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Renz Mervin Rivera 2B-MT

Classifications of Carbohydrates

Monosaccharide

Monosaccharides are the simplest carbohydrates in that they cannot be hydrolyzed to

smaller carbohydrates. They are aldehydes or ketones with two or more hydroxyl groups.

The general chemical formula of an unmodified monosaccharide is (C•H2O)n, literally a

"carbon hydrate." Monosaccharides are important fuel molecules as well as building blocks

for nucleic acids. The smallest monosaccharides, for which n = 3, are dihydroxyacetone and

D- and L-glyceraldehyde.

Three common sugars—glucose, galactose, and fructose, share the same molecular

formula: C6H12O6. Because of their six carbon atoms, each is a hexose. Substances such as

these three, which have identical molecular formulas but different structural formulas, areknown as structural isomers.

Glucose

  Glucose, which is also referred to as dextrose, is a moderately sweet sugar found invegetables and fruit.

Galactose

  Galactose is not normally found in nature, but is mostly hydrolyzed from the

disaccharide lactose, which is found in milk, as part of a disaccharide made byglycosidic linkage to a glucose molecule. Galactose is natural and is a basic

component of many things, being found in milk, tomatoes and many fruits andvegetables.

Fructose

  Fructose is also called the fruit sugar. Fructose is found in fruits, honey, and the solesugar in bull and human semen. It is the sweetest of sugars. It is used for

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preventing sandiness in ice cream. The compound's formula is C6H12O6. It is shaped

in orthorhombic, bispherodial prisms.

Disaccharide

Disaccharides are macromolecules consisting of two monosaccharides connected by aglycosidic bond. Some common disaccharides are lactose (milk sugar), maltose and sucrose

(common table sugar)

Sucrose

  Sucrose, ordinary table sugar, is probably the single most abundant pure organic chemical in the

world and the one most widely known to nonchemists.

Maltose   The disaccharide obtained by enzyme-catalyzed hydrolysis of starch, consists of two D-

glucopyranoses joined by a 1,4'-beta-glycoside bond.

Lactose 

 

Lactose is a disaccharide that occurs naturally in both human and cow's milk. Like cellobiose andmaltose, lactose is a reducing sugar. It exhibits muta-rotation and is a 1,4'-beta-linked glycoside.

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Polysaccharides

A complex carbohydrate composed of a chain of monosaccharides joined together byglocosidic bonds.

Starch 

 

Starch is the major carbohydrate reserve in plant tubers and seed endosperm whereit is found as granules, each typically containing several million amylopectin

molecules accompanied by a much larger number of smaller amylose molecules.

Glycogen

  Glycogen is the principal storage form of glucose in animal cells. Glycogen is a highly branched

glucose polymer. It is formed of small chains of 8 to 12 glucose molecules linked together with&alpha (1→4) bonds. These small chains are in turn linked together with &alpha (1→6) bonds.

Cellulose 

 

The chemistry of cellulose is primarily the chemistry of alcohols; and it forms many of thecommon derivatives of alcohols, such as esters, ethers, etc.