Introduction Definition Classification of carbohydrates Introduction to polysaccharide Classes of polysaccharide 1. Homopolysaccharide 2. Heteropolusaccharide Compositional analysis 1.Qualitative 2.Quantitative References

1. Compositional analysis of Polysaccharide
By
KAUSHAL KUMAR SAHU
Assistant Professor (Ad Hoc)
Department of Biotechnology
Govt. Digvijay Autonomous P. G. College
Raj-Nandgaon ( C. G. )

2. Synopsis:-
Introduction
Definition
Classification of carbohydrates
Introduction to polysaccharide
Classes of polysaccharide
1. Homopolysaccharide
2. Heteropolusaccharide
Compositional analysis
1.Qualitative
2.Quantitative
References

3. INTRODUCTION
•Carbohydrates are the most abundant organic molecules in
nature . they are primarily composed of C, H & O .
•The name carbohydrate literally means ‘ HYDRATES OF
CARBON’
•Carbohydrates are also called as saccharides (Greek
;sakchron = sugar)
Definition
carbohydrate may be defined as polyhydrosxy aldehyde or
ketone or compounds which produce them on hydrolysis.

4. Classification of polysaccharide
• Monosaccharides are the simple sugars which can not
be further hydrolyzed into simpler compound.
Empirical formula – (CnH2nOn) ,

5. Oligosaccharides
Oligosaccharides (greek; oligo = few ) (saccharide = sugar unit )
means few sugar units joined by the GLYCOSIDIC BOND .
•Oligosaccharides are compound sugars that yield 2-10 molecules
of the same or different monosaccharide units on hydrolysis .
Glucose Glucose
+
======
Glycosidic
bond
Maltose a 1-4
bond

6. Polysaccharides
•The term polysaccharide is usually employed for polymers
containing atleast 10 monosaccharide units .
•Polysaccharides or simply glycans consists of repeat units of
monosaccharides or their derivatives , held together by
glycosidic bond .
•They have a general formula (C6H10O5)n.
•Polysaccharides differ from each other in the identity of their
reoccuring monosaccharides units , in the length of their chains
, in the types of bonds linking the units , and the degree of
bonding .

7. Classification
Homopolysaccharides: contain only one type of monomeric units
Heteropolysaccharides: contain two or more different monomeric
units .
Homopolysaccharides-on hydrolysis it yields only one type of
monosaccharide .
They are named based on the nature of monosaccharide unites
as:- glucans (glucose monomer):- starch , glycogen, cellulose
,chitin.
Glactan (glactose monomer):-Agar , Pectin.
Mannans (mannanose monomer):- Yeast, Mannans.
Fructans ( fructose monomer):- ilunin.

8. HOMOPOLYSACCHARIDE
1.Starch:-
•Starch is the carbohydrate reserve
of plants which is the most important
dietary source for higher animals ,
including man .
•High content of starch is found in
cereals , roots , tubers , vegetables
etc .
•Starch is a homopolymer composed
of D-glucose units held by α-
glycosidic bonds.
• Starch occurs in two forms
i.e.amylose and amylopectin

9. Amylose
 It contains 15-20% of starch .
 It consists of long unbranched
chains in which all the D-
glucose units are joined by
α(14) linkages .
 Amylose contains about 200-
500 glucose units .
 Its molecular weight varies
from a few thousand to about
1,50,000 .
 Amylose is water soluble and
give blue colour with iodine .

10. Amylopectin
 It contains 80-85% of starch .
 It is highly branched and the
average length of branches is from
24-30 glucose residues ,
depending upon the species .
 The backbone glycosidic linkage is
α(14) , but the branch points are
α(16) linkages .
 Amylopectin has over 1000
glucose residues and its molecular
weight is about 200,000 –
1,000,000 .
 Amylopectin is water insoluble and
give red – violet colour with iodine
.

11. 2.Cellulose:-
 Cellulose is the most important
structural component of the
cell wall of plants .
 It is also found in a few micro-
organisms and lower organisms
.
 The minimum molecular weight
of cellulose from different
sources vary from about
50,000-2,500,000 in different
sps .
 It contains about 300 – 15,000
glucose residues .

12. Heteropolysaccharides
•It contains two same or different type of monosaccharide units.
•On hydrolysis yields a mixture of a few monosaccharide or their
derivatives .
•They are classified as:-
Netural sugars:- Hemicelluloses , some gums
Mucopolysaccharides-Hyaluroni acid,Chondroitin
Sulphates , HeparinOther.

13.  Hyaluronic acid is found in the skin ,
vitreous humour of the eye , the
umbilical cord , as a coating around
the ovum and in certain bacteria .
 It is also present in the synovial fluid
of joints , where its viscosity makes it
agood lubricant .
 It consists of two monosaccharides ,
D-glucuronic acid and N-acetyl-D-
glucosamine linked by β(13)
linkage .
 It is a linear polymer of disaccharides
which form the repeating unit .
 Each disaccharide is linked to the
next by β(14 ) glycosidic bonds .
1.Hyaluronic acid:-
Heteropolysaccharides

14. 2.Heparin:-
 Heparin is an anticoagulant
secreted by mast cells in the
intestinal mucosa , liver , lung ,
spleen and kidney .
 It consists of an unbranched
chain of ulternate units of
glucosamine and glucuronic
acid joined by α(14) linkage
 Sulfate groups are linked to
the hydroxyl group of carbon
atom 6 and the amino group
of the glucosamine and to
some of the glucuronic acid
units.

15. Molisch test-
2 drop of molisch reagent
to 2 ml of sugar solution+
con. H2SO4
Violet ring at the junction
of two liquid
Carbohydrate present
Iodine test-
1-2 drop of iodine
solution+ 2-3 ml of
sugar solution
Blue colour
colutionheat
colourless
solutioncoolblue
colour disappear.
Starch present
Polysaccharide conform
Blue colour
solutionheat
colourlesscool
blue colour not
reappear.
Glycogen present
Polysaccharide conform
Qualitative analysis

16. Benedict’s test –
 3 ml of sugar solution +0.5 ml of benedict solution blue colour solution
heat red colour.
dextrose present
3 ml of sugar solution + 0.5ml of benedict solutionblue
colourheat>colour not change 
colour not change starch present
Benedict’s
test Benedict test
Molisch test

17. Quantitative test of polysaccharidesQ Quantitative analysis
HPLC– High perfomance liquid chromatography

19. Ion exchange chromatography

20. sample
sample
sample

21. BOOKS AUTHOR
BIOCHEMISTRY Lubert stryer
Textbook of
BIOCHEMISTRY
Thomas M Devlin
Principle of
BIOCHEMISTRY
Lehninger(Nelson &
cox)
INTERNET www.wikipedia.com
REFERENCES:-