Oligo- and Polysaccharides

More than 500 ol igosaccharides are known today, most of them occurring as free natural substances. Oligosaccharides are also obtained by partial 

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Hydrogenated starch hydrolysates (HSH) is a term used to describe a range of products which do not contain sorbitol or maltitol as a primary component, ie, at least 50%. HSH symps contain a distribution of sorbitol, maltitol, and other hydrogenated oligo and polysaccharides. Symps containing maltitol at a level of at least 50% are referred to as Maltitol symps or Maltitol solutions. 

Many proteins found in nature are glycoproteins because they contain covalently linked oligo- and polysaccharide groups. The list of known glycoproteins includes structural proteins, enzymes, membrane receptors, transport proteins, and immunoglobulins, among others. In most cases, the precise function of the bound carbohydrate moiety is not understood. 

During the past decade, MALDI-TOF MS has proven to be an effective tool for the analysis of oligo- and polymeric mannoglucans (for extensive reviews see [222,223]). SEC/MALDI mass spectrometry was employed in the analysis of hemicelluloses isolated by microwave heat-fractionation from spruce and aspen wood [94]. These methods allowed the separation and characterization of the oligo- and polysaccharide fractions derived from the xylan and mannan components of both woods [224]. 

The availability of these novel enzymes, next to the known pectic enzymes, offer new opportunities to use them as analytical tools in revealing the structure of oligo- and polysaccharides [31,32]. In contrast with frequently used chemical degradation methods, which usually have a poor selectivity, these enzymes act in a deflned way. To be able to recognize different structural units within the polymer, endo-acting types of enzyme are preferred, although accessory enzymes might be essential as well [30]. 

From the biological viewpoint, glycosaminoglycans (GAGS) are one of the most relevant oligo- and polysaccharides. The access to new NMR hardware and software, as well as the employment of new synthetic and molecular biology protocols have permitted important advances in the comprehension of their structural and conformational properties, as well as deeply study different examples of their interaction with receptors. 

Based on the theory, the separation of enantiomers requires a chiral additive to the CE separation buffer, while diastereomers can also be separated without the chiral selector. The majority of chiral CE separations are based on simple or chemically modified cyclodextrins. However, also other additives such as chiral crown ethers, linear oligo- and polysaccharides, macrocyclic antibiotics, chiral calixarenes, chiral ion-pairing agents, and chiral surfactants can be used. Eew non-chiral separation examples for the separation of diastereomers can be found. 

IWo chapters treat widely divergent aspects of the aqueous degradation of carbohydrates. Christopher J. Biermann (Corvallis) discusses aqueous acidic hydrolysis and other cleavages of glycosidic linkages in oligo- and polysaccharides, with specific emphasis on their relation to procedures for determination of chemical structure. In the final chapter, Olof Theander (Uppsala) and David A. Nelson (Richland) provide an informative treatment of the... 

A Amino acids and peptides B Nucleic acids and polynucleotides C Oligo- and polysaccharides... 

RMC Sutton, KL Sutton, AM Stalcup. Chiral capillary electrophoresis with noncyclic oligo- and polysaccharide chiral selectors. Electrophoresis 18 2297-2304, 1997. 

Concatenation of Polarization Transfer Steps into Homonuclear Chemical Shift Correlated Experiments. Application to Oligo- and Polysaccharides... 

Specific determination of D-glucose (65) in plant exfi acts requires high purity GOX, devoid of /6-glucosidase, to avoid interference by hydrolysis of oligo- and polysaccharides that may lead to glucose formation and produce H2O2 on autoxidation ". ... 

By competitively inhibiting the alpha-glucosidase enzymes in the mucosa cells of the small intestine these agents suppress the breakdown of di-, oligo-and polysaccharides into monosaccharides and thus decrease carbohydrate absorption. In this way postprandial elevations of blood glucose levels can be prevented or diminished. 

For the synthesis of highly defined polysaccharides, glucosylsaccharides are the only option available. Specialized oligo- and polysaccharides for food and medical applications can be synthesized, and also hybrid structures with non-natural macromolecules or surfaces. 

Carbohydrates such as trioses, tetroses, pentoses, hexoses and polysaccharides are extremely important molecules in nature. The biological significance of oligosaccharides for cell-cell interaction is increasingly understood (Fukuda and Hindsgaul, 1994). The simple carbohydrates are the building blocks of oligo- and polysaccharides. Biocatalysis... 

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