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Nwanebu E, Jezernik M, Lawson C, Bruant G, Tartakovsky B. Impact of cathodic pH and bioaugmentation on acetate and CH 4 production in a microbial electrosynthesis cell. RSC Adv 2024; 14:22962-22973. [PMID: 39086992 PMCID: PMC11290334 DOI: 10.1039/d4ra03906h] [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: 05/27/2024] [Accepted: 06/20/2024] [Indexed: 08/02/2024] Open
Abstract
This study compares carbon dioxide conversion in carbonate-fed microbial electrosynthesis (MES) cells operated at low (5.3), neutral (7) and high (8) pH levels and inoculated either with wild-type or bioaugmented mixed microbial populations. Two 100 mL (cathode volume) MES cells inoculated with anaerobic digester sludge were operated with a continuous supply of carbonate solution (5 g L-1 as CO3 2-). Acetate production was highest at low pH, however CH4 production still persisted, possibly due to pH gradients within the cathodic biofilm, resulting in acetate and CH4 volumetric (per cathode compartment volume) production rates of 1.0 ± 0.1 g (Lc d)-1 and 0.84 ± 0.05 L (Lc d)-1, respectively. To enhance production of carboxylic acids, four strains of acetogenic bacteria (Clostridium carboxidivorans, Clostridium ljungdahlii, Clostridium autoethanogenum, and Eubacterium limosum) were added to both MES cells. In the bioaugmented MES cells, acetate production increased to 2.0 g (Lc d)-1. However, production of other carboxylic acids such as butyrate and caproate was insignificant. Furthermore, 16S rRNA gene sequencing of cathodic biofilm and suspended biomass suggested a low density of introduced acetogenic bacteria implying that selective pressure rather than bioaugmentation led to improved acetate production.
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Affiliation(s)
- Emmanuel Nwanebu
- Energy, Mining and Environment Research Centre, National Research Council Canada 6100 Royalmount Avenue Montreal Quebec H4P 2R2 Canada
| | - Mara Jezernik
- Department of Chemical Engineering & Applied Chemistry, University of Toronto Toronto Canada
| | - Christopher Lawson
- Department of Chemical Engineering & Applied Chemistry, University of Toronto Toronto Canada
| | - Guillaume Bruant
- Energy, Mining and Environment Research Centre, National Research Council Canada 6100 Royalmount Avenue Montreal Quebec H4P 2R2 Canada
| | - Boris Tartakovsky
- Energy, Mining and Environment Research Centre, National Research Council Canada 6100 Royalmount Avenue Montreal Quebec H4P 2R2 Canada
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2
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Romans-Casas M, Feliu-Paradeda L, Tedesco M, Hamelers HV, Bañeras L, Balaguer MD, Puig S, Dessì P. Selective butyric acid production from CO 2 and its upgrade to butanol in microbial electrosynthesis cells. ENVIRONMENTAL SCIENCE AND ECOTECHNOLOGY 2024; 17:100303. [PMID: 37635954 PMCID: PMC10457423 DOI: 10.1016/j.ese.2023.100303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 07/16/2023] [Accepted: 07/22/2023] [Indexed: 08/29/2023]
Abstract
Microbial electrosynthesis (MES) is a promising carbon utilization technology, but the low-value products (i.e., acetate or methane) and the high electric power demand hinder its industrial adoption. In this study, electrically efficient MES cells with a low ohmic resistance of 15.7 mΩ m2 were operated galvanostatically in fed-batch mode, alternating periods of high CO2 and H2 availability. This promoted acetic acid and ethanol production, ultimately triggering selective (78% on a carbon basis) butyric acid production via chain elongation. An average production rate of 14.5 g m-2 d-1 was obtained at an applied current of 1.0 or 1.5 mA cm-2, being Megasphaera sp. the key chain elongating player. Inoculating a second cell with the catholyte containing the enriched community resulted in butyric acid production at the same rate as the previous cell, but the lag phase was reduced by 82%. Furthermore, interrupting the CO2 feeding and setting a constant pH2 of 1.7-1.8 atm in the cathode compartment triggered solventogenic butanol production at a pH below 4.8. The efficient cell design resulted in average cell voltages of 2.6-2.8 V and a remarkably low electric energy requirement of 34.6 kWhel kg-1 of butyric acid produced, despite coulombic efficiencies being restricted to 45% due to the cross-over of O2 and H2 through the membrane. In conclusion, this study revealed the optimal operating conditions to achieve energy-efficient butyric acid production from CO2 and suggested a strategy to further upgrade it to valuable butanol.
