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Ramtanon I, Berlioz-Barbier A, Remy S, Renault JH, Masle AL. A combined liquid chromatography - trapped ion mobility - tandem high-resolution mass spectrometry and multivariate analysis approach for the determination of enzymatic reactivity descriptors in biomass hydrolysates. J Chromatogr A 2023; 1706:464277. [PMID: 37573756 DOI: 10.1016/j.chroma.2023.464277] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Revised: 07/17/2023] [Accepted: 08/02/2023] [Indexed: 08/15/2023]
Abstract
Intermediate products such as oxygenated compounds may interfere with bioconversion kinetics of lignocellulosic biomass into bioethanol. This work presents a multidimensional approach, based on liquid chromatography (LC), trapped ion mobility spectrometry (TIMS), tandem high-resolution mass spectrometry (HRMS/MS), and multivariate analysis, for the identification of enzymatic reactivity descriptors in 22 industrial biomass samples, called hydrolysates. The first part of the study is dedicated to the improvement of the chemical diversity assessment of the hydrolysates through an original three-dimensional Van Krevelen diagram displaying the double bond equivalent (DBE) as third dimension. In a second part, the evaluation of data by multivariate data analysis allowed the discrimination of sample according to the biomass type and the level of enzymatic reactivity. In the last part, a potential descriptor of low enzymatic reactivity was selected and used in a case study. An in-depth structural analysis was performed on the feature annotated as carbohydrate derivative. Considering the intricate fragmentation spectrum exhibited by the selected feature, trapped ion mobility was employed to enhance separation prior to the HRMS/MS experiments. This final step improved data interpretation and increased the identification confidence level leading to the characterization of xylotriose, 3,5-dimethoxy-4-hydroxybenzaldehyde and 4-hydroxy-3-methoxy-cinnamaldehyde. This is the first study to present an untargeted multidimensional approach for the identification of enzymatic hydrolysis inhibitors in industrial hydrolysate samples.
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Affiliation(s)
- Ian Ramtanon
- IFP Energies nouvelles, rond-point de l'échangeur de Solaize, BP 3, 69360 Solaize, France
| | | | - Simon Remy
- Université de Reims Champagne-Ardenne, CNRS, ICMR 7312, 51097, Reims, France
| | - Jean-Hugues Renault
- Université de Reims Champagne-Ardenne, CNRS, ICMR 7312, 51097, Reims, France
| | - Agnès Le Masle
- IFP Energies nouvelles, rond-point de l'échangeur de Solaize, BP 3, 69360 Solaize, France.
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2
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Efficient Corncob Biorefinery for Ethanol Initiated by a Novel Pretreatment of Densifying Lignocellulosic Biomass with Sulfuric Acid. FERMENTATION-BASEL 2022. [DOI: 10.3390/fermentation8110661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Corncob is a potential feedstock for biorefineries to produce cellulosic ethanol and other chemicals. Densifying lignocellulosic biomass with chemicals followed by autoclave (DLCA) has been confirmed an efficient and economical pretreatment method, and it was applied in the present work for conversion of corncob to bioethanol. The dosage of sulfuric acid, solid loading of biomass, and autoclave time for pretreatment were investigated. Enzymatic hydrolysis at 25–35% solids loadings resulted in 91–97% sugar conversions. Fermentation of the resulted hydrolysates went well with the highest ethanol titer reaching 75.71 g/L at 35% solid loading. Simultaneous saccharification and co-fermentation was applied to further improve xylose consumption at high solids loadings and the ethanol titer was enhanced to 82.0 g/L at 35% solid loading with an ethanol yield of 21.67 kg/100 kg corncob. This study demonstrated DLCA provided a highly digestible and highly fermentable corncob for biorefinery.
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Lucaroni AC, Dresch AP, Fogolari O, Giehl A, Treichel H, Bender JP, Mibielli GM, Alves SL. Effects of Temperature and pH on Salt-Stressed Yeast Cultures in Non-Detoxified Coconut Hydrolysate. Ind Biotechnol (New Rochelle N Y) 2022. [DOI: 10.1089/ind.2021.0029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Ana C. Lucaroni
- Laboratory of Biochemistry and Genetics, Federal University of Fronteira Sul, Chapecó, SC, Brazil
| | - Aline P. Dresch
- Laboratory of Solid Waste, Federal University of Fronteira Sul, Chapecó, SC, Brazil
| | - Odinei Fogolari
- Laboratory of Biochemistry and Genetics, Federal University of Fronteira Sul, Chapecó, SC, Brazil
- Laboratory of Solid Waste, Federal University of Fronteira Sul, Chapecó, SC, Brazil
| | - Anderson Giehl
- Laboratory of Biochemistry and Genetics, Federal University of Fronteira Sul, Chapecó, SC, Brazil
| | - Helen Treichel
- Laboratory of Microbiology and Bioprocesses, Federal University of Fronteira Sul, Erechim, RS, Brazil
| | - João P. Bender
- Laboratory of Solid Waste, Federal University of Fronteira Sul, Chapecó, SC, Brazil
| | | | - Sérgio L. Alves
- Laboratory of Biochemistry and Genetics, Federal University of Fronteira Sul, Chapecó, SC, Brazil
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Du J, Liang J, Zhang X, Wang J, Li W, Song P, Feng X. Identifying the negative cooperation between major inhibitors of cellulase activity and minimizing their inhibitory potential during hydrolysis of acid-pretreated corn stover. BIORESOURCE TECHNOLOGY 2022; 343:126113. [PMID: 34648965 DOI: 10.1016/j.biortech.2021.126113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Revised: 10/06/2021] [Accepted: 10/07/2021] [Indexed: 06/13/2023]
Abstract
Soluble compounds produced during the enzymatic hydrolysis of lignocelluloses hampers cellulose conversion. Cellobiose and vanillin most severely inhibited the effect of cellobiohydrolase I. A concentration-dependent negative cooperative effect was found between cellobiose and vanillin. The combined inhibitory effect was about 83.5% of the cellobiose and 88.1% of the vanillin when their concentration was 20 mg/ml. However, the negative synergy could be eliminated by excessive enzyme loading. Differences in their binding sites on the catalytic domain of cellobiohydrolase I lead to negative synergistic inhibition, which should be considered in devising strategies to alleviate this effect. Combined β-glucosidase and PEG addition at an appropriate dose was feasible to balance cost and hydrolytic efficiency. To achieve efficient hydrolysis, especially at high solid concentrations, it is important to understand the synergistic inhibition between these inhibitors.
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Affiliation(s)
- Jian Du
- College of Food Science and Pharmaceutical Engineering, Zaozhuang University, Zaozhuang 277160, China.
