Sucrase

Sucrase is the name given to a number of enzymes that catalyse the hydrolysis of sucrose to fructose and glucose.

Types

 * is sucrase-isomaltase
 * is invertase

Physiology
Sucrose intolerance (also known as Congenital Sucrase-Isomaltase Deficiency (CSID) or Sucrase-isomaltase deficiency) occurs when sucrase is not secreted in the small intestine. With sucrose intolerance, the result of consuming sucrose is excess gas production and often diarrhea and malabsorption.

Sucrase is secreted by the tips of the villi of the epithelium in the small intestine. Its levels are reduced in response to villi-blunting events such as celiac sprue and the inflammation associated with the disorder. The levels increase in Pregnancy/Lactation and Diabetes as the villi hypertrophy.

Use in chemical analysis
Sucrose itself is a non-reducing sugar, having the reducing aldehyde group involved in the glycosidic bond, and therefore will not test positive with Benedict's solution. In order to test for sucrose, the enzyme sucrase is mixed with the sample. The sucrose is hydrolysed into glucose and fructose, with glucose being a reducing sugar, which will test positive with Benedict's solution. Fructose can be isomerized to glucose by the addition of NaOH or other strong base.