Polysaccharides: Structure, Properties, and Applications

A special issue of Polymers (ISSN 2073-4360). This special issue belongs to the section "Biomacromolecules, Biobased and Biodegradable Polymers".

Deadline for manuscript submissions: closed (30 September 2022) | Viewed by 38774

Special Issue Editors


E-Mail Website
Guest Editor
Department of Carbohydrates and Cereals, University of Chemistry and Technology, Prague, 166 28 Praha 6, Czech Republic
Interests: polysaccharides; spectroscopic methods; food composition; chemical modification

E-Mail Website
Co-Guest Editor
Department of Carbohydrates and Cereals, University of Chemistry and Technology, Prague, Czech Republic
Interests: polysaccharides; chromatography; chocolate; confectionery
Special Issues, Collections and Topics in MDPI journals

E-Mail Website
Co-Guest Editor
Department of Carbohydrates and Cereals, University of Chemistry and Technology, Prague, Czech Republic
Interests: starch; chemical modification; composite materials; nanoparticles; extrusion

Special Issue Information

Dear Colleagues,

Polysaccharides are biological polymers that are widely distributed in nature. In various living organisms, they usually play the role of structural components or energy stores, but some of them can perform various specific functions. Despite the fact that polysaccharides have been well known to people for centuries, many modern studies are devoted to the isolation and characterization of new and unusual polysaccharides that exhibit specific properties and, thus, can be used in various industries, including the food, cosmetic, medicine, and pharmaceutical industries.

This Special Issue will focus on various aspects of natural polysaccharides, including their isolation from raw materials, purification, structure and composition, molecular weight and size, physical properties, and applications. Authors may report on polysaccharide studies using advanced preparative and analytical approaches, including modern separation and spectroscopic methods, and characterize them as hydrocolloids or components of novel materials for various applications.

The 16th International Conference on Polysaccharides–Glycoscience (16 ICPG) will take place in Prague from 4 to 6 November 2020 (https://www.polysaccharides.csch.cz/). The conference will be focused on the industrial production and use of polysaccharides and the abundance, properties, and structure of biologically active natural and modified polysaccharides. The main topics are: (i) characterization and analysis of natural polysaccharides; (ii) physiological effects of natural polysaccharides; (iii) production of polysaccharides and agricultural sources; (iv) biodegradable plastics based on polysaccharides; (v) chemically modified polysaccharides; (vi) resistant and slowly digestible starch; and (vii) polysaccharide nanoparticles. The deadline for abstracts is 15 July 2020, and the deadline for full texts is 30 August 2020. Alternatively, it may be possible to publish an advanced contribution to 16 ICPG as a research paper in this Special Issue.

Dr. Andriy Synytsya
Prof. Dr. Jana Copikova
Dr. Evzen Sarka
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Polymers is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2700 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • polysaccharides
  • isolation
  • composition
  • structure
  • molecular mass
  • physical properties
  • hydrocolloids
  • chemical modification
  • materials

