GLUTELINS

From Big Medical Encyclopedia

GLUTELINS (synonym glutenina) — simple proteins, are proteins of cereals, play an important role in food of the person since have considerable nutritional value. Contain only in plants, generally in an endosperm of seeds of cereals. A characteristic sign of G. is their ability to be dissolved in weak (0,2%) solutions of alkalis and diluted to-takh; on other properties are close to to globulins (see).

, are insoluble in alcohol, neutral water solutions of salts and water. Receive G. from the crushed seeds after removal from them of albumine and globulins. Are present at seeds of cereals together with prolamines (see) — proteins, soluble in 70% alcohol. On amino-acid structure of G. differ from prolamines in existence of a lysine and glycine, smaller content of proline, glutaminic to - you and amides and high content of alanine, tyrosine and arginine. Are heterogeneous; they are mix of various proteins close each other on structure and properties. Isoelectric points of G. from different cereals are between pH values from 6,0 to 8,0.

Contains in the whole grain of wheat in number of 4,2 — 4,7% of dry weight. Together with gliadine (see)., forms a gluten of wheat flour, contents it in a gluten makes 39,1% (in terms of dry weight). The ratio of gliadine and G. is equal in a gluten to about 1:1. Grain of rye contains G. much less (apprx. 2,5%); ratio of gliadine and, in it about 2:1. These proteins in rye flour do not form a gluten that * apparently, is caused qualities by wine distinction of proteins of rye and wheat. Orizenin belonging to G. — the main protein of grain of rice; the amount of nitrogen in it makes apprx. 71% of the general nitrogen of grain. Apprx. 40% of all proteins of a corn falls to G.'s share; in corn it consists of two proteins — alpha glutelin and beta glutelin. Grain of barley contains 4,48% of G. (in terms of dry weight).

Nutritional value of G. is high. In experiments it was established that young rats grow normally if the only protein in their food is G. of wheat. The rats receiving in a diet only prolamines do not grow, but begin to develop normally at addition of glutelin.

See also Proteins .


Bibliography Kozmina N. P. and Kretovich V. L. Biokhimiya of grain and products of its processing, page 65, etc., M., 1951.

A. A. Bundel.

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