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Huang W, Shi Y, Yan H, Wang H, Wu D, Grierson D, Chen K. The calcium-mediated homogalacturonan pectin complexation in cell walls contributes the firmness increase in loquat fruit during postharvest storage. J Adv Res 2022:S2090-1232(22)00211-9. [PMID: 36198382 DOI: 10.1016/j.jare.2022.09.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 09/11/2022] [Accepted: 09/24/2022] [Indexed: 11/30/2022] Open
Abstract
INTRODUCTION Postharvest textural changes in fruit are mainly divided into softening and lignification. Loquat fruit could have severe lignification with increased firmness during postharvest storage. Pectin is mainly associated with the postharvest softening of fruit, but some studies also found that pectin could be involved in strengthening the mechanical properties of the plant. OBJECTIVES This study focused on characterizing the dynamics of pectin and its complexation in the cell wall of lignified loquat fruit during postharvest storage, and how these changes could influence fruit firmness. METHODS The homogalacturonan (HG) pectin in the cell wall of loquat fruit was identified using monoclonal antibodies. An oligogalacturonide (OG) probe was used to label the egg-box structure formed by Ca2+ cross-linking with low-methylesterified HG. An exogenous injection was used to verify the role of egg-box structures in the firmness increase in loquat fruit. RESULTS The JIM5 antibody revealed that low-methylesterified HG accumulated in the tricellular junctions and middle lamella of loquat fruit that had severe lignification symptoms. The pectin methylesterase (PME) activity increased during the early stages of storage at 0°C, and the calcium-pectate content and flesh firmness constantly increased during storage. The OG probe demonstrated the accumulation of egg-box structures at the cellular level. The exogenous injection of PME and Ca2+ into the loquat flesh led to an increase in firmness with more low-methylesterified HG and egg-box structure signals. CONCLUSION PME-mediated demethylesterification generated large amounts of low-methylesterified HG in the cell wall. This low-methylesterified HG further cross-linked with Ca2+ to form egg-box structures. The pectin-involved complexations then contributed to the increased firmness in loquat fruit. Overall, besides being involved in fruit softening, pectin could also be involved in strengthening the mechanical properties of postharvest fruit. This study provides new ideas for obtaining a better texture of postharvest loquat fruits based on pectin regulation.
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Affiliation(s)
- Weinan Huang
- College of Agriculture and Biotechnology/Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology/The State Agriculture Ministry Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Zhejiang University, 310058 Hangzhou, P. R. China; Zhejiang University Zhongyuan Institute, Zhengzhou 450000, P. R. China
| | - Yanna Shi
- College of Agriculture and Biotechnology/Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology/The State Agriculture Ministry Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Zhejiang University, 310058 Hangzhou, P. R. China
| | - He Yan
- College of Life Sciences, South China Agricultural University, Guangzhou 510642, P. R. China
| | - Hao Wang
- College of Life Sciences, South China Agricultural University, Guangzhou 510642, P. R. China
| | - Di Wu
- College of Agriculture and Biotechnology/Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology/The State Agriculture Ministry Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Zhejiang University, 310058 Hangzhou, P. R. China; Zhejiang University Zhongyuan Institute, Zhengzhou 450000, P. R. China.