Published Papers (12 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

Jump to: Review

13 pages, 2233 KiB  
Article
Study of Dynamic Accumulation in β-D-Glucan in Oat (Avena sativa L.) during Plant Development
by Peter Hozlár, Veronika Gregusová, Peter Nemeček, Svetlana Šliková and Michaela Havrlentová
Polymers 2022, 14(13), 2668; https://0-doi-org.brum.beds.ac.uk/10.3390/polym14132668 - 30 Jun 2022
Cited by 3 | Viewed by 1397
Abstract
Oat is an important natural source of β-D-glucan. This polysaccharide of the cell wall of selected cereals is known for a number of health-promoting effects, such as reducing the level of cholesterol in the blood serum, stabilizing the level of blood glucose, or [...] Read more.
Oat is an important natural source of β-D-glucan. This polysaccharide of the cell wall of selected cereals is known for a number of health-promoting effects, such as reducing the level of cholesterol in the blood serum, stabilizing the level of blood glucose, or enhancing immunity. β-D-glucan has positive effects in the plant itself. There is a lack of information available, but the storage capacity of the polysaccharide and its importance as a protective substance in the plant during mild forms of biotic and abiotic stress are described. The accumulation of β-D-glucan during the ontogenetic development of oats (Avena sativa L.) was determined in the present work. Two naked (Valentin, Vaclav) and two hulled (Hronec, Tatran) oat varieties were used. Samples of each plant (root, stem, leaf, panicle) were collected in four stages of the plant’s development (BBCH 13, 30, 55, 71). The average content of the biopolymer was 0.29 ± 0.14% in roots, 0.32 ± 0.11% in stems, 0.48 ± 0.13% in leaves and 1.28 ± 0.79% in panicles, respectively. For root and panicle, in both hulled and naked oat varieties, sampling date was the factor of variability in the content of β-D-glucan. In stems in hulled varieties and leaves in naked varieties, neither the sampling date nor variety influenced the polysaccharide content. The content of β-D-glucan in the leaves of hulled and naked varieties decreased during the first three stages of plant development, but in the stage of milk ripeness the amount increased. The decreasing trend during milk ripeness, was also observed in the roots of both hulled and naked oats. However, in the panicle of hulled and naked oat varieties, the content of β-D-glucan increased during plant growth. Due to practical applications of natural resources of β-D-glucan and isolated β-D-glucan is useful to know the factors influencing its content as well as to ascertain the behavior of the polysaccharide during plant development. Full article
(This article belongs to the Special Issue Polysaccharides: Structure, Properties, and Applications)
Show Figures

Figure 1

16 pages, 1938 KiB  
Article
Characterization, Antioxidant Activities, and Functional Properties of Mucilage Extracted from Corchorus olitorius L.
by Songmin Oh and Do-Yeong Kim
Polymers 2022, 14(12), 2488; https://0-doi-org.brum.beds.ac.uk/10.3390/polym14122488 - 18 Jun 2022
Cited by 10 | Viewed by 4775
Abstract
This study extracted the mucilage from Corchorus olitorius L. to observe its chemical and functional properties and suggest its possible applications in various fields. Corchorus olitorius L. mucilage was isolated by hot water extraction. FT-IR and HPAEC-PAD were used to describe the chemical [...] Read more.
This study extracted the mucilage from Corchorus olitorius L. to observe its chemical and functional properties and suggest its possible applications in various fields. Corchorus olitorius L. mucilage was isolated by hot water extraction. FT-IR and HPAEC-PAD were used to describe the chemical composition, and the functional properties and antioxidant activities of the mucilage were also examined. The mucilage was mainly composed of uronic acid (34.24%, w/w). The solubility was 79.48 ± 1.08% at 65 °C, the swelling index was 29.01 ± 2.54% at 25 °C, and the water-holding capacity and oil-binding capacity were 28.66 ± 1.48 and 8.423 ± 0.23 g/g, respectively. The mucilage viscosity increased from 4.38 to 154.97 cP in a concentration-dependent manner. Increasing the concentration decreased the emulsion activity and increased the emulsion stability, most likely because of the corresponding increase in surface tension and viscosity. Results from antioxidant assays confirmed that the in-vitro radical scavenging activity of the mucilage increased with concentration. This study shows that C. olitorius L. can be utilized as a new hydrocolloid source, with potential applications in fields ranging from foods to cosmetics and pharmaceuticals. Full article
(This article belongs to the Special Issue Polysaccharides: Structure, Properties, and Applications)
Show Figures

