Identification of a highly sulfated fucoidan from sea cucumber Pearsonothuria graeffei with well-repeated tetrasaccharides units

Structural characterization of a distinct fucan sulfate from Pattalus mollis through an oligosaccharide mapping approach

The elucidation of the precise structure of fucan sulfate is essential for understanding the structure-activity relationship and promoting potential biomedical applications. In this work, the structure of a distinct fucan sulfate fraction V (PmFS in Ref 15 and FSV in Ref 16 → PFV) from Pattalus mollis was investigated using an oligosaccharide mapping approach. Six size-homogeneous fractions were purified from the mild acid hydrolyzed PFV and identified as fucitols, disaccharides and trisaccharides by 1D/2D NMR and MS analysis. Significantly, the sulfation pattern, glycosidic linkages, and sequences of all the oligosaccharides were unambiguously identified. The common 2-desulfation of the reducing end residue of the oligosaccharides was observed. Overall, the backbone of PFV was composed of L-Fuc2S (major) and L-Fuc3S (minor) linked by α1,4 glycosidic bonds. Importantly, the branches contain both monosaccharide and disaccharide linked to the backbone by α1,3 glycosidic linkages. Thus, the tentative structure of natural PFV was shown to be {-(R-α1,3)-L-Fuc2S-α1,4-(L-Fuc2S/3S-α1,4)x-}n, where R is L-Fuc(2S)4S-α1,3/4-L-Fuc4S(0S)- or L-Fuc(2S)4S-. Our results provide insight into the heterogeneous structure of the fucan sulfate found in sea cucumbers. Additionally, PFV and its fractions showed strong anticoagulant and anti-iXase activities, which may be related to the distinct structure of PFV.

Sulfated polysaccharides in sea cucumbers and their biological properties: A review

Sea cucumbers contain a wide range of biomolecules, including sulfated polysaccharides (SPs), with immense therapeutic and nutraceutical potential. SPs in sea cucumbers are mainly fucosylated chondroitin sulfate (FCS) and fucan sulfate (FS) which exhibit a series of pharmacological effects, including anticoagulant activity, in several biological systems. FCS is a structurally distinct glycosaminoglycan in the sea cucumber body wall, and its biological properties mainly depend on the degree of sulfation, position of sulfate group, molecular weight, and distribution of branches along the backbone. So far, FCS and FS have been recognized for their antithrombotic, anti-inflammatory, anticancer, antidiabetic, anti-hyperlipidemic, anti-obesity, and antioxidant potential. However, the functions of these SPs are mainly dependent on the species, origins, harvesting season, and extraction methods applied. This review focuses on the SPs of sea cucumbers and how their structural diversities affect various biological activities. In addition, the mechanism of actions of SPs, chemical structures, factors affecting their bioactivities, and their extraction methods are also discussed.

Potential Application of Marine Fucosyl-Polysaccharides in Regulating Blood Glucose and Hyperglycemic Complications

Diabetes mellitus (DM) has become the world's third major disease after tumors and cardiovascular disease. With the exploitation of marine biological resources, the efficacy of using polysaccharides isolated from marine organisms in blood glucose regulation has received widespread attention. Some marine polysaccharides can reduce blood glucose by inhibiting digestive enzyme activity, eliminating insulin resistance, and regulating gut microbiota. These polysaccharides are mainly fucose-containing sulphated polysaccharides from algae and sea cucumbers. It follows that the hypoglycemic activity of marine fucosyl-polysaccharides is closely related to their structure, such as their sulfate group, monosaccharide composition, molecular weight and glycosidic bond type. However, the structure of marine fucosyl-polysaccharides and the mechanism of their hypoglycemic activity are not yet clear. Therefore, this review comprehensively covers the effects of marine fucosyl-polysaccharides sources, mechanisms and the structure-activity relationship on hypoglycemic activity. Moreover, the potential regulatory effects of fucosyl-polysaccharides on vascular complications caused by hyperglycemia are also summarized in this review. This review provides rationales for the activity study of marine fucosyl-polysaccharides and new insights into the high-value utilization of marine biological resources.

