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Carbohydrate Chemistry

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Chemistry of Carbohydrates for medical, para medical, Science students.

Chemistry of Carbohydrates for medical, para medical, Science students.

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  • it is a elaboration and useful presentation. would you please share this ppt to me on pradipta_t2@yahoo.com
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  • good presentaion sir pls share this ppt my mail id aravindh.dpi007@gmail.com
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  • Hi sir, Its really good and more informative presentation.....if u dont mind can share it to me on jaideep.deore@gmail.com
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  • Hi, it's a good presentation with easy to understand slides.. Would you mind sharing it? my email ID shambhu.aralaguppe@yahoo.com
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  • 1. 1 of 91 Carbohydrate Chemistry Ashok Katta Dept. Of Biochemistry, DS Medical College, Perambalur
  • 2. 2 of 91 Ashok KattaCarbohydrate Chemistry Introduction The word carbohydrates is derived from their general formula [C(H2O)]n that makes them seem to be “hydrates of carbon.” The terms carbohydrate and saccharide are closely related. The most abundant carbohydrates are polysaccharides. Most important carbohydrate in the body - Glucose. “Saccharide” comes from the word for table sugar in several languages: sarkara in Sanskrit, sakcharon in Greek, saccharum in Latin.
  • 3. 3 of 91 Ashok KattaCarbohydrate Chemistry Importance of Carbohydrates Distributed widely in nature Key intermediates of metabolism (sugars) Structural components of plants (cellulose) Central to materials of industrial products: paper, fibers Key component of food sources: sugars, flour, vegetable fiber
  • 4. 4 of 91 Ashok KattaCarbohydrate Chemistry Definition Carbohydrates may be defined as polyhydroxy aldehyde or polyhydroxy ketone or compound that yield these derivatives on hydrolysis. C C CH2OH =OH H OH CHO H CH OH CH OH D - Glucose CH2OH C CH2OH =O CHO H CH OH CH OH D - Fructose
  • 5. 5 of 91 Ashok KattaCarbohydrate Chemistry Glycogen α-Amylase D - Glucose
  • 6. Functions of Carbohydrates
  • 7. 9 of 91 Ashok KattaCarbohydrate Chemistry Some Additional Terms Aldose A carbohydrate that contains an aldehyde group Ketose Triose Tetrose Aldopentose Ketohexose A carbohydrate that contains a ketone group A carbohydrate having three carbons A carbohydrate having four carbons A five-carbon carbohydrate that contains aldehyde group A six-carbon carbohydrate that contains a ketone group
  • 8. Monosaccharide Oligosaccharide Polysaccharide Classification and Nomenclature Carbohydrates are broadly classified in to three groups…. C A R B O H Y D R A T E S
  • 9. Classification and Nomenclature Carbohydrates Monosaccharide Functional group Number of carbon atoms Oligosaccharide Di- saccharide Tri- saccharide Tetra- saccharide Polysaccharide Homopoly- saccharide Hetropoly- saccharide Aldoses e.g Glucose Trioses Ketoses e.g Fructose Tetroses Pentoses Hexoses Heptoses Maltose Lactose Sucrose Raffinose Stachyose Starch Dextrin Glycogen Cellulose Inulin Hyaluronic acid Heparin Chondroitin sulfate Dermatan Sulfate Keratan Sulfate
  • 10. 12 of 91 Ashok KattaCarbohydrate Chemistry Monosaccharides One Sugar
  • 11. 13 of 91 Ashok KattaCarbohydrate Chemistry Monosccharides are sub divide into different groups. Depending upon the functional…… Aldoses (CHO) or Ketoses (C=O) Depending upon the number of carbon atoms they possess, Trioses (3C) Tetroses (4C) Pentoses (5C) Hexoses (6C) and Heptoses (7C)
  • 12. 14 of 91 Ashok KattaCarbohydrate Chemistry Classification of Monosaccharides No. of Carbon Type of sugar Aldoses Ketoses 3 TRIOSES Glyceraldehydes Dihydroxyacetone 4 TETROSES Erythrose Erythrulose 5 PENTOSES Ribose, Xylose Ribulose, xylulose 6 HEXOSES Glucose, Galactose Fructose 7 HEPTOSES Glucoheptose Sedoheptulose
