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Cao Y, Liu H, Liu W, Guo J, Xian M. Debottlenecking the biological hydrogen production pathway of dark fermentation: insight into the impact of strain improvement. Microb Cell Fact 2022; 21:166. [PMID: 35986320 PMCID: PMC9389701 DOI: 10.1186/s12934-022-01893-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 07/26/2022] [Indexed: 11/26/2022] Open
Abstract
Confronted with the exhaustion of the earth’s fossil fuel reservoirs, bio-based process to produce renewable energy is receiving significant interest. Hydrogen is considered as an attractive energy carrier that can replace fossil fuels in the future mainly due to its high energy content, recyclability and environment-friendly nature. Biological hydrogen production from renewable biomass or waste materials by dark fermentation is a promising alternative to conventional routes since it is energy-saving and reduces environmental pollution. However, the current yield and evolution rate of fermentative hydrogen production are still low. Strain improvement of the microorganisms employed for hydrogen production is required to make the process competitive with traditional production methods. The present review summarizes recent progresses on the screening for highly efficient hydrogen-producing strains using various strategies. As the metabolic pathways for fermentative hydrogen production have been largely resolved, it is now possible to engineer the hydrogen-producing strains by rational design. The hydrogen yields and production rates by different genetically modified microorganisms are discussed. The key limitations and challenges faced in present studies are also proposed. We hope that this review can provide useful information for scientists in the field of fermentative hydrogen production. Hydrogen can be generated by microorganisms. Dark fermentation is efficient for biological hydrogen production. Strain improvement is critical to enhancing hydrogen-producing ability.
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Yanti NA. Phenotypic Characterization and Identification of Potential L-Asparaginase-Producing Thermohalophilic Bacteria from Wawolesea Hot Spring, North Konawe, Southeast Sulawesi, Indonesia. Pak J Biol Sci 2022; 25:1021-1032. [PMID: 36591934 DOI: 10.3923/pjbs.2022.1021.1032] [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] [Indexed: 12/29/2022]
Abstract
<b>Background and Objective:</b> L-asparaginase-producing thermohalophilic bacteria have the potential of producing an enzyme tolerant to high heat and salt levels. This enzyme, L-asparaginase, can be used as a biological agent for the cancer therapy of acute lymphoblastic leukemia and melanosarcoma as it has a specific ability to inhibit the formation of nutrients for cancer cells. This enzyme is also used effectively in food industries operating at high temperatures due to its ability to reduce acrylamide, a trigger of cancer cells. This study sought to figure out the phenotypic characters of and identify potential L-asparaginase-producing thermohalophilic bacteria from Wawolesea Hot Spring, North Konawe, Southeast Sulawesi. <b>Materials and Methods:</b> The characterization conducted on potential L-asparaginase-producing thermohalophilic bacterial isolates consisted of the following: Colony morphological characterization, covering the shapes, edges, internal structures, elevations and colours of the colonies, cell morphological characterization, covering gram staining, endospore formation and motility, biochemical characterization, covering catalase, Methyl Red and Voges Proskauer (MR-VP), gelatin hydrolysis, citrate, indole and carbohydrate fermentation tests and physiological characterization, covering pH effect, salinity, oxygen demand and temperature effect tests. Bacterial isolate identification was carried out in two stages, namely phenetic identification based on the phenotypic characterization data determine through a preliminary identification and numeric-phenetic identification. <b>Results:</b> The characterization results showed that the bacterial isolates AAT 1.4, AAT 3.2 and CAT 3.4 were <i>bacillus</i>-shaped, Gram-positive, motile, catalase-positive and aerobic. Based on the numeric-phenetic analysis results, the isolates AAT 1.4 and CAT 3.4 had a 92.9% similarity to <i>Bacillus subtilis</i>, while isolate AAT 3.2 had a 92.9% similarity to <i>Brevibacillus limnophilus</i>. <b>Conclusion:</b> According to the numeric-phenetic analysis results, the isolates AAT 1.4 and CAT 3.4 belong to the species <i>Bacillus subtilis</i>, while isolate AAT 3.2 belongs to the species <i>Brevibacillus limnophilus</i>.
