Polysaccharide Homo-Polysaccharide Hetero-Polysaccharide Glycogen, starch, inulin, cellulose,dextrins, dextrans, agar, Hyaluronic acid, keratan sulphate, chondrotin, heparin, heparitin sulphate, neutral

1. 1

2. POLYSACCHARIDES
• Condensation products of more than 10 molecules of
monosaccharide units
• Homo-polysaccharides: contain same kind of monosaccharide
• Hetero-polysaccharides : contain two or more different
monosaccharide.
2

3. Starch
Glycogen
Inulin
Cellulose
Dextrins
Dextran
Agar
Hyaluronic Acid
Keratan Sulphate
Chondroitin
Heparin
Heparitin sulphate
Blood group
Homopolysaccharides Heteropolysaccharides
Glycosamino glycans
Mucopolysaccharide (MPS)
POLYSACCHARIDES
3

4. Starch
• 80% of dietary calories in humans
• Storage carbohydrate in plants
• Wheat, Rice, Corn, Potatoes
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5. Starch
5

6. Starch
• Starch has two components
• Amylose: long straight glucose chains (α1-4)
• Amylopectin: branched every 24-30 glc residues (α1-6)
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7. Starch
Amylose
Amylopectin
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8. Starch
8

9. Glycogen
 More branched than starch
 Major storage carbohydrate in animals
 Long straight glucose chains (α1-4)
 Branched every 4-8 glc residues (α 1-6)
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10. Structure of Glycogen
10

11. 3. Inulin:
• Polymer of D-fructose
• Low molecular weight (MW = 5000)
• β(2,1) linkages
• Inulinase is absent in human
• Contributing to
• Reduced Calorie value,
• Dietary fiber,
• Prebiotic effects
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12. 4. Cellulose
12

13. 4. Cellulose
• Polymer of glucose
• human beings as no cellulose splitting enzyme
• Considerable human dietetic value
• Roughage
• Stimulating peristalsis and
• Elimination of indigestible food
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14. 5. Dextrins
When starch is partially hydrolyzed by the action of acids or
enzymes, it is broken down into a number of products of
lower molecular weight known as dextrins
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15. 5. Dextrins
• Dextrins and Maltose are widely used in infant feeding.
• Mucilages (mucilages on the back of the postage stamp)
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16. 6. Dextrans
• Polymer of D-Glucose
• Complex branched of glucose composed of chains of varying lengths
• α1 → 6, α1 → 4 or α1 → 3 glycosidic linkages
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17. Dextrans
• Used as Plasma Expander
• Antithrombotic (antiplatelet), to reduce blood viscosity
• Haemorrhage (blood loss), it increases the blood volume.
Disadvantage:
• Interferes with grouping and cross-matching, as it forms false
Agglutination
Cautious: Blood sample for grouping and cross-matching should
be collected before administration of dextran in a case of
haemorrhage and blood loss, where blood transfusion may be
required.

18. 7. Agar
• Homo-polysaccharide
• Agar or agar-agar is a jelly-like substance, obtained from
Algae.
• Made up of repeated units of linear polysaccharide
galactose which is sulphated.
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19. 7. Agar
• In human: Used as laxative in constipation.
Like cellulose, it is not digested, helps in its propulsion.
• In microbiology: Agar is available in purified form.
• It dissolves in hot water and on cooling it sets like gel.
• used in agar plate for culture of bacteria.
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20. Starch
Glycogen
Inulin
Cellulose
Dextrins
Dextran
Agar
Hyaluronic Acid
Keratan Sulphate
Chondroitin
Heparin
Heparitin sulphate
Blood group
Homopolysaccharides Heteropolysaccharides
Glycosamino glycans
Mucopolysaccharide (MPS)
POLYSACCHARIDES
20

21. Hetero-polysaccharides (Heteroglycans)—
Mucopolysaccharide (MPS)

22. Hetero-polysaccharides (Heteroglycans)—
Mucopolysaccharides (MPS)
• Carbohydrates contain different kinds (two or more)
monosaccharides
• Principal Components:
(a) Amino Sugar (N-acetylglucosamine/N-acetylgalactosamine)
(b) Uronic Acid (Glucuronic acid)
(c) Galactose
• Some are chiefly made up of amino sugar and
monosaccharide units without the presence of uronic acid