| | - Jingrui Liang
- College of Food Science and Pharmaceutical Engineering, Zaozhuang University, Zaozhuang 277160, China
| | - Xiujun Zhang
- College of Biological Science and Technology, Jinan University, Jinan 250024, China
| | - Jinglong Wang
- College of Food Science and Pharmaceutical Engineering, Zaozhuang University, Zaozhuang 277160, China
| | - Wei Li
- College of Food Science and Pharmaceutical Engineering, Zaozhuang University, Zaozhuang 277160, China
| | - Peixue Song
- College of City and Architectural Engineering, Zaozhuang University, Zaozhuang 277160, China
| | - Xiaohui Feng
- College of Food Science and Pharmaceutical Engineering, Zaozhuang University, Zaozhuang 277160, China
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5
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Cai Q, Hu C, Tang W, Jiang H, Geng M, Huang X, Kong X. Dietary Addition With Clostridium butyricum and Xylo-Oligosaccharides Improves Carcass Trait and Meat Quality of Huanjiang Mini-Pigs. Front Nutr 2021; 8:748647. [PMID: 34805243 PMCID: PMC8604159 DOI: 10.3389/fnut.2021.748647] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 10/05/2021] [Indexed: 12/11/2022] Open
Abstract
This study was conducted to investigate the effects of dietary addition with Clostridium butyricum (CB) and xylo-oligosaccharides (XOS) on growth performance, carcass trait, and meat quality of pigs. A total of 128 Huanjiang mini-pigs with an initial body weight of 9.5 ± 0.1 kg were randomly assigned to one of four groups. The pigs in control (Con) group were fed a basal diet and those in the experimental groups were fed the basal diet supplemented with 0.05% CB (CB group), 0.02% XOS (XOS group), or 0.05% CB + 0.02% XOS (CB + XOS group). Eight replicate pens were used per group with four pigs per pen. On days 28, 56, and 84 of the trial, the growth performance, carcass trait, and meat quality were evaluated. The results showed that dietary CB addition decreased (p < 0.05) the average daily gain and increased (p < 0.05) the ratio of feed intake to body weight gain at day 28 of the trial; CB, XOS, and CB + XOS addition increased (p < 0.05) the backfat thickness at day 84 of the trial compared with the Con group. Dietary CB, XOS, and CB + XOS addition increased (p < 0.05) the pH45min, while decreased (p < 0.05) the marbling score at day 28 of the trial compared with the Con group. Dietary CB + XOS addition increased (p < 0.05) the contents of Ala, Arg, Asp, Gly, His, Leu, Lys, Met, Phe, Ser, Thr, Tyr, and Val in muscle at day 56 of the trial. At day 84 of the trial, dietary CB addition increased the contents of nonessential amino acid (NEAA), total amino acid (TAA), and monounsaturated fatty acid (MUFA), while decreased (p < 0.05) the percentage of C20:1 in muscle compared with the Con group. Collectively, dietary addition with 0.05% CB and 0.02% XOS could not alter the growth performance, but increase carcass trait, meat quality, and muscular nutrient contents in Huanjiang mini-pigs.
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Affiliation(s)
- Qiaoli Cai
- Hunan Provincial Key Laboratory of Animal Nutrition Physiology and Metabolism Process, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, China.,College of Animal Science and Technology, Hunan Co-Innovation Center of Animal Production Safety, Hunan Agricultural University, Changsha, China
| | - Chengjun Hu
- Hunan Provincial Key Laboratory of Animal Nutrition Physiology and Metabolism Process, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, China.,Tropical Crops Genetic Resources Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou, China
| | - Wu Tang
- Hunan Provincial Key Laboratory of Animal Nutrition Physiology and Metabolism Process, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, China
| | - Huijiao Jiang
- Hunan Provincial Key Laboratory of Animal Nutrition Physiology and Metabolism Process, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, China.,College of Animal Science and Technology, Hunan Co-Innovation Center of Animal Production Safety, Hunan Agricultural University, Changsha, China
| | - Meimei Geng
- Hunan Provincial Key Laboratory of Animal Nutrition Physiology and Metabolism Process, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, China
| | - Xingguo Huang
- College of Animal Science and Technology, Hunan Co-Innovation Center of Animal Production Safety, Hunan Agricultural University, Changsha, China
| | - Xiangfeng Kong
- Hunan Provincial Key Laboratory of Animal Nutrition Physiology and Metabolism Process, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, China.,College of Animal Science and Technology, Hunan Co-Innovation Center of Animal Production Safety, Hunan Agricultural University, Changsha, China
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6
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Acid-catalyzed steam explosion for high enzymatic saccharification and low inhibitor release from lignocellulosic cardoon stalks. Biochem Eng J 2021. [DOI: 10.1016/j.bej.2021.108121] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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Haske-Cornelius O, Hartmann A, Brunner F, Pellis A, Bauer W, Nyanhongo GS, Guebitz GM. Effects of enzymes on the refining of different pulps. J Biotechnol 2020; 320:1-10. [PMID: 32553829 DOI: 10.1016/j.jbiotec.2020.06.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 05/29/2020] [Accepted: 06/09/2020] [Indexed: 11/30/2022]
Abstract
Comparative studies of the effects of two commercial enzyme formulations on fiber refining were conducted. Extensive basic characterisation of the enzymes involved, assessment of their hydrolytic activities on different model substrates as well as on different pulps (softwood sulfate, softwood sulfite, hardwood sulfate) were evaluated. Both enzyme formulations showed endoglucanase as well as some xylanase and β-glucosidase activity. In addition, Enzyme A reached a CMC end viscosity of 19.5 mPa compared to 11.1 mPa for Enzyme B. Reducing sugar release almost doubled from 695 μmol mL-1 for hardwood sulfate pulp to 1300 μmol mL-1 for softwood sulfite pulp with Enzyme B under the same conditions. Enzyme A increased the degree of refining even under non-ideal conditions from 23 °SR to up to 50 °SR. Further characterization of hand sheets, made from enzyme pre-treated and refined cellulose fibers with Enzyme A and B, showed that Enzyme A had the best effects leading to hand sheets with increased tensile strength and low air permeability. In summary, the increase in the degree of refining seen for Enzyme A correlated to higher xylanase and β-glucosidase activity and lower endoglucanase activity.
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Affiliation(s)
- Oskar Haske-Cornelius
- Institute of Environmental Biotechnology, University of Natural Resources and Life Sciences Vienna, Konrad-Lorenz-Strasse 20, 3430, Tulln an der Donau, Austria
| | - Alexandra Hartmann
- Graz University of Technology, Institute of Paper, Pulp and Fiber Technology, Inffeldgasse 23, Graz, 8010, Austria
| | - Florian Brunner
- Institute of Environmental Biotechnology, University of Natural Resources and Life Sciences Vienna, Konrad-Lorenz-Strasse 20, 3430, Tulln an der Donau, Austria
| | - Alessandro Pellis
- Institute of Environmental Biotechnology, University of Natural Resources and Life Sciences Vienna, Konrad-Lorenz-Strasse 20, 3430, Tulln an der Donau, Austria
| | - Wolfgang Bauer
- Graz University of Technology, Institute of Paper, Pulp and Fiber Technology, Inffeldgasse 23, Graz, 8010, Austria
| | - Gibson S Nyanhongo
- Institute of Environmental Biotechnology, University of Natural Resources and Life Sciences Vienna, Konrad-Lorenz-Strasse 20, 3430, Tulln an der Donau, Austria.
| | - Georg M Guebitz
- Institute of Environmental Biotechnology, University of Natural Resources and Life Sciences Vienna, Konrad-Lorenz-Strasse 20, 3430, Tulln an der Donau, Austria; Austrian Centre of Industrial Biotechnology, Konrad-Lorenz-Strasse 20, 3430, Tulln an der Donau, Austria
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8
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Biocatalysis of Industrial Kraft Pulps: Similarities and Differences between Hardwood and Softwood Pulps in Hydrolysis by Enzyme Complex of Penicillium verruculosum. Catalysts 2020. [DOI: 10.3390/catal10050536] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Kraft pulp enzymatic hydrolysis is a promising method of woody biomass bioconversion. The influence of composition and structure of kraft fibers on their hydrolysis efficiency was evaluated while using four substrates, unbleached hardwood pulp (UHP), unbleached softwood pulp (USP), bleached hardwood pulp (BHP), and bleached softwood pulp (BSP). Hydrolysis was carried out with Penicillium verruculosum enzyme complex at a dosage of 10 filter paper units (FPU)/g pulp. The changes in fiber morphology and structure were visualized while using optical and electron microscopy. Fiber cutting and swelling and quick xylan destruction were the main processes at the beginning of hydrolysis. The negative effect of lignin content was more pronounced for USP. Drying decreased the sugar yield of dissolved hydrolysis products for all kraft pulps. Fiber morphology, different xylan and mannan content, and hemicelluloses localization in kraft fibers deeply affected the hydrolyzability of bleached pulps. The introduction of additional xylobiase, mannanase, and cellobiohydrolase activities to enzyme mixture will further improve the hydrolysis of bleached pulps. A high efficiency of never-dried bleached pulp bioconversion was shown. At 10% substrate concentration, hydrolysates with more than 50 g/L sugar concentration were obtained. The bioconversion of never-dried BHP and BSP could be integrated into working kraft pulp mills.