Figure 1

21 pages, 2067 KiB  
Article
Chemical Composition and Rheological Properties of Seed Mucilages of Various Yellow- and Brown-Seeded Flax (Linum usitatissimum L.) Cultivars
by Yana Troshchynska, Roman Bleha, Andriy Synytsya and Jiří Štětina
Polymers 2022, 14(10), 2040; https://0-doi-org.brum.beds.ac.uk/10.3390/polym14102040 - 17 May 2022
Cited by 7 | Viewed by 2382
Abstract
When seeds sown in the soil become wet, their hulls secrete viscous matter that can retain water and thus support germination. Flaxseed mucilage (FSM) is an example of such a material and is attractive for food, cosmetic, and pharmaceutical applications due to its [...] Read more.
When seeds sown in the soil become wet, their hulls secrete viscous matter that can retain water and thus support germination. Flaxseed mucilage (FSM) is an example of such a material and is attractive for food, cosmetic, and pharmaceutical applications due to its suitable rheological properties. FSM consists mainly of two polysaccharides, namely, arabinoxylan and rhamnogalacturonan I, and it also contains some proteins, minerals, and phenolic compounds. The genotype and the year of the flax harvest can significantly affect the composition and functional properties of FSM. In this work, FSM samples were isolated from flax seeds of different cultivars and harvest years, and their structural and rheological properties were compared using statistical methods. The samples showed significant variability in composition and rheological properties depending on the cultivar and storage time. It was found that the ratio of two polysaccharide fractions and the contribution of less-prevalent proteins are important factors determining the rheological parameters of FSM, characterizing the shear-thinning, thixotropic, and dynamic viscoelastic behavior of this material in aqueous solutions. The yield strength and the hysteresis loop were found to be associated with the contribution of the pectin fraction, which included homogalacturonan and rhamnogalacturonan I. In contrast, the shear-thinning and especially the dynamic viscoelastic properties depended on the arabinoxylan content. Proteins also affected the viscoelastic properties and maintained the elastic component of FSM in the solution. The above structural and rheological characteristics should be taken into account when considering effective applications for this material. Full article
(This article belongs to the Special Issue Polysaccharides: Structure, Properties, and Applications)
Show Figures

Figure 1

18 pages, 4597 KiB  
Article
Polysaccharides from Basidiocarps of the Polypore Fungus Ganoderma resinaceum: Isolation and Structure
by Roman Bleha, Lucie Třešnáková, Leonid Sushytskyi, Peter Capek, Jana Čopíková, Pavel Klouček, Ivan Jablonský and Andriy Synytsya
Polymers 2022, 14(2), 255; https://0-doi-org.brum.beds.ac.uk/10.3390/polym14020255 - 08 Jan 2022
Cited by 16 | Viewed by 2706
Abstract
In this study, we focused on the isolation and structural characterization of polysaccharides from a basidiocarp of polypore fungus Ganoderma resinaceum. Polysaccharide fractions were obtained by successive extractions with cold water at room temperature (20 °C), hot water under reflux (100 °C), [...] Read more.
In this study, we focused on the isolation and structural characterization of polysaccharides from a basidiocarp of polypore fungus Ganoderma resinaceum. Polysaccharide fractions were obtained by successive extractions with cold water at room temperature (20 °C), hot water under reflux (100 °C), and a solution of 1 mol L−1 sodium hydroxide. The purity of all fractions was controlled mainly by Fourier transform infrared (FTIR) spectroscopy, and their composition and structure were characterized by organic elemental analysis; neutral sugar and methylation analyses by gas chromatography equipped with flame ionization detector (GC/FID) and mass spectrometry detector (GC/MS), respectively; and by correlation nuclear magnetic resonance (NMR) spectroscopy. The aqueous extracts contained two main polysaccharides identified as a branched O-2-β-d-mannosyl-(1→6)-α-d-galactan and a highly branched (1→3)(1→4)(1→6)-β-d-glucan. Mannogalactan predominated in the cold water extract, and β-d-glucan was the main product of the hot water extract. The hot water soluble fraction was further separated by preparative anion exchange chromatography into three sub-fractions; two of them were identified as branched β-d-glucans with a structure similar to the corresponding polysaccharide of the original fraction. The alkaline extract contained a linear (1→3)-α-d-glucan and a weakly branched (1→3)-β-d-glucan having terminal β-d-glucosyl residues attached to O-6 of the backbone. The insoluble part after all extractions was identified as a polysaccharide complex containing chitin and β-d-glucans. Full article
(This article belongs to the Special Issue Polysaccharides: Structure, Properties, and Applications)
Show Figures

