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Sznaider F, Rojas AM, Stortz CA, Navarro DA. Amidation of arabinoglucuronoxylans to modulate their flow behavior. Carbohydr Polym 2024; 336:122123. [PMID: 38670754 DOI: 10.1016/j.carbpol.2024.122123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 03/22/2024] [Accepted: 04/01/2024] [Indexed: 04/28/2024]
Abstract
Arabinoglucuronoxylans obtained from the exudate of Cercidium praecox (Brea gum) were subjected to an amidation reaction to modulate their flow behavior to obtain a product with similar behavior to gum Arabic. The amidation reaction of the uronic acids present in this exudate was studied using the 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) and N-hydroxysuccinimide (NHS) system with the aim of maximizing product yield and minimizing by-product. An analysis of the significant factors involved in the reaction was carried out and a response surface methodology was conducted to optimize the stoichiometry of the reagents used. It was possible to obtain models for predicting the degree of amidation (DA) of arabinoglucuronoxylans and the formation of by-products. The formation of a secondary product derived from the amino acid β-alanine which has not been reported previously in the reaction with polysaccharides, was described. The flow behavior of an amidated product (DA = 52 %) was determined, showing a pseudoplastic behavior and a decreased Newtonian viscosity (η0 = 36.2 Pa s) at the lowest shear rate range with respect to native product solution (η0 = 115 Pa s). Amidated arabinoglucuronoxylans had a flow behavior more similar to that of gum Arabic.
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Affiliation(s)
- Frank Sznaider
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Consejo Nacional de Investigaciones Científicas y Técnicas, Centro de Investigaciones en Hidratos de Carbono (CIHIDECAR/CONICET), Departamento de Química Orgánica, Ciudad Universitaria, C1428BGA Buenos Aires, Argentina
| | - Ana M Rojas
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Tecnología de Alimentos y Procesos Químicos (ITAPROQ/CONICET-UBA), Departamento de Industrias, Ciudad Universitaria, C1428BGA Buenos Aires, Argentina
| | - Carlos A Stortz
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Consejo Nacional de Investigaciones Científicas y Técnicas, Centro de Investigaciones en Hidratos de Carbono (CIHIDECAR/CONICET), Departamento de Química Orgánica, Ciudad Universitaria, C1428BGA Buenos Aires, Argentina
| | - Diego A Navarro
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Consejo Nacional de Investigaciones Científicas y Técnicas, Centro de Investigaciones en Hidratos de Carbono (CIHIDECAR/CONICET), Departamento de Química Orgánica, Ciudad Universitaria, C1428BGA Buenos Aires, Argentina.
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Ma YS, Kuo FM, Liu TH, Lin YT, Yu J, Wei Y. Exploring keratin composition variability for sustainable thermal insulator design. Int J Biol Macromol 2024; 275:133690. [PMID: 38971280 DOI: 10.1016/j.ijbiomac.2024.133690] [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: 03/10/2024] [Revised: 06/18/2024] [Accepted: 07/03/2024] [Indexed: 07/08/2024]
Abstract
In pursuing sustainable thermal insulation solutions, this study explores the integration of human hair and feather keratin with alginate. The aim is to assess its potential in thermal insulation materials, focusing on the resultant composites' thermal and mechanical characteristics. The investigation uncovers that the type and proportion of keratin significantly influence the composites' porosity and thermal conductivity. Specifically, higher feather keratin content is associated with lesser sulfur and reduced crosslinking due to shorter amino acids, leading to increased porosity and pore sizes. This, in turn, results in a decrease in β-structured hydrogen bond networks, raising non-ordered protein structures and diminishing thermal conductivity from 0.044 W/(m·K) for pure alginate matrices to between 0.033 and 0.038 W/(m·K) for keratin-alginate composites, contingent upon the specific ratio of feather to hair keratin used. Mechanical evaluations further indicate that composites with a higher ratio of hair keratin exhibit an enhanced compressive modulus, ranging from 60 to 77 kPa, demonstrating the potential for tailored mechanical properties to suit various applications. The research underscores the critical role of sulfur content and the crosslinking index within keratin's structures, significantly impacting the thermal and mechanical properties of the matrices. The findings position keratin-based composites as environmentally friendly alternatives to traditional insulation materials.
