Sulfated Fucans Research Articles

Interference of an algal nutritional supplement with a urinary metabolic screening test for glycosaminoglycans in a dog suspected to have a storage disease

The finding of excess urinary glycosaminoglycans (GAG) is the first step in the laboratory diagnosis of mucopolysaccharidosis (MPS). Urinary screening tests are based upon the binding of GAG to dimethylmethylene blue. Alternatively, paper spot tests using toluidine blue are used in human and veterinary laboratory medicine. Positive samples undergo GAG isolation for subsequent characterization. Here, we describe a 3-year-old English Cocker Spaniel with a positive urinary GAG test, but without other clinical signs of MPS. Urine samples were strongly positive with the dimethylmethylene blue test, and isolated GAG subjected to electrophoresis on cellulose acetate revealed a band co-migrating with dermatan sulfate. However, the isolated GAG were resistant to digestion with chondroitinase ABC, suggesting that the band did not represent dermatan sulfate. This was confirmed by mobility of the isolated GAG different from dermatan sulfate on agarose gel electrophoresis. MPS types VI and VII were excluded by enzyme assay. To test the hypothesis of a nutritional source, a healthy control dog was fed the same dog food as the index case. His urine showed a comparable abnormal GAG screening test and electrophoretic pattern. In addition, the analysis of an algal supplement present in the administered dog food showed a similar electrophoretic GAG pattern. The Cocker Spaniel was not available for further testing after withdrawal of the supplement. Algae contain highly sulfated fucans and galactans, and it appears that commercial dog food containing such algal, and possibly other, supplements can give rise to false-positive urinary MPS screening tests.

Comparison of physicochemical characteristics and anticoagulant activities of polysaccharides from three sea cucumbers.

In order to search for sulfated polysaccharides in different invertebrate connective tissues and to examine their biological activities, we have isolated three types of polysaccharides from the body wall of the three sea cucumbers Holothuria edulis, Apostichopus japonicas and Holothuria nobilis. The physicochemical properties and anticoagulant activities of these polysaccharides were examined and compared. The chemical composition analysis and nuclear magnetic resonance (NMR) analysis indicate that two types of polysaccharides, sulfated fucan and fucosylated chondroitin sulfate (FuCS), were found in all of the three species and in addition a neutral glycan was observed in H. edulis. The neutral α-glucan was firstly obtained from sea cucumber. The same type of polysaccharides from different species of sea cucumbers have similar physicochemical properties and anticoagulant activities, but those of different types of glycans are significantly different, possibly due to their different monosaccharide compositions, electric charges and average molecular weights. The FuCSs have stronger anticoagulant activities than the sulfated fucans, although the molecular sizes of the FuCSs are lower than those of the sulfated fucans, whereas the neutral glucan has no activity, as expected from the absence of sulfate. Thus, anticoagulant activities of the different type of polysaccharides are likely to relate to monosaccharide composition and sulfate content. Preliminary analysis suggests that the sulfation patterns of the FuCSs may result in the difference in anticoagulant activities. Our data could help elucidate the structure-activity relationship of the sea cucumber polysaccharides.

Current Status of Fucanomics and Galactanomics in Drug Discovery and Glycomics

Although many biomedical applications for sulfated fucans and galactans have been discovered over the past two decades, only in inflammation, hemostasis, cancer, and vascular biology have their mechanisms of action satisfactorily elucidated to a real contribution in drug development. Moreover, advanced structure-function relationships have been achieved only for the anticoagulant and antithrombotic activities, in which glycans of well-defined structures have been assayed. Here, the current status, and the remaining challenges of fucanomics and galactanomics in drug discovery and in glycomics are briefly discussed.

Structural analysis of sulfated fucan from Saccharina japonica by electrospray ionization tandem mass spectrometry

Desulfation of a fucoidan from Saccharina japonica by treatment with DMSO–MeOH resulted in partial degradation of polymeric molecules by methanolysis giving rise to a mixture of neutral, monosulfated, and disulfated fucooligosaccharides in the form of methyl glycosides. These oligomeric fragments were characterized by ESI-MS and ESI-CID-MS/MS. It was found that oligosaccharide structures coincided with the polysaccharide backbone built up mainly of (1→3)-linked fucose residues sulfated at positions 4 and 2.