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9
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Chen X, Zhai R, Li Y, Yuan X, Liu ZH, Jin M. Understanding the structural characteristics of water-soluble phenolic compounds from four pretreatments of corn stover and their inhibitory effects on enzymatic hydrolysis and fermentation. BIOTECHNOLOGY FOR BIOFUELS 2020; 13:44. [PMID: 32175010 PMCID: PMC7065323 DOI: 10.1186/s13068-020-01686-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Accepted: 02/22/2020] [Indexed: 06/10/2023]
Abstract
BACKGROUND For bioethanol production from lignocellulosic biomass, phenolics derived from pretreatment have been generally considered as highly inhibitory towards enzymatic hydrolysis and fermentation. As phenolics are produced from lignin degradation during pretreatment, it is likely that the pretreatment will exert a strong impact on the structure of phenolics, resulting in varied levels of inhibition of the bioconversion process. Despite the extensive studies on pretreatment, it remains unclear how pretreatment process affects the properties of generated phenolics and how the inhibitory effect of phenolics from different pretreatment varies on enzymatic hydrolysis and fermentation. RESULTS In this study, the structural properties of phenolic compounds derived from four typical pretreatment [dilute acid (DA), liquid hot water pretreatment (LHW), ammonia fiber expansion (AFEX) and alkaline pretreatment (AL)] were characterized, and their effect on both enzymatic hydrolysis and fermentation were evaluated. The inhibitory effect of phenolics on enzymatic hydrolysis followed the order: AFEX > LHW > DA > AL, while the inhibitory effect of phenolics on Zymomonas mobilis 8b strain fermentation followed the order: AL > LHW > DA > AFEX. Interestingly, this study revealed that phenolics derived from AFEX showed more severe inhibitory effect on enzymatic hydrolysis than those from the other pretreatments at the same phenolics concentrations (note: AFEX produced much less amount of phenolics compared to AL and DA), while they exhibited the lowest inhibitory effect on fermentation. The composition of phenolics from different pretreatments was analyzed and model phenolics were applied to explore the reason for this difference. The results suggested that the amide group in phenolics might account for this difference. CONCLUSIONS Pretreatment process greatly affects the properties of generated phenolics and the inhibitory effects of phenolics on enzymatic hydrolysis and fermentation. This study provides new insight for further pretreatment modification and hydrolysate detoxification to minimize phenolics-caused inhibition and enhance the efficiency of enzymatic hydrolysis and fermentation.
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Affiliation(s)
- Xiangxue Chen
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, 200 Xiaolingwei Street, Xuanwu District, Nanjing, 210094 China
| | - Rui Zhai
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, 200 Xiaolingwei Street, Xuanwu District, Nanjing, 210094 China
| | - Ying Li
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, 200 Xiaolingwei Street, Xuanwu District, Nanjing, 210094 China
| | - Xinchuan Yuan
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, 200 Xiaolingwei Street, Xuanwu District, Nanjing, 210094 China
| | - Zhi-Hua Liu
- Department of Plant Pathology and Microbiology, College of Agriculture and Life Sciences, Texas A&M University, College Station, TX 77843 USA
| | - Mingjie Jin
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, 200 Xiaolingwei Street, Xuanwu District, Nanjing, 210094 China
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Novel approach to produce biomass-derived oligosaccharides simultaneously by recombinant endoglucanase from Trichoderma reesei. Enzyme Microb Technol 2020; 134:109481. [PMID: 32044028 DOI: 10.1016/j.enzmictec.2019.109481] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Revised: 11/23/2019] [Accepted: 11/26/2019] [Indexed: 11/23/2022]
Abstract
The recombinant endoglucanase gene (EG I) from Trichoderma reesei was successfully expressed in Pichia pastoris for the purpose of producing oligosaccharides from various biomass-derived substrates. Interestingly, the recombinant endoglucanase I (ReEG I) showed the catalytic activity towards both cellulose and xylan hydrolysis, yet it was more efficient with xylans. Among various glucans and xylans substrates (paper pulp, carboxymethylated cellulose, oat spelt xylan, birchwood xylan), birchwood xylan displayed a higher yield of xylooligosaccharides (XOS) (69.5 % after optimization). Eventually, it was observed that ReEG I could simultaneously produce XOS and COS, when the alkali-extracted corncob residues were used as substrate. This is the first report on simultaneous production of XOS and COS by recombinant endoglucanase I from Trichoderma reesei expressed in Pichia pastoris, where a novel application of genetically engineered enzymes is proposed to provide an attractive application for high value utilization of biomass.
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Mohapatra S, Mishra C, Merritt BB, Pattathil S, Thatoi H. Evaluating the Role of Ultrasonication-Assisted Alkali Pretreatment and Enzymatic Hydrolysis on Cellwall Polysaccharides of Pennisetum
Grass Varieties as Potential Biofuel Feedstock. ChemistrySelect 2019. [DOI: 10.1002/slct.201802187] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Sonali Mohapatra
- Department of Biotechnology; College of Engineering and Technology; Biju Pattnaik University of Technology; Bhubaneswar- 751003 India
| | - Chinmaya Mishra
- Department of Biotechnology; College of Engineering and Technology; Biju Pattnaik University of Technology; Bhubaneswar- 751003 India
| | - Brian B Merritt
- Complex Carbohydrate Research Center; University of Georgia, GA 30602 USA and BioEnergy Science Center (BESC); Oak Ridge National Laboratory; Oak Ridge, TN 37831 USA
| | - Sivakumar Pattathil
- Complex Carbohydrate Research Center; University of Georgia, GA 30602 USA and BioEnergy Science Center (BESC); Oak Ridge National Laboratory; Oak Ridge, TN 37831 USA
| | - Hrudayanath Thatoi
- Department of Biotechnology; North Orissa University; Sriram Chandra vihar, Takatpur Baripada- 757003, Odisha India
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Xin D, Chen X, Wen P, Zhang J. Insight into the role of α-arabinofuranosidase in biomass hydrolysis: cellulose digestibility and inhibition by xylooligomers. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:64. [PMID: 30949240 PMCID: PMC6429694 DOI: 10.1186/s13068-019-1412-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Accepted: 03/15/2019] [Indexed: 05/05/2023]
Abstract
BACKGROUND α-l-Arabinofuranosidase (ARA), a debranching enzyme that can remove arabinose substituents from arabinoxylan and arabinoxylooligomers (AXOS), promotes the hydrolysis of the arabinoxylan fraction of biomass; however, the impact of ARA on the overall digestibility of cellulose is controversial. In this study, we investigated the effects of the addition of ARA on cellulase hydrolytic action. RESULTS We found that approximately 15% of the xylan was converted into AXOS during the hydrolysis of aqueous ammonia-pretreated corn stover and that this AXOS fraction was approximately 12% substituted with arabinose. The addition of ARA removes a portion of the arabinose decoration, but the resulting less-substituted AXOS inhibited cellulase action much more effectively; showing an increase of 45.7%. Kinetic experiments revealed that AXOS with a lower degree of arabinose substitution showed stronger affinity for the active site of cellobiohydrolase, which could be the mechanism of increased inhibition. CONCLUSIONS Our findings strongly suggest that the ratio of ARA and other xylanases should be carefully selected to avoid the strong inhibition caused by the less-substituted AXOS during the hydrolysis of arabinoxylan-containing biomass. This study advances our understanding of the inhibitory mechanism of xylooligomers and provides critical new insights into the relationship of ARA addition and cellulose digestibility.