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Affiliation(s)
- Yu-Shuan Ma
- Department of Chemical Engineering and Biotechnology, National Taipei University of Technology (Taipei Tech), Taipei 106, Taiwan
| | - Fang-Mei Kuo
- Department of Chemical Engineering and Biotechnology, National Taipei University of Technology (Taipei Tech), Taipei 106, Taiwan
| | - Tai-Hung Liu
- Department of Chemical Engineering, College of Engineering, National Taiwan University, Taipei 106, Taiwan
| | - Yu-Ting Lin
- Department of Chemical Engineering, College of Engineering, National Taiwan University, Taipei 106, Taiwan
| | - Jiashing Yu
- Department of Chemical Engineering, College of Engineering, National Taiwan University, Taipei 106, Taiwan.
| | - Yang Wei
- Department of Chemical Engineering and Biotechnology, National Taipei University of Technology (Taipei Tech), Taipei 106, Taiwan; High-value Biomaterials Research and Commercialization Center, National Taipei University of Technology, Taipei, 10608, Taiwan.
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Gürer F, Mohan T, Bračič M, Barlič A, Makuc D, Plavec J, Kleinschek KS, Kargl R. Hyaluronic acid conjugates of glycine peptides and L-tryptophan. Int J Biol Macromol 2024; 274:133301. [PMID: 38914403 DOI: 10.1016/j.ijbiomac.2024.133301] [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: 03/13/2024] [Revised: 06/03/2024] [Accepted: 06/04/2024] [Indexed: 06/26/2024]
Abstract
This work reports about the conjugation of glycine C-terminal ethyl and methyl ester peptides and L-tryptophan methyl ester with sodium hyaluronate in aqueous solutions using the peptide coupling agent DMTMM (or short DMT, 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methyl-morpholinium chloride). Detailed infrared (IR) absorbance and 1H and 13C (2D) NMR studies (heteronuclear multi-bond correlation spectroscopy, HMBC) confirmed covalent and regioselective amide bonds with the D-glucuronate, but also proves the presence of DMT traces in all conjugates. The ethyl ester`s methyl protons on the peptides` C-terminal could be used to quantify the degree of substitution of the peptide on the hyaluronate scaffold by NMR. The ester group also proved stable during conjugation and work-up, and could in some cases be selectively cleaved in water whilst leaving the amide bond intact as shown by potentiometric charge titration, NMR and IR. The conjugates did not influence the capability of human umbilical vein endothelial cells (HUVECs) to reduce MTS (5-[3-(carboxymethoxy)phenyl]-3-(4,5-dimethyl-2-thiazolyl)-2-(4-sulfophenyl)-2H-tetrazolium inner salt) to a formazan dye, which points towards a low cytotoxicity for the obtained products. The conjugation method and products could be tested for tissue engineering gels or drug delivery purposes with alternative, biologically active peptides.
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Affiliation(s)
- Fazilet Gürer
- Laboratory for Characterization and Processing of Polymers (LCPP), Faculty of Mechanical Engineering, University of Maribor, Smetanova ulica 17, SI - 2000 Maribor, Slovenia
| | - Tamilselvan Mohan
- Laboratory for Characterization and Processing of Polymers (LCPP), Faculty of Mechanical Engineering, University of Maribor, Smetanova ulica 17, SI - 2000 Maribor, Slovenia; Institute for Chemistry and Technology of Biobased System, Graz University of Technology, Stremayrgasse 9, 8010 Graz, Austria
| | - Matej Bračič
- Laboratory for Characterization and Processing of Polymers (LCPP), Faculty of Mechanical Engineering, University of Maribor, Smetanova ulica 17, SI - 2000 Maribor, Slovenia
| | - Ariana Barlič
- Educell, Podjetje Za Celično Biologijo, d.o.o. Prevale 9, 1236 Trzin, Slovenia
| | - Damjan Makuc
- Slovenian NMR Centre, National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia; EN-FIST Centre of Excellence, Trg Osvobodilne fronte 13, 1000 Ljubljana, Slovenia
| | - Janez Plavec
- Slovenian NMR Centre, National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia; EN-FIST Centre of Excellence, Trg Osvobodilne fronte 13, 1000 Ljubljana, Slovenia; Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, SI-1000 Ljubljana, Slovenia
| | - Karin Stana Kleinschek
- Institute for Chemistry and Technology of Biobased System, Graz University of Technology, Stremayrgasse 9, 8010 Graz, Austria.
| | - Rupert Kargl
- Laboratory for Characterization and Processing of Polymers (LCPP), Faculty of Mechanical Engineering, University of Maribor, Smetanova ulica 17, SI - 2000 Maribor, Slovenia; Institute for Chemistry and Technology of Biobased System, Graz University of Technology, Stremayrgasse 9, 8010 Graz, Austria.
