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Dai K, Qu C, Feng J, Lan Y, Fu H, Wang J. Metabolic engineering of Thermoanaerobacterium aotearoense strain SCUT27 for biofuels production from sucrose and molasses. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2023; 16:155. [PMID: 37865803 PMCID: PMC10589968 DOI: 10.1186/s13068-023-02402-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2023] [Accepted: 09/21/2023] [Indexed: 10/23/2023]
Abstract
BACKGROUND Sucrose-rich sugarcane trash surpasses 28 million tons globally per year. Effective biorefinery systems could convert these biomasses to bioproducts, such as bioethanol from sugarcane sucrose in Brazil. Thermophilic microbes for biofuels have attracted great attention due to their higher fermentation temperature and wide substrate spectrum. However, few thermophiles using sucrose or molasses for biofuels production was reported. Thermoanaerobacterium aotearoense SCUT27 has been considered as an efficient ethanol producer, but it cannot directly utilize sucrose. In this study, various sucrose metabolic pathways were introduced and analyzed in Thermoanaerobaterium. RESULTS The sucrose-6-phosphate hydrolase (scrB), which was from a screened strain Thermoanaerobacterium thermosaccharolyticum G3-1 was overexpressed in T. aotearoense SCUT27 and endowed this strain with the ability to utilize sucrose. In addition, overexpression of the sucrose-specific PTS system (scrA) from Clostridium acetobutylicum accelerated the sucrose transport. To strengthen the alcohols production and substrates metabolism, the redox-sensing transcriptional repressor (rex) in T. aotearoense was further knocked out. Moreover, with the gene arginine repressor (argR) deleted, the ethanologenic mutant P8S10 showed great inhibitors-tolerance and finally accumulated ~ 34 g/L ethanol (a yield of 0.39 g/g sugars) from pretreated cane molasses in 5 L tank by fed-batch fermentation. When introducing butanol synthetic pathway, 3.22 g/L butanol was produced by P8SB4 with a yield of 0.44 g alcohols/g sugars at 50℃. This study demonstrated the potential application of T. aotearoense SCUT27 for ethanol and butanol production from low cost cane molasses. CONCLUSIONS Our work provided strategies for sucrose utilization in thermophiles and improved biofuels production as well as stress tolerances of T. aotearoense SCUT27, demonstrating the potential application of the strain for cost-effective biofuels production from sucrose-based feedstocks.
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Affiliation(s)
- Kaiqun Dai
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, 510006, China
| | - Chunyun Qu
- College of Light Industry and Food Science, Guangdong Provincial Key Laboratory of Science and Technology of Lingnan Special Food Science and Technology, Zhongkai University of Agriculture and Engineering, Guangzhou, 510225, China
| | - Jun Feng
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, 510006, China
| | - Yang Lan
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, 510006, China
| | - Hongxin Fu
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, 510006, China.
- Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, South China University of Technology, Guangzhou, 510006, China.
| | - Jufang Wang
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, 510006, China.
- Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, South China University of Technology, Guangzhou, 510006, China.
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Lu J, Jiang W, Dong W, Zhou J, Zhang W, Jiang Y, Xin F, Jiang M. Construction of a Microbial Consortium for the De Novo Synthesis of Butyl Butyrate from Renewable Resources. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2023; 71:3350-3361. [PMID: 36734010 DOI: 10.1021/acs.jafc.2c07650] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Butyl butyrate has shown wide applications in food, cosmetic, and biofuel sectors. Currently, biosynthesis of butyl butyrate still requires exogenous addition of precursors and lipase, which increases the production cost and limits further large-scale development. In this study, a microbial consortium was first designed to realize direct butyl butyrate production from lignocellulose. The highest butyl butyrate concentration of 34.42 g/L was detected in the solvent phase from 60 g/L glucose using a microbial coculture system composed of Clostridium acetobutylicum NJ4 and Clostridium tyrobutyricum LD with the elimination of butyric acid supplementation. Meanwhile, 13.52 g/L butyl butyrate was synthesized from 60 g/L glucose using a microbial consortium composed of three strains including strain NJ4, strain LD, and Escherichia coli BL21- pET-29a(+)-LE without the addition of any exogenous precursors and lipase. In addition, 2.94 g/L butyl butyrate could be directly produced from 60 g/L microcrystalline cellulose when Trichoderma asperellum was added to the above-mentioned three-strain microbial consortium. This four-strain microbial consortium represents the first study regarding the direct butyl butyrate production from lignocellulose without the supplementation of exogenous precursors and lipase, which may be extended to the biosynthesis of other short-chain esters, such as ethyl acetate and butyl lactate.
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Affiliation(s)
- Jiasheng Lu
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, P. R. China
| | - Wankui Jiang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, P. R. China
| | - Weiliang Dong
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, P. R. China
- Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing 211816, P. R. China
| | - Jie Zhou
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, P. R. China
- Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing 211816, P. R. China
| | - Wenming Zhang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, P. R. China
- Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing 211816, P. R. China
| | - Yujia Jiang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, P. R. China
| | - Fengxue Xin
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, P. R. China
- Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing 211816, P. R. China
| | - Min Jiang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, P. R. China
- Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing 211816, P. R. China
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3
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Re A, Mazzoli R. Current progress on engineering microbial strains and consortia for production of cellulosic butanol through consolidated bioprocessing. Microb Biotechnol 2022; 16:238-261. [PMID: 36168663 PMCID: PMC9871528 DOI: 10.1111/1751-7915.14148] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Revised: 08/01/2022] [Accepted: 09/07/2022] [Indexed: 01/27/2023] Open
Abstract
In the last decades, fermentative production of n-butanol has regained substantial interest mainly owing to its use as drop-in-fuel. The use of lignocellulose as an alternative to traditional acetone-butanol-ethanol fermentation feedstocks (starchy biomass and molasses) can significantly increase the economic competitiveness of biobutanol over production from non-renewable sources (petroleum). However, the low cost of lignocellulose is offset by its high recalcitrance to biodegradation which generally requires chemical-physical pre-treatment and multiple bioreactor-based processes. The development of consolidated processing (i.e., single-pot fermentation) can dramatically reduce lignocellulose fermentation costs and promote its industrial application. Here, strategies for developing microbial strains and consortia that feature both efficient (hemi)cellulose depolymerization and butanol production will be depicted, that is, rational metabolic engineering of native (hemi)cellulolytic or native butanol-producing or other suitable microorganisms; protoplast fusion of (hemi)cellulolytic and butanol-producing strains; and co-culture of (hemi)cellulolytic and butanol-producing microbes. Irrespective of the fermentation feedstock, biobutanol production is inherently limited by the severe toxicity of this solvent that challenges process economic viability. Hence, an overview of strategies for developing butanol hypertolerant strains will be provided.
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Affiliation(s)
- Angela Re
- Centre for Sustainable Future TechnologiesFondazione Istituto Italiano di TecnologiaTorinoItaly,Department of Applied Science and TechnologyPolitecnico di TorinoTurinItaly
| | - Roberto Mazzoli
- Structural and Functional Biochemistry, Laboratory of Proteomics and Metabolic Engineering of Prokaryotes, Department of Life Sciences and Systems BiologyUniversity of TorinoTorinoItaly
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4
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Li R, Wang Z, Kong KW, Xiang P, He X, Zhang X. Probiotic fermentation improves the bioactivities and bioaccessibility of polyphenols in Dendrobium officinale under in vitro simulated gastrointestinal digestion and fecal fermentation. Front Nutr 2022; 9:1005912. [PMID: 36159468 PMCID: PMC9491275 DOI: 10.3389/fnut.2022.1005912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Accepted: 08/16/2022] [Indexed: 11/13/2022] Open
Abstract
The objective of the research was to investigate and compare the bioactivities and bioaccessibility of the polyphenols (PPs) from Dendrobium officinale (DO) and probiotic fermented Dendrobium officinale (FDO), by using in vitro simulated digestion model under oral, gastric and intestinal phases as well as colonic fermentation. The results indicated that FDO possessed significantly higher total phenolic contents (TPC) and total flavonoid contents (TFC) than DO, and they were released most in the intestinal digestion phase with 6.96 ± 0.99 mg GAE/g DE and 10.70 ± 1.31 mg RE/g DE, respectively. Using high-performance liquid chromatography (HPLC), a total of six phenolic acids and four flavonoids were detected. In the intestinal phase, syringaldehyde and ferulic acid were major released by DO, whereas they were p-hydroxybenzoic acid, vanillic acid, and syringic acid for FDO. However, apigenin and scutellarin were sustained throughout the digestion whether DO or FDO. As the digestive process progressed, their antioxidant ability, α-amylase and α-glucosidase inhibitory activities were increased, and FDO was overall substantially stronger in these activities than that of DO. Both DO and FDO could reduce pH values in the colonic fermentation system, and enhance the contents of short-chain fatty acids, but there were no significantly different between them. The results of the 16S rRNA gene sequence analysis showed that both DO and FDO could alter intestinal microbial diversity during in vitro colonic fermentation. In particular, after colonic fermentation for 24 h, FDO could significantly improve the ratio of Firmicutes to Bacteroidetes, and enrich the abundancy of Enterococcus and Bifidobacterium (p < 0.05), which was most likely through the carbohydrate metabolism signal pathway. Taken together, the PPs from DO and FDO had good potential for antioxidant and modulation of gut bacterial flora during the digestive processes, and FDO had better bioactivities and bioaccessibility. This study could provide scientific data and novel insights for Dendrobium officinale to be developed as functional foods.
