A diastase (/ˈdaɪəsteɪz/; from Greek διάστασις, "separation") is any one of a group of enzymes that catalyses the breakdown of starch into maltose.
[2] It was extracted from malt solution in 1833 by Anselme Payen and Jean-François Persoz, chemists at a French sugar factory.
[3] 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.
[4][5] Today, "diastase" refers to any α-, β-, or γ-amylase (all of which are hydrolases) that can break down carbohydrates.
Urine diastase is useful in diagnosing uncertain abdominal cases (especially when pancreatitis is suspected), stones in the common bile duct (choledocholithiasis), jaundice and in ruling out post-operative injury to the pancreas; provided that the diastase level is correlated with clinical features of the patient.