  • 13. 15 of 91 Ashok KattaCarbohydrate Chemistry TYPES EXAMPLE IMPORTANCE Trioses Glyceraldehyde, Dihydroxyacetone Intermediates of glycolysis, Precursor of glycerol (for lipid synth) Tetroses D-Erythrose Intermediates of carbohydrate metabolism Pentoses D-Ribose Structural element of nucleic acid, RNA, co-enzymes. Hexoses D-Glucose Main sugar of the body. D-Fructose Converted to glucose & utilized by the body. D-Galactose Synthesized in mammary gland to make the lactose of milk. D-Mannose Constituent of glycoprotein, glycolipids
  • 14. 16 of 91 Ashok KattaCarbohydrate Chemistry Oligosaccharides Contains 2 to 10 monosaccharide units. Joined together by a specific bonds called glycosidic bond. On hydrolysis, they gives 2 to 10 molecules of simple sugar units. They are subdivide based on the number of monosaccharide units. Disaccharides Trisaccharide Tetrasaccharide Pentasaccharide
  • 15. 17 of 91 Ashok KattaCarbohydrate Chemistry Classification of Oligosaccharides No “C” Examples Type of monosaccharide Disaccharides 2 Maltose Glucose + Glucose Lactose Glucose + Galactose Sucrose Glucose + Fructose Trisaccharides 3 Raffinose Glu + Fruc + Galactose Tetra saccharides 4 Stachyose 2 Galactose + Glucose + Fructose Penta saccharides 5 Verbascose 3 Galactose + Glucose + Fructose
  • 16. 18 of 91 Ashok KattaCarbohydrate Chemistry Polysaccharides
  • 17. 19 of 91 Ashok KattaCarbohydrate Chemistry Polysaccharides Contains many (more than 10) sugar units. They have high molecular weight and are sparingly soluble in cold water. They are also called as Glycans. They may be either liner or branched in structure. They are not sweetish and do not exhibit any of the properties of aldehyde or ketone group.
  • 18. 20 of 91 Ashok KattaCarbohydrate Chemistry POLYSACCHARIDES Homopolysaccharides Starch Glycogen Dextrins Hetropolysaccharides Agar Pectins Glycosaccharide
  • 19. 21 of 91 Ashok KattaCarbohydrate Chemistry Structural functional relationship of Monosaccharide STRUCTURE OF MONOSACCHRIDES PHYSICAL PROPERTIES CHEMICAL PROPERTIES C C CH2OH =OH H OH CHO H CH OH CH OH
  • 20. 22 of 91 Ashok KattaCarbohydrate Chemistry Structure of Monosaccharide Glucose is the most important physiological and biomedical monosaccharide. It can be represented in… The straight chain structure Ring /cyclic structure Boat and chair form.
  • 21. 23 of 91 Ashok KattaCarbohydrate Chemistry The straight chain structure C C H2OH =O H H OH CHO H CH OH CH OH C
  • 22. 24 of 91 Ashok KattaCarbohydrate Chemistry Ring /cyclic structure (Haworth projection) C R =OH + R’HO C R OHH OR’ Aldehyde Alcohol Hemiacetal C R =O R” + R’HO C R OHOR’ R’’ Ketone Alcohol Hemiketal
  • 23. 25 of 91 Ashok KattaCarbohydrate Chemistry
  • 24. 26 of 91 Ashok KattaCarbohydrate Chemistry Haworth projection formula of glucose O C O CH2OH OH OH OH OH C C CH2OH OHH H OH CHO H CH OH CH O Pyranose α-D-Glucoyranose (Fisher structure) α-D-Glucoyranose (Hworth structure) C C CH2OH =OH H OH CHO H CH OH CH OH D - Glucose
  • 25. 27 of 91 Ashok KattaCarbohydrate Chemistry Haworth projection formula of fructose OCH2OH CH2OH OH OH OH OC C CH2OH C CH2OH H OH CHO H CH OH CH O CH2OH C CH2OH =O CHO H CH OH CH OH D - Fructose Furanose α-D-Fructofuranose (Fisher structure) α- D-Fructofuranose (Hworth structure)
  • 26. 28 of 91 Ashok KattaCarbohydrate Chemistry Chair and boat from of D- glucose O CH2OH OH OH OH OH
  • 27. 29 of 91 Ashok KattaCarbohydrate Chemistry Properties of Monosaccharides Isomerism Chemical reactions
  • 28. 30 of 91 Ashok KattaCarbohydrate Chemistry Isomerism The compounds possessing same molecular formula and different structures are referred as Isomers. The phenomenon of existence of isomer is called Isomerism. Structural Isomerism Stereoisomerism
  • 29. 31 of 91 Ashok KattaCarbohydrate Chemistry Structural Isomerism same molecular formulae but differ in their structures. Aldose-Ketose Isomerism Glucose and fructose isomers of each other. They are having same molecular formula C6H12O6 But differ in their structural formula.