| | - Donald Grierson
- College of Agriculture and Biotechnology/Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology/The State Agriculture Ministry Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Zhejiang University, 310058 Hangzhou, P. R. China; Plant and Crop Sciences Division, School of Biosciences, University of Nottingham, Loughborough, UK
| | - Kunsong Chen
- College of Agriculture and Biotechnology/Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology/The State Agriculture Ministry Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Zhejiang University, 310058 Hangzhou, P. R. China; Zhejiang University Zhongyuan Institute, Zhengzhou 450000, P. R. China
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Khaytmetova SB, Turaev AS, Khalilova GA. Isolation and Physicochemical Characteristics of Pectin from Inonotus Hispidus. POLYMER SCIENCE SERIES B 2022. [DOI: 10.1134/s1560090422700221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Giummarella N, Balakshin M, Koutaniemi S, Kärkönen A, Lawoko M. Nativity of lignin carbohydrate bonds substantiated by biomimetic synthesis. JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:5591-5601. [PMID: 31294799 PMCID: PMC6812735 DOI: 10.1093/jxb/erz324] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Accepted: 06/28/2019] [Indexed: 06/09/2023]
Abstract
The question of whether lignin is covalently linked to carbohydrates in native wood, forming what is referred to as lignin-carbohydrate complexes (LCCs), still lacks unequivocal proof. This is mainly due to the need to isolate lignin from woody materials prior to analysis, under conditions leading to partial chemical modification of the native wood polymers. Thus, the correlation between the structure of the isolated LCCs and LCCs in situ remains open. As a way to circumvent the problematic isolation, biomimicking lignin polymerization in vivo and in vitro is an interesting option. Herein, we report the detection of lignin-carbohydrate bonds in the extracellular lignin formed by tissue-cultured Norway spruce cells, and in modified biomimetic lignin synthesis (dehydrogenation polymers). Semi-quantitative 2D heteronuclear singular quantum coherence (HSQC)-, 31P -, and 13C-NMR spectroscopy were applied as analytical tools. Combining results from these systems, four types of lignin-carbohydrate bonds were detected; benzyl ether, benzyl ester, γ-ester, and phenyl glycoside linkages, providing direct evidence of lignin-carbohydrate bond formation in biomimicked lignin polymerization. Based on our findings, we propose a sequence for lignin-carbohydrate bond formation in plant cell walls.
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Affiliation(s)
- Nicola Giummarella
- Fiber and Polymer Technology, Wallenberg Wood Science Center, Royal Institute of Technology, Stockholm, Sweden
| | | | - Sanna Koutaniemi
- Department of Food and Environmental Chemistry, University of Helsinki, Finland
| | - Anna Kärkönen
- Department of Agricultural Sciences, Viikki Plant Science Centre, University of Helsinki, Finland
- Natural Resources Institute Finland, Production Systems, Plant Genetics, Helsinki, Finland
| | - Martin Lawoko
- Fiber and Polymer Technology, Wallenberg Wood Science Center, Royal Institute of Technology, Stockholm, Sweden
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Damm T, Pattathil S, Günl M, Jablonowski ND, O'Neill M, Grün KS, Grande PM, Leitner W, Schurr U, Usadel B, Klose H. Insights into cell wall structure of Sida hermaphrodita and its influence on recalcitrance. Carbohydr Polym 2017; 168:94-102. [PMID: 28457468 DOI: 10.1016/j.carbpol.2017.03.062] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Revised: 02/27/2017] [Accepted: 03/18/2017] [Indexed: 01/25/2023]
Abstract
The perennial plant Sida hermaphrodita (Sida) is attracting attention as potential energy crop. Here, the first detailed view on non-cellulosic Sida cell wall polysaccharide composition, structure and architecture is given. Cell walls were prepared from Sida stems and sequentially extracted with aqueous buffers and alkali. The structures of the quantitatively predominant polysaccharides present in each fraction were determined by biochemical characterization, glycome profiling and mass spectrometry. The amounts of glucose released by Accellerase-1500® treatment of the cell wall and the cell wall residue remaining after each extraction were used to assess the roles of pectin and hemicellulose in the recalcitrance of Sida biomass. 4-O-Methyl glucuronoxylan with a low proportion of side substitutions was identified as the major non-cellulosic glycan component of Sida stem cell walls. Pectic polysaccharides and xylans were found to be associated with lignin, suggesting that these polysaccharides have roles in Sida cell wall recalcitrance to enzymatic hydrolysis.
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Affiliation(s)
- Tatjana Damm
- Institute for Botany and Molecular Genetics, RWTH Aachen University, Worringer Weg 3, 52074 Aachen, Germany; Bioeconomy Science Center (BioSC), c/o Forschungszentrum Jülich, 52425 Jülich, Germany.
| | - Sivakumar Pattathil
- Complex Carbohydrate Research Center, The University of Georgia, 315 Riverbend Rd. Athens, GA, USA.
| | - Markus Günl
- Institute of Bio- and Geosciences, IBG-2: Plant Sciences, Forschungszentrum Jülich, Leo- Brandt-Straße, 52425 Jülich, Germany.
| | - Nicolai David Jablonowski
- Bioeconomy Science Center (BioSC), c/o Forschungszentrum Jülich, 52425 Jülich, Germany; Institute of Bio- and Geosciences, IBG-2: Plant Sciences, Forschungszentrum Jülich, Leo- Brandt-Straße, 52425 Jülich, Germany.