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Affiliation(s)
- Rurui Li
- Key Laboratory for Forest Resources Conservation and Utilization in the Southwest Mountains of China, Ministry of Education, Southwest Forestry University, Kunming, China
- College of Life Science, Southwest Forestry University, Kunming, China
| | - Zhenxing Wang
- Key Laboratory for Forest Resources Conservation and Utilization in the Southwest Mountains of China, Ministry of Education, Southwest Forestry University, Kunming, China
- College of Life Science, Southwest Forestry University, Kunming, China
| | - Kin Weng Kong
- Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Ping Xiang
- Institute of Environmental Remediation and Human Health, Southwest Forestry University, Kunming, China
| | - Xiahong He
- Key Laboratory for Forest Resources Conservation and Utilization in the Southwest Mountains of China, Ministry of Education, Southwest Forestry University, Kunming, China
- College of Horticulture and Landscape, Southwest Forestry University, Kunming, China
- *Correspondence: Xiahong He
| | - Xuechun Zhang
- Key Laboratory for Forest Resources Conservation and Utilization in the Southwest Mountains of China, Ministry of Education, Southwest Forestry University, Kunming, China
- College of Life Science, Southwest Forestry University, Kunming, China
- Xuechun Zhang
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5
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Guo Y, Liu Y, Guan M, Tang H, Wang Z, Lin L, Pang H. Production of butanol from lignocellulosic biomass: recent advances, challenges, and prospects. RSC Adv 2022; 12:18848-18863. [PMID: 35873330 PMCID: PMC9240921 DOI: 10.1039/d1ra09396g] [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: 12/28/2021] [Accepted: 05/27/2022] [Indexed: 11/21/2022] Open
Abstract
Due to energy and environmental concerns, biobutanol is gaining increasing attention as an alternative renewable fuel owing to its desirable fuel properties. Biobutanol production from lignocellulosic biomass through acetone-butanol-ethanol (ABE) fermentation has gained much interest globally due to its sustainable supply and non-competitiveness with food, but large-scale fermentative production suffers from low product titres and poor selectivity. This review presents recent developments in lignocellulosic butanol production, including pretreatment and hydrolysis of hemicellulose and cellulose during ABE fermentation. Challenges are discussed, including low concentrations of fermentation sugars, inhibitors, detoxification, and carbon catabolite repression. Some key process improvements are also summarised to guide further research and development towards more profitable and commercially viable butanol fermentation.
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Affiliation(s)
- Yuan Guo
- National Engineering Research Center for Non-Food Biorefinery, State Key Laboratory of Non-Food Biomass and Enzyme Technology, Guangxi Key Laboratory of Bio-refinery, Guangxi Academy of Sciences 98 Daling Road Nanning 530007 China +86-771-2503940 +86-771-2503973
| | - Yi Liu
- National Engineering Research Center for Non-Food Biorefinery, State Key Laboratory of Non-Food Biomass and Enzyme Technology, Guangxi Key Laboratory of Bio-refinery, Guangxi Academy of Sciences 98 Daling Road Nanning 530007 China +86-771-2503940 +86-771-2503973
| | - Mingdong Guan
- College of Life Science and Technology, Guangxi University Nanning 530004 China
| | - Hongchi Tang
- National Engineering Research Center for Non-Food Biorefinery, State Key Laboratory of Non-Food Biomass and Enzyme Technology, Guangxi Key Laboratory of Bio-refinery, Guangxi Academy of Sciences 98 Daling Road Nanning 530007 China +86-771-2503940 +86-771-2503973
| | - Zilong Wang
- National Engineering Research Center for Non-Food Biorefinery, State Key Laboratory of Non-Food Biomass and Enzyme Technology, Guangxi Key Laboratory of Bio-refinery, Guangxi Academy of Sciences 98 Daling Road Nanning 530007 China +86-771-2503940 +86-771-2503973
| | - Lihua Lin
- National Engineering Research Center for Non-Food Biorefinery, State Key Laboratory of Non-Food Biomass and Enzyme Technology, Guangxi Key Laboratory of Bio-refinery, Guangxi Academy of Sciences 98 Daling Road Nanning 530007 China +86-771-2503940 +86-771-2503973
| | - Hao Pang
- National Engineering Research Center for Non-Food Biorefinery, State Key Laboratory of Non-Food Biomass and Enzyme Technology, Guangxi Key Laboratory of Bio-refinery, Guangxi Academy of Sciences 98 Daling Road Nanning 530007 China +86-771-2503940 +86-771-2503973
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6
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Singhania RR, Patel AK, Singh A, Haldar D, Soam S, Chen CW, Tsai ML, Dong CD. Consolidated bioprocessing of lignocellulosic biomass: Technological advances and challenges. BIORESOURCE TECHNOLOGY 2022; 354:127153. [PMID: 35421566 DOI: 10.1016/j.biortech.2022.127153] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Revised: 04/08/2022] [Accepted: 04/09/2022] [Indexed: 06/14/2023]
Abstract
Consolidated bioprocessing (CBP) is characterized by a single-step production of value-added compounds directly from biomass in a single vessel. This strategy has the capacity to revolutionize the whole biorefinery concept as it can significantly reduce the infrastructure input and use of chemicals for various processing steps which can make it economically and environmentally benign. Although the proof of concept has been firmly established in the past, commercialization has been limited due to the low conversion efficiency of the technology. Either a native single microbe, genetically modified microbe or a consortium can be employed. The major challenge in developing a cost-effective and feasible CBP process is the recognition of bifunctional catalysts combining the capability to use the substrates and transform them into value-added products with high efficiency. This article presents an in-depth analysis of the current developments in CBP around the globe and the possibilities of advancements in the future.
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Affiliation(s)
- Reeta Rani Singhania
- Department of Marine Environmental Engineering, National Kaohsiung University of Science and Technology, Kaohsiung City, Taiwan; Centre for Energy and Environmental Sustainability, Lucknow 226 029, India
| | - Anil Kumar Patel
- Department of Marine Environmental Engineering, National Kaohsiung University of Science and Technology, Kaohsiung City, Taiwan; Centre for Energy and Environmental Sustainability, Lucknow 226 029, India
| | - Anusuiya Singh
- Department of Marine Environmental Engineering, National Kaohsiung University of Science and Technology, Kaohsiung City, Taiwan
| | - Dibyajyoti Haldar
- Department of Biotechnology, Karunya Institute of Technology and Sciences, Coimbatore, Tamil Nadu 641114, India
| | - Shveta Soam
- Department of Building Engineering, Energy Systems and Sustainability Science, University of Gävle, Kungsbäcksvägen 47, 80176 Gävle, Sweden
| | - Chiu-Wen Chen
- Department of Marine Environmental Engineering, National Kaohsiung University of Science and Technology, Kaohsiung City, Taiwan; Institute of Aquatic Science and Technology, National Kaohsiung University of Science and Technology, Kaohsiung City, Taiwan
| | - Mei-Ling Tsai
- Department of Seafood Science, National Kaohsiung University of Science and Technology, Kaohsiung City, Taiwan
| | - Cheng-Di Dong
- Department of Marine Environmental Engineering, National Kaohsiung University of Science and Technology, Kaohsiung City, Taiwan; Institute of Aquatic Science and Technology, National Kaohsiung University of Science and Technology, Kaohsiung City, Taiwan.
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7
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Son J, Joo JC, Baritugo KA, Jeong S, Lee JY, Lim HJ, Lim SH, Yoo JI, Park SJ. Consolidated microbial production of four-, five-, and six-carbon organic acids from crop residues: Current status and perspectives. BIORESOURCE TECHNOLOGY 2022; 351:127001. [PMID: 35292386 DOI: 10.1016/j.biortech.2022.127001] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Revised: 03/08/2022] [Accepted: 03/09/2022] [Indexed: 06/14/2023]
Abstract
The production of platform organic acids has been heavily dependent on petroleum-based industries. However, petrochemical-based industries that cannot guarantee a virtuous cycle of carbons released during various processes are now facing obsolescence because of the depletion of finite fossil fuel reserves and associated environmental pollutions. Thus, the transition into a circular economy in terms of the carbon footprint has been evaluated with the development of efficient microbial cell factories using renewable feedstocks. Herein, the recent progress on bio-based production of organic acids with four-, five-, and six-carbon backbones, including butyric acid and 3-hydroxybutyric acid (C4), 5-aminolevulinic acid and citramalic acid (C5), and hexanoic acid (C6), is discussed. Then, the current research on the production of C4-C6 organic acids is illustrated to suggest future directions for developing crop-residue based consolidated bioprocessing of C4-C6 organic acids using host strains with tailor-made capabilities.
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Affiliation(s)
- Jina Son
- Department of Chemical Engineering and Materials Science, Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul 03760, Republic of Korea
| | - Jeong Chan Joo
- Department of Biotechnology, The Catholic University of Korea, Bucheon-si, Gyeonggi-do 14662, Republic of Korea
| | - Kei-Anne Baritugo
- Department of Chemical Engineering and Materials Science, Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul 03760, Republic of Korea
| | - Seona Jeong
- Department of Chemical Engineering and Materials Science, Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul 03760, Republic of Korea
| | - Ji Yeon Lee
- Department of Chemical Engineering and Materials Science, Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul 03760, Republic of Korea
| | - Hye Jin Lim
- Department of Chemical Engineering and Materials Science, Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul 03760, Republic of Korea
| | - Seo Hyun Lim
- Department of Chemical Engineering and Materials Science, Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul 03760, Republic of Korea
| | - Jee In Yoo
- Department of Chemical Engineering and Materials Science, Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul 03760, Republic of Korea
| | - Si Jae Park
- Department of Chemical Engineering and Materials Science, Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul 03760, Republic of Korea.
