1
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Ying W, Zhu J, Xu Y, Zhang J. High solid loading enzymatic hydrolysis of acetic acid-peroxide/acetic acid pretreated poplar and cellulase recycling. BIORESOURCE TECHNOLOGY 2021; 340:125624. [PMID: 34364082 DOI: 10.1016/j.biortech.2021.125624] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 07/15/2021] [Accepted: 07/16/2021] [Indexed: 06/13/2023]
Abstract
High solid loading saccharification is the premise of preparing high-concentration sugar which is beneficial to bioethanol production, but the limited sugar concentration and high enzyme dosage are two challenges. In this work, the glucan-rich acetic acid-hydrogen peroxide/acetic acid (AC-HPAC)-pretreated poplar (85.8%) were prepared for enzymatic hydrolysis at 10%-40% solid loading and the strategies for reducing cellulase dosage were explored. Results showed that the maximum glucose concentration reached to 250.8 g/L at 40% solid loading, which was the highest concentration in previous literatures. As the solid loading was 20%, the addition of Tween 80 saved 50% of cellulase and the recycling of unhydrolyzed residue (0.2 g/g DM) saved another 25% of cellulase, resulting in 152.2 g/L of glucose concentration with yield of 79.9%. This work showed potential of poplar to produce the high concentration glucose solution with low enzyme loading through the recycling of enzyme bound onto unhydrolyzed residue.
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Affiliation(s)
- Wenjun Ying
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China
| | - Junjun Zhu
- 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
| | - Yong Xu
- 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
| | - 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; College of Forestry, Northwest A&F University, Yangling 712100, China.
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2
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Strategies towards Reduction of Cellulases Consumption: Debottlenecking the Economics of Lignocellulosics Valorization Processes. POLYSACCHARIDES 2021. [DOI: 10.3390/polysaccharides2020020] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Lignocellulosic residues have been receiving growing interest as a promising source of polysaccharides, which can be converted into a variety of compounds, ranging from biofuels to bioplastics. Most of these can replace equivalent products traditionally originated from petroleum, hence representing an important environmental advantage. Lignocellulosic materials are theoretically unlimited, cheaper and may not compete with food crops. However, the conversion of these materials to simpler sugars usually requires cellulolytic enzymes. Being still associated with a high cost of production, cellulases are commonly considered as one of the main obstacles in the economic valorization of lignocellulosics. This work provides a brief overview of some of the most studied strategies that can allow an important reduction of cellulases consumption, hence improving the economy of lignocellulosics conversion. Cellulases recycling is initially discussed regarding the main processes to recover active enzymes and the most important factors that may affect enzyme recyclability. Similarly, the potential of enzyme immobilization is analyzed with a special focus on the contributions that some elements of the process can offer for prolonged times of operation and improved enzyme stability and robustness. Finally, the emergent concept of consolidated bioprocessing (CBP) is also described in the particular context of a potential reduction of cellulases consumption.
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3
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Jampana SR, Jia L, Ramarao BV, Kumar D. Experimental investigation of the adsorption and desorption of cellulase enzymes on zeolite-β for enzyme recycling applications. Bioprocess Biosyst Eng 2020; 44:495-505. [PMID: 33067668 DOI: 10.1007/s00449-020-02459-6] [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: 05/13/2020] [Accepted: 09/30/2020] [Indexed: 11/24/2022]
Abstract
The recyclability of cellulase enzymes using zeolite and polyethylene glycol (PEG) was investigated. The cellulase enzymes from cellulose hydrolysate suspensions were adsorbed onto zeolite-β under typical working conditions (pH 5). PEG having a molecular weight of 200 Da and 20 kDa was used as an eluent to desorb the cellulase enzymes from zeolite-β. Adsorption and desorption profiles of cellulase enzymes were studied by varying pH, PEG concentration, and salt concentration. Maximum binding capacity, qm of the zeolite decreased by increasing the pH, or by introducing PEG. At pH 5, the qm of the zeolite was determined to be 121 × 10-3 g/g. About 24%, 51% and 75% of the adsorbed enzyme can be recovered using 1 M NaCl, PEG 200 and PEG 20000, respectively. The specific activity of the recovered enzyme increased by 57% due to the presence of residual PEG.
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Affiliation(s)
- Surya R Jampana
- Department of Chemical Engineering, SUNY College of Environmental Science and Forestry, SYRACUSE, New York, NY, 13210, USA
| | - Linjing Jia
- Department of Chemical Engineering, SUNY College of Environmental Science and Forestry, SYRACUSE, New York, NY, 13210, USA
| | - Bandaru V Ramarao
- Department of Chemical Engineering, SUNY College of Environmental Science and Forestry, SYRACUSE, New York, NY, 13210, USA.
| | - Deepak Kumar
- Department of Chemical Engineering, SUNY College of Environmental Science and Forestry, SYRACUSE, New York, NY, 13210, USA
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4
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Østby H, Hansen LD, Horn SJ, Eijsink VGH, Várnai A. Enzymatic processing of lignocellulosic biomass: principles, recent advances and perspectives. J Ind Microbiol Biotechnol 2020; 47:623-657. [PMID: 32840713 PMCID: PMC7658087 DOI: 10.1007/s10295-020-02301-8] [Citation(s) in RCA: 63] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Accepted: 07/30/2020] [Indexed: 02/06/2023]
Abstract
Efficient saccharification of lignocellulosic biomass requires concerted development of a pretreatment method, an enzyme cocktail and an enzymatic process, all of which are adapted to the feedstock. Recent years have shown great progress in most aspects of the overall process. In particular, increased insights into the contributions of a wide variety of cellulolytic and hemicellulolytic enzymes have improved the enzymatic processing step and brought down costs. Here, we review major pretreatment technologies and different enzyme process setups and present an in-depth discussion of the various enzyme types that are currently in use. We pay ample attention to the role of the recently discovered lytic polysaccharide monooxygenases (LPMOs), which have led to renewed interest in the role of redox enzyme systems in lignocellulose processing. Better understanding of the interplay between the various enzyme types, as they may occur in a commercial enzyme cocktail, is likely key to further process improvements.
