Marine Drugs

Research

12 pages, 1148 KiB

Open AccessArticle

Structure of the Exopolysaccharide Secreted by a Marine Strain Vibrio alginolyticus

by Sophie Drouillard, Isabelle Jeacomine, Laurine Buon, Claire Boisset, Anthony Courtois, Bertrand Thollas, Pierre-Yves Morvan, Romuald Vallée and William Helbert

Mar. Drugs 2018, 16(5), 164; https://doi.org/10.3390/md16050164 - 15 May 2018

Cited by 14 | Viewed by 4824

Abstract

Vibrio alginolyticus (CNCM I-4151) secretes an exopolysaccharide whose carbohydrate backbone is decorated with amino acids, likely conferring its properties that are appreciated in cosmetics. Here, the secreted polysaccharide of another strain of V. alginolyticus (CNCM I-5034) was characterized by chromatography and one- and [...] Read more.

Vibrio alginolyticus (CNCM I-4151) secretes an exopolysaccharide whose carbohydrate backbone is decorated with amino acids, likely conferring its properties that are appreciated in cosmetics. Here, the secreted polysaccharide of another strain of V. alginolyticus (CNCM I-5034) was characterized by chromatography and one- and two-dimensional NMR spectroscopy experiments. The structure was resolved and shows that the carbohydrate backbone is made of four residues: D-galactose (Gal), D-galacturonic acid (GalA) D-N-acetylglucosamine (GlcNAc) and D-glucuronic acid (GlcA), forming a tetrasaccharide repetition unit [→4)-β-d-GlcA-(1→3)-α-d-Gal-(1→3)-α-d-GalA-(1→3)-β-GlcNAc(1→]. GlcA is derivatized with a lactate group giving ‘nosturonic acid’, and GalA is decorated with the amino acid alanine. Full article

(This article belongs to the Special Issue Marine Oligosaccharides and Polysaccharides)

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16 pages, 19626 KiB

Open AccessArticle

Fucoidan Rescues p-Cresol-Induced Cellular Senescence in Mesenchymal Stem Cells via FAK-Akt-TWIST Axis

by Jun Hee Lee, Chul Won Yun, Jin Hur and Sang Hun Lee

Mar. Drugs 2018, 16(4), 121; https://doi.org/10.3390/md16040121 - 6 Apr 2018

Cited by 40 | Viewed by 5351

Abstract

Mesenchymal stem cells (MSCs) are a source for cell-based therapy. Although MSCs have the potential for tissue regeneration, their therapeutic efficacy is restricted by the uremic toxin, p-cresol, in chronic kidney disease (CKD). To address this issue, we investigated the effect of [...] Read more.

Mesenchymal stem cells (MSCs) are a source for cell-based therapy. Although MSCs have the potential for tissue regeneration, their therapeutic efficacy is restricted by the uremic toxin, p-cresol, in chronic kidney disease (CKD). To address this issue, we investigated the effect of fucoidan, a marine sulfated polysaccharide, on cellular senescence in MSCs. After p-cresol exposure, MSC senescence was induced, as indicated by an increase in cell size and a decrease in proliferation capacity. Treatment of senescent MSCs with fucoidan significantly reversed this cellular senescence via regulation of SMP30 and p21, and increased proliferation through the regulation of cell cycle-associated proteins (CDK2, CDK4, cyclin D1, and cyclin E). These effects were dependent on FAK-Akt-TWIST signal transduction. In particular, fucoidan promoted the expression of cellular prion protein (PrP^C), which resulted in the maintenance of cell expansion capacity in p-cresol-induced senescent MSCs. This protective effect of fucoidan on senescence-mediated inhibition of proliferation was dependent on the TWIST-PrP^C axis. In summary, this study shows that fucoidan protects against p-cresol-induced cellular senescence in MSCs through activation of the FAK-Akt-TWIST pathway and suggests that fucoidan could be used in conjunction with functional MSC-based therapies in the treatment of CKD. Full article

(This article belongs to the Special Issue Marine Oligosaccharides and Polysaccharides)

