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.
Galactose is a monosaccharide. It contains six carbons and an aldehyde group and is classified as an aldose and a hexose. Both the D and L forms are found in nature. The structure depicted at the right is the D isomer. D-Galactose is commonly found in milk as part of the disaccharide lactose. L-Galactose is present in polysaccharides, such as agar.
Galactose is a sugar formed from dietary lactose. It is converted to galactose-1-phosphate and other metabolites by several enzymes, especially phosphogalactose uridyl transferase. A decrease or lack of the enzyme will cause elevated galactose and galactose-1-phosphate levels in the bloodstream.
D-Galactose is an aldohexose that occurs naturally in the D-form in lactose, cerebrosides, gangliosides, and mucoproteins. Deficiency of galactosyl-1-phosphate uridyltransferase (GALACTOSE-1-PHOSPHATE URIDYL-TRANSFERASE DEFICIENCY DISEASE) causes an error in galactose metabolism called GALACTOSEMIA, resulting in elevations of galactose in the blood.
Synonyms: Galactose; brain sugar; d-galactose; D-Galactopyranose
CAS No.: 59-23-4
Molecular weight: 180.16
Chemical formula: C6H12O6