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Affiliation(s)
- Heidi Østby
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), P.O. Box 5003, 1432, Aas, Norway
| | - Line Degn Hansen
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), P.O. Box 5003, 1432, Aas, Norway
| | - Svein J Horn
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), P.O. Box 5003, 1432, Aas, Norway
| | - Vincent G H Eijsink
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), P.O. Box 5003, 1432, Aas, Norway
| | - Anikó Várnai
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), P.O. Box 5003, 1432, Aas, Norway.
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5
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Michelin M, Gomes DG, Romaní A, Polizeli MDLTM, Teixeira JA. Nanocellulose Production: Exploring the Enzymatic Route and Residues of Pulp and Paper Industry. Molecules 2020; 25:E3411. [PMID: 32731405 PMCID: PMC7436152 DOI: 10.3390/molecules25153411] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 07/19/2020] [Accepted: 07/23/2020] [Indexed: 12/28/2022] Open
Abstract
Increasing environmental and sustainability concerns, caused by current population growth, has promoted a raising utilization of renewable bio-resources for the production of materials and energy. Recently, nanocellulose (NC) has been receiving great attention due to its many attractive features such as non-toxic nature, biocompatibility, and biodegradability, associated with its mechanical properties and those related to its nanoscale, emerging as a promising material in many sectors, namely packaging, regenerative medicine, and electronics, among others. Nanofibers and nanocrystals, derived from cellulose sources, have been mainly produced by mechanical and chemical treatments; however, the use of cellulases to obtain NC attracted much attention due to their environmentally friendly character. This review presents an overview of general concepts in NC production. Especial emphasis is given to enzymatic hydrolysis processes using cellulases and the utilization of pulp and paper industry residues. Integrated process for the production of NC and other high-value products through enzymatic hydrolysis is also approached. Major challenges found in this context are discussed along with its properties, potential application, and future perspectives of the use of enzymatic hydrolysis as a pretreatment in the scale-up of NC production.
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Affiliation(s)
- Michele Michelin
- CEB—Centre of Biological Engineering, Universidade do Minho, Campus Gualtar, 4710-057 Braga, Portugal; (M.M.); (A.R.); (J.A.T.)
| | - Daniel G. Gomes
- CEB—Centre of Biological Engineering, Universidade do Minho, Campus Gualtar, 4710-057 Braga, Portugal; (M.M.); (A.R.); (J.A.T.)
| | - Aloia Romaní
- CEB—Centre of Biological Engineering, Universidade do Minho, Campus Gualtar, 4710-057 Braga, Portugal; (M.M.); (A.R.); (J.A.T.)
| | - Maria de Lourdes T. M. Polizeli
- Department of Biology, Faculdade de Filosofia Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto SP 14040-901, Brazil;
| | - José A. Teixeira
- CEB—Centre of Biological Engineering, Universidade do Minho, Campus Gualtar, 4710-057 Braga, Portugal; (M.M.); (A.R.); (J.A.T.)
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Cai C, Bao Y, Li F, Pang Y, Lou H, Qian Y, Qiu X. Using highly recyclable sodium caseinate to enhance lignocellulosic hydrolysis and cellulase recovery. BIORESOURCE TECHNOLOGY 2020; 304:122974. [PMID: 32062498 DOI: 10.1016/j.biortech.2020.122974] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Revised: 02/04/2020] [Accepted: 02/05/2020] [Indexed: 06/10/2023]
Abstract
Most additives that capable of enhancing enzymatic hydrolysis of lignocellulose are petroleum-based, which are not easy to recycle with poor biodegradability. In this work, highly recyclable and biodegradable sodium caseinate (SC) was used to enhance lignocellulosic hydrolysis with improved cellulase recyclability. When the pH decreased from 5.5 to 4.8, more than 96% SC could be precipitated from the solution and recovered. Adding SC increased enzymatic digestibility of dilute acid pretreated eucalyptus (Eu-DA) from 39.5% to 78.2% under Eu-DA loading of 10 wt% and pH = 5.5, and increase cellulase content in 72 h hydrolysate from only 15.2% of the original to 60.0%, which facilitated the recovery of cellulases through re-adsorption by fresh substrates. With multiple cycles of re-adsorption, application of SC not only increased the sugar yield of Eu-DA by 95.5%, but also reduced cellulase loading by 40%.
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Affiliation(s)
- Cheng Cai
- School of Chemistry and Chemical Engineering, Guangdong Provincial Engineering Research Center for Green Fine Chemicals, South China University of Technology, Guangzhou, China
| | - Yu Bao
- School of Chemistry and Chemical Engineering, Guangdong Provincial Engineering Research Center for Green Fine Chemicals, South China University of Technology, Guangzhou, China
| | - Feiyun Li
- School of Chemistry and Chemical Engineering, Guangdong Provincial Engineering Research Center for Green Fine Chemicals, South China University of Technology, Guangzhou, China
| | - Yuxia Pang
- School of Chemistry and Chemical Engineering, Guangdong Provincial Engineering Research Center for Green Fine Chemicals, South China University of Technology, Guangzhou, China
| | - Hongming Lou
- School of Chemistry and Chemical Engineering, Guangdong Provincial Engineering Research Center for Green Fine Chemicals, South China University of Technology, Guangzhou, China; State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou, China.
| | - Yong Qian
- School of Chemistry and Chemical Engineering, Guangdong Provincial Engineering Research Center for Green Fine Chemicals, South China University of Technology, Guangzhou, China
| | - Xueqing Qiu
- School of Chemistry and Chemical Engineering, Guangdong Provincial Engineering Research Center for Green Fine Chemicals, South China University of Technology, Guangzhou, China; State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou, China; School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou, China.