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19 pages, 10831 KiB

Open AccessArticle

Association of Alpha Tocopherol and Ag Sulfadiazine Chitosan Oleate Nanocarriers in Bioactive Dressings Supporting Platelet Lysate Application to Skin Wounds

by Maria Cristina Bonferoni, Giuseppina Sandri, Silvia Rossi, Eleonora Dellera, Alessandro Invernizzi, Cinzia Boselli, Antonia Icaro Cornaglia, Claudia Del Fante, Cesare Perotti, Barbara Vigani, Federica Riva, Carla Caramella and Franca Ferrari

Mar. Drugs 2018, 16(2), 56; https://doi.org/10.3390/md16020056 - 9 Feb 2018

Cited by 22 | Viewed by 4993

Abstract

Chitosan oleate was previously proposed to encapsulate in nanocarriers some poorly soluble molecules aimed to wound therapy, such as the anti-infective silver sulfadiazine, and the antioxidant α tocopherol. Because nanocarriers need a suitable formulation to be administered to wounds, in the present paper, [...] Read more.

Chitosan oleate was previously proposed to encapsulate in nanocarriers some poorly soluble molecules aimed to wound therapy, such as the anti-infective silver sulfadiazine, and the antioxidant α tocopherol. Because nanocarriers need a suitable formulation to be administered to wounds, in the present paper, these previously developed nanocarriers were loaded into freeze dried dressings based on chitosan glutamate. These were proposed as bioactive dressings aimed to support the application to wounds of platelet lysate, a hemoderivative rich in growth factors. The dressings were characterized for hydration capacity, morphological aspect, and rheological and mechanical behavior. Although chitosan oleate nanocarriers clearly decreased the mechanical properties of dressings, these remained compatible with handling and application to wounds. Preliminary studies in vitro on fibroblast cell cultures demonstrated good compatibility of platelet lysate with nanocarriers and bioactive dressings. An in vivo study on a murine wound model showed an accelerating wound healing effect for the bioactive dressing and its suitability as support of the platelet lysate application to wounds. Full article

(This article belongs to the Special Issue Marine Oligosaccharides and Polysaccharides)

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8 pages, 5950 KiB

Open AccessArticle

Formation of Silver Nanoparticles Using Fluorescence Properties of Chitosan Oligomers

by Ja Young Cheon, Hun Min Lee and Won Ho Park

Mar. Drugs 2018, 16(1), 11; https://doi.org/10.3390/md16010011 - 3 Jan 2018

Cited by 5 | Viewed by 4547

Abstract

In this study, silver chloride nanoparticles (AgCl NPs) were prepared using chitosan oligomer (CHI) and chitosan oligomer derivatives (CHI-FITC). The CHI and CHI-FITC were used as markers to confirm the formation of AgCl NPs using their fluorescence properties as well as stabilizers. The [...] Read more.

In this study, silver chloride nanoparticles (AgCl NPs) were prepared using chitosan oligomer (CHI) and chitosan oligomer derivatives (CHI-FITC). The CHI and CHI-FITC were used as markers to confirm the formation of AgCl NPs using their fluorescence properties as well as stabilizers. The fluorescence properties of CHI and CHI-FITC were monitored by a luminescence spectrophotometer, and the morphology of the AgCl NPs was further confirmed by transmission electron microscopy (TEM) and X-ray diffraction (XRD). The fluorescence of CHI and CHI-FITC was quenched by the formation of AgCl NPs, and the Stern–Volmer equation was used to compare the two types of stabilizer. The CHI and CHI-FITC stabilizer were linear and nonlinear, respectively, with respect to the Stern–Volmer equation, and considered to be usable as fluorescence indicators to confirm the formation behavior of AgCl NPs through fluorescence quenching. Full article

(This article belongs to the Special Issue Marine Oligosaccharides and Polysaccharides)

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2422 KiB

Open AccessArticle

Characterization of a Long-Lived Alginate Lyase Derived from Shewanella Species YH1

by Hisashi Yagi, Natsuki Isobe, Narumi Itabashi, Asako Fujise and Takashi Ohshiro

Mar. Drugs 2018, 16(1), 4; https://doi.org/10.3390/md16010004 - 27 Dec 2017

Cited by 10 | Viewed by 4123

Abstract

Polysaccharides from seaweeds are widely used in various fields, including the food, biomedical material, cosmetic, and biofuel industries. Alginate, which is a major polysaccharide in brown algae, and the products of its degradation (oligosaccharides) have been used in stabilizers, thickeners, and gelling agents, [...] Read more.