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Affiliation(s)
- Donglin Xin
- College of Forestry, Northwest A&F University, 3 Taicheng Road, Yangling, 712100 Shaanxi China
| | - Xiang Chen
- College of Forestry, Northwest A&F University, 3 Taicheng Road, Yangling, 712100 Shaanxi China
| | - Peiyao Wen
- College of Forestry, Northwest A&F University, 3 Taicheng Road, Yangling, 712100 Shaanxi China
| | - Junhua Zhang
- College of Forestry, Northwest A&F University, 3 Taicheng Road, Yangling, 712100 Shaanxi China
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Rahmani N, Kahar P, Lisdiyanti P, Hermiati E, Lee J, Yopi, Prasetya B, Ogino C, Kondo A. Xylanase and feruloyl esterase from actinomycetes cultures could enhance sugarcane bagasse hydrolysis in the production of fermentable sugars. Biosci Biotechnol Biochem 2018; 82:1-12. [PMID: 29475403 DOI: 10.1080/09168451.2018.1438169] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Accepted: 01/30/2018] [Indexed: 10/18/2022]
Abstract
The addition of enzymes that are capable of degrading hemicellulose has a potential to reduce the need for commercial enzymes during biomass hydrolysis in the production of fermentable sugars. In this study, a high xylanase producing actinomycete strain (Kitasatospora sp. ID06-480) and the first ethyl ferulate producing actinomycete strain (Nonomuraea sp. ID06-094) were selected from 797 rare actinomycetes, respectively, which were isolated in Indonesia. The addition (30%, v/v) of a crude enzyme supernatant from the selected strains in sugarcane bagasse hydrolysis with low-level loading (1 FPU/g-biomass) of Cellic® CTec2 enhanced both the released amount of glucose and reducing sugars. When the reaction with Ctec2 was combined with crude enzymes containing either xylanase or feruloyl esterase, high conversion yield of glucose from cellulose at 60.5% could be achieved after 72 h-saccharification.
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Affiliation(s)
- Nanik Rahmani
- a Research Center for Biotechnology , Indonesian Institute of Sciences, Cibinong Science Center , Cibinong , Indonesia
| | - Prihardi Kahar
- b Department of Chemical and Engineering, Graduate School of Engineering , Kobe University , Kobe , Japan
| | - Puspita Lisdiyanti
- a Research Center for Biotechnology , Indonesian Institute of Sciences, Cibinong Science Center , Cibinong , Indonesia
| | - Euis Hermiati
- c Research Center for Biomaterial , Indonesian Institute of Sciences, Cibinong Science Center , Cibinong , Indonesia
| | - Jaemin Lee
- b Department of Chemical and Engineering, Graduate School of Engineering , Kobe University , Kobe , Japan
| | - Yopi
- a Research Center for Biotechnology , Indonesian Institute of Sciences, Cibinong Science Center , Cibinong , Indonesia
| | - Bambang Prasetya
- a Research Center for Biotechnology , Indonesian Institute of Sciences, Cibinong Science Center , Cibinong , Indonesia
- d National Standardization Agency of Indonesia, Gedung I BPPT , Jakarta , Indonesia
| | - Chiaki Ogino
- b Department of Chemical and Engineering, Graduate School of Engineering , Kobe University , Kobe , Japan
| | - Akihiko Kondo
- b Department of Chemical and Engineering, Graduate School of Engineering , Kobe University , Kobe , Japan
- e Graduate School of Science, Technology and Innovation , Kobe University , Kobe , Japan
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Immobilization and Stabilization of Beta-Xylosidases from Penicillium janczewskii. Appl Biochem Biotechnol 2016; 182:349-366. [DOI: 10.1007/s12010-016-2331-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Accepted: 11/10/2016] [Indexed: 01/08/2023]
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Terrasan CRF, Aragon CC, Masui DC, Pessela BC, Fernandez-Lorente G, Carmona EC, Guisan JM. β-xylosidase from Selenomonas ruminantium: Immobilization, stabilization, and application for xylooligosaccharide hydrolysis. BIOCATAL BIOTRANSFOR 2016. [DOI: 10.1080/10242422.2016.1247817] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- César Rafael Fanchini Terrasan
- Departamento de Biocatálisis, Instituto de Catálisis y Petroleoquimica (ICP), Consejo Superior de Investigaciones Científicas (CSIC), Campus Universidad Autónoma de Madrid (UAM), Madrid, Spain,
| | - Caio Casale Aragon
- Departamento de Biocatálisis, Instituto de Catálisis y Petroleoquimica (ICP), Consejo Superior de Investigaciones Científicas (CSIC), Campus Universidad Autónoma de Madrid (UAM), Madrid, Spain,
| | - Douglas Chodi Masui
- Departamento de Biocatálisis, Instituto de Catálisis y Petroleoquimica (ICP), Consejo Superior de Investigaciones Científicas (CSIC), Campus Universidad Autónoma de Madrid (UAM), Madrid, Spain,
| | - Benevides Costa Pessela
- Departamento de Biotecnología y Microbiología de Alimentos, Instituto de Investigación en Ciencias de los Alimentos (CIAL), Consejo Superior de Investigaciones Científicas (CSIC), Campus Universidad Autónoma de Madrid (UAM), Madrid, Spain, and
| | - Gloria Fernandez-Lorente
- Departamento de Biotecnología y Microbiología de Alimentos, Instituto de Investigación en Ciencias de los Alimentos (CIAL), Consejo Superior de Investigaciones Científicas (CSIC), Campus Universidad Autónoma de Madrid (UAM), Madrid, Spain, and
| | - Eleonora Cano Carmona
- Biochemistry and Microbiology Department, Biosciences Institute, Univ Estadual Paulista – UNESP, Rio Claro, São Paulo, Brazil
| | - Jose Manuel Guisan
- Departamento de Biocatálisis, Instituto de Catálisis y Petroleoquimica (ICP), Consejo Superior de Investigaciones Científicas (CSIC), Campus Universidad Autónoma de Madrid (UAM), Madrid, Spain,
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16
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Wang X, Li K, Yang M, Zhang J. Hydrolyzability of xylan after adsorption on cellulose: Exploration of xylan limitation on enzymatic hydrolysis of cellulose. Carbohydr Polym 2016; 148:362-70. [PMID: 27185150 DOI: 10.1016/j.carbpol.2016.04.069] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Revised: 03/20/2016] [Accepted: 04/17/2016] [Indexed: 11/19/2022]
Abstract
During pretreatment of lignocellulosic materials, the dissolved xylan would re-adsorb on cellulose, and then inhibits the cellulose hydrolysis by cellulases. However, the hydrolyzability of xylan adsorbed on cellulose is not clear. In this work, the adsorption behavior of xylans on celluloses and the hydrolysis of adsorbed xylan by xylanase (XYL) were investigated. The results indicated that the adsorption of beechwood xylan (BWX) and oat spelt xylan (OSX) on Avicel was conformed to Langmuir-type adsorption isotherm. Higher ion strength increased the adsorption of BWX on Avicel, but not that of OSX. Both BWX and OSX adsorbed on Avicel and corn stover after dilute acid pretreatment (CS-DA) could be hydrolyzed by XYL. Compared to OSX, BWX adsorbed on cellulosic materials could be more easily hydrolyzed by XYL. Thus, supplementation of XYL could hydrolyze the xylan adsorbed on cellulose and potentially improved hydrolysis efficiency of lignocelluloses.
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Affiliation(s)
- Xiao Wang
- College of Forestry, Northwest A&F University, 3 Taicheng Road, Yangling 712100, China
| | - Kena Li
- College of Forestry, Northwest A&F University, 3 Taicheng Road, Yangling 712100, China
| | - Ming Yang
- College of Forestry, Northwest A&F University, 3 Taicheng Road, Yangling 712100, China
| | - Junhua Zhang
- College of Forestry, Northwest A&F University, 3 Taicheng Road, Yangling 712100, China.
