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Special Issue "The Fascinating Story of Natural Polysaccharides in Glycosciences: From Extraction to Applications"

A special issue of Molecules (ISSN 1420-3049). This special issue belongs to the section "Natural Products Chemistry".

Deadline for manuscript submissions: 30 September 2019

Special Issue Editor

Guest Editor
Prof. Cédric Delattre

Université Clermont Auvergne, CNRS, SIGMA Clermont, Institut Pascal, F-63000 Clermont-Ferrand, France
Website | E-Mail
Interests: Biocatalyst, Biopolymers, Biochemistry of poly- et oligosaccharides, Biorefinery (plant, micro- and macro-algae, fungal), Green chemistry, Enzymology, Glycochemisty, biobased and bio-inspired Material

Special Issue Information

Dear Colleagues,

For a long time, natural biopolymers, such as polysaccharides, have fascinated humanity. Polysaccharides are certainly one of the greatest varied families of bio-polymers in terms of structure and use. Depending on the origin (animal, plant, algal or microbial), polysaccharides may be linear, substituted, or more or less branched. Polysaccharides are highly variable and complex biomolecules of which the inventory of structures is still partial, as nature still preserves many of the unexplored biotopes. In this context, many works from all over the world have led to the discovery of original polysaccharides extracted from medicinal plants and algae, or produced from bacteria and microalgae, with high potential as food ingredients or as biological assets. Their main roles in the organism are to either provide structural support as a constituent of a cell wall or to store energy in the cell. Some polysaccharides and/or their oligosaccharide derivatives may be involved in cellular and sub-cellular communication processes, as in the case of glycosaminoglycans (GAGs). Consequently, this Special Issue aims to (i) review and identify the main polysaccharides from all biotopes (plant, bacteria, animal and microalgae), from the past to the present, and (ii) identity the lastest bioactive polysaccharides and their techno-functional derivatives (low molecular weight, oligosaccharides, hydrogels, etc.) with advantageous effects in the agricultural, pharmaceutical and food fields.

Prof. Delattre Cedric
Guest Editor

Manuscript Submission Information

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Keywords

  • polysaccharides
  • extractions processes
  • pharmaceutical applications
  • agricultural applications
  • material

Published Papers (11 papers)

