Amylose
542645
218149969
2008-06-09T11:18:42Z
Danielle dk
1427810
painting red link blue
{{expand|date=June 2008}}
{{refimprove|date=June 2008}}
'''Amylose''' ([[CAS registry number|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]].
[[Image:Amylose.svg|thumb|400px|right|Amylose structure]]
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 [[helix|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==
*[http://www.mendosa.com/gilists.htm glycemic load]
{{carbs}}
[[Category:Polysaccharides]]
[[category:carbohydrates]]
{{biochem-stub}}
[[da:Amylose]]
[[de:Amylose]]
[[es:Amilosa]]
[[eo:Amilozo]]
[[fr:Amylose]]
[[hr:Amiloza]]
[[id:Amilosa]]
[[it:Amilosio]]
[[he:עמילוז]]
[[hu:Amilóz]]
[[ms:Amilosa]]
[[nl:Amylose]]
[[ja:アミロース]]
[[no:Amylose]]
[[pl:Amyloza]]
[[ru:Амилоза]]
[[sv:Amylos]]
[[tr:Amiloz]]
[[uk:Амілоза]]
[[zh:直鏈澱粉]]