Graphical abstract

17 pages, 3430 KiB  
Communication
Screening of the Chemical Composition and Identification of Hyaluronic Acid in Food Supplements by Fractionation and Fourier-Transform Infrared Spectroscopy
by Tamilla Mirzayeva, Jana Čopíková, František Kvasnička, Roman Bleha and Andriy Synytsya
Polymers 2021, 13(22), 4002; https://0-doi-org.brum.beds.ac.uk/10.3390/polym13224002 - 19 Nov 2021
Cited by 9 | Viewed by 2518
Abstract
Hyaluronic acid, together with collagen, vitamins or plant extracts, is a part of many cosmetic and food preparations. For example, this polysaccharide is used in formulation of many food supplements due to its protective effects on human health. In this work, the screening [...] Read more.
Hyaluronic acid, together with collagen, vitamins or plant extracts, is a part of many cosmetic and food preparations. For example, this polysaccharide is used in formulation of many food supplements due to its protective effects on human health. In this work, the screening of the chemical composition of three chosen dietary supplements (powder, tablets and capsules) containing hyaluronic acid was carried out using Fourier-transform infrared spectroscopy. Because of the low amount of analyte in all these samples, it was isolated or concentrated prior to the analysis using a suitable sequential fractionation protocol. Individual isolation procedures were established for each sample based on their declared composition. Firstly, the major components such as collagen or vitamins were removed to obtain polysaccharide fractions by the enzymatic treatment and/or washing out with the appropriate solvents. In some cases, the water insoluble part was removed from the rest dissolved in water. Then, hyaluronic acid was precipitated with copper(II) cations and thus separated from the other polysaccharides. Finally, the analyte was identified in the enriched fractions by the characteristic vibrational bands. The amount of hyaluronic acid in the purified fractions was determined in three ways: gravimetrically, spectrophotometrically, and using isotachophoresis. The combination of the appropriate preparative and analytical steps led to the successful evaluation of chemical composition, finding and quantification of hyaluronic acid in all the studied samples. Full article
(This article belongs to the Special Issue Polysaccharides: Structure, Properties, and Applications)
Show Figures

Figure 1

10 pages, 2472 KiB  
Article
Dietary Polysaccharide from Enteromorpha clathrata Attenuates Obesity and Increases the Intestinal Abundance of Butyrate-Producing Bacterium, Eubacterium xylanophilum, in Mice Fed a High-Fat Diet
by Jiali Wei, Yiran Zhao, Chen Zhou, Qing Zhao, Hongqian Zhong, Xinyu Zhu, Tianyu Fu, Lin Pan, Qingsen Shang and Guangli Yu
Polymers 2021, 13(19), 3286; https://0-doi-org.brum.beds.ac.uk/10.3390/polym13193286 - 26 Sep 2021
Cited by 31 | Viewed by 2425
Abstract
Previous studies have suggested that polysaccharide from Enteromorpha clathrata (ECP) could be used as a potential prebiotic to treat dysbiosis-associated diseases. However, whether it has any therapeutic effects on obesity has not been investigated. In the present study, we explored the anti-obesity effect [...] Read more.
Previous studies have suggested that polysaccharide from Enteromorpha clathrata (ECP) could be used as a potential prebiotic to treat dysbiosis-associated diseases. However, whether it has any therapeutic effects on obesity has not been investigated. In the present study, we explored the anti-obesity effect of ECP and illustrated that it can significantly reduce the body weight and decrease the serum levels of triacylglycerol and cholesterol in high-fat diet (HFD)-fed mice. As revealed by 16S rRNA high-throughput sequencing and bioinformatic analysis, HFD remarkably changed the composition of the gut microbiota and promoted the growth of opportunistic pathogens such as Mucispirillum, Desulfobacterota and Alphaproteobacteria in obese mice. Interestingly, ECP improved intestinal dysbiosis caused by HFD and reshaped the structure of the gut microbiota in diseased mice by increasing the abundance of butyrate-producing bacterium, Eubacterium xylanophilum, in the gut. Altogether, we demonstrate for the first time an anti-obesity effect of ECP and shed new light into its therapeutic mechanisms from the perspective of gut microbiota. Our study will pave the way for the development of ECP as new prebiotic for the treatment of obesity and its associated disorders. Full article
(This article belongs to the Special Issue Polysaccharides: Structure, Properties, and Applications)
Show Figures