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Yan S, Regenstein JM, Qi B, Li Y. Construction of protein-, polysaccharide- and polyphenol-based conjugates as delivery systems. Crit Rev Food Sci Nutr 2023:1-19. [PMID: 38108638 DOI: 10.1080/10408398.2023.2293253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2023]
Abstract
Natural polymers, such as polysaccharides and proteins, have been used to prepare several delivery systems owing to their abundance, bioactivity, and biodegradability. They are usually modified or combined with small molecules to form the delivery systems needed to meet different needs in food systems. This paper reviews the interactions of proteins, polysaccharides, and polyphenols in the bulk phase and discusses the design strategies, coupling techniques, and their applications as conjugates in emulsion delivery systems, including traditional, Pickering, multilayer, and high internal-phase emulsions. Furthermore, it explores the prospects of the application of conjugates in food preservation, food development, and nanocarrier development. Currently, there are seven methods for composite delivery systems including the Maillard reaction, carbodiimide cross-linking, alkali treatment, enzymatic cross-linking, free radical induction, genipin cross-linking, and Schiff base chemical cross-linking to prepare binary and ternary conjugates of proteins, polysaccharides, and polyphenols. To design an effective target complex and its delivery system, it is helpful to understand the physicochemical properties of these biomolecules and their interactions in the bulk phase. This review summarizes the knowledge on the interaction of biological complexes in the bulk phase, preparation methods, and the preparation of stable emulsion delivery system.
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Affiliation(s)
- Shizhang Yan
- College of Food Science, Northeast Agricultural University, Harbin, China
| | | | - Baokun Qi
- College of Food Science, Northeast Agricultural University, Harbin, China
| | - Yang Li
- College of Food Science, Northeast Agricultural University, Harbin, China
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Blinov A, Gvozdenko A, Golik A, Siddiqui SA, Göğüş F, Blinova A, Maglakelidze D, Shevchenko I, Rebezov M, Nagdalian A. Effect of Mn xO y Nanoparticles Stabilized with Methionine on Germination of Barley Seeds ( Hordeum vulgare L.). NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:nano13091577. [PMID: 37177122 PMCID: PMC10180524 DOI: 10.3390/nano13091577] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 04/28/2023] [Accepted: 05/05/2023] [Indexed: 05/15/2023]
Abstract
The aim of this research was to study the effect of MnxOy nanoparticles stabilized with L-methionine on the morphofunctional characteristics of the barley (Hordeum vulgare L.) crop. MnxOy nanoparticles stabilized with L-methionine were synthesized using potassium permanganate and L-methionine. We established that MnxOy nanoparticles have a diameter of 15 to 30 nm. According to quantum chemical modeling and IR spectroscopy, it is shown that the interaction of MnxOy nanoparticles with L-methionine occurs through the amino group. It is found that MnxOy nanoparticles stabilized with L-methionine have positive effects on the roots and seedling length, as well as the seed germination energy. The effect of MnxOy nanoparticles on Hordeum vulgare L. seeds is nonlinear. At a concentration of 0.05 mg/mL, there was a statistically significant increase in the length of seedlings by 68% compared to the control group. We found that the root lengths of samples treated with MnxOy nanoparticle sols with a concentration of 0.05 mg/mL were 62.8%, 32.7%, and 158.9% higher compared to samples treated with L-methionine, KMnO4, and the control sample, respectively. We have shown that at a concentration of 0.05 mg/mL, the germination energy of seeds increases by 50.0% compared to the control sample, by 10.0% compared to the samples treated with L-methionine, and by 13.8% compared to the samples treated with KMnO4.