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The physiology and biotechnology of dark fermentative biohydrogen production. Biotechnol Adv 2018; 36:2165-2186. [DOI: 10.1016/j.biotechadv.2018.10.005] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Revised: 08/31/2018] [Accepted: 10/08/2018] [Indexed: 02/02/2023]
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Immobilization of Enterobacter aerogenes by a Trimeric Autotransporter Adhesin, AtaA, and Its Application to Biohydrogen Production. Catalysts 2018. [DOI: 10.3390/catal8040159] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Biological hydrogen production by microbial cells has been extensively researched as an energy-efficient and environmentally-friendly process. In this study, we propose a fast, easy method for immobilizing Enterobacter aerogenes by expressing ataA, which encodes the adhesive protein of Acinetobacter sp. Tol 5. AtaA protein on the E. aerogenes cells carrying the ataA gene was demonstrated by immunoblotting and flow cytometry. The AtaA-producing cells exhibited stronger adherence and auto-agglutination characteristics than wild-type cells, and were successfully immobilized (at approximately 2.5 mg/cm3) on polyurethane foam. Hydrogen production from the cell-immobilized polyurethane foams was monitored in repetitive batch reactions and flow reactor studies. The total hydrogen production in triple-repetitive batch reactions reached 0.6 mol/mol glucose, and the hydrogen production rate in the flow reactor was 42 mL·h−1·L−1. The AtaA production achieved simple and immediate immobilization of E. aerogenes on the foam, enabling repetitive and continuous hydrogen production. This report newly demonstrates the production of AtaA on the cell surfaces of bacterial genera other than Acinetobacter, and can simplify and accelerate the immobilization of whole-cell catalysts.
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Perturbation of formate pathway and NADH pathway acting on the biohydrogen production. Sci Rep 2017; 7:9587. [PMID: 28852065 PMCID: PMC5575262 DOI: 10.1038/s41598-017-10191-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Accepted: 08/03/2017] [Indexed: 11/21/2022] Open
Abstract
The formate pathway and NADH pathway as two common hydrogen-producing metabolic pathways have been well characterized to understand and improve biohydrogen production. These two pathways have been thought to be separate and have been independently investigated. However, in this study, perturbation of genes (hycA, fdhF, fhlA, ldhA, nuoB, hybO, fdh1, narP, and ppk) in Enterobacter aerogenes related to the formate pathway or NADH pathway revealed that these two pathways affected each other. Further metabolic analysis suggested that a linear relationship existed between the relative change of hydrogen yield in the formate pathway or NADH pathway and the relative change of NADH yield or ATP yield. Thus, this finding provides new insight into the role of cellular reducing power and energy level in the hydrogen metabolism. It also establishes a rationale for improving hydrogen production from a global perspective.
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Jawed M, Pi J, Xu L, Zhang H, Hakeem A, Yan Y. Enhanced H2 Production and Redirected Metabolic Flux via Overexpression of fhlA and pncB in Klebsiella HQ-3 Strain. Appl Biochem Biotechnol 2015; 178:1113-28. [PMID: 26590848 DOI: 10.1007/s12010-015-1932-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Accepted: 11/16/2015] [Indexed: 11/26/2022]
Abstract
Genetic modifications are considered as one of the most important technologies for improving fermentative hydrogen yield. Herein, we overexpress fhlA and pncB genes from Klebsiella HQ-3 independently to enhance hydrogen molar yield. HQ-3-fhlA/pncB strain is developed by manipulation of pET28-Pkan/fhlA Kan(r) and pBBR1-MCS5/pncB Gm(r) as expression vectors to examine the synchronous effects of fhlA and pncB. Optimization of anaerobic batch fermentations is achieved and the maximum yield of biohydrogen (1.42 mol H2/mol of glucose) is produced in the range of pH 6.5-7.0 at 33-37 °C. Whole cell H2 yield is increased up to 40 % from HQ-3-fhlA/pncB, as compared with HQ-3-fhlA 20 % and HQ-3-pncB 12 % keeping HQ-3-C as a control. Mechanism of improved H2 yield is studied in combination with metabolic flux analysis by measuring glucose consumption and other metabolites including formate, succinate, 2,3 butanediol, lactate, acetate, ethanol, and hydrogen. The results suggest that under transient conditions, the increase in the total level of NAD by NAPRTase can enhance the rate of NADH-dependent pathways, and therefore, final distribution of metabolites is changed. Combined overexpression of fhlA and pncB eventually modifies the energy and carbon balance leading to enhanced H2 production from FHL as well as by NADH pathway.