Antiproliferative Activity of Fucan Nanogel

Sulfated fucans comprise families of polydisperse natural polysaccharides based on sulfated L-fucose. Our aim was to investigate whether fucan nanogel induces cell-specific responses. To that end, a non toxic fucan extracted from Spatoglossum schröederi was chemically modified by grafting hexadecylamine to the polymer hydrophilic backbone. The resulting modified material (SNFuc) formed nanosized particles. The degree of substitution with hydrophobic chains was close to 100%, as estimated by elemental analysis. SNFfuc in aqueous media had a mean diameter of 123 nm and zeta potential of −38.3 ± 0.74 mV, as measured by dynamic light scattering. Nanoparticles conserved their size for up to 70 days. SNFuc cytotoxicity was determined using the MTT assay after culturing different cell lines for 24 h. Tumor-cell (HepG2, 786, H-S5) proliferation was inhibited by 2.0%–43.7% at nanogel concentrations of 0.05–0.5 mg/mL and rabbit aorta endothelial cells (RAEC) non-tumor cell line proliferation displayed inhibition of 8.0%–22.0%. On the other hand, nanogel improved Chinese hamster ovary (CHO) and monocyte macrophage cell (RAW) non-tumor cell line proliferation in the same concentration range. The antiproliferative effect against tumor cells was also confirmed using the BrdU test. Flow cytometric analysis revealed that the fucan nanogel inhibited 786 cell proliferation through caspase and caspase-independent mechanisms. In addition, SNFuc blocks 786 cell passages in the S and G2-M phases of the cell cycle.

Structure versus anticoagulant and antithrombotic actions of marine sulfated polysaccharides

Marine sulfated polysaccharides (MSP), such as sulfated fucans (SF), sulfated galactans (SG) and glycosaminoglycans (GAG) isolated from either algae or invertebrate animals, are highly anionic polysaccharides capable of interacting with certain cationic proteins, such as (co)-factors of the coagulation cascade during clotting-inhibition processes. These molecular complexes between MSP and coagulation-related proteins might, at first glance, be assumed to be driven mostly by electrostatic interactions. However, a systematic comparison using several novel sulfated polysaccharides composed of repetitive oligosaccharides with clear sulfation patterns has shown that these molecular interactions are regulated essentially by the stereochemistry of the glycans (which depends on a conjunction of anomericity, monosaccharide, conformational preference, and glycosylation and sulfation sites), rather than just a simple consequence of their negative charge density (mainly the number of sulfate groups). Here, we present an overview of the structure-function relationships of MSP, correlating their structures with their potential anticoagulant and antithrombotic actions, since pathologies related to the cardiovascular system are one of the major causes of illness and mortality in the world.

Fucanomics and Galactanomics: Marine Distribution, Medicinal Impact, Conceptions, and Challenges

Glycomics turned out to be a very extensive project where its subdivision is consequently emerging. This is seen by the growing number of terminologies used to define subprojects concerning particular classes of bioactive carbohydrates. Sulfated fucans (SFs) and sulfated galactans (SGs) are relatively new classes of sulfated polysaccharides (SPs) that occur mostly in marine organisms, and exhibit a broad range of medicinal effects. Their structures are taxonomically dependent, and their therapeutic actions include benefits in inflammation, coagulation, thrombosis, angiogenesis, cancer, oxidation, and infections. Some red algae, marine angiosperm and invertebrates express SPs of unique structures composed of regular repeating oligomeric units of well-defined sulfation patterns. This fine pattern of structural regularity is quite rare among any naturally occurring long SPs, and enables accurate structure-biofunction correlations. Seeing that, fucanomics and galactanomics may comprise distinguished glycomics subprojects. We hereby discuss the relevance that justifies the international recognition of these subprojects in the current glycomics age associated with the beneficial outcomes that these glycans may offer in drug development.

