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Duran Garzon C, Lequart M, Charras Q, Fournet F, Bellenger L, Sellier-Richard H, Giauffret C, Vermerris W, Domon JM, Rayon C. The maize low-lignin brown midrib3 mutant shows pleiotropic effects on photosynthetic and cell wall metabolisms in response to chilling. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2022; 184:75-86. [PMID: 35636334 DOI: 10.1016/j.plaphy.2022.05.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2020] [Revised: 02/03/2022] [Accepted: 05/06/2022] [Indexed: 06/15/2023]
Abstract
Maize (Zea mays L.) is one of the major cereal crops in the world and is highly sensitive to low temperature. Here, changes in photosynthetic and cell wall metabolisms were investigated during a long chilling exposure in inbred line F2 and a low-lignin near-isogenic brown midrib3 mutant (F2bm3), which has a mutation in the caffeic acid O-methyltransferase (COMT) gene. Results revealed that the plant biomass was reduced, and this was more pronounced in F2bm3. Photosynthesis was altered in both lines with distinct changes in photosynthetic pigment content between F2bm3 and F2, indicating an alternative photoprotection mechanism between lines under chilling. Starch remobilization was observed in F2bm3 while concentrations of sucrose, fructose and starch increased in F2, suggesting a reduced sugar partitioning in F2. The cell wall was altered upon chilling, resulting in changes in the composition of glucuronorabinoxylan and a reduced cellulose level in F2. Chilling shifted lignin subunit composition in F2bm3 mutant to a higher proportion of p-hydroxyphenyl (H) units, whereas it resulted in lignin with a higher proportion of syringyl (S) residues in F2. On average, the total cell wall ferulic acid (FA) content increased in both genotypes, with an increase in ether-linked FA in F2bm3, suggesting a greater degree of cross-linking to lignin. The reinforcement of the cell wall with lignin enriched in H-units and a higher concentration in cell-wall-bound FA observed in F2bm3 as a response to chilling, could be a strategy to protect the photosystems.
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Affiliation(s)
- Catalina Duran Garzon
- UMR-INRAE 1158 Transfrontalière BioEcoAgro, BIOlogie des Plantes et Innovation (BIOPI), Université de Picardie Jules Verne, 80039, Amiens, France
| | - Michelle Lequart
- UMR-INRAE 1158 Transfrontalière BioEcoAgro, BIOlogie des Plantes et Innovation (BIOPI), Université de Picardie Jules Verne, 80039, Amiens, France
| | - Quentin Charras
- UMR 7265 Aix Marseille Université, CEA, CNRS, BIAM, Laboratoire de Génétique et Biophysique des Plantes, 13108, Saint Paul-Lez-Durance, France
| | - Françoise Fournet
- UMR-INRAE 1158 Transfrontalière BioEcoAgro, BIOlogie des Plantes et Innovation (BIOPI), Université de Picardie Jules Verne, 80039, Amiens, France
| | - Léo Bellenger
- UMR-INRAE 1158 Transfrontalière BioEcoAgro, BIOlogie des Plantes et Innovation (BIOPI), Université de Picardie Jules Verne, 80039, Amiens, France; EA2106 Biomolécules et Biotechnologies Végétales, Faculté de Pharmacie, Université de Tours, Parc de Grandmont, 37200, Tours, France
| | - Hélène Sellier-Richard
- UMR-INRAE 1158 Transfrontalière BioEcoAgro, Unité Expérimentale Grandes Cultures Innovation et Environnement, Estrées-Mons, 80203, Péronne, France
| | - Catherine Giauffret
- UMR-INRAE 1158 Transfrontalière BioEcoAgro, AgroImpact, Estrées-Mons, 80203, Péronne, France
| | - Wilfred Vermerris
- Department of Microbiology & Cell Science, UF Genetics Institute, Florida Center for Renewable Chemicals and Fuels, University of Florida, Gainesville, FL, 32610, USA
| | - Jean-Marc Domon
- UMR-INRAE 1158 Transfrontalière BioEcoAgro, BIOlogie des Plantes et Innovation (BIOPI), Université de Picardie Jules Verne, 80039, Amiens, France
| | - Catherine Rayon
- UMR-INRAE 1158 Transfrontalière BioEcoAgro, BIOlogie des Plantes et Innovation (BIOPI), Université de Picardie Jules Verne, 80039, Amiens, France.
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Leroy A, Devaux MF, Fanuel M, Chauvet H, Durand S, Alvarado C, Habrant A, Sandt C, Rogniaux H, Paës G, Guillon F. Real-time imaging of enzymatic degradation of pretreated maize internodes reveals different cell types have different profiles. BIORESOURCE TECHNOLOGY 2022; 353:127140. [PMID: 35405211 DOI: 10.1016/j.biortech.2022.127140] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Revised: 04/05/2022] [Accepted: 04/06/2022] [Indexed: 06/14/2023]
Abstract
This work presents a dynamic view of the enzymatic degradation of maize cell walls, and sheds new light on the recalcitrance of hot water pretreated maize stem internodes. Infra-red microspectrometry, mass spectrometry, fluorescence recovery after photobleaching and fluorescence imaging were combined to investigate enzymatic hydrolysis at the cell scale. Depending on their polymer composition and organisation, cell types exhibits different extent and rate of enzymatic degradation. Enzymes act sequentially from the cell walls rich in accessible cellulose to the most recalcitrant cells. This phenomenon can be linked to the heterogeneous distribution of enzymes in the liquid medium and the adsorption/desorption mechanisms that differ with the type of cell.
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Affiliation(s)
- Amandine Leroy
- INRAE, UR 1268 BIA, 44316 Nantes, France; Université de Reims Champagne Ardenne, INRAE, FARE, UMR A614, 51100 Reims, France
| | | | - Mathieu Fanuel
- INRAE, UR 1268 BIA, 44316 Nantes, France; INRAE, BIBS Facility, 44316 Nantes, France
| | - Hugo Chauvet
- DISCO Beamline, SOLEIL Synchrotron, BP48, l'Orme des Merisiers, 91192 Gif-sur-Yvette CEDEX, France
| | | | | | - Anouck Habrant
- Université de Reims Champagne Ardenne, INRAE, FARE, UMR A614, 51100 Reims, France
| | - Christophe Sandt
- SMIS Beamline, SOLEIL Synchrotron, BP48, l'Orme des Merisiers, 91192 Gif-sur-Yvette CEDEX, France
| | - Hélène Rogniaux
- INRAE, UR 1268 BIA, 44316 Nantes, France; INRAE, BIBS Facility, 44316 Nantes, France
| | - Gabriel Paës
- Université de Reims Champagne Ardenne, INRAE, FARE, UMR A614, 51100 Reims, France
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Dos Santos ACF, Overton JC, Szeto R, Patel MH, Gutierrez DMR, Eby C, Martínez Moreno AM, Erk KA, Aston JE, Thompson DN, Dooley JH, Sharma P, Mosier NS, Ximenes E, Ladisch MR. New strategy for liquefying corn stover pellets. BIORESOURCE TECHNOLOGY 2021; 341:125773. [PMID: 34419879 DOI: 10.1016/j.biortech.2021.125773] [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: 06/23/2021] [Revised: 08/10/2021] [Accepted: 08/11/2021] [Indexed: 06/13/2023]
Abstract
The movement of solid material into and between unit operations within a biorefinery is a bottleneck in reaching design capacity, with formation of biomass slurries needed to introduce feedstock. Corn stover slurries have been achieved from dilute acid, pretreated materials resulting in slurry concentrations of up to about 150 g/L, above which flowability is compromised. We report a new strategy to liquefy corn stover at higher solids concentration (300 g/L) by initially cooking it with the enzyme mimetic maleic acid at 40 mM and 150 °C. This is followed by 6 h of enzymatic modification at 1 FPU (2.2 mg protein)/g solids, resulting in a yield stress of 171 Pa after 6 h and 58 Pa in 48 h compared to 6806 Pa for untreated stover. Mimetic treatment of corn stover pellets minimizes the inhibitory effect of xylo-oligomers on hydrolytic enzymes. This strategy allows for the delivery of solid lignocellulosic slurry into a pretreatment reactor by pumping, improving operability of a biorefinery.
