Polysaccharides nuclear magnetic resonance

A variety of spectroscopic techniques have been applied to DOC isolated from seawater by cross-flow ultrafiltration or adsorption onto XAD resins. The two techniques isolate very different organic fractions from seawater. Hydrophobic fractions (such as marine humic material) are isolated on XAD resins [48], whereas the organic matter extracted by ultrafiltration is retained primarily on the basis of its molecular size and shape [49], resulting in isolates rich in nitrogen and carbohydrates (polysaccharides). Nuclear magnetic resonance (NMR) spectroscopy has proven successful in distinguishing between the specific structures of XAD-bound humics and the carbohydrates concentrated into colloidal size fractions. 

CARBON-13 NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY OF POLYSACCHARIDES... 

The advent of studies of polysaccharides by carbon-13 nuclear magnetic resonance (13C-n.m.r.) spectroscopy coincided, not surprisingly,... 

Structural investigations into the degree of branching and into the position and nature of glycosidic bonds and of non-carbohydrate residues in polysaccharides may include periodate oxidation and other procedures such as exhaustive methylation. X-ray diffraction and spectroscopic techniques such as nuclear magnetic resonance and optical rotatory dispersion also give valuable information especially relating to the three-dimensional structures of these polymers. 

Bhattacharjee, A.K., Jennings, H.J., Kenny, C.P., Martin, A. and Smith I.C.P. (1975) Structural determination of the sialic polysaccharide antigens of Neisseria meningitidis serogroup B and C with carbon 13 nuclear magnetic resonance. J. Biol. Chem. 250 1926-1932... 

Nuclear magnetic resonance (NMR) spectroscopy is a very powerful tool for analyzing the conformation and molecular architecture of carbohydrate molecules. Both one- and two-dimensional (ID and 2D) methodologies have provided valuable information about small and large molecules, ranging from the anomeric configuration of a monosaccharide to the sequence of monosaccharide residues that constitute an oligo- or polysaccharide. 

P. A. J. Gorin, Carbon-13 nuclear magnetic resonance spectroscopy of polysaccharides, Adv. Carbohydr. Chem. Biochem., 38 (1981) 13-104. 

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