Structure characterization of a highly branched galactan from the slug Vaginulus alte and its utilization by human gut microbiota.

The slug Vaginulus alte is used as folk medicine in China, but the structure and activities of its galactan components remain to be clarified. Here, the galactan from V. alte (VAG) was purified.

Peroxidative depolymerization of fucosylated glycosaminoglycan: Bond-cleavage pattern and activities of oligosaccharides.

Peroxidative depolymerization is often used to elucidate the structure and structure-activity relationship of fucosylated glycosaminoglycan (FG), while the selectivity of bond cleavage and structural characteristics of the resulting fragments remain to be confirmed. Here, the FG from Stichopus variegatus (SvFG) was depolymerized by HO, and a series of yielded mono- and oligo-saccharides were purified. Almost all the non-reducing ends of oligosaccharides were d-GalNAc, suggesting that GlcA-β1,3-GalNAc linkage was preferentially cleaved.

Mild acid hydrolysis on Fucan sulfate from Stichopus herrmanni: Structures, depolymerization mechanism and anticoagulant activity.

Fucan sulfate (FS) from sea cucumbers possesses linear sequences with repeating units that differ principally in the pattern of sulfation and position of glycosidic linkage. FS from Stichopus herrmanni (ShFS) was preliminarily identified as the relatively simple structure {-3)-L-Fuc-(α1-}n. Herein, mild acid hydrolysis was employed on ShFS to yield 21 oligosaccharides.

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

A fucan sulfate (HfFS) was isolated from the sea cucumber 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.

Structure Elucidation of Fucan Sulfate from Sea Cucumber through a Bottom-Up Strategy and the Antioxidant Activity Analysis.

Fucan sulfate I (FSI) from the sea cucumber was purified and its structure was clarified based on a bottom-up strategy. The unambiguous structures of a series of oligosaccharides including disaccharides, trisaccharides, and tetrasaccharides, which were released from mild acid hydrolysis of FSI, were identified by one-dimensional (1D)/two-dimensional (2D) nuclear magnetic resonance (NMR) and mass spectrometry (MS) analysis. All the glycosidic bonds in these oligosaccharides were presented as α1,3 linkages confirmed by correlated signals from their H-H ROESY and H-C HMBC spectra.

The glycosidic bond cleavage and desulfation investigation of fucosylated glycosaminoglycan during mild acid hydrolysis through structural analysis of the resulting oligosaccharides.

Mild acid hydrolysis is a common method to study the chemical structure of fucosylated glycosaminoglycan (FG). It was generally considered that the fucose branches α-L-FucS-(1, of FG could be hydrolyzed selectively in mild acid. This report focused on the selectivity of glycosidic bond cleavage and extensive desulfation characteristics of the backbone during mild acid hydrolysis.