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Affiliation(s)
- Muhammad Jawed
- Key Laboratory of Molecular Biophysics, the Ministry of Education, Huazhong University of Science and Technology, Wuhan, 430074, People's Republic of China
| | - Jian Pi
- Key Laboratory of Molecular Biophysics, the Ministry of Education, Huazhong University of Science and Technology, Wuhan, 430074, People's Republic of China
| | - Li Xu
- Key Laboratory of Molecular Biophysics, the Ministry of Education, Huazhong University of Science and Technology, Wuhan, 430074, People's Republic of China
- College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, 430074, People's Republic of China
| | - Houjin Zhang
- Key Laboratory of Molecular Biophysics, the Ministry of Education, Huazhong University of Science and Technology, Wuhan, 430074, People's Republic of China
- College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, 430074, People's Republic of China
| | - Abdul Hakeem
- College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, 430074, People's Republic of China
| | - Yunjun Yan
- Key Laboratory of Molecular Biophysics, the Ministry of Education, Huazhong University of Science and Technology, Wuhan, 430074, People's Republic of China.
- College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, 430074, People's Republic of China.
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Pi J, Jawed M, Wang J, Xu L, Yan Y. Mutational analysis of the hyc-operon determining the relationship between hydrogenase-3 and NADH pathway in Enterobacter aerogenes. Enzyme Microb Technol 2015; 82:1-7. [PMID: 26672442 DOI: 10.1016/j.enzmictec.2015.08.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Revised: 08/14/2015] [Accepted: 08/17/2015] [Indexed: 10/23/2022]
Abstract
In this study, the hydrogenase-3 gene cluster (hycDEFGH) was isolated and identified from Enterobacter aerogenes CCTCC AB91102. All gene products were highly homologous to the reported bacterial hydrogenase-3 (Hyd-3) proteins. The genes hycE, hycF, hycG encoding the subunits of hydrogenase-3 were targeted for genetic knockout to inhibit the FHL hydrogen production pathway via the Red recombination system, generating three mutant strains AB91102-E (ΔhycE), AB91102-F (ΔhycF) and AB91102-G (ΔhycG). Deletion of the three genes affected the integrity of hydrogenase-3. The hydrogen production experiments with the mutant strains showed that no hydrogen was detected compared with the wild type (0.886 mol/mol glucose), demonstrating that knocking out any of the three genes could inhibit NADH hydrogen production pathway. Meanwhile, the metabolites of the mutant strains were significantly changed in comparison with the wild type, indicating corresponding changes in metabolic flux by mutation. Additionally, the activity of NADH-mediated hydrogenase was found to be nil in the mutant strains. The chemostat experiments showed that the NADH/NAD(+) ratio of the mutant strains increased nearly 1.4-fold compared with the wild type. The NADH-mediated hydrogenase activity and NADH/NAD(+) ratio analysis both suggested that NADH pathway required the involvement of the electron transport chain of hydrogenase-3.
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Affiliation(s)
- Jian Pi
- Key Laboratory of Molecular Biophysics, the Ministry of Education, Huazhong University of Science and Technology, Wuhan 430074, PR China; College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, PR China
| | - Muhammad Jawed
- Key Laboratory of Molecular Biophysics, the Ministry of Education, Huazhong University of Science and Technology, Wuhan 430074, PR China; College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, PR China
| | - Jun Wang
- Key Laboratory of Molecular Biophysics, the Ministry of Education, Huazhong University of Science and Technology, Wuhan 430074, PR China; College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, PR China
| | - Li Xu
- Key Laboratory of Molecular Biophysics, the Ministry of Education, Huazhong University of Science and Technology, Wuhan 430074, PR China; College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, PR China.
| | - Yunjun Yan
- Key Laboratory of Molecular Biophysics, the Ministry of Education, Huazhong University of Science and Technology, Wuhan 430074, PR China; College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, PR China.
