1
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Danielewicz D. Industrial Hemp as a Potential Nonwood Source of Fibres for European Industrial-Scale Papermaking-A Review. MATERIALS (BASEL, SWITZERLAND) 2023; 16:6548. [PMID: 37834685 PMCID: PMC10573857 DOI: 10.3390/ma16196548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 09/07/2023] [Accepted: 09/13/2023] [Indexed: 10/15/2023]
Abstract
The suitability of industrial hemp (IH) as a source of fibres for European industrial-scale papermaking, including, in particular, European kraft pulp mills (EKMPs) (i.e., plants producing the predominant amount of virgin pulps in Europe), was discussed, considering the causal, cultivation, technological, and application aspects of this issue. The work showed that there are generally premises for using straw from nonwood crops in European papermaking. As for the IH, it was found that IH stalks are the best IH fibrous raw material for EKMPs. There are a few cultivation factors favouring the use of IH stalks in them and a few, though important (e.g., small cultivation areas), factors not conducive to this use. Most technological factors favour the use of IH stalks in EKPMs, apart from the large differences in the length of the IH bast and woody-core fibres. The analysis of application factors indicates lower usefulness of IH stalks than wheat, rye or triticale straws, stalks of Miscanthus × giganteus, Virginia mallow, and kenaf. This is due to the much greater availability of these cereal straws than IH and less variation in the fibre length of cereal straws, Miscanthus × giganteus, Virginia mallow, and kenaf than in IH stalks. The main conclusion from the conducted query is the statement that the presence of IH varieties with fibre lengths more similar to wood would reduce the number of technological and application factors unfavourable to their use in EKPMs and increase the competitiveness of hemp straw vs. wood as a raw material for European large-scale papermaking.
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Affiliation(s)
- Dariusz Danielewicz
- Papermaking Fibrous Pulps Technology Team, Centre of Papermaking and Printing, Lodz University of Technology, Poland, Wolczanska 223 Street, 90-924 Lodz, Poland
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2
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Tong W, Fang H, Song K, Xie X, Wang J, Jin Y, Wu S, Hu J, Chu Q. Modified acid pretreatment to alter physicochemical properties of biomass for full cellulose/hemicellulose utilization. Carbohydr Polym 2023; 299:120182. [PMID: 36876797 DOI: 10.1016/j.carbpol.2022.120182] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2022] [Revised: 09/03/2022] [Accepted: 09/28/2022] [Indexed: 11/05/2022]
Abstract
Acid pretreatment of biomass decomposed hemicelluloses but could not effectively remove lignin, which hindered biomass saccharification and carbohydrates utilization. In this work, 2-naphthol-7-sulfonate (NS) and sodium bisulfite (SUL) were simultaneously added to acid pretreatment, which was found to synergistically increase hydrolysis yield of cellulose from 47.9 % to 90.6 %. Based on in-depth investigations, strong linear correlations were observed between cellulose accessibility and lignin removal, fiber swelling, CrI/cellulose ratio, cellulose crystallite size, respectively, indicating that some physicochemical characteristics of cellulose played significant roles in improving cellulose hydrolysis yield. After enzymatic hydrolysis, 84 % carbohydrates could be liberated and recovered as fermentable sugars for subsequent utilization. Mass balance illustrated that for 100 kg raw biomass, 15.1 kg xylonic acid and 20.5 kg ethanol could be co-produced, indicating the efficient utilization of biomass carbohydrates.
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Affiliation(s)
- Wenyao Tong
- College of Biology and the Environment, Nanjing Forestry University, No. 159 Longpan Road, Nanjing 210037, China
| | - Huaxing Fang
- College of Biology and the Environment, Nanjing Forestry University, No. 159 Longpan Road, Nanjing 210037, China
| | - Kai Song
- College of Biology and the Environment, Nanjing Forestry University, No. 159 Longpan Road, Nanjing 210037, China
| | - Xinyu Xie
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Light Industry and Food Engineering, Nanjing Forestry University, No. 159 Longpan Road, Nanjing 210037, China
| | - Jing Wang
- Guangdong Provincial Key Laboratory of Silviculture, Protection and Utilization, Guangdong Academy of Forestry, Guangzhou 510520, China
| | - Yongcan Jin
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Light Industry and Food Engineering, Nanjing Forestry University, No. 159 Longpan Road, Nanjing 210037, China
| | - Shufang Wu
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Light Industry and Food Engineering, Nanjing Forestry University, No. 159 Longpan Road, Nanjing 210037, China
| | - Jinguang Hu
- Department of Chemical and Petroleum Engineering, University of Calgary, Calgary, AB T2N 1Z4, Canada
| | - Qiulu Chu
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Light Industry and Food Engineering, Nanjing Forestry University, No. 159 Longpan Road, Nanjing 210037, China.
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3
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Kumar A. Dissolving pulp production: Cellulases and xylanases for the enhancement of cellulose accessibility and reactivity. PHYSICAL SCIENCES REVIEWS 2021. [DOI: 10.1515/psr-2019-0047] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Dissolving pulps are high-grade cellulose pulps that have minimum amount of non-cellulosic impurities. Dissolving pulps are the basic source for the manufacturing of several cellulosic products such as viscose, lyocell, cellulose acetates, cellulose nitrates, carboxymethyl-cellulose, etc. Dissolving pulps are mainly manufactured by pre-hydrolysis kraft and acid sulphite pulping. A high reactivity of dissolving pulps is desirable for its eco-friendly utilization for several purposes. Several approaches including mechanical, chemical, ultrasonic, and enzymatic treatments have been employed for the improvement of pulp reactivity. This review mainly focussed on pulp reactivity improvement through enzymatic approaches. Cellulases and xylanase have been proved effective for the improvement of pulp reactivity of dissolving pulp from different sources. The different combinations of cellulase, xylanase, and mechanical refining have been tested and found more effective rather than the single one.
