.138083] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Revised: 01/10/2023] [Accepted: 02/05/2023] [Indexed: 06/18/2023]
Abstract
Medium chain fatty acids (MCFAs) production is a promising method for resource recovery from organic wastes. In this study, the microbial community structure shift along the long-term acclimation experiment and the concomitant effect of H2 level on chain elongation performance was investigated. Chain elongation microbiome could be rapidly acclimated from traditional anaerobic fermentation consortia. Genera Caproiciproducens, Clostridium sensu stricto 12, Rummeliibacillus and Oscillibacter was found to be dominant during the operation. The H2 was accumulated in the headspace by increasing the ethanol input, which inhibited oxidation of caproate and butyrate immediately, while its inhibition effect on chain elongation was delayed. H2 level in the headspace was positively correlated to the MCFAs production related bacteria. However, too much H2 accumulated might be suppressive for MCFAs production in the long term. It might result from the thermodynamic barrier for discarding excess reducing equivalents under high H2 level, which further gave rise to ethanol accumulation in this system.
Collapse
Affiliation(s)
- Lin Li
- College of Environment and Ecology, Chongqing University, Chongqing 400044, China; State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Chang Liu
- College of Environment and Ecology, Chongqing University, Chongqing 400044, China
| | - Linji Xu
- College of Environment and Ecology, Chongqing University, Chongqing 400044, China.
| | - Huichuan Zhuang
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
| | - Junguo He
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China; School of Civil Engineering, Guangzhou University, Guangzhou 510006, China.
| | - Qiang He
- College of Environment and Ecology, Chongqing University, Chongqing 400044, China
| | - Jie Zhang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| |
Collapse
|
13
|
Shrestha S, Xue S, Raskin L. Competitive Reactions during Ethanol Chain Elongation Were Temporarily Suppressed by Increasing Hydrogen Partial Pressure through Methanogenesis Inhibition. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:3369-3379. [PMID: 36790331 PMCID: PMC9979639 DOI: 10.1021/acs.est.2c09014] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 01/16/2023] [Accepted: 01/27/2023] [Indexed: 05/29/2023]
Abstract
Organic waste streams can be converted into high-value platform chemicals such as medium-chain carboxylic acids (MCCAs) using mixed microbial communities via chain elongation. However, the heterogeneity of waste streams and the use of complex microbial communities can lead to undesirable reactions, thus decreasing process efficiency. We explored suppressing excessive ethanol oxidation to acetate (EEO) by increasing the hydrogen partial pressure (PH2) through hydrogenotrophic methanogenesis inhibition by periodically adding 2-bromoethanesulfonate (2-BES) to an MCCA-producing bioreactor to reach 10 mM of 2-BES upon addition. The bioreactor was fed with pretreated food waste and brewery waste containing high concentrations of short-chain carboxylic acids and ethanol, respectively. While 2-BES addition initially reduced EEO, some methanogens (Methanobrevibacter spp.) persisted and resistant populations were selected over time. Besides changing the methanogenic community structure, adding 2-BES also changed the bacterial community structure due to its impact on PH2. While we demonstrated that PH2 could be manipulated using 2-BES to control EEO, methods that do not require the addition of a chemical inhibitor should be explored to maintain optimum PH2 for long-term suppression of EEO.