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17
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Méndez Arias J, Modesto LFA, Polikarpov I, Pereira N. Design of an enzyme cocktail consisting of different fungal platforms for efficient hydrolysis of sugarcane bagasse: Optimization and synergism studies. Biotechnol Prog 2016; 32:1222-1229. [DOI: 10.1002/btpr.2306] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 05/10/2016] [Indexed: 11/11/2022]
Affiliation(s)
- Johanna Méndez Arias
- Laboratórios de Desenvolvimento de Bioprocessos, Departamento de Engenharia Bioquímica; Escola de Química, Universidade Federal do Rio de Janeiro; Rio de Janeiro 21949-900 Brazil
| | - Luiz Felipe Amarante Modesto
- Laboratórios de Desenvolvimento de Bioprocessos, Departamento de Engenharia Bioquímica; Escola de Química, Universidade Federal do Rio de Janeiro; Rio de Janeiro 21949-900 Brazil
| | - Igor Polikarpov
- Instituto de Física de São Carlos, Departamento de Física e Ciência Interdisciplinar; Universidade de São Paulo; São Paulo Brazil
| | - Nei Pereira
- Laboratórios de Desenvolvimento de Bioprocessos, Departamento de Engenharia Bioquímica; Escola de Química, Universidade Federal do Rio de Janeiro; Rio de Janeiro 21949-900 Brazil
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18
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Bischof RH, Ramoni J, Seiboth B. Cellulases and beyond: the first 70 years of the enzyme producer Trichoderma reesei. Microb Cell Fact 2016; 15:106. [PMID: 27287427 PMCID: PMC4902900 DOI: 10.1186/s12934-016-0507-6] [Citation(s) in RCA: 280] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Accepted: 06/01/2016] [Indexed: 11/10/2022] Open
Abstract
More than 70 years ago, the filamentous ascomycete Trichoderma reesei was isolated on the Solomon Islands due to its ability to degrade and thrive on cellulose containing fabrics. This trait that relies on its secreted cellulases is nowadays exploited by several industries. Most prominently in biorefineries which use T. reesei enzymes to saccharify lignocellulose from renewable plant biomass in order to produce biobased fuels and chemicals. In this review we summarize important milestones of the development of T. reesei as the leading production host for biorefinery enzymes, and discuss emerging trends in strain engineering. Trichoderma reesei has very recently also been proposed as a consolidated bioprocessing organism capable of direct conversion of biopolymeric substrates to desired products. We therefore cover this topic by reviewing novel approaches in metabolic engineering of T. reesei.
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Affiliation(s)
- Robert H Bischof
- Austrian Centre of Industrial Biotechnology (ACIB) GmbH c/o Institute of Chemical Engineering, TU Wien, Gumpendorferstraße 1a, 1060, Vienna, Austria
| | - Jonas Ramoni
- Molecular Biotechnology, Research Area Biochemical Technology, Institute of Chemical Engineering, TU Wien, Gumpendorferstraße 1a, 1060, Vienna, Austria
| | - Bernhard Seiboth
- Austrian Centre of Industrial Biotechnology (ACIB) GmbH c/o Institute of Chemical Engineering, TU Wien, Gumpendorferstraße 1a, 1060, Vienna, Austria. .,Molecular Biotechnology, Research Area Biochemical Technology, Institute of Chemical Engineering, TU Wien, Gumpendorferstraße 1a, 1060, Vienna, Austria.
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19
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Contrasted enzymatic cocktails reveal the importance of cellulases and hemicellulases activity ratios for the hydrolysis of cellulose in presence of xylans. AMB Express 2016; 6:24. [PMID: 27001439 PMCID: PMC4801825 DOI: 10.1186/s13568-016-0196-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Accepted: 03/11/2016] [Indexed: 11/18/2022] Open
Abstract
Various enzymatic cocktails were produced from two Trichoderma reesei strains, a cellulase hyperproducer strain and a strain with β-glucosidase activity overexpression. By using various carbon sources (lactose, glucose, xylose, hemicellulosic hydrolysate) for strains growth, contrasted enzymatic activities were obtained. The enzymatic cocktails presented various levels of efficiency for the hydrolysis of cellulose Avicel into glucose, in presence of xylans, or not. These latter were also hydrolyzed with different extents according to cocktails. The most efficient cocktails (TR1 and TR3) on Avicel were richer in filter paper activity (FPU) and presented a low ratio FPU/β-glucosidase activity. Cocktails TR2 and TR5 which were produced on the higher amount of hemicellulosic hydrolysate, possess both high xylanase and β-xylosidase activities, and were the most efficient for xylans hydrolysis. When hydrolysis of Avicel was conducted in presence of xylans, a decrease of glucose release occurred for all cocktails compared to hydrolysis of Avicel alone. Mixing TR1 and TR5 cocktails with two different ratios of proteins (1/1 and 1/4) resulted in a gain of efficiency for glucose release during hydrolysis of Avicel in presence of xylans compared to TR5 alone. Our results demonstrate the importance of combining hemicellulase and cellulase activities to improve the yields of glucose release from Avicel in presence of xylans. In this context, strategies involving enzymes production with carbon sources comprising mixed C5 and C6 sugars or combining different cocktails produced on C5 or on C6 sugars are of interest for processes developed in the context of lignocellulosic biorefinery.
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20
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Zakaria MR, Hirata S, Fujimoto S, Ibrahim I, Hassan MA. Soluble inhibitors generated during hydrothermal pretreatment of oil palm mesocarp fiber suppressed the catalytic activity of Acremonium cellulase. BIORESOURCE TECHNOLOGY 2016; 200:541-547. [PMID: 26524253 DOI: 10.1016/j.biortech.2015.10.075] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Revised: 10/20/2015] [Accepted: 10/22/2015] [Indexed: 06/05/2023]
Abstract
Oil palm mesocarp fiber was subjected to hydrothermal pretreatment under isothermal and non-isothermal conditions. The pretreated slurries were separated by filtration, pretreated liquids and solids were characterized. An enzymatic digestibility study was performed for both pretreated slurries and solids to understand the effect of soluble inhibitors generated during the pretreatment process. The highest glucose yield obtained from pretreated slurries was 70.1%, and gradually decreased with higher pretreatment severities. The highest glucose yield obtained in pretreated solids was 100%, after pretreatment at 210°C for 20min. In order to study the inhibitory effects of compounds generated during pretreatment with cellulase, technical grade solutions that mimic the pretreated liquid were prepared and their effect on Acremonium cellulase activity was monitored using Avicel. Xylo-oligomers and tannic acid were identified as powerful inhibitors of Acremonium cellulase, and the lowest hydrolysis rate of Avicel of 0.18g/g-glucose released/L/h was obtained from tannic acid.
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Affiliation(s)
- Mohd Rafein Zakaria
- Research Institute for Sustainable Chemistry, National Institute of Advanced Industrial Science and Technology (AIST), 3-11-32 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-0046, Japan; Department of Bioprocess Technology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
| | - Satoshi Hirata
- Department of Materials and Chemistry, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568, Japan
| | - Shinji Fujimoto
- Research Institute for Sustainable Chemistry, National Institute of Advanced Industrial Science and Technology (AIST), 3-11-32 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-0046, Japan
| | - Izzudin Ibrahim
- Department of Bioprocess Technology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
| | - Mohd Ali Hassan
- Department of Bioprocess Technology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia; Department of Process and Food Engineering, Faculty of Engineering, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
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21
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Xin D, Yang M, Chen X, Zhang J. The access of Trichoderma reesei 6A to cellulose is blocked by isolated hemicelluloses and their derivatives in biomass hydrolysis. RSC Adv 2016. [DOI: 10.1039/c6ra14617a] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Mannan inhibited action of CBHII from Trichoderma reesei by retarding the adsorption of CBHII to cellulose.