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Affiliation(s)
- Amit Kumar
- Department of Biotechnology , College of Natural and Computational Sciences, Debre Markos University , Debre Markos , 269 Ethiopia
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4
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Wu J, Chandra RP, Takada M, Liu LY, Renneckar S, Kim KH, Kim CS, Saddler JN. Enhancing Enzyme-Mediated Cellulose Hydrolysis by Incorporating Acid Groups Onto the Lignin During Biomass Pretreatment. Front Bioeng Biotechnol 2020; 8:608835. [PMID: 33282856 PMCID: PMC7691530 DOI: 10.3389/fbioe.2020.608835] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Accepted: 10/26/2020] [Indexed: 11/13/2022] Open
Abstract
Lignin is known to limit the enzyme-mediated hydrolysis of biomass by both restricting substrate swelling and binding to the enzymes. Pretreated mechanical pulp (MP) made from Aspen wood chips was incubated with either 16% sodium sulfite or 32% sodium percarbonate to incorporate similar amounts of sulfonic and carboxylic acid groups onto the lignin (60 mmol/kg substrate) present in the pulp without resulting in significant delignification. When Simon's stain was used to assess potential enzyme accessibility to the cellulose, it was apparent that both post-treatments enhanced accessibility and cellulose hydrolysis. To further elucidate how acid group addition might influence potential enzyme binding to lignin, Protease Treated Lignin (PTL) was isolated from the original and modified mechanical pulps and added to a cellulose rich, delignified Kraft pulp. As anticipated, the PTLs from both the oxidized and sulfonated substrates proved less inhibitory and adsorbed less enzymes than did the PTL derived from the original pulp. Subsequent analyses indicated that both the sulfonated and oxidized lignin samples contained less phenolic hydroxyl groups, resulting in enhanced hydrophilicity and a more negative charge which decreased the non-productive binding of the cellulase enzymes to the lignin.
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Affiliation(s)
- Jie Wu
- Forest Product Biotechnology/Bioenergy Group, Department of Wood Science, Faculty of Forestry, University of British Columbia, Vancouver, BC, Canada
| | - Richard P Chandra
- Forest Product Biotechnology/Bioenergy Group, Department of Wood Science, Faculty of Forestry, University of British Columbia, Vancouver, BC, Canada
| | - Masatsugu Takada
- Forest Product Biotechnology/Bioenergy Group, Department of Wood Science, Faculty of Forestry, University of British Columbia, Vancouver, BC, Canada.,International Advanced Energy Science Research and Education Center, Graduate School of Energy Science, Kyoto University, Kyoto, Japan
| | - Li-Yang Liu
- Advanced Renewable Materials Lab, Department of Wood Science, Faculty of Forestry, University of British Columbia, Vancouver, BC, Canada
| | - Scott Renneckar
- Advanced Renewable Materials Lab, Department of Wood Science, Faculty of Forestry, University of British Columbia, Vancouver, BC, Canada
| | - Kwang Ho Kim
- Clean Energy Research Center, Korea Institute of Science and Technology, Seoul, South Korea
| | - Chang Soo Kim
- Clean Energy Research Center, Korea Institute of Science and Technology, Seoul, South Korea
| | - Jack N Saddler
- Forest Product Biotechnology/Bioenergy Group, Department of Wood Science, Faculty of Forestry, University of British Columbia, Vancouver, BC, Canada
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5
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Huang W, Yuan H, Li X. Multi-perspective analyses of rice straw modification by Pleurotus ostreatus and effects on biomethane production. BIORESOURCE TECHNOLOGY 2020; 296:122365. [PMID: 31759858 DOI: 10.1016/j.biortech.2019.122365] [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: 08/17/2019] [Revised: 10/31/2019] [Accepted: 11/01/2019] [Indexed: 06/10/2023]
Abstract
Multi-perspective analyses were carried out to investigate the effect of rice straw modification for 45 days by P. ostreatus on biomethane of production. The results showed that rice straw modified for 25 days achieved the highest biomethane yield of 269 mL·g-1 VS, which was a 26.9% improvement compared with non-modified rice straw. The multi-perspective analyses demonstrated that the improvement resulted from fungal enzymatic reactions, which led to changes in the physicochemical properties of rice straw. The porosity, surface area, acetyl group abundance, degree of polymerization, and lignin degradation selectivity of rice straw modified for 25 days were optimal for enzyme adsorption. Compared with non-modified rice straw, the adsorption of cellulase and xylanase on rice straw modified for 25 days was increased by 18.8% and 58.1%, respectively, which facilitated biomethane production. The study indicated that P. ostreatus is effective for improving biomethane production from rice straw.
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Affiliation(s)
- WenBo Huang
- Department of Environmental Science and Engineering, Beijing University of Chemical Technology, 15 Beisanhuan East Road, Chaoyang District, Beijing 100029, PR China
| | - HaiRong Yuan
- Department of Environmental Science and Engineering, Beijing University of Chemical Technology, 15 Beisanhuan East Road, Chaoyang District, Beijing 100029, PR China
| | - XiuJin Li
- Department of Environmental Science and Engineering, Beijing University of Chemical Technology, 15 Beisanhuan East Road, Chaoyang District, Beijing 100029, PR China.