Collapse
Affiliation(s)
| | - Siqi Xue
- Department of Civil and Environmental
Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Lutgarde Raskin
- Department of Civil and Environmental
Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
| |
Collapse
|
14
|
Sakarika M, Regueira A, Rabaey K, Ganigué R. Thermophilic caproic acid production from grass juice by sugar-based chain elongation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 860:160501. [PMID: 36436634 DOI: 10.1016/j.scitotenv.2022.160501] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 11/04/2022] [Accepted: 11/21/2022] [Indexed: 06/16/2023]
Abstract
Medium chain carboxylic acids (MCCA) such as caproic acid have a plethora of applications, ranging from food additives to bioplastics. MCCA can be produced via microbial chain elongation using waste and side-streams as substrates, a process that can be more sustainable than conventional production routes. Most chain elongation studies have focused on mesophilic conditions, with only two recent studies hinting at the possibility of thermophilic chain elongation, but a systematic study of its mechanisms is lacking. Here, we investigated thermophilic chain elongation from grass juice, to understand the effect of key operational parameters (pH, temperature, substrate) on the process performance and to establish the key microbial genera and their role in the system. The genus Caproiciproducens was identified as responsible for thermophilic chain elongation, and caproic acid production was most favorable at pH 6.0 and 50 °C among the conditions tested, reaching an average concentration of 3.4 g/L. Batch experiments showed that the substrate for caproic acid production were glucose and xylose, while lactic acid led to the production of only butyric acid. Fed-batch experiments showed that substrate availability and the presence of caproic acid in the system play a major role in shaping the profile of thermophilic chain elongation. The increase of the total sugar concentration by glucose addition (without changing the organic load) during continuous operation led to a microbial community dominated (75 %) by Caproiciproducens and increased by 76 % the final average caproic acid concentration to 6.0 g/L (13 gCOD/L) which represented 32 % (g/g) of the total carboxylic acids. The highest concentration achieved was 7.2 g/L (day 197) which is the highest concentration reported under thermophilic conditions thus far. The results of this work pave the way to the potential development of thermophilic systems for upgrading various underexplored abundant and cheap sugar-rich side-streams to caproic acid.
Collapse
Affiliation(s)
- Myrsini Sakarika
- Center for Microbial Ecology and Technology (CMET), Faculty of Bioscience Engineering Ghent University, Coupure Links 653, 9000 Ghent, Belgium; Center for Advanced Process Technology for Urban Resource recovery (CAPTURE), Frieda Saeysstraat, 9052 Ghent, Belgium
| | - Alberte Regueira
- Center for Microbial Ecology and Technology (CMET), Faculty of Bioscience Engineering Ghent University, Coupure Links 653, 9000 Ghent, Belgium; Center for Advanced Process Technology for Urban Resource recovery (CAPTURE), Frieda Saeysstraat, 9052 Ghent, Belgium; Cross-disciplinary Research in Environmental Technologies (CRETUS), Department of Chemical Engineering, Universidade de Santiago de Compostela, Spain
| | - Korneel Rabaey
- Center for Microbial Ecology and Technology (CMET), Faculty of Bioscience Engineering Ghent University, Coupure Links 653, 9000 Ghent, Belgium; Center for Advanced Process Technology for Urban Resource recovery (CAPTURE), Frieda Saeysstraat, 9052 Ghent, Belgium
| | - Ramon Ganigué
- Center for Microbial Ecology and Technology (CMET), Faculty of Bioscience Engineering Ghent University, Coupure Links 653, 9000 Ghent, Belgium; Center for Advanced Process Technology for Urban Resource recovery (CAPTURE), Frieda Saeysstraat, 9052 Ghent, Belgium.
| |
Collapse
|
15
|
Baleeiro FCF, Varchmin L, Kleinsteuber S, Sträuber H, Neumann A. Formate-induced CO tolerance and methanogenesis inhibition in fermentation of syngas and plant biomass for carboxylate production. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2023; 16:26. [PMID: 36805806 PMCID: PMC9936662 DOI: 10.1186/s13068-023-02271-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Accepted: 01/29/2023] [Indexed: 02/19/2023]
Abstract
BACKGROUND Production of monocarboxylates using microbial communities is highly dependent on local and degradable biomass feedstocks. Syngas or different mixtures of H2, CO, and CO2 can be sourced from biomass gasification, excess renewable electricity, industrial off-gases, and carbon capture plants and co-fed to a fermenter to alleviate dependence on local biomass. To understand the effects of adding these gases during anaerobic fermentation of plant biomass, a series of batch experiments was carried out with different syngas compositions and corn silage (pH 6.0, 32 °C). RESULTS Co-fermentation of syngas with corn silage increased the overall carboxylate yield per gram of volatile solids (VS) by up to 29% (0.47 ± 0.07 g gVS-1; in comparison to 0.37 ± 0.02 g gVS-1 with a N2/CO2 headspace), despite slowing down biomass degradation. Ethylene and CO exerted a synergistic effect in preventing methanogenesis, leading to net carbon fixation. Less than 12% of the electrons were misrouted to CH4 when either 15 kPa CO or 5 kPa CO + 1.5 kPa ethylene was used. CO increased the selectivity to acetate and propionate, which accounted for 85% (electron equivalents) of all products at 49 kPa CO, by favoring lactic acid bacteria and actinobacteria over n-butyrate and n-caproate producers. Inhibition of n-butyrate and n-caproate production by CO happened even when an inoculum preacclimatized to syngas and lactate was used. Intriguingly, the effect of CO on n-butyrate and n-caproate production was reversed when formate was present in the broth. CONCLUSIONS The concept of co-fermenting syngas and plant biomass shows promise in three aspects: by making anaerobic fermentation a carbon-fixing process, by increasing the yields of short-chain carboxylates (propionate and acetate), and by minimizing electron losses to CH4. Moreover, a model was proposed for how formate can alleviate CO inhibition in certain acidogenic bacteria. Testing the fermentation of syngas and plant biomass in a continuous process could potentially improve selectivity to n-butyrate and n-caproate by enriching chain-elongating bacteria adapted to CO and complex biomass.