| | - Malcolm O'Neill
- Complex Carbohydrate Research Center, The University of Georgia, 315 Riverbend Rd. Athens, GA, USA.
| | - Katharina Susanne Grün
- Institute for Botany and Molecular Genetics, RWTH Aachen University, Worringer Weg 3, 52074 Aachen, Germany.
| | - Philipp Michael Grande
- Institute for Technical and Macromolecular Chemistry, RWTH Aachen University, Worringer Weg 1-2, 52074 Aachen Germany.
| | - Walter Leitner
- Institute for Technical and Macromolecular Chemistry, RWTH Aachen University, Worringer Weg 1-2, 52074 Aachen Germany; Max-Planck-Institut für Kohlenforschung, 45470 Mülheim an der Ruhr, Germany.
| | - Ulrich Schurr
- Bioeconomy Science Center (BioSC), c/o Forschungszentrum Jülich, 52425 Jülich, Germany; Institute of Bio- and Geosciences, IBG-2: Plant Sciences, Forschungszentrum Jülich, Leo- Brandt-Straße, 52425 Jülich, Germany.
| | - Björn Usadel
- Institute for Botany and Molecular Genetics, RWTH Aachen University, Worringer Weg 3, 52074 Aachen, Germany; Bioeconomy Science Center (BioSC), c/o Forschungszentrum Jülich, 52425 Jülich, Germany; Institute of Bio- and Geosciences, IBG-2: Plant Sciences, Forschungszentrum Jülich, Leo- Brandt-Straße, 52425 Jülich, Germany.
| | - Holger Klose
- Institute for Botany and Molecular Genetics, RWTH Aachen University, Worringer Weg 3, 52074 Aachen, Germany; Bioeconomy Science Center (BioSC), c/o Forschungszentrum Jülich, 52425 Jülich, Germany.
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Chen J, Liu W, Liu CM, Li T, Liang RH, Luo SJ. Pectin Modifications: A Review. Crit Rev Food Sci Nutr 2015; 55:1684-98. [DOI: 10.1080/10408398.2012.718722] [Citation(s) in RCA: 120] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Herrero J, Esteban-Carrasco A, Zapata JM. Looking for Arabidopsis thaliana peroxidases involved in lignin biosynthesis. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2013; 67:77-86. [PMID: 23545205 DOI: 10.1016/j.plaphy.2013.02.019] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2012] [Accepted: 02/19/2013] [Indexed: 05/20/2023]
Abstract
Monolignol polymerization into lignin is catalyzed by peroxidases or laccases. Recently, a Zinnia elegans peroxidase (ZePrx) that is considered responsible for monolignol polymerization in this plant has been molecularly and functionally characterized. Nevertheless, Arabidopsis thaliana has become an alternative model plant for studies of lignification, filling the gaps that may occur with Z. elegans. The arabidopsis genome offers the possibility of performing bioinformatic analyses and data mining that are not yet feasible with other plant species, in order to obtain preliminary evidence on the role of genes and proteins. In our search for arabidopsis homologs to the ZePrx, we performed an exhaustive in silico characterization of everything from the protein to the transcript of Arabidopsis thaliana peroxidases (AtPrxs) homologous to ZePrx, with the aim of identifying one or more peroxidases that may be involved in monolignol polymerization. Nine peroxidases (AtPrx 4, 5, 52, 68, 67, 36, 14, 49 and 72) with an E-value greater than 1e-80 with ZePrx were selected for this study. The results demonstrate that a high level of 1D, 2D and 3D homology between these AtPrxs and ZePrx are not always accompanied by the presence of the same electrostatic and mRNA properties that indicate a peroxidase is involved in lignin biosynthesis. In summary, we can confirm that the peroxidases involved in lignification are among AtPrx 4, 52, 49 and 72. Their structural and mRNA features indicate that exert their action in the cell wall similar to ZePrx.
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Affiliation(s)
- Joaquín Herrero
- Department of Plant Biology, University of Alcalá, E-28871 Alcalá de Henares, Madrid, Spain.
| | | | - José Miguel Zapata
- Department of Plant Biology, University of Alcalá, E-28871 Alcalá de Henares, Madrid, Spain.
