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Xu X, Jiang Y, Yeo QX, Zhou W. Purification and characterization of betacyanin monomers from Hylocereus polyrhizus peel: A comparative study of their antioxidant and antidiabetic activities with mechanistic insights. Food Chem 2024; 451:139467. [PMID: 38678661 DOI: 10.1016/j.foodchem.2024.139467] [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: 07/08/2023] [Revised: 04/14/2024] [Accepted: 04/22/2024] [Indexed: 05/01/2024]
Abstract
Betacyanins have garnered escalating research interest for their promising bioactivities. However, substantial challenges in purification and separation have impeded a holistic comprehension of the distinct bioactivities of individual betacyanins and their underlying mechanisms. Herein, betanin and phyllocactin monomers with purity exceeding 95% were successfully obtained from Hylocereus polyrhizus peel using a feasible protocol. These monomers were subsequently employed for comparative bioactivity assessments to uncover underlying mechanisms and illuminate structure-activity relationships. Interestingly, phyllocactin exhibited superior antioxidant activities and 36.1% stronger inhibitory activity on α-glucosidase compared to betanin. Mechanistic studies have revealed that they function as mixed-type inhibitors of α-amylase and competitive inhibitors of α-glucosidase, with interactions predominantly driven by hydrogen bonding. Notably, phyllocactin demonstrated a greater binding affinity with enzymes than betanin, thereby substantiating its heightened inhibitory activity. Overall, our results highlight novel bioactivities of betacyanin monomers and provide profound insights into the intricate interplay between structures and properties.
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Affiliation(s)
- Xiaojuan Xu
- Department of Food Science and Technology, National University of Singapore, 2 Science Drive 2, Singapore 117542, Republic of Singapore
| | - Yingfen Jiang
- Department of Food Science and Technology, National University of Singapore, 2 Science Drive 2, Singapore 117542, Republic of Singapore
| | - Qi Xuan Yeo
- Department of Food Science and Technology, National University of Singapore, 2 Science Drive 2, Singapore 117542, Republic of Singapore
| | - Weibiao Zhou
- Department of Food Science and Technology, National University of Singapore, 2 Science Drive 2, Singapore 117542, Republic of Singapore; National University of Singapore (Suzhou) Research Institute, 377 Linquan Street, Suzhou Industrial Park, Jiangsu 215123, China.
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2
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Ma D, Chen H, Liu D, Feng C, Hua Y, Gu T, Guo X, Zhou Y, Wang H, Tong G, Li H, Zhang K. Soil-derived cellulose-degrading bacteria: screening, identification, the optimization of fermentation conditions, and their whole genome sequencing. Front Microbiol 2024; 15:1409697. [PMID: 39050626 PMCID: PMC11266136 DOI: 10.3389/fmicb.2024.1409697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2024] [Accepted: 06/27/2024] [Indexed: 07/27/2024] Open
Abstract
Straw cellulose is an abundant renewable resource in nature. In recent years, the conversion of cellulose from waste straw into biofuel by specific microorganisms' fragmentation has attracted extensive attention. Although many bacteria with the ability to degrade cellulose have been identified, comprehensive bioinformatics analyses of these bacteria remain limited, and research exploring optimal fragmentation conditions is scarce. Our study involved the isolation and screening of bacteria from various locations in Yangzhou using carboxymethyl cellulose (CMC) media. Then, the cellulose-degrading bacteria were identified using 16S rRNA and seven candidate bacterial strains with cellulose degrading ability were identified in Yangzhou city for the first time. The cellulase activity was determined by the 3,5-dinitrosalicylic acid (DNS) method in different fragmentation conditions, and finally two bacteria strains with the strongest cellulose degradation ability were selected for whole genome sequencing analysis. Sequencing results revealed that the genome sizes of Rhodococcus wratislaviensis YZ02 and Pseudomonas Xanthosomatis YZ03 were 8.51 Mb and 6.66 Mb, containing 8,466 and 5,745 genes, respectively. A large number of cellulose degradation-related genes were identified and annotated using KEGG, GO and COG analyses. In addition, genomic CAZyme analysis indicated that both R. wratislaviensis YZ02 and P. Xanthosomatis YZ03 harbor a series of glycoside hydrolase family (GH) genes and other genes related to cellulose degradation. Our finding provides new options for the development of cellulose-degrading bacteria and a theoretical basis for improving the cellulose utilization of straw.
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Affiliation(s)
- Degao Ma
- Yangzhou Environmental Monitoring Center of Jiangsu Province, Yangzhou, China
| | - Haoyu Chen
- College of Plant Protection, Yangzhou University, Yangzhou, China
| | - Duxuan Liu
- College of Plant Protection, Yangzhou University, Yangzhou, China
| | - Chenwei Feng
- College of Plant Protection, Yangzhou University, Yangzhou, China
| | - Yanhong Hua
- College of Plant Protection, Yangzhou University, Yangzhou, China
| | - Tianxiao Gu
- College of Plant Protection, Yangzhou University, Yangzhou, China
| | - Xiao Guo
- College of Plant Protection, Yangzhou University, Yangzhou, China
| | - Yuchen Zhou
- Department of Pharmacy, Medical School of Yangzhou University, Yangzhou University, Yangzhou, China
| | - Houjun Wang
- Yangzhou Environmental Monitoring Center of Jiangsu Province, Yangzhou, China
| | - Guifeng Tong
- Yangzhou Environmental Monitoring Center of Jiangsu Province, Yangzhou, China
| | - Hua Li
- College of Engineering, Nanjing Agricultural University, Nanjing, China
| | - Kun Zhang
- College of Plant Protection, Yangzhou University, Yangzhou, China
- Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education of China, Yangzhou University, Yangzhou, China
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3
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Nong D, Haviland ZK, Zexer N, Pfaff SA, Cosgrove DJ, Tien M, Anderson CT, Hancock WO. Single-molecule tracking reveals dual front door/back door inhibition of Cel7A cellulase by its product cellobiose. Proc Natl Acad Sci U S A 2024; 121:e2322567121. [PMID: 38648472 PMCID: PMC11067010 DOI: 10.1073/pnas.2322567121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Accepted: 03/18/2024] [Indexed: 04/25/2024] Open
Abstract
Degrading cellulose is a key step in the processing of lignocellulosic biomass into bioethanol. Cellobiose, the disaccharide product of cellulose degradation, has been shown to inhibit cellulase activity, but the mechanisms underlying product inhibition are not clear. We combined single-molecule imaging and biochemical investigations with the goal of revealing the mechanism by which cellobiose inhibits the activity of Trichoderma reesei Cel7A, a well-characterized exo-cellulase. We find that cellobiose slows the processive velocity of Cel7A and shortens the distance moved per encounter; effects that can be explained by cellobiose binding to the product release site of the enzyme. Cellobiose also strongly inhibits the binding of Cel7A to immobilized cellulose, with a Ki of 2.1 mM. The isolated catalytic domain (CD) of Cel7A was also inhibited to a similar degree by cellobiose, and binding of an isolated carbohydrate-binding module to cellulose was not inhibited by cellobiose, suggesting that cellobiose acts on the CD alone. Finally, cellopentaose inhibited Cel7A binding at micromolar concentrations without affecting the enzyme's velocity of movement along cellulose. Together, these results suggest that cellobiose inhibits Cel7A activity both by binding to the "back door" product release site to slow activity and to the "front door" substrate-binding tunnel to inhibit interaction with cellulose. These findings point to strategies for engineering cellulases to reduce product inhibition and enhance cellulose degradation, supporting the growth of a sustainable bioeconomy.
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Affiliation(s)
- Daguan Nong
- Department of Biomedical Engineering, Pennsylvania State University, University Park, PA16802
| | - Zachary K. Haviland
- Department of Biomedical Engineering, Pennsylvania State University, University Park, PA16802
| | - Nerya Zexer
- Department of Biology, Pennsylvania State University, University Park, PA16802
| | - Sarah A. Pfaff
- Department of Biology, Pennsylvania State University, University Park, PA16802
- Intercollege Graduate Degree Program in Plant Biology, Department of Biology, The Pennsylvania State University, University Park, PA16802
| | - Daniel J. Cosgrove
- Department of Biology, Pennsylvania State University, University Park, PA16802
| | - Ming Tien
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, PA16802
| | - Charles T. Anderson
- Department of Biology, Pennsylvania State University, University Park, PA16802
| | - William O. Hancock
- Department of Biomedical Engineering, Pennsylvania State University, University Park, PA16802
- Department of Chemistry, Pennsylvania State University, University Park, PA16802
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4
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Xi S, Kong H, Ban X, Li C, Gu Z, Li Z. Bifunctional Mutant of Oligo-1,6-glucosidase for the Production of Glucose from Glucose Mother Liquor. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2023; 71:13035-13042. [PMID: 37607409 DOI: 10.1021/acs.jafc.3c03731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/24/2023]
Abstract
Glucose mother liquor (GML) is a byproduct of the glucose (G1) crystallization process. However, the presence of maltooligosaccharides and isomaltooligosaccharides within GML imposes limitations on its reutilization. Furthermore, the high concentration of G1 in GML leads to product inhibition of G1-producing enzymes. To overcome these challenges, a variant enzyme called V219A was developed through genetic mutation. The V219A exhibits the ability to hydrolyze both maltooligosaccharides and isomaltooligosaccharides. Product inhibition kinetics showed that the IC50 value of V219A was 7 times higher than that of the wild type. Upon subjecting primary, secondary, and tertiary GML to treatment with V219A, the G1 content exhibited notable increases, reaching 96.88, 95.70, and 90.46%, respectively. These significant findings not only establish an innovative and environmentally conscious approach for G1 production from GML but also provide a promising strategy for enzyme construction that caters to the demands of industrial-scale production.
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Affiliation(s)
- Shixia Xi
- School of Food Science and Technology, Jiangnan University, Wuxi 214122, People's Republic of China
| | - Haocun Kong
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, People's Republic of China
- School of Food Science and Technology, Jiangnan University, Wuxi 214122, People's Republic of China
- Collaborative Innovation Center of Food Safety and Quality Control, Jiangnan University, Wuxi 214122, People's Republic of China
| | - Xiaofeng Ban
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, People's Republic of China
- School of Food Science and Technology, Jiangnan University, Wuxi 214122, People's Republic of China
- Collaborative Innovation Center of Food Safety and Quality Control, Jiangnan University, Wuxi 214122, People's Republic of China
| | - Caiming Li
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, People's Republic of China
- School of Food Science and Technology, Jiangnan University, Wuxi 214122, People's Republic of China
- Collaborative Innovation Center of Food Safety and Quality Control, Jiangnan University, Wuxi 214122, People's Republic of China
| | - Zhengbiao Gu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, People's Republic of China
- School of Food Science and Technology, Jiangnan University, Wuxi 214122, People's Republic of China
- Collaborative Innovation Center of Food Safety and Quality Control, Jiangnan University, Wuxi 214122, People's Republic of China
| | - Zhaofeng Li
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, People's Republic of China
- School of Food Science and Technology, Jiangnan University, Wuxi 214122, People's Republic of China
- Collaborative Innovation Center of Food Safety and Quality Control, Jiangnan University, Wuxi 214122, People's Republic of China
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5
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Wen P, Chen Z, Lian Z, Zhang J. Efficient production of high concentration monosaccharides and ethanol from poplar wood after delignification and deacetylation. BIORESOURCE TECHNOLOGY 2023:129459. [PMID: 37419287 DOI: 10.1016/j.biortech.2023.129459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Revised: 07/02/2023] [Accepted: 07/03/2023] [Indexed: 07/09/2023]
Abstract
Efficient enzymatic hydrolysis is required for production of high concentration monosaccharides and ethanol. The lignin and acetyl group in poplar can limit the enzymatic hydrolysis. However, the effect of delignification combined with deacetylation on the saccharification of poplar for high concentration monosaccharides was not clear. Herein, hydrogen peroxide-acetic acid (HPAA) was used for delignification and sodium hydroxide was used for deacetylation to enhance the hydrolyzability of poplar. Delignification with 60% HPAA at 80 °C could remove 81.9% lignin. Acetyl group was completely removed with 0.5% NaOH at 60 °C. After saccharification, 318.1 g/L monosaccharides were obtained with a poplar loading of 35% (w/v). After simultaneous saccharification and fermentation, 114.9 g/L bioethanol was gained from delignified and deacetylated poplar. Those results showed the highest monosaccharides and ethanol concentrations in reported research. This developed strategy with relatively low temperature could effectively improve the production of high concentration monosaccharide and ethanol from poplar.