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6
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Corbett DB, Knoll C, Venditti R, Jameel H, Park S. Fiber fractionation to understand the effect of mechanical refining on fiber structure and resulting enzymatic digestibility of biomass. Biotechnol Bioeng 2019; 117:924-932. [PMID: 31885079 DOI: 10.1002/bit.27258] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 10/25/2019] [Accepted: 12/21/2019] [Indexed: 11/07/2022]
Abstract
Mechanical refining results in fiber deconstruction and modifications that enhance enzyme accessibility to carbohydrates. Further understanding of the morphological changes occurring to biomass during mechanical refining and the impacts of these changes on enzymatic digestibility is necessary to maximize yields and reduce energy consumption. Although the degree of fiber length reduction relative to fibrillation/delamination can be impacted by manipulating refining variables, mechanical refining of any type (PFI, disk, and valley beater) typically results in both phenomena. Separating the two is not straightforward. In this study, fiber fractionation based on particle size performed after mechanical refining of high-lignin pulp was utilized to successfully elucidate the relative impact of fibrillation/delamination and fiber cutting phenomena during mechanical refining. Compositional analysis showed that fines contain significantly more lignin than larger size fractions. Enzymatic hydrolysis results indicated that within fractions of uniform fiber length, fibrillation/delamination due to mechanical refining increased enzymatic conversion by 20-30 percentage points. Changes in fiber length had little effect on digestibility for fibers longer than ~0.5 mm. However, the digestibility of the fines fractions was high for all levels of refining even with the high-lignin content.
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Affiliation(s)
- Derek B Corbett
- Department of Forest Biomaterials, North Carolina State University, Raleigh, North Carolina
| | - Charlie Knoll
- Department of Forest Biomaterials, North Carolina State University, Raleigh, North Carolina
| | - Richard Venditti
- Department of Forest Biomaterials, North Carolina State University, Raleigh, North Carolina
| | - Hasan Jameel
- Department of Forest Biomaterials, North Carolina State University, Raleigh, North Carolina
| | - Sunkyu Park
- Department of Forest Biomaterials, North Carolina State University, Raleigh, North Carolina
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7
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Li M, Guo C, Luo B, Chen C, Wang S, Min D. Comparing impacts of physicochemical properties and hydrolytic inhibitors on enzymatic hydrolysis of sugarcane bagasse. Bioprocess Biosyst Eng 2019; 43:111-122. [PMID: 31538235 DOI: 10.1007/s00449-019-02209-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Revised: 09/01/2019] [Accepted: 09/05/2019] [Indexed: 11/29/2022]
Abstract
An autohydrolysis pretreatment with different conditions was applied to sugarcane bagasse to compare the impacts of the physicochemical properties and hydrolytic inhibitors on its enzymatic hydrolysis. The results indicate that the autohydrolysis conditions significantly affected the physicochemical properties and inhibitors, which further affected the enzymatic hydrolysis. The inhibitor amount, pore size, and crystallinity degree increased with increasing autohydrolysis severity. Furthermore, the enzymatic hydrolysis was enhanced with increasing severity owing to the removal of hemicellulose and lignin. The physicochemical obstruction impeded the enzymatic hydrolysis more than the inhibitors. The multivariate correlated component regression analysis enabled an evaluation of the correlations between the physicochemical properties (and inhibitors) and enzymatic hydrolysis for the first time. According to the results, an autohydrolysis with a severity of 4.01 is an ideal pretreatment for sugarcane bagasse for sugar production.
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Affiliation(s)
- Mingfu Li
- College of Light Industry and Food Engineering, Guangxi University, Nanning, 530004, People's Republic of China.,Guangxi Key Laboratory of Clean Pulp and Papermaking and Pollution Control, Nanning, 530004, People's Republic of China
| | - Chenyan Guo
- College of Light Industry and Food Engineering, Guangxi University, Nanning, 530004, People's Republic of China.,Guangxi Key Laboratory of Clean Pulp and Papermaking and Pollution Control, Nanning, 530004, People's Republic of China
| | - Bin Luo
- College of Light Industry and Food Engineering, Guangxi University, Nanning, 530004, People's Republic of China.,Guangxi Key Laboratory of Clean Pulp and Papermaking and Pollution Control, Nanning, 530004, People's Republic of China
| | - Changzhou Chen
- College of Light Industry and Food Engineering, Guangxi University, Nanning, 530004, People's Republic of China.,Guangxi Key Laboratory of Clean Pulp and Papermaking and Pollution Control, Nanning, 530004, People's Republic of China
| | - Shuangfei Wang
- College of Light Industry and Food Engineering, Guangxi University, Nanning, 530004, People's Republic of China.,Guangxi Key Laboratory of Clean Pulp and Papermaking and Pollution Control, Nanning, 530004, People's Republic of China
| | - Douyong Min
- College of Light Industry and Food Engineering, Guangxi University, Nanning, 530004, People's Republic of China. .,Guangxi Key Laboratory of Clean Pulp and Papermaking and Pollution Control, Nanning, 530004, People's Republic of China.
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8
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Yang S, Yang B, Duan C, Fuller DA, Wang X, Chowdhury SP, Stavik J, Zhang H, Ni Y. Applications of enzymatic technologies to the production of high-quality dissolving pulp: A review. BIORESOURCE TECHNOLOGY 2019; 281:440-448. [PMID: 30876797 DOI: 10.1016/j.biortech.2019.02.132] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 02/01/2019] [Accepted: 02/04/2019] [Indexed: 06/09/2023]
Abstract
Recently, the worldwide production of dissolving pulp has grown rapidly. Enzymatic technologies play an important role in producing high-quality dissolving pulp, due to their green, mild conditions, high specificity and efficiency. In this review, the relevant publications regarding enzyme applications for dissolving pulp are summarized. Cellulase and xylanase are two major enzymes used for this purpose. Cellulase can improve the quality of dissolving pulp, such as improving the reactivity/accessibility, controlling the intrinsic viscosity and adjusting the molecular weight. Xylanase is mainly used to increase the purity of the dissolving pulp and improve the pulp brightness. Furthermore, in order to increase the enzymatic treatment efficiency, the enzymatic technology can be combined with other techniques, including mechanical refining, fiber fractionations, alkali treatment and use of additives. The advantages, disadvantages and practical implications are analyzed. Also, the potential of other enzymes (such as laccase, mannanase) are discussed.