Sulfated fucan could serve as a species marker of sea cucumber with endo-1,3-fucanase as the essential tool

In the past few decades, sulfated fucan from sea cucumber had attracted considerable interest owing to its abundant physiological activities. Nevertheless, its potential for species discrimination had not been investigated. Herein, particular attention was given to sea cucumber Apostichopus japonicus, Acaudina molpadioides, Holothuria hilla, Holothuria tubulosa, Isostichopus badionotus and Thelenota ananas to examine the feasibility of sulfated fucan as a species marker of sea cucumber. The enzymatic fingerprint suggested that sulfated fucan exhibited significant interspecific discrepancy and intraspecific stability, which revealed that sulfated fucan could serve as the species marker of sea cucumber, by utilizing the overexpressed endo-1,3-fucanase Fun168A and the ultra-performance liquid chromatography-high resolution mass spectrum. Moreover, oligosaccharide profile of sulfated fucan was determined. The oligosaccharide profile combined with hierarchical clustering analysis and principal components analysis further confirmed that sulfated fucan could serve as a marker with a satisfying performance. Besides, load factor analysis showed that the minor structure of sulfated fucan also contributed to the sea cucumber discrimination, besides the major structure. The overexpressed fucanase played an indispensable role in the discrimination, due to its specificity and high activity. The study would lead to a new strategy for species discrimination of sea cucumber based on sulfated fucan.

Sea cucumber-derived compounds for treatment of dyslipidemia: A review

Dyslipidemias are disorders of plasma levels of lipids, such as elevated levels of total cholesterol and triglyceride, that are associated with various human diseases including cardiovascular disease (CVD) and non-alcoholic fatty liver disease (NAFLD). Statins are the first-line drugs for treatment of dyslipidemia. However, a substantial proportion of patients cannot reach the recommended LDL-c level even with the highest tolerated doses of statins, and there is no available drug specifically for NAFLD therapy. Sea cucumbers are one of the widely distributed invertebrates, and are an important resource of food and medicine. Sea cucumbers have many valuable nutrients including saponins, fatty acids, phospholipids, cerebrosides, sulfated polysaccharides, as well as proteins and peptides. In recent years, these natural products derived from sea cucumbers have attracted attentions for treatment of CVD and NAFLD because of their lipid-lowering effect and low toxicity. However, the hypolipidemic mechanisms of action and the structure-activity relationship of these bioactive components have not been well-documented in literature. This review article summarizes the signaling pathways and the potential structure-activity relationship of sea cucumber-derived bioactive compounds including saponins, lipids, carbohydrates as well as peptides and proteins. This article will provide information useful for the development of sea cucumber-derived lipid-lowering compounds as well as for investigation of hypolipidemic compounds that are derived from other natural resources.

Fucose-Rich Sulfated Polysaccharides from Two Vietnamese Sea Cucumbers Bohadschia argus and Holothuria (Theelothuria) spinifera: Structures and Anticoagulant Activity

Fucosylated chondroitin sulfates (FCSs) FCS-BA and FCS-HS, as well as fucan sulfates (FSs) FS-BA-AT and FS-HS-AT were isolated from the sea cucumbers Bohadschia argus and Holothuria (Theelothuria) spinifera, respectively. Purification of the polysaccharides was carried out by anion-exchange chromatography on DEAE-Sephacel column. Structural characterization of polysaccharides was performed in terms of monosaccharide and sulfate content, as well as using a series of non-destructive NMR spectroscopic methods. Both FCSs were shown to contain a chondroitin core [→3)-β-d-GalNAc-(1→4)-β-d-GlcA-(1→]_n bearing sulfated fucosyl branches at O-3 of every GlcA residue in the chain. These fucosyl residues were different in pattern of sulfation: FCS-BA contained Fuc2S4S, Fuc3S4S and Fuc4S at a ratio of 1:8:2, while FCS-HS contained these residues at a ratio of 2:2:1. Polysaccharides differed also in content of GalNAc4S6S and GalNAc4S units, the ratios being 14:1 for FCS-BA and 4:1 for FCS-HS. Both FCSs demonstrated significant anticoagulant activity in clotting time assay and potentiated inhibition of thrombin, but not of factor Xa. FS-BA-AT was shown to be a regular linear polymer of 4-linked α-L-fucopyranose 3-sulfate, the structure being confirmed by NMR spectra of desulfated polysaccharide. In spite of considerable sulfate content, FS-BA-AT was practically devoid of anticoagulant activity. FS-HS-AT cannot be purified completely from contamination of some FCS. Its structure was tentatively represented as a mixture of chains identical with FS-BA-AT and other chains built up of randomly sulfated alternating 4- and 3-linked α-L-fucopyranose residues.