23. HETEROPOLYSACCHARIDES (HETEROGLYCANS)—
MUCOPOLYSACCHARIDES (MPS)
Sulphate Free Acidic MPS
1. Hyaluronic Acid
2. Chondroitin
Sulphate Containing Acid MPS
1. Keratan Sulphate
2. Chondroitin Sulphates
3. Heparin
4. Heparitin Sulphate
Blood group

24. Acidic Sulphate Free MPS
1. Hyaluronic Acid
2. Chondroitin

25. 1. Hyaluronic Acid:
• composed of repeating units of N-acetylglucosamine and
D-Glucuronic acid.( β 1-4 and β 1-3)
β 1-4
β 1-3
25

26. Hyaluronic Acid
Distributed widely throughout
• connective, epithelial, neural tissues
• synovial fluid
• skin
Main component of extracellular matrix
• Its primary function is
to bind and absorb water molecules
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27. Hyaluronidase
Hyaluronidase
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28. Hyaluronidase
• Enzyme catalyses the de-polymerisation of hyaluronic acid
• Diffusion of materials into tissue spaces
• Enzyme is known as Spreading Factor
Biomedical Importance
• The invasive power of some pathogenic organisms may
be increased because they secrete hyaluronidase.
28

29. Hyaluronidase enzyme digests hyaluronic Acid
E.g: S. Aureus produce hyaluronidase
29

30. 2. Chondroitin
• Same structure as Hyaluronic acid
• composed of repeating units of N-acetylgalactosamine
and D-Glucuronic acid.( β 1-4 and β 1-3)
β 1-4
β 1-3
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31. 2. Chondroitin
• Major component of the human extracellular matrix,
• linking together sugar and protein molecules
• Maintain the structural integrity of tissue.
• Found in cornea and cranial cartilages
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32. 2. Chondroitin
• A form of a complex carbohydrate,
Giving it shock and water-absorbing capabilities
Allowing joint/bone movement without friction
• Stimulating regeneration of cartilage, which is the
connective tissue that cushions the ends of bones within
joints
• Loss of chondroitin from cartilage is a major cause of
osteoarthritis that degenerates joints.
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33. Sulphate Containing Acid MPS
1.Keratan Sulphate
2.Chondroitin Sulphates
3.Heparin
4.Heparitin Sulphate
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34. 1. Keratan Sulphate (Kerato Sulphate)
• Are large, highly hydrated molecules
• which in joints can act as a cushion to absorb mechanical
shock.
• Found in the cornea, cartilage and bone
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35. Keratan Sulphate
•Keratan Sulphate I
•Keratan Sulphate II

36. Keratan Sulphate I
N-acetylglucosamine is linked to a protein via the side-chain N
of an Asparagine residue in a particular amino acid sequence.
H O
OH
HN
H
H
HNH
OH
CH2OH
H
C CH3
O
C CH2 CH
O HN
C
HN
O
HC
C
HN
HC
R
O
C
R
O
Asn
X
Ser or Thr
N-acetylglucosamine
Initial sugar in N-linked
glycoprotein oligosaccharide
36
H2-O-SO3

37. Keratan Sulphate II
N-acetylglucosamine link to a protein via a glycosidic bond
between a sugar residue and a Serine or Threonine OH.
H O
OH
O
H
HNH
OH
CH2OH
H
C CH3
O
-D-N-acetylglucosamine
CH2 CH
C
NH
O
H
serine
residue
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H2-O-SO3

38. 1. Keratan Sulphate (Kerato Sulphate)
Keratan SO4 I
• Occurs in cornea
• N-glycosidic bonding
(linkage) is between
N-acetyl glucosamine and
Asparagine residue of
the Protein
Keratan SO4 II
• Occurs in skeletal tissues
• O-glycosidic bonding
(linkage) is between
N-acetyl glucosamine and
OH groups on serine and
threonine residues of the
protein.
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39. 2. Chondroitin Sulphates
• Principal MPS in the ground substance of mammalian
tissues and cartilage
• Occur in combination with proteins, called
Chondroproteins
• Composed of N-acetyl galactosamine with either
Glucuronic acid or Iduronic acid
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40. Chondroitin Sulphates
N-acetyl galactosamine with either Glucuronic acid or Iduronic acid
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41. 2. Chondroitin Sulphates
• Based on the
(a) Uronic acid (Glucuronic, Iduronic)
(b) Sulphates (position at C4 and C6)
• Chondroitin Sulphates A
• Chondroitin Sulphates B
• Chondroitin Sulphates C
• Chondroitin Sulphates D