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Affiliation(s)
- Shuo Yang
- Tianjin Key Laboratory of Pulp and Paper, College of Paper Making Science and Technology, Tianjin University of Science and Technology, Tianjin 300457, China; Limerick Pulp & Paper Centre & Department of Chemical Engineering, University of New Brunswick, Fredericton, NB E3B 5A3, Canada
| | - Bo Yang
- Limerick Pulp & Paper Centre & Department of Chemical Engineering, University of New Brunswick, Fredericton, NB E3B 5A3, Canada
| | - Chao Duan
- College of Bioresources Chemical and Materials Engineering, Shaanxi Provincial Key Laboratory of Papermaking Technology and Specialty Paper Development, Shaanxi University of Science and Technology, Xi'an 710021, China
| | - Darcy Alexandra Fuller
- Limerick Pulp & Paper Centre & Department of Chemical Engineering, University of New Brunswick, Fredericton, NB E3B 5A3, Canada
| | - Xinqi Wang
- Limerick Pulp & Paper Centre & Department of Chemical Engineering, University of New Brunswick, Fredericton, NB E3B 5A3, Canada; College of Bioresources Chemical and Materials Engineering, Shaanxi Provincial Key Laboratory of Papermaking Technology and Specialty Paper Development, Shaanxi University of Science and Technology, Xi'an 710021, China
| | - Susmita Paul Chowdhury
- Limerick Pulp & Paper Centre & Department of Chemical Engineering, University of New Brunswick, Fredericton, NB E3B 5A3, Canada
| | - Jaroslav Stavik
- Schweighofer Fiber GmbH, Salzachtalstraße 88, Postfach 62, 5400 Hallein, Austria
| | - Hongjie Zhang
- Tianjin Key Laboratory of Pulp and Paper, College of Paper Making Science and Technology, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Yonghao Ni
- Tianjin Key Laboratory of Pulp and Paper, College of Paper Making Science and Technology, Tianjin University of Science and Technology, Tianjin 300457, China; Limerick Pulp & Paper Centre & Department of Chemical Engineering, University of New Brunswick, Fredericton, NB E3B 5A3, Canada.
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9
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Digaitis R, Thybring EE, Thygesen LG. Investigating the role of mechanics in lignocellulosic biomass degradation during hydrolysis. Biotechnol Prog 2018; 35:e2754. [PMID: 30468315 DOI: 10.1002/btpr.2754] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Revised: 10/13/2018] [Accepted: 11/20/2018] [Indexed: 11/12/2022]
Abstract
Enzymes and mechanics play major roles in lignocellulosic biomass deconstruction in biorefineries by catalyzing chemical cleavage or inducing physical breakdown of biomass, respectively. At industrially relevant substrate concentrations mechanical agitation is also a driving force for mass transfer as well as agglomeration of elongated biomass particles. Contrary to the physically induced particle attrition, which typically facilitates feedstock handling, particle agglomeration tends to hinder mass transfer and in the worst case induces processing difficulties like pipe blockage. Understanding the complex interplay between mechanical agitation and enzymatic degradation during hydrolysis is therefore critical and was the aim of this study. Particle size analyses revealed that neither mechanical agitation alone nor enzymatic treatment without mechanical agitation had any noteworthy effect on flax fiber attrition. Similarly, successive treatment, where mechanical agitation was either preceded or proceeded by enzymatic hydrolysis, did not induce any substantial segmentation of flax fibers. Simultaneous enzymatic and mechanical treatment on the other hand was found to promote fast fiber shortening. Higher hydrolysis yields, however, were obtained from nonagitated samples after prolonged enzymatic treatment, indicating that mechanical agitation in the long run reduces activity of the cellulolytic enzymes. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 35: e2754, 2019.