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Affiliation(s)
- Meritxell Romans-Casas
- LEQUiA, Institute of the Environment, University of Girona. Campus Montilivi, Carrer Maria Aurèlia Capmany 69, E-17003, Girona, Spain
| | - Laura Feliu-Paradeda
- Molecular Microbial Ecology Group, Institute of Aquatic Ecology, University of Girona, Maria Aurèlia Capmany 40, 17003, Girona, Spain
| | - Michele Tedesco
- Wetsus, European Centre of Excellence for Sustainable Water Technology, Oostergoweg 9, 8911, MA, Leeuwarden, the Netherlands
| | - Hubertus V.M. Hamelers
- Wetsus, European Centre of Excellence for Sustainable Water Technology, Oostergoweg 9, 8911, MA, Leeuwarden, the Netherlands
| | - Lluis Bañeras
- Molecular Microbial Ecology Group, Institute of Aquatic Ecology, University of Girona, Maria Aurèlia Capmany 40, 17003, Girona, Spain
| | - M. Dolors Balaguer
- LEQUiA, Institute of the Environment, University of Girona. Campus Montilivi, Carrer Maria Aurèlia Capmany 69, E-17003, Girona, Spain
| | - Sebastià Puig
- LEQUiA, Institute of the Environment, University of Girona. Campus Montilivi, Carrer Maria Aurèlia Capmany 69, E-17003, Girona, Spain
| | - Paolo Dessì
- LEQUiA, Institute of the Environment, University of Girona. Campus Montilivi, Carrer Maria Aurèlia Capmany 69, E-17003, Girona, Spain
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Kimura ZI, Kuriyama H, Iwasaki Y. Exploring Acetogenesis in Firmicutes: From Phylogenetic Analysis to Solid Medium Cultivation with Solid-Phase Electrochemical Isolation Equipments. Microorganisms 2023; 11:2976. [PMID: 38138120 PMCID: PMC10746088 DOI: 10.3390/microorganisms11122976] [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: 09/05/2023] [Revised: 11/24/2023] [Accepted: 12/06/2023] [Indexed: 12/24/2023] Open
Abstract
This study introduces a groundbreaking approach for the exploration and utilization of electrotrophic acetogens, essential for advancing microbial electrosynthesis systems (MES). Our initial focus was the development of Solid-Phase Electrochemical Isolation Equipment (SPECIEs), a novel cultivation method for isolating electrotrophic acetogens directly from environmental samples on a solid medium. SPECIEs uses electrotrophy as a selection pressure, successfully overcoming the traditional cultivation method limitations and enabling the cultivation of diverse microbial communities with enhanced specificity towards acetogens. Following the establishment of SPECIEs, we conducted a genome-based phylogenetic analysis using the Genome Taxonomy Database (GTDB) to identify potential electrotrophic acetogens within the Firmicutes phylum and its related lineages. Subsequently, we validated the electrotrophic capabilities of selected strains under electrode-oxidizing conditions in a liquid medium. This sequential approach, integrating innovative cultivation techniques with detailed phylogenetic analysis, paves the way for further advances in microbial cultivation and the identification of new biocatalysts for sustainable energy applications.
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Affiliation(s)
- Zen-ichiro Kimura
- Department of Civil and Environmental Engineering, National Institute of Technology, Kure College, 2-2-11 Aga-minami, Kure, Hiroshima 737-8506, Japan; (H.K.); (Y.I.)
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Chen W, Zeng Y, Liu H, Sun D, Liu X, Xu H, Wu H, Qiu B, Dang Y. Granular activated carbon enhances volatile fatty acid production in the anaerobic fermentation of garden wastes. Front Bioeng Biotechnol 2023; 11:1330293. [PMID: 38146344 PMCID: PMC10749581 DOI: 10.3389/fbioe.2023.1330293] [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: 10/30/2023] [Accepted: 11/20/2023] [Indexed: 12/27/2023] Open
Abstract
Garden waste, one type of lignocellulosic biomass, holds significant potential for the production of volatile fatty acids (VFAs) through anaerobic fermentation. However, the hydrolysis efficiency of garden waste is limited by the inherent recalcitrance, which further influences VFA production. Granular activated carbon (GAC) could promote hydrolysis and acidogenesis efficiency during anaerobic fermentation. This study developed a strategy to use GAC to enhance the anaerobic fermentation of garden waste without any complex pretreatments and extra enzymes. The results showed that GAC addition could improve VFA production, especially acetate, and reach the maximum total VFA yield of 191.55 mg/g VSadded, which increased by 27.35% compared to the control group. The highest VFA/sCOD value of 70.01% was attained in the GAC-amended group, whereas the control group only reached 49.35%, indicating a better hydrolysis and acidogenesis capacity attributed to the addition of GAC. Microbial community results revealed that GAC addition promoted the enrichment of Caproiciproducens and Clostridium, which are crucial for anaerobic VFA production. In addition, only the GAC-amended group showed the presence of Sphaerochaeta and Oscillibacter genera, which are associated with electron transfer processes. Metagenomics analysis indicated that GAC addition improved the abundance of glycoside hydrolases (GHs) and key functional enzymes related to hydrolysis and acidogenesis. Furthermore, the assessment of major genera influencing functional genes in both groups indicated that Sphaerochaeta, Clostridium, and Caproicibacter were the primary contributors to upregulated genes. These findings underscored the significance of employing GAC to enhance the anaerobic fermentation of garden waste, offering a promising approach for sustainable biomass conversion and VFA production.
