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Angeltveit CF, Várnai A, Eijsink VGH, Horn SJ. Enhancing enzymatic saccharification yields of cellulose at high solid loadings by combining different LPMO activities. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2024; 17:39. [PMID: 38461298 PMCID: PMC10924376 DOI: 10.1186/s13068-024-02485-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Accepted: 02/24/2024] [Indexed: 03/11/2024]
Abstract
BACKGROUND The polysaccharides in lignocellulosic biomass hold potential for production of biofuels and biochemicals. However, achieving efficient conversion of this resource into fermentable sugars faces challenges, especially when operating at industrially relevant high solid loadings. While it is clear that combining classical hydrolytic enzymes and lytic polysaccharide monooxygenases (LPMOs) is necessary to achieve high saccharification yields, exactly how these enzymes synergize at high solid loadings remains unclear. RESULTS An LPMO-poor cellulase cocktail, Celluclast 1.5 L, was spiked with one or both of two fungal LPMOs from Thermothielavioides terrestris and Thermoascus aurantiacus, TtAA9E and TaAA9A, respectively, to assess their impact on cellulose saccharification efficiency at high dry matter loading, using Avicel and steam-exploded wheat straw as substrates. The results demonstrate that LPMOs can mitigate the reduction in saccharification efficiency associated with high dry matter contents. The positive effect of LPMO inclusion depends on the type of feedstock and the type of LPMO and increases with the increasing dry matter content and reaction time. Furthermore, our results show that chelating free copper, which may leak out of the active site of inactivated LPMOs during saccharification, with EDTA prevents side reactions with in situ generated H2O2 and the reductant (ascorbic acid). CONCLUSIONS This study shows that sustaining LPMO activity is vital for efficient cellulose solubilization at high substrate loadings. LPMO cleavage of cellulose at high dry matter loadings results in new chain ends and thus increased water accessibility leading to decrystallization of the substrate, all factors making the substrate more accessible to cellulase action. Additionally, this work highlights the importance of preventing LPMO inactivation and its potential detrimental impact on all enzymes in the reaction.
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Affiliation(s)
- Camilla F Angeltveit
- Faculty of Chemistry, Biotechnology, and Food Science, Norwegian University of Life Sciences (NMBU), Ås, Norway
| | - Anikó Várnai
- Faculty of Chemistry, Biotechnology, and Food Science, Norwegian University of Life Sciences (NMBU), Ås, Norway
| | - Vincent G H Eijsink
- Faculty of Chemistry, Biotechnology, and Food Science, Norwegian University of Life Sciences (NMBU), Ås, Norway
| | - Svein J Horn
- Faculty of Chemistry, Biotechnology, and Food Science, Norwegian University of Life Sciences (NMBU), Ås, Norway.
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Jiao R, Pang Y, Yang D, Li Z, Lou H. Boosting Hydrolysis of Cellulose at High Temperature by β-Glucosidase Induced Metal-Organic Framework In-Situ Co-Precipitation Encapsulation. CHEMSUSCHEM 2022; 15:e202201354. [PMID: 35934832 DOI: 10.1002/cssc.202201354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 08/01/2022] [Indexed: 06/15/2023]
Abstract
Due to the poor enzyme thermal stability, the efficient conversion of high crystallinity cellulose into glucose in aqueous phase over 50 °C is challenging. Herein, an enzyme-induced MOFs encapsulation of β-glucosidase (β-G) strategy was proposed for the first time. By using various methods, including SEM, XRD, XPS, NMR, FTIR and BET, the successful preparation of a porous channel-type flower-like enzyme complex (β-G@MOFs) was confirmed. The prepared enzyme complex (β-G@MOFs) materials showed improved thermal stability (from 50 °C to 100 °C in the aqueous phase) and excellent resistance to ionic liquids (the reaction temperature was as high as 110 °C) compared to the free enzyme (β-G). Not only the catalytic hydrolysis of cellulose by single enzyme (β-G) in ionic liquid was realized, but also the high-temperature continuous reaction performance of the enzyme was significantly improved. Benefiting from the significantly improved heat resistance, the β-G@MOFs exhibited 32.1 times and 34.2 times higher enzymatic hydrolysis rate compared to β-G for cellobiose and cellulose substrates, respectively. Besides, the catalytic activity of β-G@MOFs was retained up to 86 % after five cycles at 110 °C. This was remarkable because the fixation of the enzyme by the MOFs ensured that the folded structure of the enzyme would not expand at high temperatures, allowing the native conformation of the encapsulated protein well-maintained. Furthermore, we believe that this structural stability was caused by the confinement of flower-like porous MOFs.
