Definition
noun
A stereoisomer of glucose molecule characterized by its ability to rotate the plane polarized light in the clockwise direction, and one that which is biologically active, naturally occurring, and more abundant than L-Glucose
Supplement
Glucose is a hexose monosaccharide since it is comprised of six carbon atoms. One of the carbon atoms is part of an aldehyde functional group. Hence, it is member of the aldohexose group. Depending on the position of the hydroxyl (-OH) groups, it may either be dextro- (as in D-glucose) or laevo- (as in L-glucose). This nomenclature based on Fischer projection designates D– when it rotates the plane polarized light in the clockwise direction. L– is when it rotates the plane polarized light in a counterclockwise direction.
D-glucose occurs more abundantly in nature than L-glucose. D-glucose is a short form of dextrorotatory glucose. It is one of the two stereoisomers of glucose, and is the one that is biologically active. It occurs in plants as a product of photosynthesis. In animals and fungi, it is the result of the breakdown of glycogen. In humans, it is present in blood and urine in which the normal clinical values are 75-115 mg/dl for blood, and 50-300 mg/24 hr for urine.
IUPAC name:
- (2R,3S,4R,5R)-2,3,4,5,6-Pentahydroxyhexanal
Chemical formula:
Also called:
- D-glucopyranose
- grape sugar
- corn sugar
- dextrose
- dextrose monohydrate
- cerelose
Compare:
See also:
- glucose
- stereoisomerism
- monosaccharide