Polysaccharides from seaweeds are widely used in various fields, including the food, biomedical material, cosmetic, and biofuel industries. Alginate, which is a major polysaccharide in brown algae, and the products of its degradation (oligosaccharides) have been used in stabilizers, thickeners, and gelling agents, especially in the food industry. Discovering novel alginate lyases with unique characteristics for the efficient production of oligosaccharides may be relevant for the food and pharmaceutical fields. In this study, we identified a unique alginate lyase derived from an alginate-utilizing bacterium, Shewanella species YH1. The recombinant enzyme (rAlgSV1-PL7) was produced in an Escherichia coli system and it was classified in the Polysaccharide Lyase family 7. The optimal temperature and pH for rAlgSV1-PL7 activity were around 45 °C and 8, respectively. Interestingly, we observed that rAlgSV1-PL7 retained over 80% of its enzyme activity after incubation at 30 °C for at least 20 days, indicating that rAlgSV1-PL7 is a long-lived enzyme. Moreover, the degradation of alginate by rAlgSV1-PL7 produced one to four sugars because of the broad substrate specificity of this enzyme. Our findings suggest that rAlgSV1-PL7 may represent a new commercially useful enzyme. Full article

(This article belongs to the Special Issue Marine Oligosaccharides and Polysaccharides)

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1650 KiB

Open AccessFeature PaperArticle

Chitosan Nanoparticles as a Mucoadhesive Drug Delivery System for Ocular Administration

by Mariana M. Silva, Raquel Calado, Joana Marto, Ana Bettencourt, António J. Almeida and Lídia M. D. Gonçalves

Mar. Drugs 2017, 15(12), 370; https://doi.org/10.3390/md15120370 - 1 Dec 2017

Cited by 193 | Viewed by 10705

Abstract

Pharmaceutical approaches based on nanotechnologies and the development of eye drops composed of the mucoadhesive polymers chitosan and hyaluronic acid are emerging strategies for the efficient treatment of ocular diseases. These innovative nanoparticulate systems aim to increase drugs’ bioavailability at the ocular surface. [...] Read more.

Pharmaceutical approaches based on nanotechnologies and the development of eye drops composed of the mucoadhesive polymers chitosan and hyaluronic acid are emerging strategies for the efficient treatment of ocular diseases. These innovative nanoparticulate systems aim to increase drugs’ bioavailability at the ocular surface. For the successful development of these systems, the evaluation of mucoahesiveness (the interaction between the ocular delivery system and mucins present on the eye) is of utmost importance. In this context, the aim of the present work was to investigate the mucoadhesivity of a novel nanoparticle eye drop formulation containing an antibiotic (ceftazidime) intended to treat eye infections. Eye drop formulations comprised a polymer (hydroxypropyl) methyl cellulose (HPMC) 0.75% (w/v) in an isotonic solution incorporating chitosan/sodium tripolyphosphate (TPP)-hyaluronic acid-based nanoparticles containing ceftazidime. The viscosity of the nanoparticles, and the gels incorporating the nanoparticles were characterized in contact with mucin at different mass ratios, allowing the calculation of the rheological synergism parameter (∆η). Results showed that at different nanoparticle eye formulation:mucin weight ratios, a minimum in viscosity occurred which resulted in a negative rheological synergism. Additionally, the results highlighted the mucoadhesivity of the novel ocular formulation and its ability to interact with the ocular surface, thus increasing the drug residence time in the eye. Moreover, the in vitro release and permeation studies showed a prolonged drug release profile from the chitosan/TPP-hyaluronic acid nanoparticles gel formulation. Furthermore, the gel formulations were not cytotoxic on ARPE-19 and HEK293T cell lines, evaluated by the metabolic and membrane integrity tests. The formulation was stable and the drug active, as shown by microbiological studies. In conclusion, chitosan/TPP-hyaluronic acid nanoparticle eye drop formulations are a promising platform for ocular drug delivery with enhanced mucoadhesive properties. Full article

(This article belongs to the Special Issue Marine Oligosaccharides and Polysaccharides)