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Affiliation(s)
- Antonio C Freitas Dos Santos
- Laboratory of Renewable Resources Engineering (LORRE), Purdue University, West Lafayette, IN 47907 United States; Department of Agricultural and Biological Engineering, Purdue University, West Lafayette, IN 47907 United States
| | - Jonathan C Overton
- Laboratory of Renewable Resources Engineering (LORRE), Purdue University, West Lafayette, IN 47907 United States; Department of Agricultural and Biological Engineering, Purdue University, West Lafayette, IN 47907 United States
| | - Ryan Szeto
- School of Materials Engineering, Purdue University, West Lafayette, IN 47907 United States
| | - Maulik H Patel
- Laboratory of Renewable Resources Engineering (LORRE), Purdue University, West Lafayette, IN 47907 United States; Department of Agricultural and Biological Engineering, Purdue University, West Lafayette, IN 47907 United States
| | - Diana M R Gutierrez
- Laboratory of Renewable Resources Engineering (LORRE), Purdue University, West Lafayette, IN 47907 United States; Department of Agricultural and Biological Engineering, Purdue University, West Lafayette, IN 47907 United States
| | - Clark Eby
- Laboratory of Renewable Resources Engineering (LORRE), Purdue University, West Lafayette, IN 47907 United States; Department of Agricultural and Biological Engineering, Purdue University, West Lafayette, IN 47907 United States
| | - Ana M Martínez Moreno
- Laboratory of Renewable Resources Engineering (LORRE), Purdue University, West Lafayette, IN 47907 United States; Departmento de Ingeniería Química y Ambiental, Universidad Nacional de Colombia, Bogotá, Colombia
| | - Kendra A Erk
- School of Materials Engineering, Purdue University, West Lafayette, IN 47907 United States
| | - John E Aston
- Chemical Systems, Idaho National Laboratory, Idaho Falls, Idaho 83415 United States
| | - David N Thompson
- Biomass Characterization, Idaho National Laboratory, Idaho Falls, Idaho 83415 United States
| | - James H Dooley
- Forest Concepts LLC., Auburn, Washington 98001 United States
| | - Pankaj Sharma
- Discovery Park, Purdue University, West Lafayette, IN 47907 United States
| | - Nathan S Mosier
- Laboratory of Renewable Resources Engineering (LORRE), Purdue University, West Lafayette, IN 47907 United States; Department of Agricultural and Biological Engineering, Purdue University, West Lafayette, IN 47907 United States
| | - Eduardo Ximenes
- Laboratory of Renewable Resources Engineering (LORRE), Purdue University, West Lafayette, IN 47907 United States; Department of Agricultural and Biological Engineering, Purdue University, West Lafayette, IN 47907 United States
| | - Michael R Ladisch
- Laboratory of Renewable Resources Engineering (LORRE), Purdue University, West Lafayette, IN 47907 United States; Department of Agricultural and Biological Engineering, Purdue University, West Lafayette, IN 47907 United States; Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN 47907 United States.
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Leroy A, Falourd X, Foucat L, Méchin V, Guillon F, Paës G. Evaluating polymer interplay after hot water pretreatment to investigate maize stem internode recalcitrance. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:164. [PMID: 34332625 PMCID: PMC8325808 DOI: 10.1186/s13068-021-02015-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Accepted: 07/21/2021] [Indexed: 05/12/2023]
Abstract
BACKGROUND Biomass recalcitrance is governed by various molecular and structural factors but the interplay between these multiscale factors remains unclear. In this study, hot water pretreatment (HWP) was applied to maize stem internodes to highlight the impact of the ultrastructure of the polymers and their interactions on the accessibility and recalcitrance of the lignocellulosic biomass. The impact of HWP was analysed at different scales, from the polymer ultrastructure or water mobility to the cell wall organisation by combining complementary compositional, spectral and NMR analyses. RESULTS HWP increased the kinetics and yield of saccharification. Chemical characterisation showed that HWP altered cell wall composition with a loss of hemicelluloses (up to 45% in the 40-min HWP) and of ferulic acid cross-linking associated with lignin enrichment. The lignin structure was also altered (up to 35% reduction in β-O-4 bonds), associated with slight depolymerisation/repolymerisation depending on the length of treatment. The increase in [Formula: see text], [Formula: see text] and specific surface area (SSA) showed that the cellulose environment was looser after pretreatment. These changes were linked to the increased accessibility of more constrained water to the cellulose in the 5-15 nm pore size range. CONCLUSION The loss of hemicelluloses and changes in polymer structural features caused by HWP led to reorganisation of the lignocellulose matrix. These modifications increased the SSA and redistributed the water thereby increasing the accessibility of cellulases and enhancing hydrolysis. Interestingly, lignin content did not have a negative impact on enzymatic hydrolysis but a higher lignin condensed state appeared to promote saccharification. The environment and organisation of lignin is thus more important than its concentration in explaining cellulose accessibility. Elucidating the interactions between polymers is the key to understanding LB recalcitrance and to identifying the best severity conditions to optimise HWP in sustainable biorefineries.
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Affiliation(s)
- Amandine Leroy
- INRAE, UR 1268 BIA, 44316, Nantes, France
- Université de Reims Champagne Ardenne, INRAE, FARE, UMR A614, 51100, Reims, France
| | - Xavier Falourd
- INRAE, UR 1268 BIA, 44316, Nantes, France
- INRAE, BIBS Facility, 44316, Nantes, France
| | - Loïc Foucat
- INRAE, UR 1268 BIA, 44316, Nantes, France
- INRAE, BIBS Facility, 44316, Nantes, France
| | - Valérie Méchin
- INRAE, Institut Jean-Pierre Bourgin, 78026, Versailles, France
| | | | - Gabriel Paës
- Université de Reims Champagne Ardenne, INRAE, FARE, UMR A614, 51100, Reims, France.
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Alokika, Anu, Kumar A, Kumar V, Singh B. Cellulosic and hemicellulosic fractions of sugarcane bagasse: Potential, challenges and future perspective. Int J Biol Macromol 2020; 169:564-582. [PMID: 33385447 DOI: 10.1016/j.ijbiomac.2020.12.175] [Citation(s) in RCA: 69] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 11/29/2020] [Accepted: 12/23/2020] [Indexed: 12/01/2022]
Abstract
Sugarcane bagasse is a rich source of cellulose (32-45%), hemicellulose (20-32%) and lignin (17-32%), 1.0-9.0% ash and some extractives. Huge amount of the generation of sugarcane bagasse has been a great challenge to industries and environment at global level for many years. Though cellulosic and hemicellulosic fractions in bagasse makes it a potential raw substrate for the production of value-added products at large scale, the presence of lignin hampers its saccharification which further leads to low yields of the value-added products. Therefore, an appropriate pretreatment strategy is of utmost importance that effectively solubilizes the lignin that exposes cellulose and hemicellulose for enzymatic action. Pretreatment also reduces the biomass recalcitrance i.e., cellulose crystallinity, structural complexity of cell wall and lignification for its effective utilization in biorefinery. Sugarcane bagasse served as nutrient medium for the cultivation of diverse microorganisms for the production of industrially important metabolites including enzymes, reducing sugars, prebiotic, organic acids and biofuels. Sugarcane bagasse has been utilized in the generation of electricity, syngas and as biosorbant in the bioremediation of heavy metals. Furthermore, the ash generated from bagasse is an excellent source for the synthesis of high strength and light weight bricks and tiles. Present review describes the utility of sugarcane bagasse as sustainable and renewable lignocellulosic substrate for the production of industrially important multifarious value-added products.
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Affiliation(s)
- Alokika
- Laboratory of Bioprocess Technology, Department of Microbiology, Maharshi Dayanand University, Rohtak 124001, Haryana, India
| | - Anu
- Laboratory of Bioprocess Technology, Department of Microbiology, Maharshi Dayanand University, Rohtak 124001, Haryana, India
| | - Anil Kumar
- Department of Botany, Pt. N.R.S. Govt. College, Rohtak 124001, Haryana, India
| | - Vinod Kumar
- Department of Chemistry, Central University of Haryana, Jant-Pali, Mahendergarh 123031, Haryana, India
| | - Bijender Singh
- Laboratory of Bioprocess Technology, Department of Microbiology, Maharshi Dayanand University, Rohtak 124001, Haryana, India; Department of Biotechnology, Central University of Haryana, Jant-Pali, Mahendergarh 123031, Haryana, India.