Figure 1

11 pages, 617 KiB  
Article
Phosphorylation of Maize Starch Enhanced with High-Voltage Electrical Discharge (HVED) Instead of Thermal Treatment
by Artur Gryszkin, Marijana Grec, Đurđica Ačkar, Tomasz Zięba, Antun Jozinović, Drago Šubarić, Borislav Miličević, Marijana Blažić and Jurislav Babić
Polymers 2021, 13(19), 3231; https://0-doi-org.brum.beds.ac.uk/10.3390/polym13193231 - 23 Sep 2021
Cited by 1 | Viewed by 1704
Abstract
The aim of this research was to explore the use of a high-voltage electrical treatment (HVED) as a substitute for heating during the phosphorylation of maize starch. Starch was treated with HVED, phosphorylated with Na2HPO4 or Na5P3 [...] Read more.
The aim of this research was to explore the use of a high-voltage electrical treatment (HVED) as a substitute for heating during the phosphorylation of maize starch. Starch was treated with HVED, phosphorylated with Na2HPO4 or Na5P3O10 with and without thermal treatment and phosphorylated in combination with HVED prior to and after the chemical modification. When starch was phosphorylated with Na2HPO4, HVED was more efficient in catalyzing reaction (3.89 mg P/kg for 30 min HVED in relation to 0.43 mg P/kg for thermal treatment), whereas with Na5P3O10 similar P content was achieved as with thermal treatment (0.76 P/kg for 30 min HVED in relation to 0.86 mg P/kg). The order of HVED and chemical reactions did not have a marked effect on phosphorous content. In combination with Na2HPO4, HVED pre-treatment had a more pronounced effect on the solubility and water absorption, whereas post-treatment was favoured with Na5P3O10. Mean diameter was increased by all treatments, where HVED had a marked effect. Enthalpy of gelatinization ranged from 11.76 J/g for starch treated with Na5P3O10 and 10 min-HVED to 13.58 J/g for Na5P3O10 treated sample. G′ and G″ increased after both thermally and HVED enhanced phosphorylations, with a slightly more pronounced effect of the HVED. Full article
(This article belongs to the Special Issue Polysaccharides: Structure, Properties, and Applications)
Show Figures

Graphical abstract

19 pages, 2384 KiB  
Article
Hyaluronan and Derivatives: An In Vitro Multilevel Assessment of Their Potential in Viscosupplementation
by Annalisa La Gatta, Antonietta Stellavato, Valentina Vassallo, Celeste Di Meo, Giuseppe Toro, Giovanni Iolascon and Chiara Schiraldi
Polymers 2021, 13(19), 3208; https://0-doi-org.brum.beds.ac.uk/10.3390/polym13193208 - 22 Sep 2021
Cited by 6 | Viewed by 2191
Abstract
In this research work, viscosupplements based on linear, derivatized, crosslinked and complexed HA forms were extensively examined, providing data on the hydrodynamic parameters for the water-soluble-HA-fraction, rheology, sensitivity to enzymatic hydrolysis and capacity to modulate specific biomarkers’ expression in human pathological chondrocytes and [...] Read more.
In this research work, viscosupplements based on linear, derivatized, crosslinked and complexed HA forms were extensively examined, providing data on the hydrodynamic parameters for the water-soluble-HA-fraction, rheology, sensitivity to enzymatic hydrolysis and capacity to modulate specific biomarkers’ expression in human pathological chondrocytes and synoviocytes. Soluble HA ranged from 0 to 32 mg/mL and from 150 to 1330 kDa MW. The rheological behavior spanned from purely elastic to viscoelastic, suggesting the diversity of the categories that are suitable for restoring specific/different features of the healthy synovial fluid. The rheological parameters were reduced in a diverse manner upon dilution and hyaluronidases action, indicating different durations of the viscosupplementation effect. Bioactivity was found for all the samples, increasing the expression of different matrix markers (e.g., hyaluronan-synthase); however, the hybrid cooperative complexes performed better in most of the experiments. Hybrid cooperative complexes improved COLII mRNA expression (~12-fold increase vs. CTR), proved the most effective at preserving cell phenotype. In addition, in these models, the HA samples reduced inflammation. IL-6 was down-regulated vs. CTR by linear and chemically modified HA, and especially by hybrid complexes. The results represent the first comprehensive panel of data directly comparing the diverse HA forms for intra-articular injections and provide valuable information for tailoring products’ clinical use as well as for designing new, highly performing HA-formulations that can address specific needs. Full article
(This article belongs to the Special Issue Polysaccharides: Structure, Properties, and Applications)
Show Figures