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Research

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Open AccessArticle
Antiviral Effects of Houttuynia cordata Polysaccharide Extract on Murine Norovirus-1 (MNV-1)—A Human Norovirus Surrogate
Molecules 2019, 24(9), 1835; https://doi.org/10.3390/molecules24091835
Received: 4 March 2019 / Revised: 7 May 2019 / Accepted: 9 May 2019 / Published: 13 May 2019
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Abstract
Houttuynia cordata is an herbal plant rich in polysaccharides and with several pharmacological activities. Human noroviruses (HuNoVs) are the most common cause of foodborne viral gastroenteritis throughout the world. In this study, H. cordata polysaccharide (HP), with a molecular weight of ~43 kDa, [...] Read more.
Houttuynia cordata is an herbal plant rich in polysaccharides and with several pharmacological activities. Human noroviruses (HuNoVs) are the most common cause of foodborne viral gastroenteritis throughout the world. In this study, H. cordata polysaccharide (HP), with a molecular weight of ~43 kDa, was purified from H. cordata water extract (HWE). The polysaccharide HP was composed predominantly of galacturonic acid, galactose, glucose, and xylose in a molar ratio of 1.56:1.49:1.26:1.11. Methylation and NMR analyses revealed that HP was a pectin-like acidic polysaccharide mainly consisting of α-1,4-linked GalpA, β-1,4-linked Galp, β-1,4-linked Glcp, and β-1,4-linked Xylp residues. To evaluate the antiviral activity of H. cordata extracts, we compared the anti-norovirus potential of HP with HWE and ethanol extract (HEE) from H. cordata by plaque assay (plaque forming units (PFU)/mL) for murine norovirus-1 (MNV-1), a surrogate of HuNoVs. Viruses at high (8.09 log10 PFU/mL) or low (4.38 log10 PFU/mL) counts were mixed with 100, 250, and 500 μg/mL of HP, HWE or HEE and incubated for 30 min at room temperature. H. cordata polysaccharide (HP) was more effective than HEE in reducing MNV-1 plaque formation, but less effective than HWE. When MNV-1 was treated with 500 μg/mL HP, the infectivity of MNV-1 decreased to an undetectable level. The selectivity indexes of each sample were 1.95 for HEE, 5.74 for HP, and 16.14 for HWE. The results of decimal reduction time and transmission electron microscopic revealed that HP has anti-viral effects by deforming and inflating virus particles, thereby inhibiting the penetration of viruses in target cells. These findings suggest that HP might have potential as an antiviral agent in the treatment of viral diseases. Full article
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Open AccessArticle
Effect of Chitosan Dispersion and Microparticles on Older Streptococcus mutans Biofilms
Molecules 2019, 24(9), 1808; https://doi.org/10.3390/molecules24091808
Received: 29 March 2019 / Revised: 7 May 2019 / Accepted: 9 May 2019 / Published: 10 May 2019
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Abstract
(1) Background: The effectiveness of chitosan to improve the action of antimicrobial compounds against planktonic bacteria and young biofilms has been widely investigated in Dentistry, where the biofilm lifecycle is a determining factor for the success of antibacterial treatment. In the present study, [...] Read more.
(1) Background: The effectiveness of chitosan to improve the action of antimicrobial compounds against planktonic bacteria and young biofilms has been widely investigated in Dentistry, where the biofilm lifecycle is a determining factor for the success of antibacterial treatment. In the present study, mature Streptococcus mutans biofilms were treated with chitosan dispersion (CD) or chitosan microparticles (CM). (2) Methods: CD at 0.25% and 1% were characterized by texture analysis, while CD at 2% was spray-dried to form CM, which were characterized with respect to particle size distribution, zeta potential, and morphology. After determining the minimum inhibitory and bactericidal concentrations, S. mutans biofilms were grown on glass slides exposed 8×/day to 10% sucrose and 2×/day to CD or CM at 0.25% and 1%. Biofilm viability and acidogenicity were determined, using appropriate control groups for each experiment. (3) Results: CD had high viscosity and CM were spherical, with narrow size distribution and positive zeta potential. CM affected bacterial viability and acidogenicity in mature S. mutans biofilms more strongly than CD, especially at 1%. (4) Conclusions: Both chitosan forms exerted antimicrobial effect against mature S. mutans biofilms. CM at 1% can reduce bacterial viability and acidogenicity more effectively than CD at 1%, and thereby be more effective to control the growth of mature biofilms in vitro. Full article
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Open AccessArticle
The Effect of Concentration on the Cross-Linking and Gelling of Sodium Carbonate-Soluble Apple Pectins
Molecules 2019, 24(8), 1635; https://doi.org/10.3390/molecules24081635
Received: 3 April 2019 / Revised: 20 April 2019 / Accepted: 22 April 2019 / Published: 25 April 2019
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Abstract
The cross-linking and gelation of low-methoxy pectins are basic processes commonly used in different industries. The aim of this research was to evaluate the cross-linking process of the sodium carbonate-soluble pectins (named DASP) extracted from apples, characterized by a low degree of methylesterification [...] Read more.
The cross-linking and gelation of low-methoxy pectins are basic processes commonly used in different industries. The aim of this research was to evaluate the cross-linking process of the sodium carbonate-soluble pectins (named DASP) extracted from apples, characterized by a low degree of methylesterification as a function of its concentration in water (CDASP). The cross-linking process was studied with a dynamic light scattering method, atomic force microscope (AFM), viscosity and pH measurements. An increase in CDASP above 0.01% resulted in a decrease in the aggregation index (AI) and the change of its sign from positive to negative. The value of AI = 0 occurred at CDASP = 0.33 ± 0.04% and indicated the formation of a pectin network. An increase in CDASP caused the changes in viscosity of pectin solutions and the nanostructure of pectins spin-coated on mica observed with AFM, which confirmed results obtained. The hydrogen bonds were involved in the cross-linking process. Full article