A Fucan Sulfate with Pentasaccharide Repeating Units from the Sea Cucumber Holothuriafloridana and Its Anticoagulant Activity

A fucan sulfate (HfFS) was isolated from the sea cucumber Holothuriafloridana after proteolysis-alkaline treatment and purified with anion-exchange chromatography. The molecular weight (Mw) of HfFS was determined to be 443.4 kDa, and the sulfate content of HfFS was 30.4%. The structural analysis of the peroxidative depolymerized product (dHfFS-1) showed that the primary structure of HfFS was mainly composed of a distinct pentasaccharide repeating unit -[l-Fuc_2S4S-α(1,3)-l-Fuc-α(1,3)-Fuc-α(1,3)-l-Fuc_2S-α(1,3)-l-Fuc_2S-α(1,3)-]_n-. Then, the “bottom-up” strategy was employed to confirm the structure of HfFS, and a series of fucooligosaccharides (disaccharides, trisaccharides, and tetrasaccharides) were purified from the mild acid-hydrolyzed HfFS. The structures identified through 1D/2D NMR spectra showed that these fucooligosaccharides could be derivates from the pentasaccharide units, while the irregular sulfate substituent also exists in the units. Anticoagulant activity assays of native HfFS and its depolymerized products (dHf-1~dHf-6) in vitro suggested that HfFS exhibits potent APTT-prolonging activity and the potencies decreased with the reduction in molecular weights, and HfFS fragments (dHf-4~dHf-6) with Mw less than 11.5 kDa showed no significant anticoagulant effect. Overall, our study enriched the knowledge about the structural diversity of FSs in different sea cucumber species and their biological activities.

Oligosaccharide mapping analysis by HILIC-ESI-HCD-MS/MS for structural elucidation of fucoidan from sea cucumber Holothuria floridana

The elucidation of precise structure of fucoidan is essential for understanding their structure-function relationship and promoting the development of marine drugs. In this work, we firstly reported the oligosaccharide mapping of fucoidan from Holothuria floridana using a combination of hydrothermal depolymerization, hydrophilic interaction liquid chromatography (HILIC) coupled with electrospray mass spectrometry (ESI-FTMS) and high energy collision-induced dissociation (HCD-MS/MS) and 2D NMR analysis. With careful selection of fully deprotonated molecular ions of fucoidan oligosaccharides and their NaBD₄ reduced alditols, HILIC-ESI-HCD-MS/MS provided structurally relevant glycosidic product ions with no sulfate loss for definitive assignment of sequence and sulfation pattern of all the oligosaccharides and their isomers from dp2 to dp7 from hydrothermal depolymerization. The oligosaccharide mapping clarified the structure of fucoidan with various oligosaccharide domains with 2,4-di-O-sulfated and 2-O sulfated fucose residues.

Health effects of dietary sulfated polysaccharides from seafoods and their interaction with gut microbiota

Various dietary sulfated polysaccharides (SPs) have been isolated from seafoods, including edible seaweeds and marine animals, and their health effects such as antiobesity and anti-inflammatory activities have attracted remarkable interest. Sulfate groups have been shown to play important roles in the bioactivities of these polysaccharides. Recent in vitro and in vivo studies have suggested that the biological effects of dietary SPs are associated with the modulation of the gut microbiota. Dietary SPs could regulate the gut microbiota structure and, accordingly, affect the production of bioactive microbial metabolites. Because of their differential chemical structures, dietary SPs may specifically affect the growth of certain gut microbiota and associated metabolite production, which may contribute to variable health effects. This review summarizes the latest findings on the types and structural characteristics of SPs, the effects of different processing techniques on the structural characteristics and health effects of SPs, and the current understanding of the role of gut microbiota in the health effects of SPs. These findings might help in better understanding the mechanism of the health effects of SPs and provide a scientific basis for their application as functional food.