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Nguyen QA, Smith WA, Wahlen BD, Wendt LM. Total and Sustainable Utilization of Biomass Resources: A Perspective. Front Bioeng Biotechnol 2020; 8:546. [PMID: 32582670 PMCID: PMC7290042 DOI: 10.3389/fbioe.2020.00546] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Accepted: 05/06/2020] [Indexed: 11/13/2022] Open
Abstract
Feedstock cost is a major variable cost component in conversion to biofuels and chemicals. Consistent feedstock quality is critically important to achieve high product yield and maximum onstream time. Traditionally, raw biomass materials are delivered directly to the biorefineries where they are preprocessed to feedstock prior to being converted to products. Since many types of biomass materials-including agricultural residues, energy crops, and logging residues-are harvested according to growth cycles and optimal harvesting time, just-in-time steady supply of raw biomass to the biorefineries is not possible. Instead, biomass materials are stored, then delivered to the biorefineries as needed. Experience to date indicates that this approach has caused many issues related to logistics, biomass losses due to microbial degradation and fire, and inconsistent feedstock quality due to variability in the properties of as-delivered biomass. These factors have led to high feedstock cost, low throughput, and low product yield for the biorefineries. Idaho National Laboratory has developed a new strategy to address the problems encountered in the traditional approach in biomass feedstock supply, storage, and preprocessing mentioned above. The key components of this strategy are (1) preservation and preconditioning of biomass during storage, (2) utilization of all the biomass, including minor components that are normally considered wastes or contaminants, and (3) maximization of the value of each component. This new approach can be accomplished using feedstock preprocessing depots located near the biomass-production sources.
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Vasconcellos VM, Farinas CS, Ximenes E, Slininger P, Ladisch M. Adaptive laboratory evolution of nanocellulose‐producing bacterium. Biotechnol Bioeng 2019; 116:1923-1933. [DOI: 10.1002/bit.26997] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 04/19/2019] [Accepted: 04/25/2019] [Indexed: 12/22/2022]
Affiliation(s)
- Vanessa M. Vasconcellos
- Graduate Program of Chemical Engineering Federal University of São Carlos São Carlos São Paulo Brazil
- Embrapa Instrumentation São Carlos São Paulo Brazil
| | - Cristiane S. Farinas
- Graduate Program of Chemical Engineering Federal University of São Carlos São Carlos São Paulo Brazil
- Embrapa Instrumentation São Carlos São Paulo Brazil
| | - Eduardo Ximenes
- Laboratory of Renewable Resources Engineering Weldon School of Biomedical Engineering, Agricultural and Biological Engineering, Purdue University West Lafayette Indiana
| | - Patricia Slininger
- Bioenergy Research Unit Anchor National Center for Agricultural Utilization Research USDA Peoria Illinois
| | - Michael Ladisch
- Laboratory of Renewable Resources Engineering Weldon School of Biomedical Engineering, Agricultural and Biological Engineering, Purdue University West Lafayette Indiana
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Dos Santos AC, Ximenes E, Kim Y, Ladisch MR. Lignin-Enzyme Interactions in the Hydrolysis of Lignocellulosic Biomass. Trends Biotechnol 2018; 37:518-531. [PMID: 30477739 DOI: 10.1016/j.tibtech.2018.10.010] [Citation(s) in RCA: 93] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Revised: 10/22/2018] [Accepted: 10/25/2018] [Indexed: 12/20/2022]
Abstract
Lignin is central to overcoming recalcitrance in the enzyme hydrolysis of lignocellulose. While the term implies a physical barrier in the cell wall structure, there are also important biochemical components that direct interactions between lignin and the hydrolytic enzymes that attack cellulose in plant cell walls. Progress toward a deeper understanding of the lignin synthesis pathway - and the consistency between a range of observations over the past 40 years in the very extensive literature on cellulose hydrolysis - is resulting in advances in reducing a major impediment to cellulose conversion: the cost of enzymes. This review addresses lignin and its role in the hydrolysis of hardwood and other lignocellulosic residues.
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Affiliation(s)
- Antonio Carlos Dos Santos
- Laboratory of Renewable Resources Engineering, Purdue University, West Lafayette, IN 47907, USA; Department of Agricultural and Biological Engineering, Purdue University, West Lafayette, IN 47907, USA
| | - Eduardo Ximenes
- Laboratory of Renewable Resources Engineering, Purdue University, West Lafayette, IN 47907, USA; Department of Agricultural and Biological Engineering, Purdue University, West Lafayette, IN 47907, USA
| | - Youngmi Kim
- Department of Agricultural Engineering Technology, University of Wisconsin, River Falls, WI 54022, USA
| | - Michael R Ladisch
- Laboratory of Renewable Resources Engineering, Purdue University, West Lafayette, IN 47907, USA; Department of Agricultural and Biological Engineering, Purdue University, West Lafayette, IN 47907, USA; Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN 47907, USA; www.purdue.edu/LORRE.
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Isaac A, de Paula J, Viana CM, Henriques AB, Malachias A, Montoro LA. From nano- to micrometer scale: the role of microwave-assisted acid and alkali pretreatments in the sugarcane biomass structure. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:73. [PMID: 29588658 PMCID: PMC5863382 DOI: 10.1186/s13068-018-1071-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Accepted: 03/08/2018] [Indexed: 05/24/2023]
Abstract
BACKGROUND To date, great strides have been made in elucidating the role of thermochemical pretreatments in the chemical and structural features of plant cell walls; however, there is no clear picture of the plant recalcitrance and its relationship to deconstruction. Previous studies precluded full answers due to the challenge of multiscale features of plant cell wall organization. Complementing the previous efforts, we undertook a systematic, multiscale, and integrated approach to track the effect of microwave-assisted H2SO4 and NaOH treatments on the hierarchical structure of plants, i.e., from a nano- to micrometer scale. We focused on the investigation of the highly recalcitrant sclerenchyma cell walls from sugarcane bagasse. RESULTS Through atomic force microscopy and X-ray diffraction analyses, remarkable details of the assembly of cellulose microfibrils not previously seen were revealed. Following the H2SO4 treatment, we observed that cellulose microfibrils were almost double the width of the alkali pretreated sample at the temperature of 160 °C. Such enlargement led to a greater contact between cellulose chains, with a subsequent molecule alignment, as indicated by the X-ray diffraction (XRD) results with the conspicuous expansion of the average crystallite size. The delignification process had little effect on the local nanometer-sized arrangement of cellulose molecules. However, the rigidity and parallel alignment of cellulose microfibrils were partially degraded. The XRD analysis also agrees with these findings as evidenced by large momentum transfer vectors (q > 20 nm-1), interpreted as indicators of the long-range order of cell wall components, which were similar for all the studied samples except with application of the NaOH treatment at 160 °C. These changes were followed by the eventual swelling of the fiber cell walls. CONCLUSIONS Based on an integrated approach, we presented multidimensional architectural models of cell wall deconstruction resulting from microwave-assisted pretreatments. We provided direct evidence supporting the idea that hemicellulose is the main barrier for the swelling of cellulose microfibrils, whereas lignin adds rigidity to cell walls. Our findings shed light on the design of more efficient strategies, not only for the conversion of biomass to fuels but also for the production of nanocellulose, which has great potential for several applications such as composites, rheology modifiers, and pharmaceuticals.
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Affiliation(s)
- Augusta Isaac
- Department of Metallurgical and Materials Engineering, Universidade Federal de Minas Gerais, Belo Horizonte, 31270-901 Brazil
| | - Jéssica de Paula
- Microscopy Center, Universidade Federal de Minas Gerais, Belo Horizonte, 31270-901 Brazil
| | - Carlos Martins Viana
- Department of Metallurgical and Materials Engineering, Universidade Federal de Minas Gerais, Belo Horizonte, 31270-901 Brazil
| | - Andréia Bicalho Henriques
- Mining Engineering Department, Universidade Federal de Minas Gerais, Belo Horizonte, 31270-901 Brazil
| | - Angelo Malachias
- Department of Physics, Universidade Federal de Minas Gerais, Belo Horizonte, 31270-901 Brazil
| | - Luciano A. Montoro
- Department of Chemistry, Universidade Federal de Minas Gerais, Belo Horizonte, 31270-901 Brazil
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10
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Zanchetta A, Dos Santos ACF, Ximenes E, da Costa Carreira Nunes C, Boscolo M, Gomes E, Ladisch MR. Temperature dependent cellulase adsorption on lignin from sugarcane bagasse. BIORESOURCE TECHNOLOGY 2018; 252:143-149. [PMID: 29316500 DOI: 10.1016/j.biortech.2017.12.061] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Revised: 12/18/2017] [Accepted: 12/19/2017] [Indexed: 05/08/2023]
Abstract
Extents of adsorption of cellulolytic enzymes on lignin, derived from sugarcane bagasse, were an inverse function of incubation temperature and varied with type of lignin extraction. At 45 °C, lignin derived from acid hydrolyzed liquid hot water pretreated bagasse completely adsorbed cellulolytic enzymes from Trichoderma reesei within 90 min. Lignin derived from enzyme hydrolyzed liquid hot water pretreated bagasse adsorbed only 60% of T. reesei endoglucanase, exoglucanase and β-glucosidase activities. β-Glucosidase from Aspergillus niger was not adsorbed. At 30 °C, adsorption of all of the enzymes was minimal and enzyme hydrolysis at 30 °C approached that at 45 °C after 168 h. Hence, temperature provided an approach to decrease loss of enzyme activity by reducing enzyme adsorption on lignin. This helps to explain why simultaneous saccharification and fermentation (SSF) and consolidated bioprocessing (CBP), both carried out at 30-32 °C, could offer viable options for mitigating lignin-derived inhibition effects.