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Affiliation(s)
- Donglin Xin
- College of Forestry
- Northwest A&F University
- Yangling 712100
- China
| | - Ming Yang
- College of Forestry
- Northwest A&F University
- Yangling 712100
- China
| | - Xiang Chen
- College of Forestry
- Northwest A&F University
- Yangling 712100
- China
| | - Junhua Zhang
- College of Forestry
- Northwest A&F University
- Yangling 712100
- China
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22
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Gonçalves GA, Takasugi Y, Jia L, Mori Y, Noda S, Tanaka T, Ichinose H, Kamiya N. Synergistic effect and application of xylanases as accessory enzymes to enhance the hydrolysis of pretreated bagasse. Enzyme Microb Technol 2015; 72:16-24. [DOI: 10.1016/j.enzmictec.2015.01.007] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Revised: 12/16/2014] [Accepted: 01/19/2015] [Indexed: 11/30/2022]
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23
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Momeni MH, Ubhayasekera W, Sandgren M, Ståhlberg J, Hansson H. Structural insights into the inhibition of cellobiohydrolase Cel7A by xylo-oligosaccharides. FEBS J 2015; 282:2167-77. [PMID: 25765184 DOI: 10.1111/febs.13265] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2015] [Revised: 03/06/2015] [Accepted: 03/10/2015] [Indexed: 11/28/2022]
Abstract
UNLABELLED The filamentous fungus Hypocrea jecorina (anamorph of Trichoderma reesei) is the predominant source of enzymes for industrial saccharification of lignocellulose biomass. The major enzyme, cellobiohydrolase Cel7A, constitutes nearly half of the total protein in the secretome. The performance of such enzymes is susceptible to inhibition by compounds liberated by physico-chemical pre-treatment if the biomass is kept unwashed. Xylan and xylo-oligosaccharides (XOS) have been proposed to play a key role in inhibition of cellobiohydrolases of glycoside hydrolase family 7. To elucidate the mechanism behind this inhibition at a molecular level, we used X-ray crystallography to determine structures of H. jecorina Cel7A in complex with XOS. Structures with xylotriose, xylotetraose and xylopentaose revealed a predominant binding mode at the entrance of the substrate-binding tunnel of the enzyme, in which each xylose residue is shifted ~ 2.4 Å towards the catalytic center compared with binding of cello-oligosaccharides. Furthermore, partial occupancy of two consecutive xylose residues at subsites -2 and -1 suggests an alternative binding mode for XOS in the vicinity of the catalytic center. Interestingly, the -1 xylosyl unit exhibits an open aldehyde conformation in one of the structures and a ring-closed pyranoside in another complex. Complementary inhibition studies with p-nitrophenyl lactoside as substrate indicate mixed inhibition rather than pure competitive inhibition. DATABASE The atomic coordinates and structure factors are available in the Protein Data Bank under accession number 4D5I (H. jecorina Cel7A E212Q variant, complex with xylotriose), 4D5J (H. jecorina Cel7A E217Q variant, complex with xylotriose), 4D5O (H. jecorina Cel7A E212Q variant, complex with xylopentaose), 4D5P (H. jecorina Cel7A E217Q variant, complex with xylopentaose), 4D5Q (wild-type H. jecorina Cel7A, complex with xylopentaose) and 4D5V (H. jecorina Cel7A E217Q variant, complex with xylotetraose).
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Affiliation(s)
- Majid Haddad Momeni
- Department of Chemistry and Biotechnology, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Wimal Ubhayasekera
- Institute of Medicinal Chemistry, University of Copenhagen, Denmark.,MAX-Lab, Lund University, Sweden
| | - Mats Sandgren
- Department of Chemistry and Biotechnology, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Jerry Ståhlberg
- Department of Chemistry and Biotechnology, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Henrik Hansson
- Department of Chemistry and Biotechnology, Swedish University of Agricultural Sciences, Uppsala, Sweden
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24
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Kapoor RK, Rajan K, Carrier DJ. Applications of Trametes versicolor crude culture filtrates in detoxification of biomass pretreatment hydrolyzates. BIORESOURCE TECHNOLOGY 2015; 189:99-106. [PMID: 25876229 DOI: 10.1016/j.biortech.2015.03.100] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Revised: 03/20/2015] [Accepted: 03/21/2015] [Indexed: 06/04/2023]
Abstract
Laccases have wide range of substrate specificity and find applications from pulp industry to waste water remediation. Laccases have also been used in combined pretreatment of biomass hydrolyzates to remove enzymatic and fermentation inhibitors. In this study, laccase production by Trametes versicolor strains isolated from different regions of the United States was induced using copper salts. T. versicolor crude culture filtrates (CCF), without any purification step, were tested for removal of model inhibitor compounds as well as in poplar and rice straw pretreatment hydrolyzates. Phenolic inhibitors were removed by 76% and 94% from the dilute acid hydrolyzates of rice straw and poplar, respectively, when incubated with the CCF for 12h, at room temperature. Xylo-oligosaccharide concentrations present in rice straw hydrolyzates were reduced by 64% when incubated with T. versicolor CCF. T. versicolor CCF could be a low cost technology for decreasing enzymatic and fermentation inhibitors.
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Affiliation(s)
- Rajeev Kumar Kapoor
- Department of Microbiology, Maharshi Dayanand University, Rohtak, Haryana, India
| | - Kalavathy Rajan
- Department of Food Science, University of Arkansas, 2650 N Young Ave, Fayetteville, AR 72704, USA
| | - Danielle Julie Carrier
- Department of Biological and Agricultural Engineering, 203 White Engineering Hall, 1 University of Arkansas, Fayetteville, AR 72701, USA.
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25
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Xue S, Uppugundla N, Bowman MJ, Cavalier D, Da Costa Sousa L, E Dale B, Balan V. Sugar loss and enzyme inhibition due to oligosaccharide accumulation during high solids-loading enzymatic hydrolysis. BIOTECHNOLOGY FOR BIOFUELS 2015; 8:195. [PMID: 26617670 PMCID: PMC4662034 DOI: 10.1186/s13068-015-0378-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Accepted: 11/09/2015] [Indexed: 05/03/2023]
Abstract
BACKGROUND Accumulation of recalcitrant oligosaccharides during high-solids loading enzymatic hydrolysis of cellulosic biomass reduces biofuel yields and increases processing costs for a cellulosic biorefinery. Recalcitrant oligosaccharides in AFEX-pretreated corn stover hydrolysate accumulate to the extent of about 18-25 % of the total soluble sugars in the hydrolysate and 12-18 % of the total polysaccharides in the inlet biomass (untreated), equivalent to a yield loss of about 7-9 kg of monomeric sugars per 100 kg of inlet dry biomass (untreated). These oligosaccharides represent a yield loss and also inhibit commercial hydrolytic enzymes, with both being serious bottlenecks for economical biofuel production from cellulosic biomass. Very little is understood about the nature of these oligomers and why they are recalcitrant to commercial enzymes. This work presents a robust method for separating recalcitrant oligosaccharides from high solid loading hydrolysate in gramme quantities. Composition analysis, recalcitrance study and enzyme inhibition study were performed to understand their chemical nature. RESULTS Oligosaccharide accumulation occurs during high solid loading enzymatic hydrolysis of corn stover (CS) irrespective of using different pretreated corn stover (dilute acid: DA, ionic liquids: IL, and ammonia fibre expansion: AFEX). The methodology for large-scale separation of recalcitrant oligosaccharides from 25 % solids-loading AFEX-corn stover hydrolysate using charcoal fractionation and size exclusion chromatography is reported for the first time. Oligosaccharides with higher degree of polymerization (DP) were recalcitrant towards commercial enzyme mixtures [Ctec2, Htec2 and Multifect pectinase (MP)] compared to lower DP oligosaccharides. Enzyme inhibition studies using processed substrates (Avicel and xylan) showed that low DP oligosaccharides also inhibit commercial enzymes. Addition of monomeric sugars to oligosaccharides increases the inhibitory effects of oligosaccharides on commercial enzymes. CONCLUSION The carbohydrate composition of the recalcitrant oligosaccharides, ratios of different DP oligomers and their distribution profiles were determined. Recalcitrance and enzyme inhibition studies help determine whether the commercial enzyme mixtures lack the enzyme activities required to completely de-polymerize the plant cell wall. Such studies clarify the reasons for oligosaccharide accumulation and contribute to strategies by which oligosaccharides can be converted into fermentable sugars and provide higher biofuel yields with less enzyme.