  • 30. 32 of 91 Ashok KattaCarbohydrate Chemistry Aldose-Ketose Isomerism C C CH2OH =OH H OH CHO H CH OH CH OH D - Glucose CH2OH C CH2OH =O CHO H CH OH CH OH D - Fructose C6H12O6
  • 31. 33 of 91 Ashok KattaCarbohydrate Chemistry Stereoisomerism same molecular formula, structures but differ in their configuration. Asymmetric (Chirl) carbon allow the formation of stereoisomerism. Types of stereoisomerism of glucose are…… D and L isomerism Optical isomerism Epimerism Anomerism
  • 32. 34 of 91 Ashok KattaCarbohydrate Chemistry L - Glyceraldehyde C C CH2OH =OH H OH C C CH2OH =OH HO H C C CH2OH =OH H OH CHO H CH OH CH OH C C CH2OH =OH HO H CH OH CHO H CHO H D and L isomerism (enantiomer) D - Glucose L - Glucose D - Glyceraldehyde
  • 33. 35 of 91 Ashok KattaCarbohydrate Chemistry D and L isomerism (enantiomer) D and L isomers are mirror images of each other. These two forms are called Enantiomers.
  • 34. 38 of 91 Ashok KattaCarbohydrate Chemistry Optical isomerism Optical activity is the capacity of a substance to rotate the plane polarized light passing through it. When light rotate to right (clockwise) direction, that substance is said to be dextrorotatory (d) (+). When light rotate to left (anticlockwise) direction, that substance is said to be levorotatory (l) (-). When equal amount of d and l isomers are present, that mixture is said to be recemic / dl mixture.
  • 35. 39 of 91 Ashok KattaCarbohydrate Chemistry
  • 36. 40 of 91 Ashok KattaCarbohydrate Chemistry Epimerism Epimers are sugars which are differ with each other with respect to single carbon, other than anomeric carbon. Galactose and Mannose are the epimers of the glucose. They differ from the glucose with the respect of the C-4 and C-2 respectively.
