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Yang H, Han Y, Peng X. Efficient production of sophorose from glucose and its potentially industrial application in cellulase production. BIORESOURCE TECHNOLOGY 2024; 412:131402. [PMID: 39218367 DOI: 10.1016/j.biortech.2024.131402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2024] [Revised: 08/19/2024] [Accepted: 08/30/2024] [Indexed: 09/04/2024]
Abstract
Sophorose is the most effective inducer for cellulase production by Trichoderma reesei. Currently, the biosynthesis of sophorose is very inefficient, resulting in that unavailable for cellulase production in industry. In this study, CoGH1A, a multifunctional thermophilic glycoside hydrolase, was employed for sophorose production. Under the optimized conditions, the sophorose yield was 37.86 g/L with a productivity of 9.47 g/L/h which is by far the highest productivity. Meanwhile, the Fe3O4-CS-THP-CoGH1A nanoparticles were constructed to realize the recycling of CoGH1A. After 5 cycles of catalysis, Fe3O4-CS-THP-CoGH1A retained about 83.90 % enzyme activity. Finally, the mixtures of glucose and disaccharides (MGDC) obtained after being catalyzed by CoGH1A was used for cellulase production. As a result, the cellulase productivity achieved 188.38 FPU/L/h in 120 h. These results indicated that sophorose could be efficiently produced from glucose via transglycosylation by CoGH1A, making it possible to be industrially used as the inducer to improving the cellulase productivity.
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Affiliation(s)
- Haiqian Yang
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China; Key Laboratory of Biopharmaceutical Preparation and Delivery, Chinese Academy of Sciences, Beijing 100190, China; School of Chemical Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yejun Han
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China; Key Laboratory of Biopharmaceutical Preparation and Delivery, Chinese Academy of Sciences, Beijing 100190, China; School of Chemical Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiaowei Peng
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China; Key Laboratory of Biopharmaceutical Preparation and Delivery, Chinese Academy of Sciences, Beijing 100190, China; School of Chemical Engineering, University of Chinese Academy of Sciences, Beijing 100049, China.
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2
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Zhang Z, Xing J, Li X, Lu X, Liu G, Qu Y, Zhao J. Review of research progress on the production of cellulase from filamentous fungi. Int J Biol Macromol 2024; 277:134539. [PMID: 39122065 DOI: 10.1016/j.ijbiomac.2024.134539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2024] [Revised: 07/29/2024] [Accepted: 08/04/2024] [Indexed: 08/12/2024]
Abstract
Cellulases have been widely used in many fields such as animal feed, textile, food, lignocellulose bioconversion, etc. Efficient and low-cost production of cellulases is very important for its industrial application, especially in bioconversion of lignocellulosic biomass. Filamentous fungi are currently widely used in industrial cellulase production due to their ability to secrete large amounts of active free cellulases extracellularly. This review comprehensively summarized the research progress on cellulases from filamentous fungi in recent years, including filamentous fungi used for cellulase production and its modification strategies, enzyme compositions, characterization methods and application of fungal cellulase systems, and the production of fungal cellulase includes production processes, factors affecting cellulase production such as inducers, fermentation medium, process parameters and their control strategies. Also, the future perspectives and research topics in fungal cellulase production are presented in the end of the review. The review helps to deepen the understanding of the current status of fungal cellulases, thereby promoting the production technology progress and industrial application of filamentous fungal cellulase.
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Affiliation(s)
- Zheng Zhang
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
| | - Jing Xing
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
| | - Xuezhi Li
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
| | - Xianqin Lu
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
| | - Guodong Liu
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
| | - Yinbo Qu
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China.
| | - Jian Zhao
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China.