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7
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Mou H, Huang J, Li W, Wu X, Liu Y, Fan H. Study on the chemical modification of alkali lignin towards for cellulase adsorbent application. Int J Biol Macromol 2020; 149:794-800. [PMID: 31982529 DOI: 10.1016/j.ijbiomac.2020.01.229] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2019] [Revised: 01/13/2020] [Accepted: 01/22/2020] [Indexed: 11/15/2022]
Abstract
The research of cost-efficient lignin-based adsorbents is a practical strategy for the recovery of cellulase. In this study, alkali lignin was modified to increase the phenolic hydroxyl (Ph-OH) content for cellulase adsorption applications. After phenolation, compared with the lignin reference, the maximum adsorption cellulase capacity of lignoresorcinol (LigR) and lignopyrogallol (LigP) was improved from 76.5 mg/g to 842.1 mg/g and 911.4 mg/g, respectively. The enzyme activity of the adsorbed cellulase on LigR was higher than that on LigP, which could migrate to the fresh substrates during enzymatic hydrolysis. The adsorbed cellulase could be easily recovered from two lignin-based adsorbents by adjusting pH. The distinct cellulase adsorption behavior of two lignin-based adsorbents was closely related to the high Ph-OH contents and low S/G ratio in phenolated lignin samples characterized by Fourier Transform Infrared Spectroscopy (FTIR) and Heteronuclear Single Quantum Coherence-Nuclear Magnetic Resonance (HSQC-NMR).
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Affiliation(s)
- Hongyan Mou
- State Key Laboratory of Pulp and Papermaking, School of Light Industry and Engineering, South China University of Technology, China.
| | - Jin Huang
- State Key Laboratory of Pulp and Papermaking, School of Light Industry and Engineering, South China University of Technology, China
| | - Weiying Li
- State Key Laboratory of Pulp and Papermaking, School of Light Industry and Engineering, South China University of Technology, China
| | - Xiao Wu
- State Key Laboratory of Pulp and Papermaking, School of Light Industry and Engineering, South China University of Technology, China
| | - Yibei Liu
- State Key Laboratory of Pulp and Papermaking, School of Light Industry and Engineering, South China University of Technology, China
| | - Huiming Fan
- State Key Laboratory of Pulp and Papermaking, School of Light Industry and Engineering, South China University of Technology, China
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8
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Wang X, Zeng J, Gao W, Chen K, Wang B, Xu J. Endoglucanase recycling for disintegrating cellulosic fibers to fibrils. Carbohydr Polym 2019; 223:115052. [DOI: 10.1016/j.carbpol.2019.115052] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Accepted: 07/02/2019] [Indexed: 10/26/2022]
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9
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Parnthong J, Kungsanant S, Chavadej S. The Influence of Nonionic Surfactant Adsorption on Enzymatic Hydrolysis of Oil Palm Fruit Bunch. Appl Biochem Biotechnol 2018; 186:895-908. [DOI: 10.1007/s12010-018-2783-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Accepted: 05/11/2018] [Indexed: 10/16/2022]
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10
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Operational Strategies for Enzymatic Hydrolysis in a Biorefinery. BIOFUEL AND BIOREFINERY TECHNOLOGIES 2018. [DOI: 10.1007/978-3-319-67678-4_10] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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11
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Organosolv Fractionation of Softwood Biomass for Biofuel and Biorefinery Applications. ENERGIES 2017. [DOI: 10.3390/en11010050] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Softwoods represent a significant fraction of the available lignocellulosic biomass for conversion into a variety of bio-based products. Its inherent recalcitrance, however, makes its successful utilization an ongoing challenge. In the current work the research efforts for the fractionation and utilization of softwood biomass with the organosolv process are reviewed. A short introduction into the specific challenges of softwood utilization, the development of the biorefinery concept, as well as the initial efforts for the development of organosolv as a pulping method is also provided for better understanding of the related research framework. The effect of organosolv pretreatment at various conditions, in the fractionation efficiency of wood components, enzymatic hydrolysis and bioethanol production yields is then discussed. Specific attention is given in the effect of the pretreated biomass properties such as residual lignin on enzymatic hydrolysis. Finally, the valorization of organosolv lignin via the production of biofuels, chemicals, and materials is also described.
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12
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Loman AA, Islam SMM, Li Q, Ju LK. Enzyme recycle and fed-batch addition for high-productivity soybean flour processing to produce enriched soy protein and concentrated hydrolysate of fermentable sugars. BIORESOURCE TECHNOLOGY 2017; 241:252-261. [PMID: 28575788 DOI: 10.1016/j.biortech.2017.05.118] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Revised: 05/17/2017] [Accepted: 05/18/2017] [Indexed: 06/07/2023]
Abstract
Despite having high protein and carbohydrate, soybean flour utilization is limited to partial replacement of animal feed to date. Enzymatic process can be exploited to increase its value by enriching protein content and separating carbohydrate for utilization as fermentation feedstock. Enzyme hydrolysis with fed-batch and recycle designs were evaluated here for achieving this goal with high productivities. Fed-batch process improved carbohydrate conversion, particularly at high substrate loadings of 250-375g/L. In recycle process, hydrolysate retained a significant portion of the limiting enzyme α-galactosidase to accelerate carbohydrate monomerization rate. At single-pass retention time of 6h and recycle rate of 62.5%, reducing sugar concentration reached up to 120g/L using 4ml/g enzyme. When compared with batch and fed-batch processes, the recycle process increased the volumetric productivity of reducing sugar by 36% (vs. fed-batch) to 57% (vs. batch) and that of protein product by 280% (vs. fed-batch) to 300% (vs. batch).
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Affiliation(s)
- Abdullah Al Loman
- Department of Chemical and Biomolecular Engineering, The University of Akron, Akron, OH 44325-3906, USA
| | - S M Mahfuzul Islam
- Department of Chemical and Biomolecular Engineering, The University of Akron, Akron, OH 44325-3906, USA
| | - Qian Li
- Department of Chemical and Biomolecular Engineering, The University of Akron, Akron, OH 44325-3906, USA
| | - Lu-Kwang Ju
- Department of Chemical and Biomolecular Engineering, The University of Akron, Akron, OH 44325-3906, USA.