Sequence determination and anticoagulant and antithrombotic activities of a novel sulfated fucan isolated from the sea cucumber Isostichopus badionotus

BackgroundThe aim is to analyze the structure, anticoagulant and antithrombotic activities of a sulfated fucan isolated from sea cucumber Isostichopus badionotus (fucan-Ib). MethodsFucan-Ib was hydrolyzed under mild acid conditions. The oligosaccharide fragments were fractionated by gel-filtration chromatography and the structures were determined by negative-ion electrospray tandem mass spectrometry with collision-induced dissociation and two-dimensional NMR. Anticoagulant activities were measured by activated partial thromboplastin, thrombin and prothrombin times, and by in vitro inhibition experiments with factors IIa and Xa. Antithrombotic activities were determined in vitro by measuring the length and weight of the thrombus generated. ResultThe linear polysaccharide sequence of fucan-Ib was deduced from the structures of its oligosaccharide fragments produced by acid hydrolysis. Under mild conditions, the glycosidic bonds between the non-sulfated and 2,4-O-disulfated fucose residues were selectively cleaved and highly ordered oligosaccharide fragments with a tetrasaccharide repeating unit [→3Fuc(2S,4S)α1→3Fuc(2S)α1→3Fuc(2S)α1→3Fucα1→]n were obtained. In in vitro assays fucan-Ib showed good anticoagulant and antithrombotic activities compared with heparin and the fucosylated chondroitin sulfate isolated from the same source (fCS-Ib). The two polysaccharides, fucan-Ib and fCS-Ib, differ in the mechanism of action; the former exhibited activity mainly by potentiation of antithrombin acted on thrombin and factor Xa whereas the latter mainly through heparin cofactor II. ConclusionFucan-Ib has a well defined structure with tetrasaccharide tandem repeats and good anticoagulant and antithrombotic activities. General importanceFucan-Ib has a well defined structure and can be readily quality-controlled, and therefore has potential therapeutic value as an affective antithrombotic drug with low risk of bleeding.

Properties of polysaccharides in several seaweeds from Atlantic Canada and their potential anti-influenza viral activities

To explore the polysaccharides from selected seaweeds of Atlantic Canada and to evaluate their potential anti-influenza virus activities, polysaccharides were isolated from several Atlantic Canadian seaweeds, including three red algae (Polysiphonia lanosa, Furcellaria lumbricalis, and Palmaria palmata), two brown algae (Ascophyllum nodosum and Fucus vesiculosus), and one green alga (Ulva lactuca) by sequential extraction with cold water, hot water, and alkali solutions. These polysaccharides were analyzed for monosaccharide composition and other general chemical properties, and they were evaluated for anti-influenza virus activities. Total sugar contents in these polysaccharides ranged from 15.4% (in U. lactuca) to 91.4% (in F. lumbricalis); sulfation level was as high as 17.6% in a polysaccharide from U. lactuca, whereas it could not be detected in an alikali-extract from P. palmaria. For polysaccharides from red seaweeds, the main sugar units were sulfated galactans (agar or carrageenan) for P. lanosa, F. lumbricalis, and xylans for P. palmata. In brown seaweeds, the polysaccharides largely contained sulfated fucans, whereas the polysaccharides in green seaweed were mainly composed of heteroglycuronans. Screening for antiviral activity against influenza A/PR/8/34 (H1N1) virus revealed that brown algal polysaccharides were particularly effective. Seaweeds from Atlantic Canada are a good source of marine polysaccharides with potential antiviral properties.

Sulfated fucans extracted from algae Padina gymnospora have anti-inflammatory effect

Sulfated polysaccharides were extracted with acetone from brown algae Padina gymnospora. The fraction precipitated with 1.5 volumes of acetone (F1.5) purified in Sephadex G-75 was characterized by infrared and nuclear magnetic resonance of 13C and 1H, through which the presence of sulfate groups on the C4 of α-L-fucose could be observed. This polysaccharide showed that an MW of 25,000 Da was effective in reducing leukocyte influx into the peritoneal cavity in mice at 10 mg/kg and 25 mg/kg body weight, causing a decrease of 60 and 39%, respectively. In the present study, it was observed that this fucan has anti-inflammatory properties but no cytotoxic action, indicating its potential use in the pharmaceutical industry.

