Polysaccharides hydrogen bonding between

Note that there are two forms of starch amylase and amylopectin. In amylase, the glucose residues are joined end to end by 1—>4 glycosidic bonds between a-anomers of glucose. This produces a linear, unbranched polysaccharide. Hydrogen bonds between amylose molecules twist the chains into large hehcal rodhke stractures that stack to form sheets. These sheets impede digestion by amylase. 

A regular fine structure causing maximal hydrogen bonding between the molecules reduces the possibility of reversible processes and therefore reduces the gel-forming properties of the compound. Other polysaccharides with different types of monomers or with branched chain structures can be treated in a similar manner. However, much more study of their fine structure and the accessibility of their functional groups is necessary. 

At the point of contact between the cellulosic fibres a strong bond is formed once the fibres have been dried. These bonds are formed by hydrogen bonds between the polysaccharides at the fibre surface. Mechanical and other properties of paper are not only dependent on the nature of the fibre distribution but also on the bonding between the fibres and the inherent fibre strength itself. Bonding between... 

It has also been reported from circular dichroism (CD) studies [36] that polysaccharide-based CSPs can induce chirality in enantiomeric guests such as (4Z,15Z)-bilirubin-Ixoc (BR) (Fig. 5). Although not optically active, BR has two enantiomeric helical conformations maintained by six intramolecular hydrogen bonds between two carboxylic acid moieties and two pyrromethenone — NH— protons. These (R)- and (5)-helical conformers are in dynamic equilibrium in an achiral solution [37], but some optically active compounds can enantioselectively bind to BR to induce CD spectra in solution [38-40]. A significant induced CD... 

Hydrogen bonds, between carbohydrates and hydrophilic groupings of proteins of enzymes, V, 55 Hydrogen bromide, hydrolysis of polysaccharides with, II, 231 Hydrogen cyanide, reaction with osones, II, 80... 

Traditional methods for dyeing cotton depended on formation of insoluble dye molecules on the fibers, or of hydrogen bonds between the dye molecules and the fibers, or both. However, two classes of dyes that react covalently have now been used extensively in the production of colored polysaccharide derivatives. The diazine and triazine types of... 

Thus, the amount of bound water, Vo/c, can be estimated from at infinite dilution with the following assumptions (1) the solute is incompressible (3,=0), (2) the. compressibility of bound water is the same as that of ice (32=18xl0 cm /dyne) since the hydration of neutral polysaccharide would be mainly due to hydrogen bonds between water and OH groups of the polymer, and (3) v =V2. 

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