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Affiliation(s)
- Saisi Xue
- />DOE Great Lakes Bioenergy Research Center, Biomass Conversion Research Lab (BCRL), Chemical Engineering and Materials Science, Michigan State University, 3815 Technology Boulevard, Lansing, MI 48910 USA
| | - Nirmal Uppugundla
- />DOE Great Lakes Bioenergy Research Center, Biomass Conversion Research Lab (BCRL), Chemical Engineering and Materials Science, Michigan State University, 3815 Technology Boulevard, Lansing, MI 48910 USA
| | - Michael J. Bowman
- />USDA, Agricultural Research Service, National Center for Agricultural Utilization Research, Bioenergy Research Unit, Peoria, IL 61604 USA
| | - David Cavalier
- />DOE Great Lakes Bioenergy Research Center, Biomass Conversion Research Lab (BCRL), Chemical Engineering and Materials Science, Michigan State University, 3815 Technology Boulevard, Lansing, MI 48910 USA
- />DOE Plant Research Laboratory, Michigan State University, East Lansing, MI 48824 USA
| | - Leonardo Da Costa Sousa
- />DOE Great Lakes Bioenergy Research Center, Biomass Conversion Research Lab (BCRL), Chemical Engineering and Materials Science, Michigan State University, 3815 Technology Boulevard, Lansing, MI 48910 USA
| | - Bruce. E Dale
- />DOE Great Lakes Bioenergy Research Center, Biomass Conversion Research Lab (BCRL), Chemical Engineering and Materials Science, Michigan State University, 3815 Technology Boulevard, Lansing, MI 48910 USA
| | - Venkatesh Balan
- />DOE Great Lakes Bioenergy Research Center, Biomass Conversion Research Lab (BCRL), Chemical Engineering and Materials Science, Michigan State University, 3815 Technology Boulevard, Lansing, MI 48910 USA
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26
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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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27
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Engineering Neurospora crassa for improved cellobiose and cellobionate production. Appl Environ Microbiol 2014; 81:597-603. [PMID: 25381238 DOI: 10.1128/aem.02885-14] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
We report engineering Neurospora crassa to improve the yield of cellobiose and cellobionate from cellulose. A previously engineered strain of N. crassa (F5) with six of seven β-glucosidase (bgl) genes knocked out was shown to produce cellobiose and cellobionate directly from cellulose without the addition of exogenous cellulases. In this study, the F5 strain was further modified to improve the yield of cellobiose and cellobionate from cellulose by increasing cellulase production and decreasing product consumption. The effects of two catabolite repression genes, cre-1 and ace-1, on cellulase production were investigated. The F5 Δace-1 mutant showed no improvement over the wild type. The F5 Δcre-1 and F5 Δace-1 Δcre-1 strains showed improved cellobiose dehydrogenase and exoglucanase expression. However, this improvement in cellulase expression did not lead to an improvement in cellobiose or cellobionate production. The cellobionate phosphorylase gene (ndvB) was deleted from the genome of F5 Δace-1 Δcre-1 to prevent the consumption of cellobiose and cellobionate. Despite a slightly reduced hydrolysis rate, the F5 Δace-1 Δcre-1 ΔndvB strain converted 75% of the cellulose consumed to the desired products, cellobiose and cellobionate, compared to 18% converted by the strain F5 Δace-1 Δcre-1.
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28
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Xin D, Ge X, Sun Z, Viikari L, Zhang J. Competitive inhibition of cellobiohydrolase I by manno-oligosaccharides. Enzyme Microb Technol 2014; 68:62-8. [PMID: 25435507 DOI: 10.1016/j.enzmictec.2014.09.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2014] [Revised: 08/14/2014] [Accepted: 09/20/2014] [Indexed: 10/24/2022]
Abstract
In the hydrolysis of softwood, significant amounts of manno-oligosaccharides (MOS) are released from mannan, the major hemicelluloses in softwood. However, the impact of MOS on the performance of cellulases is not yet clear. In this work, the effect of mannan and MOS in cellulose hydrolysis by cellulases, especially cellobiohydrolase I (CBHI) from Thermoascus aurantiacus (Ta Cel7A), was studied. The glucose yield of Avicel decreased with an increasing amount of added mannan. Commercial cellulases contained mannan hydrolysing enzymes, and β-glucosidase played an important role in mannan hydrolysis. Addition of 10mg/ml mannan reduced the glucose yield of Avicel (at 20g/l) from 40.1 to 24.3%. No inhibition of β-glucosidase by mannan was observed. The negative effects of mannan and MOS on the hydrolytic action of cellulases indicated that the inhibitory effect was at least partly attributed to the inhibition of Ta Cel7A (CBHI), but not on β-glucosidase. Kinetic experiments showed that MOS were competitive inhibitors of the CBHI from T. aurantiacus, and mannobiose had a stronger inhibitory effect on CBHI than mannotriose or mannotetraose. For efficient hydrolysis of softwood, it was necessary to add supplementary enzymes to hydrolyze both mannan and MOS to less inhibitory product, mannose.
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Affiliation(s)
- Donglin Xin
- College of Forestry, Northwest A&F University, 3 Taicheng Road, Yangling 712100, China
| | - Xiaoyan Ge
- College of Forestry, Northwest A&F University, 3 Taicheng Road, Yangling 712100, China
| | - Zongping Sun
- College of Forestry, Northwest A&F University, 3 Taicheng Road, Yangling 712100, China
| | - Liisa Viikari
- Department of Food and Environmental Sciences, University of Helsinki, P.O. Box 27, FIN 00014 Helsinki, Finland
| | - Junhua Zhang
- College of Forestry, Northwest A&F University, 3 Taicheng Road, Yangling 712100, China.
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Behavior of Cellulose and Xylan in Aqueous Ammonia Pretreatment. Appl Biochem Biotechnol 2014; 174:2626-38. [DOI: 10.1007/s12010-014-1214-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2014] [Accepted: 08/27/2014] [Indexed: 11/25/2022]
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Impact of Xylan on Synergistic Effects of Xylanases and Cellulases in Enzymatic Hydrolysis of Lignocelluloses. Appl Biochem Biotechnol 2014; 174:1393-1402. [DOI: 10.1007/s12010-014-1140-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Accepted: 08/01/2014] [Indexed: 10/24/2022]
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MALDI-TOF MS analysis of cellodextrins and xylo-oligosaccharides produced by hindgut homogenates of Reticulitermes santonensis. Molecules 2014; 19:4578-94. [PMID: 24731986 PMCID: PMC6270808 DOI: 10.3390/molecules19044578] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Revised: 04/02/2014] [Accepted: 04/04/2014] [Indexed: 12/03/2022] Open
Abstract
Hindgut homogenates of the termite Reticulitermes santonensis were incubated with carboxymethyl cellulose (CMC), crystalline celluloses or xylan substrates. Hydrolysates were analyzed with matrix-assisted laser desorption/ionization coupled to time-of-flight mass spectrometry (MALDI-TOF MS). The method was first set up using acid hydrolysis analysis to characterize non-enzymatic profiles. Commercial enzymes of Trichoderma reesei or T. longibrachiatum were also tested to validate the enzymatic hydrolysis analysis. For CMC hydrolysis, data processing and visual display were optimized to obtain comprehensive profiles and allow rapid comparison and evaluation of enzymatic selectivity, according to the number of substituents of each hydrolysis product. Oligosaccharides with degrees of polymerization (DPs) ranging from three to 12 were measured from CMC and the enzymatic selectivity was demonstrated. Neutral and acidic xylo-oligosaccharides with DPs ranging from three to 11 were measured from xylan substrate. These results are of interest for lignocellulose biomass valorization and demonstrated the potential of termites and their symbiotic microbiota as a source of interesting enzymes for oligosaccharides production.