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Affiliation(s)
- Wenwen Chen
- Beijing Key Laboratory for Source Control Technology of Water Pollution, Engineering Research Center for Water Pollution Source Control and Eco-Remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, China
| | - Yiwei Zeng
- Beijing Key Laboratory for Source Control Technology of Water Pollution, Engineering Research Center for Water Pollution Source Control and Eco-Remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, China
| | - Huanying Liu
- Beijing Key Laboratory for Source Control Technology of Water Pollution, Engineering Research Center for Water Pollution Source Control and Eco-Remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, China
| | - Dezhi Sun
- Beijing Key Laboratory for Source Control Technology of Water Pollution, Engineering Research Center for Water Pollution Source Control and Eco-Remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, China
| | - Xinying Liu
- Beijing Key Laboratory for Source Control Technology of Water Pollution, Engineering Research Center for Water Pollution Source Control and Eco-Remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, China
| | - Haiyu Xu
- Qinglin Chuangneng (Shanghai) Technology Co., Ltd., Shanghai, China
| | - Hongbin Wu
- Qinglin Chuangneng (Shanghai) Technology Co., Ltd., Shanghai, China
| | - Bin Qiu
- Beijing Key Laboratory for Source Control Technology of Water Pollution, Engineering Research Center for Water Pollution Source Control and Eco-Remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, China
| | - Yan Dang
- Beijing Key Laboratory for Source Control Technology of Water Pollution, Engineering Research Center for Water Pollution Source Control and Eco-Remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, China
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Dessì P, Buenaño-Vargas C, Martínez-Sosa S, Mills S, Trego A, Ijaz UZ, Pant D, Puig S, O'Flaherty V, Farràs P. Microbial electrosynthesis of acetate from CO 2 in three-chamber cells with gas diffusion biocathode under moderate saline conditions. ENVIRONMENTAL SCIENCE AND ECOTECHNOLOGY 2023; 16:100261. [PMID: 37089695 PMCID: PMC10120373 DOI: 10.1016/j.ese.2023.100261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 02/23/2023] [Accepted: 03/10/2023] [Indexed: 05/03/2023]
Abstract
The industrial adoption of microbial electrosynthesis (MES) is hindered by high overpotentials deriving from low electrolyte conductivity and inefficient cell designs. In this study, a mixed microbial consortium originating from an anaerobic digester operated under saline conditions (∼13 g L-1 NaCl) was adapted for acetate production from bicarbonate in galvanostatic (0.25 mA cm-2) H-type cells at 5, 10, 15, or 20 g L-1 NaCl concentration. The acetogenic communities were successfully enriched only at 5 and 10 g L-1 NaCl, revealing an inhibitory threshold of about 6 g L-1 Na+. The enriched planktonic communities were then used as inoculum for 3D printed, three-chamber cells equipped with a gas diffusion biocathode. The cells were fed with CO2 gas and operated galvanostatically (0.25 or 1.00 mA cm-2). The highest production rate of 55.4 g m-2 d-1 (0.89 g L-1 d-1), with 82.4% Coulombic efficiency, was obtained at 5 g L-1 NaCl concentration and 1 mA cm-2 applied current, achieving an average acetate production of 44.7 kg MWh-1. Scanning electron microscopy and 16S rRNA sequencing analysis confirmed the formation of a cathodic biofilm dominated by Acetobacterium sp. Finally, three 3D printed cells were hydraulically connected in series to simulate an MES stack, achieving three-fold production rates than with the single cell at 0.25 mA cm-2. This confirms that three-chamber MES cells are an efficient and scalable technology for CO2 bio-electro recycling to acetate and that moderate saline conditions (5 g L-1 NaCl) can help reduce their power demand while preserving the activity of acetogens.
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Affiliation(s)
- Paolo Dessì
- School of Biological and Chemical Sciences and Energy Research Centre, Ryan Institute, University of Galway, University Road, H91 CF50, Galway, Ireland
- LEQUiA, Institute of the Environment, University of Girona, Carrer Maria Aurèlia Capmany 69, E-17003, Girona, Spain
- Corresponding author. LEQUiA, Institute of the Environment, University of Girona, Carrer Maria Aurèlia Capmany 69, E-17003, Girona, Spain.
| | - Claribel Buenaño-Vargas
- Microbiology Department, School of Natural Sciences, University of Galway, University Road, H91 TK33, Galway, Ireland
| | - Santiago Martínez-Sosa
- School of Biological and Chemical Sciences and Energy Research Centre, Ryan Institute, University of Galway, University Road, H91 CF50, Galway, Ireland
| | - Simon Mills
- Microbiology Department, School of Natural Sciences, University of Galway, University Road, H91 TK33, Galway, Ireland
| | - Anna Trego
- Microbiology Department, School of Natural Sciences, University of Galway, University Road, H91 TK33, Galway, Ireland
| | - Umer Z. Ijaz
- Infrastructure and Environment Research Division, School of Engineering, University of Glasgow, Glasgow, United Kingdom
| | - Deepak Pant
- Separation and Conversion Technology, Flemish Institute for Technological Research (VITO), Boeretang 200, 2400, Mol, Belgium
| | - Sebastià Puig
- LEQUiA, Institute of the Environment, University of Girona, Carrer Maria Aurèlia Capmany 69, E-17003, Girona, Spain
| | - Vincent O'Flaherty
- Microbiology Department, School of Natural Sciences, University of Galway, University Road, H91 TK33, Galway, Ireland
| | - Pau Farràs
- School of Biological and Chemical Sciences and Energy Research Centre, Ryan Institute, University of Galway, University Road, H91 CF50, Galway, Ireland
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Romans-Casas M, Perona-Vico E, Dessì P, Bañeras L, Balaguer MD, Puig S. Boosting ethanol production rates from carbon dioxide in MES cells under optimal solventogenic conditions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 856:159124. [PMID: 36179842 DOI: 10.1016/j.scitotenv.2022.159124] [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: 07/18/2022] [Revised: 09/01/2022] [Accepted: 09/25/2022] [Indexed: 06/16/2023]
Abstract
Microbial Electrosynthesis (MES) has been widely applied for acetic acid (HA) production from CO2 and electricity. Ethanol (EtOH) has a higher market value than HA, and wide application in industry and as a biofuel. However, it has only been obtained sporadically and at low concentrations, probably due to sub-optimal operating conditions. This study aimed at enhancing EtOH productivity in MES cells by jointly optimising key operation parameters, including pH, H2 and CO2 partial pressure (pH2 and pCO2), and HA concentration, to promote solventogenesis. Two H-type cells were operated in fed-batch mode at -0.8 V vs. SHE with CO2 as the sole carbon source. A mixed culture, enriched with Clostridium ljungdahlii was used as the biocatalyst. The combination of low pH (<4.5) and pCO2 (<0.3 atm), along with high HA concentration (about 6 g L-1) and pH2 (>3 atm), were mandatory conditions for maintaining an efficient solventogenic culture, dominated by Clostridium sp., capable of high-rate EtOH production. The maximum EtOH production rate was 10.95 g m-2 d-1, and a concentration of 5.28 g L-1 was achieved. Up to 30 % of the electrons and 15.2 % of the carbon provided were directed towards EtOH production, and 28.1 kWh were required for the synthesis of 1 kg of EtOH from CO2. These results highlight that strict conditions are required for a continuous, reliable, EtOH production in MES cells. Future investigation should focus on improving cell configuration to achieve EtOH production at higher current densities while minimizing the electric energy input.