Collapse
Affiliation(s)
- Flávio C. F. Baleeiro
- grid.7492.80000 0004 0492 3830Department of Environmental Microbiology, Helmholtz Centre for Environmental Research – UFZ, Leipzig, Germany ,grid.7892.40000 0001 0075 5874Technical Biology, Institute of Process Engineering in Life Science, Karlsruhe Institute of Technology – KIT, Karlsruhe, Germany
| | - Lukas Varchmin
- grid.7892.40000 0001 0075 5874Technical Biology, Institute of Process Engineering in Life Science, Karlsruhe Institute of Technology – KIT, Karlsruhe, Germany
| | - Sabine Kleinsteuber
- grid.7492.80000 0004 0492 3830Department of Environmental Microbiology, Helmholtz Centre for Environmental Research – UFZ, Leipzig, Germany
| | - Heike Sträuber
- grid.7492.80000 0004 0492 3830Department of Environmental Microbiology, Helmholtz Centre for Environmental Research – UFZ, Leipzig, Germany
| | - Anke Neumann
- Technical Biology, Institute of Process Engineering in Life Science, Karlsruhe Institute of Technology - KIT, Karlsruhe, Germany.
| |
Collapse
|
16
|
He Y, Cassarini C, Lens PN. Enrichment of homoacetogens converting H 2/CO 2 into acids and ethanol and simultaneous methane production. Eng Life Sci 2022; 23:e2200027. [PMID: 36751471 PMCID: PMC9893759 DOI: 10.1002/elsc.202200027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 08/06/2022] [Accepted: 11/05/2022] [Indexed: 12/12/2022] Open
Abstract
An anaerobic granular sludge was enriched to utilize H2/CO2 in a continuous gas-fed up-flow anaerobic sludge reactor by applying operating conditions expected to produce acetic acid, butyric acid, and ethanol. Three stages of fermentation were found: Stage I with acetic acid accumulation with the highest concentration of 35 mM along with a pH decrease from initial 6 to 4.5. In Stage II, H2/CO2 was replaced by 100% H2 to induce solventogenesis, whereas butyric acid was produced with the highest concentration of 2.5 mM. At stage III with 10 µM tungsten (W) addition, iso-valeric acid, valeric acid, and caproic acid were produced at pH 4.5-5.0. In the batch tests inoculated with the enriched sludge taken from the bioreactor (day 70), however, methane production occurred at pH 6. Exogenous 15 mM acetate addition enhanced both the H2 and CO2 consumption rate compared to exogenous 10, 30, and 45 mM acetate by the enriched sludge. Exogenous acetate was failed to be converted to ethanol using H2 as electron donor by the enriched acetogens.