The Pros and Cons of Using Algal Polysaccharides as Prebiotics

Macroalgae stand out for their high content of dietary fiber (30–75%) that include soluble, sulfated (fucoidan, agaran, carrageenan, and ulvan) and non-sulfated (laminaran and alginate) polysaccharides. Many studies indicate that these compounds exert varied biological activities and health-promoting effects and for this reason, there is a growing interest for using them in food products. The aim of this review was to critically evaluate prebiotic properties of algal polysaccharides, i.e., their ability to exert biological activities by modulating the composition and/or diversity of gut microbiota (GM). Pre-clinical studies show that the non-sulfated alginate and laminaran are well-fermented by GM, promoting the formation of short chain fatty acids (SCFAs) including butyrate, and preventing that of harmful putrefactive compounds (NH₃, phenol, p-cresol, indole and H₂S). Alginate increases Bacteroides, Bifidobacterium, and Lactobacillus species while laminaran mostly stimulates Bacteroides sp. Results with sulfated polysaccharides are more questionable. Agarans are poorly fermentable but agarose-oligosaccharides exhibit an interesting prebiotic potential, increasing butyrate-producing bacteria and SCFAs. Though carrageenan-oligosaccharides are also fermented, their use is currently limited due to safety concerns. Regarding fucoidan, only one study reports SCFAs production, suggesting that it is poorly fermented. Its effect on GM does not indicate a clear pattern, making difficult to conclude whether it is beneficial or not. Notably, fucoidan impact on H₂S production has not been evaluated, though some studies report it increases sulfate-reducing bacteria. Ulvan is badly fermented by GM and some studies show that part of its sulfate is dissimilated to H₂S, which could affect colonic mitochondrial function. Accordingly, these results support the use of laminaran, alginate and agaro-oligosaccharides as prebiotics while more studies are necessary regarding that of fucoidan, carrageenan and ulvan. However, the realization of clinical trials is necessary to confirm such prebiotic properties in humans.

Advances in the Study of Marine Products with Lipid-Lowering Properties

With twice the number of cancer's deaths, cardiovascular diseases have become the leading cause of death worldwide. Atherosclerosis, in particular, is a progressive, chronic inflammatory cardiovascular disease caused by persistent damage to blood vessels due to elevated cholesterol levels and hyperlipidemia. This condition is characterized by an increase in serum cholesterol, triglycerides, and low-density lipoprotein, and a decrease in high-density lipoprotein. Although existing therapies with hypolipidemic effects can improve the living standards of patients with cardiovascular diseases, the drugs currently used in clinical practice have certain side effects, which insists on the need for the development of new types of drugs with lipid-lowering effects. Some marine-derived substances have proven hypolipidemic activities with fewer side effects and stand as a good alternative for drug development. Recently, there have been thousands of studies on substances with lipid-lowering properties of marine origin, and some are already implemented in clinical practice. Here, we summarize the active components of marine-derived products having a hypolipidemic effect. These active constituents according to their source are divided into algal, animal, plant and microbial and contribute to the development and utilization of marine medicinal products with hypolipidemic effects.

Sulfated fucan/fucosylated chondroitin sulfate-dominated polysaccharide fraction from low-edible-value sea cucumber ameliorates type 2 diabetes in rats: New prospects for sea cucumber polysaccharide based-hypoglycemic functional food

Sulfated fucan chondroitin sulfate-dominated polysaccharide fraction from low-edible-value sea cucumber may be a good alternative to high-edible-value sea cucumber-derived polysaccharide for application in hypoglycemic functional foods. To evaluate the potential effect of low-edible-value sea cucumber-derived polysaccharide fraction on type 2 diabetes (T2DM), two sulfated fucan/fucosylated chondroitin sulfate-dominated polysaccharide fractions screening from 10 global commercial low-edible-value sea cucumber species were investigated to identify their anti-diabetics efficacies using a high-fat diet and streptozotocin-induced T2DM rat model. Sulfated fucan-dominated polysaccharide fraction from Thelenota ananas and fucosylated chondroitin sulfate-dominated polysaccharide fraction from Cucumaria frondosa ameliorated hyperglycemia, restored hypertriglyceridemia and hypercholesterolemia, decreased inflammatory status and oxidative stress, protected against liver injury, as well as improved insulin resistance and promoted accumulation of hepatic glycogen by activating IRS/PI3K/AKT signaling and regulating GSK-3β gene expression in T2DM rats. The current findings provide an available strategy for the commercialization of sea cucumber polysaccharide based-hypoglycemic functional food.