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13
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Huang R, Guo H, Su R, Qi W, He Z. Enhanced cellulase recovery without β-glucosidase supplementation for cellulosic ethanol production using an engineered strain and surfactant. Biotechnol Bioeng 2016; 114:543-551. [DOI: 10.1002/bit.26194] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Revised: 08/30/2016] [Accepted: 09/26/2016] [Indexed: 11/10/2022]
Affiliation(s)
- Renliang Huang
- Tianjin Engineering Center of Bio Gas/Oil Technology; School of Environmental Science and Engineering; Tianjin University; Tianjin China
| | - Hong Guo
- State Key Laboratory of Chemical Engineering; School of Chemical Engineering and Technology; Tianjin University; Tianjin 300072 China
| | - Rongxin Su
- State Key Laboratory of Chemical Engineering; School of Chemical Engineering and Technology; Tianjin University; Tianjin 300072 China
- Tianjin Key Laboratory of Membrane Science and Desalination Technology; Tianjin University; Tianjin China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin); Tianjin China
| | - Wei Qi
- State Key Laboratory of Chemical Engineering; School of Chemical Engineering and Technology; Tianjin University; Tianjin 300072 China
- Tianjin Key Laboratory of Membrane Science and Desalination Technology; Tianjin University; Tianjin China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin); Tianjin China
| | - Zhimin He
- State Key Laboratory of Chemical Engineering; School of Chemical Engineering and Technology; Tianjin University; Tianjin 300072 China
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14
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Mesa L, González E, Cara C, Castro E, Mussatto SI. An approach to cellulase recovery from enzymatic hydrolysis of pretreated sugarcane bagasse with high lignin content. BIOCATAL BIOTRANSFOR 2016. [DOI: 10.3109/10242422.2016.1168816] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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15
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Enhanced enzymatic hydrolysis of mild alkali pre-treated rice straw at high-solid loadings using in-house cellulases in a bench scale system. Bioprocess Biosyst Eng 2016; 39:993-1003. [DOI: 10.1007/s00449-016-1578-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Accepted: 02/19/2016] [Indexed: 10/22/2022]
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16
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Rodrigues AC, Haven MØ, Lindedam J, Felby C, Gama M. Celluclast and Cellic® CTec2: Saccharification/fermentation of wheat straw, solid–liquid partition and potential of enzyme recycling by alkaline washing. Enzyme Microb Technol 2015; 79-80:70-7. [DOI: 10.1016/j.enzmictec.2015.06.019] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Revised: 06/14/2015] [Accepted: 06/23/2015] [Indexed: 10/23/2022]
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17
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Samaratunga A, Kudina O, Nahar N, Zakharchenko A, Minko S, Voronov A, Pryor SW. Modeling the Effect of pH and Temperature for Cellulases Immobilized on Enzymogel Nanoparticles. Appl Biochem Biotechnol 2015; 176:1114-30. [DOI: 10.1007/s12010-015-1633-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Accepted: 04/20/2015] [Indexed: 11/28/2022]
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18
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Gomes D, Rodrigues AC, Domingues L, Gama M. Cellulase recycling in biorefineries—is it possible? Appl Microbiol Biotechnol 2015; 99:4131-43. [DOI: 10.1007/s00253-015-6535-z] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Revised: 03/09/2015] [Accepted: 03/11/2015] [Indexed: 11/28/2022]
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19
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Guo H, Zou S, Liu B, Su R, Huang R, Qi W, Zhang M, He Z. Reducing β-glucosidase supplementation during cellulase recovery using engineered strain for successive lignocellulose bioconversion. BIORESOURCE TECHNOLOGY 2015; 187:362-368. [PMID: 25863900 DOI: 10.1016/j.biortech.2015.03.105] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2015] [Revised: 03/21/2015] [Accepted: 03/23/2015] [Indexed: 06/04/2023]
Abstract
Enzyme recycling by re-adsorption is one of the primary methods for reducing enzyme usage in lignocellulose conversion. This work proposes the combination of an engineered yeast strain that expresses β-glucosidase with enzyme recycling to reduce the amount of supplemented β-glucosidase in enzyme recycling experiments. Using the engineered strain, a slight increase in ethanol concentration was obtained after a 96-h fermentation of pretreated corncobs. Ethanol concentrations increased by 34.7% and 62.7% in the following two recycle rounds using the engineered strain compared with those using its parental strain without β-glucosidase addition. Furthermore, with the addition of β-glucosidase at 30CBU/g cellulose, the ethanol concentration after two recycle rounds exceeded 90% of that observed in the first SSF round with the engineered strain at a high initial cellulase loading of 45FPU/g cellulose.
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Affiliation(s)
- Hong Guo
- State Key Laboratory of Chemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
| | - Shaolan Zou
- Tianjin R&D Center for Petrochemical Technology, Tianjin University, Tianjin 300072, China
| | - Boshi Liu
- State Key Laboratory of Chemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
| | - Rongxin Su
- State Key Laboratory of Chemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China; Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, China.
| | - Renliang Huang
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Wei Qi
- State Key Laboratory of Chemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China; Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, China
| | - Minhua Zhang
- Tianjin R&D Center for Petrochemical Technology, Tianjin University, Tianjin 300072, China; Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, China.
| | - Zhimin He
- State Key Laboratory of Chemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
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20
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Bhalla A, Bischoff KM, Sani RK. Highly thermostable GH39 β-xylosidase from a Geobacillus sp. strain WSUCF1. BMC Biotechnol 2014; 14:963. [PMID: 25532585 PMCID: PMC4300165 DOI: 10.1186/s12896-014-0106-8] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Accepted: 12/01/2014] [Indexed: 11/10/2022] Open
Abstract
Background Complete enzymatic hydrolysis of xylan to xylose requires the action of endoxylanase and β-xylosidase. β-xylosidases play an important part in hydrolyzing xylo-oligosaccharides to xylose. Thermostable β-xylosidases have been a focus of attention as industrially important enzymes due to their long shelf life and role in the relief of end-product inhibition of xylanases caused by xylo-oligosaccharides. Therefore, a highly thermostable β-xylosidase with high specific activity has significant potential in lignocellulose bioconversion. Results A gene encoding a highly thermostable GH39 β-xylosidase was cloned from Geobacillus sp. strain WSUCF1 and expressed in Escherichia coli. Recombinant β-xylosidase was active over a wide range of temperatures and pH with optimum temperature of 70°C and pH 6.5. It exhibited very high thermostability, retaining 50% activity at 70°C after 9 days. WSUCF1 β-xylosidase is more thermostable than β-xylosidases reported from other thermophiles (growth temperature ≤ 70°C). Specific activity was 133 U/mg when incubated with p-nitrophenyl xylopyranoside, with Km and Vmax values of 2.38 mM and 147 U/mg, respectively. SDS-PAGE analysis indicated that the recombinant enzyme had a mass of 58 kDa, but omitting heating prior to electrophoresis increased the apparent mass to 230 kDa, suggesting the enzyme exists as a tetramer. Enzyme exhibited high tolerance to xylose, retained approximately 70% of relative activity at 210 mM xylose concentration. Thin layer chromatography showed that the enzyme had potential to convert xylo-oligomers (xylobiose, triose, tetraose, and pentaose) into fermentable xylose. WSUCF1 β-xylosidase along with WSUCF1 endo-xylanase synergistically converted the xylan into fermentable xylose with more than 90% conversion. Conclusions Properties of the WSUCF1 β-xylosidase i.e. high tolerance to elevated temperatures, high specific activity, conversion of xylo-oligomers to xylose, and resistance to inhibition from xylose, make this enzyme potentially suitable for various biotechnological applications.