42. Chondroitin Sulphates (SO4)
C4
C4
C6
N-acetyl galactosamine
(SO4)
42

43. Chondroitin
SO4
Present Structure
(repeating units of N-acetyl-D
Galactosamine)
Position of SO4 at
galactosamine
A
cartilages,
adult bone,
cornea
with D-Glucuronic acid C4
B
(Dermatan
sulphate)
β-Heparin
skin,
cardiac
valves,
tendons
With L-Iduronic acid
C4
C
Cartilage,
tendons with D-Glucuronic acid C6
D
cartilage of
shark D-Glucuronic acid
C6 , it has a second SO4
attached probably
at C2 or C3 of acid43

44. • A polymer of repeating disaccharide units of
Glucosamine + Glucuronic acid or Iduronic acid
• 90 % residues are L-Iduronic acid
• Sulfate on C2 of Iduronic acid
• Sulfate on C2 and C6 of Glucosamine
3- Heparin (α-Heparin)
44

45. 3-Heparin (α-Heparin)
• An anticoagulant
• Mainly produced by Mast cells of liver
• Found in
Lungs
Thymus
Spleen
Walls of large arteries
Skin
Blood (small quantities)
Heparin antagonist: Protamines, inhibits antithrombin III
•Deficiency cause widespread clot
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46. Heparin
• Strongly acidic due to Sulphuric groups
• occurs in combination with proteins as Proteoglycans.
• The protein molecule of heparin proteoglycan is unique,
consisting mainly Serine and Glycine residues
• 2/3 of the serine residue contain GAG chains
• Linkage with protein molecule is usually Gal N with Serine
sometimes with threonine.
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47. 4. Heparitin Sulphate
• Structure similar to heparin
• Unlike heparin, its predominant uronic acid is
• D-Glucuronic acid
• Present on cell surfaces as proteoglycan and is
extracellular.
• Negligible anticoagulant activity
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49. 49

50. III. Neutral MPS
• Blood Group

51. III. Neutral MPS
Blood group substances:
These contain peptides or amino acids and carbohydrates.
Four monosaccharides are found in all types of blood group
substances
• Galactose
• Fucose (6-deoxy-L-galactose)
• Galactosamine (acetylated)
• Glucosamine (acetylated)
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52. • The precursor to the ABO blood group antigens, present in
people of all common blood types, is called the H antigen.
• The specificity of the H antigen is determined by the
terminal disaccharide Fucose- Galactose
• Watkins and Morgan discovered that the
ABO epitopes were conferred by sugars,
• N-Acetylgalactosamine for the A-type
• Galactose for the B-type
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53. H antigen
• on RBCs, encoded by the H(FUT1) gene,
• Fucosyltransferase
• Adds fucose to a precursor oligosaccharide chain
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54. https://en.wikibooks.org/wiki/Structural_Biochemistry/Carbohydrates/Blood_Type
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57. III. Neutral MPS
Structure of blood groups—ABO system
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59. HETEROPOLYSACCHARIDES (HETEROGLYCANS)—
MUCOPOLYSACCHARIDES (MPS)
• They are essential components of tissues, present either in
free form or in combination with proteins.
• Carbohydrate content varies.
• Carbohydrate is > 4 per cent, called Mucoproteins
• Carbohydrate is < 4 per cent, called as Glycoproteins
59

60. 60
Reference:
Textbook Medical Biochemistry by Chatterjea,
Eight Edition, Chapter 3
https://www.amazon.com/Textbook-Medical-Biochemistry-M-D-
Chatterjea/dp/9350254840

61. 61
Reference:
Textbook Medical Biochemistry by Chatterjea,
Eight Edition, Chapter 3
https://www.amazon.com/Textbook-Medical-Biochemistry-M-D-
Chatterjea/dp/9350254840