Fucanome and Galactanome: Marine Glycomics Contribution

Following the genome, transcriptome and proteome, the glycome has currently launched in biology bringing apparently more challenges than the first projects. The long major conception of carbohydrates as just energetically involved class of biomolecules has fallen apart as innumerable essential biological actions have been raised, impossible to be enlisted all together at once. Such actions involve not only vital roles in cell and physiology but within a different context they also include potent therapeutic actions in coagulation, thrombosis, inflammation, virosis, pathogenesis, tumorigenesis, metastasis and angiogenesis. Glycomics is so extensive project that subdivision is necessary for its progress. Specific segments of research have been created about particular bioactive sugar classes such as sialome for sialic acids, and heparanomics for heparan bioactive domains. Fucanome and galactanome must be also included in the recent glycomics age with respect to the relatively new class of marine fucose- or galactose-composing polysaccharides named sulfated fucans and sulfated galactans. These glycans are very biologically relevant since they show potent pharmacological properties in many of the above-mentioned systems; besides in sea-urchins they are responsible to control a very rare case of carbohydrate-mediated cell signaling event, the acrosome reaction. The structure of these glycans is very restricted to phyla or species of occurrence. Among all marine organisms, only invertebrates and red algae have been known so far to express high molecular weight polymers composed of well-defined structures. These structural features are unique and very rare among any bioactive polysaccharide ever studied. This would make fucanome and galactanome differential glycomics subprojects in terms of structure and phylogeny. This paper not only brings out novel segments and their respective contribution to glycomics but also highlights the great relevance of pharmacological effects of these new glycans in the current glycome era.

Fucose-Containing Sulfated Polysaccharides from Brown Seaweeds Inhibit Proliferation of Melanoma Cells and Induce Apoptosis by Activation of Caspase-3 in Vitro

Fucose-containing sulfated polysaccharides (FCSPs) extracted from seaweeds, especially brown macro-algae, are known to possess essential bioactive properties, notably growth inhibitory effects on tumor cells. In this work, we conducted a series of in vitro studies to examine the influence of FCSPs products from Sargassum henslowianum C. Agardh (FSAR) and Fucus vesiculosus (FVES), respectively, on proliferation of melanoma B16 cells and to investigate the underlying apoptosis promoting mechanisms. Cell viability analysis showed that both FCSPs products, i.e., FSAR and FVES, decreased the proliferation of the melanoma cells in a dose-response fashion, with FSAR being more potent at lower dosages, and FVES being relatively more anti-proliferative than FSAR at higher dosages. Flow cytometric analysis by Annexin V staining of the melanoma cells exposed to the FCSPs products confirmed that both FSAR and FVES induced apoptosis. The FCSPs-induced apoptosis was evidenced by loss of plasma membrane asymmetry and translocation of the cell membrane phospholipids and was accompanied by the activation of caspase-3. The FCSPs bioactivity is proposed to be attributable to distinct structural features of the FCSPs, particularly the presence of sulfated galactofucans (notably in S. henslowianum) and sulfated fucans (notably in F. vesiculosus). This study thus indicates that unfractionated FCSPs may exert bioactive effects on skin cancer cells via induction of apoptosis through cascades of reactions that involve activation of caspase-3.

Mild acid hydrolysis of fucoidan: characterization by electrophoresis and FT-Raman spectroscopy

Along with proteins, lipids, water and minerals, polysaccharides are the main chemical compounds of which macroalgae are built. Among the chemical compounds now widely examined is fucoidan (fucan, fucosan, sulfate fucan or sulfated fucan), a fucose-containing sulfated polysaccharide. Fucoidans isolated from different species have been extensively studied because of their varied biological properties, including anticoagulant and antitumor effects. Methodology based on mild acid hydrolysis can be used as an efficient tool to study the relationship between molecular weight of the sulfated polysaccharides and their biological activities. Anticancer activity of fucoidans can be significantly enhanced by lowering their molecular weight only when they are depolymerized under mild conditions. In this study, fucoidan was identified during extraction with H2SO4 and HCl; its presence was confirmed by FT-Raman spectroscopy in aqueous solution. In particular, shifts at 840cm−1 were analysed, which are due to the presence of sulfate at the axial C-4 position, as were the shifts at about 811–809cm−1, for which the sulfated fucoidan is responsible. Shifts of electrophoretic bands of fucoidan resulting from mild acid hydrolysis in H2SO4 and HCl were also analysed. The analytical procedure was developed using apparatus for cellulose acetate membrane electrophoresis and this was supplemented by semi-quantitative analysis.