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Affiliation(s)
- Peiyao Wen
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China
| | - Zhangjing Chen
- Department of Sustainable Biomaterials Virginia Tech University, 1650 Research Center Drive, Blacksburg, VA 24060, USA
| | - Zhina Lian
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China; Key Laboratory of Forestry Genetics & Biotechnology (Nanjing Forestry University), Ministry of Education, Nanjing 210037, China; Jiangsu Province Key Laboratory of Green Biomass-based Fuels and Chemicals, Nanjing 210037, China
| | - Junhua Zhang
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China; Key Laboratory of Forestry Genetics & Biotechnology (Nanjing Forestry University), Ministry of Education, Nanjing 210037, China; Jiangsu Province Key Laboratory of Green Biomass-based Fuels and Chemicals, Nanjing 210037, China.
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6
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Christopher M, Sreeja-Raju A, Abraham A, Gokhale DV, Pandey A, Sukumaran RK. Early cellular events and potential regulators of cellulase induction in Penicillium janthinellum NCIM 1366. Sci Rep 2023; 13:5057. [PMID: 36977777 PMCID: PMC10050438 DOI: 10.1038/s41598-023-32340-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Accepted: 03/26/2023] [Indexed: 03/30/2023] Open
Abstract
Cellulase production by fungi is tightly regulated in response to environmental cues, and understanding this mechanism is a key pre-requisite in the efforts to improve cellulase secretion. Based on UniProt descriptions of secreted Carbohydrate Active enZymes (CAZymes), 13 proteins of the cellulase hyper-producer Penicillium janthinellum NCIM 1366 (PJ-1366) were annotated as cellulases- 4 cellobiohydrolases (CBH), 7 endoglucanases (EG) and 2 beta glucosidases (BGL). Cellulase, xylanase, BGL and peroxidase activities were higher for cultures grown on a combination of cellulose and wheat bran, while EG was stimulated by disaccharides. Docking studies indicated that the most abundant BGL- Bgl2- has different binding sites for the substrate cellobiose and the product glucose, which helps to alleviate feedback inhibition, probably accounting for the low level of glucose tolerance exhibited. Out of the 758 transcription factors (TFs) differentially expressed on cellulose induction, 13 TFs were identified whose binding site frequencies on the promoter regions of the cellulases positively correlated with their abundance in the secretome. Further, correlation analysis of the transcriptional response of these regulators and TF-binding sites on their promoters indicated that cellulase expression is possibly preceded by up-regulation of 12 TFs and down-regulation of 16 TFs, which cumulatively regulate transcription, translation, nutrient metabolism and stress response.
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Affiliation(s)
- Meera Christopher
- Biofuels and Biorefineries Section, Microbial Processes and Technology Division, CSIR- National Institute for Interdisciplinary Science and Technology, Industrial Estate P.O., Pappanamcode, Thiruvananthapuram, Kerala, 695019, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad- 201002, India
| | - AthiraRaj Sreeja-Raju
- Biofuels and Biorefineries Section, Microbial Processes and Technology Division, CSIR- National Institute for Interdisciplinary Science and Technology, Industrial Estate P.O., Pappanamcode, Thiruvananthapuram, Kerala, 695019, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad- 201002, India
| | - Amith Abraham
- Department of Chemical Engineering, Hanyang University, Seoul, Republic of Korea
| | | | - Ashok Pandey
- Centre for Innovation and Translational Research, CSIR-Indian Institute of Toxicology Research, Lucknow, 226 001, Uttar Pradesh, India
- Sustainability Cluster, School of Engineering, University of Petroleum and Energy Studies, Dehradun, 248 007, India
- Centre for Energy and Environmental Sustainability, Lucknow, 226 029, India
| | - Rajeev K Sukumaran
- Biofuels and Biorefineries Section, Microbial Processes and Technology Division, CSIR- National Institute for Interdisciplinary Science and Technology, Industrial Estate P.O., Pappanamcode, Thiruvananthapuram, Kerala, 695019, India.
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad- 201002, India.
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7
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Wu J, Dong Y, Zhang H, Liu J, Renneckar S, Saddler J. Reduced cellulose accessibility slows down enzyme-mediated hydrolysis of cellulose. BIORESOURCE TECHNOLOGY 2023; 371:128647. [PMID: 36681353 DOI: 10.1016/j.biortech.2023.128647] [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: 12/21/2022] [Revised: 01/13/2023] [Accepted: 01/16/2023] [Indexed: 06/17/2023]
Abstract
Enzyme-mediated hydrolysis of cellulose always starts with an initial rapid phase, which gradually slows down, sometimes resulting in incomplete cellulose hydrolysis even after prolonged incubation. Although mechanisms such as end-product inhibition are known to play a role, the predominant mechanism appears to be reduced cellulose accessibility to the enzymes. When using Simon's stain to quantify accessibility, the accessibility of mechanically disintegrated and phosphoric acid-swollen cellulose substrates decreased as hydrolysis proceeded. In contrast, the poor initial accessibility of Avicel remained low throughout hydrolysis. However, washing the residual cellulose increased cellulose accessibility, likely due to the removal of tightly bound but non-productive enzymes which blocked access to more active enzymes in solution. Atomic force microscopy (AFM) analysis of the initial and residual cellulose collected when the hydrolysis plateaued, showed an increase in the roughness of the cellulose surface, possibly resulting in the tighter binding of less active cellulases.
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Affiliation(s)
- Jie Wu
- Forest Product Biotechnology/Bioenergy Group, Department of Wood Science, Faculty of Forestry, University of British Columbia, 2424 Main Mall, Vancouver, British Columbia V6T 1Z4, Canada
| | - Yintian Dong
- Forest Product Biotechnology/Bioenergy Group, Department of Wood Science, Faculty of Forestry, University of British Columbia, 2424 Main Mall, Vancouver, British Columbia V6T 1Z4, Canada
| | - Huaiyu Zhang
- Advanced Renewable Materials Lab, Department of Wood Science, Faculty of Forestry, University of British Columbia, 2424 Main Mall, Vancouver, British Columbia V6T 1Z4, Canada
| | - Jingyun Liu
- Forest Product Biotechnology/Bioenergy Group, Department of Wood Science, Faculty of Forestry, University of British Columbia, 2424 Main Mall, Vancouver, British Columbia V6T 1Z4, Canada; School of Chemical Engineering, Sichuan University, Chengdu 610065, China
| | - Scott Renneckar
- Advanced Renewable Materials Lab, Department of Wood Science, Faculty of Forestry, University of British Columbia, 2424 Main Mall, Vancouver, British Columbia V6T 1Z4, Canada
| | - Jack Saddler
- Forest Product Biotechnology/Bioenergy Group, Department of Wood Science, Faculty of Forestry, University of British Columbia, 2424 Main Mall, Vancouver, British Columbia V6T 1Z4, Canada.
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8
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Luo H, Liu X, Yu D, Yuan J, Tan J, Li H. Research Progress on Lignocellulosic Biomass Degradation Catalyzed by Enzymatic Nanomaterials. Chem Asian J 2022; 17:e202200566. [PMID: 35862657 DOI: 10.1002/asia.202200566] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 07/21/2022] [Indexed: 11/11/2022]
Abstract
Lignocellulose biomass (LCB) has extensive applications in many fields such as bioenergy, food, medicines, and raw materials for producing value-added products. One of the keys to efficient utilization of LCB is to obtain directly available oligo- and monomers (e.g., glucose). With the characteristics of easy recovery and separation, high efficiency, economy, and environmental protection, immobilized enzymes have been developed as heterogeneous catalysts to degrade LCB effectively. In this review, applications and mechanisms of LCB-degrading enzymes are discussed, and the nanomaterials and methods used to immobilize enzymes are also discussed. Finally, the research progress of lignocellulose biodegradation catalyzed by nano-enzymes was discussed.
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Affiliation(s)
- Hangyu Luo
- Guiyang University, College of Biology and Environmental Engineering, CHINA
| | - Xiaofang Liu
- Guiyang University, College of Biology and Environmental Engineering, CHINA
| | - Dayong Yu
- Guiyang University, College of Biology and Environmental Engineering, CHINA
| | - Junfa Yuan
- Guizhou University, Center for R&D of Fine Chemicals, CHINA
| | - Jinyu Tan
- Guizhou University, Center for R&D of Fine Chemicals, CHINA
| | - Hu Li
- Guizhou University, Center for R&D of Fine Chemicals, Huaxi Street, 550025, Guiyang, CHINA
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9
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Tang S, Ma Y, Dong X, Zhou H, He Y, Ren D, Wang Q, Yang H, Liu S, Wu L. Enzyme-assisted extraction of fucoidan from Kjellmaniella crassifolia based on kinetic study of enzymatic hydrolysis of algal cellulose. ALGAL RES 2022. [DOI: 10.1016/j.algal.2022.102795] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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10
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Chourasia VR, Bisht M, Pant KK, Henry RJ. Unveiling the potential of water as a co-solvent in microwave-assisted delignification of sugarcane bagasse using ternary deep eutectic solvents. BIORESOURCE TECHNOLOGY 2022; 351:127005. [PMID: 35301085 DOI: 10.1016/j.biortech.2022.127005] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 03/09/2022] [Accepted: 03/11/2022] [Indexed: 06/14/2023]
Abstract
Deep eutectic solvents (DESs) have become popular owing to their biodegradability and recyclability. In this study, the influence of water as a co-solvent is demonstrated to enhance the properties of choline based ternary DESs. A fast and energy-efficient microwave-assisted pre-treatment process was developed for delignification of sugarcane bagasse (SB). The effectiveness of SB fractionation was revealed by incorporating Lewis acids (MgCl2.6H20, NiCl2.6H20) with the DESs for pre-treatment and Choline chloride: Ethylene glycol: NiCl2.6H20 (CC:EG:NI) at a molar ratio 1:2:0.016 with 20w% water as a co-solvent provided the most promising result, with 84% delignification and 99% enzyme digestibility. Water was also employed as an anti-solvent to facilitate lignin solubility and exhibited up to 26w% lignin yield from DES liquor with maximum DES recovery of 95% (w/w). Water distinctly affects the density, viscosity, and intermolecular hydrogen bonding of the DES and its impact on the process dynamics is worth further exploration.
