The Galactose reference article from the English Wikipedia on 24-Apr-2004
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Galactose

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image:Galactose.png
Haworth projection of D-galactose

Image:D-galactose_Fischer.png

Fischer projection of D-galactose

Galactose is a type of sugar found in milk products and sugar beets. It is also made by the body. It is considered a nutritive sweetener because it has calories.

Galactose is a monosaccharide constituent, together with glucose, of the disaccharide lactose. The hydrolysis of lactose to glucose and galactose is catalyzed by the enzyme beta-galactosidase, a lactase.

Individuals who lack this enzyme are 'lactose intolerant' and unable to realize the nutritive potential of milk sugars. The lactose then passes to the large intestine where it is digested by bacteria, producing gas and flatulence.

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Table of contents
1 Structure
2 Reactions

Structure

The first and last -OH groups point the same way and the second and third -OH groups point the other way.

Isomerism

D-Galactose has the same configuration at its penultimate carbon as D-glyceraldehyde.

Reactions

Hydrolysis

Galactose is hydrolysed by lactase.