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Affiliation(s)
- Aditya Bhalla
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, SD, 57701, USA. .,Present address: Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI, 48824, USA.
| | - Kenneth M Bischoff
- Renewable Product Technology Research Unit, Agricultural Research Service, National Center for Agricultural Utilization Research, U.S. Department of Agriculture, Peoria, IL, 61604, USA.
| | - Rajesh K Sani
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, SD, 57701, USA.
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21
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Tsai CT, Meyer AS. Enzymatic cellulose hydrolysis: enzyme reusability and visualization of β-glucosidase immobilized in calcium alginate. Molecules 2014; 19:19390-406. [PMID: 25429563 PMCID: PMC6271082 DOI: 10.3390/molecules191219390] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Revised: 11/15/2014] [Accepted: 11/17/2014] [Indexed: 11/16/2022] Open
Abstract
The high cellulase enzyme dosages required for hydrolysis of cellulose is a major cost challenge in lignocellulosic ethanol production. One method to decrease the enzyme dosage and increase biocatalytic productivity is to re-use β-glucosidase (BG) via immobilization. In the present research, glutaraldehyde cross-linked BG was entrapped in calcium alginate gel particles. More than 60% of the enzyme activity could be recovered under optimized conditions, and glutaraldehyde cross-linking decreased leakage of BG from the calcium alginate particles. The immobilized BG aggregates were visualized by confocal laser scanning microscopy (CLSM). The CLSM images, which we believe are the first to be published, corroborate that more BG aggregates were entrapped in the matrix when the enzymes were cross-linked by glutaraldehyde as opposed to when they are not cross-linked. The particles with the immobilized BG were recycled for cellulase catalyzed hydrolysis of Avicel. No significant loss in BG activity was observed for up to 20 rounds of reaction recycle steps of the BG particles of 48 h each, verifying a significant stabilization of the BG by immobilization. Similar high glucose yields were obtained by one round of enzymatic hydrolysis of hydrothermally pretreated barley straw during a 72 h reaction with immobilized BG and free BG.
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Affiliation(s)
- Chien-Tai Tsai
- Center for Bioprocess Engineering, Department of Chemical and Biochemical Engineering, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark.
| | - Anne S Meyer
- Center for Bioprocess Engineering, Department of Chemical and Biochemical Engineering, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark.
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22
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Chu Q, Li X, Xu Y, Wang Z, Huang J, Yu S, Yong Q. Functional cello-oligosaccharides production from the corncob residues of xylo-oligosaccharides manufacture. Process Biochem 2014. [DOI: 10.1016/j.procbio.2014.05.007] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Carbohydrate-binding modules of fungal cellulases: occurrence in nature, function, and relevance in industrial biomass conversion. ADVANCES IN APPLIED MICROBIOLOGY 2014; 88:103-65. [PMID: 24767427 DOI: 10.1016/b978-0-12-800260-5.00004-8] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
In this review, the present knowledge on the occurrence of cellulases, with a special emphasis on the presence of carbohydrate-binding modules (CBMs) in various fungal strains, has been summarized. The importance of efficient fungal cellulases is growing due to their potential uses in biorefinery processes where lignocellulosic biomasses are converted to platform sugars and further to biofuels and chemicals. Most secreted cellulases studied in detail have a bimodular structure containing an active core domain attached to a CBM. CBMs are traditionally been considered as essential parts in cellulases, especially in cellobiohydrolases. However, presently available genome data indicate that many cellulases lack the binding domains in cellulose-degrading organisms. Recent data also demonstrate that CBMs are not necessary for the action of cellulases and they solely increase the concentration of enzymes on the substrate surfaces. On the other hand, in practical industrial processes where high substrate concentrations with low amounts of water are employed, the enzymes have been shown to act equally efficiently with and without CBM. Furthermore, available kinetic data show that enzymes without CBMs can desorb more readily from the often lignaceous substrates, that is, they are not stuck on the substrates and are thus available for new actions. In this review, the available data on the natural habitats of different wood-degrading organisms (with emphasis on the amount of water present during wood degradation) and occurrence of cellulose-binding domains in their genome have been assessed in order to identify evolutionary advantages for the development of CBM-less cellulases in nature.
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24
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Shang Y, Su R, Huang R, Yang Y, Qi W, Li Q, He Z. Recycling cellulases by pH-triggered adsorption-desorption during the enzymatic hydrolysis of lignocellulosic biomass. Appl Microbiol Biotechnol 2014; 98:5765-74. [DOI: 10.1007/s00253-014-5761-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2014] [Revised: 04/05/2014] [Accepted: 04/07/2014] [Indexed: 11/30/2022]
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25
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Hama S, Nakano K, Onodera K, Nakamura M, Noda H, Kondo A. Saccharification behavior of cellulose acetate during enzymatic processing for microbial ethanol production. BIORESOURCE TECHNOLOGY 2014; 157:1-5. [PMID: 24514162 DOI: 10.1016/j.biortech.2014.01.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2013] [Revised: 12/29/2013] [Accepted: 01/02/2014] [Indexed: 06/03/2023]
Abstract
This study was conducted to realize the potential application of cellulose acetate to enzymatic processing, followed by microbial ethanol fermentation. To eliminate the effect of steric hindrance of acetyl groups on the action of cellulase, cellulose acetate was subjected to deacetylation in the presence of 1N sodium hydroxide and a mixture of methanol/acetone, yielding 88.8-98.6% at 5-20% substrate loadings during a 48h saccharification at 50°C. Ethanol fermentation using Saccharomyces cerevisiae attained a high yield of 92.3% from the initial glucose concentration of 44.2g/L; however, a low saccharification yield was obtained at 35°C, decreasing efficiency during simultaneous saccharification and fermentation (SSF). Presaccharification at 50°C prior to SSF without increasing the total process time attained the ethanol titers of 19.8g/L (5% substrate), 38.0g/L (10% substrate), 55.9g/L (15% substrate), and 70.9g/L (20% substrate), which show a 12.0-16.2% improvement in ethanol yield.