Sulfated fucan from marine alga inhibits HeLa cells infection by HTLV-1 free particles: semi-quantitative analysis

A sulfated fucan from Laminaria abyssalis marine alga prevented the interaction of HTLV-1 particles, purified from the MT-2 cell line, with HeLa cells. The infection obtained using a concentrated virus suspension was detected only by amplification of the newly synthesized HTLV-1 proviral cDNA by the nested-polymerase chain reaction (PCR). The sulfated polysaccharide was not toxic to the cells at a concentration of 100 µg/mL and prevented infection by the viral particles when added to the cell monolayers. The proviral cDNA was only detected when the sulfated polysaccharide was added to the cells three hours post-infection, indicating that the inhibitory activity occurred in the initial stages of virus-cell interaction. Our results demonstrate, for the first time, the ability of a sulfated fucan from marine algae to inhibit virus transmission through free virus particles.

Inhibitory effects of fucan sulfates on enzymatic hydrolysis of starch

The effect of fucoidan and its oversulfated derivative on starch digestibility was investigated by determining the enzymatic reaction kinetics and their inhibitory activity against α-amylase and amyloglucosidase. After the α-amylase hydrolysis, the produced reducing sugars of the buckwheat starch (BW, 2.0–3.0 g/100 mL) and those of the blends of BW with low levels of native fucoidan (NF, 0.5–1.0 g/100 mL) and oversulfated fucoidan (OSF, 0.5–1.0 g/100 mL) were in the range of 440–450 mg/g starch. The addition of NF and OSF did not significantly influence the α-amylolysis. The hydrolysis of the starch and the fucoidan blends using both α-amylase and amyloglucosidase was decreased to 12% by the addition of 1.0 g/100 mL OSF, while only 5% reduction of the starch hydrolysis by 1.0 g/100 mL NF. The inhibitory activity of NF on amyloglucosidase was negligible, but that of OSF on amyloglucosidase was considerable up to 21.2% at the concentration of 10 mg/mL with non-competitive inhibition mechanism. It was suggested that the substantial reduction of starch hydrolysis by the addition of OSF may be caused by a direct inhibition of amyloglucosidase activity, implying a possible application of OSF as an enzyme inhibitor.

The cell wall polysaccharide metabolism of the brown alga Ectocarpus siliculosus. Insights into the evolution of extracellular matrix polysaccharides in Eukaryotes.

• Brown algal cell walls share some components with plants (cellulose) and animals (sulfated fucans), but they also contain some unique polysaccharides (alginates). Analysis of the Ectocarpus genome provides a unique opportunity to decipher the molecular bases of these crucial metabolisms. • An extensive bioinformatic census of the enzymes potentially involved in the biogenesis and remodeling of cellulose, alginate and fucans was performed, and completed by phylogenetic analyses of key enzymes. • The routes for the biosynthesis of cellulose, alginates and sulfated fucans were reconstructed. Surprisingly, known families of cellulases, expansins and alginate lyases are absent in Ectocarpus, suggesting the existence of novel mechanisms and/or proteins for cell wall expansion in brown algae. • Altogether, our data depict a complex evolutionary history for the main components of brown algal cell walls. Cellulose synthesis was inherited from the ancestral red algal endosymbiont, whereas the terminal steps for alginate biosynthesis were acquired by horizontal gene transfer from an Actinobacterium. This horizontal gene transfer event also contributed genes for hemicellulose biosynthesis. By contrast, the biosynthetic route for sulfated fucans is an ancestral pathway, conserved with animals. These findings shine a new light on the origin and evolution of cell wall polysaccharides in other Eukaryotes.

Structural analysis of a highly sulfated fucan from the brown alga Laminaria cichorioides by tandem MALDI and ESI mass spectrometry

Water-soluble polysaccharide fractions were extracted from the brown alga Laminaria cichorioides. Samples were collected monthly from May to October in Troitsa Bay (Japan Sea, Russia). Analysis showed that the content and monosaccharide composition of the fractions changed with the collection season. Fucoidan was isolated and purified from the most fucose-rich fraction, collected in July, and subjected to autohydrolysis to obtain fucooligosaccharides, suitable for mass-spectrometric analysis. Both ESIMS and MALDI-TOFMS analyses show that multisulfated (up to 3) fucooligosaccharides with polymerization degree n from 2 to 5, including mono- and disulfated-fucose residues, were the major products of autohydrolysis. The structural features of the fucooligosaccharides and their alditol derivatives were elucidated by tandem MALDI-TOFMS and ESIMS. The results obtained allowed us to conclude that fragments of the fucoidan, collected in July, were predominantly linked with a (1→3)-type of linkage and that sulfate groups occupied mostly C-2 or C-2/C-4 of the α- l-fucose residues.