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Affiliation(s)
- Rui Jiao
- Guangdong Provincial Key Lab of Green Chemical Product Technology, State Key Laboratory of Pulp and Paper Engineering, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou, 510641, P. R. China
| | - Yuxia Pang
- Guangdong Provincial Key Lab of Green Chemical Product Technology, State Key Laboratory of Pulp and Paper Engineering, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou, 510641, P. R. China
| | - Dongjie Yang
- Guangdong Provincial Key Lab of Green Chemical Product Technology, State Key Laboratory of Pulp and Paper Engineering, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou, 510641, P. R. China
| | - Zhixian Li
- Guangdong Provincial Key Lab of Green Chemical Product Technology, State Key Laboratory of Pulp and Paper Engineering, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou, 510641, P. R. China
| | - Hongming Lou
- Guangdong Provincial Key Lab of Green Chemical Product Technology, State Key Laboratory of Pulp and Paper Engineering, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou, 510641, P. R. China
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Numerical investigation of bio-inspired mixing enhancement for enzymatic hydrolysis. Chem Eng Sci 2022. [DOI: 10.1016/j.ces.2022.117950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Cellulosic Ethanol Production Using Waste Wheat Stillage after Microwave-Assisted Hydrotropic Pretreatment. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27186097. [PMID: 36144825 PMCID: PMC9506164 DOI: 10.3390/molecules27186097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Revised: 09/13/2022] [Accepted: 09/14/2022] [Indexed: 11/16/2022]
Abstract
One of the key elements influencing the efficiency of cellulosic ethanol production is the effective pretreatment of lignocellulosic biomass. The aim of the study was to evaluate the effect of microwave-assisted pretreatment of wheat stillage in the presence of sodium cumene sulphonate (NaCS) hydrotrope used for the production of second-generation bioethanol. As a result of microwave pretreatment, the composition of the wheat stillage biomass changed significantly when compared with the raw material used, before treatment. Microwave-assisted pretreatment with NaCS effectively reduced the lignin content and hemicellulose, making cellulose the dominant component of biomass, which accounted for 42.91 ± 0.10%. In post pretreatment, changes in biomass composition were also visible on FTIR spectra. The peaks of functional groups and bonds characteristic of lignins (C-O vibration in the syringyl ring, asymmetric bending in CH3, and aromatic skeleton C-C stretching) decreased. The pretreatment of the analyzed lignocellulosic raw material with NaCS resulted in the complete conversion of glucose to ethanol after 48 h of the process, with yield (in relation to the theoretical one) of above 91%. The highest observed concentration of ethanol, 23.57 ± 0.10 g/L, indicated the high effectiveness of the method used for the pretreatment of wheat stillage that did not require additional nutrient supplementation.
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Jiang X, Zhai R, Leng Y, Deng Q, Jin M. Understanding the toxicity of lignin-derived phenolics towards enzymatic saccharification of lignocellulose for rationally developing effective in-situ mitigation strategies to maximize sugar production from lignocellulosic biorefinery. BIORESOURCE TECHNOLOGY 2022; 349:126813. [PMID: 35134522 DOI: 10.1016/j.biortech.2022.126813] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Revised: 01/29/2022] [Accepted: 01/31/2022] [Indexed: 06/14/2023]
Abstract
The lignin-derived phenolics are highly inhibitory toward lignocellulose enzymatic hydrolysis, while the relationship between phenolic structure and inhibitory effect is still not fully understood. In this study, the compositions of phenolics from dilute acid pretreated wheat straw were analyzed and their impact on cellulose hydrolysis was studied. With increase of pretreatment severity, more toxic phenolics were produced from lignin degradation reactions, which were the major contributor to the increased inhibitory effect of pretreatment hydrolysate towards cellulases. Through analyzing the relationship of phenolic structure and their inhibitory effect, a useful model was developed to predict the phenolics-caused inhibition by combining the indexes of electrophilicity and hydrophobicity. Further, through understanding the interactions between phenolics and cellulases, a novel biocomponent alleviator was rationally designed to block the phenolics-cellulase interactions, the degree of improvement of enzymatic hydrolysis reached as high as 135.8%. This study provides directions for developing more effective pretreatment and detoxification methods.
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Affiliation(s)
- Xiaoxiao Jiang
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, 200 Xiaolingwei Street, Nanjing 210094, China
| | - Rui Zhai
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, 200 Xiaolingwei Street, Nanjing 210094, China
| | - Yu Leng
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, 200 Xiaolingwei Street, Nanjing 210094, China
| | - Qiufeng Deng
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, 200 Xiaolingwei Street, Nanjing 210094, China
| | - Mingjie Jin
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, 200 Xiaolingwei Street, Nanjing 210094, China.