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Affiliation(s)
- Vallari R Chourasia
- Department of Chemical Engineering, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India; Queensland Alliance for Agriculture and Food Innovation, University of Queensland, Brisbane, QLD 4072, Australia
| | - Meena Bisht
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| | - Kamal K Pant
- Department of Chemical Engineering, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India.
| | - Robert J Henry
- Queensland Alliance for Agriculture and Food Innovation, University of Queensland, Brisbane, QLD 4072, Australia
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11
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Lagerman CE, Grover MA, Rousseau RW, Bommarius AS. Reactor Design and Optimization of α-Amino Ester Hydrolase- Catalyzed Synthesis of Cephalexin. Front Bioeng Biotechnol 2022; 10:826357. [PMID: 35309985 PMCID: PMC8924468 DOI: 10.3389/fbioe.2022.826357] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 02/14/2022] [Indexed: 12/04/2022] Open
Abstract
Pharmaceutical production quality has recently been a focus for improvement through incorporation of end-to-end continuous processing. Enzymatic ß-lactam antibiotic synthesis has been one focus for continuous manufacturing, and α-amino ester hydrolases (AEHs) are currently being explored for use in the synthesis of cephalexin due to their high reactivity and selectivity. In this study, several reactors were simulated to determine how reactor type and configuration impacts reactant conversion, fractional yield toward cephalexin, and volumetric productivity for AEH-catalyzed cephalexin synthesis. The primary reactor configurations studied are single reactors including a continuous stirred-tank reactor (CSTR) and plug flow reactor (PFR) as well as two CSTRS and a CSTR + PFR in series. Substrate concentrations fed to the reactors as well as enzyme concentration in the reactor were varied. The presence of substrate inhibition was found to have a negative impact on all reactor configurations studied. No reactor configuration simultaneously allowed high substrate conversion, high fractional yield, and high productivity; however, a single PFR was found to enable the highest substrate conversion with higher fractional yields than all other reactor configurations, by minimizing substrate inhibition. Finally, to further demonstrate the impact of substrate inhibition, an AEH engineered to improve substrate inhibition was simulated and Pareto optimal fronts for a CSTR catalyzed with the current AEH were compared to Pareto fronts for the improved AEH. Overall, reduced substrate inhibition would allow for high substrate conversion, fractional yield, and productivity with only a single CSTR.
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Affiliation(s)
| | | | | | - Andreas S. Bommarius
- School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA, United States
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12
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Kubis MR, Holwerda EK, Lynd LR. Declining carbohydrate solubilization with increasing solids loading during fermentation of cellulosic feedstocks by Clostridium thermocellum: documentation and diagnostic tests. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2022; 15:12. [PMID: 35418299 PMCID: PMC8817502 DOI: 10.1186/s13068-022-02110-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Accepted: 01/15/2022] [Indexed: 12/31/2022]
Abstract
Background For economically viable 2nd generation biofuels, processing of high solid lignocellulosic substrate concentrations is a necessity. The cellulolytic thermophilic anaerobe Clostridium thermocellum is one of the most effective biocatalysts for solubilization of carbohydrate harbored in lignocellulose. This study aims to document the solubilization performance of Clostridium thermocellum at increasing solids concentrations for two lignocellulosic feedstocks, corn stover and switchgrass, and explore potential effectors of solubilization performance. Results Monocultures of Clostridium thermocellum demonstrated high levels of carbohydrate solubilization for both unpretreated corn stover and switchgrass. However, fractional carbohydrate solubilization decreases with increasing solid loadings. Fermentation of model insoluble substrate (cellulose) in the presence of high solids lignocellulosic spent broth is temporarily affected but not model soluble substrate (cellobiose) fermentations. Mid-fermentation addition of cells (C. thermocellum) or model substrates did not significantly enhance overall corn stover solubilization loaded at 80 g/L, however cultures utilized the model substrates in the presence of high concentrations of corn stover. An increase in corn stover solubilization was observed when water was added, effectively diluting the solids concentration mid-fermentation. Introduction of a hemicellulose-utilizing coculture partner, Thermoanaerobacterium thermosaccharolyticum, increased the fractional carbohydrate solubilization at both high and low solid loadings. Residual solubilized carbohydrates diminished significantly in the presence of T. thermosaccharolyticum compared to monocultures of C. thermocellum, yet a small fraction of solubilized oligosaccharides of both C5 and C6 sugars remained unutilized. Conclusion Diminishing fractional carbohydrate solubilization with increasing substrate loading was observed for C. thermocellum-mediated solubilization and fermentation of unpretreated lignocellulose feedstocks. Results of experiments involving spent broth addition do not support a major role for inhibitors present in the liquid phase. Mid-fermentation addition experiments confirm that C. thermocellum and its enzymes remain capable of converting model substrates during the middle of high solids lignocellulose fermentation. An increase in fractional carbohydrate solubilization was made possible by (1) mid-fermentation solid loading dilutions and (2) coculturing C. thermocellum with T. thermosaccharolyticum, which ferments solubilized hemicellulose. Incomplete utilization of solubilized carbohydrates suggests that a small fraction of the carbohydrates is unaffected by the extracellular carbohydrate-active enzymes present in the culture. Supplementary Information The online version contains supplementary material available at 10.1186/s13068-022-02110-4.
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Affiliation(s)
- Matthew R Kubis
- Thayer School of Engineering, Dartmouth College, 14 Engineering Drive, Hanover, NH, 03755, USA.,The Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Evert K Holwerda
- Thayer School of Engineering, Dartmouth College, 14 Engineering Drive, Hanover, NH, 03755, USA. .,The Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.
| | - Lee R Lynd
- Thayer School of Engineering, Dartmouth College, 14 Engineering Drive, Hanover, NH, 03755, USA.,The Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
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13
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Immobilization-Stabilization of β-Glucosidase for Implementation of Intensified Hydrolysis of Cellobiose in Continuous Flow Reactors. Catalysts 2022. [DOI: 10.3390/catal12010080] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Cellulose saccharification to glucose is an operation of paramount importance in the bioenergy sector and the chemical and food industries, while glucose is a critical platform chemical in the integrated biorefinery. Among the cellulose degrading enzymes, β-glucosidases are responsible for cellobiose hydrolysis, the final step in cellulose saccharification, which is usually the critical bottleneck for the whole cellulose saccharification process. The design of very active and stable β-glucosidase-based biocatalysts is a key strategy to implement an efficient saccharification process. Enzyme immobilization and reaction engineering are two fundamental tools for its understanding and implementation. Here, we have designed an immobilized-stabilized solid-supported β-glucosidase based on the glyoxyl immobilization chemistry applied in porous solid particles. The biocatalyst was stable at operational temperature and highly active, which allowed us to implement 25 °C as working temperature with a catalyst productivity of 109 mmol/min/gsupport. Cellobiose degradation was implemented in discontinuous stirred tank reactors, following which a simplified kinetic model was applied to assess the process limitations due to substrate and product inhibition. Finally, the reactive process was driven in a continuous flow fixed-bed reactor, achieving reaction intensification under mild operation conditions, reaching full cellobiose conversion of 34 g/L in a reaction time span of 20 min.
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14
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Medical Waste Treatment Technologies for Energy, Fuels, and Materials Production: A Review. ENERGIES 2021. [DOI: 10.3390/en14238065] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The importance of medical waste management has grown during the COVID-19 pandemic because of the increase in medical waste quantity and the significant dangers of these highly infected wastes for human health and the environment. This innovative review focuses on the possibility of materials, gas/liquid/solid fuels, thermal energy, and electric power production from medical waste fractions. Appropriate and promising treatment/disposal technologies, such as (i) acid hydrolysis, (ii) acid/enzymatic hydrolysis, (iii) anaerobic digestion, (vi) autoclaving, (v) enzymatic oxidation, (vi) hydrothermal carbonization/treatment, (vii) incineration/steam heat recovery system, (viii) pyrolysis/Rankine cycle, (ix) rotary kiln treatment, (x) microwave/steam sterilization, (xi) plasma gasification/melting, (xii) sulfonation, (xiii) batch reactor thermal cracking, and (xiv) torrefaction, were investigated. The medical waste generation data were collected according to numerous researchers from various countries, and divided into gross medical waste and hazardous medical waste. Moreover, the medical wastes were separated into categories and types according to the international literature and the medical waste fractions’ percentages were estimated. The capability of the examined medical waste treatment technologies to produce energy, fuels, and materials, and eliminate the medical waste management problem, was very promising with regard to the near future.
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15
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Dynamic model of simultaneous enzymatic cellulose hydrolysis and product separation in a membrane bioreactor. Biochem Eng J 2021. [DOI: 10.1016/j.bej.2021.108107] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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16
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Conditions of enzyme-assisted extraction to increase the recovery of flavanone aglycones from pectin waste. Journal of Food Science and Technology 2021; 58:4303-4312. [PMID: 34538913 DOI: 10.1007/s13197-020-04906-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Revised: 11/05/2020] [Accepted: 11/13/2020] [Indexed: 10/22/2022]
Abstract
The citrus pectin by-product (CPB), generated from pectin industry, is a rich-source of flavanones, but not explored until now. As most of these compounds are inside vacuoles or bound to cell wall matrix, enzymatic hydrolysis was applied on their recovery, followed by hydroalcoholic and ultrasound extraction. Different parameters were studied: enzymes (β-glucosidase, tannase, and cellulase), their concentration (5, 10, and 20 U g-1 CPB), and reaction time (6, 12, and 24 h). Extracts were characterized in total phenolic content (TPC), antioxidant capacity (ORAC and DPPH assays), and polyphenolic profile (HPLC-DAD). All enzymatic treatments significantly improved CPB antioxidant capacity and TPC, compared with hydroalcoholic and ultrasound extraction. β-glucosidase (5 U) for 24 h was the most effective in polyphenol extraction and bioconversion, followed by β-glucosidase (5 U) for 12 h and tannase (5 U) for 24 h. Thus, the concentration of these enzymes was increased (10 and 20 U) to improve flavanones extraction. β-glucosidase at 20 U offered the highest amount of naringenin (77.63 mg 100 g-1 of CPB) and hesperetin (766.44 mg 100 g-1) obtained so far by biological processes. According to Person's correlation analysis, TPC and antioxidant activity were highly correlated with CPB contents of hesperetin and naringenin. The aglycone flavanones are rarely found in natural sources and have higher biological potential than their glycosylated forms. Our results indicated enzyme-assisted extraction as a good choice for recovering aglycone flavanones from CPB, and increased knowledge on the biological activity of this agroindustrial waste, amplifying their application in food and pharmaceutical field.
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17
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Rahman-Enyart A, Yang W, Yaggie RE, White BA, Welge M, Auvil L, Berry M, Bushell C, Rosen JM, Rudick CN, Schaeffer AJ, Klumpp DJ. Acyloxyacyl hydrolase is a host determinant of gut microbiome-mediated pelvic pain. Am J Physiol Regul Integr Comp Physiol 2021; 321:R396-R412. [PMID: 34318715 PMCID: PMC8530758 DOI: 10.1152/ajpregu.00106.2021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 06/24/2021] [Accepted: 07/16/2021] [Indexed: 12/30/2022]
Abstract
Dysbiosis of gut microbiota is associated with many pathologies, yet host factors modulating microbiota remain unclear. Interstitial cystitis/bladder pain syndrome (IC/BPS) is a debilitating condition of chronic pelvic pain often with comorbid urinary dysfunction and anxiety/depression, and recent studies find fecal dysbiosis in patients with IC/BPS. We identified the locus encoding acyloxyacyl hydrolase, Aoah, as a modulator of pelvic pain severity in a murine IC/BPS model. AOAH-deficient mice spontaneously develop rodent correlates of pelvic pain, increased responses to induced pelvic pain models, voiding dysfunction, and anxious/depressive behaviors. Here, we report that AOAH-deficient mice exhibit dysbiosis of gastrointestinal (GI) microbiota. AOAH-deficient mice exhibit an enlarged cecum, a phenotype long associated with germ-free rodents, and a "leaky gut" phenotype. AOAH-deficient ceca showed altered gene expression consistent with inflammation, Wnt signaling, and urologic disease. 16S sequencing of stool revealed altered microbiota in AOAH-deficient mice, and GC-MS identified altered metabolomes. Cohousing AOAH-deficient mice with wild-type mice resulted in converged microbiota and altered predicted metagenomes. Cohousing also abrogated the pelvic pain phenotype of AOAH-deficient mice, which was corroborated by oral gavage of AOAH-deficient mice with stool slurry of wild-type mice. Converged microbiota also alleviated comorbid anxiety-like behavior in AOAH-deficient mice. Oral gavage of AOAH-deficient mice with anaerobes cultured from IC/BPS stool resulted in exacerbation of pelvic allodynia. Together, these data indicate that AOAH is a host determinant of normal gut microbiota, and dysbiosis associated with AOAH deficiency contributes to pelvic pain. These findings suggest that the gut microbiome is a potential therapeutic target for IC/BPS.