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Open AccessArticle
Microwave-Assisted Extraction, Purification, Partial Characterization, and Bioactivity of Polysaccharides from Panax ginseng
Molecules 2019, 24(8), 1605; https://doi.org/10.3390/molecules24081605
Received: 30 March 2019 / Revised: 18 April 2019 / Accepted: 18 April 2019 / Published: 23 April 2019
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Abstract
Polysaccharides are a main active substance in Panax ginseng; however, microwave-assisted extraction used to prepare P. ginseng polysaccharides (MPPG) has rarely been reported, and knowledge of the bactericidal activity of P. ginseng polysaccharides remains low. Thus, this study was designed to investigate [...] Read more.
Polysaccharides are a main active substance in Panax ginseng; however, microwave-assisted extraction used to prepare P. ginseng polysaccharides (MPPG) has rarely been reported, and knowledge of the bactericidal activity of P. ginseng polysaccharides remains low. Thus, this study was designed to investigate the extraction of P. ginseng polysaccharides by using two methods—hot water extraction and microwave-assisted extraction—and compare their chemical composition and structure. In addition, their antibacterial and antioxidant activities were also determined. The data implied that P. ginseng polysaccharides extracted by microwave-assisted extraction possessed a higher extraction yield than hot water extraction (WPPG) under optimized conditions, and the actual yields were 41.6% ± 0.09% and 28.5% ± 1.62%, respectively. Moreover, the preliminary characterization of polysaccharides was identified after purification. The WPPG with the molecular weight (Mw) of 2.07 × 105 Da was composed of Man, Rib, Rha, GalA, Glu, Gal, and Arab, and the typical characteristics of polysaccharides were determined by IR spectra. Compared with WPPG, MPPG had a higher Mw, uronic acid content, and Glu content. More importantly, the antioxidant activity of MPPG was higher than WPPG, which was probably ascribed to its highly Mw and abundant uronic acid content. Besides, both of them exhibited high bactericidal activity. These results demonstrate that microwave-assisted extraction is an effective method for obtaining P. ginseng polysaccharides, and MPPG could be applied as an antioxidant and antibacterial agent. Full article
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Open AccessArticle
Polysaccharide-Rich Fractions from Rosa rugosa Thunb.—Composition and Chemopreventive Potential
Molecules 2019, 24(7), 1354; https://doi.org/10.3390/molecules24071354
Received: 14 March 2019 / Revised: 30 March 2019 / Accepted: 4 April 2019 / Published: 6 April 2019
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Abstract
The huge health-beneficial potential of polysaccharides encourages the search for novel sources and applications of these compounds. One poorly explored source of polysaccharides is the rose. The content and biological activity of polysaccharides in rose organs is an almost completely unaddressed topic, therefore, [...] Read more.
The huge health-beneficial potential of polysaccharides encourages the search for novel sources and applications of these compounds. One poorly explored source of polysaccharides is the rose. The content and biological activity of polysaccharides in rose organs is an almost completely unaddressed topic, therefore, polysaccharide-rich extracts (crude polysaccharides, CPLs) from petals, leaves, hips, and achenes of Rosa rugosa Thunb. were studied for their composition and the influence on various cellular processes involved in the development of cancer and other civilization diseases. The study revealed the presence of water-soluble and -insoluble polysaccharides (including β-glucans) and protein-polysaccharide conjugates in rose organs. Rose hips were found to be the most abundant source of polysaccharides. Different polysaccharide-rich extracts showed the ability to inhibit pro-inflammatory enzymes (COX-1, COX-2, hyaluronidase), a radical scavenging effect (against DPPH and ABTS•+), and antiproliferative activity (in the A549 lung and SW480 colon cancer cell lines) in in vitro assays. Therefore, rose crude polysaccharides are very promising and can potentially be used as natural chemopreventive agents. Full article
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Open AccessArticle
Structure and Anti-Tumor Activities of Exopolysaccharides from Alternaria mali Roberts
Molecules 2019, 24(7), 1345; https://doi.org/10.3390/molecules24071345
Received: 3 March 2019 / Revised: 1 April 2019 / Accepted: 2 April 2019 / Published: 5 April 2019
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Abstract
In this study, an extracellular polysaccharide from Alternaria mali Roberts (AMEP) was extracted, and its structure was characterized, in addition to its antitumor activity in vitro. Neutral polysaccharide AMEP-1 and anionic polysaccharide AMEP-2 were isolated from AMEP, and their monosaccharide compositions consisted of [...] Read more.
In this study, an extracellular polysaccharide from Alternaria mali Roberts (AMEP) was extracted, and its structure was characterized, in addition to its antitumor activity in vitro. Neutral polysaccharide AMEP-1 and anionic polysaccharide AMEP-2 were isolated from AMEP, and their monosaccharide compositions consisted of mannose (Man), glucose (Glc), and galactose (Gal) but at different ratios. The linking mode of both AMEP-1 and AMEP-2 is Manp-(1→4) and Glcp-(1→6), and the branched chains are connected to the main chain through O-6. AMEP-2 inhibited the proliferation of BGC-823 cells in a time- and concentration-dependent manner. AMEP-2 also induced the apoptosis of BGC-823 cells, and showed anti-tumor effects by inducing cell cycle arrest in the S phase, reactive oxygen species production, and mitochondrial membrane potential reduction in BGC-823 cells. Therefore, AMEP-2 shows potential for further development as a novel anti-tumor agent. Full article
