dextrin

A mixture of oligo(α-1,4-d-glucose) molecules formed during the enzymic or acid hydrolysis of starch, amylopectin, or glycogen; on further hydrolysis they are converted into d-glucose. Dextrins are of much lower molecular weight than dextrans, hence are not suitable as plasma expanders; d. (usually white d.) is used in pharmaceutical preparations. SYN: starch gum.

- acid d. the product of acid and heat treatment of d..

- limit d. the polysaccharide fragments remaining at the end (limit) of exhaustive hydrolysis of amylopectin or glycogen by α-1,4-glucan maltohydrolase or β-amylase, which cannot hydrolyze the α-1,6 bonds at branch points; accumulates in individuals with type III glycogen storage disease. SYN: d. limit.

- Schardinger dextrins cyclic rings of glucose monomer (usually 6 to 8) linked α-1,4; the result of action of Bacillus macerans on starch.

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dex·trin 'dek-strən also dex·trine -.strēn, -strən n any of various soluble gummy polysaccharides (C₆H₁₀O₅)_n obtained from starch by the action of heat, acids, or enzymes and used as adhesives, as sizes for paper and textiles, as thickening agents (as in syrups), and in beer

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n.

a carbohydrate formed as an intermediate product in the digestion of starch by the enzyme amylase. Dextrin is used in the preparation of pharmaceutical products (as an excipient) and surgical dressings.

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dex·trin (dekґstrin) [L. dexter right] 1. any one, or the mixture, of the intermediate polysaccharides formed during the hydrolysis of starch, which are dextrorotatory, soluble in water, and precipitable in alcohol. They may be linear or branched, and include the amylodextrins, erythrodextrins, and achroodextrins. 2. [NF] an official preparation, from starch by heating; used as a suspending and viscosity-increasing agent, tablet binder, and tablet and capsule diluent.