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3
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Ran X, Gao Y, He X, Wang Z, Mo Y, Li Y. Enhanced glucose-1-phosphate production from corn stover using cellulases with reduced β-glucosidase activity via Trbgl1 gene knockout in Trichoderma reesei Rut C30. Enzyme Microb Technol 2024; 180:110503. [PMID: 39208708 DOI: 10.1016/j.enzmictec.2024.110503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2024] [Revised: 07/30/2024] [Accepted: 08/20/2024] [Indexed: 09/04/2024]
Abstract
The scarcity of cellulases with low β-glucosidase activity poses a significant technological challenge in precisely controlling the partial hydrolysis of lignocellulose to cellobiose, crucial for producing high-value chemicals such as starch, inositol, and NMN. Trichoderma reesei is a primary strain in cellulase production. Therefore, this study targeted the critical β-glucosidase gene, Trbgl1, resulting in over an 86 % reduction in β-glucosidase activity. However, cellulase production decreased by 19.2 % and 20.3 % with lactose or cellulose inducers, respectively. Notably, transcript levels of cellulase genes and overall yield remained unaffected with an inducer containing sophorose. This indicates that β-glucosidase BGL1 converts lactose or cellulose to sophorose through transglycosylation activity, inducing cellulase gene transcription. The resulting enzyme cocktail, comprising recombinant cellulase and cellobiose phosphorylase, was applied for corn stover hydrolysis, resulting in a 24.3 % increase in glucose-1-phosphate yield. These findings provide valuable insights into obtaining enzymes suitable for the high-value utilization of lignocellulose.
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Affiliation(s)
- Xiaoqin Ran
- School of Chemistry and Chemical Engineering, Chongqing University of Science and Technology, Chongqing 401331, China
| | - Yushan Gao
- School of Chemistry and Chemical Engineering, Chongqing University of Science and Technology, Chongqing 401331, China
| | - Xiao He
- School of Chemistry and Chemical Engineering, Chongqing University of Science and Technology, Chongqing 401331, China
| | - Zancheng Wang
- School of Chemistry and Chemical Engineering, Chongqing University of Science and Technology, Chongqing 401331, China
| | - Yi Mo
- School of Chemistry and Chemical Engineering, Chongqing University of Science and Technology, Chongqing 401331, China
| | - Yonghao Li
- School of Chemistry and Chemical Engineering, Chongqing University of Science and Technology, Chongqing 401331, China.
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4
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Liu J, Chen M, Gu S, Fan R, Zhao Z, Sun W, Yao Y, Li J, Tian C. Independent metabolism of oligosaccharides is the keystone of synchronous utilization of cellulose and hemicellulose in Myceliophthora. PNAS NEXUS 2024; 3:pgae053. [PMID: 38380057 PMCID: PMC10877092 DOI: 10.1093/pnasnexus/pgae053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Accepted: 01/29/2024] [Indexed: 02/22/2024]
Abstract
The effective utilization of cellulose and hemicellulose, the main components of plant biomass, is a key technical obstacle that needs to be overcome for the economic viability of lignocellulosic biorefineries. Here, we firstly demonstrated that the thermophilic cellulolytic fungus Myceliophthora thermophila can simultaneously utilize cellulose and hemicellulose, as evidenced by the independent uptake and intracellular metabolism of cellodextrin and xylodextrin. When plant biomass serviced as carbon source, we detected the cellodextrin and xylodextrin both in cells and in the culture medium, as well as high enzyme activities related to extracellular oligosaccharide formation and intracellular oligosaccharide hydrolysis. Sugar consumption assay revealed that in contrast to inhibitory effect of glucose on xylose and cellodextrin/xylodextrin consumption in mixed-carbon media, cellodextrin and xylodextrin were synchronously utilized in this fungus. Transcriptomic analysis also indicated simultaneous induction of the genes involved in cellodextrin and xylodextrin metabolic pathway, suggesting carbon catabolite repression (CCR) is triggered by extracellular glucose and can be eliminated by the intracellular hydrolysis and metabolism of oligosaccharides. The xylodextrin transporter MtCDT-2 was observed to preferentially transport xylobiose and tolerate high cellobiose concentrations, which helps to bypass the inhibition of xylobiose uptake. Furthermore, the expression of cellulase and hemicellulase genes was independently induced by their corresponding inducers, which enabled this strain to synchronously utilize cellulose and hemicellulose. Taken together, the data presented herein will further elucidate the degradation of plant biomass by fungi, with implications for the development of consolidated bioprocessing-based lignocellulosic biorefinery.
