A glycoside is a molecule where a sugar group is bonded through its anomeric carbon to a nonsugar group by either an oxygen or a nitrogen atom. This is called a glycosidic bond. The sugar and nonsugar groups of a glycoside can be separated by hydrolysis. A sugar is a carbohydrate which is sweet to taste. ... An anomeric carbon is the new stereocenter created in forming the cyclic structure of a monosaccharide. ... General Name, Symbol, Number oxygen, O, 8 Chemical series nonmetals Group, Period, Block 16, 2, p Appearance colorless Atomic mass 15. ... General Name, Symbol, Number nitrogen, N, 7 Chemical series nonmetals Group, Period, Block 15, 2, p Appearance colorless Atomic mass 14. ... A glycosidic bond is formed between a hemiacetal group of a sugar molecule (such as glucose) and an alcohol functional group to form an acetal. ... Hydrolysis is a chemical process in which a molecule is cleaved into two parts by the addition of a molecule of water. ...

glycosides are made up of a sugar part ( glycone ) and a non-sugar part ( aglycone or genin) . the sugar part may be made of asingle simple sugar or more than one sugar unit.

glycosides are classified according to the type of glycosidic linkage into :

a. alpha-glycosides : these glycosides are hydrolized by specific enzymes affecting the alpha- linkage e.g. alpha-amylase.

b. beta-glycosides: these glycosides are hydrolized by glycosides affecting the beta-linkage such as emulsin.

glycosides are also classified according to the chemical nature of the non sugar part :

a. anthraquinone glycosides : these are present in :

senna. rhubarb. aloes.

they have a laxative effect.

b.simple phenolic glycosides: the glycoside is a simple phenolic structure.

an example is arbutin found in uva ursi. it has a urinary antiseptic effect.

c. alcoholic glycosides : an example is salicin which is found in salix species.

 salicin is converted in the body into salicylic acid , which has analgesic , antipyretic and antiinflammatory effects . 

d. cyanophore glycosides : these glycosides yield hydrocyanic acid (HCN) on hydrolysis. amygdalin from bitter almond is a cyanophore glycoside.

e. thioglycosides: as the name implies , these compounds contain sulfer .

 example include: sinigrin : found in black mustard. sinalbin : found in white mustard. 

f. flavonoid glycosides : this is a large group of glycosides . examples include :

 apiin. hesperidin found in citrus fruits. rutin. quercetin. silymarin. 

among the important effects of falvonoids are their antioxidant effect . they are also known to decrease capillary fragility.

g. steroidal glycosides : the aglycone part is a steroidal nucleus . they are found in digitalis , squill , and strophanthus . they are sometimes referred to as caridac glycosides. they are used in the treatment of heart diseases e.g. congestive heart failure and arrhythmia .

h. saponin glycosides : these compounds give a premanent froth when shaken with water . they also cause haemolysis of rbcs. saponins are found in liquorice . their medicinal value is due to their expectorant effect.

i. coumarin glycosides : e.g. apterin which is reported to have a coronart vasodilator effect as well as a calcium channel blocking effect.

See also

• glucoside