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Affiliation(s)
- Ariane Zanchetta
- Sao Paulo State University-Unesp, IBILCE, São José do Rio Preto, São Paulo, Brazil; Laboratory of Renewable Resources Engineering, Purdue University, West Lafayette, IN, USA
| | - Antonio Carlos Freitas Dos Santos
- Laboratory of Renewable Resources Engineering, Purdue University, West Lafayette, IN, USA; Department of Agricultural and Biological Engineering, Purdue University, West Lafayette, IN, USA
| | - Eduardo Ximenes
- Laboratory of Renewable Resources Engineering, Purdue University, West Lafayette, IN, USA; Department of Agricultural and Biological Engineering, Purdue University, West Lafayette, IN, USA
| | | | - Maurício Boscolo
- Sao Paulo State University-Unesp, IBILCE, São José do Rio Preto, São Paulo, Brazil
| | - Eleni Gomes
- Sao Paulo State University-Unesp, IBILCE, São José do Rio Preto, São Paulo, Brazil
| | - Michael R Ladisch
- Laboratory of Renewable Resources Engineering, Purdue University, West Lafayette, IN, USA; Department of Agricultural and Biological Engineering, Purdue University, West Lafayette, IN, USA.
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11
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Yao K, Wu Q, An R, Meng W, Ding M, Li B, Yuan Y. Hydrothermal pretreatment for deconstruction of plant cell wall: Part I. Effect on lignin-carbohydrate complex. AIChE J 2018. [DOI: 10.1002/aic.16114] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Kun Yao
- School of Chemical Engineering and Technology; Tianjin University; Tianjin 300072 China
- Key Laboratory of Systems Bioengineering, Ministry of Education; Tianjin 300072 China
- Collaborative Innovation Center of Chemical Science and Engineering; Tianjin China
| | - Qinfeng Wu
- School of Chemical Engineering and Technology; Tianjin University; Tianjin 300072 China
- Key Laboratory of Systems Bioengineering, Ministry of Education; Tianjin 300072 China
- Collaborative Innovation Center of Chemical Science and Engineering; Tianjin China
| | - Ran An
- School of Chemical Engineering and Technology; Tianjin University; Tianjin 300072 China
- Key Laboratory of Systems Bioengineering, Ministry of Education; Tianjin 300072 China
- Collaborative Innovation Center of Chemical Science and Engineering; Tianjin China
| | - Wei Meng
- School of Chemical Engineering and Technology; Tianjin University; Tianjin 300072 China
- Key Laboratory of Systems Bioengineering, Ministry of Education; Tianjin 300072 China
- Collaborative Innovation Center of Chemical Science and Engineering; Tianjin China
| | - Mingzhu Ding
- School of Chemical Engineering and Technology; Tianjin University; Tianjin 300072 China
- Key Laboratory of Systems Bioengineering, Ministry of Education; Tianjin 300072 China
- Collaborative Innovation Center of Chemical Science and Engineering; Tianjin China
| | - Bingzhi Li
- School of Chemical Engineering and Technology; Tianjin University; Tianjin 300072 China
- Key Laboratory of Systems Bioengineering, Ministry of Education; Tianjin 300072 China
- Collaborative Innovation Center of Chemical Science and Engineering; Tianjin China
| | - Yingjin Yuan
- School of Chemical Engineering and Technology; Tianjin University; Tianjin 300072 China
- Key Laboratory of Systems Bioengineering, Ministry of Education; Tianjin 300072 China
- Collaborative Innovation Center of Chemical Science and Engineering; Tianjin China
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12
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Yang G, Sun Y, Li L, Lv P, Kong X, Huang D. Hydrolysis dynamics for batch anaerobic digestion of elephant grass. RSC Adv 2018; 8:22670-22675. [PMID: 35539704 PMCID: PMC9081458 DOI: 10.1039/c8ra01115j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Accepted: 06/11/2018] [Indexed: 11/21/2022] Open
Abstract
Elephant grass might be a potential source of fine chemical precursors and bioenergy.
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Affiliation(s)
- Gaixiu Yang
- Guangzhou Institute of Energy Conversion
- Key Laboratory of Renewable Energy
- Guangdong Key Laboratory of New and Renewable Energy Research and Development
- Chinese Academy of Sciences
- Guangzhou 510640
| | - Yongming Sun
- Guangzhou Institute of Energy Conversion
- Key Laboratory of Renewable Energy
- Guangdong Key Laboratory of New and Renewable Energy Research and Development
- Chinese Academy of Sciences
- Guangzhou 510640
| | - Lianhua Li
- Guangzhou Institute of Energy Conversion
- Key Laboratory of Renewable Energy
- Guangdong Key Laboratory of New and Renewable Energy Research and Development
- Chinese Academy of Sciences
- Guangzhou 510640
| | - Pengmei Lv
- Guangzhou Institute of Energy Conversion
- Key Laboratory of Renewable Energy
- Guangdong Key Laboratory of New and Renewable Energy Research and Development
- Chinese Academy of Sciences
- Guangzhou 510640
| | - Xiaoying Kong
- Guangzhou Institute of Energy Conversion
- Key Laboratory of Renewable Energy
- Guangdong Key Laboratory of New and Renewable Energy Research and Development
- Chinese Academy of Sciences
- Guangzhou 510640
| | - Dalong Huang
- Guangzhou Institute of Energy Conversion
- Key Laboratory of Renewable Energy
- Guangdong Key Laboratory of New and Renewable Energy Research and Development
- Chinese Academy of Sciences
- Guangzhou 510640
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13
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Wood IP, Garcia-Gutierrez E, Wellner N, Waldron KW. Feedstock selection for polymer and chemical production: feedstock-specific recalcitrance. Faraday Discuss 2017; 202:391-402. [PMID: 28682402 DOI: 10.1039/c7fd00044h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Plant cell wall materials derived from a range of waste biomass sources have great potential as a source of sustainable alternatives to petrochemicals. Perhaps the most straightforward way of realising this potential would be to hydrolyse the most efficiently fermentable polymers into their constituent sugars and use yeast to ferment these into useful chemicals. However, it also makes sense to pre-extract components which have a greater value in polymeric form. This is particularly true for non-cellulosic polymers, which are rich in poorly-fermentable pentose sugars. Liquid hot water (LHW) pretreatment can be used to extract non-cellulosic carbohydrates in a cost-effective manner, leaving a cellulose-rich substrate which is easier to hydrolyse using commercial cellulases. However, inherent differences in the plant cell wall structure and composition mean that some biomass sources may be more suitable for exploitation than others. Here, we examine eight different feedstocks (two each from hardwood, softwood, cereal straws and dicotyledonous crops), expose them to 26 different LHW pretreatment conditions and hydrolyse the entire pretreated slurry with a commercial cellulase. This enables side-by-side comparisons, in terms of saccharification yield, of the feedstocks. The results clearly demonstrate considerable differences in suitability between the feedstocks, in relation to the quantity of products released and the processes needed to obtain them.
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Affiliation(s)
- Ian P Wood
- Quadram Institute Bioscience, Norwich Research Park, Colney, Norwich NR47UA, UK.
