Hydrolysis of disaccharides

Sections Disaccharides are carbohydrates in which two monosaccharides are 25.14-25.15 joined by a glycoside bond. Polysaccharides have many monosaccharide units connected through glycosidic linkages. Complete hydrolysis of disaccharides and polysaccharides cleaves the glycoside bonds, yielding the free monosaccharide components. 

One is to prepare the disaccharide first, and then to introduce the substituents, the other is to synthesize monosaccharides carrying the required substituents and then join them. The disaccharide 2, isolated by Rosner et al. (j>) following mild acid hydrolysis of disaccharide has been synthesized by both methods. 

As for hydrolysis of disaccharides maltose and cellobiose, the (Ha anomeric ratios are in agreement in terms of stereoelectronic effects which are, according to the... 

The hydrolysis of disaccharides may be likened to the hydrolysis of an aliphatic glycoside the aglycon is, however, another sugar residue. It might, therefore, be expected that the nonreducing portion should have... 

Rate Constants and Kinetic Parameters for the Hydrolysis of Disaccharides°... 

Hydrolysis of disaccharides (Section 7.7) H+ disaccharide -1- HjO two monosaccharides or enzymes ... 

The formula for these disaccharides (GJ2H22OJJ) is not simply the sum of two monosaccharides, GgH gOg + GeHi Og. A water molecule is eliminated as two monosaccharides are united to form the disaccharide. In the body, enzymes catalyze the breakdown (hydrolysis) of disaccharides to their monosaccharides. 

Hydrolysis of disaccharides A and B gives the same products D-glucose and D-galactose. Describe a reaction sequence that would clearly distinguish between these isomers. Use Problem 16.49 for one idea about how to proceed. 

The enzymes that catalyse the hydrolysis of disaccharides (the disaccharidases) are located on the brush border of the intestinal mucosal cells the resultant monosaccharides return to the lumen of the small intestine, and are absorbed together with dietary monosaccharides and glucose arising from the digestion of starch (section... 

Hydrolysis of disaccharides — cellobiose, maltose and lactose — was investigated over A, X, and Y type zeolites. The conversion profiles of the hydrolysis of cellobiose over NaX are shown in Fig. 4.19. The reaction was carried out at 373 K and initial reactant concentration of 1.0 wt%, and a catalyst loading of 0.1 gcm . Total conversion is based on the amount of cellobiose consumed by the reaction. A very large fraction of the reaction occurs within the first 0.5 h and the entire reaction terminates after 1 h. The pH profile of the reaction broth is also shown in Fig. 4.19. Upon addition... 

H-ions.—Catalyse the hydrolysis of disaccharides and esters, and many other organic reactions. 

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