Highly purified fucosylated chondroitin sulfate oligomers with selective intrinsic factor Xase complex inhibition

Fucosylated chondroitin sulfate (FCS) oligosaccharides of specific molecular weight have shown potent anticoagulant activities with selectivity towards intrinsic factor Xase complex. However, the preparation of FCS oligosaccharides by traditional methods requires multiple purification steps consuming large amounts of time and significant resources. The current study focuses on developing a method for the rapid preparation of FCS oligomers from sea cucumber Pearsonothuria graeffei having 6-18 saccharide residues. The key steps controlling molecular weight (Mw) and purity of these FCS oligomers were evaluated. Structural analysis showed the resulting FCS oligomers were primarily l-Fuc3,4diS-α1,3-d-GlcA-β1,3-(d-GalNAc4,6diS-β1,4-[l-Fuc3,4diS-α1,3-]d-GlcA-β1,3-)_nd-anTal-ol4,6diS (n = 1˜5) accompanied by partial de-fucosylation and/or de-sulfation. In vitro and in vivo experiments demonstrate that these FCS oligomers selectively inhibit intrinsic factor Xase complex and exhibit remarkable antithrombotic activity without hemorrhagic and hypotension side effects. This method is suitable for large-scale preparation of FCS oligosaccharides as clinical anticoagulants.

Anticoagulant Polyethylene Terephthalate Surface by Plasma-Mediated Fucoidan Immobilization

Biomaterial-based blood clot formation is one of the biggest drawbacks of blood-contacting devices. To avoid blood clot formation, their surface must be tailored to increase hemocompatibility. Most synthetic polymeric biomaterials are inert and lack bonding sites for chemical agents to bond or tailor to the surface. In this study, polyethylene terephthalate was subjected to direct current air plasma treatment to enhance its surface energy and to bring oxidative functional binding sites. Marine-sourced anticoagulant sulphated polysaccharide fucoidan from Fucus vesiculosus was then immobilized onto the treated polyethylene terephthalate (PET) surface at different pH values to optimize chemical bonding behavior and therefore anticoagulant performance. Surface properties of samples were monitored using the water contact angle; chemical analyses were performed by FTIR and X-ray photoelectron spectroscopy (XPS) and their anticoagulant activity was tested by means of prothrombin time, activated partial thromboplastin time and thrombin time. On each of the fucoidan-immobilized surfaces, anticoagulation activity was performed by extending the thrombin time threshold and their pH 5 counterpart performed the best result compared to others.

Structural characterization and anti-thrombotic properties of fucoidan from Nemacystus decipiens

The sulfated polysaccharide NP2 was isolated and purified from Nemacystus decipiens, the structure and antithrombotic activity of NP2 was further studied. NP2 was composed of fucose, glucuronic acid, galactose and xylose at molar ratios of 76.3:20.5:1.5:1.7. ES-CID-MS/MS results showed that NP2 had a backbone of α (1 → 3)-linked fucose and a branch was composed of Fuc-(2 → 1)-GlcA, which was agree with the results of NMR and methylation analysis. The results also show that the sulfate groups were substituted at the C2 or C4 positions of the fucose residues. In addition, analysis of the antithrombotic activity results indicated that NP2 can increase the percentage of t-PA/PAI-1, thereby suggesting that NP2 has high fibrinolytic activity and should be explored as a novel antithrombotic agent.

Pectic oligosaccharides hydrolyzed from citrus canning processing water by Fenton reaction and their antiproliferation potentials

Citrus canning processing water contains a valuable and renewable source of biopolymers and bioactive compounds including pectic polysaccharides. Upgrading these processing wastes can not only alleviate environmental pollution but also add value to the commodity's production. In a previous study we recovered pectic polysaccharides from citrus canning processing water. In the present study, pectic polysaccharides recycled from citrus canning processing water was depolymerized by an optimized Fenton system. The hydrolyzate was fractionated via size-exclusion chromatography into six fractions: 500 Da < LMP1 < 3 kDa; 3 kDa < LMP2 < 5 kDa; 5 kDa < LMP3 < 12 kDa; 12 kDa < LMP4 < 25 kDa; 25 kDa < LMP5 < 100 kDa and LMP6 > 10 wDa. Structure analyses showed that LMP1 were homogalacturonans-enriched non-esterified polysaccharides. While LMP2 contained both HG and rhamnogalacturonan-I (RG-I). Further antitumor assay showed that in comparison with the native pectic polysaccharide with moderate antitumor activity, both LMP1 and LMP2 possessed significant antitumor activity, while the inhibitory effect of LMP1 was higher than that of LMP2, suggesting that the biological properties of LMPs was influenced by structural characteristics, including molecular weight and monosaccharide composition.