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14
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Li X, Zheng Y. Lignin-enzyme interaction: Mechanism, mitigation approach, modeling, and research prospects. Biotechnol Adv 2017; 35:466-489. [DOI: 10.1016/j.biotechadv.2017.03.010] [Citation(s) in RCA: 115] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Revised: 02/19/2017] [Accepted: 03/23/2017] [Indexed: 01/23/2023]
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15
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Bondancia TJ, Mattoso LHC, Marconcini JM, Farinas CS. A new approach to obtain cellulose nanocrystals and ethanol from eucalyptus cellulose pulp via the biochemical pathway. Biotechnol Prog 2017; 33:1085-1095. [DOI: 10.1002/btpr.2486] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Revised: 03/27/2017] [Indexed: 11/09/2022]
Affiliation(s)
- Thalita J. Bondancia
- Graduate Program of Chemical Engineering; Federal University of São Carlos, São Carlos; SP 13565-905 Brazil
- National Nanotechnology Laboratory for Agribusiness (LNNA); Embrapa Instrumentação; Rua XV de Novembro, 1452 São Carlos SP 13560-970 Brazil
| | - Luiz Henrique C. Mattoso
- National Nanotechnology Laboratory for Agribusiness (LNNA); Embrapa Instrumentação; Rua XV de Novembro, 1452 São Carlos SP 13560-970 Brazil
| | - José M. Marconcini
- National Nanotechnology Laboratory for Agribusiness (LNNA); Embrapa Instrumentação; Rua XV de Novembro, 1452 São Carlos SP 13560-970 Brazil
| | - Cristiane S. Farinas
- Graduate Program of Chemical Engineering; Federal University of São Carlos, São Carlos; SP 13565-905 Brazil
- National Nanotechnology Laboratory for Agribusiness (LNNA); Embrapa Instrumentação; Rua XV de Novembro, 1452 São Carlos SP 13560-970 Brazil
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16
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Crowe JD, Feringa N, Pattathil S, Merritt B, Foster C, Dines D, Ong RG, Hodge DB. Identification of developmental stage and anatomical fraction contributions to cell wall recalcitrance in switchgrass. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:184. [PMID: 28725264 PMCID: PMC5512841 DOI: 10.1186/s13068-017-0870-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Accepted: 07/06/2017] [Indexed: 05/08/2023]
Abstract
BACKGROUND Heterogeneity within herbaceous biomass can present important challenges for processing feedstocks to cellulosic biofuels. Alterations to cell wall composition and organization during plant growth represent major contributions to heterogeneity within a single species or cultivar. To address this challenge, the focus of this study was to characterize the relationship between composition and properties of the plant cell wall and cell wall response to deconstruction by NaOH pretreatment and enzymatic hydrolysis for anatomical fractions (stem internodes, leaf sheaths, and leaf blades) within switchgrass at various tissue maturities as assessed by differing internode. RESULTS Substantial differences in both cell wall composition and response to deconstruction were observed as a function of anatomical fraction and tissue maturity. Notably, lignin content increased with tissue maturity concurrently with decreasing ferulate content across all three anatomical fractions. Stem internodes exhibited the highest lignin content as well as the lowest hydrolysis yields, which were inversely correlated to lignin content. Confocal microscopy was used to demonstrate that removal of cell wall aromatics (i.e., lignins and hydroxycinnamates) by NaOH pretreatment was non-uniform across diverse cell types. Non-cellulosic polysaccharides were linked to differences in cell wall response to deconstruction in lower lignin fractions. Specifically, leaf sheath and leaf blade were found to have higher contents of substituted glucuronoarabinoxylans and pectic polysaccharides. Glycome profiling demonstrated that xylan and pectic polysaccharide extractability varied with stem internode maturity, with more mature internodes requiring harsher chemical extractions to remove comparable glycan abundances relative to less mature internodes. While enzymatic hydrolysis was performed on extractives-free biomass, extractible sugars (i.e., starch and sucrose) comprised a significant portion of total dry weight particularly in stem internodes, and may provide an opportunity for recovery during processing. CONCLUSIONS Cell wall structural differences within a single plant can play a significant role in feedstock properties and have the potential to be exploited for improving biomass processability during a biorefining process. The results from this work demonstrate that cell wall lignin content, while generally exhibiting a negative correlation with enzymatic hydrolysis yields, is not the sole contributor to cell wall recalcitrance across diverse anatomical fractions within switchgrass.
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Affiliation(s)
- Jacob D. Crowe
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI USA
| | - Nicholas Feringa
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI USA
| | - Sivakumar Pattathil
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA USA
- Bioenergy Science Center, Oak Ridge National Laboratory, Oak Ridge, TN USA
| | - Brian Merritt
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA USA
| | - Cliff Foster
- DOE-Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI USA
| | - Dayna Dines
- DOE-Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI USA
| | - Rebecca G. Ong
- Department of Chemical Engineering, Michigan Technological University, Houghton, MI USA
| | - David B. Hodge
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI USA
- DOE-Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI USA
- Department of Biosystems & Agricultural Engineering, Michigan State University, East Lansing, MI USA
- Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, Luleå, Sweden
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17
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Yang X, Ma X, Li H, Chen J, Fang S. Effects of hot-washing process on structure and enzymatic hydrolysis of treated steam explosion corn stover. BIORESOUR BIOPROCESS 2016. [DOI: 10.1186/s40643-016-0115-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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18
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Costa THF, Vega-Sánchez ME, Milagres AMF, Scheller HV, Ferraz A. Tissue-specific distribution of hemicelluloses in six different sugarcane hybrids as related to cell wall recalcitrance. BIOTECHNOLOGY FOR BIOFUELS 2016; 9:99. [PMID: 27148403 PMCID: PMC4855430 DOI: 10.1186/s13068-016-0513-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Accepted: 04/20/2016] [Indexed: 05/05/2023]
Abstract
BACKGROUND Grasses are lignocellulosic materials useful to supply the billion-tons annual requirement for renewable resources that aim to produce transportation fuels and a variety of chemicals. However, the polysaccharides contained in grass cell walls are built in a recalcitrant composite. Deconstruction of these cell walls is still a challenge for the energy-efficient and economically viable transformation of lignocellulosic materials. The varied tissue-specific distribution of cell wall components adds complexity to the origins of cell wall recalcitrance in grasses. This complexity usually led to empirically developed pretreatment processes to overcome recalcitrance. A further complication is that efficient pretreatment procedures generally treat the less recalcitrant tissues more than necessary, which results in the generation of undesirable biomass degradation products. RESULTS Six different sugarcane hybrids were used as model grasses to evaluate the tissue-specific distribution of hemicelluloses and the role of these components in cell wall recalcitrance. Acetylated glucuronoarabinoxylan (GAX) occurs in all tissues. Mixed-linkage glucan (MLG) was relevant in the innermost regions of the sugarcane internodes (up to 15.4 % w/w), especially in the low-lignin content hybrids. Immunofluorescence microscopy showed that xylans predominated in vascular bundles, whereas MLG occurred mostly in the parenchyma cell walls from the pith region of the hybrids with low-lignin content. Evaluation of the digestibility of sugarcane polysaccharides by commercial enzymes indicated that the cell wall recalcitrance varied considerably along the internode regions and in the sugarcane hybrids. Pith regions of the hybrids with high MLG and low-lignin contents reached up to 85 % cellulose conversion after 72 h of hydrolysis, without any pretreatment. CONCLUSIONS The collective characteristics of the internode regions were related to the varied recalcitrance found in the samples. Components such as lignin and GAX were critical for the increased recalcitrance, but low cellulose crystallinity index, high MLG contents, and highly substituted GAX contributed to the generation of a less recalcitrant material.
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Affiliation(s)
- Thales H. F. Costa
- />Departamento de Biotecnologia, Escola de Engenharia de Lorena, Universidade de São Paulo, Lorena, SP 12602-810 Brazil
| | - Miguel E. Vega-Sánchez
- />The Joint BioEnergy Institute, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd., Berkeley, CA 94720 USA
- />Monsanto Company, 800N. Lindbergh Blvd., Creve Coeur (St. Louis), MO 63141 USA
| | - Adriane M. F. Milagres
- />Departamento de Biotecnologia, Escola de Engenharia de Lorena, Universidade de São Paulo, Lorena, SP 12602-810 Brazil
| | - Henrik V. Scheller
- />The Joint BioEnergy Institute, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd., Berkeley, CA 94720 USA
| | - André Ferraz
- />Departamento de Biotecnologia, Escola de Engenharia de Lorena, Universidade de São Paulo, Lorena, SP 12602-810 Brazil
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19
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Yu Q, Zhuang X, Yuan Z, Kong X, Qi W, Wang W, Wang Q, Tan X. Influence of lignin level on release of hemicellulose-derived sugars in liquid hot water. Int J Biol Macromol 2015; 82:967-72. [PMID: 26484600 DOI: 10.1016/j.ijbiomac.2015.10.045] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Revised: 10/12/2015] [Accepted: 10/14/2015] [Indexed: 11/26/2022]
Abstract
Lignin layers surrounding hemicelluloses and cellulose in the plant cell walls protect them from deconstruction. This recalcitrance to sugar release is a major limitation for cost-effective industrial conversion of lignocellulosic biomass to biofuels. Many literatures had reported the contribution of lignin removal to cellulose accessibility to enzyme, but less to the hemicellulose hydrolysis. Herein, beech xylan with lignin addition, partly delignified sugarcane bagasse (SB), energy sorghum hybrids (ESH) were treated in liquid hot water (LHW) to investigate the effect of lignin on hemicellulose decomposition. The addition of lignin can enhance the low degree of polymerization of xylooligomers production resulted from the acid catalyzed cleavage of lignin-derived acidic products. However, a negative correlation was observed initially between the lignin level and the total xylose yield from ESH. Furthermore, samples with lignin addition or high lignin content had a great resistant to harsh reaction environment, about 93.5% total xylose lost but only 52.3% released due to the lack of lignin protection for the sample with 100% lignin removal.