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Li Q, Shen T, Dong Y, Liu Y, Nong J, Pan J, Fu B, Xie Q. Clostridium weizhouense sp. nov., an anaerobic bacterium isolated from activated sludge of petroleum wastewater. Int J Syst Evol Microbiol 2022; 72. [DOI: 10.1099/ijsem.0.005330] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A Gram-stain-positive, anaerobic, spore-forming, rod-shaped (0.4–0.6 µm×2.5–3.2 µm), flagellated bacterium, designated strain YB-6T, was isolated from activated sludge of an anaerobic tank at Weizhou marine oil mining wastewater treatment plant in Beihai, Guangxi, PR China. The culture conditions were 25–45 °C (optimum, 37 °C), pH 4–12 (pH 7.0) and NaCl concentration of 0–7 % w/v (0%). Strain YB-6T grew slowly in petroleum wastewater and removed 68.2 % of the total organic carbon in petroleum wastewater within 10 days. Concentrations of naphthalene, anthracene and phenanthrene at an initial concentration of 50 mg l−1 were reduced by 32.8, 40.4 and 14.6 %, respectively, after 7 days. Phylogenetic analysis of the 16S rRNA gene sequence indicated that strain YB-6T belongs to
Clostridium
cluster I and is most closely related to
Clostridium uliginosum
CK55T (98.5 % similarity). The genome size of strain YB-6T was 3.96 Mb, and the G+C content was 26.5 mol%. The average nucleotide identity value between strain YB-6T and
C. uliginosum
CK55T was 81.9 %. The major fatty acids in strain YB-6T were C14 : 0 FAME, C16 : 0 FAME and summed feature 4 (unknown 14.762 and/or C15 : 2 FAME). The main polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, five unidentified aminophospholipids, one unidentified glycolipid and one unidentified aminolipid. Diaminopimelic acid was not detected in the strain YB-6T cell walls. Whole-cell sugars mainly consisted of ribose and galactose. Based on the results of phenotypic and genotypic analyses, strain YB-6T represents a novel species of the genus
Clostridium
, for which the name Clostridium weizhouense sp. nov. is proposed. The type strain is YB-6T (=GDMCC 1.2529T=JCM 34754T).
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Affiliation(s)
- Qing Li
- College of Environmental Science and Engineering, Guilin University of Technology, Guilin 541004, PR China
| | - Taiming Shen
- The Guangxi Key Laboratory of Theory and Technologyfor Environmental Pollution Control, Guilin 541004, PR China
- College of Environmental Science and Engineering, Guilin University of Technology, Guilin 541004, PR China
| | - Yingying Dong
- College of Environmental Science and Engineering, Guilin University of Technology, Guilin 541004, PR China
| | - Yuhui Liu
- College of Environmental Science and Engineering, Guilin University of Technology, Guilin 541004, PR China
| | - Jieliang Nong
- College of Environmental Science and Engineering, Guilin University of Technology, Guilin 541004, PR China
| | - Jiayuan Pan
- College of Environmental Science and Engineering, Guilin University of Technology, Guilin 541004, PR China
| | - Bei Fu
- College of Environmental Science and Engineering, Guilin University of Technology, Guilin 541004, PR China
| | - Qinglin Xie
- College of Environmental Science and Engineering, Guilin University of Technology, Guilin 541004, PR China
- The Guangxi Key Laboratory of Theory and Technologyfor Environmental Pollution Control, Guilin 541004, PR China
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9
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Hao ZK, Li JS, Wang DH, He F, Xue JS, Yin LH, Zheng HB. Efficient production of GlcNAc in an aqueous-organic system with a Chitinolyticbacter meiyuanensis SYBC-H1 mutant. Biotechnol Lett 2022; 44:623-633. [PMID: 35384608 DOI: 10.1007/s10529-022-03248-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2021] [Accepted: 03/16/2022] [Indexed: 11/28/2022]
Abstract
OBJECTIVES Shellfish waste is a primary source for making N-acetyl-D-glucosamine. Thus, establishing a high-efficiency and low-cost bioconversion method to produce N-acetyl-D-glucosamine directly from shellfish waste was promising. RESULTS A mutant C81 was obtained from Chitinolyticbacter meiyuanensis SYBC-H1 via 60Co-γ irradiation. This mutant C81 showed the highest chitinase activity of 9.8 U/mL that was 85% higher than the parent strain. The mutant C81 exhibted improved antioxidant activities, including total antioxidant capacity, superoxide radical ability, and hydroxyl radical scavenging ability, compared to that of the parent strain. Four out of nine organic solvents increased the chitinase activity by 1.9%, 6.8%, 11.7%, and 15.8%, corresponding to methylbenzene, n-heptane, petroleum ether, and n-hexane, respectively. The biphase system composed of aqueous and hexane presented a five-fold reduction of cell viability compared to the control. Using a continuous fermentation bioconversion process, 4.2 g/L GlcNAc was produced from crayfish shell powder with a yield of 80% of the chitin content. CONCLUSIONS This study demonstrated that the mutant C81 is suitable for converting crayfish shell powder into GlcNAc in an aqueous-organic system.
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Affiliation(s)
- Zhi-Kui Hao
- School of Medicine and Pharmaceutical Engineering, Institute of Applied Biotechnology, Taizhou Vocational and Technical College, Taizhou, 318000, China
| | - Jian-Song Li
- School of Medicine and Pharmaceutical Engineering, Institute of Applied Biotechnology, Taizhou Vocational and Technical College, Taizhou, 318000, China
| | - Dan-Hua Wang
- School of Medicine and Pharmaceutical Engineering, Institute of Applied Biotechnology, Taizhou Vocational and Technical College, Taizhou, 318000, China
| | - Fei He
- School of Medicine and Pharmaceutical Engineering, Institute of Applied Biotechnology, Taizhou Vocational and Technical College, Taizhou, 318000, China
| | - Jing-Shi Xue
- Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai, 200234, China
| | - Liang-Hong Yin
- Zhejiang Provincial Key Laboratory of Resources Protection and Innovation of Traditional Chinese Medicine, Zhejiang A&F University, Hangzhou, 311300, China
| | - Hua-Bao Zheng
- College of Environmental and Resources Sciences, Zhejiang A&F University, Hangzhou, 311300, China.
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Mondal S, Santra S, Rakshit S, Kumar Halder S, Hossain M, Chandra Mondal K. Saccharification of lignocellulosic biomass using an enzymatic cocktail of fungal origin and successive production of butanol by Clostridium acetobutylicum. BIORESOURCE TECHNOLOGY 2022; 343:126093. [PMID: 34624476 DOI: 10.1016/j.biortech.2021.126093] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 09/30/2021] [Accepted: 10/02/2021] [Indexed: 06/13/2023]
Abstract
A multistep approach was undertaken for biobutanol production targeting valorization of agricultural waste. Optimum production of lignocellulolytic enzymes [CMCase (3822.93U/mg), FPase (3640.93U/mg), β-glucosidase (3873.92U/mg), xylanase (3460.24U/mg), pectinase (3359.57U/mg), α-amylase (4136.54U/mg), and laccase (3863.16U/mg)] was accomplished through solid-substrate fermentation of pretreated mixed substrates (wheat bran, sugarcane bagasse and orange peel) by Aspergillus niger SKN1 and Trametes hirsuta SKH1. Partially purified enzyme cocktail was employed for saccharification of the said substrate mixture into fermentable sugar (69.23 g/L, product yield of 24% w/w). The recovered sugar with vegetable extract supplements was found as robust fermentable medium that supported 16.51 g/L biobutanol production by Clostridium acetobutylicum ATCC824. The sequential bioprocessing of low-priced substrates and exploitation of vegetable extract as growth factor for microbial butanol production will open a new vista in biofuel research.
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Affiliation(s)
- Subhadeep Mondal
- Center for Life Sciences, Vidyasagar University, Midnapore 721102, West Bengal, India
| | - Sourav Santra
- Department of Microbiology, Vidyasagar University, Midnapore 721102, West Bengal, India
| | - Subham Rakshit
- Department of Microbiology, Vidyasagar University, Midnapore 721102, West Bengal, India
| | - Suman Kumar Halder
- Department of Microbiology, Vidyasagar University, Midnapore 721102, West Bengal, India
| | - Maidul Hossain
- Department of Chemistry, Vidyasagar University, Midnapore 721102, West Bengal, India
| | - Keshab Chandra Mondal
- Department of Microbiology, Vidyasagar University, Midnapore 721102, West Bengal, India.
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11
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Guo H, He T, Lee DJ. Contemporary proteomic research on lignocellulosic enzymes and enzymolysis: A review. BIORESOURCE TECHNOLOGY 2022; 344:126263. [PMID: 34728359 DOI: 10.1016/j.biortech.2021.126263] [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: 10/03/2021] [Revised: 10/26/2021] [Accepted: 10/27/2021] [Indexed: 06/13/2023]
Abstract
This review overviewed the current researches on the isolation of novel strains, the development of novel identification protocols, the key enzymes and their synergistic interactions with other functional enzyme systems, and the strategies for enhancing enzymolysis efficiencies. The main obstacle for realizing biorefinery of lignocellulosic biomass to biofuels or biochemicals is the high cost of enzymolysis stage. Therefore, research prospects to reduce the costs for lignocellulose hydrolysis were outlined.
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Affiliation(s)
- Hongliang Guo
- College of Forestry, Northeast Forestry University, Harbin 150040, China; College of Food Engineering, Harbin University of Commerce, Harbin 150076, China
| | - Tongyuan He
- College of Forestry, Northeast Forestry University, Harbin 150040, China
| | - Duu-Jong Lee
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan; Department of Mechanical Engineering, City University of Hong Kong, Kowloon Tang, Hong Kong.
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12
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Lin L, Zhang Z, Tang H, Guo Y, Zhou B, Liu Y, Huang R, Du L, Pang H. Enhanced sucrose fermentation by introduction of heterologous sucrose transporter and invertase into Clostridium beijerinckii for acetone-butanol-ethanol production. ROYAL SOCIETY OPEN SCIENCE 2021; 8:201858. [PMID: 34567584 PMCID: PMC8456130 DOI: 10.1098/rsos.201858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Accepted: 08/31/2021] [Indexed: 05/12/2023]
Abstract
A heterologous pathway for sucrose transport and metabolism was introduced into Clostridium beijerinckii to improve sucrose use for n-butanol production. The combined expression of StSUT1, encoding a sucrose transporter from potato (Solanum tuberosum), and SUC2, encoding a sucrose invertase from Saccharomyces cerevisiae, remarkably enhanced n-butanol production. With sucrose, sugarcane molasses and sugarcane juice as substrates, the C. beijerinckii strain harbouring StSUT1 and SUC2 increased acetone-butanol-ethanol production by 38.7%, 22.3% and 52.8%, respectively, compared with the wild-type strain. This is the first report to demonstrate enhanced sucrose fermentation due to the heterologous expression of a sucrose transporter and invertase in Clostridium. The metabolic engineering strategy used in this study can be widely applied in other microorganisms to enhance the production of high-value compounds from sucrose-based biomass.