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1325 KiB

Open AccessArticle

Isolation and Characterization of Polysaccharides from Oysters (Crassostrea gigas) with Anti-Tumor Activities Using an Aqueous Two-Phase System

by Kit-Leong Cheong, Li-Xuan Xia and Yang Liu

Mar. Drugs 2017, 15(11), 338; https://doi.org/10.3390/md15110338 - 1 Nov 2017

Cited by 44 | Viewed by 5951

Abstract

In this study, a simple aqueous two-phase system (ATPS) was employed for concurrent purification of oyster polysaccharides. The chemical structure and anti-tumor activities of purified oyster polysaccharides (OP-1) were also investigated. Under optimal ATPS conditions, oyster polysaccharides can be partitioned in the bottom [...] Read more.

In this study, a simple aqueous two-phase system (ATPS) was employed for concurrent purification of oyster polysaccharides. The chemical structure and anti-tumor activities of purified oyster polysaccharides (OP-1) were also investigated. Under optimal ATPS conditions, oyster polysaccharides can be partitioned in the bottom phase with 67.02% extraction efficiency. The molecular weight of OP-1 was determined as 3480 Da. OP-1 is a (1→4)-α-d-glucosyl backbone and branching points located at O-3 of glucose with a terminal-d-Glcp. The anti-tumor activity assay showed that OP-1 exhibited good activities, including promotion of splenocyte proliferation, IL-2 release, and inhibition of HepG2 cell proliferation. Additionally, OP-1 had no in vivo toxicity. This finding suggests that ATPS is a much simpler and greener system, and it opens up new possibilities in the large-scale separation of active polysaccharides from oysters. OP-1 could be used by the health food and pharmaceutical therapies as potential anti-cancer adjuvants. Full article

(This article belongs to the Special Issue Marine Oligosaccharides and Polysaccharides)

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4648 KiB

Open AccessArticle

Release Behavior and Antibacterial Activity of Chitosan/Alginate Blends with Aloe vera and Silver Nanoparticles

by Luisa Fernanda Gómez Chabala, Claudia Elena Echeverri Cuartas and Martha Elena Londoño López

Mar. Drugs 2017, 15(10), 328; https://doi.org/10.3390/md15100328 - 24 Oct 2017

Cited by 87 | Viewed by 8301

Abstract

Aloe vera is a perennial plant employed for medical, pharmaceutical and cosmetic purposes that is rich in amino acids, enzymes, vitamins and polysaccharides, which are responsible for its therapeutic properties. Incorporating these properties into a biopolymer film obtained from alginate and chitosan allowed [...] Read more.

Aloe vera is a perennial plant employed for medical, pharmaceutical and cosmetic purposes that is rich in amino acids, enzymes, vitamins and polysaccharides, which are responsible for its therapeutic properties. Incorporating these properties into a biopolymer film obtained from alginate and chitosan allowed the development of a novel wound dressing with antibacterial capacity and healing effects to integrate the antibacterial capacity of silver nanoparticles with the healing and emollient properties of Aloe vera gel. Three alginate-chitosan matrices were obtained through blending methods using different proportions of alginate, chitosan, the Aloe vera (AV) gel and silver nanoparticles (AgNps), which were incorporated into the polymeric system through immersion methods. Physical, chemical and antibacterial characteristics were evaluated in each matrix. Interaction between alginate and chitosan was identified using the Fourier transform infrared spectroscopy technique (FTIR), porosity was studied using scanning electron microscopy (SEM), swelling degree was calculated by difference in weight, Aloe vera gel release capacity was estimated by applying a drug model (Peppas) and finally antibacterial capacity was evaluated against S. Aureus and P. aeruginosa. Results show that alginate-chitosan (A (1:3 Chit 1/Alg 1); B (1:3 Chit 1.5/Alg 1) and C (3:1 Chit 1/Alg 1/B12)) matrices with Aloe vera (AV) gel and silver nanoparticles (AgNps) described here displayed antibacterial properties and absorption and Aloe vera release capacity making it a potential wound dressing for minor injuries. Full article

(This article belongs to the Special Issue Marine Oligosaccharides and Polysaccharides)