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Affiliation(s)
- Afrida Rahman-Enyart
- Department of Urology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Wenbin Yang
- Division of Thoracic Surgery, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Ryan E Yaggie
- Department of Urology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Bryan A White
- Department of Animal Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois
- National Center for Supercomputing Applications, University of Illinois at Urbana-Champaign, Urbana, Illinois
| | - Michael Welge
- National Center for Supercomputing Applications, University of Illinois at Urbana-Champaign, Urbana, Illinois
| | - Loretta Auvil
- National Center for Supercomputing Applications, University of Illinois at Urbana-Champaign, Urbana, Illinois
| | - Matthew Berry
- National Center for Supercomputing Applications, University of Illinois at Urbana-Champaign, Urbana, Illinois
| | - Colleen Bushell
- National Center for Supercomputing Applications, University of Illinois at Urbana-Champaign, Urbana, Illinois
| | - John M Rosen
- Department of Gastroenterology, Children's Mercy, Kansas City, Missouri
- Department of Pediatrics, University of Missouri, Kansas City, Missouri
| | - Charles N Rudick
- Clinical Pharmacology and Toxicology, Indiana University School of Medicine, Bloomington, Indiana
| | - Anthony J Schaeffer
- Department of Urology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - David J Klumpp
- Department of Urology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
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18
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Mazzei R, Yihdego Gebreyohannes A, Papaioannou E, Nunes SP, Vankelecom IFJ, Giorno L. Enzyme catalysis coupled with artificial membranes towards process intensification in biorefinery- a review. BIORESOURCE TECHNOLOGY 2021; 335:125248. [PMID: 33991878 DOI: 10.1016/j.biortech.2021.125248] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 04/26/2021] [Accepted: 04/28/2021] [Indexed: 06/12/2023]
Abstract
In this review, for the first time, the conjugation of the major types of enzymes used in biorefineries and the membrane processes to develop different configurations of MBRs, was analyzedfor the production of biofuels, phytotherapics and food ingredients. In particular, the aim is to critically review all the works related to the application of MBR in biorefinery, highlighting the advantages and the main drawbacks which can interfere with the development of this system at industrial scale. Alternatives strategies to overcome main limits will be also described in the different application fields, such as the use of biofunctionalized magnetic nanoparticles associated with membrane processes for enzyme re-use and membrane cleaning or the membrane fouling control by the use of integrated membrane process associated with MBR.
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Affiliation(s)
- Rosalinda Mazzei
- Institute on Membrane Technology, National Research Council, ITM-CNR, via P. Bucci, 17/C, I-87030 Rende (Cosenza), Italy.
| | - Abaynesh Yihdego Gebreyohannes
- King Abdullah University of Science and Technology (KAUST), Biological and Environmental Science and Engineering Division (BESE), Advanced Membranes and Porous Materials Center (AMPM), 23955-6900 Thuwal, Saudi Arabia.
| | - Emmaouil Papaioannou
- Engineering Department, Lancaster University, Lancaster, LA1 4YW, United Kingdom
| | - Suzana P Nunes
- King Abdullah University of Science and Technology (KAUST), Biological and Environmental Science and Engineering Division (BESE), Advanced Membranes and Porous Materials Center (AMPM), 23955-6900 Thuwal, Saudi Arabia
| | - Ivo F J Vankelecom
- Membrane Technology Group, Division cMACS, Faculty of Bioscience Engineering, KU Leuven, Celestijnenlaan 200F, PO Box 2454, 3001 Leuven, Belgium
| | - Lidietta Giorno
- Institute on Membrane Technology, National Research Council, ITM-CNR, via P. Bucci, 17/C, I-87030 Rende (Cosenza), Italy
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19
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Zhang Y, Zhang Y, Song M, Topakas E, Yu Q, Yuan Z, Wang Z, Guo Y. Combining Michaelis-Menten theory and enzyme deactivation reactions for the kinetic study of enzymatic hydrolysis by different pretreated sugarcane bagasse. Process Biochem 2021. [DOI: 10.1016/j.procbio.2021.03.023] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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20
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Bioreactor and Bioprocess Design Issues in Enzymatic Hydrolysis of Lignocellulosic Biomass. Catalysts 2021. [DOI: 10.3390/catal11060680] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Saccharification of lignocellulosic biomass is a fundamental step in the biorefinery of second generation feedstock. The physicochemical and enzymatic processes for the depolymerization of biomass into simple sugars has been achieved through numerous studies in several disciplines. The present review discusses the development of technologies for enzymatic saccharification in industrial processes. The kinetics of cellulolytic enzymes involved in polysaccharide hydrolysis has been discussed as the starting point for the design of the most promising bioreactor configurations. The main process configurations—proposed so far—for biomass saccharification have been analyzed. Attention was paid to bioreactor configurations, operating modes and possible integrations of this operation within the biorefinery. The focus is on minimizing the effects of product inhibition on enzymes, maximizing yields and concentration of sugars in the hydrolysate, and reducing the impact of enzyme cost on the whole process. The last part of the review is focused on an emerging process based on the catalytic action of laccase applied to lignin depolymerization as an alternative to the consolidated physicochemical pretreatments. The laccases-based oxidative process has been discussed in terms of characteristics that can affect the development of a bioreactor unit where laccases or a laccase-mediator system can be used for biomass delignification.
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21
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Glasgow EM, Kemna EI, Bingman CA, Ing N, Deng K, Bianchetti CM, Takasuka TE, Northen TR, Fox BG. A structural and kinetic survey of GH5_4 endoglucanases reveals determinants of broad substrate specificity and opportunities for biomass hydrolysis. J Biol Chem 2021; 295:17752-17769. [PMID: 33454012 DOI: 10.1074/jbc.ra120.015328] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 10/15/2020] [Indexed: 11/06/2022] Open
Abstract
Broad-specificity glycoside hydrolases (GHs) contribute to plant biomass hydrolysis by degrading a diverse range of polysaccharides, making them useful catalysts for renewable energy and biocommodity production. Discovery of new GHs with improved kinetic parameters or more tolerant substrate-binding sites could increase the efficiency of renewable bioenergy production even further. GH5 has over 50 subfamilies exhibiting selectivities for reaction with β-(1,4)-linked oligo- and polysaccharides. Among these, subfamily 4 (GH5_4) contains numerous broad-selectivity endoglucanases that hydrolyze cellulose, xyloglucan, and mixed-linkage glucans. We previously surveyed the whole subfamily and found over 100 new broad-specificity endoglucanases, although the structural origins of broad specificity remained unclear. A mechanistic understanding of GH5_4 substrate specificity would help inform the best protein design strategies and the most appropriate industrial application of broad-specificity endoglucanases. Here we report structures of 10 new GH5_4 enzymes from cellulolytic microbes and characterize their substrate selectivity using normalized reducing sugar assays and MS. We found that GH5_4 enzymes have the highest catalytic efficiency for hydrolysis of xyloglucan, glucomannan, and soluble β-glucans, with opportunistic secondary reactions on cellulose, mannan, and xylan. The positions of key aromatic residues determine the overall reaction rate and breadth of substrate tolerance, and they contribute to differences in oligosaccharide cleavage patterns. Our new composite model identifies several critical structural features that confer broad specificity and may be readily engineered into existing industrial enzymes. We demonstrate that GH5_4 endoglucanases can have broad specificity without sacrificing high activity, making them a valuable addition to the biomass deconstruction toolset.
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Affiliation(s)
- Evan M Glasgow
- Department of Biochemistry, University of Wisconsin, Madison, Wisconsin, USA; Great Lakes Bioenergy Research Center, Madison, Wisconsin, USA
| | - Elias I Kemna
- Department of Biochemistry, University of Wisconsin, Madison, Wisconsin, USA
| | - Craig A Bingman
- Department of Biochemistry, University of Wisconsin, Madison, Wisconsin, USA; Great Lakes Bioenergy Research Center, Madison, Wisconsin, USA
| | - Nicole Ing
- Joint BioEnergy Institute, Emeryville, California, USA; Sandia National Laboratories, Livermore, California, USA
| | - Kai Deng
- Joint BioEnergy Institute, Emeryville, California, USA; Sandia National Laboratories, Livermore, California, USA
| | - Christopher M Bianchetti
- Department of Biochemistry, University of Wisconsin, Madison, Wisconsin, USA; Great Lakes Bioenergy Research Center, Madison, Wisconsin, USA
| | | | - Trent R Northen
- Joint BioEnergy Institute, Emeryville, California, USA; Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Brian G Fox
- Department of Biochemistry, University of Wisconsin, Madison, Wisconsin, USA; Great Lakes Bioenergy Research Center, Madison, Wisconsin, USA.
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22
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Summers SR, Alamdari S, Kraft CJ, Brunecky R, Pfaendtner J, Kaar JL. Substitution of distal and active site residues reduces product inhibition of E1 from Acidothermus Cellulolyticus. Protein Eng Des Sel 2021; 34:6476618. [PMID: 34935952 DOI: 10.1093/protein/gzab031] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 09/22/2021] [Accepted: 11/13/2021] [Indexed: 11/14/2022] Open
Abstract
Cellulases are largely afflicted by inhibition from their reaction products, especially at high-substrate loading, which represents a major challenge for biomass processing. This challenge was overcome for endoglucanase 1 (E1) from Acidothermus cellulolyticus by identifying a large conformational change involving distal residues upon binding cellobiose. Having introduced alanine substitutions at each of these residues, we identified several mutations that reduced cellobiose inhibition of E1, including W212A, W213A, Q247A, W249A and F250A. One of the mutations (W212A) resulted in a 47-fold decrease in binding affinity of cellobiose as well as a 5-fold increase in the kcat. The mutation further increased E1 activity on Avicel and dilute-acid treated corn stover and enhanced its productivity at high-substrate loadings. These findings were corroborated by funnel metadynamics, which showed that the W212A substitution led to reduced affinity for cellobiose in the +1 and +2 binding sites due to rearrangement of key cellobiose-binding residues.
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Affiliation(s)
- Samantha R Summers
- Department of Chemical and Biological Engineering, University of Colorado, 3415 Colorado Avenue, Boulder, CO 80309, USA
| | - Sarah Alamdari
- Department of Chemical Engineering, University of Washington, 3781 Okanogan Lane NE, Seattle, WA 98195-1750, USA
| | - Casey J Kraft
- Department of Chemical and Biological Engineering, University of Colorado, 3415 Colorado Avenue, Boulder, CO 80309, USA
| | - Roman Brunecky
- Biosciences Center, National Renewable Energy Lab, 15013 Denver W Pkwy, Golden, CO 80401, USA
| | - Jim Pfaendtner
- Department of Chemical Engineering, University of Washington, 3781 Okanogan Lane NE, Seattle, WA 98195-1750, USA
| | - Joel L Kaar
- Department of Chemical and Biological Engineering, University of Colorado, 3415 Colorado Avenue, Boulder, CO 80309, USA
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23
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Hebal H, Boucherba N, Binay B, Turunen O. Activity and stability of hyperthermostable cellulases and xylanases in ionic liquids. BIOCATAL BIOTRANSFOR 2021. [DOI: 10.1080/10242422.2021.1882430] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Hakim Hebal
- Laboratoire de Microbiologie Appliquée (LMA), Faculté des Sciences de La Nature et de La Vie (FSNV), Université de Bejaia, Bejaia, Algeria
- Faculty of Exact Sciences and Sciences of Nature and Life, Department of Biology, Mohamed Khider University of Biskra, Biskra, Algeria
| | - Nawel Boucherba
- Laboratoire de Microbiologie Appliquée (LMA), Faculté des Sciences de La Nature et de La Vie (FSNV), Université de Bejaia, Bejaia, Algeria
| | - Baris Binay
- Department of Bioengineering, Gebze Technical University, Kocaeli, Turkey
| | - Ossi Turunen
- School of Forest Sciences, University of Eastern Finland, Joensuu, Finland
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Zou G, Bao D, Wang Y, Zhou S, Xiao M, Yang Z, Wang Y, Zhou Z. Alleviating product inhibition of Trichoderma reesei cellulase complex with a product-activated mushroom endoglucanase. BIORESOURCE TECHNOLOGY 2021; 319:124119. [PMID: 32957048 DOI: 10.1016/j.biortech.2020.124119] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 09/08/2020] [Accepted: 09/09/2020] [Indexed: 06/11/2023]
Abstract
Product inhibition of cellulase is a challenging issue in industrial processes. Here, we introduced a product-activated mushroom cellulase, PaCel3A from Polyporus arcularius, into Trichoderma reesei. The filter paper activity, carboxymethyl cellulase activity, and saccharification efficiency (substrate: pretreated rice straw, PRS) of transformants increased significantly with this enzyme (by 18.4-26.8%, 13.8-22.8%, and 17.0%, respectively). A mutant of PaCel3A, PaCel3AM, obtained based on B-factor analysis, saturated mutagenesis, and residual activity assay, showed improved thermostability. The PRS saccharification efficiency using the cellulase complex from T. reesei transformants overexpressing pacel3am increased by 56.4%-63.0%. In addition, the T. reesei cellulase complex obtained by adding the purified recombinant PaCel3AM from T. reesei (rCel3aM-tr) to hydrolyze PRS resulted in increased reducing sugar yields at all sampling points, outperforming the cellulase complexes without rCel3aM-tr. These results suggest that introducing product-activated cellulase genes is a simple and feasible method to alleviate the product inhibition of cellulase.
