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A diastase (; from Greek διαστασις, "separation") is any one of a group of enzymes which catalyses the breakdown of starch into maltose. Alpha amylase degrades starch to a mixture of the disaccharide maltose, the trisaccharide maltotriose, which contains three α (1-4)-linked glucose residues, and oligosaccharides known as dextrins that contain the α (1-6)-linked glucose branches. Diastase was the first enzyme discovered.〔See: * * * * 〕 It was extracted from malt solution in 1833 by Anselme Payen and Jean-François Persoz, chemists at a French sugar factory.〔Payen & Persoz (1833), page 77. Payen and Persoz found diastase in the seeds of barley, oats, and wheat, as well as in potatoes (Payen & Persoz (1833), page 76).〕 The name "diastase" comes from the Greek word διάστασις (''diastasis'') (a parting, a separation) because when beer mash is heated, the enzyme causes the starch in the barley seed to transform quickly into soluble sugars and hence the husk to separate from the rest of the seed.〔Payen & Persoz (1833), pages 75-76.〕〔( Etymology of "diastase" )〕 Today, diastase means any α-, β-, or γ-amylase (all of them hydrolases) that can break down carbohydrates. The commonly used -ase suffix for naming enzymes was derived from the name diastase.〔The naming of enzymes using the suffix "-ase" has been traced to French scientist Émile Duclaux (1840-1904), who intended to honor the discoverers of diastase by introducing the practice in his book ( ''Traité de Microbiologie'' ), vol. 2 (Paris, France: Masson and Co., 1899), Chapter 1, especially page 9.〕 When used as a pharmaceutical drug, diastase has the ATC code . Amylases can also be extracted from other sources including plants, saliva and milk. ==See also== * Takadiastase * Whipple disease * amylase 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「diastase」の詳細全文を読む スポンサード リンク
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