Collapse
Affiliation(s)
- Yaxue He
- National University of Ireland GalwayGalwayIreland
| | | | | |
Collapse
|
17
|
Baleeiro FCF, Raab J, Kleinsteuber S, Neumann A, Sträuber H. Mixotrophic chain elongation with syngas and lactate as electron donors. Microb Biotechnol 2022; 16:322-336. [PMID: 36378491 PMCID: PMC9871530 DOI: 10.1111/1751-7915.14163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Revised: 10/14/2022] [Accepted: 10/17/2022] [Indexed: 11/16/2022] Open
Abstract
Feeding microbial communities with both organic and inorganic substrates can improve sustainability and feasibility of chain elongation processes. Sustainably produced H2 , CO2 , and CO can be co-fed to microorganisms as a source for acetyl-CoA, while a small amount of an ATP-generating organic substrate helps overcome the kinetic hindrances associated with autotrophic carboxylate production. Here, we operated two semi-continuous bioreactor systems with continuous recirculation of H2 , CO2 , and CO while co-feeding an organic model feedstock (lactate and acetate) to understand how a mixotrophic community is shaped during carboxylate production. Contrary to the assumption that H2 , CO2 , and CO support chain elongation via ethanol production in open cultures, significant correlations (p < 0.01) indicated that relatives of Clostridium luticellarii and Eubacterium aggregans produced carboxylates (acetate to n-caproate) while consuming H2 , CO2 , CO, and lactate themselves. After 100 days, the enriched community was dominated by these two bacteria coexisting in cyclic dynamics shaped by the CO partial pressure. Homoacetogenesis was strongest when the acetate concentration was low (3.2 g L-1 ), while heterotrophs had the following roles: Pseudoramibacter, Oscillibacter, and Colidextribacter contributed to n-caproate production and Clostridium tyrobutyricum and Acidipropionibacterium spp. grew opportunistically producing n-butyrate and propionate, respectively. The mixotrophic chain elongation community was more efficient in carboxylate production compared with the heterotrophic one and maintained average carbon fixation rates between 0.088 and 1.4 g CO2 equivalents L-1 days-1 . The extra H2 and CO consumed routed 82% more electrons to carboxylates and 50% more electrons to carboxylates longer than acetate. This study shows for the first time long-term, stable production of short- and medium-chain carboxylates with a mixotrophic community.
Collapse
Affiliation(s)
- Flávio C. F. Baleeiro
- Department of Environmental MicrobiologyHelmholtz Centre for Environmental Research – UFZLeipzigGermany,Technical Biology, Institute of Process Engineering in Life ScienceKarlsruhe Institute of Technology – KITKarlsruheGermany
| | - Jana Raab
- Department of Environmental MicrobiologyHelmholtz Centre for Environmental Research – UFZLeipzigGermany
| | - Sabine Kleinsteuber
- Department of Environmental MicrobiologyHelmholtz Centre for Environmental Research – UFZLeipzigGermany
| | - Anke Neumann
- Technical Biology, Institute of Process Engineering in Life ScienceKarlsruhe Institute of Technology – KITKarlsruheGermany
| | - Heike Sträuber
- Department of Environmental MicrobiologyHelmholtz Centre for Environmental Research – UFZLeipzigGermany
| |
Collapse
|
18
|
Wu L, Wei W, Liu X, Wang D, Ni BJ. Potentiality of recovering bioresource from food waste through multi-stage Co-digestion with enzymatic pretreatment. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 319:115777. [PMID: 35982572 DOI: 10.1016/j.jenvman.2022.115777] [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: 04/13/2022] [Revised: 07/15/2022] [Accepted: 07/15/2022] [Indexed: 06/15/2023]
Abstract
Food waste (FW) is not only a major social, nutritional and environmental issue, but also an underutilized resource with significant energy, which has not been fully explored currently. Considering co-digestion can adjust carbon to nitrogen ratio (C/N) of the feedstock and improve the synergetic interactions among microorganisms, anaerobic co-digestion (AnCoD) is then becoming an emerging approach to achieve higher energy recovery from FW while ensuring the stability of the system. To obtain higher economic gain from such biodegradable wastes, increasing attention has been paid on optimizing the system configuration or applying enzymatic hydrolysis before digesting FW. A better understanding on the potentiality of correlating enzymatic pretreatment and AnCoD operated in various system configuration would enhance the bioresource recovery from FW and increase revenue through treating this organic waste. Specifically, the biobased chemicals outputs from FW-related co-digestion system with different configuration were firstly compared in this review. A deep discussion concerning the challenges for achieving bioresources recovery from FW co-digestion systems with enzymatic pretreatment was then given. Recommendations for future studies regarding FW co-digestion were then proposed at last.