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Impact of an energy-conserving strategy on succinate production under weak acidic and anaerobic conditions in Enterobacter aerogenes. Microb Cell Fact 2015; 14:80. [PMID: 26063229 PMCID: PMC4464251 DOI: 10.1186/s12934-015-0269-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Accepted: 05/25/2015] [Indexed: 11/10/2022] Open
Abstract
Background Succinate is an important C4 building block chemical, and its production via fermentative processes in bacteria has many practical applications in the biotechnology field. One of the major goals of optimizing the bacterium-based succinate production process is to lower the culture pH from the current neutral conditions, as this would reduce total production costs. In our previous studies, we selected Enterobacter aerogenes, a rapid glucose assimilator at pH 5.0, in order to construct a metabolically engineered strain that could produce succinate under weakly acidic conditions. This engineered strain produced succinate from glucose with a 72.7% (g/g) yield at pH 5.7, with a volumetric productivity of 0.23 g/L/h. Although this demonstrates proof-of-concept that bacterium-based succinate fermentation can be improved under weakly acidic conditions, several parameters still required further optimization. Results In this study, we genetically modified an E. aerogenes strain previously developed in our laboratory in order to increase the production of ATP during succinate synthesis, as we inferred that this would positively impact succinate biosynthesis. This led to the development of the ES08ΔptsG strain, which contains the following modifications: chromosomally expressed Actinobacillus succinogenes phosphoenolpyruvate carboxykinase, enhanced fumarate reductase, inactivated pyruvate formate lyase, pyruvate oxidase, and glucose-phosphotransferase permease (enzyme IIBCGlc). This strain produced 55.4 g/L succinate from glucose, with 1.8 g/L acetate as the major byproduct at pH 5.7 and anaerobic conditions. The succinate yield and volumetric productivity of this strain were 86.8% and 0.92 g/L/h, respectively. Conclusions Focusing on increasing net ATP production during succinate synthesis leads to increased succinate yield and volumetric productivity in E. aerogenes. We propose that the metabolically engineered E. aerogenes ES08ΔptsG strain, which effectively produces succinate under weakly acidic and anaerobic conditions, has potential utility for economical succinate production.
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Study of the role of anaerobic metabolism in succinate production by Enterobacter aerogenes. Appl Microbiol Biotechnol 2014; 98:7803-13. [PMID: 24962116 DOI: 10.1007/s00253-014-5884-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Revised: 06/04/2014] [Accepted: 06/05/2014] [Indexed: 10/25/2022]
Abstract
Succinate is a core biochemical building block; optimizing succinate production from biomass by microbial fermentation is a focus of basic and applied biotechnology research. Lowering pH in anaerobic succinate fermentation culture is a cost-effective and environmentally friendly approach to reducing the use of sub-raw materials such as alkali, which are needed for neutralization. To evaluate the potential of bacteria-based succinate fermentation under weak acidic (pH <6.2) and anaerobic conditions, we characterized the anaerobic metabolism of Enterobacter aerogenes AJ110637, which rapidly assimilates glucose at pH 5.0. Based on the profile of anaerobic products, we constructed single-gene knockout mutants to eliminate the main anaerobic metabolic pathways involved in NADH re-oxidation. These single-gene knockout studies showed that the ethanol synthesis pathway serves as the dominant NADH re-oxidation pathway in this organism. To generate a metabolically engineered strain for succinate production, we eliminated ethanol formation and introduced a heterogeneous carboxylation enzyme, yielding E. aerogenes strain ΔadhE/PCK. The strain produced succinate from glucose with a 60.5% yield (grams of succinate produced per gram of glucose consumed) at pH <6.2 and anaerobic conditions. Thus, we showed the potential of bacteria-based succinate fermentation under weak acidic conditions.