Further studies on the composition and structure of a fucoidan preparation from the brown alga Saccharina latissima

The polysaccharide composition of a fucoidan preparation isolated from the brown alga Saccharina latissima (formerly Laminaria saccharina) was reinvestigated. The preparation was fractionated by anion-exchange chromatography, and the fractions obtained were analyzed by chemical methods combined with NMR spectroscopy. Several 2D procedures, including HSQC, HMQC-TOCSY, and HMQC-NOESY, were used to obtain reliable structural information from the complex spectra, and the signal assignments were additionally confirmed by comparison with the literature spectra of the related polysaccharides and synthetic oligosaccharides. In accordance with the previous data, the main polysaccharide component was shown to be a fucan sulfate containing a backbone of 3-linked α- l-fucopyranose residues sulfated at C-4 and/or at C-2 and branched at C-2 by single sulfated α- l-fucopyranose residues. In addition, three other types of sulfated polysaccharide molecules were detected in the total fucoidan preparation: (i) a fucogalactan having a backbone of 6-linked β- d-galactopyranose residues branched mainly at C-4 and containing both terminal galactose and fucose residues; (ii) a fucoglucuronomannan having a backbone of alternating 4-linked β- d-glucopyranosyluronic acid and 2-linked α- d-mannopyranose residues with α- l-fucopyranose residues as single branches at C-3 of α- d-Man p; and (iii) a fucoglucuronan having a backbone of 3-linked β- d-glucopyranosyluronic acid residues with α- l-fucopyranose residues as single branches at C-4. Hence, even a single algal species may contain, at least in minor amounts, several sulfated polysaccharides differing in molecular structure. Partial resolution of these polysaccharides has been accomplished, but unambiguous evidence on their presence as separate entities was not obtained.

Effects of sulfated fucan, ascophyllan, from the brown Alga Ascophyllum nodosum on various cell lines: a comparative study on ascophyllan and fucoidan.

The effects of fucose-containing sulfated polysaccharides, ascophyllan and fucoidan, isolated from the brown alga Ascophyllum nodosum, on the growth of various cell lines (MDCK, Vero, PtK(1), CHO, HeLa, and XC) were investigated. In a colony formation assay, ascophyllan and fucoidan showed potent cytotoxic effects on Vero and XC cells, while other cell lines were relatively resistant to these polysaccharides. Almost no significant effects of these polysaccharides were observed in the cell lines tested using the Alamar blue cytotoxicity assay over 48 h with varying initial cell densities (2500-20,000 cells/well) in growth medium. Interestingly, a significant growth promoting effect of ascophyllan on MDCK cells was observed, whereas treatment with fucoidan showed growth suppressive effects on this cell line under the same experimental conditions. These results suggest that ascophyllan is distinguishable from fucoidan in terms of their bioactivities. This is the first report of the growth promoting effects of a sulfated fucan on a mammalian cell line under normal growth conditions.

Contrasting Correlation in the Inhibition Response of ADP-induced Platelet Aggregation and the Anti-coagulant Activities of Algal fucoidans Derived from Eisenia bicyclis and Undaria pinnatifida sporophylls (Mekabu)

Sulfated fucans are known to have both anti-thrombotic and anti-coagulant activities. In this study, the variation in platelet aggregation and anti-coagulant activities was investigated in vitro with regard to administered dose, molecular weight distribution, sulfate content, and sugar composition in two algal fucoidans from Eisenia bicyclis and Undaria pinnatifida sporophylls (Mekabu). The anti-coagulant activity largely correlated with sulfate content and with molecular weight distribution in a dose-dependent manner. However, both fucoidans demonstrated inhibitory responses to ADP-induced platelet aggregation in dose- and structure-dependent manners that contrasted with the anti-coagulant activity. Neither molecular weight distribution nor sulfate content greatly affected platelet-aggregation inhibition (PA-inhibition) by the fucoidan fractions, whereas anti-coagulant activity was sensitive to these structural factors. Interestingly, an E. bicyclis fucoidan fraction exhibited almost complete PA-inhibition at a treatment dose of 500 mg/mL while retaining weak anti-coagulant activity. In conclusion, these observations suggest that fucoidan may be a useful anti-thrombotic or anti-platelet agent in various arterial thrombotic disorders, including post-vascular intervention with controlled bleeding complications, due to its anti-coagulant modulating activity.