Collapse
Affiliation(s)
- Lan Wu
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, NSW, 2007, Australia
| | - Wei Wei
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, NSW, 2007, Australia
| | - Xuran Liu
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, NSW, 2007, Australia
| | - Dongbo Wang
- Key Laboratory of Environmental Biology and Pollution Control, College of Environmental Science and Engineering, Hunan University, Changsha, 410082, China.
| | - Bing-Jie Ni
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, NSW, 2007, Australia.
| |
Collapse
|
19
|
Yin Y, Hu Y, Wang J. Co-fermentation of sewage sludge and lignocellulosic biomass for production of medium-chain fatty acids. BIORESOURCE TECHNOLOGY 2022; 361:127665. [PMID: 35872272 DOI: 10.1016/j.biortech.2022.127665] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Revised: 07/17/2022] [Accepted: 07/18/2022] [Indexed: 06/15/2023]
Abstract
Medium-chain fatty acids (MCFAs) production from sewage sludge and lignocellulosic biomass (fallen leaves and grass) was explored. Co-fermentation of sludge and lignocellulosic biomass significantly accelerated the caproate production and promoted the longer-chain MCFAs formation. Co-fermentation of sludge and grass achieved the highest caproate production of 89.50 mmol C/L, which was 18.04 % and 41.73 % higher than the mono-fermentation of grass and sludge, respectively. Co-fermentation of sludge and leaves produced 63.80 mmol C/L caproate, which was 11.09 % and 1.03 % higher than the mono-fermentation of leaves and sludge, respectively. Microbial analysis showed that co-fermentation enriched CE microbes like genus Clostridium_sensu_stricto_13, Caprocipiproducens, Terrisporpbacter and Praraclostridium, and suppressed the competitive microbes like genus norank_f_Caldilineaceae and Desulfomicrobium. Functional enzymes analysis revealed that co-fermentation of sludge and leaves promoted MCFAs production through strengthening reverse β oxidation (RBO) pathway, while co-fermentation of sludge and grass stimulated MCFAs production by strengthening fatty acid biosynthesis (FAB) pathway.
Collapse
Affiliation(s)
- Yanan Yin
- Laboratory of Environmental Technology, INET, Tsinghua University, Beijing 100084, PR China
| | - Yuming Hu
- Laboratory of Environmental Technology, INET, Tsinghua University, Beijing 100084, PR China
| | - Jianlong Wang
- Laboratory of Environmental Technology, INET, Tsinghua University, Beijing 100084, PR China; Beijing Key Laboratory of Radioactive Waste Treatment, INET, Tsinghua University, Beijing 100084, PR China.
| |
Collapse
|
20
|
Seid N, Griesheimer P, Neumann A. Investigating the Processing Potential of Ethiopian Agricultural Residue Enset/Ensete ventricosum for Biobutanol Production. Bioengineering (Basel) 2022; 9:bioengineering9040133. [PMID: 35447693 PMCID: PMC9025969 DOI: 10.3390/bioengineering9040133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Revised: 03/17/2022] [Accepted: 03/21/2022] [Indexed: 12/05/2022] Open
Abstract
The Enset plant is a potential food source for about 20 million Ethiopians. A massive amount of residual byproduct is discarded from traditional Ethiopian Enset food processing. This study shows a compositional analysis of Enset biomass and its use for biobutanol production. The Enset biomass was pretreated with 2% (w/v) NaOH or 2% (v/v) H2SO4 and subjected to enzymatic hydrolysis. The enzymatic hydrolysates were then fermented anaerobically by C. saccharoperbutylacetonicum DSM 14923. The majority of Enset biomass waste samples contained 36–67% cellulose, 16–20% hemicelluloses, and less than 6.8% lignin. In all alkali-pretreated Enset biomass samples, the enzyme converted 80–90% of the biomass to glucose within 24 h, while it took 60 h to convert 48–80% of the acid-pretreated Enset biomass. In addition, the alkali pretreatment method released more glucose than the acid pretreatment in all Enset biomass samples. After 72 h of ABE fermentation, 2.8 g/L acetone, 9.9 g/L butanol, and 1.6 g/L ethanol were produced from mixed Enset waste hydrolysate pretreated with alkali, achieving an ABE yield of 0.32 g/g and productivity of 0.2 g × L−1 × h−1, showing the first value of butanol produced from Enset biomass in the literature.
