Information AboutDextrose |
| CATEGORIES ABOUT GLUCOSE | |
| chemical pathology | |
| monosaccharides | |
| aldohexoses | |
| nutrition | |
| sweeteners | |
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Glucose (Glc), a Monosaccharide (or simple Sugar ), is an important Carbohydrate in Biology . The cell uses it as a source of energy and metabolic intermediate. Glucose is one of the main products of Photosynthesis and starts Cellular Respiration in both Prokaryotes and Eukaryotes . The name comes from the Greek word ''glykys'' (γλυκύς), which means "sweet", plus the suffix "-ose" which denotes a Carbohydrate . Two Stereoisomer s of the Aldohexose sugars are known as glucose, only one of which (D-glucose) is biologically active. This form (D-glucose) is often referred to as dextrose (''dextrose monohydrate''), especially in the food industry. This article deals with the D-form of glucose. The mirror-image of the molecule, L-glucose, cannot be used by cells. Glucose is commonly available in the form of a white substance or as a solid crystal. It can also be commonly found as an Aqueous Solution . STRUCTURE Glucose (C6H12O6) contains six Carbon Atom s one of which is part of an Aldehyde group and is therefore referred to as an Aldohexose . The glucose molecule can exist in an open-chain (acyclic) and ring (cyclic) form (in equilibrium), the latter being the result of an intramolecular reaction between the aldehyde C atom and the C-5 Hydroxyl group to form an six-membered cyclic Hemiacetal . In water solution both forms are in equilibrium, and at PH 7 the cyclic form is predominant. As the ring contains five carbon atoms and one oxygen atom, which resembles the structure of Pyran , the cyclic form of glucose is also referred to as glucopyranose. In this ring, each carbon is linked to a hydroxyl side group with the exception of the fifth atom, which links to a sixth carbon atom outside the ring, forming a CH2OH group. Isomers Aldohexose sugars have 4 Chiral Centers giving 24 = 16 Stereoisomers . These are split into two groups, L and D, with 8 sugars in each. Glucose is one of these sugars, and L and D-glucose are two of the stereoisomers. Only 7 of these are found in living organisms, of which D-glucose (Glu), D- Galactose (Gal) and D- Mannose (Man) are the most important. These eight isomers (including glucose itself) are all Diastereoisomer s in relation to each other and all belong to the D-series . An additional asymmetric center at C-1 (called ''the anomeric carbon atom'') is created when glucose cyclizes and two ring structures, called ''.
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