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Affiliation(s)
- Ramūnas Digaitis
- Dept. of Geosciences and Natural Resource Management, Faculty of Science, University of Copenhagen, Rolighedsvej 23, Frederiksberg C, Denmark
| | - Emil Engelund Thybring
- Dept. of Geosciences and Natural Resource Management, Faculty of Science, University of Copenhagen, Rolighedsvej 23, Frederiksberg C, Denmark
| | - Lisbeth Garbrecht Thygesen
- Dept. of Geosciences and Natural Resource Management, Faculty of Science, University of Copenhagen, Rolighedsvej 23, Frederiksberg C, Denmark
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10
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Lambert E, Aguié-Béghin V, Dessaint D, Foulon L, Chabbert B, Paës G, Molinari M. Real Time and Quantitative Imaging of Lignocellulosic Films Hydrolysis by Atomic Force Microscopy Reveals Lignin Recalcitrance at Nanoscale. Biomacromolecules 2018; 20:515-527. [DOI: 10.1021/acs.biomac.8b01539] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Eléonore Lambert
- LRN EA 4682, Université de Reims Champagne-Ardenne, 51685 Reims, France
| | | | - Delphine Dessaint
- FARE Laboratory, INRA, Université de Reims Champagne-Ardenne, 51100, Reims, France
| | - Laurence Foulon
- FARE Laboratory, INRA, Université de Reims Champagne-Ardenne, 51100, Reims, France
| | - Brigitte Chabbert
- FARE Laboratory, INRA, Université de Reims Champagne-Ardenne, 51100, Reims, France
| | - Gabriel Paës
- FARE Laboratory, INRA, Université de Reims Champagne-Ardenne, 51100, Reims, France
| | - Michaël Molinari
- LRN EA 4682, Université de Reims Champagne-Ardenne, 51685 Reims, France
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11
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Bağder Elmacı S, Özçelik F. Ionic liquid pretreatment of yellow pine followed by enzymatic hydrolysis and fermentation. Biotechnol Prog 2018; 34:1242-1250. [DOI: 10.1002/btpr.2661] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Revised: 04/27/2018] [Indexed: 01/24/2023]
Affiliation(s)
- Simel Bağder Elmacı
- Faculty of Engineering, Dept. of Food EngineeringAnkara University Ankara Turkey
| | - Filiz Özçelik
- Faculty of Engineering, Dept. of Food EngineeringAnkara University Ankara Turkey
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12
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Yang S, Wen Y, Zhang H, Li J, Ni Y. Enhancing the Fock reactivity of dissolving pulp by the combined prerefining and poly dimethyl diallyl ammonium chloride-assisted cellulase treatment. BIORESOURCE TECHNOLOGY 2018; 260:135-140. [PMID: 29625285 DOI: 10.1016/j.biortech.2018.03.119] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 03/24/2018] [Accepted: 03/26/2018] [Indexed: 05/25/2023]
Abstract
Dissolving pulp is an important source of cellulose raw material, and its key quality parameter is the Fock reactivity for viscose rayon application. Cellulase treatment is an effective method for improving the Fock reactivity of kraft-based dissolving pulp. In this study, a novel process concept of improving the cellulase treatment for this purpose was developed, and it consists of mechanical pre-refining and PDADMAC-assisted cellulase treatment. The hypothesis is based on: 1) opening up the fiber structures to improve the cellulase accessibility by pulp prerefining, 2) the addition of cationic poly DADMAC to the subsequent cellulase stage enhances the cellulase adsorption onto anionic fibers due to favorable electrostatic interactions. The results showed that the Fock reactivity of the resultant pulp from the combined treatment is much higher than that of the control, yet, achieved at a much lower cellulase dosage.
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Affiliation(s)
- Shuo Yang
- Tianjin Key Laboratory of Pulp and Paper, Tianjin University of Science & Technology, Tianjin 300457, China; Limerick Pulp & Paper Centre & Department of Chemical Engineering, University of New Brunswick, Fredericton, NB, E3B 5A3, Canada
| | - Yangbing Wen
- Tianjin Key Laboratory of Pulp and Paper, Tianjin University of Science & Technology, Tianjin 300457, China
| | - Hongjie Zhang
- Tianjin Key Laboratory of Pulp and Paper, Tianjin University of Science & Technology, Tianjin 300457, China
| | - Jianguo Li
- College of Material Engineering, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Yonghao Ni
- Tianjin Key Laboratory of Pulp and Paper, Tianjin University of Science & Technology, Tianjin 300457, China; Limerick Pulp & Paper Centre & Department of Chemical Engineering, University of New Brunswick, Fredericton, NB, E3B 5A3, Canada.
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13
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Duan C, Wang X, Zhang Y, Xu Y, Ni Y. Fractionation and cellulase treatment for enhancing the properties of kraft-based dissolving pulp. BIORESOURCE TECHNOLOGY 2017; 224:439-444. [PMID: 27815045 DOI: 10.1016/j.biortech.2016.10.077] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Revised: 10/22/2016] [Accepted: 10/25/2016] [Indexed: 06/06/2023]
Abstract
The aim of this study was to investigate a combined process involving pulp fractionation and cellulase treatment of each fraction for improving the molecular weight distribution (MWD) and reactivity of a kraft-based dissolving pulp. Three pulp fractions, namely long-fiber, mid-fiber and short-fiber fractions (LF, MF and SF, respectively), were used as the substrates. The results showed that the SF had the highest accessibility, lowest viscosity, and highest cellulase adsorption capacity, while the opposite was true for the LF. At a given viscosity, the combined process led to a lower polydispersity index (3.71 vs 4.98) and a higher Fock reactivity (85.6% vs 76.3%), in comparison to the conventional single-stage cellulase treatment.
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Affiliation(s)
- Chao Duan
- College of Bioresources Chemical and Materials Engineering, Shaanxi University of Science and Technology, Xi'an 710021, China; Limerick Pulp and Paper Centre, University of New Brunswick, Fredericton, New Brunswick E3B 5A3, Canada.