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Xylan as by-product of biorefineries: Characteristics and potential use for food applications. Food Hydrocoll 2011. [DOI: 10.1016/j.foodhyd.2011.04.005] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Habrant A, Gaillard C, Ralet MC, Lairez D, Cathala B. Relation between chemical structure and supramolecular organization of synthetic lignin-pectin particles. Biomacromolecules 2010; 10:3151-6. [PMID: 19894766 DOI: 10.1021/bm900950r] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Anouck Habrant
- UMR614 Fractionnement des Agro-Ressources et Environement, INRA, Université de Reims Champagne Ardennes, Reims, France
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Reale S, Attanasio F, Spreti N, De Angelis F. Lignin Chemistry: Biosynthetic Study and Structural Characterisation of Coniferyl Alcohol Oligomers Formed In Vitro in a Micellar Environment. Chemistry 2010; 16:6077-87. [DOI: 10.1002/chem.200903302] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Day A, Ruel K, Neutelings G, Crônier D, David H, Hawkins S, Chabbert B. Lignification in the flax stem: evidence for an unusual lignin in bast fibers. PLANTA 2005; 222:234-45. [PMID: 15968509 DOI: 10.1007/s00425-005-1537-1] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2004] [Accepted: 01/29/2005] [Indexed: 05/03/2023]
Abstract
In the context of our research on cell wall formation and maturation in flax (Linum usitatissimum L) bast fibers, we (1) confirmed the presence of lignin in bast fibers and (2) quantified and characterized the chemical nature of this lignin at two developmental stages. Histochemical methods (Weisner and Maüle reagents and KMnO(4)-staining) indicating the presence of lignin in bast fibers at the light and electron microscope levels were confirmed by chemical analyses (acetyl bromide). In general, the lignin content in flax bast fibers varied between 1.5% and 4.2% of the dry cell wall residues (CWRs) as compared to values varying between 23.7% and 31.4% in flax xylem tissues. Immunological and chemical analyses (thioacidolysis and nitrobenzene oxidation) indicated that both flax xylem- and bast fiber-lignins were rich in guaiacyl (G) units with S/G values inferior to 0.5. In bast fibers, the highly sensitive immunological probes allowed the detection of condensed guaiacyl-type (G) lignins in the middle lamella, cell wall junctions, and in the S1 layer of the secondary wall. In addition, lower quantities of mixed guaiacyl-syringyl (GS) lignins could be detected throughout the secondary cell wall. Chemical analyses suggested that flax bast-fiber lignin is more condensed than the corresponding xylem lignin. In addition, H units represented up to 25% of the monomers released from bast-fiber lignin as opposed to a value of 1% for the corresponding xylem tissue. Such an observation indicates that the structure of flax bast-fiber lignin is significantly different from that of the more typical 'woody plant lignin', thereby suggesting that flax bast fibers represent an interesting system for studying an unusual lignification process.
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Affiliation(s)
- Arnaud Day
- Laboratoire de Physiologie des Parois Végétales, UPRES EA 3568-USC-INRA, UFR de Biologie, USTL, 59655, Villeneuve d'Ascq cedex, France
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Durot N, Pollet B, Lapierre C, Kurek B. Abiotic degradation of lignified cell walls by carbonate and copper salt. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2004; 52:816-822. [PMID: 14969536 DOI: 10.1021/jf030132m] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
This study reports on the destructuration of Wheat straw and Spruce wood cell walls after maceration in potassium carbonate or sodium hydroxide at pH = 10 in the presence of copper acetate. The alkaline treatments had a predominant impact on the wheat straw cell wall components over copper acetate. Either K-carbonate or Na-hydroxide extracted from wheat straw a particular lignin fraction rich in condensed C-C linkages, leading to the unmasking of new ether-linked sub-structures in the cell wall. This unmasking was increased in the presence of copper salt but only in the nonextracted Wheat straw sample incubated in carbonate and not in the corresponding extractive-free sample. This difference was related to the leaching of compounds from the nonextracted cell wall, which could sustain oxidative activity of copper by hindering its precipitation into inactive hydroxide and/or carbonate species. In Spruce wood samples, copper salt was the principal factor impacting on the lignin structure over alkali alone. Its effect was, however, only detected at the level of C-C linked dimers. These results confirmed that unmasking of lignin sub-structures also occurred in Spruce wood, but probably through mechanisms different from that evidenced in Wheat straw.
