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Fucosylated chondroitin sulfate FCS-Hf and preparations of fucan sulfates Hf-Fuc1 and Hf-Fuc2 were isolated from the Vietnamese sea cucumber Holothuria (Stauropora) fuscocinerea. Separation of the polysaccharides was carried out using anion-exchange chromatography on DEAE-Sephacel. The structure of polysaccharides was established by determinations of the content of monosaccharides and sulfate, as well as by NMR spectra. It was shown that FCS-Hf was built of the repeating trisaccharide fragments, with alternating 3-linked N-acetyl-β-D-galactosamine and 4-linked β-D-glucuronic acid residues forming the main polymer chain, which carries α-L-fucose residues as side branches attached to O3 of glucuronic acid. The regular structure of the polymer is masked by an uneven distribution of sulfate groups attached to fucose residues (2,4-disulfate, 3,4-disulfate and 4-monosulfate in a ratio of 2 : 2 : 1) and galactosamine residues (4,6-disulfate and 4-monosulfate in a ratio of 3 : 1). It was also shown that fucan sulfate Hf-Fuc1 contained predominantly linear molecules built of 4-linked α-L-fucose 3-sulfate residues, while Hf-Fuc2 appeared to be a mixture of several related linear and branched fucan sulfates containing 3-linked and 4-linked α-L-Fuc residues sulfated at different positions. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

In the present study, three sulfated polysaccharides, two fractions of fucosylated chondroitin sulfates, and one sulfated fucan were isolated from the body wall of the Vietnamese sea cucumber Stichopus variegatus . The structure of the sulfated fucan fraction SvF3 from S. variegatus was investigated for the first time. According to NMR spectroscopy data, the sulfated fucan SvF3 contained 1,2- and 1,3-linked α- l -fucopyranose residues. Sulfate groups were found at the 2 and/or 4 positions. The structural analysis of fucoidan was assisted by tandem mass spectrometry; the recently-developed technique of autohydrolysis in heavy‑oxygen water for the obtaining of selectively labeled fucoidan fragments was applied. The labeling (+2 Da mass shift at the reducing end) allowed us to assign MS/MS data unambiguously, and thus to confirm the NMR data and revealed minor sulfation at position 3. It was shown that the sulfated fucan SvF3 was not cytotoxic to human breast cancer T-47D and MDA-MB-231 cell lines, and it inhibited colony formation of those cells in vitro . SvF3 also possessed slight activity against migration of MDA-MB-231 cells in vitro . [ABSTRACT FROM AUTHOR]

Extraction process of Cucumaria frondosa japonica Semper, 1868, which are subspecies of Cucumaria frondosa (Gunnerus, 1767), were studied. It was shown that supercritical carbon dioxide extraction of holothuria was more effective than conventional solvent extraction. Step-by-step extraction with carbon dioxide followed by supercritical extraction with the addition of a co-solvent of ethanol can almost double the yields of extracts of triterpene glycosides, styrenes and carotenoids. Moreover, the fraction of triterpene glycosides practically does not contain colored impurities, in contrast to traditional ethanol extraction. The obtained extracts by HPLC in combination with tandem mass spectrometry (HPLC-MS/MS) identified 15 triterpene glycosides, 18 styrene compounds and 14 carotenoids. Supercritical extraction made it possible to obtain extracts with yields superior to conventional hexane and alcohol extracts. Moreover, such an approach with the use of supercritical fluid extraction (SFE) and subsequent profiling of metabolites can help with the study of holothuria species that are not as well studied. [ABSTRACT FROM AUTHOR]