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Affiliation(s)
- M Romans-Casas
- LEQUiA, Institute of the Environment, University of Girona, Campus Montilivi, C/Maria Aurèlia Capmany, 69, E-17003 Girona, Spain
| | - E Perona-Vico
- gEMM. Group of Molecular Microbial Ecology, Institute of Aquatic Ecology, University of Girona, Campus Montilivi, C/Maria Aurèlia Capmany, 40, E-17003 Girona, Spain
| | - P Dessì
- LEQUiA, Institute of the Environment, University of Girona, Campus Montilivi, C/Maria Aurèlia Capmany, 69, E-17003 Girona, Spain
| | - L Bañeras
- gEMM. Group of Molecular Microbial Ecology, Institute of Aquatic Ecology, University of Girona, Campus Montilivi, C/Maria Aurèlia Capmany, 40, E-17003 Girona, Spain
| | - M D Balaguer
- LEQUiA, Institute of the Environment, University of Girona, Campus Montilivi, C/Maria Aurèlia Capmany, 69, E-17003 Girona, Spain
| | - S Puig
- LEQUiA, Institute of the Environment, University of Girona, Campus Montilivi, C/Maria Aurèlia Capmany, 69, E-17003 Girona, Spain.
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Bakonyi P, Koók L, Rózsenberszki T, Kalauz-Simon V, Bélafi-Bakó K, Nemestóthy N. CO2-refinery through microbial electrosynthesis (MES): A concise review on design, operation, biocatalysts and perspectives. J CO2 UTIL 2023. [DOI: 10.1016/j.jcou.2022.102348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
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8
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A meta-analysis of acetogenic and methanogenic microbiomes in microbial electrosynthesis. NPJ Biofilms Microbiomes 2022; 8:73. [PMID: 36138044 PMCID: PMC9500080 DOI: 10.1038/s41522-022-00337-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Accepted: 09/09/2022] [Indexed: 11/24/2022] Open
Abstract
A meta-analysis approach was used, to study the microbiomes of biofilms and planktonic communities underpinning microbial electrosynthesis (MES) cells. High-throughput DNA sequencing of 16S rRNA gene amplicons has been increasingly applied to understand MES systems. In this meta-analysis of 22 studies, we find that acetogenic and methanogenic MES cells share 80% of a cathodic core microbiome, and that different inoculum pre-treatments strongly affect community composition. Oxygen scavengers were more abundant in planktonic communities, and several key organisms were associated with operating parameters and good cell performance. We suggest Desulfovibrio sp. play a role in initiating early biofilm development and shaping microbial communities by catalysing H2 production, to sustain either Acetobacterium sp. or Methanobacterium sp. Microbial community assembly became more stochastic over time, causing diversification of the biofilm (cathodic) community in acetogenic cells and leading to re-establishment of methanogens, despite inoculum pre-treatments. This suggests that repeated interventions may be required to suppress methanogenesis.
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Lu Y, Xiang M, Xin L, Zhang Y, Wang Y, Shen Z, Li L, Cui X. Qiliqiangxin Modulates the Gut Microbiota and NLRP3 Inflammasome to Protect Against Ventricular Remodeling in Heart Failure. Front Pharmacol 2022; 13:905424. [PMID: 35721118 PMCID: PMC9201726 DOI: 10.3389/fphar.2022.905424] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2022] [Accepted: 04/13/2022] [Indexed: 02/03/2023] Open
Abstract
Aims: Pathological left ventricular (LV) remodeling induced by multiple causes often triggers fatal cardiac dysfunction, heart failure (HF), and even cardiac death. This study is aimed to investigate whether qiliqiangxin (QL) could improve LV remodeling and protect against HF via modulating gut microbiota and inhibiting nod-like receptor pyrin domain 3 (NLRP3) inflammasome activation. Methods: Rats were respectively treated with QL (100 mg/kg/day) or valsartan (1.6 mg/kg/day) by oral gavage after transverse aortic constriction or sham surgery for 13 weeks. Cardiac functions and myocardial fibrosis were assessed. In addition, gut microbial composition was assessed by 16S rDNA sequencing. Furthermore, rats’ hearts were harvested for histopathological and molecular analyses including immunohistochemistry, immunofluorescence, terminal-deoxynucleotidyl transferase-mediated 2’-deoxyuridine 5’-triphosphated nick end labeling, and Western blot. Key findings: QL treatment preserved cardiac functions including LV ejection fractions and fractional shortening and markedly improved the LV remodeling. Moreover, HF was related to the gut microbial community reorganization like a reduction in Lactobacillus, while QL reversed it. Additionally, the protein expression levels like IL-1β, TNF-α, NF-κB, and NLRP3 were decreased in the QL treatment group compared to the model one. Conclusion: QL ameliorates ventricular remodeling to some extent in rats with HF by modulating the gut microbiota and NLRP3 inflammasome, which indicates the potential therapeutic effects of QL on those who suffer from HF.