Collapse
Affiliation(s)
- Nebyat Seid
- Technical Biology, Institute of Process Engineering in Life Science 2, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany;
| | - Pia Griesheimer
- Institute of Catalysis Research and Technology, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany;
| | - Anke Neumann
- Technical Biology, Institute of Process Engineering in Life Science 2, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany;
- Correspondence:
| |
Collapse
|
21
|
Logroño W, Nikolausz M, Harms H, Kleinsteuber S. Physiological Effects of 2-Bromoethanesulfonate on Hydrogenotrophic Pure and Mixed Cultures. Microorganisms 2022; 10:microorganisms10020355. [PMID: 35208809 PMCID: PMC8877471 DOI: 10.3390/microorganisms10020355] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 01/28/2022] [Accepted: 02/01/2022] [Indexed: 01/27/2023] Open
Abstract
Mixed or pure cultures can be used for biomethanation of hydrogen. Sodium 2-bromoethanesulfonate (BES) is an inhibitor of methanogenesis used to investigate competing reactions like homoacetogenesis in mixed cultures. To understand the effect of BES on the hydrogenotrophic metabolism in a biomethanation process, anaerobic granules from a wastewater treatment plant, a hydrogenotrophic enrichment culture, and pure cultures of Methanococcus maripaludis and Methanobacterium formicicum were incubated under H2/CO2 headspace in the presence or absence of BES, and the turnover of H2, CO2, CH4, formate and acetate was analyzed. Anaerobic granules produced the highest amount of formate after 24 h of incubation in the presence of BES. Treating the enrichment culture with BES led to the accumulation of formate. M. maripaludis produced more formate than M. formicicum when treated with BES. The non-inhibited methanogenic communities produced small amounts of formate whereas the pure cultures did not. The highest amount of acetate was produced by the anaerobic granules concomitantly with formate consumption. These results indicate that formate is an important intermediate of hydrogenotrophic metabolism accumulating upon methanogenesis inhibition.
Collapse
|
22
|
Kang S, Kim H, Jeon BS, Choi O, Sang BI. Chain elongation process for caproate production using lactate as electron donor in Megasphaera hexanoica. BIORESOURCE TECHNOLOGY 2022; 346:126660. [PMID: 34974100 DOI: 10.1016/j.biortech.2021.126660] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Revised: 12/24/2021] [Accepted: 12/28/2021] [Indexed: 05/12/2023]
Abstract
Megasphaera hexnaoica is anaerobic bacteria who has well running reverse β-oxidation pathway. In previous study, the strain showed excellent production of medium chain carboxylic acids (MCCAs) using fructose as electron donor. In this study, chain elongation process study using lactate instead of fructose was conducted in M. hexnaoica fermentation. It was found that M. hexanoica can use lactate as electron donor in chain elongation process. 8.9 g/L caproate production was achieved in fermentation using lactate as sole electron donor. Compare to fructose condition, lactate as electron donor showed more than 3 times higher specific titer and specific productivity. In addition, when fructose and lactate were used as electron donor simultaneously, further improvement of MCCAs production was observed to achieve maximum caproate productivity of 20.9 g/L/day. Utilization of lactate as electron donor in M. hexanoica showed potential opportunity in chain elongation process.