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Affiliation(s)
- Lihua Lin
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi Research Center for Microbial and Enzymatic Technology, College of Life Science and Technology, Guangxi University, Daxue Road No. 100, Nanning, Guangxi 530005, People's Republic of China
- Guangxi Key Laboratory of Bio-refinery, National Engineering Research Center for Non-Food Biorefinery, State Key Laboratory of Non-Food Biomass and Enzyme Technology, Guangxi Academy of Sciences, Daling Road No. 98, Nanning, Guangxi 530007, People's Republic of China
| | - Zhikai Zhang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi Research Center for Microbial and Enzymatic Technology, College of Life Science and Technology, Guangxi University, Daxue Road No. 100, Nanning, Guangxi 530005, People's Republic of China
| | - Hongchi Tang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi Research Center for Microbial and Enzymatic Technology, College of Life Science and Technology, Guangxi University, Daxue Road No. 100, Nanning, Guangxi 530005, People's Republic of China
- Guangxi Key Laboratory of Bio-refinery, National Engineering Research Center for Non-Food Biorefinery, State Key Laboratory of Non-Food Biomass and Enzyme Technology, Guangxi Academy of Sciences, Daling Road No. 98, Nanning, Guangxi 530007, People's Republic of China
| | - Yuan Guo
- Guangxi Key Laboratory of Bio-refinery, National Engineering Research Center for Non-Food Biorefinery, State Key Laboratory of Non-Food Biomass and Enzyme Technology, Guangxi Academy of Sciences, Daling Road No. 98, Nanning, Guangxi 530007, People's Republic of China
| | - Bingqing Zhou
- Guangxi Key Laboratory of Bio-refinery, National Engineering Research Center for Non-Food Biorefinery, State Key Laboratory of Non-Food Biomass and Enzyme Technology, Guangxi Academy of Sciences, Daling Road No. 98, Nanning, Guangxi 530007, People's Republic of China
| | - Yi Liu
- Guangxi Key Laboratory of Bio-refinery, National Engineering Research Center for Non-Food Biorefinery, State Key Laboratory of Non-Food Biomass and Enzyme Technology, Guangxi Academy of Sciences, Daling Road No. 98, Nanning, Guangxi 530007, People's Republic of China
| | - Ribo Huang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi Research Center for Microbial and Enzymatic Technology, College of Life Science and Technology, Guangxi University, Daxue Road No. 100, Nanning, Guangxi 530005, People's Republic of China
| | - Liqin Du
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi Research Center for Microbial and Enzymatic Technology, College of Life Science and Technology, Guangxi University, Daxue Road No. 100, Nanning, Guangxi 530005, People's Republic of China
| | - Hao Pang
- Guangxi Key Laboratory of Bio-refinery, National Engineering Research Center for Non-Food Biorefinery, State Key Laboratory of Non-Food Biomass and Enzyme Technology, Guangxi Academy of Sciences, Daling Road No. 98, Nanning, Guangxi 530007, People's Republic of China
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13
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Bai SK, Hong Y, Wu YR. Emerging technologies for genetic modification of solventogenic clostridia: From tool to strategy development. BIORESOURCE TECHNOLOGY 2021; 334:125222. [PMID: 33951568 DOI: 10.1016/j.biortech.2021.125222] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 04/20/2021] [Accepted: 04/21/2021] [Indexed: 06/12/2023]
Abstract
Solventogenic clostridia has been considered as one of the most potential microbial cell factories for biofuel production in the biorefinery industry. However, the inherent shortcomings of clostridia strains such as low productivity, by-products formation and toxic tolerance still strongly restrict the large-scale application. Therefore, concerns regarding the genetic modification of solventogenic clostridia have spurred interests into the development of modern gene-editing tools. In this review, we summarize the latest advances of genetic tools involved in modifying solventogenic clostridia. Following a systematic comparison on their respective characteristics, we then review the corresponding strategies for overcoming the obstacles to the enhanced production. Discussing the progress of other microbial cell factories for solventogenesis, we finally describe the key challenges and trends with valuable recommendations for future large-scale biosolvent industrial application.
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Affiliation(s)
- Sheng-Kai Bai
- Department of Biology, Shantou University, Shantou, Guangdong 515063, China
| | - Ying Hong
- Department of Biology, Shantou University, Shantou, Guangdong 515063, China
| | - Yi-Rui Wu
- Department of Biology, Shantou University, Shantou, Guangdong 515063, China; Guangdong Provincial Key Laboratory of Marine Biotechnology, Shantou University, Shantou, Guangdong 515063, China; Institute of Marine Sciences, Shantou University, Shantou, Guangdong 515063, China.
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14
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Wu M, Jiang Y, Liu Y, Mou L, Zhang W, Xin F, Jiang M. Microbial application of thermophilic Thermoanaerobacterium species in lignocellulosic biorefinery. Appl Microbiol Biotechnol 2021; 105:5739-5749. [PMID: 34283269 DOI: 10.1007/s00253-021-11450-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 07/04/2021] [Accepted: 07/06/2021] [Indexed: 12/13/2022]
Abstract
Recently, thermophilic Thermoanaerobacterium species have attracted increasing attentions in consolidated bioprocessing (CBP), which can directly utilize lignocellulosic materials for biofuels production. Compared to the mesophilic process, thermophilic process shows greater prospects in CBP due to its relatively highly efficiency of lignocellulose degradation. In addition, thermophilic conditions can avoid microbial contamination, reduce the cooling costs, and further facilitate the downstream product recovery. However, only few reviews specifically focused on the microbial applications of thermophilic Thermoanaerobacterium species in lignocellulosic biorefinery. Accordingly, this review will comprehensively summarize the recent advances of Thermoanaerobacterium species in lignocellulosic biorefinery, including their secreted xylanases and bioenergy production. Furthermore, the co-culture can significantly reduce the metabolic burden and achieve the more complex work, which will be discussed as the further perspectives. KEY POINTS: • Thermoanaerobacterium species, promising chassis for lignocellulosic biorefinery. • Potential capability of hemicellulose degradation for Thermoanaerobacterium species. • Efficient bioenergy production by Thermoanaerobacterium species through metabolic engineering.
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Affiliation(s)
- Mengdi Wu
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering Nanjing Tech University, Puzhu South Road 30#, Nanjing, 211800, People's Republic of China
| | - Yujia Jiang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering Nanjing Tech University, Puzhu South Road 30#, Nanjing, 211800, People's Republic of China
| | - Yansong Liu
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering Nanjing Tech University, Puzhu South Road 30#, Nanjing, 211800, People's Republic of China
| | - Lu Mou
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering Nanjing Tech University, Puzhu South Road 30#, Nanjing, 211800, People's Republic of China
| | - Wenming Zhang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering Nanjing Tech University, Puzhu South Road 30#, Nanjing, 211800, People's Republic of China.
- Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing, 211800, People's Republic of China.
| | - Fengxue Xin
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering Nanjing Tech University, Puzhu South Road 30#, Nanjing, 211800, People's Republic of China.
- Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing, 211800, People's Republic of China.
| | - Min Jiang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering Nanjing Tech University, Puzhu South Road 30#, Nanjing, 211800, People's Republic of China
- Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing, 211800, People's Republic of China
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15
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Bao T, Hou W, Wu X, Lu L, Zhang X, Yang ST. Engineering Clostridium cellulovorans for highly selective n-butanol production from cellulose in consolidated bioprocessing. Biotechnol Bioeng 2021; 118:2703-2718. [PMID: 33844271 DOI: 10.1002/bit.27789] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 03/06/2021] [Accepted: 04/09/2021] [Indexed: 01/05/2023]
Abstract
Cellulosic n-butanol from renewable lignocellulosic biomass has gained increased interest. Previously, we have engineered Clostridium cellulovorans, a cellulolytic acidogen, to overexpress the bifunctional butyraldehyde/butanol dehydrogenase gene adhE2 from C. acetobutylicum for n-butanol production from crystalline cellulose. However, butanol production by this engineered strain had a relatively low yield of approximately 0.22 g/g cellulose due to the coproduction of ethanol and acids. We hypothesized that strengthening the carbon flux through the central butyryl-CoA biosynthesis pathway and increasing intracellular NADH availability in C. cellulovorans adhE2 would enhance n-butanol production. In this study, thiolase (thlACA ) from C. acetobutylicum and 3-hydroxybutyryl-CoA dehydrogenase (hbdCT ) from C. tyrobutyricum were overexpressed in C. cellulovorans adhE2 to increase the flux from acetyl-CoA to butyryl-CoA. In addition, ferredoxin-NAD(P)+ oxidoreductase (fnr), which can regenerate the intracellular NAD(P)H and thus increase butanol biosynthesis, was also overexpressed. Metabolic flux analyses showed that mutants overexpressing these genes had a significantly increased carbon flux toward butyryl-CoA, which resulted in increased production of butyrate and butanol. The addition of methyl viologen as an electron carrier in batch fermentation further directed more carbon flux towards n-butanol biosynthesis due to increased reducing equivalent or NADH. The engineered strain C. cellulovorans adhE2-fnrCA -thlACA -hbdCT produced n-butanol from cellulose at a 50% higher yield (0.34 g/g), the highest ever obtained in batch fermentation by any known bacterial strain. The engineered C. cellulovorans is thus a promising host for n-butanol production from cellulosic biomass in consolidated bioprocessing.