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Affiliation(s)
- Gen Zou
- Shanghai Key Laboratory of Agricultural Genetics and Breeding; Institute of Edible Fungi, Shanghai Academy of Agriculture Science, 1000 Jinqi Rd, Fengxian 201403, Shanghai, China; CAS-Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Science, Fenglin Rd 300, Shanghai 200032, China.
| | - Dapeng Bao
- Shanghai Key Laboratory of Agricultural Genetics and Breeding; Institute of Edible Fungi, Shanghai Academy of Agriculture Science, 1000 Jinqi Rd, Fengxian 201403, Shanghai, China.
| | - Ying Wang
- Shanghai Key Laboratory of Agricultural Genetics and Breeding; Institute of Edible Fungi, Shanghai Academy of Agriculture Science, 1000 Jinqi Rd, Fengxian 201403, Shanghai, China
| | - Sichi Zhou
- Shanghai Key Laboratory of Agricultural Genetics and Breeding; Institute of Edible Fungi, Shanghai Academy of Agriculture Science, 1000 Jinqi Rd, Fengxian 201403, Shanghai, China
| | - Meili Xiao
- CAS-Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Science, Fenglin Rd 300, Shanghai 200032, China.
| | - Zhanshan Yang
- Shanghai Key Laboratory of Agricultural Genetics and Breeding; Institute of Edible Fungi, Shanghai Academy of Agriculture Science, 1000 Jinqi Rd, Fengxian 201403, Shanghai, China
| | - Yinmei Wang
- CAS-Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Science, Fenglin Rd 300, Shanghai 200032, China.
| | - Zhihua Zhou
- CAS-Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Science, Fenglin Rd 300, Shanghai 200032, China.
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Effect of Severity Factor on the Subcritical Water and Enzymatic Hydrolysis of Coconut Husk for Reducing Sugar Production. BULLETIN OF CHEMICAL REACTION ENGINEERING & CATALYSIS 2020. [DOI: 10.9767/bcrec.15.3.8870.786-797] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Preventing the further degradation of monomeric or oligomeric sugar into by-product during biomass conversion is one of the challenges for fermentable sugar production. In this study, the performance of subcritical water (SCW) and enzymatic hydrolysis of coconut husk toward reducing sugar production was investigated using a severity factor (SF) approach. Furthermore, the optimal condition of SCW was optimized using response surface methodology (RSM), where the composition changes of lignocellulose and sugar yield as responses. From the results, at low SF of SCW, sugar yield escalated as increasing SF value. In the enzymatic hydrolysis process, the effect of SCW pressure is a significant factor enhancing sugar yield. A maximum total sugar yield was attained on the mild SF condition of 2.86. From this work, it was known that the SF approach is sufficient parameter to evaluate the SCW and enzymatic hydrolysis of coconut husk. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).
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Almeida PZD, Oliveira TBD, Lucas RCD, Salgado JCS, Pérez MM, Gálan B, García JL, Polizeli MDLTDM. Heterologous production and biochemical characterization of a new highly glucose tolerant GH1 β-glucosidase from Anoxybacillus thermarum. Process Biochem 2020. [DOI: 10.1016/j.procbio.2020.08.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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Jiménez-Villota DS, Acosta-Pavas JC, Betancur-Ramírez KJ, Ruiz-Colorado AA. Modeling and Kinetic Parameter Estimation of the Enzymatic Hydrolysis Process of Lignocellulosic Materials for Glucose Production. Ind Eng Chem Res 2020. [DOI: 10.1021/acs.iecr.0c03047] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- David Sebastián Jiménez-Villota
- Departamento de Procesos y Energı́a, Facultad de Minas, Universidad Nacional de Colombia—Sede Medellı́n, Medellı́n 050034, Colombia
| | - Juan Camilo Acosta-Pavas
- Departamento de Procesos y Energı́a, Facultad de Minas, Universidad Nacional de Colombia—Sede Medellı́n, Medellı́n 050034, Colombia
| | - Kelly Johana Betancur-Ramírez
- Departamento de Procesos y Energı́a, Facultad de Minas, Universidad Nacional de Colombia—Sede Medellı́n, Medellı́n 050034, Colombia
| | - Angela Adriana Ruiz-Colorado
- Departamento de Procesos y Energı́a, Facultad de Minas, Universidad Nacional de Colombia—Sede Medellı́n, Medellı́n 050034, Colombia
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Du C, Li Y, Zong H, Yuan T, Yuan W, Jiang Y. Production of bioethanol and xylitol from non-detoxified corn cob via a two-stage fermentation strategy. BIORESOURCE TECHNOLOGY 2020; 310:123427. [PMID: 32353769 DOI: 10.1016/j.biortech.2020.123427] [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: 03/13/2020] [Revised: 04/18/2020] [Accepted: 04/20/2020] [Indexed: 06/11/2023]
Abstract
A novel two-stage fermentation strategy was applied to produce xylitol and ethanol from the whole acid-pretreated corn cob slurry. The acid-pretreated corn cob was used without filtration and detoxification by the two-stage fermentation with the robust Kluyveromyces marxianus CICC 1727-5. In the first stage, xylose in the slurry after dilute acid pretreatment of lignocellulosic biomass was used to produce xylitol under micro-aeration conditions. In the second stage, simultaneous saccharification fermentation was carried out, and the ethanol was produced from glucose releasing from the solid. Important parameters, such as aeration rate, cellulase loading during xylose utilization and SSF fermentation were studied for best performance. The two-stage fermentation strategy removed the inhibition of glucose on xylose, and little xylose was left in the fermentation broth. Under the optimized condition, the maximum ethanol and xylitol concentration were 52 g/L and 24.2 g/L corresponding to the yield of 0.41 g/g and 0.82 g/g, respectively.
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Affiliation(s)
- Cong Du
- School of Bioengineering, Dalian University of Technology, Dalia, Liaoning 116024, PR China
| | - Yimin Li
- School of Bioengineering, Dalian University of Technology, Dalia, Liaoning 116024, PR China
| | - Han Zong
- School of Bioengineering, Dalian University of Technology, Dalia, Liaoning 116024, PR China
| | - Tangguo Yuan
- School of Bioengineering, Dalian University of Technology, Dalia, Liaoning 116024, PR China
| | - Wenjie Yuan
- School of Bioengineering, Dalian University of Technology, Dalia, Liaoning 116024, PR China.
| | - Yu Jiang
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA 15261, USA
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Satria H, Yandri, Nurhasanah, Yuwono SD, Herasari D. Extracellular hydrolytic enzyme activities of indigenous actinomycetes on pretreated bagasse using choline acetate ionic liquid. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2020. [DOI: 10.1016/j.bcab.2020.101503] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Peinemann JC, Pleissner D. Continuous pretreatment, hydrolysis, and fermentation of organic residues for the production of biochemicals. BIORESOURCE TECHNOLOGY 2020; 295:122256. [PMID: 31645308 DOI: 10.1016/j.biortech.2019.122256] [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: 09/01/2019] [Revised: 10/08/2019] [Accepted: 10/10/2019] [Indexed: 06/10/2023]
Abstract
Agricultural residues pose a valuable resource. Through microbial fermentations, a variety of products can be obtained, ranging from fuels to platform chemicals. Depending on the nature of the organic residue, pretreatment and hydrolysis are needed prior to fermentation in order to release fermentable sugars. Continuous set-ups are common for the production of methane or ethanol from lignocellulosic biomass, however, this does not apply for the fermentative generation of biochemicals, an approach that conserves chemical functionality present in biomass. Certainly, continuous set-ups could beneficially contribute to bioeconomy by providing techniques allowing the production of biochemicals in a sustainable and efficient way. This review summarizes research conducted on the continuous pretreatment, hydrolysis, and fermentation of lignocellulosic biomass, and particularly towards the production of the biobased molecules: Succinic and lactic acid.
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Affiliation(s)
- Jan Christoph Peinemann
- Sustainable Chemistry (Resource Efficiency), Institute of Sustainable and Environmental Chemistry, Leuphana University of Lüneburg, Universitätsallee 1, C13.203, Lüneburg 21335, Germany
| | - Daniel Pleissner
- Sustainable Chemistry (Resource Efficiency), Institute of Sustainable and Environmental Chemistry, Leuphana University of Lüneburg, Universitätsallee 1, C13.203, Lüneburg 21335, Germany; Institute for Food and Environmental Research e.V., Papendorfer Weg 3, Bad Belzig 14806, Germany.
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Zhao T, Tashiro Y, Sonomoto K. Smart fermentation engineering for butanol production: designed biomass and consolidated bioprocessing systems. Appl Microbiol Biotechnol 2019; 103:9359-9371. [PMID: 31720773 DOI: 10.1007/s00253-019-10198-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2019] [Revised: 10/08/2019] [Accepted: 10/15/2019] [Indexed: 12/18/2022]
Abstract
There is a renewed interest in acetone-butanol-ethanol (ABE) fermentation from renewable substrates for the sustainable and environment-friendly production of biofuel and platform chemicals. However, the ABE fermentation is associated with several challenges due to the presence of heterogeneous components in the renewable substrates and the intrinsic characteristics of ABE fermentation process. Hence, there is a need to select optimal substrates and modify their characteristics suitable for the ABE fermentation process or microbial strain. This "designed biomass" can be used to establish the consolidated bioprocessing systems. As there are very few reports on designed biomass, the main objectives of this review are to summarize the main challenges associated with ABE fermentation from renewable substrates and to introduce feasible strategies for designing the substrates through pretreatment and hydrolysis technologies as well as through the establishment of consolidated bioprocessing systems. This review offers new insights on improving the efficiency of ABE fermentation from designed renewable substrates.
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Affiliation(s)
- Tao Zhao
- Laboratory of Microbial Technology, Division of Systems Bioengineering, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, 744, Motooka, Nishi-ku, Fukuoka, 819-0395, Japan.,Energy-rich Compounds Production by Photosynthetic Carbon Fixation Research Center, College of Life Science, Qingdao Agricultural University, No. 700 Changcheng Road, Chengyang District, Qingdao, 266109, China
| | - Yukihiro Tashiro
- Laboratory of Soil and Environmental Microbiology, Division of Systems Bioengineering, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, 744, Motooka, Nishi-ku, Fukuoka, 819-0395, Japan.,Laboratory of Microbial Environmental Protection, Tropical Microbiology Unit, Center for International Education and Research of Agriculture, Faculty of Agriculture, Kyushu University, 744, Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
| | - Kenji Sonomoto
- Laboratory of Microbial Technology, Division of Systems Bioengineering, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, 744, Motooka, Nishi-ku, Fukuoka, 819-0395, Japan.