Collapse
Affiliation(s)
- Seongcheol Kang
- Department of Chemical Engineering, Hanyang University, 222, Wangsimni-ro, Seongdong-gu, Seoul 04763, Republic of Korea
| | - Hyunjin Kim
- Department of Chemical Engineering, Hanyang University, 222, Wangsimni-ro, Seongdong-gu, Seoul 04763, Republic of Korea
| | - Byoung Seung Jeon
- Korea Institute of Ceramic Engineering and Technology (KICET), 202, Osongsaengmyeong 1-ro, Heungdeck-gu, Cheongju-si, Chungcheongbuk-do 28160, Republic of Korea
| | - Okkyoung Choi
- Department of Chemical Engineering, Hanyang University, 222, Wangsimni-ro, Seongdong-gu, Seoul 04763, Republic of Korea
| | - Byoung-In Sang
- Department of Chemical Engineering, Hanyang University, 222, Wangsimni-ro, Seongdong-gu, Seoul 04763, Republic of Korea.
| |
Collapse
|
23
|
Baleeiro FCF, Ardila MS, Kleinsteuber S, Sträuber H. Effect of Oxygen Contamination on Propionate and Caproate Formation in Anaerobic Fermentation. Front Bioeng Biotechnol 2021; 9:725443. [PMID: 34568301 PMCID: PMC8460912 DOI: 10.3389/fbioe.2021.725443] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 08/19/2021] [Indexed: 01/19/2023] Open
Abstract
Mixed microbial cultures have become a preferred choice of biocatalyst for chain elongation systems due to their ability to convert complex substrates into medium-chain carboxylates. However, the complexity of the effects of process parameters on the microbial metabolic networks is a drawback that makes the task of optimizing product selectivity challenging. Here, we studied the effects of small air contaminations on the microbial community dynamics and the product formation in anaerobic bioreactors fed with lactate, acetate and H2/CO2. Two stirred tank reactors and two bubble column reactors were operated with H2/CO2 gas recirculation for 139 and 116 days, respectively, at pH 6.0 and 32°C with a hydraulic retention time of 14 days. One reactor of each type had periods with air contamination (between 97 ± 28 and 474 ± 33 mL O2 L−1 d−1, lasting from 4 to 32 days), while the control reactors were kept anoxic. During air contamination, production of n-caproate and CH4 was strongly inhibited, whereas no clear effect on n-butyrate production was observed. In a period with detectable O2 concentrations that went up to 18%, facultative anaerobes of the genus Rummeliibacillus became predominant and only n-butyrate was produced. However, at low air contamination rates and with O2 below the detection level, Coriobacteriia and Actinobacteria gained a competitive advantage over Clostridia and Methanobacteria, and propionate production rates increased to 0.8–1.8 mmol L−1 d−1 depending on the reactor (control reactors 0.1–0.8 mmol L−1 d−1). Moreover, i-butyrate production was observed, but only when Methanobacteria abundances were low and, consequently, H2 availability was high. After air contamination stopped completely, production of n-caproate and CH4 recovered, with n-caproate production rates of 1.4–1.8 mmol L−1 d−1 (control 0.7–2.1 mmol L−1 d−1). The results underline the importance of keeping strictly anaerobic conditions in fermenters when consistent n-caproate production is the goal. Beyond that, micro-aeration should be further tested as a controllable process parameter to shape the reactor microbiome. When odd-chain carboxylates are desired, further studies can develop strategies for their targeted production by applying micro-aerobic conditions.
Collapse
Affiliation(s)
- Flávio C F Baleeiro
- Department of Environmental Microbiology, Helmholtz Centre for Environmental Research - UFZ, Leipzig, Germany.,Institute of Process Engineering in Life Science 2, Technical Biology, Karlsruhe Institute of Technology - KIT, Karlsruhe, Germany
| | - Magda S Ardila
- Department of Environmental Microbiology, Helmholtz Centre for Environmental Research - UFZ, Leipzig, Germany.,Institute of Process Engineering in Life Science 2, Technical Biology, Karlsruhe Institute of Technology - KIT, Karlsruhe, Germany
| | - Sabine Kleinsteuber
- Department of Environmental Microbiology, Helmholtz Centre for Environmental Research - UFZ, Leipzig, Germany
| | - Heike Sträuber
- Department of Environmental Microbiology, Helmholtz Centre for Environmental Research - UFZ, Leipzig, Germany
| |
Collapse
|