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Affiliation(s)
- Jia Liu
- Key Laboratory of Engineering Biology for Low-carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
- National Technology Innovation Center of Synthetic Biology, Tianjin 300308, China
| | - Meixin Chen
- Key Laboratory of Engineering Biology for Low-carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
- National Technology Innovation Center of Synthetic Biology, Tianjin 300308, China
| | - Shuying Gu
- Key Laboratory of Engineering Biology for Low-carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
- National Technology Innovation Center of Synthetic Biology, Tianjin 300308, China
| | - Rui Fan
- Key Laboratory of Engineering Biology for Low-carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
- National Technology Innovation Center of Synthetic Biology, Tianjin 300308, China
| | - Zhen Zhao
- Key Laboratory of Engineering Biology for Low-carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
- National Technology Innovation Center of Synthetic Biology, Tianjin 300308, China
| | - Wenliang Sun
- Key Laboratory of Engineering Biology for Low-carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
- National Technology Innovation Center of Synthetic Biology, Tianjin 300308, China
| | - Yonghong Yao
- Key Laboratory of Engineering Biology for Low-carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
- National Technology Innovation Center of Synthetic Biology, Tianjin 300308, China
| | - Jingen Li
- Key Laboratory of Engineering Biology for Low-carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
- National Technology Innovation Center of Synthetic Biology, Tianjin 300308, China
| | - Chaoguang Tian
- Key Laboratory of Engineering Biology for Low-carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
- National Technology Innovation Center of Synthetic Biology, Tianjin 300308, China
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5
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Luu XC, Shida Y, Suzuki Y, Kuwahara D, Fujimoto T, Takahashi Y, Sato N, Nakamura A, Ogasawara W. Ultrahigh-throughput screening of Trichoderma reesei strains capable of carbon catabolite repression release and cellulase hyperproduction using a microfluidic droplet platform. Biosci Biotechnol Biochem 2023; 87:1393-1406. [PMID: 37550222 DOI: 10.1093/bbb/zbad108] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Accepted: 07/28/2023] [Indexed: 08/09/2023]
Abstract
Trichoderma reesei is the most well-known cellulase producer in the biorefinery industry. Its cellulase biosynthesis is repressed by glucose via carbon catabolite repression (CCR), making CCR-releasing strains with cellulase hyperproduction desirable. Here, we employed a microfluidic droplet platform to culture and screen T. reesei mutants capable of CCR release and cellulase overproduction from extensive mutagenesis libraries. With 3 mutagenesis rounds, about 6.20 × 103 droplets were sorted from a population of 1.51 × 106 droplets in a period of 4.4 h; 76 recovery mutants were screened on flask fermentation, and 2 glucose uptake retarded mutants, MG-9-3 and MG-9-3-30, were eventually isolated. We also generated a hypercellulase producer, M-5, with CCR release via a single mutagenesis round. The hyphal morphology and molecular mechanisms in the mutants were analyzed. This versatile approach combined with a comprehensive understanding of CCR release mechanisms will provide innovative and effective strategies for low-cost cellulase production.
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Affiliation(s)
- Xuan Chinh Luu
- Department of Science of Technology Innovation, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata, Japan
| | - Yosuke Shida
- Department of Materials Science and Bioengineering, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata, Japan
| | - Yoshiyuki Suzuki
- Department of Science of Technology Innovation, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata, Japan
| | - Daiki Kuwahara
- Department of Materials Science and Bioengineering, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata, Japan
| | - Takeshi Fujimoto
- Department of Materials Science and Bioengineering, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata, Japan
| | - Yuka Takahashi
- Department of Materials Science and Bioengineering, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata, Japan
| | - Naomi Sato
- Department of Science of Technology Innovation, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata, Japan
| | - Akihiro Nakamura
- Department of Science of Technology Innovation, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata, Japan
| | - Wataru Ogasawara
- Department of Science of Technology Innovation, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata, Japan
- Department of Materials Science and Bioengineering, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata, Japan
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6
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Zhang S, Ni D, Zhu Y, Xu W, Zhang W, Mu W. A comprehensive review on the properties, production, and applications of functional glucobioses. Crit Rev Food Sci Nutr 2023:1-14. [PMID: 37819266 DOI: 10.1080/10408398.2023.2261053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/13/2023]
Abstract
Glucobiose is a range of disaccharides consisting of two glucose molecules, generally including trehalose, kojibiose, sophorose, nigerose, laminaribiose, maltose, cellobiose, isomaltose, and gentiobiose. The difference glycosidic bonds of two glucose molecules result in the diverse molecular structures, physiochemical properties and physiological functions of these glucobioses. Some glucobioses are abundant in nature but have unconspicuous roles on health like maltose, whereas some rare glucobioses display remarkable biological effects. It is unpractical process to extract these rare glucobioses from natural resources, while biological synthesis is a feasible approach. Recently, the production and application of glucobiose have attracted considerable attention. This review provides a comprehensive overview of glucobioses, including their natural sources and physicochemical properties like structure, sweetness, digestive performance, toxicology, and cariogenicity. Specific enzymes used for the production of various glucobioses and fermentation production processes are summarized. Additionally, their versatile functions and broad applications are also introduced.