Graphical abstract

12 pages, 2293 KiB  
Article
Structure and Properties of Octenyl Succinic Anhydride-Modified High-Amylose Japonica Rice Starches
by Wei Zhang, Bei Cheng, Jiahui Li, Zaixi Shu, Pingping Wang and Xuefeng Zeng
Polymers 2021, 13(8), 1325; https://0-doi-org.brum.beds.ac.uk/10.3390/polym13081325 - 18 Apr 2021
Cited by 22 | Viewed by 2952
Abstract
Starches rich in amylose are promising functional ingredients for calory-reduced foods. In this research, a high-amylose Japonica rice starch (amylose content 33.3%) was esterified with octenyl succinic anhydride (OSA) to improve the functional properties. The OSA-modified derivatives were evaluated for structure and functional [...] Read more.
Starches rich in amylose are promising functional ingredients for calory-reduced foods. In this research, a high-amylose Japonica rice starch (amylose content 33.3%) was esterified with octenyl succinic anhydride (OSA) to improve the functional properties. The OSA-modified derivatives were evaluated for structure and functional properties, with OSA-modified normal Japonica rice starch (amylose content 18.8%) used as control. Fourier transform infrared spectra confirmed the introduction of OSA groups to starch. OSA modification made little change to morphology and particle size of high-amylose starch, but decreased the relative crystallinity and pasting temperature and increased the pasting viscosity, swelling power, emulsifying stability, and resistant starch (RS) content. The changes of properties were related to the degree of substitution (DS). Typically, OSA-modified high-amylose starch at DS of 0.0285 shows polyhedral-shape granules, with a volume-average particle diameter of 8.87 μm, peak viscosity of 5730 cp, and RS content of 35.45%. OSA-modified high-amylose starch had greater peak viscosity and RS content and lower swelling power than OSA-modified normal starch of similar DS, but the two kinds of derivatives did not have a significant difference in emulsifying stability. The OSA-modified high-amylose Japonica rice starch could be used as an emulsifier, thickener, and fat replacer in food systems. Full article
(This article belongs to the Special Issue Polysaccharides: Structure, Properties, and Applications)
Show Figures

Graphical abstract

16 pages, 13115 KiB  
Article
Steady and Oscillatory Shear Flow Behavior of Different Polysaccharides with Laponite®
by Marcos Blanco-López, Álvaro González-Garcinuño, Antonio Tabernero and Eva M. Martín del Valle
Polymers 2021, 13(6), 966; https://0-doi-org.brum.beds.ac.uk/10.3390/polym13060966 - 22 Mar 2021
Cited by 5 | Viewed by 2076
Abstract
The rheological behavior, in terms of steady and oscillatory shear flow, of Laponite® with different polysaccharides (alginate, chitosan, xanthan gum and levan) in salt-free solutions was studied. Results showed that a higher polymer concentration increased the zero-rate viscosity and decreased the critical [...] Read more.
The rheological behavior, in terms of steady and oscillatory shear flow, of Laponite® with different polysaccharides (alginate, chitosan, xanthan gum and levan) in salt-free solutions was studied. Results showed that a higher polymer concentration increased the zero-rate viscosity and decreased the critical strain rate (Cross model fit) as well as increasing the elastic and viscous moduli. Those properties (zero-rate viscosity and critical strain rate) can be a suitable indicator of the effect of the Laponite® on the shear flow behavior for the different solutions. Specifically, the effect of the Laponite® predominates for solutions with large critical strain rate and low zero-rate viscosity, modifying significantly the previous parameters and even the yield stress (if existing). On the other hand, larger higher polymeric concentration hinders the formation of the platelet structure, and polymer entanglement becomes predominant. Furthermore, the addition of high concentrations of Laponite® increases the elastic nature, but without modifying the typical mechanical spectra for polymeric solutions. Finally, Laponite® was added to (previously crosslinked) gels of alginate and chitosan, obtaining different results depending on the material. These results highlight the possibility of predicting qualitatively the impact of the Laponite® on different polymeric solutions depending on the solutions properties. Full article
(This article belongs to the Special Issue Polysaccharides: Structure, Properties, and Applications)
Show Figures

