Carbohydrates poly saccharides

All carbohydrates (mono-, di- and poly saccharides) give the Molisch colour test for details, see Section III,139,(i). ... 

Even if the main focus on the research activities were directed towards structural studies on carbohydrates of natural origin, the synthesis of model substances, deriva-tization of oligo- and poly-saccharides, oxidation, and reduction of carbohydrates, and identification of the products all were performed during this time. 

The periodate oxidation of carbohydrates, an important analytical technique, has been reviewed earlier in this Series.73 The dialdehydes obtained on periodate oxidation of polysaccharides have also been discussed.74 The requisite for the degradations to be discussed here is that part of the sugar residues in a polysaccharide are not oxidized by periodate and can be obtained separated from the oxidized residues as mono-, oligo-, or poly-saccharide derivatives after some chemical treatment. Characterization of these products may then give significant structural information. 

N. K. Kochetkov, O. S. Chizhov, and A. S. Shashkov, Dependence of 13C chemical shifts on the spatial interaction of protons, and its application in structural and conformational studies of oligo- and poly-saccharides, Carbohydr. Res., 133 (1984) 173-185. 

The absorption of simple and complex carbohydrates from the intestine is mediated by a family of enzymes collectively named a-glucosidases which hydrolyze the oligo- or poly-saccharides to monosaccharides for transport into the blood stream. Inhibition of these enzymes is expected to delay the absorption of carbohydrates and reduce the postprandial glucose rise. 

Thyroglobulin. a glycoprotein, is composed of several peptide chains it also contains 0.5 to 1% iodine and 8 (o 10% carbohydrate in (he form of two types of poly.saccharide. The formation of thyroglobulin is regulated by TSH. Thyroglobulin has no hormonal properties. I( must be hydrolyzed to release the hormonal iodothyronines thyroxine and liothy-lonine (see Thyroid Hormones" in Chapter 19). 

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