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Affiliation(s)
- Qiang Yu
- Key Laboratory of Renewable Energy, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China.
| | - Xinshu Zhuang
- Key Laboratory of Renewable Energy, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Zhenhong Yuan
- Key Laboratory of Renewable Energy, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China.
| | - Xiaoying Kong
- Key Laboratory of Renewable Energy, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Wei Qi
- Key Laboratory of Renewable Energy, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Wen Wang
- Key Laboratory of Renewable Energy, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Qiong Wang
- Key Laboratory of Renewable Energy, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academic of Sciences, Beijing 100039, China
| | - Xuesong Tan
- Key Laboratory of Renewable Energy, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China
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20
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Li M, Heckwolf M, Crowe JD, Williams DL, Magee TD, Kaeppler SM, de Leon N, Hodge DB. Cell-wall properties contributing to improved deconstruction by alkaline pre-treatment and enzymatic hydrolysis in diverse maize (Zea mays L.) lines. JOURNAL OF EXPERIMENTAL BOTANY 2015; 66:4305-15. [PMID: 25871649 PMCID: PMC4493778 DOI: 10.1093/jxb/erv016] [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] [Indexed: 05/05/2023]
Abstract
A maize (Zea mays L. subsp. mays) diversity panel consisting of 26 maize lines exhibiting a wide range of cell-wall properties and responses to hydrolysis by cellulolytic enzymes was employed to investigate the relationship between cell-wall properties, cell-wall responses to mild NaOH pre-treatment, and enzymatic hydrolysis yields. Enzymatic hydrolysis of the cellulose in the untreated maize was found to be positively correlated with the water retention value, which is a measure of cell-wall susceptibility to swelling. It was also positively correlated with the lignin syringyl/guaiacyl ratio and negatively correlated with the initial cell-wall lignin, xylan, acetate, and p-coumaric acid (pCA) content, as well as pCA released from the cell wall by pre-treatment. The hydrolysis yield following pre-treatment exhibited statistically significant negative correlations to the lignin content after pre-treatment and positive correlations to the solubilized ferulic acid and pCA. Several unanticipated results were observed, including a positive correlation between initial lignin and acetate content, lack of correlation between acetate content and initial xylan content, and negative correlation between each of these three variables to the hydrolysis yields for untreated maize. Another surprising result was that pCA release was negatively correlated with hydrolysis yields for untreated maize and, along with ferulic acid release, was positively correlated with the pre-treated maize hydrolysis yields. This indicates that these properties that may negatively contribute to the recalcitrance in untreated cell walls may positively contribute to their deconstruction by alkaline pre-treatment.
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Affiliation(s)
- Muyang Li
- Department of Biosystems & Agricultural Engineering, Michigan State University, East Lansing, MI 48824, USA DOE-Great Lakes Bioenergy Research Center, 1552 University Ave., Madison, WI 53703, USA
| | - Marlies Heckwolf
- DOE-Great Lakes Bioenergy Research Center, 1552 University Ave., Madison, WI 53703, USA
| | - Jacob D Crowe
- Department of Chemical Engineering & Materials Science, Michigan State University, East Lansing, MI 48824, USA
| | - Daniel L Williams
- DOE-Great Lakes Bioenergy Research Center, 1552 University Ave., Madison, WI 53703, USA Department of Chemical Engineering & Materials Science, Michigan State University, East Lansing, MI 48824, USA
| | - Timothy D Magee
- Department of Chemical Engineering & Materials Science, Michigan State University, East Lansing, MI 48824, USA
| | - Shawn M Kaeppler
- DOE-Great Lakes Bioenergy Research Center, 1552 University Ave., Madison, WI 53703, USA Department of Agronomy, University of Wisconsin-Madison, Madison, WI 53706-1597, USA
| | - Natalia de Leon
- DOE-Great Lakes Bioenergy Research Center, 1552 University Ave., Madison, WI 53703, USA Department of Agronomy, University of Wisconsin-Madison, Madison, WI 53706-1597, USA
| | - David B Hodge
- Department of Biosystems & Agricultural Engineering, Michigan State University, East Lansing, MI 48824, USA DOE-Great Lakes Bioenergy Research Center, 1552 University Ave., Madison, WI 53703, USA Department of Chemical Engineering & Materials Science, Michigan State University, East Lansing, MI 48824, USA Division of Sustainable Process Engineering, Luleå University of Technology, Luleå, Sweden 97187
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21
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Kim Y, Kreke T, Ko JK, Ladisch MR. Hydrolysis‐determining substrate characteristics in liquid hot water pretreated hardwood. Biotechnol Bioeng 2015; 112:677-87. [DOI: 10.1002/bit.25465] [Citation(s) in RCA: 103] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Revised: 09/04/2014] [Accepted: 09/08/2014] [Indexed: 11/11/2022]
Affiliation(s)
- Youngmi Kim
- Laboratory of Renewable Resources EngineeringPurdue UniversityWest LafayetteIndiana
- Department of Agricultural and Biological EngineeringPurdue UniversityWest LafayetteIndiana
| | - Thomas Kreke
- Laboratory of Renewable Resources EngineeringPurdue UniversityWest LafayetteIndiana
- Department of Agricultural and Biological EngineeringPurdue UniversityWest LafayetteIndiana
| | - Ja Kyong Ko
- Laboratory of Renewable Resources EngineeringPurdue UniversityWest LafayetteIndiana
- Department of Agricultural and Biological EngineeringPurdue UniversityWest LafayetteIndiana
| | - Michael R. Ladisch
- Laboratory of Renewable Resources EngineeringPurdue UniversityWest LafayetteIndiana
- Department of Agricultural and Biological EngineeringPurdue UniversityWest LafayetteIndiana
- Weldon School of Biomedical EngineeringPurdue UniversityWest LafayetteIndiana47907
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Yu G, Yano S, Inoue H, Inoue S, Wang J, Endo T. Structural insights into rice straw pretreated by hot-compressed water in relation to enzymatic hydrolysis. Appl Biochem Biotechnol 2014; 174:2278-94. [PMID: 25178420 DOI: 10.1007/s12010-014-1199-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Accepted: 08/22/2014] [Indexed: 11/29/2022]
Abstract
Pretreatment-induced structural alteration is critical in influencing the rate and extent of enzymatic saccharification of lignocellulosic biomass. The present work has investigated structural features of rice straw pretreated by hot-compressed water (HCW) from 140 to 240 °C for 10 or 30 min and enzymatic hydrolysis profiles of pretreated rice straw. Compositional profiles of pretreated rice straw were examined to offer the basis for structural changes. The wide-angle X-ray diffraction analysis revealed possible modification in crystalline microstructure of cellulose and the severity-dependent variation of crystallinity. The specific surface area (SSA) of pretreated samples was able to achieve more than 10-fold of that of the raw material and was in linear relationship with the removal of acetyl groups and xylan. The glucose yield by enzymatic hydrolysis of pretreated materials correlated linearly with the SSA increase and the dissolution of acetyl and xylan. A quantitatively intrinsic relationship was suggested to exist between enzymatic hydrolysis and the extraction of hemicellulose components in hydrothermally treated rice straw, and SSA was considered one important structural parameter signaling the efficiency of enzymatic digestibility in HCW-treated materials in which hemicellulose removal and lignin redistribution happened.