Graphical abstract

Review

Jump to: Research

16 pages, 1333 KiB  
Review
Modified Starch-Based Adhesives: A Review
by Jidapa Watcharakitti, Ei Ei Win, Jaturavit Nimnuan and Siwaporn Meejoo Smith
Polymers 2022, 14(10), 2023; https://0-doi-org.brum.beds.ac.uk/10.3390/polym14102023 - 16 May 2022
Cited by 30 | Viewed by 8907
Abstract
Consumer trends towards environmentally friendly products are driving plastics industries to investigate more benign alternatives to petroleum-based polymers. In the case of adhesives, one possibility to achieve sustainable production is to use non-toxic, low-cost starches as biodegradable raw materials for adhesive production. While [...] Read more.
Consumer trends towards environmentally friendly products are driving plastics industries to investigate more benign alternatives to petroleum-based polymers. In the case of adhesives, one possibility to achieve sustainable production is to use non-toxic, low-cost starches as biodegradable raw materials for adhesive production. While native starch contains only hydroxyl groups and has limited scope, chemically modified starch shows superior water resistance properties for adhesive applications. Esterified starches, starches with ester substituents, can be feasibly produced and utilized to prepare bio-based adhesives with improved water resistance. Syntheses of esterified starch materials can involve esterification, transesterification, alkylation, acetylation, succinylation, or enzymatic reactions. The main focus of this review is on the production of esterified starches and their utilization in adhesive applications (for paper, plywood, wood composites, fiberboard, and particleboard). The latter part of this review discusses other processes (etherification, crosslinking, grafting, oxidation, or utilizing biobased coupling agents) to prepare modified starches that can be further applied in adhesive production. Further discussion on the characteristics of modified starch materials and required processing methods for adhesive production is also included. Full article
(This article belongs to the Special Issue Polysaccharides: Structure, Properties, and Applications)
Show Figures

Figure 1

21 pages, 40030 KiB  
Review
Bacterial Succinoglycans: Structure, Physical Properties, and Applications
by Jae-pil Jeong, Yohan Kim, Yiluo Hu and Seunho Jung
Polymers 2022, 14(2), 276; https://0-doi-org.brum.beds.ac.uk/10.3390/polym14020276 - 11 Jan 2022
Cited by 16 | Viewed by 3079
Abstract
Succinoglycan is a type of bacterial anionic exopolysaccharide produced from Rhizobium, Agrobacterium, and other soil bacteria. The exact structure of succinoglycan depends in part on the type of bacterial strain, and the final production yield also depends on the medium composition, [...] Read more.
Succinoglycan is a type of bacterial anionic exopolysaccharide produced from Rhizobium, Agrobacterium, and other soil bacteria. The exact structure of succinoglycan depends in part on the type of bacterial strain, and the final production yield also depends on the medium composition, culture conditions, and genotype of each strain. Various bacterial polysaccharides, such as cellulose, xanthan, gellan, and pullulan, that can be mass-produced for biotechnology are being actively studied. However, in the case of succinoglycan, a bacterial polysaccharide, relatively few reports on production strains or chemical and structural characteristics have been published. Physical properties of succinoglycan, a non-Newtonian and shear thinning fluid, have been reported according to the ratio of substituents (pyruvyl, succinyl, acetyl group), molecular weight (Mw), and measurement conditions (concentration, temperature, pH, metal ion, etc.). Due to its unique rheological properties, succinoglycan has been mainly used as a thickener and emulsifier in the cosmetic and food industries. However, in recent reports, succinoglycan and its derivatives have been used as functional biomaterials, e.g., in stimuli-responsive drug delivery systems, therapeutics, and cell culture scaffolds. This suggests a new and expanded application of succinoglycan as promising biomaterials in biomedical fields, such as tissue engineering, regenerative medicine, and pharmaceuticals using drug delivery. Full article
(This article belongs to the Special Issue Polysaccharides: Structure, Properties, and Applications)
Show Figures

Graphical abstract

Back to TopTop