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Affiliation(s)
- Shinji Hama
- Bio-energy Corporation, Research and Development Laboratory, 2-9-7 Minaminanamatsu, Amagasaki 660-0053, Japan
| | - Kohsuke Nakano
- Bio-energy Corporation, Research and Development Laboratory, 2-9-7 Minaminanamatsu, Amagasaki 660-0053, Japan
| | - Kaoru Onodera
- Bio-energy Corporation, Research and Development Laboratory, 2-9-7 Minaminanamatsu, Amagasaki 660-0053, Japan
| | - Masashi Nakamura
- Bio-energy Corporation, Research and Development Laboratory, 2-9-7 Minaminanamatsu, Amagasaki 660-0053, Japan
| | - Hideo Noda
- Bio-energy Corporation, Research and Development Laboratory, 2-9-7 Minaminanamatsu, Amagasaki 660-0053, Japan
| | - Akihiko Kondo
- Department of Chemical Science and Engineering, Graduate School of Engineering, Kobe University, 1-1 Rokkodai, Nada, Kobe 657-8501, Japan.
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26
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Rodrigues AC, Felby C, Gama M. Cellulase stability, adsorption/desorption profiles and recycling during successive cycles of hydrolysis and fermentation of wheat straw. BIORESOURCE TECHNOLOGY 2014; 156:163-9. [PMID: 24502914 DOI: 10.1016/j.biortech.2014.01.019] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2013] [Revised: 01/03/2014] [Accepted: 01/06/2014] [Indexed: 05/11/2023]
Abstract
The potential of enzymes recycling after hydrolysis and fermentation of wheat straw under a variety of conditions was investigated, monitoring the activity of the enzymes in the solid and liquid fractions, using low molecular weight substrates. A significant amount of active enzymes could be recovered by recycling the liquid phase. In the early stage of the process, enzyme adsorb to the substrate, then gradually returning to the solution as the saccharification proceeds. At 50°C, normally regarded as an acceptable operational temperature for saccharification, the enzymes (Celluclast) significantly undergo thermal deactivation. The hydrolysis yield and enzyme recycling efficiency in consecutive recycling rounds can be increased by using high enzyme loadings and moderate temperatures. Indeed, the amount of enzymes in the liquid phase increased with its thermostability and hydrolytic efficiency. This study contributes towards developing effective enzymes recycling strategies and helping to reduce the enzyme costs on bioethanol production.
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Affiliation(s)
- Ana Cristina Rodrigues
- Centro de Engenharia Biológica, Universidade do Minho, Campus de Gualtar, 4710-057 Braga, Portugal.
| | - Claus Felby
- Department of Geosciences and Natural Resource Management, University of Copenhagen, Rolighedsvej 23, DK-1958 Frederiksberg C, Denmark.
| | - Miguel Gama
- Centro de Engenharia Biológica, Universidade do Minho, Campus de Gualtar, 4710-057 Braga, Portugal.
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27
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Pareek N, Gillgren T, Jönsson LJ. Adsorption of proteins involved in hydrolysis of lignocellulose on lignins and hemicelluloses. BIORESOURCE TECHNOLOGY 2013; 148:70-7. [PMID: 24045193 DOI: 10.1016/j.biortech.2013.08.121] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2013] [Revised: 08/19/2013] [Accepted: 08/20/2013] [Indexed: 05/11/2023]
Abstract
Protein adsorption onto eight lignocellulosic substances (six lignin preparations and two hemicelluloses) was investigated at pH 4.8 and at two different temperatures (4°C and 45°C). The kinetics of the adsorption of cellulase, xylanase, and β-glucosidase were determined by enzyme activity measurements. The maximum adsorption capacities, the affinity constants and the binding strengths varied widely and were typically higher for the lignins than for the carbohydrates. As indicated by BET and gel permeation chromatography, different substances had widely different surface area, pore size, weight average molecular weight, and polydispersity index, but these properties were difficult to relate to protein binding. In most cases, an increase in temperature from 4°C to 45°C and a low content of carboxylic acid groups, as indicated by Fourier-Transform Infra-Red (FTIR) spectroscopy, resulted in increased protein adsorption capacity, which suggests that hydrophobic interactions play an important role.
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Affiliation(s)
- Nidhi Pareek
- Department of Chemistry, Umeå University, SE-901 87 Umeå, Sweden
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28
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Yu Z, Jameel H, Chang HM, Philips R, Park S. Quantification of bound and free enzymes during enzymatic hydrolysis and their reactivities on cellulose and lignocellulose. BIORESOURCE TECHNOLOGY 2013; 147:369-377. [PMID: 23999266 DOI: 10.1016/j.biortech.2013.08.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2013] [Revised: 07/29/2013] [Accepted: 08/02/2013] [Indexed: 05/16/2023]
Abstract
Enzymatic hydrolysis of insoluble biomass is a surface reaction. Part of the enzyme adsorb on the surface of biomass, whereas the others stay in the liquid phase. In this study, three substrates (Avicel cellulose, bleached hardwood pulp, and green-liquor pretreated hardwood pulp) were used to study the reactivity of bound and free enzyme. In a continuous enzymatic hydrolysis, 35-65% initially added enzymes became bound enzymes, which were primarily responsible for enzymatic hydrolysis. The contribution from free enzymes became insignificant after a certain period of reaction time. SDS-PAGE analysis showed that CBH I was significantly decreased in the free enzyme, which might be the reason for the low digestibility of free enzymes due to the loss of synergistic effect. When Tween 80 was added during enzymatic hydrolysis, the digestibility of free enzyme on Avicel was greatly enhanced. However, the benefit of surfactant was not noticeable for lignocellulosic pulps, comparing to Avicel.