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Affiliation(s)
- Andrey Blinov
- Department of Physics and Technology of Nanostructures and Materials, Physical and Technical Faculty, North Caucasus Federal University, 355017 Stavropol, Russia
| | - Alexey Gvozdenko
- Department of Physics and Technology of Nanostructures and Materials, Physical and Technical Faculty, North Caucasus Federal University, 355017 Stavropol, Russia
| | - Alexey Golik
- Department of Physics and Technology of Nanostructures and Materials, Physical and Technical Faculty, North Caucasus Federal University, 355017 Stavropol, Russia
| | - Shahida A Siddiqui
- Department of Biotechnology and Sustainability, Technical University of Munich (TUM), 94315 Straubing, Germany
- German Institute of Food Technologies (DIL e.V.), 49610 D-Quakenbrück, Germany
| | - Fahrettin Göğüş
- Department of Food Engineering, Engineering Faculty, University of Gaziantep, 27310 Gaziantep, Turkey
| | - Anastasiya Blinova
- Department of Physics and Technology of Nanostructures and Materials, Physical and Technical Faculty, North Caucasus Federal University, 355017 Stavropol, Russia
| | - David Maglakelidze
- Department of Physics and Technology of Nanostructures and Materials, Physical and Technical Faculty, North Caucasus Federal University, 355017 Stavropol, Russia
| | - Irina Shevchenko
- Department of Physics and Technology of Nanostructures and Materials, Physical and Technical Faculty, North Caucasus Federal University, 355017 Stavropol, Russia
| | - Maksim Rebezov
- Biophotonics Center, Prokhorov General Physics Institute of the Russian Academy of Science, 119991 Moscow, Russia
- Department of Scientific Research, V. M. Gorbatov Federal Research Center for Food Systems, 109240 Moscow, Russia
| | - Andrey Nagdalian
- Laboratory of Food and Industrial Biotechnology, Faculty of Food Engineering and Biotechnology, North Caucasus Federal University, 355017 Stavropol, Russia
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3D Printed Porous Nanocellulose-Based Scaffolds As Carriers for Immobilization of Glycosyltransferases. ACS APPLIED BIO MATERIALS 2022; 5:5728-5740. [PMID: 36469033 PMCID: PMC9768809 DOI: 10.1021/acsabm.2c00763] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Biocatalysis is increasingly becoming an alternative method for the synthesis of industrially relevant complex molecules. This can be realized by using enzyme immobilized polysaccharide-based 3D scaffolds as compatible carriers, with defined properties. Especially, immobilization of either single or multiple enzymes on a 3D printed polysaccharide scaffold, exhibiting well-organized interconnected porous structure and morphology, is a versatile approach to access the performance of industrially important enzymes. Here, we demonstrated the use of nanocellulose-based 3D porous scaffolds for the immobilization of glycosyltransferases, responsible for glycosylation in natural biosynthesis. The scaffolds were produced using an ink containing nanofibrillated cellulose (NFC), carboxymethyl cellulose (CMC), and citric acid. Direct-ink-writing 3D printing followed by freeze-drying and dehydrothermal treatment at elevated temperature resulted in chemically cross-linked scaffolds, featuring tunable negative charges (2.2-5.0 mmol/g), pore sizes (10-800 μm), fluid uptake capacity, and exceptional dimensional and mechanical stability in the wet state. The negatively charged scaffolds were applied to immobilize two sugar nucleotide-dependent glycosyltransferases (C-glycosyltransferase, Zbasic2-CGT; sucrose synthase, Zbasic2-SuSy), each harboring a cationic binding module (Zbasic2) to promote charge-based enzyme adsorption. Both enzymes were immobilized at ∼30 mg of protein/g of dry carrier (∼20% yield), independent of the scaffold used. Their specific activities were 0.50 U/mg (Zbasic2-CGT) and 0.19 U/mg (Zbasic2-SuSy), corresponding to an efficacy of 37 and 18%, respectively, compared to the soluble enzymes. The glycosyltransferases were coimmobilized and shown to be active in a cascade reaction to give the natural C-glycoside nothofagin from phloretin (1.0 mM; ∼95% conversion). All enzyme bound scaffolds showed reusability of a maximum of 5 consecutive reactions. These results suggest that the 3D printed and cross-linked NFC/CMC-based scaffolds could present a class of solid carriers for enzyme (co)-immobilization, with promising applications in glycosyltransferase-catalyzed synthesis and other fields of biocatalysis.
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Hrapovic S, Martinez-Farina CF, Sui J, Lavertu JD, Hemraz UD. Design of chitosan nanocrystals decorated with amino acids and peptides. Carbohydr Polym 2022; 298:120108. [DOI: 10.1016/j.carbpol.2022.120108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 09/06/2022] [Accepted: 09/09/2022] [Indexed: 11/02/2022]
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Organic acid cross-linked 3D printed cellulose nanocomposite bioscaffolds with controlled porosity, mechanical strength, and biocompatibility. iScience 2022; 25:104263. [PMID: 35521531 PMCID: PMC9062678 DOI: 10.1016/j.isci.2022.104263] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Revised: 01/24/2022] [Accepted: 04/12/2022] [Indexed: 11/24/2022] Open
Abstract