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Affiliation(s)
- Yingdong Lu
- Department of Cardiovascular, Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Mi Xiang
- Department of Cardiovascular, Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Laiyun Xin
- Department of Cardiovascular, Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China.,First Clinical Medical School, Shandong University of Chinese Medicine, Jinan, China
| | - Yang Zhang
- Department of Cardiovascular, Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China.,First Clinical Medical School, Shandong University of Chinese Medicine, Jinan, China
| | - Yuling Wang
- Department of Cardiovascular, Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Zihuan Shen
- Department of Cardiovascular, Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Li Li
- Department of Cardiovascular, Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Xiangning Cui
- Department of Cardiovascular, Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
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Wu Q, Ren W, Guo W, Ren N. Effect of substrate structure on medium chain fatty acids production and reactor microbiome. ENVIRONMENTAL RESEARCH 2022; 204:111947. [PMID: 34454935 DOI: 10.1016/j.envres.2021.111947] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Revised: 07/23/2021] [Accepted: 08/20/2021] [Indexed: 06/13/2023]
Abstract
The medium chain fatty acids (MCFAs) produced from organic wastes can replace part fossil-fuel-based products to promote the sustainable development of economy and environment. However, the selection and collocation of feedstocks for MCFAs production are lack of reference basis. This study thereby aimed to investigate how the commonly used electron donor (ED) and substrate configuration affect MCFAs synthesis and then obtain the optimal substrate composition. It was found that the optimized ratios for ethanol/acetate, lactate/acetate, and ethanol/lactate/acetate were 3/1, 2/1, and 2/1/1, respectively, and the optimal substrate concentration was 400 mM C. Combining ethanol and lactate as co-EDs effectively concentrated substrate-carbon-flow (increased by 20-28% than sole ED) on MCFAs synthesis by promoting the elongation of butyrate and reutilization of by-products. As a result, the higher MCFAs yield of 646.22 mg COD/g COD and selectivity of 67.72% were obtained from co-EDs than those from sole ED. Moreover, the key functional bacteria enriched under different ED were also discrepant, which were Clostridium sensu stricto for ethanol, Corynebacterium for lactate, and Veillonella and Oscillibacter for ethanol-lactate, respectively. This study provided a basic but significant reference for the scale-up MCFAs production.
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Affiliation(s)
- Qinglian Wu
- College of Architecture and Environment, Sichuan University, Chengdu, 610065, China
| | - Weitong Ren
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Wanqian Guo
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090, China.
| | - Nanqi Ren
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090, China
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11
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Vassilev I, Dessì P, Puig S, Kokko M. Cathodic biofilms - A prerequisite for microbial electrosynthesis. BIORESOURCE TECHNOLOGY 2022; 348:126788. [PMID: 35104648 DOI: 10.1016/j.biortech.2022.126788] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Revised: 01/24/2022] [Accepted: 01/25/2022] [Indexed: 05/20/2023]
Abstract
Cathodic biofilms have an important role in CO2 bio-reduction to carboxylic acids and biofuels in microbial electrosynthesis (MES) cells. However, robust and resilient electroactive biofilms for an efficient CO2 conversion are difficult to achieve. In this review, the fundamentals of cathodic biofilm formation, including energy conservation, electron transfer and development of catalytic biofilms, are presented. In addition, strategies for improving cathodic biofilm formation, such as the selection of electrode and carrier materials, cell design and operational conditions, are described. The knowledge gaps are individuated, and possible solutions are proposed to achieve stable and productive biofilms in MES cathodes.
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Affiliation(s)
- Igor Vassilev
- Faculty of Engineering and Natural Sciences, Tampere University, Korkeakoulunkatu 8, 33720, Tampere, Finland
| | - Paolo Dessì
- School of Chemistry and Energy Research Centre, Ryan Institute, National University of Ireland Galway, University Road, H91 TK33 Galway, Ireland
| | - Sebastià Puig
- LEQUIA. Institute of Environment. University of Girona, Carrer Maria Aurèlia Capmany 69, 17003, Girona, Spain
| | - Marika Kokko
- Faculty of Engineering and Natural Sciences, Tampere University, Korkeakoulunkatu 8, 33720, Tampere, Finland.
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12
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He Y, Lens PNL, Veiga MC, Kennes C. Selective butanol production from carbon monoxide by an enriched anaerobic culture. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 806:150579. [PMID: 34582872 DOI: 10.1016/j.scitotenv.2021.150579] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 09/21/2021] [Accepted: 09/21/2021] [Indexed: 06/13/2023]
Abstract
An anaerobic mixed culture able to grow on pure carbon monoxide (CO) as well as syngas (CO, CO2 and H2), that produced unusual high concentrations of butanol, was enriched in a bioreactor with intermittent CO gas feeding. At pH 6.2, it mainly produced acids, generally acetic and butyric acid. After adaptation, under stress conditions of CO exposure at a partial pressure of 1.8 bar and low pH (e.g., 5.7), the enrichment accumulated ethanol, but also high amounts of butanol, up to 6.8 g/L, never reported before, with a high butanol/butyric acid molar ratio of 12.6, highlighting the high level of acid to alcohol conversion. At the end of the assay, both the acetic acid and ethanol concentrations decreased, with concomitant butyric acid production, suggesting C2 to C4 acid bioconversion, though this was not a dominant bioconversion process. The reverse reaction of ethanol oxidation to acetic acid was observed in the presence of CO2 produced during CO fermentation. Interestingly, butanol oxidation with simultaneous butyric acid production occurred upon production of CO2 from CO, which has to the best of our knowledge never been reported. Although the sludge inoculum contained a few known solventogenic Clostridia, the relative taxonomic abundance of the enriched sludge was diverse in Clostridia and Bacilli classes, containing known solventogens, e.g., Clostridium ljungdhalii, Clostridium ragsdalei and Clostridium coskatii, confirming their efficient enrichment. The relative abundance of unassigned Clostridium species amounted to 27% with presumably novel ethanol/butanol producers.
