1. Polysaccharides
• Are polymers of monosaccharides.
• Hydrolysis produces many molecules of
monosaccharide.
• Can be formed from pentoses or the 5 carbon
sugars or the hexoses or six carbon sugars.
• Those from pentoses are called pentosans
• Those from hexoses are hexosans or
sometimes called the glucosans.
• The hexosans are most common in terms of
physiology.
• The hexosans have the general formula ( )x

2. Polysaccharides
 The hexosans have the general
formula ( )x.
 Where x is a large number.
 Some of the common hexosans
are starch, cellulose and dextrin.

3. Starch
 Insoluble in water
 Gives a characteristic blue color with
iodine.
 Test is used to determine the presence
of starch in any solution or even to test
for iodine.
Amylose
 Nonbranched polysaccharide present in
starch to an extent of 15 to 20%

4. When starch is hydrolyzed, it form
dextrin
(amylodextrin, erythrodextrin, achroodextr
in) than maltose and finally glucose.
Erythrodextrins turns red in the
presence of iodine.
Both maltose and glucose produce no
color.
Starch erythrodextrin maltose
glucose
blue red colorless
colorless

5. Cellulose
The supporting and structural substance
of plants.
It gives bulk to the feces and prevents
constipation.
Does not dissolve in water.
Gives no color test with iodine.
gives a negaive test with Cu2+ complex
ion.
used to make rayon.
Wood, cotton and paper are composed
primarily of cellulose.

6. Glycogen
 Is present in the body and stored in the liver
and muscles.
 Where it supplies glucose.
 Forms a colloidal solution in water and gives a
red color with iodine.
 Glycogen is formed in the body cells from
molecules of glucose. In a process called
glycogenesis.
 When glycogen is hydrolyzed to glucose, the
process is called glycogenolysis.

7. Dextrin
Produced during the hydrolysis
of starch.
An intermediate between starch
and maltose.
Used in the preparation of
adhesives.
Forms sticky colloidal
suspensions with water.

8. Heparin
Is a polysaccharide used as
blood anticoagulant.
It accelerates the inactivation of
thrombin and other blood-clotting
agents
It’s the strongest organic acid
found in the body

9. Dextran
Produced by certain bacteria when
they are grown on sucrose.
Used as blood extenders to hold
water in the bloodstream and help
prevent drops in the blood volume
and blood pressure.
Dextrans growing on the surfaces
of teeth are an important component
of dental plaque.