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Open AccessArticle
Characterization of Inulin-Type Fructan from Platycodon grandiflorus and Study on Its Prebiotic and Immunomodulating Activity
Molecules 2019, 24(7), 1199; https://doi.org/10.3390/molecules24071199
Received: 28 February 2019 / Revised: 17 March 2019 / Accepted: 25 March 2019 / Published: 27 March 2019
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Abstract
Platycodon grandiflorus is a plant widely used in traditional Chinese medicine, of which polysaccharides are reported to be the main components responsible for its bio-functions. In this work, the inulin-type fructan (PGF) was obtained by DEAE anion exchange chromatography from the water extracted [...] Read more.
Platycodon grandiflorus is a plant widely used in traditional Chinese medicine, of which polysaccharides are reported to be the main components responsible for its bio-functions. In this work, the inulin-type fructan (PGF) was obtained by DEAE anion exchange chromatography from the water extracted from P. grandifloras. Characterization was performed with methanolysis, methylation, and NMR and the results showed that PGF is a β-(2-1) linked fructan, with terminal glucose and with a degree of polymerization of 2–10. In order to study its biofunctions, the prebiotic and immunomodulation properties were assayed. We found that PGF exhibited good prebiotic activity, as shown by a promotion on six strains of lactobacillus proliferation. Additionally, the PGF also displayed direct immunomodulation on intestinal epithelial cells and stimulated the expressions of anti-inflammatory factors. These results indicated that the inulin from P. grandiflorus is a potential natural source of prebiotics as well as a potential intestinal immunomodulator, which will be valuable for further studies and new applications. Full article
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Open AccessArticle
Effects of a Lysine-Involved Maillard Reaction on the Structure and In Vitro Activities of Polysaccharides from Longan Pulp
Molecules 2019, 24(5), 972; https://doi.org/10.3390/molecules24050972
Received: 24 February 2019 / Revised: 5 March 2019 / Accepted: 6 March 2019 / Published: 10 March 2019
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Abstract
The effects of amino acid-involved Maillard reactions (MRs) on the structure and activities of longan pulp polysaccharides (LPs), which were heteropolysaccharides mainly composed of glucose, galactose, mannose, rhamnose, glucuronic acid, ribose, and galacturonic acid, were investigated. The changes of browning degree and molecular [...] Read more.
The effects of amino acid-involved Maillard reactions (MRs) on the structure and activities of longan pulp polysaccharides (LPs), which were heteropolysaccharides mainly composed of glucose, galactose, mannose, rhamnose, glucuronic acid, ribose, and galacturonic acid, were investigated. The changes of browning degree and molecular weight (Mw) distribution in the MR systems containing LPs and amino acids (lysine, proline, or glycine) indicated that lysine was more active in conjugating with LPs. The MR-modified LPs (MLPs) obtained via a 4 h MR between LPs and lysine showed obvious structural differences from LPs. Specifically, particle-like LPs contained 94% fractions with a Mw less than 7.07 kDa, by contrast, network-like MLPs contained 45% fractions with a Mw larger than 264.1 kDa. Moreover, MLPs showed stronger radical scavenging abilities and macrophage immunostimulating effects, but weaker cancer cell growth-inhibitory abilities. The results indicate that the amino acid-involved MR is a promising method to modify native polysaccharides for better biological properties. Full article
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Open AccessArticle
Partial Characterization, the Immune Modulation and Anticancer Activities of Sulfated Polysaccharides from Filamentous Microalgae Tribonema sp.
Molecules 2019, 24(2), 322; https://doi.org/10.3390/molecules24020322
Received: 17 December 2018 / Revised: 14 January 2019 / Accepted: 14 January 2019 / Published: 17 January 2019
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Abstract
Recently, Tribonema sp., a kind of filamentous microalgae, has been studied for biofuel production due to its accumulation of triacylglycerols. However, the polysaccharides of Tribonema sp. and their biological activities have rarely been reported. In this paper, we extracted sulfated polysaccharides from Tribonema [...] Read more.
Recently, Tribonema sp., a kind of filamentous microalgae, has been studied for biofuel production due to its accumulation of triacylglycerols. However, the polysaccharides of Tribonema sp. and their biological activities have rarely been reported. In this paper, we extracted sulfated polysaccharides from Tribonema sp. (TSP), characterized their chemical composition and structure, and determined their immunostimulation and anticancer activities on RAW264.7 macrophage cells and HepG2 cells. The results showed that TSP is a sulfated polysaccharide with a Mw of 197 kDa. TSP is a heteropolysaccharide that is composed mainly of galactose. It showed significant immune-modulatory activity by stimulating macrophage cells, such as upregulating interleukin 6 (IL-6), interleukin 10 (IL-10), and tumor necrosis factor α (TNF-α). In addition, TSP also showed significant dose-dependent anticancer activity (with an inhibition rate of up to 66.8% at 250 µg/mL) on HepG2 cells as determined by the 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The cycle analysis indicated that the anticancer activity of TSP is mainly the result of induced cell apoptosis rather than affecting the cell cycle and mitosis of HepG2 cells. These findings suggest that TSP might have potential as an anticancer resource, but further research is needed, especially in vivo experiments, to explore the anticancer mechanism of TSP. Full article
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Review