  • 37. 41 of 91 Ashok KattaCarbohydrate Chemistry Epimers of glucose C C CH2OH =OH H OH CHO H CH OH CH OH D - Glucose C C CH2OH =OH HO H CHO H CH OH CH OH D - Mannose C C CH2OH =OH H OH CHO H CHO H CH OH D - Galactose
  • 38. 42 of 91 Ashok KattaCarbohydrate Chemistry Anomerism In solution glucose predominantly exist as closed chain structure. Because of cyclization of sugar, an additional asymmetric center is created at C-1 (anomeric carbon). This leads to formation of two isomers namely…. α- D-glucopyranose β- D-glucopyranose
  • 39. 43 of 91 Ashok KattaCarbohydrate Chemistry C C CH2OH OHH H OH CHO H CH OH CH O C C CH2OH HHO H OH CHO H CH OH CH O α- D - Glucose β - D - Glucose
  • 40. 44 of 91 Ashok KattaCarbohydrate Chemistry Mutarotation It is defined as “the change in the specific optical rotation representing interconversion of α and β forms of D-glucose to an equilibrium mixture.” Equi. mixtureα- D - Glucose β - D - Glucose Specific rotation [α]D = +112.2˚ Specific rotation [α]D = +52.7˚ Specific rotation [α]D = +18.7˚
  • 41. 45 of 91 Ashok KattaCarbohydrate Chemistry C C CH2OH OHH H OH CHO H CH OH CH O C C CH2OH HHO H OH CHO H CH OH CH O C C CH2OH =OH H OH CHO H CH OH CH OH D - Glucoseα- D - Glucose β - D - Glucose +112.2˚ +52.7˚ +18.7˚
  • 42. 46 of 91 Ashok KattaCarbohydrate Chemistry Chemical Properties of monosaccharides Some of the important chemical properties of monosaccharides are… Furfural formation Enolization Oxidation Reduction Osazone formation
  • 43. 47 of 91 Ashok KattaCarbohydrate Chemistry Sugar when treated with strong mineral acids like… Conc. Sulfuric acid (H2SO4) Conc. Hydrochloric acid (HCL) Conc. Nitric acid (HNO3) They undergoes dehydration loses 3 water molecules to form furfural derivatives. This is the basis for following reactions… Molisch’s test Seliwanoff’s test
  • 44. 48 of 91 Ashok KattaCarbohydrate Chemistry Fig. 2.10 Hydroxy methyl furfural CHO C CH2OH CH CH C O C C CH2OH =OH H OH CHO H CH OH CH OH D - Glucose Coloured complex Condense with phenolic componudconc acids 3 H2O
  • 45. 49 of 91 Ashok KattaCarbohydrate Chemistry When glucose is kept in alkaline solution for several hours, it undergoes isomerization to form D- fructose and D- mannose. This results in formation of a common intermediate – enediol. The process of shifting of hydrogen atom from one carbon atom to another to produce enediols is known as tautomerization.
  • 46. 50 of 91 Ashok KattaCarbohydrate Chemistry Alkaline solution Glucose Fructose Mannose Glucose
  • 47. C C CH2OH =OH H OH CHO H CH OH CH OH D - Glucose C C CH2OH =OH HO H CHO H CH OH CH OH D - Mannose D - Fructose C C CH2OH OHH OH CHO H CH OH CH OH Enediol CHOH C CH2OH =O CHO H CH OH CH OH H
  • 48. 52 of 91 Ashok KattaCarbohydrate Chemistry Enediols are good reducing agents. And forms basis of reducing property of sugars. Benedict’s test and Fehling’s test. CuSO4 Cu++ Cu+ 2Cu(OH) Cu2O Sugar Enediol Red ppt
  • 49. 53 of 91 Ashok KattaCarbohydrate Chemistry When glucose oxidizes under proper conditions the sugars may form: Monobasic Aldonic Acid: oxidation with Hydrobromous acid. Dibasic saccharic acids or Alderic acid: oxidation with nitric acid (HNO3). Monobasic Uronic acid: oxidised by specific enzymes.
  • 50. 54 of 91 Ashok KattaCarbohydrate Chemistry Formation of Aldonic acid D - glucose Gluconic acid Hydrobromous acid C C CH2OH =OH H OH CHO H CH OH CH OH COOH C CH2OH H OH CHO H CH OH CH OH Medical Importance Calcium gluconate (gluconic acid) used as source of calcium. These are given I.V. fluids rise the calcium levels.
