Starch derivatives reactions

This starch derivative is a water-soluble polymer of D-glucose with a largely helical structure. Therefore, like cyclodextrins, it has the ability to bind alkyl chains and to catalyse reactions through the involvement of ionized hydroxyl groups in basic solution (Hui et al., 1982 Cheng et al., 1985). 

Starch (amylose and amylopectin) hydrolysis along with ester-fication, etherification or oxidation have been previously discussed as available methods for producing starch derivatives with improved water dispersibilities and reduced retrogradation potential (, ). Since oxidative and hydrolytic reactions are simple, easily controlled chemical modifications, starch-derived polymers made by hydrolysis alone or oxidative and hydrolytic processes were developed and tested. 

Hackel and T. Urbanski [18] examined starch derived from different plants (maize, wheat, rice, tapioca and potato) and on reaction with mixtures of nitric and sulphuric acid they obtained nitric esters of practically identical properties (i.e. of the same nitrogen content, solubility, and viscosity) providing the degree of purity of the starch was the same. 

Several reactions can cause color development in starch-derived sweeteners. Because they contain reducing sugars, they will react with proteins and amino acids... 

Figure 2. Metabolic route from MI to starch-derived Glc via the MIOP (reaction sequence underlined).

Starch derivatives are relatively safer in terms of adverse reactions than other colloid plasma substitutes, but there is an incidence of anaphylactic reactions of 4-6 per million. 

The study of reactions between TlOH and TlOEt with starch derived from different sources shows that potato starch binds thallium(I) chemically, whereas corn starch forms simple adducts with TlOH... 

Reactions of Starch Dialdehyde and Other Starch Derivatives. 285... 

Starch derivatives may also undergo hydrolysis and degradation under alkaline conditions. The hydrolysis of the nitriles, amides, and esters resulting from the reaction of starch with corresponding vinyl monomers is obvious. Considerable attention has been paid to the alkaline degradation of starch dialdehyde. It de-polymerized readily supposedly as a result of -elimination at C-5, although such a questionable -elimination should not be facile).70... 

Oxidation products from starch are also available indirectly. For example, Horton and coworkers485-487 prepared 6-aldehydo amylose and starch derivatives by photolysis of 6-azido-6-deoxy derivatives. The oxidation pattern of starches can be determined by hydrolysis of the reaction product and subsequent identification of the components of such hydrolyzates as their trimethylsilyl derivatives 488... 

Halogen molecules can be added to double bonds in starch derivatives, as demonstrated487 by the addition of bromine to the 2,3-double bond of 2,3-dideoxy-2,3-didehydro-6-0-trityl-starch. The reaction proceeded in methanol in the presence of silver acetate 487... 

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