| | - Xinqi Wang
- College of Bioresources Chemical and Materials Engineering, Shaanxi University of Science and Technology, Xi'an 710021, China
| | - YanLing Zhang
- College of Bioresources Chemical and Materials Engineering, Shaanxi University of Science and Technology, Xi'an 710021, China
| | - Yongjian Xu
- College of Bioresources Chemical and Materials Engineering, Shaanxi University of Science and Technology, Xi'an 710021, China
| | - Yonghao Ni
- College of Bioresources Chemical and Materials Engineering, Shaanxi University of Science and Technology, Xi'an 710021, China; Limerick Pulp and Paper Centre, University of New Brunswick, Fredericton, New Brunswick E3B 5A3, Canada
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14
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Arslan B, Colpan M, Ju X, Zhang X, Kostyukova A, Abu-Lail NI. The Effects of Noncellulosic Compounds on the Nanoscale Interaction Forces Measured between Carbohydrate-Binding Module and Lignocellulosic Biomass. Biomacromolecules 2016; 17:1705-15. [PMID: 27065303 DOI: 10.1021/acs.biomac.6b00129] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The lack of fundamental understanding of the types of forces that govern how cellulose-degrading enzymes interact with cellulosic and noncellulosic components of lignocellulosic surfaces limits the design of new strategies for efficient conversion of biomass to bioethanol. In a step to improve our fundamental understanding of such interactions, nanoscale forces acting between a model cellulase-a carbohydrate-binding module (CBM) of cellobiohydrolase I (CBH I)-and a set of lignocellulosic substrates with controlled composition were measured using atomic force microscopy (AFM). The three model substrates investigated were kraft (KP), sulfite (SP), and organosolv (OPP) pulped substrates. These substrates varied in their surface lignin coverage, lignin type, and xylan and acetone extractives' content. Our results indicated that the overall adhesion forces of biomass to CBM increased linearly with surface lignin coverage with kraft lignin showing the highest forces among lignin types investigated. When the overall adhesion forces were decoupled into specific and nonspecific component forces via the Poisson statistical model, hydrophobic and Lifshitz-van der Waals (LW) forces dominated the binding forces of CBM to kraft lignin, whereas permanent dipole-dipole interactions and electrostatic forces facilitated the interactions of lignosulfonates to CBM. Xylan and acetone extractives' content increased the attractive forces between CBM and lignin-free substrates, most likely through hydrogen bonding forces. When the substrates treated differently were compared, it was found that both the differences in specific and nonspecific forces between lignin-containing and lignin-free substrates were the least for OPP. Therefore, cellulase enzymes represented by CBM would weakly bind to organosolv lignin. This will facilitate an easy enzyme recovery compared to other substrates treated with kraft or sulfite pulping. Our results also suggest that altering the surface hydrophobicity and the surface energy of lignin that facilitates the LW forces should be a priori to avoid nonproductive binding of cellulase to kraft lignin.
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Affiliation(s)
- Baran Arslan
- Gene and Linda Voiland School of Chemical Engineering and Bioengineering, Washington State University , Pullman, Washington 99164-6515, United States
| | - Mert Colpan
- Gene and Linda Voiland School of Chemical Engineering and Bioengineering, Washington State University , Pullman, Washington 99164-6515, United States
| | - Xiaohui Ju
- Gene and Linda Voiland School of Chemical Engineering and Bioengineering, Bioproducts' Science and Engineering Laboratory, Washington State University , Richland, Washington 99354-1670, United States
| | - Xiao Zhang
- Gene and Linda Voiland School of Chemical Engineering and Bioengineering, Bioproducts' Science and Engineering Laboratory, Washington State University , Richland, Washington 99354-1670, United States
| | - Alla Kostyukova
- Gene and Linda Voiland School of Chemical Engineering and Bioengineering, Washington State University , Pullman, Washington 99164-6515, United States
| | - Nehal I Abu-Lail
- Gene and Linda Voiland School of Chemical Engineering and Bioengineering, Washington State University , Pullman, Washington 99164-6515, United States
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15
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Karimi K, Taherzadeh MJ. A critical review on analysis in pretreatment of lignocelluloses: Degree of polymerization, adsorption/desorption, and accessibility. BIORESOURCE TECHNOLOGY 2016; 203:348-56. [PMID: 26778166 DOI: 10.1016/j.biortech.2015.12.035] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Revised: 12/12/2015] [Accepted: 12/13/2015] [Indexed: 05/18/2023]
Abstract
The pretreatment of lignocelluloses results in changes in the different properties of these materials. In a recent review (Karimi and Taherzadeh, 2016), the details of compositional, imaging, and crystallinity analyses of lignocelluloses were reviewed and critically discussed. Changes in the cellulose degree of polymerization, accessibility, and enzyme adsorption/desorption by pretreatments are also among the effective parameters. This paper deals with the measurement techniques, modifications, and relation to bioconversions, as well as the challenges of these three properties. These analyses are very helpful to investigate the pretreatment processes; however, the pretreatments are very complicated and challenging processes. It is not easily possible to study the effects of only one of these parameters and even to find which one is the dominant one. Moreover, it is not possible to accurately predict the changes in the bioconversion yield using these methods.
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Affiliation(s)
- Keikhosro Karimi
- Department of Chemical Engineering, Isfahan University of Technology, Isfahan 84156-83111, Iran; Industrial Biotechnology Group, Institute of Biotechnology and Bioengineering, Isfahan University of Technology, Isfahan 84156-83111, Iran
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16
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Jiang J, Wang J, Zhang X, Wolcott M. Evaluation of physical structural features on influencing enzymatic hydrolysis efficiency of micronized wood. RSC Adv 2016. [DOI: 10.1039/c6ra22371k] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Enzymatic hydrolysis of lignocellulosic biomass is highly dependent on the changes in structural features after pretreatment.
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Affiliation(s)
- Jinxue Jiang
- Composite Materials and Engineering Center
- Washington State University
- Pullman
- USA
| | - Jinwu Wang
- Forest Products Laboratory
- United States Department of Agriculture Forest Service
- Orono
- USA
| | - Xiao Zhang
- Voiland School of Chemical Engineering and Bioengineering
- Washington State University
- Richland
- USA
| | - Michael Wolcott
- Composite Materials and Engineering Center
- Washington State University
- Pullman
- USA
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17
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Park J, Jones B, Koo B, Chen X, Tucker M, Yu JH, Pschorn T, Venditti R, Park S. Use of mechanical refining to improve the production of low-cost sugars from lignocellulosic biomass. BIORESOURCE TECHNOLOGY 2016; 199:59-67. [PMID: 26338276 DOI: 10.1016/j.biortech.2015.08.059] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Revised: 08/11/2015] [Accepted: 08/12/2015] [Indexed: 05/25/2023]
Abstract
Mechanical refining is widely used in the pulp and paper industry to enhance the end-use properties of products by creating external fibrillation and internal delamination. This technology can be directly applied to biochemical conversion processes. By implementing mechanical refining technology, biomass recalcitrance to enzyme hydrolysis can be overcome and carbohydrate conversion can be enhanced with commercially attractive levels of enzymes. In addition, chemical and thermal pretreatment severity can be reduced to achieve the same level of carbohydrate conversion, which reduces pretreatment cost and results in lower concentrations of inhibitors. Refining is versatile and a commercially proven technology that can be operated at process flows of ∼ 1500 dry tons per day of biomass. This paper reviews the utilization of mechanical refining in the pulp and paper industry and summarizes the recent development in applications for biochemical conversion, which potentially make an overall biorefinery process more economically viable.