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Affiliation(s)
- Shuqi Zhang
- State Key Laboratory of Food Science and Resoruces, Jiangnan University, Wuxi, Jiangsu, China
| | - Dawei Ni
- State Key Laboratory of Food Science and Resoruces, Jiangnan University, Wuxi, Jiangsu, China
| | - Yingying Zhu
- State Key Laboratory of Food Science and Resoruces, Jiangnan University, Wuxi, Jiangsu, China
| | - Wei Xu
- State Key Laboratory of Food Science and Resoruces, Jiangnan University, Wuxi, Jiangsu, China
| | - Wenli Zhang
- State Key Laboratory of Food Science and Resoruces, Jiangnan University, Wuxi, Jiangsu, China
| | - Wanmeng Mu
- State Key Laboratory of Food Science and Resoruces, Jiangnan University, Wuxi, Jiangsu, China
- International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, Jiangsu, China
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7
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Yang J, Yue HR, Pan LY, Feng JX, Zhao S, Suwannarangsee S, Chempreda V, Liu CG, Zhao XQ. Fungal strain improvement for efficient cellulase production and lignocellulosic biorefinery: Current status and future prospects. BIORESOURCE TECHNOLOGY 2023:129449. [PMID: 37406833 DOI: 10.1016/j.biortech.2023.129449] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 06/29/2023] [Accepted: 07/01/2023] [Indexed: 07/07/2023]
Abstract
Lignocellulosic biomass (LCB) has been recognized as a valuable carbon source for the sustainable production of biofuels and value-added biochemicals. Crude enzymes produced by fungal cell factories benefit economic LCB degradation. However, high enzyme production cost remains a great challenge. Filamentous fungi have been widely used to produce cellulolytic enzymes. Metabolic engineering of fungi contributes to efficient cellulase production for LCB biorefinery. Here the latest progress in utilizing fungal cell factories for cellulase production was summarized, including developing genome engineering tools to improve the efficiency of fungal cell factories, manipulating promoters, and modulating transcription factors. Multi-omics analysis of fungi contributes to identifying novel genetic elements for enhancing cellulase production. Furthermore, the importance of translation regulation of cellulase production are emphasized. Efficient development of fungal cell factories based on integrative strain engineering would benefit the overall bioconversion efficacy of LCB for sustainable bioproduction.
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Affiliation(s)
- Jie Yang
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Hou-Ru Yue
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Li-Ya Pan
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi Research Center for Microbial and Enzyme Engineering Technology, College of Life Science and Technology, Guangxi University, Nanning 530004, China
| | - Jia-Xun Feng
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi Research Center for Microbial and Enzyme Engineering Technology, College of Life Science and Technology, Guangxi University, Nanning 530004, China
| | - Shuai Zhao
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi Research Center for Microbial and Enzyme Engineering Technology, College of Life Science and Technology, Guangxi University, Nanning 530004, China
| | - Surisa Suwannarangsee
- National Center for Genetic Engineering and Biotechnology (BIOTEC), 113 Thailand Science Park, Phaholyothin Road, Khlong Luang, Pathumthani 12120, Thailand
| | - Verawat Chempreda
- National Center for Genetic Engineering and Biotechnology (BIOTEC), 113 Thailand Science Park, Phaholyothin Road, Khlong Luang, Pathumthani 12120, Thailand
| | - Chen-Guang Liu
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Xin-Qing Zhao
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China.