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Affiliation(s)
- Teng Bao
- William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, Ohio, USA
| | - Wenjie Hou
- William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, Ohio, USA.,College of Life Sciences, Northwest A&F University, Yangling, Shanxi, China
| | - Xuefeng Wu
- William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, Ohio, USA.,School of Food and Biological Engineering, Hefei University of Technology, Hefei, China
| | - Li Lu
- William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, Ohio, USA
| | - Xian Zhang
- William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, Ohio, USA.,School of Biotechnology, Jiangnan University, Wuxi, China
| | - Shang-Tian Yang
- William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, Ohio, USA
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16
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Influence of Culture Conditions on the Bioreduction of Organic Acids to Alcohols by Thermoanaerobacter pseudoethanolicus. Microorganisms 2021; 9:microorganisms9010162. [PMID: 33445711 PMCID: PMC7828175 DOI: 10.3390/microorganisms9010162] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 12/24/2020] [Accepted: 01/08/2021] [Indexed: 11/17/2022] Open
Abstract
Thermoanaerobacter species have recently been observed to reduce carboxylic acids to their corresponding alcohols. The present investigation shows that Thermoanaerobacter pseudoethanolicus converts C2-C6 short-chain fatty acids (SCFAs) to their corresponding alcohols in the presence of glucose. The conversion yields varied from 21% of 3-methyl-1-butyrate to 57.9% of 1-pentanoate being converted to their corresponding alcohols. Slightly acidic culture conditions (pH 6.5) was optimal for the reduction. By increasing the initial glucose concentration, an increase in the conversion of SCFAs reduced to their corresponding alcohols was observed. Inhibitory experiments on C2-C8 alcohols showed that C4 and higher alcohols are inhibitory to T. pseudoethanolicus suggesting that other culture modes may be necessary to improve the amount of fatty acids reduced to the analogous alcohol. The reduction of SCFAs to their corresponding alcohols was further demonstrated using 13C-labelled fatty acids and the conversion was followed kinetically. Finally, increased activity of alcohol dehydrogenase (ADH) and aldehyde oxidation activity was observed in cultures of T. pseudoethanolicus grown on glucose as compared to glucose supplemented with either 3-methyl-1-butyrate or pentanoate, using both NADH and NADPH as cofactors, although the presence of the latter showed higher ADH and aldehyde oxidoreductase (ALDH) activity.
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17
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Cui Y, Yang KL, Zhou K. Using Co-Culture to Functionalize Clostridium Fermentation. Trends Biotechnol 2020; 39:914-926. [PMID: 33342558 DOI: 10.1016/j.tibtech.2020.11.016] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2020] [Revised: 11/22/2020] [Accepted: 11/25/2020] [Indexed: 01/23/2023]
Abstract
Clostridium fermentations have been developed for producing butanol and other value-added chemicals, but their development is constrained by some limitations, such as relatively high substrate cost and the need to maintain an anaerobic condition. Recently, co-culture is emerging as a popular way to address these limitations by introducing a partner strain with Clostridium. Generally speaking, the co-culture strategy enables the use of a cheaper substrate, maintains the growth of Clostridium without any anaerobic treatment, improves product yields, and/or widens the product spectrum. Herein, we review recent developments of co-culture strategies involving Clostridium species according to their partner stains' functions with representative examples. We also discuss research challenges that need to be addressed for the future development of Clostridium co-cultures.
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Affiliation(s)
- Yonghao Cui
- Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore, 117585, Singapore
| | - Kun-Lin Yang
- Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore, 117585, Singapore.
| | - Kang Zhou
- Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore, 117585, Singapore.
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18
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How to outwit nature: Omics insight into butanol tolerance. Biotechnol Adv 2020; 46:107658. [PMID: 33220435 DOI: 10.1016/j.biotechadv.2020.107658] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 11/10/2020] [Accepted: 11/13/2020] [Indexed: 12/16/2022]
Abstract
The energy crisis, depletion of oil reserves, and global climate changes are pressing problems of developed societies. One possibility to counteract that is microbial production of butanol, a promising new fuel and alternative to many petrochemical reagents. However, the high butanol toxicity to all known microbial species is the main obstacle to its industrial implementation. The present state of the art review aims to expound the recent advances in modern omics approaches to resolving this insurmountable to date problem of low butanol tolerance. Genomics, transcriptomics, and proteomics show that butanol tolerance is a complex phenomenon affecting multiple genes and their expression. Efflux pumps, stress and multidrug response, membrane transport, and redox-related genes are indicated as being most important during butanol challenge, in addition to fine-tuning of global regulators of transcription (Spo0A, GntR), which may further improve tolerance. Lipidomics shows that the alterations in membrane composition (saturated lipids and plasmalogen increase) are very much species-specific and butanol-related. Glycomics discloses the pleiotropic effect of CcpA, the role of alternative sugar transport, and the production of exopolysaccharides as alternative routes to overcoming butanol stress. Unfortunately, the strain that simultaneously syntheses and tolerates butanol in concentrations that allow its commercialization has not yet been discovered or produced. Omics insight will allow the purposeful increase of butanol tolerance in natural and engineered producers and the effective heterologous expression of synthetic butanol pathways in strains hereditary butanol-resistant up to 3.2 - 4.9% (w/v). Future breakthrough can be achieved by a detailed study of the membrane proteome, of which 21% are proteins with unknown functions.
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19
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Li X, Zhao X, Yang J, Li S, Bai S, Zhao X. Recognition of core microbial communities contributing to complex organic components degradation during dry anaerobic digestion of chicken manure. BIORESOURCE TECHNOLOGY 2020; 314:123765. [PMID: 32652447 DOI: 10.1016/j.biortech.2020.123765] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 06/23/2020] [Accepted: 06/26/2020] [Indexed: 06/11/2023]
Abstract
Microbial metabolism of complex organic components can drive different microbial communities, which is significant to the process of dry anaerobic digestion (AD). However, possible mechanisms between organic components and the corresponding microbial communities during the process of dry AD is poorly investigated. Results showed that the microbial species affecting the degradation of organic components were 69 nodes (13.3%) in the hydrolysis stage, hemicellulose was mainly degraded by Methanobacterium (2.3%), with a degradation rate of 35.0%. In the acetogenesis stage, the microbial species were 27 nodes (10.3%), hemicellulose was mainly degraded by LK-44f (0.1%) and Treponema (0.3%), with a degradation rate of 52.2%. In the methanogenesis stage, the microbial species were 10 nodes (4.8%), polysaccharide was mainly degraded by Ureibacillus (0.1%), with a degradation rate of 46.9%. The study provides theoretical support for the rapid degradation of complex components by segment-oriented regulation.
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Affiliation(s)
- Xiang Li
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; Innovation Base of Groundwater & Environmental System Engineering, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Xiuyun Zhao
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; Innovation Base of Groundwater & Environmental System Engineering, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Jinjin Yang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; Innovation Base of Groundwater & Environmental System Engineering, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Shaokang Li
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; Innovation Base of Groundwater & Environmental System Engineering, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Sicong Bai
- College of Life Science, Northeast Agricultural University, Harbin 150030, China
| | - Xinyu Zhao
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; Innovation Base of Groundwater & Environmental System Engineering, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
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20
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Jiang Y, Dong W, Xin F, Jiang M. Designing Synthetic Microbial Consortia for Biofuel Production. Trends Biotechnol 2020; 38:828-831. [DOI: 10.1016/j.tibtech.2020.02.002] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 01/31/2020] [Accepted: 02/03/2020] [Indexed: 11/25/2022]
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21
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Jiang Y, Lv Y, Wu R, Lu J, Dong W, Zhou J, Zhang W, Xin F, Jiang M. Consolidated bioprocessing performance of a two‐species microbial consortium for butanol production from lignocellulosic biomass. Biotechnol Bioeng 2020; 117:2985-2995. [DOI: 10.1002/bit.27464] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Revised: 05/11/2020] [Accepted: 06/15/2020] [Indexed: 12/12/2022]
Affiliation(s)
- Yujia Jiang
- State Key Laboratory of Materials‐Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering Nanjing Tech University Nanjing China
| | - Yang Lv
- State Key Laboratory of Materials‐Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering Nanjing Tech University Nanjing China
| | - Ruofan Wu
- State Key Laboratory of Materials‐Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering Nanjing Tech University Nanjing China
| | - Jiasheng Lu
- State Key Laboratory of Materials‐Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering Nanjing Tech University Nanjing China
| | - Weiliang Dong
- State Key Laboratory of Materials‐Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering Nanjing Tech University Nanjing China
- Jiangsu National Synergetic Innovation Center for Advanced Materials Nanjing Tech University Nanjing China
| | - Jie Zhou
- State Key Laboratory of Materials‐Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering Nanjing Tech University Nanjing China
| | - Wenming Zhang
- State Key Laboratory of Materials‐Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering Nanjing Tech University Nanjing China
- Jiangsu National Synergetic Innovation Center for Advanced Materials Nanjing Tech University Nanjing China
| | - Fengxue Xin
- State Key Laboratory of Materials‐Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering Nanjing Tech University Nanjing China
- Jiangsu National Synergetic Innovation Center for Advanced Materials Nanjing Tech University Nanjing China
| | - Min Jiang
- State Key Laboratory of Materials‐Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering Nanjing Tech University Nanjing China
- Jiangsu National Synergetic Innovation Center for Advanced Materials Nanjing Tech University Nanjing China
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22
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Zhu D, Adebisi WA, Ahmad F, Sethupathy S, Danso B, Sun J. Recent Development of Extremophilic Bacteria and Their Application in Biorefinery. Front Bioeng Biotechnol 2020; 8:483. [PMID: 32596215 PMCID: PMC7303364 DOI: 10.3389/fbioe.2020.00483] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Accepted: 04/27/2020] [Indexed: 12/22/2022] Open
Abstract
The biorefining technology for biofuels and chemicals from lignocellulosic biomass has made great progress in the world. However, mobilization of laboratory research toward industrial setup needs to meet a series of criteria, including the selection of appropriate pretreatment technology, breakthrough in enzyme screening, pathway optimization, and production technology, etc. Extremophiles play an important role in biorefinery by providing novel metabolic pathways and catalytically stable/robust enzymes that are able to act as biocatalysts under harsh industrial conditions on their own. This review summarizes the potential application of thermophilic, psychrophilic alkaliphilic, acidophilic, and halophilic bacteria and extremozymes in the pretreatment, saccharification, fermentation, and lignin valorization process. Besides, the latest studies on the engineering bacteria of extremophiles using metabolic engineering and synthetic biology technologies for high-efficiency biofuel production are also introduced. Furthermore, this review explores the comprehensive application potential of extremophiles and extremozymes in biorefinery, which is partly due to their specificity and efficiency, and points out the necessity of accelerating the commercialization of extremozymes.
