Sucrase
Sucrase is the name given to a number of enzymes located in on the brush border of the small intestine that catalyze the hydrolysis of sucrose to fructose and glucose. The enzyme invertase, which occurs more commonly in plants, also hydrolyzes sucrose but by a different mechanism.[1]
Types
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. Lactose intolerance is a related disorder that reflects an individual's inability to hydrolyze the disaccharide lactose.
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 is a nonreducing sugar, so will not test positive with Benedict's solution. To test for sucrose, the sample is treated with sucrase. The sucrose is hydrolysed into glucose and fructose, with glucose being a reducing sugar, which in turn tests positive with Benedict's solution..
References
- ↑ Hubert Schiweck, Margaret Clarke, Günter Pollach "Sugar” in Ullmann’s Encyclopedia of Industrial Chemistry 2007, Wiley-VCH, Weinheim. doi:10.1002/14356007.a25_345.pub2
External links
- Sucrase at the US National Library of Medicine Medical Subject Headings (MeSH)
- Diagnosis of sucrase deficiency
| ||||||||||||||||||||
| ||||||||||||||||||