Fucosylated chondroitin sulfate from Isostichopus badionotus alleviates metabolic syndromes and gut microbiota dysbiosis induced by high-fat and high-fructose diet

Fucosylated chondroitin sulfate from Isostichopus badionotus (fCS-Ib) is a kind of sulfated polysaccharides with well-repeated structure. In our former publications, fCS-Ib has been reported to be a functional food ingredient with hypoglycemic and antilipemic activities. However, there is no systematic study to investigate the effects of fCS-Ib on metabolic syndromes. In the present study, C57BL/6 mice fed on a high-fat and high sucrose diet (HFSD) for 6 weeks was used to cause metabolic syndromes. The final results showed that fCS-Ib alleviated obesity, hyperlipidemia, hyperglycemia, inflammation, liver steatosis, and adipocyte hypertrophy caused by HFSD. Meanwhile, fCS-Ib showed powerful effects on moderating gut microbiota dysbiosis in the HFSD-fed mice. Supplement of fCS-Ib could reduce ratio of Firmicutes to Bacteroidetes by decreasing abundance of Lachnospiraceae and Allobaculum while increasing abundance of Porphyromonadaceae, Barnesiella, and Bacteroides. Our results showed that fCS-Ib could be further developed as a potential pharmaceutical agent to prevent metabolic syndromes and gut microbiota dysbiosis.

Structure and Anti-Inflammatory Activity of a New Unusual Fucosylated Chondroitin Sulfate from Cucumaria djakonovi

Fucosylated chondroitin sulfate CD was isolated from the sea cucumber Cucumaria djakonovi collected from the Avachinsky Gulf of the eastern coast of Kamchatka. Structural characterization of CD was performed using a series of non-destructive NMR spectroscopic procedures. The polysaccharide was shown to contain a chondroitin core [→3)-β-d-GalNAc-(1→4)-β-d-GlcA-(1→]n where about 60% of GlcA residues were 3-O-fucosylated, while another part of GlcA units did not contain any substituents. The presence of unsubstituted both at O-2 and O-3 glucuronic acid residues in a structure of holothurian chondroitin sulfate is unusual and has not been reported previously. Three different fucosyl branches Fucp2S4S, Fucp3S4S and Fucp4S were found in the ratio of 2:1:1. The GalNAc units were mono- or disulfated at positions 4 and 6. Anti-inflammatory activity of CD was assessed on a model of acute peritoneal inflammation in rats. About 45% inhibition was found for CD, while a structurally related linear chondroitin sulfate SS from cartilage of the fish Salmo salar demonstrated only 31% inhibition, indicating that the presence of sulfated fucosyl branches is essential for anti-inflammatory effect of chondroitin sulfates of marine origin.

Development and application of a HPLC-MS/MS method for quantitation of fucosylated chondroitin sulfate and fucoidan in sea cucumbers

Fucosylated chondroitin sulfate (FCS) and fucoidan (FUC) are two main bioactive polysaccharides in sea cucumbers. A novel method for quantitation of FCS and FUC was developed by detecting chondroitin disaccharide and fucose produced through acid hydrolysis using HPLC-MS/MS. The present method showed satisfactory performance for both saccharides. It was applied to assay sea cucumbers (Stichopus japonicus) reared in pond grow-out or bottom sowing, and the results were compared with those obtained by traditional HPLC method and 1,9-dimethylmethylene blue test, which could only provide the total sea cucumber polysaccharide (SCP) contents. No difference of total SCP content was observed between sea cucumbers reared through different ways, while a higher ratio of FCS to FUC of sea cucumbers of pond grow-out was revealed by the present method. Thus, this novel method is potential to quantify the two polysaccharides and could be a powerful tool for quality evaluation of sea cucumbers.