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Affiliation(s)
- Yaxue He
- Chemical Engineering Laboratory, Faculty of Sciences and Center for Advanced Scientific Research (CICA), BIOENGIN Group, University of La Coruña (UDC), E-15008 La Coruña, Spain; National University of Ireland Galway, H91 TK33 Galway, Ireland
| | - Piet N L Lens
- National University of Ireland Galway, H91 TK33 Galway, Ireland
| | - María C Veiga
- Chemical Engineering Laboratory, Faculty of Sciences and Center for Advanced Scientific Research (CICA), BIOENGIN Group, University of La Coruña (UDC), E-15008 La Coruña, Spain
| | - Christian Kennes
- Chemical Engineering Laboratory, Faculty of Sciences and Center for Advanced Scientific Research (CICA), BIOENGIN Group, University of La Coruña (UDC), E-15008 La Coruña, Spain.
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13
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Alvarez Chavez B, Raghavan V, Tartakovsky B. A comparative analysis of biopolymer production by microbial and bioelectrochemical technologies. RSC Adv 2022; 12:16105-16118. [PMID: 35733669 PMCID: PMC9159792 DOI: 10.1039/d1ra08796g] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Accepted: 05/03/2022] [Indexed: 12/02/2022] Open
Abstract
Production of biopolymers from renewable carbon sources provides a path towards a circular economy. This review compares several existing and emerging approaches for polyhydroxyalkanoate (PHA) production from soluble organic and gaseous carbon sources and considers technologies based on pure and mixed microbial cultures. While bioplastics are most often produced from soluble sources of organic carbon, the use of carbon dioxide (CO2) as the carbon source for PHA production is emerging as a sustainable approach that combines CO2 sequestration with the production of a value-added product. Techno-economic analysis suggests that the emerging approach of CO2 conversion to carboxylic acids by microbial electrosynthesis followed by microbial PHA production could lead to a novel cost-efficient technology for production of green biopolymers. Biopolymers production from renewable carbon sources.![]()
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Affiliation(s)
- Brenda Alvarez Chavez
- McGill University, Bioresource Engineering Department, 21111 Lakeshore Rd., Ste-Anne-de-Bellevue, QC H9X 3V9, Canada
- National Research Council of Canada, 6100 Royalmount Ave, Montreal, QC H4P 2R2, Canada
| | - Vijaya Raghavan
- McGill University, Bioresource Engineering Department, 21111 Lakeshore Rd., Ste-Anne-de-Bellevue, QC H9X 3V9, Canada
| | - Boris Tartakovsky
- McGill University, Bioresource Engineering Department, 21111 Lakeshore Rd., Ste-Anne-de-Bellevue, QC H9X 3V9, Canada
- National Research Council of Canada, 6100 Royalmount Ave, Montreal, QC H4P 2R2, Canada
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14
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Cheng S, Liu Z, Varrone C, Zhou A, He Z, Li H, Zhang J, Liu W, Yue X. Elucidating the microbial ecological mechanisms on the electro-fermentation of caproate production from acetate via ethanol-driven chain elongation. ENVIRONMENTAL RESEARCH 2022; 203:111875. [PMID: 34403665 DOI: 10.1016/j.envres.2021.111875] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 08/04/2021] [Accepted: 08/09/2021] [Indexed: 06/13/2023]
Abstract
Electro-fermentation (EF) is an attractive way to implement the chain elongation (CE) process, by controlling the fermentation environment and reducing the dosage of external electron donors (EDs). However, besides the coexistence performance of external EDs and electrode, applications of EF technology on the fermentation broth containing both EDs and electron acceptors during CE process, are all still limited. The current study investigated the contribution of EF to caproate production, under different acetate: ethanol ratios (RA/E). The effect of multiple EDs, both from ethanol and the bio-cathode, on caproate production, was also assessed. A proof-of-concept, based on experimental data, was presented for the EF-mediated ethanol-driven CE process. Experimental results showed that ethanol, together with the additional electron donors from the bio-cathode, was beneficial for the stable caproate production. The caproate concentration increased with the decrease of RA/E, while the bio-cathode further contributed to 10.7%-26.1 % increase of caproate concentration. Meanwhile, the hydrogen partial pressure tended to 0.10 ± 0.01 bar in all controlled EF reactors, thus favoring caproate production. This was attributed to the increased availability EDs, i.e., hydrogen and ethanol, generated by the electrode and electrochemically active bacteria (EAB), which might create multiple additional pathways to achieve caproate production. Molecular ecological networks analysis of the key microbiomes further revealed underlying cooperative relationships, beneficial to the chain elongation process. The genus Clostridium_sensu_stricto, as the dominant microbial community, was positively related to acetogens, EAB and fermenters.