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Champreda V, Mhuantong W, Lekakarn H, Bunterngsook B, Kanokratana P, Zhao XQ, Zhang F, Inoue H, Fujii T, Eurwilaichitr L. Designing cellulolytic enzyme systems for biorefinery: From nature to application. J Biosci Bioeng 2019; 128:637-654. [PMID: 31204199 DOI: 10.1016/j.jbiosc.2019.05.007] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Revised: 05/06/2019] [Accepted: 05/11/2019] [Indexed: 12/14/2022]
Abstract
Cellulolytic enzymes play a key role on conversion of lignocellulosic plant biomass to biofuels and biochemicals in sugar platform biorefineries. In this review, we survey composite carbohydrate-active enzymes (CAZymes) among groups of cellulolytic fungi and bacteria that exist under aerobic and anaerobic conditions. Recent advances in designing effective cellulase mixtures are described, starting from the most complex microbial consortium-based enzyme preparations, to single-origin enzymes derived from intensively studied cellulase producers such as Trichoderma reesei, Talaromyces cellulolyticus, and Penicellium funiculosum, and the simplest minimal enzyme systems comprising selected sets of mono-component enzymes tailor-made for specific lignocellulosic substrates. We provide a comprehensive update on studies in developing high-performance cellulases for biorefineries.
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Affiliation(s)
- Verawat Champreda
- National Center for Genetic Engineering and Biotechnology, 113 Thailand Science Park, Phahonyothin Road, Khlong Luang, Pathumthani 12120, Thailand.
| | - Wuttichai Mhuantong
- National Center for Genetic Engineering and Biotechnology, 113 Thailand Science Park, Phahonyothin Road, Khlong Luang, Pathumthani 12120, Thailand
| | - Hataikarn Lekakarn
- Department of Biotechnology, Faculty of Science and Technology, Thammasat University, Rangsit Campus, Phahonyothin Road, Khlong Luang, Pathumthani 12120, Thailand
| | - Benjarat Bunterngsook
- National Center for Genetic Engineering and Biotechnology, 113 Thailand Science Park, Phahonyothin Road, Khlong Luang, Pathumthani 12120, Thailand
| | - Pattanop Kanokratana
- National Center for Genetic Engineering and Biotechnology, 113 Thailand Science Park, Phahonyothin Road, Khlong Luang, Pathumthani 12120, Thailand
| | - Xin-Qing Zhao
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Fei Zhang
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Hiroyuki Inoue
- Research Institute for Sustainable Chemistry, National Institute of Advanced Industrial Science and Technology, 3-11-32 Kagamiyama, Hiroshima 739-0046, Japan
| | - Tatsuya Fujii
- Research Institute for Sustainable Chemistry, National Institute of Advanced Industrial Science and Technology, 3-11-32 Kagamiyama, Hiroshima 739-0046, Japan
| | - Lily Eurwilaichitr
- National Center for Genetic Engineering and Biotechnology, 113 Thailand Science Park, Phahonyothin Road, Khlong Luang, Pathumthani 12120, Thailand
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A Thermostable Aspergillus fumigatus GH7 Endoglucanase Over-Expressed in Pichia pastoris Stimulates Lignocellulosic Biomass Hydrolysis. Int J Mol Sci 2019; 20:ijms20092261. [PMID: 31067833 PMCID: PMC6540056 DOI: 10.3390/ijms20092261] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 04/30/2019] [Accepted: 05/05/2019] [Indexed: 12/15/2022] Open
Abstract
In the context of avoiding the use of non-renewable energy sources, employing lignocellulosic biomass for ethanol production remains a challenge. Cellulases play an important role in this scenario: they are some of the most important industrial enzymes that can hydrolyze lignocellulose. This study aims to improve on the characterization of a thermostable Aspergillus fumigatus endo-1,4-β-glucanase GH7 (Af-EGL7). To this end, Af-EGL7 was successfully expressed in Pichia pastoris X-33. The kinetic parameters Km and Vmax were estimated and suggested a robust enzyme. The recombinant protein was highly stable within an extreme pH range (3.0-8.0) and was highly thermostable at 55 °C for 72 h. Low Cu2+ concentrations (0.1-1.0 mM) stimulated Af-EGL7 activity up to 117%. Af-EGL7 was tolerant to inhibition by products, such as glucose and cellobiose. Glucose at 50 mM did not inhibit Af-EGL7 activity, whereas 50 mM cellobiose inhibited Af-EGL7 activity by just 35%. Additionally, the Celluclast® 1.5L cocktail supplemented with Af-EGL7 provided improved hydrolysis of sugarcane bagasse "in natura", sugarcane exploded bagasse (SEB), corncob, rice straw, and bean straw. In conclusion, the novel characterization of Af-EGL7 conducted in this study highlights the extraordinary properties that make Af-EGL7 a promising candidate for industrial applications.
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Enhancement and modeling of enzymatic hydrolysis on cellulose from agave bagasse hydrothermally pretreated in a horizontal bioreactor. Carbohydr Polym 2019; 211:349-359. [DOI: 10.1016/j.carbpol.2019.01.111] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Revised: 01/29/2019] [Accepted: 01/31/2019] [Indexed: 11/21/2022]
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Nanoengineered cellulosic biohydrogen production via dark fermentation: A novel approach. Biotechnol Adv 2019; 37:107384. [PMID: 31014935 DOI: 10.1016/j.biotechadv.2019.04.006] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Revised: 04/04/2019] [Accepted: 04/16/2019] [Indexed: 02/07/2023]
Abstract
The insights of nanotechnology for cellulosic biohydrogen production through dark fermentation are reviewed. Lignocellulosic biomass to sugar generation is a complex process and covers the most expensive part of cellulose to sugar production technology. In this context, the impacts of nanomaterial on lignocellulosic biomass to biohydrogen production process have been reviewed. In addition, the feasibility of nanomaterials for implementation in each step of the cellulosic biohydrogen production is discussed for economic viability of the process. Numerous aspects such as possible replacement of chemical pretreatment method using nanostructured materials, use of immobilized enzyme for a fast rate of reaction and its reusability along with long viability of microbial cells and hydrogenase enzyme for improving the productivity are the highlights of this review. It is found that various types of nanostructured materials e.g. metallic nanoparticles (Fe°, Ni, Cu, Au, Pd, Au), metal oxide nanoparticles (Fe2O3, F3O4, NiCo2O4, CuO, NiO, CoO, ZnO), nanocomposites (Si@CoFe2O4, Fe3O4/alginate) and graphene-based nanomaterials can influence different parameters of the process and therefore may perhaps be utilized for cellulosic biohydrogen production. The emphasis has been given on the cost issue and synthesis sustainability of nanomaterials for making the biohydrogen technology cost effective. Finally, recent advancements and feasibility of nanomaterials as the potential solution for improved cellulose conversion to the biohydrogen production process have been discussed, and this is likely to assist in developing an efficient, economical and sustainable biohydrogen production technology.
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Zhao T, Yasuda K, Tashiro Y, Darmayanti RF, Sakai K, Sonomoto K. Semi-hydrolysate of paper pulp without pretreatment enables a consolidated fermentation system with in situ product recovery for the production of butanol. BIORESOURCE TECHNOLOGY 2019; 278:57-65. [PMID: 30677699 DOI: 10.1016/j.biortech.2019.01.043] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Revised: 01/08/2019] [Accepted: 01/09/2019] [Indexed: 05/12/2023]
Abstract
Utilization of lignocellulosic biomasses for biobutanol fermentation usually requires costly processes of pretreatment and enzymatic hydrolysis. In this study, paper pulp (93.2% glucan) was used as a starting biomass material to produce biobutanol. We conducted enzymatic semi-hydrolysis of paper pulp without pretreatment and with low enzyme loading, which produced high concentrations of cellobiose (13.9 g L-1) and glucose (21.3 g L-1). In addition, efficient fermentation of the semi-hydrolysate was achieved similar to that with the use of commercial sugars without inhibitors. Finally, we designed a novel non-isothermal simultaneous saccharification and fermentation with in situ butanol recovery, which was composed of a repeated semi-hydrolysis process and successive butanol-extractive fermentation process under the respective optimal conditions. The consolidated system improved butanol production, butanol yields, and butanol productivities and enabled repeated use of medium when compared with other integrated hydrolysis and fermentation processes.
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Affiliation(s)
- Tao Zhao
- Laboratory of Microbial Technology, Division of Systems Bioengineering, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, 744, Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Kento Yasuda
- Laboratory of Microbial Technology, Division of Systems Bioengineering, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, 744, Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Yukihiro Tashiro
- Laboratory of Soil and Environmental Microbiology, Division of Systems Bioengineering, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, 744, Motooka, Nishi-ku, Fukuoka 819-0395, Japan; Laboratory of Microbial Environmental Protection, Tropical Microbiology Unit, Center for International Education and Research of Agriculture, Faculty of Agriculture, Kyushu University, 744, Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Rizki Fitria Darmayanti
- Laboratory of Microbial Technology, Division of Systems Bioengineering, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, 744, Motooka, Nishi-ku, Fukuoka 819-0395, Japan; Department of Chemical Engineering, Faculty of Engineering, University of Jember, Jalan Kalimantan, Kampus Tegal Boto, 68121 Jember, Indonesia
| | - Kenji Sakai
- Laboratory of Soil and Environmental Microbiology, Division of Systems Bioengineering, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, 744, Motooka, Nishi-ku, Fukuoka 819-0395, Japan; Laboratory of Microbial Environmental Protection, Tropical Microbiology Unit, Center for International Education and Research of Agriculture, Faculty of Agriculture, Kyushu University, 744, Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Kenji Sonomoto
- Laboratory of Microbial Technology, Division of Systems Bioengineering, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, 744, Motooka, Nishi-ku, Fukuoka 819-0395, Japan.
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Cai LN, Xu SN, Lu T, Lin DQ, Yao SJ. Directed expression of halophilic and acidophilic β-glucosidases by introducing homologous constitutive expression cassettes in marine Aspergillus niger. J Biotechnol 2019; 292:12-22. [DOI: 10.1016/j.jbiotec.2018.12.015] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Revised: 12/18/2018] [Accepted: 12/29/2018] [Indexed: 01/31/2023]
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Functional characterisation of cellobiohydrolase I (Cbh1) from Trichoderma virens UKM1 expressed in Aspergillus niger. Protein Expr Purif 2019; 154:52-61. [DOI: 10.1016/j.pep.2018.09.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Revised: 08/12/2018] [Accepted: 09/20/2018] [Indexed: 11/20/2022]
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Chen CH, Yao JY, Yang B, Lee HL, Yuan SF, Hsieh HY, Liang PH. Engineer multi-functional cellulase/xylanase/β-glucosidase with improved efficacy to degrade rice straw. ACTA ACUST UNITED AC 2019. [DOI: 10.1016/j.biteb.2019.01.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Kim JK, Yang J, Park SY, Yu JH, Kim KH. Cellulase recycling in high-solids enzymatic hydrolysis of pretreated empty fruit bunches. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:138. [PMID: 31178926 PMCID: PMC6551891 DOI: 10.1186/s13068-019-1476-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Accepted: 05/25/2019] [Indexed: 05/03/2023]
Abstract
BACKGROUND The lignocellulosic biomass feedstocks such as empty fruit bunches (EFBs) prove to be potential renewable resources owing to their abundance, low prices, and high carbohydrate contents. Generally, the conversion of lignocellulosic biomass into chemicals, fuels, and materials mainly includes pretreatment, enzymatic hydrolysis, fermentation, and recovery of final products. To increase the economic viability of such processes, the cost of cellulase production and enzymatic hydrolysis should be reduced. For this, recycling cellulase can be considered for reducing the saccharification cost of lignocellulose. In this study, cellulase recycling for high-solids enzymatic hydrolysis (i.e., 20%) was evaluated in saccharification of hydrothermally-pretreated EFBs. RESULTS High-solids (20%) enzymatic hydrolysis of hydrothermally-pretreated empty fruit bunches with 40 FPU of Cellic CTec3/g glucan was carried out for cellulase recycling. In the second round of hydrolysis using a recycled enzyme, only 19.3% of glucose yield was obtained. The most important limiting factors for cellulase recycling of this study were identified as the enzyme inhibition by glucose, the loss of enzyme activities, and the non-productive binding of enzymes to insoluble biomass solids. To overcome these limitations, PEG was added prior to the first-round hydrolysis to reduce non-productive enzyme binding, glucose was removed from the enzyme fraction to be reused in the second-round hydrolysis, and EFB solids from the first-round hydrolysis were used in the second-round hydrolysis. These three additional measures with cellulase recycling resulted in a 3.5 times higher glucose yield (i.e., 68.0%) at the second round than that of the control, the second-round hydrolysis with cellulase recycling but without these measures. CONCLUSIONS Because of the high obstacles found in this study in achieving high saccharification yields in the high-solids saccharification of high-lignin lignocellulose with cellulase recycling, effective measures for improving enzymatic saccharification yields need to be accompanied with cellulase recycling.