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Affiliation(s)
- Daochen Zhu
- Biofuels Institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, China
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Open Laboratory of Applied Microbiology, Guangdong Institute of Microbiology, Guangzhou, China
| | - Wasiu Adewale Adebisi
- Biofuels Institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, China
| | - Fiaz Ahmad
- Biofuels Institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, China
| | - Sivasamy Sethupathy
- Biofuels Institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, China
| | - Blessing Danso
- Biofuels Institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, China
| | - Jianzhong Sun
- Biofuels Institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, China
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Li S, Huang L, Ke C, Pang Z, Liu L. Pathway dissection, regulation, engineering and application: lessons learned from biobutanol production by solventogenic clostridia. BIOTECHNOLOGY FOR BIOFUELS 2020; 13:39. [PMID: 32165923 PMCID: PMC7060580 DOI: 10.1186/s13068-020-01674-3] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Accepted: 02/04/2020] [Indexed: 06/01/2023]
Abstract
The global energy crisis and limited supply of petroleum fuels have rekindled the interest in utilizing a sustainable biomass to produce biofuel. Butanol, an advanced biofuel, is a superior renewable resource as it has a high energy content and is less hygroscopic than other candidates. At present, the biobutanol route, employing acetone-butanol-ethanol (ABE) fermentation in Clostridium species, is not economically competitive due to the high cost of feedstocks, low butanol titer, and product inhibition. Based on an analysis of the physiological characteristics of solventogenic clostridia, current advances that enhance ABE fermentation from strain improvement to product separation were systematically reviewed, focusing on: (1) elucidating the metabolic pathway and regulation mechanism of butanol synthesis; (2) enhancing cellular performance and robustness through metabolic engineering, and (3) optimizing the process of ABE fermentation. Finally, perspectives on engineering and exploiting clostridia as cell factories to efficiently produce various chemicals and materials are also discussed.
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Affiliation(s)
- Shubo Li
- College of Light Industry and Food Engineering, Guangxi University, Nanning, 530004 China
| | - Li Huang
- College of Light Industry and Food Engineering, Guangxi University, Nanning, 530004 China
| | - Chengzhu Ke
- College of Light Industry and Food Engineering, Guangxi University, Nanning, 530004 China
| | - Zongwen Pang
- College of Life Science and Technology, Guangxi University, Nanning, 530005 China
| | - Liming Liu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122 China
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Wen Z, Li Q, Liu J, Jin M, Yang S. Consolidated bioprocessing for butanol production of cellulolytic Clostridia: development and optimization. Microb Biotechnol 2020; 13:410-422. [PMID: 31448546 PMCID: PMC7017829 DOI: 10.1111/1751-7915.13478] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 08/02/2019] [Accepted: 08/04/2019] [Indexed: 12/20/2022] Open
Abstract
Butanol is an important bulk chemical, as well as a promising renewable gasoline substitute, that is commonly produced by solventogenic Clostridia. The main cost of cellulosic butanol fermentation is caused by cellulases that are required to saccharify lignocellulose, since solventogenic Clostridia cannot efficiently secrete cellulases. However, cellulolytic Clostridia can natively degrade lignocellulose and produce ethanol, acetate, butyrate and even butanol. Therefore, cellulolytic Clostridia offer an alternative to develop consolidated bioprocessing (CBP), which combines cellulase production, lignocellulose hydrolysis and co-fermentation of hexose/pentose into butanol in one step. This review focuses on CBP advances for butanol production of cellulolytic Clostridia and various synthetic biotechnologies that drive these advances. Moreover, the efforts to optimize the CBP-enabling cellulolytic Clostridia chassis are also discussed. These include the development of genetic tools, pentose metabolic engineering and the improvement of butanol tolerance. Designer cellulolytic Clostridia or consortium provide a promising approach and resource to accelerate future CBP for butanol production.
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Affiliation(s)
- Zhiqiang Wen
- School of Environmental and Biological EngineeringNanjing University of Science and TechnologyNanjing210094China
| | - Qi Li
- College of Life SciencesSichuan Normal UniversityLongquan, Chengdu610101China
| | - Jinle Liu
- Key Laboratory of Synthetic BiologyCAS Center for Excellence in Molecular Plant SciencesShanghai Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghai200032China
| | - Mingjie Jin
- School of Environmental and Biological EngineeringNanjing University of Science and TechnologyNanjing210094China
| | - Sheng Yang
- Key Laboratory of Synthetic BiologyCAS Center for Excellence in Molecular Plant SciencesShanghai Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghai200032China
- Huzhou Center of Industrial BiotechnologyShanghai Institutes of Biological SciencesChinese Academy of SciencesShanghai200032China
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Sun X, Atiyeh HK, Adesanya Y, Okonkwo C, Zhang H, Huhnke RL, Ezeji T. Feasibility of using biochar as buffer and mineral nutrients replacement for acetone-butanol-ethanol production from non-detoxified switchgrass hydrolysate. BIORESOURCE TECHNOLOGY 2020; 298:122569. [PMID: 31862676 DOI: 10.1016/j.biortech.2019.122569] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Revised: 12/03/2019] [Accepted: 12/04/2019] [Indexed: 05/22/2023]
Abstract
Biochar can be an inexpensive pH buffer and source of mineral and trace metal nutrients in acetone-butanol-ethanol (ABE) fermentation. This study evaluated the feasibility of replacing expensive 4-morpholineethanesulfonic acid (MES) P2 buffer and mineral nutrients with biochar made from switchgrass (SGBC), forage sorghum (FSBC), redcedar (RCBC) and poultry litter (PLBC) for ABE fermentation. Fermentations using Clostridium beijerinckii ATCC 51743 in glucose and non-detoxified switchgrass hydrolysate media were performed at 35 °C in 250 mL bottles for 72 h. Medium containing buffer and minerals without biochar was the control. Similar ABE production (about 18.0 g/L) in glucose media with SGBC, FSBC and RCBC and control was measured. However in non-detoxified switchgrass hydrolysate medium, SGBC, RCBC and PLBC produced more ABE (about 18.5 g/L) than the control (10.1 g/L). This demonstrates that biochar is an effective buffer and mineral supplement for ABE production from lignocellulosic biomass without costly detoxification process.
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Affiliation(s)
- Xiao Sun
- Biosystems and Agricultural Engineering, Oklahoma State University, Stillwater, OK, USA
| | - Hasan K Atiyeh
- Biosystems and Agricultural Engineering, Oklahoma State University, Stillwater, OK, USA.
| | - Yinka Adesanya
- Biosystems and Agricultural Engineering, Oklahoma State University, Stillwater, OK, USA
| | - Christopher Okonkwo
- Department of Animal Science, The Ohio State University, and Ohio State Agricultural Research and Development Center, Wooster, OH, USA
| | - Hailin Zhang
- Department of Plant and Soil Sciences, Oklahoma State University, Stillwater, OK, USA
| | - Raymond L Huhnke
- Biosystems and Agricultural Engineering, Oklahoma State University, Stillwater, OK, USA
| | - Thaddeus Ezeji
- Department of Animal Science, The Ohio State University, and Ohio State Agricultural Research and Development Center, Wooster, OH, USA
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Mamo G, Mattiasson B. Alkaliphiles: The Versatile Tools in Biotechnology. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2020; 172:1-51. [PMID: 32342125 DOI: 10.1007/10_2020_126] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The extreme environments within the biosphere are inhabited by organisms known as extremophiles. Lately, these organisms are attracting a great deal of interest from researchers and industrialists. The motive behind this attraction is mainly related to the desire for new and efficient products of biotechnological importance and human curiosity of understanding nature. Organisms living in common "human-friendly" environments have served humanity for a very long time, and this has led to exhaustion of the low-hanging "fruits," a phenomenon witnessed by the diminishing rate of new discoveries. For example, acquiring novel products such as drugs from the traditional sources has become difficult and expensive. Such challenges together with the basic research interest have brought the exploration of previously neglected or unknown groups of organisms. Extremophiles are among these groups which have been brought to focus and garnering a growing importance in biotechnology. In the last few decades, numerous extremophiles and their products have got their ways into industrial, agricultural, environmental, pharmaceutical, and other biotechnological applications.Alkaliphiles, organisms which thrive optimally at or above pH 9, are one of the most important classes of extremophiles. To flourish in their extreme habitats, alkaliphiles evolved impressive structural and functional adaptations. The high pH adaptation gave unique biocatalysts that are operationally stable at elevated pH and several other novel products with immense biotechnological application potential. Advances in the cultivation techniques, success in gene cloning and expression, metabolic engineering, metagenomics, and other related techniques are significantly contributing to expand the application horizon of these remarkable organisms of the 'bizarre' world. Studies have shown the enormous potential of alkaliphiles in numerous biotechnological applications. Although it seems just the beginning, some fantastic strides are already made in tapping this potential. This work tries to review some of the prominent applications of alkaliphiles by focusing such as on their enzymes, metabolites, exopolysaccharides, and biosurfactants. Moreover, the chapter strives to assesses the whole-cell applications of alkaliphiles including in biomining, food and feed supplementation, bioconstruction, microbial fuel cell, biofuel production, and bioremediation.