Jump to: Research

Open AccessReview
Extraction, Purification, Structural Characteristics, Biological Activities and Pharmacological Applications of Acemannan, a Polysaccharide from Aloe vera: A Review
Molecules 2019, 24(8), 1554; https://doi.org/10.3390/molecules24081554
Received: 26 March 2019 / Revised: 11 April 2019 / Accepted: 17 April 2019 / Published: 19 April 2019
PDF Full-text (1679 KB) | HTML Full-text | XML Full-text
Abstract
Aloe vera is a medicinal plant species of the genus Aloe with a long history of usage around the world. Acemannan, considered one of the main bioactive polysaccharides of Aloe vera, possesses immunoregulation, anti-cancer, anti-oxidation, wound healing and bone proliferation promotion, neuroprotection, [...] Read more.
Aloe vera is a medicinal plant species of the genus Aloe with a long history of usage around the world. Acemannan, considered one of the main bioactive polysaccharides of Aloe vera, possesses immunoregulation, anti-cancer, anti-oxidation, wound healing and bone proliferation promotion, neuroprotection, and intestinal health promotion activities, among others. In this review, recent advancements in the extraction, purification, structural characteristics and biological activities of acemannan from Aloe vera were summarized. Among these advancements, the structural characteristics of purified polysaccharides were reviewed in detail. Meanwhile, the biological activities of acemannan from Aloe vera determined by in vivo, in vitro and clinical experiments are summarized, and possible mechanisms of these bioactivities were discussed. Moreover, the latest research progress on the use of acemannan in dentistry and wound healing was also summarized in details. The structure-activity relationships of acemannan and its medical applications were discussed. Finally, new perspectives for future research work on acemannan were proposed. In conclusion, this review summarizes the extraction, purification, structural characteristics, biological activities and pharmacological applications of acemannan, and provides information for the industrial production and possible applications in dentistry and wound healing in the future. Full article
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Open AccessFeature PaperReview
Chondroitin Sulfate Safety and Quality
Molecules 2019, 24(8), 1447; https://doi.org/10.3390/molecules24081447
Received: 7 March 2019 / Revised: 8 April 2019 / Accepted: 9 April 2019 / Published: 12 April 2019
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Abstract
The industrial production of chondroitin sulfate (CS) uses animal tissue sources as raw material derived from different terrestrial or marine species of animals. CS possesses a heterogeneous structure and physical-chemical profile in different species and tissues, responsible for the various and more specialized [...] Read more.
The industrial production of chondroitin sulfate (CS) uses animal tissue sources as raw material derived from different terrestrial or marine species of animals. CS possesses a heterogeneous structure and physical-chemical profile in different species and tissues, responsible for the various and more specialized functions of these macromolecules. Moreover, mixes of different animal tissues and sources are possible, producing a CS final product having varied characteristics and not well identified profile, influencing oral absorption and activity. Finally, different extraction and purification processes may introduce further modifications of the CS structural characteristics and properties and may lead to extracts having a variable grade of purity, limited biological effects, presence of contaminants causing problems of safety and reproducibility along with not surely identified origin. These aspects pose a serious problem for the final consumers of the pharmaceutical or nutraceutical products mainly related to the traceability of CS and to the declaration of the real origin of the active ingredient and its content. In this review, specific, sensitive and validated analytical quality controls such as electrophoresis, eHPLC (enzymatic HPLC) and HPSEC (high-performance size-exclusion chromatography) able to assure CS quality and origin are illustrated and discussed. Full article
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Planned Papers