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Singh N, Sithole B, Kumar A, Govinden R. A glucose tolerant β-glucosidase from a newly isolated Neofusicoccum parvum strain F7: production, purification, and characterization. Sci Rep 2023; 13:5134. [PMID: 36991150 PMCID: PMC10060427 DOI: 10.1038/s41598-023-32353-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Accepted: 03/26/2023] [Indexed: 03/31/2023] Open
Abstract
Cellulase-producing microorganisms produce low titres of β-glucosidases with low tolerance to glucose. This study aimed to improve production, purify, and characterize a β-glucosidase from a newly isolated Neofusicoccum parvum strain F7. β-Glucosidase production was significantly enhanced by a sequential statistical modelling approach from 1.5-fold in Plackett-Burman design to 2.5 U/ml in the Box-Behnken design compared to the preliminary one variable at a time experiments (1.6 U/ml). The optimal conditions for enzyme production by BBD were 12 days of fermentation at 20 °C, 175 rpm, 0.5% glycerol and 1.5% casein in pH 6.0 buffer. Three β-glucosidase isoforms referred to as Bgl1, Bgl2, Bgl3 were purified and characterized from the optimized crude extract displaying IC50 values of 2.6, 22.6 and 319.5 mM for glucose, respectively. Bgl3 with a molecular mass of approximately 65 kDa demonstrated the highest tolerance to glucose among the isoforms. The optimum activity and stability for Bgl3 was observed at pH 4.0 in 50 mM sodium acetate buffer with 80% β-glucosidase residual activity retained for three hours. This isoform also retained 60% residual activity at 65 °C for one hour which was then reduced to 40% which remained stable for another 90 min. The β-glucosidase activity of Bgl3 was not enhanced after the addition of metal ions in assay buffers. The Km and vmax for 4-nitrophenyl-β-D-glucopyranoside were 1.18 mM and 28.08 µmol/min, respectively indicating high affinity for the substrate. The ability to withstand the presence of glucose in conjunction with its thermophilic nature indicates promise for this enzyme in industrial application.
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Affiliation(s)
- Nivisti Singh
- Discipline of Microbiology, School of Life Sciences, Westville Campus, University of KwaZulu-Natal, Durban, South Africa.
| | - Bruce Sithole
- Discipline of Engineering, Howard Campus, University of KwaZulu-Natal, Durban, South Africa
- Biorefinery Industry Development Facility, Council for Scientific and Industrial Research, Durban, South Africa
| | - Ajit Kumar
- Discipline of Microbiology, School of Life Sciences, Westville Campus, University of KwaZulu-Natal, Durban, South Africa
| | - Roshini Govinden
- Discipline of Microbiology, School of Life Sciences, Westville Campus, University of KwaZulu-Natal, Durban, South Africa
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Two-Stage Pretreatment of Jerusalem Artichoke Stalks with Wastewater Recycling and Lignin Recovery for the Biorefinery of Lignocellulosic Biomass. Processes (Basel) 2023. [DOI: 10.3390/pr11010127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Jerusalem artichoke (Helianthus tuberosus L.) is emerging as one of the energy plants considered for biofuel production. Alkali and alkali-involved pretreatment methods have been widely used for the bioconversion of cellulosic materials due to their high sugar yield and low inhibitor release. However, the recovery and treatment of wastewater (black liquor) have been poorly studied. Here, we present a novel two-stage pretreatment process design for recycling black liquor. Jerusalem artichoke stalk (JAS) was first treated with 2% (w/v) NaOH, after which lignin was recovered by H2SO4 at pH 2.0 from the black liquor. The recycled solutions were subsequently used to treat the NaOH-pretreated JAS for the second time to dissolve hemicellulose. CO-pretreated JAS, hydrolysates, and acid-insoluble lignin were obtained after the above-mentioned two-stage pretreatment. A reducing sugar yield of 809.98 mg/g Co-pretreated JAS was achieved after 48 h at 5% substrate concentration using a cellulase dosage of 25 FPU/g substrate. In addition, hydrolysates containing xylose and acid-insoluble lignin were obtained as byproducts. The pretreatment strategy described here using alkali and acid combined with wastewater recycling provides an alternative approach for cellulosic biorefinery.
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10
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Li J, Chen Y, Gao Y, Mo Y, Long T, Yao B, Li Y. Engineering Trichoderma reesei for the hyperproduction of cellulose induced protein 1 (Cip1) on a sophorose-containing inducer to efficiently saccharify alkali-pretreated corn stover. Prep Biochem Biotechnol 2022:1-11. [PMID: 36563056 DOI: 10.1080/10826068.2022.2158469] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Trichoderma reesei was induced to produce cellulase by a combination of glucose and β-disaccharide; however, lower levels of auxiliary proteins for degrading lignocellulosic biomass were detected by iTRAQ analysis compared with cellulose as an inducer, especially cellulose induced protein 1 (CIP1). In this study, A pdc1 promoter-driven overexpression of the endogenous Trcip1 gene was observed in T. reesei Rut C30, and the Trcip1 transcription levels of the two transformants, T. reesei OE-cip1-1 and OE-cip1-2, demonstrated 31.2- and 164.6-fold increases, respectively, but there was no significant change in cellobiohydrolase, endoglucanase and filter paper activity at 48 h. The crude enzyme was then used to hydrolyze corn stover. For T. reesei OE-cip1-1 and OE-cip1-2, the hydrolysis efficiency increased by 25.0 and 28.6% with a solid loading of 5% at 2 h, respectively. Simultaneously, 85.5 and 85.2 g/L glucose were released using a cellulase cocktail at high solid loading (20%), and these glucose release rates were significantly greater than that of T. reesei Rut C30 cellulase (77.4 g/L) at 120 h. Furthermore, scanning electron microscopy (SEM) and X-ray diffraction (XRD) showed that the enhanced hydrolysis efficiency was primarily triggered by the decrease in the crystallinity of lignocellulose, and the fiber structure had varying degrees of loosening and disintegration.