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Affiliation(s)
- Zhiying Yu
- Department of Forest Biomaterials, North Carolina State University, Raleigh, NC 27695, USA
| | - Hasan Jameel
- Department of Forest Biomaterials, North Carolina State University, Raleigh, NC 27695, USA
| | - Hou-Min Chang
- Department of Forest Biomaterials, North Carolina State University, Raleigh, NC 27695, USA
| | - Richard Philips
- Department of Forest Biomaterials, North Carolina State University, Raleigh, NC 27695, USA
| | - Sunkyu Park
- Department of Forest Biomaterials, North Carolina State University, Raleigh, NC 27695, USA.
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29
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Ouyang J, Liu B, Zhang M, Zheng Z, Yu H. Enzymatic hydrolysis, adsorption, and recycling during hydrolysis of bagasse sulfite pulp. BIORESOURCE TECHNOLOGY 2013; 146:288-293. [PMID: 23948265 DOI: 10.1016/j.biortech.2013.07.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Revised: 07/05/2013] [Accepted: 07/06/2013] [Indexed: 06/02/2023]
Abstract
The high costs of enzymatic hydrolysis along with the high enzyme dosage are often considered as the major bottlenecks in lignocellulosic bioconversion. This study investigated the hydrolysis efficiency, cellulase adsorption and enzyme recycling during the hydrolysis of bagasse sulfite pulp (BSP). After 48 h of hydrolysis, more than 70% of the cellulose was hydrolyzed, while the protein concentration and cellulase activity in solution remained 31% and 17% of the initial value, respectively. The cellulase adsorption on the fresh BSP was better fitted by a Sips model, suggesting the occurrence of a multilayer adsorption at low cellulase concentration and monolayer adsorption at high concentration on the BSP surfaces. Desorption profile studies showed that the optimum desorption condition was at pH 4.8 and 40 °C. Moreover, considering the limited ability to desorption, directly empolying the bound enzyme with residual substrate is more effective method to recover cellulase during the hydrolysis of BSP.
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Affiliation(s)
- Jia Ouyang
- Jiangsu Key Lab of Biomass-Based Green Fuels and Chemicals, Nanjing 210037, People's Republic of China.
| | - Baotian Liu
- College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, People's Republic of China
| | - Min Zhang
- College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, People's Republic of China
| | - Zhaojuan Zheng
- College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, People's Republic of China
| | - Heng Yu
- College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, People's Republic of China
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30
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Chen G, Song W, Qi B, Lu J, Wan Y. Recycling cellulase from enzymatic hydrolyzate of acid treated wheat straw by electroultrafiltration. BIORESOURCE TECHNOLOGY 2013; 144:186-193. [PMID: 23867538 DOI: 10.1016/j.biortech.2013.06.089] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2013] [Revised: 06/21/2013] [Accepted: 06/22/2013] [Indexed: 06/02/2023]
Abstract
This work explores the feasibility of recycling cellulase by electroultrafiltration (EUF), an ultrafiltration process enhanced by an electric field, to reduce the cost of enzymatic transformation of cellulose. The effect of electric field under different operating conditions (buffer concentration, acid treated wheat straw concentration, current and temperature) on flux during EUF was examined. The results showed that EUF was effective to reduce concentration polarization (CP) and enhance filtration flux in recycling cellulase. The flux improvement by the electric field could be strengthened at low buffer concentration (5 mM) and relatively low temperature (room temperature) and high current (150 mA). The flux for 2% (substrate concentration, w/v) lignocellulosic hydrolyzate increased by a factor of 4.4 at 836 V/m and room temperature, compared to that without electric field. This work shows that under appropriate operating conditions EUF can efficiently recycle cellulase from lignocellulosic hydrolyzate and thus substantially reduce hydrolysis cost.
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Affiliation(s)
- Guoqiang Chen
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
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31
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Nonaka H, Kobayashi A, Funaoka M. Lignin isolated from steam-exploded eucalyptus wood chips by phase separation and its affinity to Trichoderma reesei cellulase. BIORESOURCE TECHNOLOGY 2013; 140:431-4. [PMID: 23711881 DOI: 10.1016/j.biortech.2013.04.109] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2013] [Revised: 04/05/2013] [Accepted: 04/28/2013] [Indexed: 05/24/2023]
Abstract
Steam-exploded eucalyptus wood chips were treated with p-cresol and 72% sulfuric acid at ambient temperature. Steam-exploded lignin was isolated as acetone-soluble and diethyl ether-insoluble compounds from the cresol layer. The lignin extraction yield was only 47%, and the amount of cresol grafted to lignin was much less than that in the case of eucalyptus lignin without steam explosion. Clearly, the steam explosion process depolymerized native lignin, and simultaneously, promoted polymerization via labile benzyl positions. The steam-exploded eucalyptus lignin adsorbed more Trichoderma reesei cellulase; however, its enzymatic activity was less than that of eucalyptus lignin that did not undergo steam explosion. It is evident that pretreatment potentially affects the affinity between lignin and cellulase and the resultant saccharification efficiency.
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Affiliation(s)
- Hiroshi Nonaka
- Graduate School of Bioresources, Mie University, 1577 Kurimamachiya-cho, Tsu, Mie 514-8507, Japan.
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32
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Nonaka H, Kobayashi A, Funaoka M. Behavior of lignin-binding cellulase in the presence of fresh cellulosic substrate. BIORESOURCE TECHNOLOGY 2013; 135:53-57. [PMID: 23186657 DOI: 10.1016/j.biortech.2012.10.065] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2012] [Revised: 10/12/2012] [Accepted: 10/13/2012] [Indexed: 05/18/2023]
Abstract
A model lignin-binding cellulase was prepared from Trichoderma reesei cellulase and lignocresol, which was synthesized from softwood or hardwood lignin. Filter paper was incubated with the lignocresol-cellulase complex, and it was observed that only a limited amount of cellulase migrated to the filter paper. The cellulase adsorption isotherms for the lignocresols and filter paper were fitted to a Langmuir absorption model, and the determined Langmuir constants were as follows: softwood lignocresol>hardwood lignocresol>>filter paper. The calculations demonstrated that lignin-binding cellulase can potentially be recovered by the addition of a sufficient quantity of cellulosic substrate. As a result, the lignocresol-binding cellulase is highly stable and lignocresol can potentially be used for immobilizing cellulase in the active state.