The below list represents only planned manuscripts. Some of these manuscripts have not been received by the Editorial Office yet. Papers submitted to MDPI journals are subject to peer-review.

Alkylchitosan-Based Adhesive: Water Resistance Improvement

Narimane Mati-Baouche1,2, Cédric Delattre1, de Baynast Hélène1, Michel Grédiac1, Jean-Denis Mathias3, Alina Violeta Ursu1, Jacques Desbrières4,* and Philippe Michaud1

1Université Clermont Auvergne, CNRS, SIGMA Clermont, Institut Pascal, F-63000 Clermont-Ferrand, France

2Laboratoire Glyco-MEV EA 4358, Fédération de recherche Normandie-Végétal - FED 4277, Université de Rouen Normandie, Bâtiment CURIB 25 Rue Lucien Tesnière, 76821 Mont-Saint-Aignan, France

3IRSTEA, Laboratoire d’Ingénierie pour les Systèmes Complexes, 9 avenue Blaise Pascal, CS 20085, 63178 Aubière, France

4Université de Pau et des Pays de l’Adour (UPPA), Hélioparc Pau Pyrénées, 2 avenue P. Angot, 64053 PAU cedex 09, France

*Correspondence: [email protected] (Jacques Desbrieres); Tél.: + 33 5 59 40 76 02

Abstract: Chemical modification by grafting alkyl chains on chitosan was conducted with the aim to improve its water resistance for bonding applications. The chemical structure of modified polymers was determined by NMR analyses. Yields of alkylation of 10 and 15 % were obtained using octanal (C8). The flow properties of solutions with three concentrations of alkylated chitosan were evaluated revealing an increase of viscosity comparing to the same solutions with native chitosan. The evaluation of the adhesive strength of both native and grafted (modified) chitosans was performed on two different adherent double lap systems (aluminum and wood). Alkylated chitosans (10 and 15%) keep sufficient adhesive properties on wood and exhibit a better water resistance comparing to native one.

Keywords: Chitosan; alkylation; adhesive; water resistance

 

What’s in store for EPS microalgae in the next decade?

Guillaume Pierre 1, Cédric Delattre 1, Pascal Dubessay 1, Sébastien Jubeau 2, Carole Vialleix 3, Jean-Paul Cadoret 3 Ian Probert 4 and Philippe Michaud 1,*

1   Université Clermont Auvergne, CNRS, SIGMA Clermont, Institut Pascal, F-63000 CLERMONT-FERRAND, FRANCE; [email protected]

2   Xanthella, Malin House, European Marine Science Park, Dunstaffnage, Argyll, Oban PA37 1SZ SCOTLAND; [email protected]