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Affiliation(s)
- Junyeong Park
- Department of Forest Biomaterials, North Carolina State University, Raleigh, NC 27695, USA
| | - Brandon Jones
- Department of Forest Biomaterials, North Carolina State University, Raleigh, NC 27695, USA
| | | | - Xiaowen Chen
- National Bioenergy Center, National Renewable Energy Laboratory, Golden, CO 80127, USA
| | - Melvin Tucker
- National Bioenergy Center, National Renewable Energy Laboratory, Golden, CO 80127, USA
| | - Ju-Hyun Yu
- Korea Research Institute of Chemical Technology, Daejeon, Republic of Korea
| | | | - Richard Venditti
- 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; Department of Forest Sciences, Seoul National University, Seoul, Republic of Korea.
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18
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Preparation and Application of Cationic Modified Cellulose Fibrils as a Papermaking Additive. INT J POLYM SCI 2016. [DOI: 10.1155/2016/6978434] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
This paper deals with cationic modified cellulose fibrils obtained by reacting the cellulose fibrils with 2,3-epoxypropyltrimethylammonium chloride (EPTMAC). The physical and chemical properties of unmodified cellulose fibrils (UMCF) and cationic modified cellulose fibrils (CMCF) were characterized by SEM, FTIR, degree of substitution, colloid titration, zeta potential, and thermogravimetric analysis. The experimental results showed that, after cationization, surface charge density and zeta potential reversed, thermal stability decreased, and new functional groups appeared, while the surface morphology did not show much difference from the UMCF. With the addition of three kinds of additives (UMCF, CMCF, and cationic starch (CS)) to BCTMP, the addition of UMCF and CMCF had little effect on zeta potential, while the addition of CS changed zeta potential obviously. With the increasing of additive amount, the bulk of paper sheets added CMCF did not change obviously, while the bulk of paper sheets added UMCF and CS decreased rapidly. With regard to physical strength, all the three kinds of additives could improve the tensile index and tear index; the tensile index of paper sheets added CS was higher than that of added UMCF and CMCF, while the tear index of paper sheets added CMCF was the highest among the three additives.
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19
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Athmanathan A, Trupia S. Examining the role of particle size on ammonia-based bioprocessing of maize stover. Biotechnol Prog 2015; 32:134-40. [PMID: 26587736 DOI: 10.1002/btpr.2203] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Revised: 11/17/2015] [Indexed: 11/10/2022]
Abstract
The role of particle size in carbohydrate fractionation upon pretreatment and glucan yields upon enzymatic hydrolysis was investigated at two different temperatures, to examine the possibility of pretreating under milder conditions smaller particles, in order to satisfy pilot-scale operational constraints. Maize stover was knife-milled through 1-mm and 0.5-mm screens and pretreated by soaking in aqueous ammonia pretreatment at 60 or 110°C for 6 h. Pretreated solids were analyzed for composition and a material balance calculated for glucan, xylan, and lignin. At 60°C, milling resulted in greater delignification compared to unmilled biomass. Delignification was more uniform at 110°C. Pretreated solids were washed and cellulase hydrolysis carried out at 10% w/w solids loading, with low and high enzyme loadings. Liquid samples were drawn and concentration data developed through HPLC to calculate 48-h glucan and xylan hydrolytic yields. The differences in hydrolytic yield between milled and unmilled treatments were found to vary with pretreatment temperature and enzyme loading. The results show that while particle size impacts carbohydrate recovery and hydrolytic yield, it is less important in bioprocessing than pretreatment temperature and enzyme loading, possibly owing to the particles' morphology rather than the size.
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Affiliation(s)
- Arun Athmanathan
- National Corn-to-Ethanol Research Center (NCERC), The Graduate Schoool, Southern Illinois University, Edwardsville, IL, 62026
| | - Sabrina Trupia
- National Corn-to-Ethanol Research Center (NCERC), The Graduate Schoool, Southern Illinois University, Edwardsville, IL, 62026
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20
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Analysis of a Modern Hybrid and an Ancient Sugarcane Implicates a Complex Interplay of Factors in Affecting Recalcitrance to Cellulosic Ethanol Production. PLoS One 2015; 10:e0134964. [PMID: 26252208 PMCID: PMC4529190 DOI: 10.1371/journal.pone.0134964] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2015] [Accepted: 07/15/2015] [Indexed: 11/19/2022] Open
Abstract
Abundant evidence exists to support a role for lignin as an important element in biomass recalcitrance. However, several independent studies have also shown that factors apart from lignin are also relevant and overall, the relative importance of different recalcitrance traits remains in dispute. In this study we used two genetically distant sugarcane genotypes, and performed a correlational study with the variation in anatomical parameters, cell wall composition, and recalcitrance factors between these genotypes. In addition we also tracked alterations in these characteristics in internodes at different stages of development. Significant differences in the development of the culm between the genotypes were associated with clear differential distributions of lignin content and composition that were not correlated with saccharification and fermentation yield. Given the strong influence of the environment on lignin content and composition, we hypothesized that sampling within a single plant could allow us to more easily interpret recalcitrance and changes in lignin biosynthesis than analysing variations between different genotypes with extensive changes in plant morphology and culm anatomy. The syringyl/guaiacyl (S/G) ratio was higher in the oldest internode of the modern genotype, but S/G ratio was not correlated with enzymatic hydrolysis yield nor fermentation efficiency. Curiously we observed a strong positive correlation between ferulate ester level and cellulose conversion efficiency. Together, these data support the hypothesis that biomass enzymatic hydrolysis recalcitrance is governed by a quantitative heritage rather than a single trait.