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Affiliation(s)
- Jae Kyun Kim
- Department of Biotechnology, Graduate School, Korea University, Seoul, 02841 South Korea
| | - Jungwoo Yang
- Department of Biotechnology, Graduate School, Korea University, Seoul, 02841 South Korea
| | - So Young Park
- Department of Biotechnology, Graduate School, Korea University, Seoul, 02841 South Korea
| | - Ju-Hyun Yu
- Center for Bio-based Chemical, Green Chemistry and Engineering Division, Korea Research Institute of Chemical Technology, Daejeon, 34602 South Korea
| | - Kyoung Heon Kim
- Department of Biotechnology, Graduate School, Korea University, Seoul, 02841 South Korea
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Kao MR, Kuo HW, Lee CC, Huang KY, Huang TY, Li CW, Chen CW, Wang AHJ, Yu SM, Ho THD. Chaetomella raphigera β-glucosidase D2-BGL has intriguing structural features and a high substrate affinity that renders it an efficient cellulase supplement for lignocellulosic biomass hydrolysis. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:258. [PMID: 31700541 PMCID: PMC6825360 DOI: 10.1186/s13068-019-1599-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Accepted: 10/22/2019] [Indexed: 05/17/2023]
Abstract
BACKGROUND To produce second-generation biofuels, enzymatic catalysis is required to convert cellulose from lignocellulosic biomass into fermentable sugars. β-Glucosidases finalize the process by hydrolyzing cellobiose into glucose, so the efficiency of cellulose hydrolysis largely depends on the quantity and quality of these enzymes used during saccharification. Accordingly, to reduce biofuel production costs, new microbial strains are needed that can produce highly efficient enzymes on a large scale. RESULTS We heterologously expressed the fungal β-glucosidase D2-BGL from a Taiwanese indigenous fungus Chaetomella raphigera in Pichia pastoris for constitutive production by fermentation. Recombinant D2-BGL presented significantly higher substrate affinity than the commercial β-glucosidase Novozyme 188 (N188; K m = 0.2 vs 2.14 mM for p-nitrophenyl β-d-glucopyranoside and 0.96 vs 2.38 mM for cellobiose). When combined with RUT-C30 cellulases, it hydrolyzed acid-pretreated lignocellulosic biomasses more efficiently than the commercial cellulase mixture CTec3. The extent of conversion from cellulose to glucose was 83% for sugarcane bagasse and 63% for rice straws. Compared to N188, use of D2-BGL halved the time necessary to produce maximal levels of ethanol by a semi-simultaneous saccharification and fermentation process. We upscaled production of recombinant D2-BGL to 33.6 U/mL within 15 days using a 1-ton bioreactor. Crystal structure analysis revealed that D2-BGL belongs to glycoside hydrolase (GH) family 3. Removing the N-glycosylation N68 or O-glycosylation T431 residues by site-directed mutagenesis negatively affected enzyme production in P. pastoris. The F256 substrate-binding residue in D2-BGL is located in a shorter loop surrounding the active site pocket relative to that of Aspergillus β-glucosidases, and this short loop is responsible for its high substrate affinity toward cellobiose. CONCLUSIONS D2-BGL is an efficient supplement for lignocellulosic biomass saccharification, and we upscaled production of this enzyme using a 1-ton bioreactor. Enzyme production could be further improved using optimized fermentation, which could reduce biofuel production costs. Our structure analysis of D2-BGL offers new insights into GH3 β-glucosidases, which will be useful for strain improvements via a structure-based mutagenesis approach.
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Affiliation(s)
- Mu-Rong Kao
- Molecular and Cell Biology, Taiwan International Graduate Program, Academia Sinica and National Defense Medical Center, Taipei, Taiwan, ROC
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan, ROC
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan, ROC
| | - Hsion-Wen Kuo
- Department of Environmental Science and Engineering, Tunghai University, Taichung, Taiwan, ROC
| | - Cheng-Chung Lee
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan, ROC
| | - Kuan-Ying Huang
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan, ROC
| | - Ting-Yen Huang
- Department of Bioengineering, Tatung University, Taipei, Taiwan, ROC
| | - Chen-Wei Li
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan, ROC
| | - C. Will Chen
- Department of Bioengineering, Tatung University, Taipei, Taiwan, ROC
| | | | - Su-May Yu
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan, ROC
- Biotechnology Center, National Chung Hsing University, Taichung, Taiwan, ROC
| | - Tuan-Hua David Ho
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan, ROC
- Biotechnology Center, National Chung Hsing University, Taichung, Taiwan, ROC
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Wen P, Zhang T, Wang J, Lian Z, Zhang J. Production of xylooligosaccharides and monosaccharides from poplar by a two-step acetic acid and peroxide/acetic acid pretreatment. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:87. [PMID: 31011370 PMCID: PMC6463647 DOI: 10.1186/s13068-019-1423-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Accepted: 04/03/2019] [Indexed: 05/11/2023]
Abstract
BACKGROUND Populus (poplar) tree species including hybrid varieties are considered as promising biomass feedstock for biofuels and biochemicals production due to their fast growing, short vegetative cycle, and widely distribution. In this work, poplar was pretreated with acetic acid (AC) to produce xylooligosaccharides (XOS), and hydrogen peroxide-acetic acid (HPAC) was used to remove residual lignin in AC-pretreated poplar for enzymatic hydrolysis. The aim of this work is to produce XOS and monosaccharides from poplar by a two-step pretreatment method. RESULTS The optimal conditions for the AC pretreatment were 170 °C, 5% AC, and 30 min, giving a XOS yield of 55.8%. The optimal HPAC pretreatment conditions were 60 °C, 2 h, and 80% HPAC, resulting in 92.7% delignification and 87.8% cellulose retention in the AC-pretreated poplar. The two step-treated poplar presented 86.6% glucose yield and 89.0% xylose yield by enzymatic hydrolysis with a cellulases loading of 7.2 m/g dry mass. Very high glucose (93.8%) and xylose (94.6%) yields were obtained with 14.3 mg cellulases/g dry mass. Both Tween 80 and β-glucosidase enhanced glucose yield of HPAC-pretreated poplar by alleviating the accumulation of cellobiose. Under the optimal conditions, 6.9 g XOS, 40.3 g glucose, and 8.9 g xylose were produced from 100 g poplar. CONCLUSIONS The AC and HPAC pretreatment of poplar represented an efficient strategy to produce XOS and fermentable sugars with high yields. This two-step pretreatment was a recyclable benign and advantageous scheme for biorefinery of the poplar into XOS and monosaccharides.
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Affiliation(s)
- Peiyao Wen
- College of Forestry, Northwest A&F University, 3 Taicheng Road, Yangling, 712100 Shaanxi China
| | - Tian Zhang
- College of Forestry, Northwest A&F University, 3 Taicheng Road, Yangling, 712100 Shaanxi China
| | - Jinye Wang
- College of Forestry, Northwest A&F University, 3 Taicheng Road, Yangling, 712100 Shaanxi China
| | - Zhina Lian
- Co-Innovation Center for Efficient Processing and Utilization of Forest Products, College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037 Jiangsu China
| | - Junhua Zhang
- College of Forestry, Northwest A&F University, 3 Taicheng Road, Yangling, 712100 Shaanxi China
- Co-Innovation Center for Efficient Processing and Utilization of Forest Products, College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037 Jiangsu China
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43
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Qin Z, Luo S, Li Y, Chen Q, Qiu Y, Zhao L, Jiang L, Zhou J. Biochemical properties of a novel chitosanase from Bacillus amyloliquefaciens and its use in membrane reactor. Lebensm Wiss Technol 2018. [DOI: 10.1016/j.lwt.2018.06.027] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Sadraei SI, St Onge B, Trant JF. Recent advances in the application of carbohydrates as renewable feedstocks for the synthesis of nitrogen-containing compounds. PHYSICAL SCIENCES REVIEWS 2018. [DOI: 10.1515/psr-2018-0074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Carbohydrates, in the form of chitin, chitosan and cellulose, are one of the most available, renewable, and sustainable chemical feedstocks. Their conversion to biofuels, fine chemicals, and industrially-relevant monomers is becoming increasingly viable and promising as innovation decreases the price of this technology, and climate change and the price of fossil fuels increases the social and economic costs of using traditional feedstocks. In recent years, carbohydrates have been increasingly used as sources for nitrogen-containing fine chemicals. This chapter, with 86 references, provides a brief overview of the conversion of carbohydrate biomass to the standard hydrocarbon and oxygen-containing derivatives, and then provides a survey of recent progress in converting the biopolymers, and the derived mono and di-saccharides, into nitrogen-containing molecules with a special focus on N-heterocycle synthesis for medicinal applications.
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Affiliation(s)
- S. Iraj Sadraei
- Department of Chemistry and Biochemistry , University of Windsor , 401 Sunset Ave. , Windsor , Ontario N9B 3P4 , Canada
| | - Brent St Onge
- Department of Chemistry and Biochemistry , University of Windsor , 401 Sunset Ave. , Windsor , Ontario N9B 3P4 , Canada
| | - John F. Trant
- Department of Chemistry and Biochemistry , University of Windsor , 401 Sunset Ave. , Windsor , Ontario N9B 3P4 , Canada
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Zhao T, Tashiro Y, Zheng J, Sakai K, Sonomoto K. Semi-hydrolysis with low enzyme loading leads to highly effective butanol fermentation. BIORESOURCE TECHNOLOGY 2018; 264:335-342. [PMID: 29886308 DOI: 10.1016/j.biortech.2018.05.056] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Revised: 05/14/2018] [Accepted: 05/15/2018] [Indexed: 06/08/2023]
Abstract
To improve butanol fermentation efficiencies, semi-hydrolysate with low enzyme loading using H2SO4 pretreated rice straw was designed, which preferably produced cellobiose with xylose (instead of glucose). Fermentation of semi-hydrolysates avoided carbon catabolite repression (CCR) and produced higher butanol yield to enzyme loading (0.0290 g U-1), a newly proposed parameter, than the conventional glucose-oriented hydrolysate (0.00197 g U-1). Further, overall butanol productivity was improved from 0.0628 g L-1 h-1 to 0.265 g L-1 h-1 during fermentation of undetoxified semi-hydrolysate by using high cell density. A novel simultaneously repeated hydrolysis and fermentation (SRHF) was constructed by recycling of enzymes and cells, which further improved butanol yield to enzyme loading by 183% and overall butanol productivity by 6.04%. Thus, semi-hydrolysate with SRHF is a smartly designed biomass for efficient butanol fermentation of lignocellulosic materials.