  • 51. 55 of 91 Ashok KattaCarbohydrate Chemistry Formation of Saccharic acid D - glucose Glucosaccharic acid Nitric acid C C CH2OH =OH H OH CHO H CH OH CH OH COOH C COOH H OH CHO H CH OH CH OH
  • 52. 56 of 91 Ashok KattaCarbohydrate Chemistry Formation of Aldonic acid D - glucose Glucuronic acid Enzymatic C C CH2OH =OH H OH CHO H CH OH CH OH Medical Importance These are present in the heteropolysaccharides and glycoproteins. Involved in detoxification of benzoic acid, bilirubin & certain drugs C C COOH =OH H OH CHO H CH OH CH OH
  • 53. 57 of 91 Ashok KattaCarbohydrate Chemistry Both aldoses and ketoses may be reduced by enzymes to the corresponding polyhydroxy alcohols. The sugar alcohols function mainly as intermediates in the minor pathway of carbohydrate metabolism. Some of these alcohols are the followiing: Sorbitol Mannitol Dulcitol Ribitol
  • 54. 58 of 91 Ashok KattaCarbohydrate Chemistry D-Glucose D-Sorbitol D-Mannose D-Mannitol D-Fructose D-Sorbitol D-Galactose D-Dulcitol D-Ribose D-Ribitol Medical Importance Mannitol: It is used as an osmotic diuretic to reduce the cerebral oedema. Sorbitol: It is accumulates in the lenses of diabetic and produces cataracts.
  • 55. 59 of 91 Ashok KattaCarbohydrate Chemistry Only reducing sugars gives this test positive. The presence of free carbonyl (aldehyde or ketone) group in the molecule is essential for the osazone formation. Osazones are yellow crystalline derivatives of reducing sugars with phenylhydrazine and have a characteristic crystal structure which can be used for identification and characterization of different sugars having closely similar properties.
  • 56. 60 of 91 Ashok KattaCarbohydrate Chemistry Osazone formed from Glucose, Fructose and Mannose are identical because these are identical in their lower four carbon atoms. Non-reducing sugars like sucrose cannot form osazone due to the absence of a free carbonyl group. The Osazone crystals of some sugars are: Glucosazone – Needle shaped Maltosazone – Sunflower petals shaped Lactosazone – Powder puff of tennis ball shaped
  • 57. 61 of 91 Ashok KattaCarbohydrate Chemistry Why glucose, fructose, and mannose give same type of osazones D - glucose Phenyl hydrazine C C CH2OH =OH H OH CHO H CH OH CH OH H2N-NH-C6H5 C C CH2OH =H H OH CHO H CH OH CH OH N-NH-C6H5 Phenyl hydrazine H2N-NH-C6H5 C C CH2OH =H H CHO H CH OH CH OH = N-NH-C6H5 N-NH-C6H5 glucohydrozone Osazone
  • 58. 62 of 91 Ashok KattaCarbohydrate Chemistry D - glucose C C CH2OH =OH H OH CHO H CH OH CH OH C C CH2OH =OH HO H CHO H CH OH CH OH D - MannoseD - Fructose CH2OH C CH2OH =O CHO H CH OH CH OH
  • 59. 63 of 91 Ashok KattaCarbohydrate Chemistry Needle shaped crystals Glucosazone , Fructosazone Mannosazone Powder puff or tennis ball shaped Lactosazone Sunflower petals shaped Maltosazone
  • 60. 64 of 91 Ashok KattaCarbohydrate Chemistry When hydroxyl group on the anomeric carbon of a monosaccharides reacts with an OH group of another carbohydrate or non-carbohydrate leads to glycosides formation. The bonds joining the monosaccharides are called glycosidic or glycosyl bonds. There are two types of glycoside bonds: O-glycosidic bonds N-glycosidic bonds