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21
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Liu Z, Inokuma K, Ho SH, Haan RD, Hasunuma T, van Zyl WH, Kondo A. Combined cell-surface display- and secretion-based strategies for production of cellulosic ethanol with Saccharomyces cerevisiae. BIOTECHNOLOGY FOR BIOFUELS 2015; 8:162. [PMID: 26413161 PMCID: PMC4584016 DOI: 10.1186/s13068-015-0344-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Accepted: 09/18/2015] [Indexed: 05/12/2023]
Abstract
BACKGROUND Engineering Saccharomyces cerevisiae to produce heterologous cellulases is considered as a promising strategy for production of bioethanol from lignocellulose. The production of cellulase is usually pursued by one of the two strategies: displaying enzyme on the cell surface or secreting enzyme into the medium. However, to our knowledge, the combination of the two strategies in a yeast strain has not been employed. RESULTS In this study, heterologous endoglucanase (EG) and cellobiohydrolase I (CBHI) were produced in a β-glucosidase displaying S. cerevisiae strain using cell-surface display, secretion, or a combined strategy. Strains EG-D-CBHI-D and EG-S-CBHI-S (with both enzymes displayed on the cell surface or with both enzymes secreted to the surrounding medium) showed higher ethanol production (2.9 and 2.6 g/L from 10 g/L phosphoric acid swollen cellulose, respectively), than strains EG-D-CBHI-S and EG-S-CBHI-D (with EG displayed on cell surface and CBHI secreted, or vice versa). After 3-cycle repeated-batch fermentation, the cellulose degradation ability of strain EG-D-CBHI-D remained 60 % of the 1st batch, at a level that was 1.7-fold higher than that of strain EG-S-CBHI-S. CONCLUSIONS This work demonstrated that placing EG and CBHI in the same space (on the cell surface or in the medium) was favorable for amorphous cellulose-based ethanol fermentation. In addition, the cellulolytic yeast strain that produced enzymes by the cell-surface display strategy performed better in cell-recycle batch fermentation compared to strains producing enzymes via the secretion strategy.
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Affiliation(s)
- Zhuo Liu
- />Department of Chemical Science and Engineering, Graduate School of Engineering, Kobe University, 1-1 Rokkodai, Nada-ku, Kobe, 657-8501 Japan
| | - Kentaro Inokuma
- />Organization of Advanced Science and Technology, Kobe University, 1-1 Rokkodai, Nada-ku, Kobe, 657-8501 Japan
| | - Shih-Hsin Ho
- />Organization of Advanced Science and Technology, Kobe University, 1-1 Rokkodai, Nada-ku, Kobe, 657-8501 Japan
- />State Key Laboratory of Urban Water Resource and Environment, School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin, 150090 People’s Republic of China
| | - Riaan den Haan
- />Department of Biotechnology, University of the Western Cape, Bellville, 7530 South Africa
| | - Tomohisa Hasunuma
- />Organization of Advanced Science and Technology, Kobe University, 1-1 Rokkodai, Nada-ku, Kobe, 657-8501 Japan
| | - Willem H. van Zyl
- />Department of Microbiology, University of Stellenbosch, Stellenbosch, 7600 South Africa
| | - Akihiko Kondo
- />Department of Chemical Science and Engineering, Graduate School of Engineering, Kobe University, 1-1 Rokkodai, Nada-ku, Kobe, 657-8501 Japan
- />Biomass Engineering Program, RIKEN, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045 Japan
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22
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Ju X, Bowden M, Engelhard M, Zhang X. Investigating commercial cellulase performances toward specific biomass recalcitrance factors using reference substrates. Appl Microbiol Biotechnol 2013; 98:4409-20. [PMID: 24337347 DOI: 10.1007/s00253-013-5450-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2013] [Revised: 11/26/2013] [Accepted: 11/28/2013] [Indexed: 11/29/2022]
Abstract
Three commercial cellulase preparations, Novozymes Cellic(®) Ctec2, Dupont Accellerase(®) 1500, and DSM Cytolase CL, were evaluated for their hydrolytic activity using a set of reference biomass substrates with controlled substrate characteristics. It was found that lignin remains a significant recalcitrance factor to all the preparations, although different enzyme preparations respond to the inhibitory effect of lignin differently. Also, different types of biomass lignin can inhibit cellulase enzymes in different manners. Enhancing enzyme activity toward biomass fiber swelling is an area significantly contributing to potential improvement in cellulase performance. While the degree of polymerization of cellulose in the reference substrates did not present a major recalcitrance factor to Novozymes Cellic(®) Ctec2, cellulose crystallite has been shown to have a significant lower reactivity toward all enzyme mixtures. The presence of polysaccharide monooxygenases (PMOs) in Novozymes Ctec2 appears to enhance enzyme activity toward decrystallization of cellulose. This study demonstrated that reference substrates with controlled chemical and physical characteristics of structural features can be applied as an effective and practical strategy to identify cellulosic enzyme activities toward specific biomass recalcitrance factor(s) and provide specific targets for enzyme improvement.
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Affiliation(s)
- Xiaohui Ju
- Voiland School of Chemical Engineering and Bioengineering, Bioproducts, Science and Engineering Laboratory, Washington State University, Richland, WA, 99354, USA
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