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2149 KiB

Open AccessArticle

Synthesis and Evaluation of a Sodium Alginate-4-Aminosalicylic Acid Based Microporous Hydrogel for Potential Viscosupplementation for Joint Injuries and Arthritis-Induced Conditions

by Dharmesh R. Chejara, Mostafa Mabrouk, Pradeep Kumar, Yahya E. Choonara, Pierre P. D. Kondiah, Ravindra V. Badhe, Lisa C. du Toit, Divya Bijukumar and Viness Pillay

Mar. Drugs 2017, 15(8), 257; https://doi.org/10.3390/md15080257 - 16 Aug 2017

Cited by 9 | Viewed by 5496

Abstract

A microporous hydrogel was developed using sodium alginate (alg) and 4-aminosalicylic acid (4-ASA). The synthesized hydrogel was characterized using various analytical techniques such as Fourier transform infrared spectroscopy (FTIR), Carbon-13 nuclear magnetic resonance (¹³C-NMR), X-ray powder diffraction (XRD), scanning electron microscopy [...] Read more.

A microporous hydrogel was developed using sodium alginate (alg) and 4-aminosalicylic acid (4-ASA). The synthesized hydrogel was characterized using various analytical techniques such as Fourier transform infrared spectroscopy (FTIR), Carbon-13 nuclear magnetic resonance (¹³C-NMR), X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and differential scanning calorimetry (DSC). Additonal carboxyl and hydroxyl functional groups of 4-ASA provided significant lubrication and stress-triggered sol-gel transition to the conjugated hydrogel. In addition, cytotoxicity analysis was undertaken on the conjugated hydrogel using human dermal fibroblast-adult (HDFa) cells, displaying non-toxic characteristics. Drug release profiles displaying 49.6% in the first 8 h and 97.5% within 72 h, similar to the native polymer (42.8% in first 8 h and 90.1% within 72 h). Under applied external stimuli, the modified hydrogel displayed significant gelling properties and structure deformation/recovery behaviour, confirmed using rheological evaluation (viscosity and thixotropic area of 8095.3 mPas and 26.23%, respectively). The modified hydrogel, thus, offers great possibility for designing smart synovial fluids as a biomimetic aqueous lubricant for joint-related injuries and arthritis-induced conditions. In addtion, the combination of thixotropy, non-toxicity, and drug release capabilities enables potential viscosupplementation for clinical application. Full article

(This article belongs to the Special Issue Marine Oligosaccharides and Polysaccharides)

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4233 KiB

Open AccessArticle

The Positive Correlation of the Enhanced Immune Response to PCV2 Subunit Vaccine by Conjugation of Chitosan Oligosaccharide with the Deacetylation Degree

by Guiqiang Zhang, Gong Cheng, Peiyuan Jia, Siming Jiao, Cui Feng, Tao Hu, Hongtao Liu and Yuguang Du

Mar. Drugs 2017, 15(8), 236; https://doi.org/10.3390/md15080236 - 26 Jul 2017

Cited by 19 | Viewed by 5139 | Correction

Abstract

Chitosan oligosaccharides (COS), the degraded products of chitosan, have been demonstrated to have versatile biological functions. In primary studies, it has displayed significant adjuvant effects when mixed with other vaccines. In this study, chitosan oligosaccharides with different deacetylation degrees were prepared and conjugated [...] Read more.

Chitosan oligosaccharides (COS), the degraded products of chitosan, have been demonstrated to have versatile biological functions. In primary studies, it has displayed significant adjuvant effects when mixed with other vaccines. In this study, chitosan oligosaccharides with different deacetylation degrees were prepared and conjugated to porcine circovirus type 2 (PCV2) subunit vaccine to enhance its immunogenicity. The vaccine conjugates were designed by the covalent linkage of COSs to PCV2 molecules and administered to BALB/c mice three times at two-week intervals. The results indicate that, as compared to the PCV2 group, COS–PCV2 conjugates remarkably enhanced both humoral and cellular immunity against PCV2 by promoting lymphocyte proliferation and initiating a mixed T-helper 1 (Th1)/T-helper 2 (Th2) response, including raised levels of PCV2-specific antibodies and an increased production of inflammatory cytokines. Noticeably, with the increasing deacetylation degree, the stronger immune responses to PCV2 were observed in the groups with COS-PCV2 vaccination. In comparison with NACOS (chitin oligosaccharides)–PCV2 and LCOS (chitosan oligosaccharides with low deacetylation degree)–PCV2, HCOS (chitosan oligosaccharides with high deacetylation degree)–PCV2 showed the highest adjuvant effect, even comparable to that of PCV2/ISA206 (a commercialized adjuvant) group. In summary, COS conjugation might be a viable strategy to enhance the immune response to PCV2 subunit vaccine, and the adjuvant effect was positively correlated with the deacetylation degree of COS. Full article