Structural elucidation of fucosylated chondroitin sulfates from sea cucumber using FTICR-MS/MS

Fucosylated chondroitin sulfates are complex polysaccharides extracted from sea cucumber. They have been extensively studied for their anticoagulant properties and have been implicated in other biological activities. While nuclear magnetic resonance spectroscopy has been used to extensively characterize fucosylated chondroitin sulfate oligomers, we herein report the first detailed mass characterization of fucosylated chondroitin sulfate using high-resolution Fourier transform ion cyclotron resonance mass spectrometry. The two species of fucosylated chondroitin sulfates considered for this work include Pearsonothuria graeffei (FCS-Pg) and Isostichopus badionotus (FCS-Ib). Fucosylated chondroitin sulfate oligosaccharides were prepared by N-deacetylation-deaminative cleavage of the two fucosylated chondroitin sulfates and purified by repeated gel filtration. Accurate mass measurements obtained from electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry measurements confirmed the oligomeric nature of these two fucosylated chondroitin sulfate oligosaccharides with each trisaccharide repeating unit averaging four sulfates per trisaccharide. Collision-induced dissociation of efficiently deprotonated molecular ions through Na/H+ exchange proved useful in providing structurally relevant glycosidic and cross-ring product ions, capable of assigning the sulfate modifications on the fucosylated chondroitin sulfate oligomers. Careful examination of the tandem mass spectrometry of both species deferring in the positions of sulfate groups on the fucose residue (FCS-Pg-3,4- OS) and (FCS-Ib-2,4- OS) revealed cross-ring products 0,2Aαf and 2,4X2αf which were diagnostic for (FCS-Pg-3,4- OS) and 0,2X2αf diagnostic for (FCS-Ib-2,4- OS). Mass spectrometry and tandem mass spectrometry data acquired for both species varying in oligomer length (dp3-dp15) are presented.

A fucoidan from sea cucumber Pearsonothuria graeffei with well-repeated structure alleviates gut microbiota dysbiosis and metabolic syndromes in HFD-fed mice

A high-fat diet (HFD) has been a major contributor to increasing morbidity caused by metabolic syndromes.

Macromolecular properties and hypolipidemic effects of four sulfated polysaccharides from sea cucumbers

The present study investigates the relationship between the high-order structure and hypolipidemic activity of four well-defined sulfated fucans from sea cucumber. The chain conformation, determined by a combination of AFM and SEC-MALLS-RI, indicate that fucosylated chondroitin sulfate (fCS) from Pearsonothuria graeffei (fCS-Pg) and Isostichopus badionotus (fCS-Ib), and fucoidan from P.graeffei (fuc-Pg) were assigned as a random coil conformation with polysaccharide chain outstretched, while I. badionotus (fuc-Ib) was assigned as a spherical conformation and exhibited high viscosity. Fuc-Pg and fuc-Ib with higher molecular weights had a greater impact in inhibiting pancreatic lipase activity in vitro. However, fCS-Pg, fCS-Ib and fuc-Pg with random linear conformation exhibited excellent hypolipidemic activity in Sprague-Dawley rats (SD rats) fed on high-fat diet (HFD), whereas fuc-Ib showed only a modest effect. Our results indicate that structural characteristics, including side branch and sulfation pattern can affect the chain conformation of polysaccharides, which determine their physicochemical properties and hypolipidemic activity.

A New Route of Fucoidan Immobilization on Low Density Polyethylene and Its Blood Compatibility and Anticoagulation Activity

Beside biomaterials’ bulk properties, their surface properties are equally important to control interfacial biocompatibility. However, due to the inadequate interaction with tissue, they may cause foreign body reaction. Moreover, surface induced thrombosis can occur when biomaterials are used for blood containing applications. Surface modification of the biomaterials can bring enhanced surface properties in biomedical applications. Sulfated polysaccharide coatings can be used to avoid surface induced thrombosis which may cause vascular occlusion (blocking the blood flow by blood clot), which results in serious health problems. Naturally occurring heparin is one of the sulfated polysaccharides most commonly used as an anticoagulant, but its long term usage causes hemorrhage. Marine sourced sulfated polysaccharide fucoidan is an alternative anticoagulant without the hemorrhage drawback. Heparin and fucoidan immobilization onto a low density polyethylene surface after functionalization by plasma has been studied. Surface energy was demonstrated by water contact angle test and chemical characterizations were carried out by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. Surface morphology was monitored by scanning electron microscope and atomic force microscope. Finally, their anticoagulation activity was examined for prothrombin time (PT), activated partial thromboplastin time (aPTT), and thrombin time (TT).