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Affiliation(s)
- Hiroshi Nonaka
- Graduate School of Bioresources, Mie University, Tsu, Mie 514-8507, Japan.
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33
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Marjamaa K, Toth K, Bromann PA, Szakacs G, Kruus K. Novel Penicillium cellulases for total hydrolysis of lignocellulosics. Enzyme Microb Technol 2013; 52:358-69. [DOI: 10.1016/j.enzmictec.2013.03.003] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2012] [Revised: 02/22/2013] [Accepted: 03/03/2013] [Indexed: 10/27/2022]
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34
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Chylenski P, Felby C, Østergaard Haven M, Gama M, Selig MJ. Precipitation of Trichoderma reesei commercial cellulase preparations under standard enzymatic hydrolysis conditions for lignocelluloses. Biotechnol Lett 2012; 34:1475-82. [PMID: 22476551 DOI: 10.1007/s10529-012-0916-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2011] [Accepted: 03/21/2012] [Indexed: 11/24/2022]
Affiliation(s)
- Piotr Chylenski
- Faculty of Science, University of Copenhagen, Rolighedsvej 23, 1958, Frederiksberg C, Denmark.
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35
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Wang Q, Zhu J, Hunt C, Zhan H. Kinetics of adsorption, desorption, and re-adsorption of a commercial endoglucanase in lignocellulosic suspensions. Biotechnol Bioeng 2012; 109:1965-75. [DOI: 10.1002/bit.24483] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2011] [Revised: 02/02/2012] [Accepted: 02/13/2012] [Indexed: 11/06/2022]
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36
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The adsorption and enzyme activity profiles of specific Trichoderma reesei cellulase/xylanase components when hydrolyzing steam pretreated corn stover. Enzyme Microb Technol 2012; 50:195-203. [DOI: 10.1016/j.enzmictec.2011.12.004] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2011] [Revised: 12/07/2011] [Accepted: 12/19/2011] [Indexed: 11/23/2022]
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37
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Sipos B, Szilágyi M, Sebestyén Z, Perazzini R, Dienes D, Jakab E, Crestini C, Réczey K. Mechanism of the positive effect of poly(ethylene glycol) addition in enzymatic hydrolysis of steam pretreated lignocelluloses. C R Biol 2011; 334:812-23. [PMID: 22078738 DOI: 10.1016/j.crvi.2011.06.005] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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38
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Bioconversion of corn stover derived pentose and hexose to ethanol using cascade simultaneous saccharification and fermentation (CSSF). Bioprocess Biosyst Eng 2011; 35:99-104. [DOI: 10.1007/s00449-011-0617-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2011] [Accepted: 07/19/2011] [Indexed: 10/17/2022]
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39
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Lupoi JS, Smith EA. Evaluation of nanoparticle-immobilized cellulase for improved ethanol yield in simultaneous saccharification and fermentation reactions. Biotechnol Bioeng 2011; 108:2835-43. [DOI: 10.1002/bit.23246] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2011] [Revised: 05/31/2011] [Accepted: 06/06/2011] [Indexed: 11/06/2022]
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40
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Qi B, Chen X, Su Y, Wan Y. Enzyme adsorption and recycling during hydrolysis of wheat straw lignocellulose. BIORESOURCE TECHNOLOGY 2011; 102:2881-9. [PMID: 21109424 DOI: 10.1016/j.biortech.2010.10.092] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2010] [Revised: 10/15/2010] [Accepted: 10/20/2010] [Indexed: 05/02/2023]
Abstract
The objective of this research was to investigate cellulase adsorption and recycling during enzymatic hydrolysis of two differently pretreated wheat straws (WS). Dilute acid treated WS showed lower hydrolysis yield of polysaccharides fraction and adsorbed more cellulase with hydrolyzed residue than dilute alkali treated sample. Four methods capable of recovering and recycling the enzyme bound to the residual substrate and the enzyme free in solution were used for three consecutive rounds of hydrolysis to compare their recycling efficiencies. Compared to the absorption recycling method, ultrafiltration recycling method possessed the capacity to retain β-glucosidase, thereby avoiding the supplementation of fresh β-glucosidase in subsequent rounds of hydrolysis. It was found that whatever recycling method was used, better recycling results were obtained for dilute alkali treated substrate than for dilute acid treated substrate. These results suggested that the great difference in the lignin content between acid treated WS and alkali treated WS would significantly affect enzymatic hydrolysis, cellulase adsorption and cellulase recycling efficiencies.
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Affiliation(s)
- Benkun Qi
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, PR China
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Várnai A, Viikari L, Marjamaa K, Siika-aho M. Adsorption of monocomponent enzymes in enzyme mixture analyzed quantitatively during hydrolysis of lignocellulose substrates. BIORESOURCE TECHNOLOGY 2011; 102:1220-7. [PMID: 20736135 DOI: 10.1016/j.biortech.2010.07.120] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2010] [Revised: 07/28/2010] [Accepted: 07/29/2010] [Indexed: 05/03/2023]
Abstract
The adsorption of purified Trichoderma reesei cellulases (TrCel7A, TrCel6A and TrCel5A) and xylanase TrXyn11 and Aspergillus niger β-glucosidase AnCel3A was studied in enzyme mixture during hydrolysis of two pretreated lignocellulosic materials, steam pretreated and catalytically delignified spruce, along with microcrystalline cellulose (Avicel). The enzyme mixture was compiled to resemble the composition of commercial cellulase preparations. The hydrolysis was carried out at 35 °C to mimic the temperature of the simultaneous saccharification and fermentation (SSF). Enzyme adsorption was followed by analyzing the activity and the protein amount of the individual free enzymes in the hydrolysis supernatant. Most enzymes adsorbed quickly at early stages of the hydrolysis and remained bound throughout the hydrolysis, although the conversion reached was fairly high. Only with the catalytically oxidized spruce samples, the bound enzymes started to be released as the hydrolysis degree reached 80%. The results based on enzyme activities and protein assay were in good accordance.
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Affiliation(s)
- Anikó Várnai
- University of Helsinki, Food and Environmental Sciences, P.O. Box 27, 00014 Helsinki, Finland.
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