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Affiliation(s)
- Jianghong Li
- Chongqing Key Laboratory of Industrial Fermentation Microorganism, School of Chemistry and Chemical Engineering, Chongqing University of Science and Technology, Chongqing, China
| | - Yudian Chen
- Chongqing Key Laboratory of Industrial Fermentation Microorganism, School of Chemistry and Chemical Engineering, Chongqing University of Science and Technology, Chongqing, China
| | - Yushan Gao
- Chongqing Key Laboratory of Industrial Fermentation Microorganism, School of Chemistry and Chemical Engineering, Chongqing University of Science and Technology, Chongqing, China
| | - Yi Mo
- Chongqing Key Laboratory of Industrial Fermentation Microorganism, School of Chemistry and Chemical Engineering, Chongqing University of Science and Technology, Chongqing, China
| | - Tingting Long
- Chongqing Key Laboratory of Industrial Fermentation Microorganism, School of Chemistry and Chemical Engineering, Chongqing University of Science and Technology, Chongqing, China
| | - Bo Yao
- Chongqing Key Laboratory of Industrial Fermentation Microorganism, School of Chemistry and Chemical Engineering, Chongqing University of Science and Technology, Chongqing, China
| | - Yonghao Li
- Chongqing Key Laboratory of Industrial Fermentation Microorganism, School of Chemistry and Chemical Engineering, Chongqing University of Science and Technology, Chongqing, China
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11
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Singh N, Sithole B, Govinden R. Screening for cellulases and preliminary optimisation of glucose tolerant β-glucosidase production and characterisation. Mycology 2022; 14:91-107. [PMID: 37152851 PMCID: PMC10161942 DOI: 10.1080/21501203.2022.2155261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The search for a novel microbial producer of cellulases including a glucose tolerant β-glucosidase is a challenge as most are inhibited by their product glucose. This study aims to screen for cellulolytic fungi using qualitative and quantitative screening methods. Primary screening revealed 34 of 46 fungal isolates with β-glucosidase activity. Eleven and 13 of these also displayed endoglucanase and exoglucanase activities, respectively. During secondary screening, this number was reduced to 26 β-glucosidase producers with 13 also having endoglucanase and exoglucanase activities. Isolate C1 displayed enhanced production of β-glucosidases in the presence of 0.05 M glucose (69% higher activity). Optimisation of growth conditions for β-glucosidase production by one variable at a time experiments improved production for (isolates) PS1 (64%), MB5 (84%), and C2 (69%). Isolate PS1 identified as Chaetomella sp. BBA70074 displayed the highest tolerance to glucose, retaining 10% of β-glucosidase activity in the presence of 0.8 M glucose. Tolerance to glucose increased to 14% when produced under optimal conditions. β-Glucosidase had a molecular weight of 170 kDa with a pH and temperature optima of 6 and 70°C, respectively. Future studies will include optimisation of the production of the glucose tolerant enzyme by Chaetomella sp. BBA70074.
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Affiliation(s)
- Nivisti Singh
- Discipline of Microbiology, School of Life Sciences, Westville Campus, University of KwaZulu-Natal, Durban, South Africa
| | - Bruce Sithole
- Discipline of Engineering, Howard Campus, University of KwaZulu-Natal, Durban, South Africa
- Biorefinery Industry Development Facility, Council for Scientific and Industrial Research, Durban, South Africa
| | - Roshini Govinden
- Discipline of Microbiology, School of Life Sciences, Westville Campus, University of KwaZulu-Natal, Durban, South Africa
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