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Mao H, Jiang H, Sang L, Li S, Chen FX, Zhao ZP. An integrated ionic liquid hybrid polymeric fixed-bed reactor with a porous sponge-like structure for biomass hydrolysis. Chem Eng Sci 2022. [DOI: 10.1016/j.ces.2022.117562] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Maniglia BC, Silveira TMG, Tapia-Blácido DR. Starch isolation from turmeric dye extraction residue and its application in active film production. Int J Biol Macromol 2022; 202:508-519. [PMID: 35007637 DOI: 10.1016/j.ijbiomac.2021.12.145] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2021] [Revised: 12/17/2021] [Accepted: 12/21/2021] [Indexed: 11/05/2022]
Abstract
In this study, we have isolated starch from turmeric dye extraction residue by steeping in acid medium (AS), steeping in water (WS), or steeping in alkaline medium (KS) and assessed the filmogenic capacity of the resulting starches. We have also characterized the chemical composition, morphology, swelling power, solubility, crystallinity, and active properties of the AS, WS, and KS starches and investigated the mechanical, functional, antioxidant, and antimicrobial properties of the corresponding films. The AS and KS starches showed lower apparent amylose content and higher purity, relative crystallinity, swelling power, and solubility than the WS starch. All the starches retained phenolic compounds and curcuminoids; their phenolic and curcuminoid contents were higher than the contents in the residue, especially in the case of the AS starch, which yielded films with the best antioxidant and antimicrobial activities. The AS and KS starches yielded films that were more resistant at break, less soluble in water, and less hydrophilic than the film obtained from the WS starch. Thus, submitting turmeric dye extraction residue to AS in ascorbic acid yielded a starch that resulted in films with good mechanical properties and better antioxidant and antimicrobial properties, to ensure safe and prolonged food shelf life.
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Affiliation(s)
- Bianca Chieregato Maniglia
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Av. Bandeirantes, 3900, CEP 14040-901 Ribeirão Preto, SP, Brazil.
| | - Thamiris Maria Garcia Silveira
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Av. Bandeirantes, 3900, CEP 14040-901 Ribeirão Preto, SP, Brazil
| | - Delia Rita Tapia-Blácido
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Av. Bandeirantes, 3900, CEP 14040-901 Ribeirão Preto, SP, Brazil.
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Migkos TM, Ioannidou G, Karapatsia A, Flevaris K, Chatzidoukas C. Enzymatic hydrolysis for the systematic production of second-generation glucose from the dual polysaccharide reserves of an anti-pollutant plant. BIORESOURCE TECHNOLOGY 2021; 340:125711. [PMID: 34385124 DOI: 10.1016/j.biortech.2021.125711] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 07/29/2021] [Accepted: 07/30/2021] [Indexed: 06/13/2023]
Abstract
In this study, the anti-pollutant macrophyte Typha domingensis is exploited for the production of highly concentrated second-generation glucose. A two-stage starch and cellulose enzymatic hydrolysis process is compared for the first time with a single-stage simultaneous starch and cellulose hydrolysis approach, with the former achieving enhanced glucose production, making it more promising for large-scale deployment. The proposed two-stage process is optimized via the Box-Behnken response surface methodology achieving glucose yield values of 74.4% and 71.7% with respect to the starch and cellulose fraction, respectively. Elevated shaking rates are shown to exert a positive effect on both starch and cellulose enzymatic hydrolysis only under high initial substrate concentrations and high initial enzyme to substrate ratios, indicating the importance of accounting for the synergies between key process variables when aiming to increase glucose production. The findings of the presented experimental framework aspire to support future scale-up studies and techno-economic assessments.
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Affiliation(s)
- Theofanis-Matthaios Migkos
- Department of Chemical Engineering, Aristotle University of Thessaloniki (AUTH), P.O. Box: 472, Thessaloniki 54124, Greece
| | - Georgia Ioannidou
- Department of Chemical Engineering, Aristotle University of Thessaloniki (AUTH), P.O. Box: 472, Thessaloniki 54124, Greece
| | - Anna Karapatsia
- Department of Chemical Engineering, Aristotle University of Thessaloniki (AUTH), P.O. Box: 472, Thessaloniki 54124, Greece; Chemical Process & Energy Resources Institute (CPERI), Centre for Research and Technology Hellas (CERTH), P.O. Box: 60361, Thermi, Thessaloniki 57001, Greece
| | - Konstantinos Flevaris
- Department of Chemical Engineering, Aristotle University of Thessaloniki (AUTH), P.O. Box: 472, Thessaloniki 54124, Greece
| | - Christos Chatzidoukas
- Department of Chemical Engineering, Aristotle University of Thessaloniki (AUTH), P.O. Box: 472, Thessaloniki 54124, Greece.
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