Structural Analysis and Anticoagulant Activities of the Novel Sulfated Fucan Possessing a Regular Well-Defined Repeating Unit from Sea Cucumber

Abstract

Sulfated fucans, the complex polysaccharides, exhibit various biological activities. Herein, we purified two fucans from the sea cucumbers Holothuria edulis and Ludwigothurea grisea. Their structures were verified by means of HPGPC, FT-IR, GC–MS and NMR. As a result, a novel structural motif for this type of polymers is reported. The fucans have a unique structure composed of a central core of regular (1→2) and (1→3)-linked tetrasaccharide repeating units. Approximately 50% of the units from L. grisea (100% for H. edulis fucan) contain sides of oligosaccharides formed by nonsulfated fucose units linked to the O-4 position of the central core. Anticoagulant activity assays indicate that the sea cucumber fucans strongly inhibit human blood clotting through the intrinsic pathways of the coagulation cascade. Moreover, the mechanism of anticoagulant action of the fucans is selective inhibition of thrombin activity by heparin cofactor II. The distinctive tetrasaccharide repeating units contribute to the anticoagulant action. Additionally, unlike the fucans from marine alga, although the sea cucumber fucans have great molecular weights and affluent sulfates, they do not induce platelet aggregation. Overall, our results may be helpful in understanding the structure-function relationships of the well-defined polysaccharides from invertebrate as new types of safer anticoagulants.

Pharmacological Potential of Sea Cucumbers

“…Each holothurian species contains polysaccharides with specific sulfation patterns and positioning of the glycosidic linkage. For example, tissues of H. grisea contain sulfated fucan with the following sequences of residues: [3-α-l-Fucp-2,4(OSO3)-1→3-α-l-Fucp-1→3-α-l-Fucp-2(OSO3)-1→3-α-l-Fucp-2(OSO3)-1]n ( Figure 4 ) [ 18 , 19 ].…”

Preliminary Characterization, Antioxidant and Hepatoprotective Activities of Polysaccharides from Taishan Pinus massoniana Pollen

“…As reported, the characteristic absorption peak at 1026 and 1077 cm −1 was ascribed to the bending vibration of C–OH side groups and C–O–C glycosidic bond, indicating that there existed pyranose unit in TPPPS [ 17 , 18 ]. In addition, the stretching absorption peak at 1630 cm −1 along with the peak at 1409 cm −1 indicated the presence of carboxylic group (COO − ), which conforms to the presence of uronic acids detected by the HPLC method [ 19 , 20 ].…”

“…The homogeneity of TPPPS were determined by the HPGPC method described by Yan et al [ 38 ]. The monosaccharide components of the TPPPS were analyzed by reverse-phase HPLC using the PMP derivatization procedure with some modification [ 20 ]. FT-IR spectroscopy was employed to detect the main functional groups in TPPPS.…”

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

“…The body walls of sea cucumbers contain two main types of sulfated polysaccharides, sulfated fucans (SF) often named “fucoidans” [ 1 , 2 , 3 , 4 , 5 , 6 ], and fucosylated chondroitin sulfates (FucCS). The latter polysaccharides isolated from different species of sea cucumbers are known to be composed of d -glucuronic acid, N -acetyl- d -galactosamine, l -fucose and sulfate residues [ 7 ].…”