Study Set Content:
Are compounds containing a carbohydrate and a non-
carbohydrate residue in the same molecule.
GLYCOSIDES
Are compounds that yield one or more sugars among the
products of hydrolysis
GLYCOSIDES
Chemically, the glycosides are_____ in which the
hydroxyl of the sugar is condensed with a hydroxyl group
of the non-sugar component and the secondary hydroxyl
is condensed within the sugar molecule itself to form an
_____
acetals, oxide ring.
the central carbon atom has four bonds to
it, and is therefore saturated and has a tetrahedral
geometry. R2C(OR’)2, where both R’ groups are
organic fragments.
Acetals
The residue is attached by an _____ at carbon 1 to a non-
carbohydrate residue or aglycone.
acetal linkage
The non-sugar group is known as the
AGLYCONE
The sugar compound is called the
GLYCONE
All natural glycosides are hydrolyzed into a sugar and another organic compounds by
boiling with mineral acids
Most enzymes hydrolyze only single glycosides except for _____ that hydrolyzes a considerable number of glycosides.
emulsin and myrosin
a mixture of enzymes, extracted from bitter almonds, once used to hydrolyze glucosides
Emulsin
an enzyme found in mustard plants, which hydrolyzes sinigrin, the glycone and the aglycone
Myrosin
are water soluble compounds and insoluble in organic solvents
Glycosides
soluble in water but insoluble in organic solvents
Glycone part
water insoluble but soluble in organic solvents
Aglycone part
GENERAL PROPERTIES
1. Colorless solid, amorphous, non-volatile
2. Gives a positive reaction with _____ solution test (after hydrolysis)
Molisch;s and Fehling;s
They are water soluble compounds, insoluble in
organic solvents.
Most have bitter taste (except
glycyrrhizin, stevioside)
Odorless except for
glycyrrhizin
They are hydrolyzed by using mineral acids and temperature or by
using enzymes