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Affiliation(s)
| | - Bo Mattiasson
- Department of Biotechnology, Lund University, Lund, Sweden
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28
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Villena GK, Kitazono AA, Hernández-Macedo M L. Bioengineering Fungi and Yeast for the Production of Enzymes, Metabolites, and Value-Added Compounds. Fungal Biol 2020. [DOI: 10.1007/978-3-030-41870-0_9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Liu L, Yang J, Yang Y, Luo L, Wang R, Zhang Y, Yuan H. Consolidated bioprocessing performance of bacterial consortium EMSD5 on hemicellulose for isopropanol production. BIORESOURCE TECHNOLOGY 2019; 292:121965. [PMID: 31415990 DOI: 10.1016/j.biortech.2019.121965] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 08/04/2019] [Accepted: 08/05/2019] [Indexed: 06/10/2023]
Abstract
Consolidated bioprocessing (CBP) of lignocellulose by bacterial consortium for isopropanol production is considered as the most promising strategy. However, low utilization of xylan caused by the complex sidechain structure remains inhibit the conversion of full-biomass. In this study, isopropanol production from different lignocelluloses by the consortium EMSD5 through CBP was performed. A total of 7.00 g/L of isopropanol was obtained from corncob by optimizing fermentation conditions. Isopropanol production by EMSD5 was mainly based on utilizing xylan in corncob and isopropanol titer was increased by 47.71% and reached up to 8.39 g/L using arabinoxylan compared with linear xylan. The analysis of community structures and the isolation of key strain confirmed the enrichment of the isopropanol producer, Clostridium beijierinckii, in the bacterial community when it was incubated with corn glucuronoarabinoxylan and the cooperation between C. beijerinckii and lignocellulose degraders. The unique features of EMSD5 could lead to large-scale isopropanol production using lignocellulose.
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Affiliation(s)
- Liang Liu
- State Key Laboratory of Agrobiotechnology and Key Laboratory of Soil Microbiology, Ministry of Agriculture, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Jinshui Yang
- State Key Laboratory of Agrobiotechnology and Key Laboratory of Soil Microbiology, Ministry of Agriculture, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Yi Yang
- State Key Laboratory of Agrobiotechnology and Key Laboratory of Soil Microbiology, Ministry of Agriculture, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Lijin Luo
- Fujian Institute of Microbiology, Fuzhou 350007, China
| | - Ruonan Wang
- State Key Laboratory of Agrobiotechnology and Key Laboratory of Soil Microbiology, Ministry of Agriculture, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Yu Zhang
- State Key Laboratory of Agrobiotechnology and Key Laboratory of Soil Microbiology, Ministry of Agriculture, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Hongli Yuan
- State Key Laboratory of Agrobiotechnology and Key Laboratory of Soil Microbiology, Ministry of Agriculture, College of Biological Sciences, China Agricultural University, Beijing 100193, China.
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Jiang Y, Lv Y, Wu R, Sui Y, Chen C, Xin F, Zhou J, Dong W, Jiang M. Current status and perspectives on biobutanol production using lignocellulosic feedstocks. ACTA ACUST UNITED AC 2019. [DOI: 10.1016/j.biteb.2019.100245] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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31
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Birgen C, Dürre P, Preisig HA, Wentzel A. Butanol production from lignocellulosic biomass: revisiting fermentation performance indicators with exploratory data analysis. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:167. [PMID: 31297155 PMCID: PMC6598312 DOI: 10.1186/s13068-019-1508-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Accepted: 06/19/2019] [Indexed: 05/09/2023]
Abstract
After just more than 100 years of history of industrial acetone-butanol-ethanol (ABE) fermentation, patented by Weizmann in the UK in 1915, butanol is again today considered a promising biofuel alternative based on several advantages compared to the more established biofuels ethanol and methanol. Large-scale fermentative production of butanol, however, still suffers from high substrate cost and low product titers and selectivity. There have been great advances the last decades to tackle these problems. However, understanding the fermentation process variables and their interconnectedness with a holistic view of the current scientific state-of-the-art is lacking to a great extent. To illustrate the benefits of such a comprehensive approach, we have developed a dataset by collecting data from 175 fermentations of lignocellulosic biomass and mixed sugars to produce butanol that reported during the past three decades of scientific literature and performed an exploratory data analysis to map current trends and bottlenecks. This review presents the results of this exploratory data analysis as well as main features of fermentative butanol production from lignocellulosic biomass with a focus on performance indicators as a useful tool to guide further research and development in the field towards more profitable butanol manufacturing for biofuel applications in the future.
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Affiliation(s)
- Cansu Birgen
- Department of Chemical Engineering, NTNU, 7491 Trondheim, Norway
| | - Peter Dürre
- Institute of Microbiology and Biotechnology, Ulm University, 89069 Ulm, Germany
| | - Heinz A. Preisig
- Department of Chemical Engineering, NTNU, 7491 Trondheim, Norway
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Jiang Y, Wu R, Zhou J, He A, Xu J, Xin F, Zhang W, Ma J, Jiang M, Dong W. Recent advances of biofuels and biochemicals production from sustainable resources using co-cultivation systems. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:155. [PMID: 31285755 PMCID: PMC6588928 DOI: 10.1186/s13068-019-1495-7] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Accepted: 06/11/2019] [Indexed: 05/09/2023]
Abstract
Microbial communities are ubiquitous in nature and exhibit several attractive features, such as sophisticated metabolic capabilities and strong environment robustness. Inspired by the advantages of natural microbial consortia, diverse artificial co-cultivation systems have been metabolically constructed for biofuels, chemicals and natural products production. In these co-cultivation systems, especially genetic engineering ones can reduce the metabolic burden caused by the complex of metabolic pathway through labor division, and improve the target product production significantly. This review summarized the most up-to-dated co-cultivation systems used for biofuels, chemicals and nature products production. In addition, major challenges associated with co-cultivation systems are also presented and discussed for meeting further industrial demands.
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Affiliation(s)
- Yujia Jiang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Puzhu South Road 30#, Nanjing, 211800 People’s Republic of China
| | - Ruofan Wu
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Puzhu South Road 30#, Nanjing, 211800 People’s Republic of China
| | - Jie Zhou
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Puzhu South Road 30#, Nanjing, 211800 People’s Republic of China
- Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing, 211800 People’s Republic of China
| | - Aiyong He
- Jiangsu Key Laboratory for Biomass-based Energy and Enzyme Technology, Huaiyin Normal University, Huaian, 223300 People’s Republic of China
| | - Jiaxing Xu
- Jiangsu Key Laboratory for Biomass-based Energy and Enzyme Technology, Huaiyin Normal University, Huaian, 223300 People’s Republic of China
| | - Fengxue Xin
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Puzhu South Road 30#, Nanjing, 211800 People’s Republic of China
- Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing, 211800 People’s Republic of China
| | - Wenming Zhang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Puzhu South Road 30#, Nanjing, 211800 People’s Republic of China
- Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing, 211800 People’s Republic of China
| | - Jiangfeng Ma
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Puzhu South Road 30#, Nanjing, 211800 People’s Republic of China
- Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing, 211800 People’s Republic of China
| | - Min Jiang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Puzhu South Road 30#, Nanjing, 211800 People’s Republic of China
- Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing, 211800 People’s Republic of China
| | - Weiliang Dong
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Puzhu South Road 30#, Nanjing, 211800 People’s Republic of China
- Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing, 211800 People’s Republic of China
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de Paula RG, Antoniêto ACC, Ribeiro LFC, Srivastava N, O'Donovan A, Mishra PK, Gupta VK, Silva RN. Engineered microbial host selection for value-added bioproducts from lignocellulose. Biotechnol Adv 2019; 37:107347. [PMID: 30771467 DOI: 10.1016/j.biotechadv.2019.02.003] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2018] [Revised: 01/27/2019] [Accepted: 02/08/2019] [Indexed: 12/12/2022]
Abstract
Lignocellulose is a rich and sustainable globally available carbon source and is considered a prominent alternative raw material for producing biofuels and valuable chemical compounds. Enzymatic hydrolysis is one of the crucial steps of lignocellulose degradation. Cellulolytic and hemicellulolytic enzyme mixes produced by different microorganisms including filamentous fungi, yeasts and bacteria, are used to degrade the biomass to liberate monosaccharides and other compounds for fermentation or conversion to value-added products. During biomass pretreatment and degradation, toxic compounds are produced, and undesirable carbon catabolic repression (CCR) can occur. In order to solve this problem, microbial metabolic pathways and transcription factors involved have been investigated along with the application of protein engineering to optimize the biorefinery platform. Engineered Microorganisms have been used to produce specific enzymes to breakdown biomass polymers and metabolize sugars to produce ethanol as well other biochemical compounds. Protein engineering strategies have been used for modifying lignocellulolytic enzymes to overcome enzymatic limitations and improving both their production and functionality. Furthermore, promoters and transcription factors, which are key proteins in this process, are modified to promote microbial gene expression that allows a maximum performance of the hydrolytic enzymes for lignocellulosic degradation. The present review will present a critical discussion and highlight the aspects of the use of microorganisms to convert lignocellulose into value-added bioproduct as well combat the bottlenecks to make the biorefinery platform from lignocellulose attractive to the market.