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Affiliation(s)
- Shuanglan Cheng
- College of Environmental Science and Engineering, Taiyuan University of Technology, Taiyuan, China
| | - Zhihong Liu
- College of Environmental Science and Engineering, Taiyuan University of Technology, Taiyuan, China.
| | - Cristiano Varrone
- Department of Chemistry and BioScience, Aalborg University, Copenhagen, Denmark
| | - Aijuan Zhou
- College of Environmental Science and Engineering, Taiyuan University of Technology, Taiyuan, China.
| | - Zhangwei He
- Key Laboratory of Northwest Water Resource, Environment and Ecology, Ministry of Education, Xi'an University of Architecture and Technology, Xi'an, 710055, China; Shaanxi Key Laboratory of Environmental Engineering, School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China
| | - Houfen Li
- College of Environmental Science and Engineering, Taiyuan University of Technology, Taiyuan, China
| | - Jiaguang Zhang
- College of Civil Engineering, Taiyuan University of Technology, Taiyuan, China
| | - Wenzong Liu
- School of Civil and Environmental Engineering, Harbin Institute of Technology Shenzhen, Shenzhen, 51805, China
| | - Xiuping Yue
- College of Environmental Science and Engineering, Taiyuan University of Technology, Taiyuan, China
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15
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Yang HY, Hou NN, Wang YX, Liu J, He CS, Wang YR, Li WH, Mu Y. Mixed-culture biocathodes for acetate production from CO 2 reduction in the microbial electrosynthesis: Impact of temperature. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 790:148128. [PMID: 34098277 DOI: 10.1016/j.scitotenv.2021.148128] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 05/26/2021] [Accepted: 05/26/2021] [Indexed: 06/12/2023]
Abstract
The temperature effect on bioelectrochemical reduction of CO2 to acetate with a mixed-culture biocathode in the microbial electrosynthesis was explored. The results showed that maximum acetate amount of 525.84 ± 1.55 mg L-1 and fastest acetate formation of 49.21 ± 0.49 mg L-1 d-1 were obtained under mesophilic conditions. Electron recovery efficiency for CO2 reduction to acetate ranged from 14.50 ± 2.20% to 64.86 ± 2.20%, due to propionate, butyrate and H2 generation. Mesophilic conditions were demonstrated to be more favorable for biofilm formation on the cathode, resulting in a stable and dense biofilm. At phylum level, the relative abundance of Bacteroidetes phylum in the biofilm remarkably increased under mesophilic conditions, compared with that at psychrophilic and thermophilic conditions. At genus level, the Clostridium, Treponema, Acidithiobacillus, Acetobacterium and Acetoanaerobium were found to be dominated genera in the biofilm under mesophilic conditions, while genera diversity decreased under psychrophilic and thermophilic conditions.
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Affiliation(s)
- Hou-Yun Yang
- CAS Key Laboratory for Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science & Technology of China, Hefei, China; Key Laboratory of Water Pollution Control and Wastewater Reuse of Anhui Province, Anhui Provincial Key Laboratory of Environmental Pollution Control and Resource Reuse, Anhui Jianzhu University, Hefei, China
| | - Nan-Nan Hou
- CAS Key Laboratory for Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science & Technology of China, Hefei, China; School of Physics and Materials Engineering, Hefei Normal University, Hefei, China
| | - Yi-Xuan Wang
- CAS Key Laboratory for Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science & Technology of China, Hefei, China.
| | - Jing Liu
- CAS Key Laboratory for Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science & Technology of China, Hefei, China
| | - Chuan-Shu He
- CAS Key Laboratory for Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science & Technology of China, Hefei, China
| | - Yi-Ran Wang
- CAS Key Laboratory for Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science & Technology of China, Hefei, China
| | - Wei-Hua Li
- Key Laboratory of Water Pollution Control and Wastewater Reuse of Anhui Province, Anhui Provincial Key Laboratory of Environmental Pollution Control and Resource Reuse, Anhui Jianzhu University, Hefei, China
| | - Yang Mu
- CAS Key Laboratory for Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science & Technology of China, Hefei, China
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16
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17
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Contreras-Dávila CA, Esveld J, Buisman CJN, Strik DPBTB. nZVI Impacts Substrate Conversion and Microbiome Composition in Chain Elongation From D- and L-Lactate Substrates. Front Bioeng Biotechnol 2021; 9:666582. [PMID: 34211964 PMCID: PMC8239352 DOI: 10.3389/fbioe.2021.666582] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Accepted: 05/25/2021] [Indexed: 12/12/2022] Open
Abstract
Medium-chain carboxylates (MCC) derived from biomass biorefining are attractive biochemicals to uncouple the production of a wide array of products from the use of non-renewable sources. Biological conversion of biomass-derived lactate during secondary fermentation can be steered to produce a variety of MCC through chain elongation. We explored the effects of zero-valent iron nanoparticles (nZVI) and lactate enantiomers on substrate consumption, product formation and microbiome composition in batch lactate-based chain elongation. In abiotic tests, nZVI supported chemical hydrolysis of lactate oligomers present in concentrated lactic acid. In fermentation experiments, nZVI created favorable conditions for either chain-elongating or propionate-producing microbiomes in a dose-dependent manner. Improved lactate conversion rates and n-caproate production were promoted at 0.5-2 g nZVI⋅L-1 while propionate formation became relevant at ≥ 3.5 g nZVI⋅L-1. Even-chain carboxylates (n-butyrate) were produced when using enantiopure and racemic lactate with lactate conversion rates increased in nZVI presence (1 g⋅L-1). Consumption of hydrogen and carbon dioxide was observed late in the incubations and correlated with acetate formation or substrate conversion to elongated products in the presence of nZVI. Lactate racemization was observed during chain elongation while isomerization to D-lactate was detected during propionate formation. Clostridium luticellarii, Caproiciproducens, and Ruminococcaceae related species were associated with n-valerate and n-caproate production while propionate was likely produced through the acrylate pathway by Clostridium novyi. The enrichment of different potential n-butyrate producers (Clostridium tyrobutyricum, Lachnospiraceae, Oscillibacter, Sedimentibacter) was affected by nZVI presence and concentrations. Possible theories and mechanisms underlying the effects of nZVI on substrate conversion and microbiome composition are discussed. An outlook is provided to integrate (bio)electrochemical systems to recycle (n)ZVI and provide an alternative reducing power agent as durable control method.