(This article belongs to the Special Issue Marine Oligosaccharides and Polysaccharides)

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3105 KiB

Open AccessArticle

The Deep-Sea Polyextremophile Halobacteroides lacunaris TB21 Rough-Type LPS: Structure and Inhibitory Activity towards Toxic LPS

by Flaviana Di Lorenzo, Angelo Palmigiano, Ida Paciello, Mateusz Pallach, Domenico Garozzo, Maria-Lina Bernardini, Violetta La Cono, Michail M. Yakimov, Antonio Molinaro and Alba Silipo

Mar. Drugs 2017, 15(7), 201; https://doi.org/10.3390/md15070201 - 27 Jun 2017

Cited by 23 | Viewed by 5663

Abstract

The structural characterization of the lipopolysaccharide (LPS) from extremophiles has important implications in several biomedical and therapeutic applications. The polyextremophile Gram-negative bacterium Halobacteroides lacunaris TB21, isolated from one of the most extreme habitats on our planet, the deep-sea hypersaline anoxic basin Thetis, [...] Read more.

The structural characterization of the lipopolysaccharide (LPS) from extremophiles has important implications in several biomedical and therapeutic applications. The polyextremophile Gram-negative bacterium Halobacteroides lacunaris TB21, isolated from one of the most extreme habitats on our planet, the deep-sea hypersaline anoxic basin Thetis, represents a fascinating microorganism to investigate in terms of its LPS component. Here we report the elucidation of the full structure of the R-type LPS isolated from H. lacunaris TB21 that was attained through a multi-technique approach comprising chemical analyses, NMR spectroscopy, and Matrix-Assisted Laser Desorption Ionization (MALDI) mass spectrometry. Furthermore, cellular immunology studies were executed on the pure R-LPS revealing a very interesting effect on human innate immunity as an inhibitor of the toxic Escherichia coli LPS. Full article

(This article belongs to the Special Issue Marine Oligosaccharides and Polysaccharides)

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2513 KiB

Open AccessArticle

Induction of p53-Independent Apoptosis and G1 Cell Cycle Arrest by Fucoidan in HCT116 Human Colorectal Carcinoma Cells

by Hye Young Park, Shin-Hyung Park, Jin-Woo Jeong, Dahye Yoon, Min Ho Han, Dae-Sung Lee, Grace Choi, Mi-Jin Yim, Jeong Min Lee, Do-Hyung Kim, Gi-Young Kim, Il-Whan Choi, Suhkmann Kim, Heui-Soo Kim, Hee-Jae Cha and Yung Hyun Choi

Mar. Drugs 2017, 15(6), 154; https://doi.org/10.3390/md15060154 - 30 May 2017

Cited by 64 | Viewed by 8857

Abstract

It is well known that fucoidan, a natural sulfated polysaccharide present in various brown algae, mediates anticancer effects through the induction of cell cycle arrest and apoptosis. Nevertheless, the role of tumor suppressor p53 in the mechanism action of fucoidan remains unclear. Here, [...] Read more.