Herein, we fabricated chemically cross-linked polysaccharide-based three-dimensional (3D) porous scaffolds using an ink composed of nanofibrillated cellulose, carboxymethyl cellulose, and citric acid (CA), featuring strong shear thinning behavior and adequate printability. Scaffolds were produced by combining direct-ink-writing 3D printing, freeze-drying, and dehydrothermal heat-assisted cross-linking techniques. The last step induces a reaction of CA. Degree of cross-linking was controlled by varying the CA concentration (2.5–10.0 wt.%) to tune the structure, swelling, degradation, and surface properties (pores: 100-450 μm, porosity: 86%) of the scaffolds in the dry and hydrated states. Compressive strength, elastic modulus, and shape recovery of the cross-linked scaffolds increased significantly with increasing cross-linker concentration. Cross-linked scaffolds promoted clustered cell adhesion and showed no cytotoxic effects as determined by the viability assay and live/dead staining with human osteoblast cells. The proposed method can be extended to all polysaccharide-based materials to develop cell-friendly scaffolds suitable for tissue engineering applications. Chemically cross-linked polysaccharide-based 3D porous scaffolds were fabricated Physicochemical and mechanical properties increased with cross-linker concentration Lower cross-linker concentration led to higher porosity and interconnected pores Scaffolds promoted clustered cell adhesion and showed no cytotoxic effects
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Mohan T, Kleinschek KS, Kargl R. Polysaccharide peptide conjugates: Chemistry, properties and applications. Carbohydr Polym 2022; 280:118875. [PMID: 35027118 DOI: 10.1016/j.carbpol.2021.118875] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2021] [Revised: 10/25/2021] [Accepted: 11/05/2021] [Indexed: 11/02/2022]
Abstract
The intention of this publication is to give an overview on research related to conjugates of polysaccharides and peptides. Dextran, chitosan, and alginate were selected, to cover four of the most often encountered functional groups known to be present in polysaccharides. These groups are the hydroxyl, the amine, the carboxyl, and the acetal functionality. A collection of the commonly used chemical reactions for conjugation is provided. Conjugation results into distinct properties compared to the parent polysaccharide, and a number of these characteristics are highlighted. This review aims at demonstrating the applicability of said conjugates with a strong emphasis on biomedical applications, drug delivery, biosensing, and tissue engineering. Some suggestions are made for more rigorous chemistries and analytics that could be investigated. Finally, an outlook is given into which direction the field could be developed further. We hope that this survey provides the reader with a comprehensive summary and contributes to the progress of works that aim at synthetically combining two of the main building blocks of life into supramolecular structures with unprecedented biological response.
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Affiliation(s)
- Tamilselvan Mohan
- Institute for Chemistry and Technology of Biobased Systems (IBIOSYS), Graz University of Technology, Stremayrgasse 9, 8010 Graz, Austria
| | - Karin Stana Kleinschek
- Institute for Chemistry and Technology of Biobased Systems (IBIOSYS), Graz University of Technology, Stremayrgasse 9, 8010 Graz, Austria
| | - Rupert Kargl
- Institute for Chemistry and Technology of Biobased Systems (IBIOSYS), Graz University of Technology, Stremayrgasse 9, 8010 Graz, Austria; Institute for Automation, Faculty of Electrical Engineering and Computer Science, University of Maribor, Smetanova ulica 17, 2000 Maribor, Slovenia.
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Zhou Y, Edgar KJ. Regioselective synthesis of polysaccharide-amino acid ester conjugates. Carbohydr Polym 2022; 277:118886. [PMID: 34893289 DOI: 10.1016/j.carbpol.2021.118886] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 11/02/2021] [Accepted: 11/09/2021] [Indexed: 11/02/2022]
Abstract
Site-specific conjugation of polysaccharides with proteins is very challenging. Creating the ability to control chemo- and regioselective reaction between polysaccharides and amino acid derivatives can not only create potentially useful and bioactive natural polymer constructs, but should also provide useful guidance for the principles of polysaccharide-protein conjugate synthesis. In this work, we exploited regioselective bromination of the non-reducing end primary dextran hydroxyl using N-bromosuccinimide (NBS) and triphenylphosphine (Ph3P) in the dimethylacetamide (DMAc) and lithium bromide solvent system, thereby enabling a regio- and chemoselective synthetic strategic approach to a variety of polysaccharide-amino acid ester adducts. We demonstrated selective condensation of the α-amino groups of esters of the amino acids tyrosine and proline, displacing the single, terminal C6 bromides of 6-BrDextran, as well as the 6-Br moieties of 6-BrCA320S, with high conversion (71-96%). Histidine ester side group amines were found to react with 6-BrCA320S, while those of tryptophan ester did not. These results provide useful access to polysaccharide-amino acid ester adducts of various architectures, and guide us in designing new pathways to polysaccharide-protein copolymers.
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Affiliation(s)
- Yang Zhou
- Department of Sustainable Biomaterials, Virginia Tech, Blacksburg, VA 24061, United States
| | - Kevin J Edgar
- Department of Sustainable Biomaterials, Virginia Tech, Blacksburg, VA 24061, United States; Macromolecules Innovation Institute, Virginia Tech, Blacksburg, VA 24061, United States.
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