Amylose (CAS# 9005-82-7) is a planar polymer of glucose linked mainly by α(1→4) bonds. It can be made of several thousand glucose units. It is one of the two components of starch, the other being amylopectin.

The α(1→4) bonds promote the formation of a helix structure. The structural formula of amylose is pictured at right. The number of repeated glucose subunits (n) can be many thousands (usually in the range of 300 to 3000).

Amylose starch is less readily digested than amylopectin; however, it takes up less space so is preferred for storage in plants: it makes-up about 30% of the stored starch in plants. The digestive enzyme amylase works on the ends of the starch molecule, breaking it down into sugars.

Iodine molecules fit neatly inside the helical structure of amylose, binding with the starch polymer that absorbs certain known wavelengths of light. Hence, a common test for starch is to mix it with a small amount of yellow iodine solution. In the presence of amylose, a blue-black color will be observed. The intensity of the color can be tested with a colorimeter, using a red filter to discern the concentration of starch present in the solution.

High-amylose varieties of rice have a much lower glycemic load, which could be beneficial for diabetics.

External links

* [ glycemic load]

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  • Amylose — Am y*lose , n. (Chem.) One of the starch group {(C6H10O5)n} of the carbohydrates; as, starch, arabin, dextrin, cellulose, etc. [1913 Webster] …   The Collaborative International Dictionary of English

  • Amylose — ⇒ Stärke …   Deutsch wörterbuch der biologie

  • amylose — [am′ə lōs΄] n. 1. the inner, water soluble content of starch 2. any of a group of complex carbohydrates of the general formula (C6H10O5) n, as cellulose or starch, which are converted by hydrolysis into two or more simple sugars …   English World dictionary

  • Amylose — Pour les articles homonymes, voir Amylose (homonymie). Amylose Amylose (glucose α 1,4 glucos …   Wikipédia en Français

  • Amylose — Strukturformel Struktur der Amylose: die Anzahl der Monomereinheiten n liegt je nach Quelle zwischen 100 und 1400 Allgemeines …   Deutsch Wikipedia

  • amylose — A linear polysaccharide formed from a D glucopyranosyl units in a 1,4 linkage. Found both in starch (starch amylose) and glycogen (glycogen amylose) …   Dictionary of molecular biology

  • Amylose AA — Etiologie de l amylose AA De nombreuses maladies chroniques peuvent être à l origine de cette maladie rénale glomérulaire par dépôts de protéines inflammatoires La Polyarthrite rhumatoïde Les Maladies Inflammatoires Chroniques Intestinales La… …   Wikipédia en Français

  • Amylose — Amy|lo|se 〈f. 19; Biol.〉 schraubenförmiges, unverzweigtes Molekül, das zu 30 40 % in Stärke vorkommt u. von Amylopektin umhüllt wird * * * A|my|lo|se [↑ Amyl (2) u. ↑ ose (1)], die; , n: aus helical angeordneten Ketten α(1→4)glykosidisch… …   Universal-Lexikon

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