3   GreenSea Biotechnologies, Promenade du sergent Navarro, 34140 MEZE, FRANCE; [email protected]

4   Station Biologique de Roscoff, Place Georges Teissier, 29680 ROSCOFF, FRANCE; [email protected]

*  Correspondence: [email protected]; Tel.: +33 (0)4-73-40-74-25

Abstract: Microalgae and their metabolites are still an Eldorado since the turn of the XXIe century. Many scientific works and industrial exploitations have thus been set up. These developments have often highlighted the need to intensify the processes for biomass production in photo-autotrophy and exploit all the microalgae value including ExoPolySaccharides (EPS). Indeed, the bottlenecks limiting the development of low value products from microalgae are not linked to biology but to biological engineering problems including harvesting, recycling of culture media, photoproduction, and biorefinery. Even respecting the so-called “Biorefinery Concept”, few applications had chance to emerge and live on the market. Thus, exploiting microalgae and their EPS to access in some low value markets such as food is probably not mature considering the competitiveness of polysaccharides from terrestrial plants, macroalgae and bacteria. However, it does not imply to draw a line on their uses but rather to “think them” differently. This review provides insights into microalgae, EPS and their exploitation. Perspectives on issues affecting the future of EPS microalgae are also addressed with a critical point of view.

Keywords: microalgae; exopolysaccharides; EPS; application; market.

 

Safety and Quality Concerns of Animal-Derived Chondroitin Sulfate

Nicola Volpi

Department of Life Sciences, Laboratory of Biochemistry and Glycobiology, University of Modena and Reggio Emilia, Italy

Correspondence: nicola.[email protected]; Tel +39 59 2055543; Fax +39 59 2055548

Abstract: The industrial production of chondroitin sulfate (CS) uses animal tissue sources as raw material derived from different species of animals, in particular from bovine, porcine, chicken or cartilaginous fishes such as sharks and skate. Minor production is also from bony fishes by-products. CS possess a heterogeneous structure and physical-chemical profile in different species and tissues, responsible for the various and more specialized functions of these macromolecules. Moreover, mixes of different animal tissues and sources are possible, producing a CS final product having varied characteristics and not well identified profile, influencing oral absorption and activity. Finally, different extraction and purification processes may introduce further modifications of the CS structural characteristics and properties and may led to extracts having a variable grade of purity, limited biological effects, presence of contaminants causing problems of safety and reproducibility along with not sure identified origin. These aspects pose a serious problem for the final consumers of the pharmaceutical or nutraceutical products that is related to the declaration in label of the real origin of the active ingredient and its content and to the label traceability of CS.

Keywords: Chondroitin sulfate; Glycosaminoglycans; Osteoarthritis; Nutraceuticals; Food supplements

 

Prospect Of Polysaccharide-Based Materials As Advanced Food Packaging

Aleksandra Nesić 1,3, Suzana Dimitrijevic-Branković 2,*, Sladjana Davidović 2, Neda Radovanović 5 and CédricDelattre 4

University of Belgrade, Vinca Institute for Nuclear Sciences, Mike Petrovica-Alasa 12-14, Belgrade, Serbia

University of Belgrade, Faculty of Technology and Metallurgy, Karnegijeva 4, Belgrade, Serbia

University of Concepcion, Technological Development Unit, Avda. Cordillera No. 2634, Parque Industrial Coronel, Coronel. Chile

Université Clermont Auvergne, CNRS, SIGMA Clermont, Institut Pascal, F-63000 Clermont-Ferrand, France

5   University of Belgrade, Inovation Centre of Faculty of Technology and Metallurgy, Karnegijeva 4, Belgrade, Serbia

Correspondence: [email protected]

Abstract: The use of polysaccharide-based materials presents an eco-friendly technological solution, by reducing dependence on fossil resources whilst improving a product’s carbon footprint, when compared to conventional plastic packaging materials. This reviewdiscusses the potential of polysaccharides as a raw material for the production of multifunctional materials for food packaging applications. Areas covered include the production and properties of the various types of polysaccharidematerials. Particular emphasis is given to hemicelluloses, marine polysaccharides and bacterial exopolysaccharides and their potential application in latest trend of food packaging materials, including edible coatings, intelligent films and thermo-insulated aerogel packaging.

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