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Affiliation(s)
- Renato Graciano de Paula
- Department of Biochemistry and Immunology, Ribeirao Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
| | | | - Liliane Fraga Costa Ribeiro
- Department of Biochemistry and Immunology, Ribeirao Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Neha Srivastava
- Department of Chemical Engineering & Technology, IIT (BHU), Varanasi 221005, U.P, India
| | - Anthonia O'Donovan
- School of Science and Computing, Galway-Mayo Institute of Technology, Galway, Ireland
| | - P K Mishra
- Department of Chemical Engineering & Technology, IIT (BHU), Varanasi 221005, U.P, India
| | - Vijai K Gupta
- ERA Chair of Green Chemistry, Department of Chemistry and Biotechnology, Tallinn University of Technology, 12618 Tallinn, Estonia.
| | - Roberto N Silva
- Department of Biochemistry and Immunology, Ribeirao Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil.
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Xin F, Dong W, Zhang W, Ma J, Jiang M. Biobutanol Production from Crystalline Cellulose through Consolidated Bioprocessing. Trends Biotechnol 2019; 37:167-180. [DOI: 10.1016/j.tibtech.2018.08.007] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Revised: 08/22/2018] [Accepted: 08/24/2018] [Indexed: 01/08/2023]
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Cheng B, Wang X, Lin Q, Zhang X, Meng L, Sun RC, Xin F, Ren J. New Understandings of the Relationship and Initial Formation Mechanism for Pseudo-lignin, Humins, and Acid-Induced Hydrothermal Carbon. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2018; 66:11981-11989. [PMID: 30376319 DOI: 10.1021/acs.jafc.8b04754] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
The generation of pseudo-lignin as byproduct during the lignocellulose acidic pretreatment has been proposed for many years. However, the detailed formation mechanism is still unclear. Moreover, there is a lack of understanding in the initial reaction during the formation of humins (byproducts in furfural production) and acid-induced hydrothermal carbon (carbon material). In this work, the initial formation of these three substances were investigated. We first found the common feature of their formation process was that carbohydrate-hydrolyzed compounds could form black polymers by condensing in acidic media, but the difference was dependent on the reaction degree. Furthermore, the results revealed that oxidation was an accelerator for condensations during producing black polymers because oxidized compounds could enhance the acidity of the reaction system. However, condensations of oxidized compounds were more difficult to proceed. Meanwhile, during the initial stage, the dominating pathway was that furfural condensed with itself and isomerized xylose via aldol-condensation.
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Affiliation(s)
- Banggui Cheng
- State Key Laboratory of Pulp and Paper Engineering , South China University of Technology , Guangzhou 510640 , China
| | - Xiaohui Wang
- State Key Laboratory of Pulp and Paper Engineering , South China University of Technology , Guangzhou 510640 , China
| | - Qixuan Lin
- State Key Laboratory of Pulp and Paper Engineering , South China University of Technology , Guangzhou 510640 , China
| | - Xiao Zhang
- State Key Laboratory of Pulp and Paper Engineering , South China University of Technology , Guangzhou 510640 , China
| | - Ling Meng
- State Key Laboratory of Pulp and Paper Engineering , South China University of Technology , Guangzhou 510640 , China
| | - Run-Cang Sun
- Center for Lignocellulose Science and Engineering, and Liaoning Key Laboratory Pulp and Paper Engineering , Dalian Polytechnic University , Dalian 116034 , China
| | - Fengxue Xin
- Biotechnology and Pharmaceutical Engineering , Nanjing University of Technology , Nanjing 211800 , China
| | - Junli Ren
- State Key Laboratory of Pulp and Paper Engineering , South China University of Technology , Guangzhou 510640 , China
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Qin Z, Duns GJ, Pan T, Xin F. Consolidated processing of biobutanol production from food wastes by solventogenic Clostridium sp. strain HN4. BIORESOURCE TECHNOLOGY 2018; 264:148-153. [PMID: 29800775 DOI: 10.1016/j.biortech.2018.05.076] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2018] [Revised: 05/18/2018] [Accepted: 05/21/2018] [Indexed: 06/08/2023]
Abstract
In this study, biobutanol production from glucose, starch and food waste by newly identified Clostridium sp. strain HN4 was comprehensively investigated, which is capable of secreting amylase indigenously for the following acetone-butanol-ethanol fermentation. With pH adjustment, strain HN4 could produce 5.23 g/L of butanol from 60 g/L of starch with secretion of 1.95 U/mL amylase through consolidated bioprocessing. Further supplementation of 3 g/L of CaCO3 and 0.5% non-ionic surfactant of Tween 80 could stimulate both amylase activities and the final butanol titer, leading to 17.64 g/L of butanol with yield of 0.15 g/g. Fed batch fermentation integrated with in situ removal could further improve the butanol titer to 35.63 g/L with yield of , representing the highest butanol production and yield from food waste. These unique features of Clostridium sp. strain HN4 could open the door to the possibility of cost-effective biobutanol production from food waste on a large scale.
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Affiliation(s)
- Zuodong Qin
- Key Laboratory of Comprehensive Utilization of Advantage Plants Resources in the South of Hunan, College of Chemistry and Bioengineering, Hunan University of Science and Engineering, Yongzhou 425000, PR China
| | - Gregory J Duns
- Key Laboratory of Comprehensive Utilization of Advantage Plants Resources in the South of Hunan, College of Chemistry and Bioengineering, Hunan University of Science and Engineering, Yongzhou 425000, PR China
| | - Ting Pan
- Key Laboratory of Comprehensive Utilization of Advantage Plants Resources in the South of Hunan, College of Chemistry and Bioengineering, Hunan University of Science and Engineering, Yongzhou 425000, PR China
| | - Fengxue Xin
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, PR China; Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing 211816, PR China.
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Xin F, Yan W, Zhou J, Wu H, Dong W, Ma J, Zhang W, Jiang M. Exploitation of novel wild type solventogenic strains for butanol production. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:252. [PMID: 30250504 PMCID: PMC6145368 DOI: 10.1186/s13068-018-1252-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Accepted: 09/06/2018] [Indexed: 05/17/2023]
Abstract
Butanol has been regarded as an important bulk chemical and advanced biofuel; however, large scaling butanol production by solventogenic Clostridium sp. is still not economically feasible due to the high cost of substrates, low butanol titer and yield caused by the toxicity of butanol and formation of by-products. Renewed interests in biobutanol as biofuel and rapid development in genetic tools have spurred technological advances to strain modifications. Comprehensive reviews regarding these aspects have been reported elsewhere in detail. Meanwhile, more wild type butanol producers with unique properties were also isolated and characterized. However, few reviews addressed these discoveries of novel wild type solventogenic Clostridium sp. strains. Accordingly, this review aims to comprehensively summarize the most recent advances on wild type butanol producers in terms of fermentation patterns, substrate utilization et al. Future perspectives using these native ones as chassis for genetic modification were also discussed.
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Affiliation(s)
- Fengxue Xin
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Puzhu South Road 30#, Nanjing, 211816 People’s Republic of China
- Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing, 211816 People’s Republic of China
| | - Wei Yan
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Puzhu South Road 30#, Nanjing, 211816 People’s Republic of China
| | - Jie Zhou
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Puzhu South Road 30#, Nanjing, 211816 People’s Republic of China
- Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing, 211816 People’s Republic of China
| | - Hao Wu
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Puzhu South Road 30#, Nanjing, 211816 People’s Republic of China
- Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing, 211816 People’s Republic of China
| | - Weiliang Dong
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Puzhu South Road 30#, Nanjing, 211816 People’s Republic of China
- Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing, 211816 People’s Republic of China
| | - Jiangfeng Ma
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Puzhu South Road 30#, Nanjing, 211816 People’s Republic of China
- Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing, 211816 People’s Republic of China
| | - Wenming Zhang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Puzhu South Road 30#, Nanjing, 211816 People’s Republic of China
- Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing, 211816 People’s Republic of China
| | - Min Jiang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Puzhu South Road 30#, Nanjing, 211816 People’s Republic of China
- Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing, 211816 People’s Republic of China
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Cheng B, Zhang X, Lin Q, Xin F, Sun R, Wang X, Ren J. A new approach to recycle oxalic acid during lignocellulose pretreatment for xylose production. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:324. [PMID: 30534202 PMCID: PMC6280388 DOI: 10.1186/s13068-018-1325-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Accepted: 11/29/2018] [Indexed: 05/12/2023]
Abstract
BACKGROUND Dilute oxalic acid pretreatment has drawn much attention because it could selectively hydrolyse the hemicellulose fraction during lignocellulose pretreatment. However, there are few studies focusing on the recovery of oxalic acid. Here, we reported a new approach to recycle oxalic acid used in pretreatment via ethanol extraction. RESULTS The highest xylose content in hydrolysate was 266.70 mg xylose per 1 g corncob (85.0% yield), which was achieved using 150 mmol/L oxalic acid under the optimized treatment condition (140 °C, 2.5 h). These pretreatment conditions were employed to the subsequent pretreatment using recycled oxalic acid. Oxalic acid in the hydrolysate could be recycled according to the following steps: (1) water was removed via evaporation and vacuum drying, (2) ethanol was used to extract oxalic acid in the remaining mixture, and (3) oxalic acid and ethanol were separated by reduced pressure evaporation. The total xylose yields could be stabilized by intermittent adding oxalic acid, and the yields were in range of 46.7-64.3% in this experiment. CONCLUSIONS This sustainable approach of recycling and reuse of oxalic acid has a significant potential application for replacing traditional dilute mineral acid pretreatment of lignocellulose, which could contribute to reduce CO2 emissions and the cost of the pretreatment.
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Affiliation(s)
- Banggui Cheng
- State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou, 510640 China
| | - Xiao Zhang
- State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou, 510640 China
| | - Qixuan Lin
- State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou, 510640 China
| | - Fengxue Xin
- Biotechnology and Pharmaceutical Engineering, Nanjing University of Technology, Nanjing, 211800 China
| | - Runcang Sun
- Centre for Lignocellulose Science and Engineering, and Liaoning Key Laboratory Pulp and Paper Engineering, Dalian Polytechnic University, Dalian, 116034 China
| | - Xiaohui Wang
- State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou, 510640 China
| | - Junli Ren
- State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou, 510640 China
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