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Affiliation(s)
- Nathalie Durot
- Equipe Parois Végétales et Matériaux Fibreux, UMR de Fractionnement des Agro-Ressources et Emballages, Institut National de la Recherche Agronomique (INRA), 2 Esplanade Roland Garros, F-51686 Reims Cedex 2, France
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Durot N, Gaudard F, Kurek B. The unmasking of lignin structures in wheat straw by alkali. PHYTOCHEMISTRY 2003; 63:617-623. [PMID: 12809724 DOI: 10.1016/s0031-9422(03)00187-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
This study reports on the structural modifications of wheat straw cell wall promoted by potassium carbonate and sodium hydroxide that lead to the unmasking of some lignin structures. The first impact of the treatments was the extraction of a particular fraction of lignin enriched in C-C linked structures compared to the mean composition in reference wheat straw. Concomitantly, an apparent increase in the amount of lignin monomers released by the cleavage of alkyl-aryl ether bonds was observed in alkali-extracted samples. By summing the amount of ether linked monomers analyzed by thioacidolysis in the solubilized lignin to that found in the extracted wheat straw, an excess of up to 37% is apparent, relative to the corresponding amount in the reference wheat straw. Other modifications of the cell wall were also found. Indeed, a fraction of uronic acids was lost during the treatments and a new fractionation pattern of the lignin-carbohydrate complexes was evidenced. It can thus be concluded that a significant proportion of lignin within the cell wall was unmasked after (i) the selective removal of a particular lignin fraction, (ii) a partial saponification of the esterified fraction of lignin with uronic acids and (iii) a modification of the interactions between the cell wall constituents.
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Affiliation(s)
- Nathalie Durot
- Equipe Parois Végétales et Matériaux Fibreux, UMR de Fractionnement des Agroressources et Emballages, Institut National de la Recherche Agronomique (INRA), 2 Esplanade Roland Garros, F-51686 Reims Cedex 2, France
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Touzel JP, Chabbert B, Monties B, Debeire P, Cathala B. Synthesis and characterization of dehydrogenation polymers in Gluconacetobacter xylinus cellulose and cellulose/pectin composite. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2003; 51:981-986. [PMID: 12568559 DOI: 10.1021/jf020200p] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
To mimic the lignin polymerization process, mats of bacterial cellulose and of a pectin/cellulose composite were used as a host matrix for in vitro polymerization of coniferyl alcohol. A diffusion cell was used to allow the diffusion of both hydrogen peroxide and coniferyl alcohol into the peroxidase impregnated cellulose mats through dialysis membranes. The results indicate that significant polymerization occurs within the mats. The resulting binary and ternary blends were imaged by scanning electron microscopy (SEM) and characterized by chemical means. The presence of pectin induces a better dispersion of the synthetic lignin in the cellulose network and enhances the proportion of alkyl-aryl-ether in the polymer.
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Affiliation(s)
- Jean-Pierre Touzel
- Unité Mixte de Recherche, INRA/URCA, Fractionnement des Agro-Ressources et Emballages, CRA 2 Esp R. Garros, 51686 Reims Cedex, France
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Cathala B, Monties B. Influence of pectins on the solubility and the molar mass distribution of dehydrogenative polymers (DHPs, lignin model compounds). Int J Biol Macromol 2001; 29:45-51. [PMID: 11429188 DOI: 10.1016/s0141-8130(01)00145-3] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Dehydrogenation polymers (DHPs, lignin model compounds) were synthesized in the presence of increasing pectin concentrations using two different methods. The first method ('Zutropfverfahren', ZT) consists in the slow adding of monomers whereas in the second method ('Zulaufverfahren', ZL) all the reactants are added simultaneously. DHPs solubility increases with the pectin concentration in the ZT experiments and remains stable in the ZL experiments. Covalent bonds between pectin and DHP are formed during ZT polymerization resulting in lignin carbohydrate complex (LCC) which keeps the unbound DHPs in solution by the formation of aggregate or micelle-like structures. In contrast LCC are not formed during the ZL process which behave like the DHP reference. The ZT DHP molar masses increase observed is attributed to the reactivity of the high molar mass polymer solubilized by the LCC whereas ZL higher molar mass polymers are precipitated out of the solution and cannot react further.
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Affiliation(s)
- B Cathala
- INRA Umite de Physicochimie et Biotechnologie des Polyméres, Equipe de Biochimie des Macromolécules Végétales, B.P. 224 CRA 2 Esp R. Garros, 51686 Cedex, Reims, France.
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