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Ethanol production from glycerol-containing biodiesel waste by Klebsiella variicola shows maximum productivity under alkaline conditions. N Biotechnol 2014; 31:246-53. [DOI: 10.1016/j.nbt.2014.03.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2013] [Revised: 01/09/2014] [Accepted: 03/06/2014] [Indexed: 11/18/2022]
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Rittmann S, Herwig C. A comprehensive and quantitative review of dark fermentative biohydrogen production. Microb Cell Fact 2012; 11:115. [PMID: 22925149 PMCID: PMC3443015 DOI: 10.1186/1475-2859-11-115] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2012] [Accepted: 08/03/2012] [Indexed: 01/25/2023] Open
Abstract
Biohydrogen production (BHP) can be achieved by direct or indirect biophotolysis, photo-fermentation and dark fermentation, whereof only the latter does not require the input of light energy. Our motivation to compile this review was to quantify and comprehensively report strains and process performance of dark fermentative BHP. This review summarizes the work done on pure and defined co-culture dark fermentative BHP since the year 1901. Qualitative growth characteristics and quantitative normalized results of H2 production for more than 2000 conditions are presented in a normalized and therefore comparable format to the scientific community.Statistically based evidence shows that thermophilic strains comprise high substrate conversion efficiency, but mesophilic strains achieve high volumetric productivity. Moreover, microbes of Thermoanaerobacterales (Family III) have to be preferred when aiming to achieve high substrate conversion efficiency in comparison to the families Clostridiaceae and Enterobacteriaceae. The limited number of results available on dark fermentative BHP from fed-batch cultivations indicates the yet underestimated potential of this bioprocessing application. A Design of Experiments strategy should be preferred for efficient bioprocess development and optimization of BHP aiming at improving medium, cultivation conditions and revealing inhibitory effects. This will enable comparing and optimizing strains and processes independent of initial conditions and scale.
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Affiliation(s)
- Simon Rittmann
- Institute of Chemical Engineering, Research Area Biochemical Engineering, Gumpendorferstraße 1a, Vienna University of Technology, Vienna, 1060, Austria
| | - Christoph Herwig
- Institute of Chemical Engineering, Research Area Biochemical Engineering, Gumpendorferstraße 1a, Vienna University of Technology, Vienna, 1060, Austria
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Zhang C, Lv FX, Xing XH. Bioengineering of the Enterobacter aerogenes strain for biohydrogen production. BIORESOURCE TECHNOLOGY 2011; 102:8344-8349. [PMID: 21764301 DOI: 10.1016/j.biortech.2011.06.018] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2010] [Revised: 06/03/2011] [Accepted: 06/04/2011] [Indexed: 05/31/2023]
Abstract
Enterobacter aerogenes is one of the most widely-studied model strains for fermentative hydrogen production. To improve the hydrogen yield of E. aerogenes, the bioengineering on a biomolecular level and metabolic network level is of importance. In this review, the fermentative technology of E. aerogenes for hydrogen production will be first briefly summarized. And then the bioengineering of E. aerogenes for the improvement of hydrogen yield will be thoroughly reviewed, including the anaerobic metabolic networks for hydrogen evolution in E. aerogenes, metabolic engineering for improving hydrogen production in E. aerogenes and mixed culture of E. aerogenes with other hydrogen-producing bacteria to enhance the overall yield in anaerobic cultivation. Finally, a perspective on E. aerogenes as a hydrogen producer including systems bioengineering approach for improving the hydrogen yield and application of the engineered E. aerogenes in mixed culture will be presented.
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Affiliation(s)
- Chong Zhang
- Department of Chemical Engineering, Tsinghua University, Beijing 100084, PR China
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Xiong Y, Liu J, Yang GF, Zhan CG. Computational determination of fundamental pathway and activation barriers for acetohydroxyacid synthase-catalyzed condensation reactions of α-keto acids. J Comput Chem 2009; 31:1592-602. [DOI: 10.1002/jcc.21356] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Nishio N, Nakashimada Y. Recent development of anaerobic digestion processes for energy recovery from wastes. J Biosci Bioeng 2007; 103:105-12. [PMID: 17368391 DOI: 10.1263/jbb.103.105] [Citation(s) in RCA: 113] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2006] [Accepted: 11/29/2006] [Indexed: 11/17/2022]
Abstract
Anaerobic digestion leads to the overall gasification of organic wastewaters and wastes, and produces methane and carbon dioxide; this gasification contributes to reducing organic matter and recovering energy from organic carbons. Here, we propose three new processes and demonstrate the effectiveness of each process. By using complete anaerobic organic matter removal process (CARP), in which diluted wastewaters such as sewage and effluent from a methane fermentation digester were treated under anaerobic condition for post-treatment, the chemical oxygen demand (COD) in wastewater was decreased to less than 20 ppm. The dry ammonia-methane two-stage fermentation process (Am-Met process) is useful for the anaerobic treatment of nitrogen-rich wastes such as waste excess sludge, cow feces, chicken feces, and food waste without the dilution of the ammonia produced by water or carbon-rich wastes. The hydrogen-methane two-stage fermentation (Hy-Met process), in which the hydrogen produced in the first stage is used for a fuel cell system to generate electricity and the methane produced in the second stage is used to generate heat energy to heat the two reactors and satisfy heat requirements, is useful for the treatment of sugar-rich wastewaters, bread wastes, and biodiesel wastewaters.
