This document summarizes polysaccharides and glycans. It discusses homopolysaccharides including fructosan, galactosan, and glucosans such as starch and glycogen. Starch is made of amylose and amylopectin and forms helical structures with iodine. Cellulose is composed of beta-glucose units linked by beta-1,4 bonds, forming long straight chains strengthened by hydrogen bonds. Glycosaminoglycans discussed include hyaluronic acid, chondroitin sulfate, keratin sulfate, dermatan sulfate, and heparan sulfate. Proteoglycans are composed of core proteins with covalently linked glycosaminoglycan side chains. They

1. Chemistry of Polysaccharides
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2. Classification of carbohydrates
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3. Polysaccharides or glycans
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4. Homopoysaccharides
Homo polysaccharides
Fructosan Galactosan
e.g. Inulin e.g. Agar
Glucosans
e.g. Starch
Glycogen
Cellulose
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5. Glucosans /Glucans
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6. Glycogen
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7. 2) Starch (Storage Polysaccharide)
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8. Components of Starch
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9. Starch
Suspensions of Amylose
in water adopt a helical
conformation
Iodine (I2) can insert in
the middle of the Amylose
helix to give a blue color
that is characteristic and
diagnostic for starch
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10. 3) Dextrins
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11. 4) Dextrans
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12. 5) Cellulose (Structural Polysaccharide)
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13. Cellulose
Cellulose consists of β -D-glucopyranose units linked by β 1 →4
bonds to form long, straight chains strengthened by cross-linking
hydrogen bonds.
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14. Cellulose- Digestion
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15. Significance of Cellulose
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16. Chitin- Structural Polysaccharide
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17. Inulin (Fructosan) Storage polysaccharide
Jerusalem artichoke
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18. Uses of Inulin
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19. Agar (Galactosan)
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20. Heteropolysaccharides/ Mucopolysaccharides
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21. Occurrence: synovial fluid, ECM of loose connective tissue. Serves as a lubricant and shock absorber.
Hyaluronic acid is unique among the GAGs because it does not contain any sulfate and is not found covalently attached to proteins. It
Hyaluronic acid polymers are very large (100 - 10,000 kDa) and can displace a large volume of water.
Specific Glycosaminoglycans of Physiological
Significance
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22. Occurrence: cartilage, tendons, ligaments, heart valves and aorta.
It is the most abundant GAG.
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23. Glycosaminoglycans of physiological
Significance
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24. Glycosaminoglycans of Physiological
Significance
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25. Neutral Mucopolysaccharides
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26. Proteoglycans (mucoproteins)
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27. Proteoglycan Monomer
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28. Structure of Proteoglycan Monomer
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29. Proteoglycan Aggregates
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30. Proteoglycan Aggregates
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31. Functions of Proteoglycans
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32. Functions of Proteoglycans(Biophysical Contd.)
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33. Functions of Proteoglycans
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34. Summary
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