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Affiliation(s)
- Guoce Yu
- Biomass Refinery Research Center, National Institute of Advanced Industrial Science and Technology, 3-11-32 Kagamiyama, Higashi-Hiroshima, 739-0046, Japan,
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23
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Pérez-Boada M, Prieto A, Prinsen P, Forquin-Gomez MP, del Río JC, Gutiérrez A, Martínez ÁT, Faulds CB. Enzymatic degradation of Elephant grass (Pennisetum purpureum) stems: influence of the pith and bark in the total hydrolysis. BIORESOURCE TECHNOLOGY 2014; 167:469-75. [PMID: 25006023 DOI: 10.1016/j.biortech.2014.06.018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2014] [Revised: 06/05/2014] [Accepted: 06/07/2014] [Indexed: 05/11/2023]
Abstract
The internal pith of a high energy plant, Elephant grass (EG), was more extensively degraded (>50% dry matter) compared to the outer cortex (31%) or the whole stem (35%) by an enzyme preparation from Humicola insolens, Ultraflo. Reducing sugars and acetic acid release from the pith was also higher compared to the cortex. Supplementation of Ultraflo with a type-C feruloyl esterase increased the level of deacetylation but also led to reduced solubilisation. The addition of 20% dimethyl sulfoxide (DMSO) as a co-solvent also reduced the solubility of EG by Ultraflo, although acetic acid release was increased, complimenting previous results found on model substrates. The presence of DMSO was also shown to have a protective effect on xylanase activity but not acetyl esterase activity in Ultraflo. Xylan in the biomass was preferentially solubilised by DMSO, while Ultraflo removed more glucose than xylose.
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Affiliation(s)
- Marta Pérez-Boada
- Centro de Investigaciones Biológicas, Campus Universidad, Ramiro de Maeztu 9, 28040 Madrid, Spain.
| | - Alicia Prieto
- Centro de Investigaciones Biológicas, Campus Universidad, Ramiro de Maeztu 9, 28040 Madrid, Spain.
| | - Pepijn Prinsen
- Department of Plant Biotechnology, Instituto de Recursos Naturales y Agrobiológicas de Sevilla, CSIC, Sevilla, Spain.
| | - Marie-Pierre Forquin-Gomez
- INRA, UMR 1163 Biotechnologie des Champignons Filamenteux, 163 avenue de Luminy, 13288 Marseille cedex 09, France; Aix-Marseille Université, POLYTECH Marseille, UMR 1163 Biotechnologie des Champignons Filamenteux, 163 avenue de Luminy, 13288 Marseille cedex 09, France.
| | - José Carlos del Río
- Department of Plant Biotechnology, Instituto de Recursos Naturales y Agrobiológicas de Sevilla, CSIC, Sevilla, Spain.
| | - Ana Gutiérrez
- Department of Plant Biotechnology, Instituto de Recursos Naturales y Agrobiológicas de Sevilla, CSIC, Sevilla, Spain.
| | - Ángel T Martínez
- Centro de Investigaciones Biológicas, Campus Universidad, Ramiro de Maeztu 9, 28040 Madrid, Spain.
| | - Craig B Faulds
- Centro de Investigaciones Biológicas, Campus Universidad, Ramiro de Maeztu 9, 28040 Madrid, Spain; INRA, UMR 1163 Biotechnologie des Champignons Filamenteux, 163 avenue de Luminy, 13288 Marseille cedex 09, France; Aix-Marseille Université, POLYTECH Marseille, UMR 1163 Biotechnologie des Champignons Filamenteux, 163 avenue de Luminy, 13288 Marseille cedex 09, France.
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Peña L, Hohn KL, Li J, Sun XS, Wang D. Synthesis of Propyl-Sulfonic Acid-Functionalized Nanoparticles as Catalysts for Cellobiose Hydrolysis. ACTA ACUST UNITED AC 2014. [DOI: 10.4236/jbnb.2014.54028] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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25
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Correlation of porous structure, mass transfer and enzymatic hydrolysis of steam exploded corn stover. Chem Eng Sci 2013. [DOI: 10.1016/j.ces.2013.10.022] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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26
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Sun Z, Ge X, Xin D, Zhang J. Hydrolyzabilities of different corn stover fractions after aqueous ammonia pretreatment. Appl Biochem Biotechnol 2013; 172:1506-16. [PMID: 24222503 DOI: 10.1007/s12010-013-0643-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2013] [Accepted: 10/30/2013] [Indexed: 10/26/2022]
Abstract
The effect of aqueous ammonia pretreatment on the hydrolysis of different corn stover fractions (rind, husk, leaf, and pith) by xylanase (XYL) with cellulases (CELs) was evaluated. The aqueous ammonia pretreatment had excellent delignification ability (above 66%) for different corn stover fractions. The corn rind exhibited the lowest susceptibility to aqueous ammonia pretreatment. The pretreated rind showed the lowest hydrolyzability by CEL and XYL, which was supported by a high content of crystalline cellulose in the hydrolyzed residues of rind, as confirmed by X-ray diffraction (XRD). With the addition of 1 mg XYL/g dry matter, a high glucose yield (above 90%) could be obtained from the pretreated rind by CEL. The results revealed that a high hydrolyzate yield of corn rind after aqueous ammonia pretreatment could be obtained with 1 mg xylanase/g dry matter, showing that aqueous ammonia pretreatment and xylanase addition to cellulases have great potential for the efficient hydrolysis of corn stover without previous fractionation.
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Affiliation(s)
- Zongping Sun
- College of Forestry, Northwest A&F University, 3 Taicheng Road, Yangling, 712100, China
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Cao G, Ximenes E, Nichols NN, Zhang L, Ladisch M. Biological abatement of cellulase inhibitors. BIORESOURCE TECHNOLOGY 2013; 146:604-610. [PMID: 23973982 DOI: 10.1016/j.biortech.2013.07.112] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2013] [Revised: 07/19/2013] [Accepted: 07/24/2013] [Indexed: 06/02/2023]
Abstract
Removal of enzyme inhibitors released during lignocellulose pretreatment is essential for economically feasible biofuel production. We tested bio-abatement to mitigate enzyme inhibitor effects observed in corn stover liquors after pretreatment with either dilute acid or liquid hot water at 10% (w/v) solids. Bio-abatement of liquors was followed by enzymatic hydrolysis of cellulose. To distinguish between inhibitor effects on enzymes and recalcitrance of the substrate, pretreated corn stover solids were removed and replaced with 1% (w/v) Solka Floc. Cellulose conversion in the presence of bio-abated liquors from dilute acid pretreatment was 8.6% (0.1x enzyme) and 16% (1x enzyme) higher than control (non-abated) samples. In the presence of bio-abated liquor from liquid hot water pretreated corn stover, 10% (0.1x enzyme) and 13% (1x enzyme) higher cellulose conversion was obtained compared to control. Bio-abatement yielded improved enzyme hydrolysis in the same range as that obtained using a chemical (overliming) method for mitigating inhibitors.
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Affiliation(s)
- Guangli Cao
- Laboratory of Renewable Resources Engineering, Purdue University, West Lafayette, IN 47907-2032, United States; Department of Life Science and Technology, Harbin Institute of Technology, Harbin 150001, China
| | - Eduardo Ximenes
- Laboratory of Renewable Resources Engineering, Purdue University, West Lafayette, IN 47907-2032, United States
| | - Nancy N Nichols
- Bioenergy Research Unit, National Center for Agricultural Utilization Research, Agricultural Research Service, USDA, 1815 N. University Street, Peoria, IL 61604, United States
| | - Leyu Zhang
- Laboratory of Renewable Resources Engineering, Purdue University, West Lafayette, IN 47907-2032, United States
| | - Michael Ladisch
- Laboratory of Renewable Resources Engineering, Purdue University, West Lafayette, IN 47907-2032, United States.
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Maziero P, Jong J, Mendes FM, Gonçalves AR, Eder M, Driemeier C. Tissue-specific cell wall hydration in sugarcane stalks. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2013; 61:5841-5847. [PMID: 23738592 DOI: 10.1021/jf401243c] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Plant cell walls contain water, especially under biological and wet processing conditions. The present work characterizes this water in tissues of sugarcane stalks. Environmental scanning electron microscopy shows tissue deformation upon drying. Dynamic vapor sorption determines the equilibrium and kinetics of moisture uptake. Thermoporometry by differential scanning calorimetry quantifies water in nanoscale pores. Results show that cell walls from top internodes of stalks are more deformable, slightly more sorptive to moisture, and substantially more porous. These differences of top internode are attributed to less lignified walls, which is confirmed by lower infrared spectral signal from aromatics. Furthermore, cell wall nanoscale porosity, an architectural and not directly compositional characteristic, is shown to be tissue-specific. Nanoscale porosities are ranked as follows: pith parenchyma > pith vascular bundles > rind. This ranking coincides with wall reactivity and digestibility in grasses, suggesting that nanoscale porosity is a major determinant of wall recalcitrance.
