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]]