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Affiliation(s)
- Naomichi Nishio
- Department of Molecular Biotechnology, Graduate School of Advanced Sciences of Matter, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8530, Japan.
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Matsumoto M, Nishimura Y. Hydrogen production by fermentation using acetic acid and lactic acid. J Biosci Bioeng 2007; 103:236-41. [PMID: 17434426 DOI: 10.1263/jbb.103.236] [Citation(s) in RCA: 102] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2006] [Accepted: 12/07/2006] [Indexed: 11/17/2022]
Abstract
Microbial hydrogen production from sho-chu post-distillation slurry solution (slurry solution) containing large amounts of organic acids was investigated. The highest hydrogen producer, Clostridium diolis JPCC H-3, was isolated from natural environment and produced hydrogen at 6.03+/-0.15 ml from 5 ml slurry solution in 30 h. Interestingly, the concentration of acetic acid and lactic acid in the slurry solution decreased during hydrogen production. The substrates for hydrogen production by C. diolis JPCC H-3, in particular organic acids, were investigated in an artificial medium. No hydrogen was produced from acetic acid, propionic acid, succinic acid, or citric acid on their own. Hydrogen and butyric acid were produced from a mixture of acetic acid and lactic acid, showing that C. diolis. JPCC H-3 could produce hydrogen from acetic acid and lactic acid. Furthermore, calculation of the Gibbs free energy strongly suggests that this reaction would proceed. In this paper, we describe for the first time microbial hydrogen production from acetic acid and lactic acid by fermentation.
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Affiliation(s)
- Mitsufumi Matsumoto
- Technology Development Center, Wakamatsu Research Institute, Biotechnology Laboratory, Electric Power Development Co., Ltd, 1 Yanagasaki, Wakamatsu, Kitakyushu, Fukuoka 808-0111, Japan.
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Ren N, Gong M. Acclimation Strategy of a Biohydrogen Producing Population in a Continuous-Flow Reactor with Carbohydrate Fermentation. Eng Life Sci 2006. [DOI: 10.1002/elsc.200520140] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Ito T, Nakashimada Y, Senba K, Matsui T, Nishio N. Hydrogen and ethanol production from glycerol-containing wastes discharged after biodiesel manufacturing process. J Biosci Bioeng 2005; 100:260-5. [PMID: 16243274 DOI: 10.1263/jbb.100.260] [Citation(s) in RCA: 180] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2004] [Accepted: 05/13/2005] [Indexed: 11/17/2022]
Abstract
H2 and ethanol production from glycerol-containing wastes discharged after a manufacturing process for biodiesel fuel (biodiesel wastes) using Enterobacter aerogenes HU-101 was evaluated. The biodiesel wastes should be diluted with a synthetic medium to increase the rate of glycerol utilization and the addition of yeast extract and tryptone to the synthetic medium accelerated the production of H2 and ethanol. The yields of H2 and ethanol decreased with an increase in the concentrations of biodiesel wastes and commercially available glycerol (pure glycerol). Furthermore, the rates of H2 and ethanol production from biodiesel wastes were much lower than those at the same concentration of pure glycerol, partially due to a high salt content in the wastes. In continuous culture with a packed-bed reactor using self-immobilized cells, the maximum rate of H2 production from pure glycerol was 80 mmol/l/h yielding ethanol at 0.8 mol/mol-glycerol, while that from biodiesel wastes was only 30 mmol/l/h. However, using porous ceramics as a support material to fix cells in the reactor, the maximum H2 production rate from biodiesel wastes reached 63 mmol/l/h obtaining an ethanol yield of 0.85 mol/mol-glycerol.
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Affiliation(s)
- Takeshi Ito
- Department of Molecular Biotechnology, Graduate School of Advanced Sciences of Matter, Hiroshima University, Japan
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