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Skovgaard PA, Thygesen LG, Jørgensen H, Cardona M, Tozzi E, McCarthy M, Siika-Aho M, Jeoh T. The role of endoglucanase and endoxylanase in liquefaction of hydrothermally pretreated wheat straw. Biotechnol Prog 2014; 30:923-31. [PMID: 24610675 DOI: 10.1002/btpr.1893] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2013] [Revised: 01/18/2014] [Indexed: 11/12/2022]
Abstract
The role of endocellulases and endoxylanase during liquefaction and saccharification of hydrothermally pretreated wheat straw was studied. The use of a flow-loop setup with in-line magnetic resonance imaging enabled frequent measurements of viscosity at 55°C during saccharification at 6% total solids content. Viscosity data were complemented with off-line measurements of fiber lengths and release of soluble sugars. A clear correlation between fiber attrition and a decrease in viscosity was found. Fiber lengths and viscosity dropped quickly within the first hour and then stagnated, while sugar yields increased substantially thereafter, illustrating that liquefaction and saccharification are separate mechanisms. Both endoglucanase and endoxylanase were shown to have a significant effect on viscosity during liquefaction while the addition of endoxylanase also increased sugar yield.
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33
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Recovery of cellulase activity after ethanol stripping in a novel pilot-scale unit. J Ind Microbiol Biotechnol 2014; 41:637-46. [PMID: 24549412 DOI: 10.1007/s10295-014-1413-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2013] [Accepted: 01/30/2014] [Indexed: 11/27/2022]
Abstract
Recycling of enzymes has a potential interest during cellulosic bioethanol production as purchasing enzymes is one of the largest expenses in the process. By recycling enzymes after distillation, loss of sugars and ethanol are avoided, but depending on the distillation temperature, there is a potential risk of enzyme degradation. Studies of the rate of enzyme denaturation based on estimation of the denaturation constant K D was performed using a novel distillation setup allowing stripping of ethanol at 50-65 °C. Experiments were performed in a pilot-scale stripper, where the effect of temperature (55-65 °C) and exposure to gas-liquid and liquid-heat transmission interfaces were tested on a mesophilic and thermostable enzyme mixture in fiber beer and buffer. Lab-scale tests were included in addition to the pilot-scale experiments to study the effect of shear, ethanol concentration, and PEG on enzyme stability. When increasing the temperature (up to 65 °C) or ethanol content (up to 7.5 % w/v), the denaturation rate of the enzymes increased. Enzyme denaturation occurred slower when the experiments were performed in fiber beer compared to buffer only, which could be due to PEG or other stabilizing substances in fiber beer. However, at extreme conditions with high temperature (65 °C) and ethanol content (7.5 % w/v), PEG had no enzyme stabilizing effect. The novel distillation setup proved to be useful for maintaining enzyme activity during ethanol extraction.
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Kont R, Kurašin M, Teugjas H, Väljamäe P. Strong cellulase inhibitors from the hydrothermal pretreatment of wheat straw. BIOTECHNOLOGY FOR BIOFUELS 2013; 6:135. [PMID: 24053778 PMCID: PMC3849272 DOI: 10.1186/1754-6834-6-135] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Accepted: 09/13/2013] [Indexed: 05/03/2023]
Abstract
BACKGROUND The use of the enzymatic hydrolysis of lignocellulose with subsequent fermentation to ethanol provides a green alternative for the production of transportation fuels. Because of its recalcitrant nature, the lignocellulosic biomass must be pretreated before enzymatic hydrolysis. However, the pretreatment often results in the formation of compounds that are inhibitory for the enzymes or fermenting organism. Although well recognized, little quantitative information on the inhibition of individual cellulase components by identified inhibitors is available. RESULTS Strong cellulase inhibitors were separated from the liquid fraction of the hydrothermal pretreatment of wheat straw. HPLC and mass-spectroscopy analyses confirmed that the inhibitors were oligosaccharides (inhibitory oligosaccharides, IOS) with a degree of polymerization from 7 to 16. The IOS are composed of a mixture of xylo- (XOS) and gluco-oligosaccharides (GOS). We propose that XOS and GOS are the fragments of the xylan backbone and mixed-linkage β-glucans, respectively. The IOS were approximately 100 times stronger inhibitors for Trichoderma reesei cellobiohydrolases (CBHs) than cellobiose, which is one of the strongest inhibitors of these enzymes reported to date. Inhibition of endoglucanases (EGs) by IOS was weaker than that of CBHs. Most of the tested cellulases and hemicellulases were able to slowly degrade IOS and reduce the inhibitory power of the liquid fraction to some extent. The most efficient single enzyme component here was T. reesei EG TrCel7B. Although reduced by the enzyme treatment, the residual inhibitory power of IOS and the liquid fraction was strong enough to silence the major component of the T. reesei cellulase system, CBH TrCel7A. CONCLUSIONS The cellulase inhibitors described here may be responsible for the poor yields from the enzymatic conversion of the whole slurries from lignocellulose pretreatment under conditions that do not favor complete degradation of hemicellulose. Identification of the inhibitory compounds helps to design better enzyme mixtures for their degradation and to optimize the pretreatment regimes to minimize their formation.
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Affiliation(s)
- Riin Kont
- Institute of Molecular and Cell Biology, University of Tartu, Riia 23b - 202, 51010 Tartu, Estonia
| | - Mihhail Kurašin
- Institute of Molecular and Cell Biology, University of Tartu, Riia 23b - 202, 51010 Tartu, Estonia
| | - Hele Teugjas
- Institute of Molecular and Cell Biology, University of Tartu, Riia 23b - 202, 51010 Tartu, Estonia
| | - Priit Väljamäe
- Institute of Molecular and Cell Biology, University of Tartu, Riia 23b - 202, 51010 Tartu, Estonia
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35
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Zhang J, Tang M, Viikari L. Xylans inhibit enzymatic hydrolysis of lignocellulosic materials by cellulases. BIORESOURCE TECHNOLOGY 2012; 121:8-12. [PMID: 22858461 DOI: 10.1016/j.biortech.2012.07.010] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2012] [Revised: 07/05/2012] [Accepted: 07/07/2012] [Indexed: 05/08/2023]
Abstract
Hemicelluloses have been found to be physical barriers in the hydrolysis of cellulose, and prevent the access of enzymes to cellulose surface. In addition, soluble hemicelluloses may strongly inhibit the cellulase activity. In this work, birchwood xylan clearly inhibited the enzymatic hydrolysis of wheat straw, Avicel and nanocellulose by cellulases. Hydrolysis efficiencies of cellobiohydrolase I (CBHI, from Thermoascus aurantiacus), cellobiohydrolase II (CBHII, from Trichoderma reesei) and endoglucanase II (from T. aurantiacus) were clearly inhibited by birchwood xylan, respectively. The strongest inhibitory effect of birchwood xylan was observed on the hydrolysis of Avicel by CBHI and CBHII, as a dramatically decreased formation of the main product, cellobiose. After additions of soluble and insoluble oat spelt xylan, cleaved cellobiose units by CBHI from cellulose chain decreased from 8 to 4 and 6, respectively. The results in this work demonstrated that xylans clearly inhibited the hydrolysis efficiencies of both endoglucanase and cellobiohydrolase.
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Affiliation(s)
- Junhua Zhang
- College of Forestry, Northwest A&F University, 3 Taicheng Road, Yangling 712100, China.
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