  • 61. 65 of 91 Ashok KattaCarbohydrate Chemistry O- and -N type of Glycoside Bonds O-type Glycoside Bond N-Type Glycoside Bond
  • 62. 66 of 91 Ashok KattaCarbohydrate Chemistry Stretomycin (antibiotic) – used as drugs for the treatment of tuberculosis. Cardiac glycosides like digoxin and digitoxin are increase muscle contraction and used for treatment of the congestive heart failure. Anthacycline glycosides like Doxirubicin used to treat wide range of cancers. Ouabain inhibits Na-K ATPase and block the active transport of Na. Physiologically important glycosides
  • 63. 67 of 91 Ashok KattaCarbohydrate Chemistry Some derivatives of Monosaccharides are: Phosphoric acid ester of monosaccharides. e.g- G-1-P Amino Sugar. e.g- glucosamine Deoxy Sugars Sugar acids Sugar alcohols Derivatives of Monosaccharide
  • 64. 68 of 91 Ashok KattaCarbohydrate Chemistry Disaccharides DI Two Sugar
  • 65. 69 of 91 Ashok KattaCarbohydrate Chemistry Consists of two monosaccharide units held by glycosidic bond. They are crystalline, water soluble, and sweet taste. They subdivide based on presence or absence of free reducing group into… Reducing disaccharides with free aldehyde or keto gr Example – Maltose and Lactose Non reducing disaccharide without free aldehyde or keto gr Example - Sucrose Disaccharide
  • 66. 70 of 91 Ashok KattaCarbohydrate Chemistry It contains two moles of glucose units. They linked by α-(1-4) glycosidic linkage. It is a one of the reducing disaccharide, which has free functional group. Maltose
  • 67. 71 of 91 Ashok KattaCarbohydrate Chemistry Maltose O CH2OH OH OH OH O CH2OH OH OH OH O α- D - glucose α- D - glucose α (1→4) glycosidic bond
  • 68. 72 of 91 Ashok KattaCarbohydrate Chemistry It is present in the milk sugar. It contains one mole of galactose and one mole of glucose that are linked by β-(1-4) glycosidic linkage. It is also a reducing disaccharide. It hydrolyzed into galactose and glucose by the enzyme lactase in human and by β-D-galactosidase in bacteria. It is the source of carbohydrates in breast fed infants. Lactose
  • 69. 73 of 91 Ashok KattaCarbohydrate Chemistry Lactose O CH2OH OH OH OH O CH2OH OH OH OHO β - D - galactose β - D - glucose β (1→4) glycosidic bond
  • 70. 74 of 91 Ashok KattaCarbohydrate Chemistry It is commonly used table sugar and contributes some calories in the diet. It contains one mole of glucose and one mole of fructose that are linked by α-(1-2) glycosidic linkage. It is a non reducing disaccharide. It hydrolyzed into glucose and fructose by the enzyme Sucrase is also called as Invertase. Sucrose
  • 71. 75 of 91 Ashok KattaCarbohydrate Chemistry Sucrose O CH2OH OH OH OH O OCH2OH CH2OH OH OH OH D - glucose D - fructose α (1→2) glycosidic bond
  • 72. 76 of 91 Ashok KattaCarbohydrate Chemistry It is also contains two moles of glucose. They linked by α-(1-6) glycosidic linkage. It is derived from the digestion of starch & glycogen. It hydrolyzed to glucose in the intestinal tract by an enzyme called isomaltase. Isomaltose Trehalose It is also one of the disaccharide having two units of glucose linked by α-(1-1) glycosidic linkage. It is a non reducing disaccharide. Yeast and fungi are the sources of trehalose.