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Affiliation(s)
- Tao Zhao
- Laboratory of Microbial Technology, Division of Systems Bioengineering, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan
| | - Yukihiro Tashiro
- Laboratory of Soil and Environmental Microbiology, Division of Systems Bioengineering, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan; Laboratory of Microbial Environmental Protection, Tropical Microbiology Unit, Center for International Education and Research of Agriculture, Faculty of Agriculture, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan
| | - Jin Zheng
- State Key Lab of Petroleum Pollution Control, Beijing 102206, China; Research Division of Environment Technology, CNPC Research Institute of Safety & Environmental Technology, Beijing 102206, China
| | - Kenji Sakai
- Laboratory of Soil and Environmental Microbiology, Division of Systems Bioengineering, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan; Laboratory of Microbial Environmental Protection, Tropical Microbiology Unit, Center for International Education and Research of Agriculture, Faculty of Agriculture, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan
| | - Kenji Sonomoto
- Laboratory of Microbial Technology, Division of Systems Bioengineering, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan.
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46
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Gebreyohannes AY, Dharmjeet M, Swusten T, Mertens M, Verspreet J, Verbiest T, Courtin CM, Vankelecom IFJ. Simultaneous glucose production from cellulose and fouling reduction using a magnetic responsive membrane reactor with superparamagnetic nanoparticles carrying cellulolytic enzymes. BIORESOURCE TECHNOLOGY 2018; 263:532-540. [PMID: 29778024 DOI: 10.1016/j.biortech.2018.05.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Revised: 04/27/2018] [Accepted: 05/01/2018] [Indexed: 06/08/2023]
Abstract
This work aimed at investigating simultaneous hydrolysis of cellulose and in-situ foulant degradation in a cellulose fed superparamagnetic biocatalytic membrane reactor (BMRSP). In this reactor, a dynamic layer of superparamagnetic bionanocomposites with immobilized cellulolytic enzymes were reversibly immobilized on superparamagnetic polymeric membrane using an external magnetic field. The formation of a dynamic layer of bionanocomposites on the membrane helped to prevent direct membrane-foulant interaction. Due to in-situ biocatalysis, there was limited filtration resistance. Simultaneous separation of the product helped to avoid enzyme product inhibition, achieve constant reaction rate over time and 50% higher enzyme efficiency than batch reactor. Stable enzyme immobilization and the ability to keep enzyme in the system for long period helped to achieve continuous productivity at very low enzyme but high solid loading, while also reducing the extent of membrane fouling. Hence, the BMRSP paves a path for sustainable production of bioethanol from the cheaply available lignocellulose.
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Affiliation(s)
- Abaynesh Yihdego Gebreyohannes
- Centre for Surface Chemistry and Catalysis KU Leuven Chem & Tech, Celestijnenlaan 200F, Postbus 2461 3001 Leuven, Belgium
| | | | - Tom Swusten
- Molecular Imaging and Photonics, Faculty of Bioengineering Sciences, KU Leuven, Celestijnenlaan 200d - Box 2425, 3001 Leuven, Belgium
| | - Matthias Mertens
- Centre for Surface Chemistry and Catalysis KU Leuven Chem & Tech, Celestijnenlaan 200F, Postbus 2461 3001 Leuven, Belgium
| | - Joran Verspreet
- Laboratory of Food Chemistry and Biochemistry & Leuven Food Science and Nutrition Research Centre (LFoRCe), Faculty of Bioengineering Sciences, KU Leuven, Kasteelpark Arenberg 22, PO Box 2463, 3001 Leuven, Belgium
| | - Thierry Verbiest
- Molecular Imaging and Photonics, Faculty of Bioengineering Sciences, KU Leuven, Celestijnenlaan 200d - Box 2425, 3001 Leuven, Belgium
| | - Christophe M Courtin
- Laboratory of Food Chemistry and Biochemistry & Leuven Food Science and Nutrition Research Centre (LFoRCe), Faculty of Bioengineering Sciences, KU Leuven, Kasteelpark Arenberg 22, PO Box 2463, 3001 Leuven, Belgium
| | - Ivo F J Vankelecom
- Centre for Surface Chemistry and Catalysis KU Leuven Chem & Tech, Celestijnenlaan 200F, Postbus 2461 3001 Leuven, Belgium.
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Dey P, Pal P, Kevin JD, Das DB. Lignocellulosic bioethanol production: prospects of emerging membrane technologies to improve the process – a critical review. REV CHEM ENG 2018. [DOI: 10.1515/revce-2018-0014] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
To meet the worldwide rapid growth of industrialization and population, the demand for the production of bioethanol as an alternative green biofuel is gaining significant prominence. The bioethanol production process is still considered one of the largest energy-consuming processes and is challenging due to the limited effectiveness of conventional pretreatment processes, saccharification processes, and extreme use of electricity in common fermentation and purification processes. Thus, it became necessary to improve the bioethanol production process through reduced energy requirements. Membrane-based separation technologies have already gained attention due to their reduced energy requirements, investment in lower labor costs, lower space requirements, and wide flexibility in operations. For the selective conversion of biomasses to bioethanol, membrane bioreactors are specifically well suited. Advanced membrane-integrated processes can effectively contribute to different stages of bioethanol production processes, including enzymatic saccharification, concentrating feed solutions for fermentation, improving pretreatment processes, and finally purification processes. Advanced membrane-integrated simultaneous saccharification, filtration, and fermentation strategies consisting of ultrafiltration-based enzyme recycle system with nanofiltration-based high-density cell recycle fermentation system or the combination of high-density cell recycle fermentation system with membrane pervaporation or distillation can definitely contribute to the development of the most efficient and economically sustainable second-generation bioethanol production process.
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Affiliation(s)
- Pinaki Dey
- Department of Biotechnology , Karunya Institute of Technology and Sciences , Karunya Nagar Coimbatore 641114 , India
| | - Parimal Pal
- Department of Chemical Engineering , National Institute of Technology , Durgapur , India
| | - Joseph Dilip Kevin
- Department of Biotechnology , Karunya Institute of Technology and Sciences , Coimbatore , India
| | - Diganta Bhusan Das
- Department of Chemical Engineering, School of AACME , Loughborough University , Loughborough, Leicestershire , UK
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48
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Effective lactic acid production from waste paper using Streptococcus thermophilus at low enzyme loading assisted by Gleditsia saponin. Carbohydr Polym 2018; 200:122-127. [PMID: 30177148 DOI: 10.1016/j.carbpol.2018.07.063] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Revised: 07/18/2018] [Accepted: 07/19/2018] [Indexed: 11/23/2022]
Abstract
Waste paper has considerable potential as a raw material for lactic acid (LA) production due to high cellulose content, abundance and low cost. In this study, four kinds of waste papers were used for LA production through simultaneous saccharification and fermentation (SSF) by Streptococcus thermophilus. The SSF of office paper achieved the highest LA concentration (39.71 g/L), while the highest LA yield was observed for magazine (99.56%), followed by office paper (82.85%). High LA concentration is unfavorable to total LA conversion because of product inhibition. However, the addition of Gleditsia saponin (GS) could obtain both high yield and high concentration of LA at a low enzyme loading, indicating that product inhibition could be moderated. A lactic acid yield of 86.30% was obtained from office paper at an enzyme loading of 9 FPU/g-cellulose with GS, which was higher than that of without GS at a higher loading of 18 FPU/g-cellulose.
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49
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Shimizu Y, Sagiya D, Matsui M, Fukui R. Zonal Soil Amendment with Simple Sugars to Elevate Soil C/N Ratios as an Alternative Disease Management Strategy for Rhizoctonia Damping-off of Sugar Beet. PLANT DISEASE 2018; 102:1434-1444. [PMID: 30673559 DOI: 10.1094/pdis-09-16-1279-re] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Effects of monosaccharide-amended soils on suppression of Rhizoctonia damping-off of sugar beet were compared under controlled experiments. Suppressive effects of glucose, fructose, sorbose, and xylose were significantly (P < 0.001) greater than that of galactose or mannose but the effect of sorbose was reduced by soil treatments with antibiotics. Saprotrophic growth of Rhizoctonia solani in the laimosphere also was suppressed by glucose, fructose, sorbose, and xylose, whereas only sorbose repressed pericarp colonization. Sugar alcohols (mannitol, sorbitol, and xylitol) neither suppressed Rhizoctonia damping-off nor halted the saprotrophic growth of the pathogen. Seed germination was not affected by any of these six monosaccharides, whereas galactose and mannose inhibited seedling emergence significantly (P < 0.001) compared with the nontreated control or other monosaccharides. Soil fertilization with inorganic nitrogen at a C/N ratio of 20:1 negated the suppressive effects of glucose and fructose on both damping-off and saprotrophic colonization but improved seedling growth in carbonized soils. Obviously, microbial competition for mineral nitrogen was responsible for disease suppression; however, it delayed seedling growth after emergence. This paradox was resolved by adding glucose to the top 1-cm surface-soil zone at a C/N ratio of 50:1 or 125:1. This protected the laimosphere, resulting in effective disease suppression while complementarily enhancing seedling growth.
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Affiliation(s)
- Yukari Shimizu
- Department of Agrobiology and Biosciences, Utsunomiya University, Utsunomiya, Tochigi, 321-8505, Japan
| | - Daiki Sagiya
- Department of Agrobiology and Biosciences, Utsunomiya University, Utsunomiya, Tochigi, 321-8505, Japan
| | - Mariko Matsui
- Department of Agrobiology and Biosciences, Utsunomiya University, Utsunomiya, Tochigi, 321-8505, Japan
| | - Ryo Fukui
- Department of Agrobiology and Biosciences, Utsunomiya University, Utsunomiya, Tochigi, 321-8505, Japan
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50
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Zhai R, Hu J, Saddler JN. The inhibition of hemicellulosic sugars on cellulose hydrolysis are highly dependant on the cellulase productive binding, processivity, and substrate surface charges. BIORESOURCE TECHNOLOGY 2018; 258:79-87. [PMID: 29524690 DOI: 10.1016/j.biortech.2017.12.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2017] [Revised: 12/02/2017] [Accepted: 12/04/2017] [Indexed: 05/24/2023]
Abstract
In this study, the influence of major hemicellulosic sugars (mannose and xylose) on cellulose hydrolysis and major enzyme activities were evaluated by using both commercial enzyme cocktail and purified cellulase monocomponents over a "library" of cellulosic substrates. Surprisingly, the results showed that unlike glucose, mannose/xylose did not inhibit individual cellulase activities but significantly decreased their hydrolytic performance on cellulose substrates. When various enzyme-substrate interactions (e.g. adsorption/desorption, productive binding, and processive moving) were evaluated, it appeared that these hemicellulosic sugars significantly reduced the productive binding and processivity of Cel7A, which in turn limited cellulase hydrolytic efficacy. Among a range of major cellulose characteristics (e.g. crystallinity, degree of polymerization, accessibility, and surface charges), the acid group content of the cellulosic substrates seemed to be the main driver that determined the extent of hemicellulosic sugar inhibition. Our results provided new insights for better understanding the sugar inhibition mechanisms of cellulose hydrolysis.
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Affiliation(s)
- Rui Zhai
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, 200 Xiaolingwei Street, Nanjing 210094, China; Forest Products Biotechnology and Bioenergy Group, Department of Wood Science, Faculty of Forestry, The University of British Columbia, 2424 Main Mall, Vancouver, BC, Canada
| | - Jinguang Hu
- Forest Products Biotechnology and Bioenergy Group, Department of Wood Science, Faculty of Forestry, The University of British Columbia, 2424 Main Mall, Vancouver, BC, Canada.
| | - Jack N Saddler
- Forest Products Biotechnology and Bioenergy Group, Department of Wood Science, Faculty of Forestry, The University of British Columbia, 2424 Main Mall, Vancouver, BC, Canada
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