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Affiliation(s)
- Priscila Maziero
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol, CTBE/CNPEM , 13083-970 Campinas, São Paulo, Brazil
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Kumar D, Murthy GS. Stochastic molecular model of enzymatic hydrolysis of cellulose for ethanol production. BIOTECHNOLOGY FOR BIOFUELS 2013; 6:63. [PMID: 23638989 PMCID: PMC3664589 DOI: 10.1186/1754-6834-6-63] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2012] [Accepted: 04/29/2013] [Indexed: 05/11/2023]
Abstract
BACKGROUND During cellulosic ethanol production, cellulose hydrolysis is achieved by synergistic action of cellulase enzyme complex consisting of multiple enzymes with different mode of actions. Enzymatic hydrolysis of cellulose is one of the bottlenecks in the commercialization of the process due to low hydrolysis rates and high cost of enzymes. A robust hydrolysis model that can predict hydrolysis profile under various scenarios can act as an important forecasting tool to improve the hydrolysis process. However, multiple factors affecting hydrolysis: cellulose structure and complex enzyme-substrate interactions during hydrolysis make it diffucult to develop mathematical kinetic models that can simulate hydrolysis in presence of multiple enzymes with high fidelity. In this study, a comprehensive hydrolysis model based on stochastic molecular modeling approch in which each hydrolysis event is translated into a discrete event is presented. The model captures the structural features of cellulose, enzyme properties (mode of actions, synergism, inhibition), and most importantly dynamic morphological changes in the substrate that directly affect the enzyme-substrate interactions during hydrolysis. RESULTS Cellulose was modeled as a group of microfibrils consisting of elementary fibrils bundles, where each elementary fibril was represented as a three dimensional matrix of glucose molecules. Hydrolysis of cellulose was simulated based on Monte Carlo simulation technique. Cellulose hydrolysis results predicted by model simulations agree well with the experimental data from literature. Coefficients of determination for model predictions and experimental values were in the range of 0.75 to 0.96 for Avicel hydrolysis by CBH I action. Model was able to simulate the synergistic action of multiple enzymes during hydrolysis. The model simulations captured the important experimental observations: effect of structural properties, enzyme inhibition and enzyme loadings on the hydrolysis and degree of synergism among enzymes. CONCLUSIONS The model was effective in capturing the dynamic behavior of cellulose hydrolysis during action of individual as well as multiple cellulases. Simulations were in qualitative and quantitative agreement with experimental data. Several experimentally observed phenomena were simulated without the need for any additional assumptions or parameter changes and confirmed the validity of using the stochastic molecular modeling approach to quantitatively and qualitatively describe the cellulose hydrolysis.
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Affiliation(s)
- Deepak Kumar
- Biological and Ecological Engineering, Oregon State University, Corvallis, USA
| | - Ganti S Murthy
- Biological and Ecological Engineering, Oregon State University, Corvallis, USA
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X-ray scattering studies of lignocellulosic biomass: A review. Carbohydr Polym 2013; 94:904-17. [DOI: 10.1016/j.carbpol.2013.02.008] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2012] [Revised: 02/04/2013] [Accepted: 02/09/2013] [Indexed: 11/24/2022]
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Yu Q, Zhuang X, Lv S, He M, Zhang Y, Yuan Z, Qi W, Wang Q, Wang W, Tan X. Liquid hot water pretreatment of sugarcane bagasse and its comparison with chemical pretreatment methods for the sugar recovery and structural changes. BIORESOURCE TECHNOLOGY 2013; 129:592-8. [PMID: 23306094 DOI: 10.1016/j.biortech.2012.11.099] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2012] [Revised: 11/21/2012] [Accepted: 11/22/2012] [Indexed: 05/23/2023]
Abstract
Liquid hot water (LHW), dilute hydrochloric acid (HCl) and dilute sodium hydroxide (NaOH) were applied to sugarcane bagasse (SB). Application of the same analytical methods and material balance approaches facilitated meaningful comparisons of glucose and xylose yields from combined pretreatment and enzymatic hydrolysis. All pretreatments enhanced sugar recovery from pretreatment and subsequent enzymatic hydrolysis substantially compared to untreated sugarcane bagasse. Adding Tween80 in the enzymatic hydrolysis process increased the conversion level of glucan/xylan by 0.3-fold, especially for the low pH pretreatment where more lignin was left in the solids. The total sugar recovery from sugarcane bagasse with the coupled operations of pretreatment and 72 h enzymatic digestion reached 71.6% for LHW process, 76.6% for HCl pretreatment and 77.3% for NaOH pretreatment. Different structural changes at the plant tissue, cellular, and cell wall levels might be responsible for the different enzymatic digestibility. Furthermore, a combined LHW and aqueous ammonia pretreatment was proposed to reduce energy input and enhance the sugar recovery.
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Affiliation(s)
- Qiang Yu
- Key Laboratory of Renewable Energy and Gas Hydrate, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China.
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Cell-type-dependent enzymatic hydrolysis of palm residues: chemical and surface characterization of fibers and parenchyma cells. Biotechnol Lett 2012; 35:213-8. [PMID: 23143173 DOI: 10.1007/s10529-012-1079-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2012] [Accepted: 10/04/2012] [Indexed: 10/27/2022]
Abstract
Chemical and surface characteristics of sulfite-pretreated royal palm sheath (RPS) fibers and parenchyma cells were investigated in order to study cell-type-dependent biomass hydrolysis by cellulase. Size, chemical composition, cellulose crystallinity and the exposure of cellulose microfibrils in pretreated RPS biomass affected the enzymatic accessibility and digestibility of different cell-type substrates.
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Zhang X, Qiu W, Chen H. Enhancing the hydrolysis and acidification of steam-exploded cornstalks by intermittent pH adjustment with an enriched microbial community. BIORESOURCE TECHNOLOGY 2012; 123:30-35. [PMID: 22929742 DOI: 10.1016/j.biortech.2012.07.054] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2012] [Revised: 07/13/2012] [Accepted: 07/16/2012] [Indexed: 06/01/2023]
Abstract
Intermittent pH adjustment was used to increase the degradation rate of steam-exploded cornstalks (SEC) and the production of organic acids by an enriched microbial community. The results showed that the degradation rate of SEC was as high as 75% and not affected by the intermittent pH adjustment within the range of 7.0-9.0. However, the total concentration of major water soluble metabolites (acetate and propionate) were increased with pH enhancement, showing the results of 1.86gL(-1) for pH 7.0, 2.04gL(-1) for pH 8.0 and 3.32gL(-1) for pH 9.0 after 84h of fermentation. Based on 16s rDNA analysis by denaturing gradient gel electrophoresis (DGGE), different strains were dominant due to pH shift by intermittent adjustment, which would consequently cause the change in fermentation pattern. Intermittent pH adjustment was considered to be a useful way to enhance bioconversion potentiality of lignocellulose.
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Affiliation(s)
- Xiang Zhang
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
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34
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Caicedo HM, Dempere LA, Vermerris W. Template-mediated synthesis and bio-functionalization of flexible lignin-based nanotubes and nanowires. NANOTECHNOLOGY 2012; 23:105605. [PMID: 22362196 DOI: 10.1088/0957-4484/23/10/105605] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Limitations of cylindrical carbon nanotubes based on the buckminsterfullerene structure as delivery vehicles for therapeutic agents include their chemical inertness, sharp edges and toxicological concerns. As an alternative, we have developed lignin-based nanotubes synthesized in a sacrificial template of commercially available alumina membranes. Lignin is a complex phenolic plant cell wall polymer that is generated as a waste product from paper mills and biorefineries that process lignocellulosic biomass into fuels and chemicals. We covalently linked isolated lignin to the inner walls of activated alumina membranes and then added layers of dehydrogenation polymer onto this base layer via a peroxidase-catalyzed reaction. By using phenolic monomers displaying different reactivities, we were able to change the thickness of the polymer layer deposited within the pores, resulting in the synthesis of nanotubes with a wall thickness of approximately 15 nm or nanowires with a nominal diameter of 200 nm. These novel nanotubes are flexible and can be bio-functionalized easily and specifically, as shown by in vitro assays with biotin and Concanavalin A. Together with their intrinsic optical properties, which can also be varied as a function of their chemical composition, these lignin-based nanotubes are expected to enable a variety of new applications including as delivery systems that can be easily localized and imaged after uptake by living cells.
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Affiliation(s)
- Hector M Caicedo
- Genetics Institute, University of Florida, Gainesville, FL 32610-3610, USA
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