  • 73. 77 of 91 Ashok KattaCarbohydrate Chemistry Polysaccharides POLY Many Sugar
  • 74. 78 of 91 Ashok KattaCarbohydrate Chemistry Is reserve carbohydrate form in plants. e.g - potato A homopolymer composed of D-glucose units held by α- glycosidic bonds. It composed of two constituents, water soluble amylose (15-20%) and water insoluble amylopectin (80-85%). Starch
  • 75. 79 of 91 Ashok KattaCarbohydrate Chemistry Chemically, amylose is a long unbranched chain of 200- 1000 of D- glucose units linked by (1-4) bonds. Amylopectin, is a branched chain with (1-6) bonds at the branching points and (1-4) bonds everywhere else. Amylopectin contains few thousands of units looks like a branched tree. (20-30 units/ branch) Starch is hydrolyzed by the enzyme amylase to liberate dextrin and finally maltose and glucose units. Starch
  • 76. 80 of 91 Ashok KattaCarbohydrate Chemistry
  • 77. 81 of 91 Ashok KattaCarbohydrate Chemistry Partial hydrolysed products of starch by acids or enzymes. Starch is sequentially hydrolyzed through different dextrins and finally to maltose and glucose. The various intermediates are soluble starch, amylodextrins, erythrodextrins, and achrodextrins. All dextrins have free sugar groups and can show mild reducing property. Dextrins
  • 78. 82 of 91 Ashok KattaCarbohydrate Chemistry It is the major storage form of carbohydrate in animals, so it referred as animal starch. It is present in high concentration in liver, followed by muscle, brain etc. The structure of glycogen is similar to that of amylopectin with more no. of branches Glycogen
  • 79. 83 of 91 Ashok KattaCarbohydrate Chemistry
  • 80. 84 of 91 Ashok KattaCarbohydrate Chemistry Chief coenstituent of plant cell wall. An unbranched polymer of glucose linked by β-(1-4) glycosidic linkages. Since humans lack an enzyme cellulase that can hydrolyse β-(1-4) glycosidic linkages, cellulose cannot be digested and absorbed. has no food value unlike starch. Cellulose
  • 81. 85 of 91 Ashok KattaCarbohydrate Chemistry Cellulose, though not digested, has great importance in human nutrition. It is a major constituent of fibre, the non-digestable carbohydrate. The functions of dietary fibre include decreasing the absorption of glucose and cholesterol from the intestine, increasing the bulk of stool. Aids intestinal mobility acts as stool softener Prevent constipation. It reduces incidence of …. CVD Colon cancer diabetes Importance of Cellulose
  • 82. 86 of 91 Ashok KattaCarbohydrate Chemistry It is a polymer of D-fructose (fructosans). Linked together by β-(1-2) glycosidic linkage. It occurs in bulb of onion and garlic. It is a low mol. Wt (5000) polysaccharide easily soluble in water. It is not utilized by the body. It is used for assessing kidney function through measurement of glomerular filtration rate (GFR). Inulin
  • 83. 87 of 91 Ashok KattaCarbohydrate Chemistry MUCOPOLYSACCHARIDES Heteroglycans made up of repeating units of sugar derivatives, namely amino sugars and uronic acid. Commonly known as glycosaminoglycans. (GAGs) Acetylated amino groups, besides sulfate and carboxyl groups are generally present in their structure. Presence of sulfate and carboxyl groups contributes to acidity of the molecules, making them acid mucopolysaccharides. Some of them found in the combination with proteins to form mucoproteins or mucoids or proteoglycans. Mucoproteins may contain… up to 95% carbohydrate and 5% protein.
  • 84. 88 of 91 Ashok KattaCarbohydrate Chemistry MUCOPOLYSACCHARIDES Mucopolysaccharides are essential components of tissue structure. The extra cellular spaces of tissue (connective tissue, cartilage, skin, blood vessels, tendons) consist of collagen and elastin fibers embedded in a matrix or ground substance. The ground substance is predominantly composed of GAGs. The important mucopolysaccharides are… Hyaluronic acid Chondroitin 4-sulfate Heparin Dermatan sulfate and Keratan sulfate
  • 85. 89 of 91 Ashok KattaCarbohydrate Chemistry GAGs Composition Tissue Distribution Functions Hyaluronic acid D-Glucuronic acid, N-acetylglucosamine Connective tissue, synovial fluid, vitrous humor Lubricant, shock absorber, promotes wound healing Chondroti n sulfate D-Glucuronic acid, N-acetylglucosamine 4- sulfate Cartilage, bone, skin, blood vessel wall Maintain structure & shapes of tissues Heparin D-glucuronate 2- sulfate, N-sulfoglucosamine 6- sulfate Blood, lung, liver, kidney, spleen Acts as an anticoagulant Dermatan sulfate L-Iduronic acid, N- acetyl-galactosamine 4-sulfate Blood vessel valves, heart valves, skin Maintain the shapes of tissues Keratan sulfate D-Galactose, N-acetylglucosamine 6- sulfate Cartilage, cornea, connective tissues Keeps cornea transparent
  • 86. 90 of 91 Ashok KattaCarbohydrate Chemistry
  • 87. 91 of 91 Thanks For Listening Ashok Katta, 16 July 2014

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