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Affiliation(s)
| | - Johan Esveld
- Environmental Technology, Wageningen University & Research, Wageningen, Netherlands
| | - Cees J N Buisman
- Environmental Technology, Wageningen University & Research, Wageningen, Netherlands
| | - David P B T B Strik
- Environmental Technology, Wageningen University & Research, Wageningen, Netherlands
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18
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Isipato M, Dessì P, Sánchez C, Mills S, Ijaz UZ, Asunis F, Spiga D, De Gioannis G, Mascia M, Collins G, Muntoni A, Lens PNL. Propionate Production by Bioelectrochemically-Assisted Lactate Fermentation and Simultaneous CO 2 Recycling. Front Microbiol 2021; 11:599438. [PMID: 33384675 PMCID: PMC7769879 DOI: 10.3389/fmicb.2020.599438] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Accepted: 11/23/2020] [Indexed: 11/17/2022] Open
Abstract
Production of volatile fatty acids (VFAs), fundamental building blocks for the chemical industry, depends on fossil fuels but organic waste is an emerging alternative substrate. Lactate produced from sugar-containing waste streams can be further processed to VFAs. In this study, electrofermentation (EF) in a two-chamber cell is proposed to enhance propionate production via lactate fermentation. At an initial pH of 5, an applied potential of −1 V vs. Ag/AgCl favored propionate production over butyrate from 20 mM lactate (with respect to non-electrochemical control incubations), due to the pH buffering effect of the cathode electrode, with production rates up to 5.9 mM d–1 (0.44 g L–1 d–1). Microbial community analysis confirmed the enrichment of propionate-producing microorganisms, such as Tyzzerella sp. and Propionibacterium sp. Organisms commonly found in microbial electrosynthesis reactors, such as Desulfovibrio sp. and Acetobacterium sp., were also abundant at the cathode, indicating their involvement in recycling CO2 produced by lactate fermentation into acetate, as confirmed by stoichiometric calculations. Propionate was the main product of lactate fermentation at substrate concentrations up to 150 mM, with a highest production rate of 12.9 mM d–1 (0.96 g L–1 d–1) and a yield of 0.48 mol mol–1 lactate consumed. Furthermore, as high as 81% of the lactate consumed (in terms of carbon) was recovered as soluble product, highlighting the potential for EF application with high-carbon waste streams, such as cheese whey or other food wastes. In summary, EF can be applied to control lactate fermentation toward propionate production and to recycle the resulting CO2 into acetate, increasing the VFA yield and avoiding carbon emissions and addition of chemicals for pH control.
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Affiliation(s)
- Marco Isipato
- Department of Civil and Environmental Engineering and Architecture, University of Cagliari, Cagliari, Italy.,Microbiology, School of Natural Sciences and Ryan Institute, National University of Ireland Galway, Galway, Ireland
| | - Paolo Dessì
- Microbiology, School of Natural Sciences and Ryan Institute, National University of Ireland Galway, Galway, Ireland
| | - Carlos Sánchez
- Microbiology, School of Natural Sciences and Ryan Institute, National University of Ireland Galway, Galway, Ireland
| | - Simon Mills
- Microbiology, School of Natural Sciences and Ryan Institute, National University of Ireland Galway, Galway, Ireland
| | - Umer Z Ijaz
- Infrastructure and Environment Research Division, School of Engineering, University of Glasgow, Glasgow, United Kingdom
| | - Fabiano Asunis
- Department of Civil and Environmental Engineering and Architecture, University of Cagliari, Cagliari, Italy
| | - Daniela Spiga
- Department of Civil and Environmental Engineering and Architecture, University of Cagliari, Cagliari, Italy
| | - Giorgia De Gioannis
- Department of Civil and Environmental Engineering and Architecture, University of Cagliari, Cagliari, Italy.,IGAG-CNR, Environmental Geology and Geoengineering Institute of the National Research Council-Piazza D'Armi 1, Cagliari, Italy
| | - Michele Mascia
- Dipartimento di Ingegneria Meccanica, Chimica, e dei Materiali, Università degli Studi di Cagliari, Cagliari, Italy
| | - Gavin Collins
- Microbiology, School of Natural Sciences and Ryan Institute, National University of Ireland Galway, Galway, Ireland
| | - Aldo Muntoni
- Department of Civil and Environmental Engineering and Architecture, University of Cagliari, Cagliari, Italy.,IGAG-CNR, Environmental Geology and Geoengineering Institute of the National Research Council-Piazza D'Armi 1, Cagliari, Italy
| | - Piet N L Lens
- Microbiology, School of Natural Sciences and Ryan Institute, National University of Ireland Galway, Galway, Ireland
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