It is well known that fucoidan, a natural sulfated polysaccharide present in various brown algae, mediates anticancer effects through the induction of cell cycle arrest and apoptosis. Nevertheless, the role of tumor suppressor p53 in the mechanism action of fucoidan remains unclear. Here, we investigated the anticancer effect of fucoidan on two p53 isogenic HCT116 (p53+/+ and p53−/−) cell lines. Our results showed that inhibition of cell viability, induction of apoptosis and DNA damage by treatment with fucoidan were similar in two cell lines. Flow cytometric analysis revealed that fucoidan resulted in G1 arrest in the cell cycle progression, which correlated with the inhibition of phosphorylation of retinoblastoma protein (pRB) and concomitant association of pRB with the transcription factor E2Fs. Furthermore, treatment with fucoidan obviously upregulated the expression of cyclin-dependent kinase (CDK) inhibitors, such as p21WAF1/CIP1 and p27KIP1, which was paralleled by an enhanced binding with CDK2 and CDK4. These events also commonly occurred in both cell lines, suggesting that fucoidan triggered G1 arrest and apoptosis in HCT116 cells by a p53-independent mechanism. Thus, given that most tumors exhibit functional p53 inactivation, fucoidan could be a possible therapeutic option for cancer treatment regardless of the p53 status. Full article

(This article belongs to the Special Issue Marine Oligosaccharides and Polysaccharides)

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Review

Jump to: Research, Other

34 pages, 3878 KiB

Open AccessReview

Exopolysaccharides from Marine and Marine Extremophilic Bacteria: Structures, Properties, Ecological Roles and Applications

by Angela Casillo, Rosa Lanzetta, Michelangelo Parrilli and Maria Michela Corsaro

Mar. Drugs 2018, 16(2), 69; https://doi.org/10.3390/md16020069 - 20 Feb 2018

Cited by 177 | Viewed by 14716

Abstract

The marine environment is the largest aquatic ecosystem on Earth and it harbours microorganisms responsible for more than 50% of total biomass of prokaryotes in the world. All these microorganisms produce extracellular polymers that constitute a substantial part of the dissolved organic carbon, [...] Read more.

The marine environment is the largest aquatic ecosystem on Earth and it harbours microorganisms responsible for more than 50% of total biomass of prokaryotes in the world. All these microorganisms produce extracellular polymers that constitute a substantial part of the dissolved organic carbon, often in the form of exopolysaccharides (EPS). In addition, the production of these polymers is often correlated to the establishment of the biofilm growth mode, during which they are important matrix components. Their functions include adhesion and colonization of surfaces, protection of the bacterial cells and support for biochemical interactions between the bacteria and the surrounding environment. The aim of this review is to present a summary of the status of the research about the structures of exopolysaccharides from marine bacteria, including capsular, medium released and biofilm embedded polysaccharides. Moreover, ecological roles of these polymers, especially for those isolated from extreme ecological niches (deep-sea hydrothermal vents, polar regions, hypersaline ponds, etc.), are reported. Finally, relationships between the structure and the function of the exopolysaccharides are discussed. Full article

(This article belongs to the Special Issue Marine Oligosaccharides and Polysaccharides)

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6396 KiB

Open AccessReview

Recent Advances in Marine Algae Polysaccharides: Isolation, Structure, and Activities

by Shu-Ying Xu, Xuesong Huang and Kit-Leong Cheong

Mar. Drugs 2017, 15(12), 388; https://doi.org/10.3390/md15120388 - 13 Dec 2017

Cited by 324 | Viewed by 22236

Abstract

Marine algae have attracted a great deal of interest as excellent sources of nutrients. Polysaccharides are the main components in marine algae, hence a great deal of attention has been directed at isolation and characterization of marine algae polysaccharides because of their numerous [...] Read more.

Marine algae have attracted a great deal of interest as excellent sources of nutrients. Polysaccharides are the main components in marine algae, hence a great deal of attention has been directed at isolation and characterization of marine algae polysaccharides because of their numerous health benefits. In this review, extraction and purification approaches and chemico-physical properties of marine algae polysaccharides (MAPs) are summarized. The biological activities, which include immunomodulatory, antitumor, antiviral, antioxidant, and hypolipidemic, are also discussed. Additionally, structure-function relationships are analyzed and summarized. MAPs’ biological activities are closely correlated with their monosaccharide composition, molecular weights, linkage types, and chain conformation. In order to promote further exploitation and utilization of polysaccharides from marine algae for functional food and pharmaceutical areas, high efficiency, and low-cost polysaccharide extraction and purification methods, quality control, structure-function activity relationships, and specific mechanisms of MAPs activation need to be extensively investigated. Full article

(This article belongs to the Special Issue Marine Oligosaccharides and Polysaccharides)

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