Carbohydrates, Educational Platform.pptx

This is about Carbohydrates detailed ppt

1. Carbohydrate By Dr. Muhammad Nabi Pharm-D, R.Ph, M.Phil Biochemistry M.Phil Pharmacology Ph.D Pharmacology

2. Carbohydrates Carbohydrates are polyhydroxy aldehydes or ketones, or substances that yield such compounds on hydrolysis. The name carbohydrate which is signifies as hydrate of carbon. Most abundant bio-molecules on Earth. Photosynthesis converts more than 100 billion metric tons of CO2 and H2O into cellulose and other plant products/ year. S ugar and starch are a dietary staple in most parts of the world T he oxidation of carbohydrates is the central energy-yielding pathway in most non-photosynthetic cells . Insoluble carbohydrate polymers serve as structural and protective elements in the cell walls of bacteria and plants and in the connective tissues of animals. Many , but not all, carbohydrates have the empirical formula (CH2O)n S ome also contain nitrogen, phosphorus, or sulphur. C arbs includes sugars are also called saccharides.(saccharides = sugar) Abdullah Danish, Educational Platform

3. Foods high in carbohydrates Sweets Soft drinks Breads Beans, peas Cereals, Rice, maize, barley, wheat, corn apricot, dates, blueberry, banana , grapes, apple, orange , pineapple, strawberry and watermelon etc   macaroni, spaghetti, potato, carrot Abdullah Danish, Educational Platform

4. Examples of Carbohydrates Glucose: major metabolic fuel of mammals Glycogen: storage; in animals Starch: Storage; in plants Cellulose: structure; in plants; in paper Chitin: stucture ; in Arthropods Ribose: RNA, ATP, NAD Deoxyribose : DNA lactose: Milk Abdullah Danish, Educational Platform

5. Functions Carbohydrates have six major functions within the body: Providing energy and regulation of blood glucose Sparing the use of proteins for energy Breakdown of fatty acids Biological recognition processes Flavor and Sweeteners Dietary fiber Abdullah Danish, Educational Platform

6. Carbohydrate is necessary for the regulation of nerve tissue and is the source of energy for the brain. Some carbohydrates are high in fibre , which helps prevent constipation Structural components Carbohydrates are also important for the correct working of our brain, heart and nervous, digestive and immune systems.  Polysaccharides: storage of energy (e.g., starch and glycogen), structural components (e.g., cellulose in plants and chitin in arthropods). ribose in coenzymes (e.g., ATP, FAD, and NAD) and the backbone of RNA. Deoxyribose: component of DNA. Heparin is used to treat and prevent blood clots from forming, especially in the lungs and legs. Abdullah Danish, Educational Platform

7. CLASSIFICATION Three major classes of carbohydrates: 1. Monosaccharaides, 2. Oligosaccharides , and 3. Polysaccharides Abdullah Danish, Educational Platform

8. 1. Monosaccharides ( The word “saccharide” is derived from the Greek sakcharon , meaning “sugar”). Monosaccharides , or simple sugars, consist of a single polyhydroxy aldehyde or ketone unit. Depending upon the functional, Aldoses (CHO) or Ketoses (C=O) The most abundant monosaccharide D-glucose, sometimes referred to as dextrose. Monosaccharides of more than four carbons tend to have cyclic structures. Empirical formula (CH2O)n where n=3 or some large number. Abdullah Danish, Educational Platform

9. The monosaccrides are white crystalline solids, very soluble in water, most have sweet taste . Abdullah Danish, Educational Platform

10. Oligosaccharides Oligosaccharides consist of short chains condensation products of two and ten of monosaccharide units, or residues, joined by covalent linkages called glycosidic bonds . E.g. most common sucrose, maltose and lactose. The most abundant are the disaccharides, with two monosaccharide units.e.g maltose Typical is sucrose (cane sugar), which consists of the six-carbon sugars D-glucose and D-fructose. All common monosaccharides and disaccharides have names ending with the suffix “- ose .” In cells, most oligosaccharides consisting of three or more units do not occur as free entities but are joined to non-sugar molecules (lipids or proteins) in glycoconjugates . Abdullah Danish, Educational Platform

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12. Polysaccharides The polysaccharides are sugar polymers containing more than 20 or so monosaccharide units, and some have hundreds or thousands of units. Some polysaccharides, such as cellulose, are linear chains. Others are glycogen and starch. Abdullah Danish, Educational Platform

13. Classifications of polysaccharides Homopolysaccharides : On hydrolysis they yield only one type of monomer which may be a pure monosaccharide or complex monosaccharide e.g. B (1-4) linked N-Acetyl glucosamine. Heteropolysaccharides : This is a very large group containing two or more types of monosaccharaides derivatives. They are further subdivided into : A. Glycos -amino- glycans (GAGs) These are also called mucopolysaccharides and include: Hyaluronic acid, Heparin, Blood group polysaccharides & serum mucoids . They also contain acid groups . B. Glycoconjugates : Class of carbohydrates covalently linked with other chemical species such as proteins and lipids. They include proteoglycans, glycoproteins, and glycolipids. Abdullah Danish, Educational Platform

14. C: Mucilage: They form viscous solution (gel) which is occasionally sticky. They include: Agar (Microbial culture), Vegetable gums (Fruit pulp Citrus fruits), & Pectin (plants). D . Derived Carbohydrates: These are derived from carbohydrates by various chemical reactions. These include oxidation products (sugar acids) such as: Gluconic Acid, Glucuronic Acid & Glucaric Acid etc. Reduction Products i.e. Poly Hydroxy Alcohol e.g. Glyceral and deoxy sugar (2- deoxyribose ), amino sugar : glucosamine . Oxidation is the  gain  of oxygen. Reduction is the  loss  of oxygen. Abdullah Danish, Educational Platform

15. Exceptions General formula: C m (H 2 O) n Carbohydrates with different formula Uronic acids: C 6 H 9 O 7 Fucose : C 6 H 12 O 5 Non carbohydrates with formula of carbohydrates Formaldehyde: CH 2 O Inositol:  C 6 (H 2 O) 6 Abdullah Danish, Educational Platform

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17. Biomedical Importance Most abundant dietary source of energy . Brain cells and RBCs are almost wholly dependent on carbohydrates as the energy source.  Also serve as storage form of energy –Glycogen. Carbohydrates are precursors for many organic compounds (fats, amino acids). Participate in the structure of cell membrane & cellular functions (cell growth, adhesion and fertilization). Certain carbohydrate derivatives are used as drugs, like cardiac glycosides / antibiotics. (aminoglycosides , macrolides) DM ( diabetes mellitus) Abdullah Danish, Educational Platform

18. Carbohydrate Part #2 By Dr. Muhammad Nabi Pharm-D, M.Phil Biochemistry M.Phil Pharmacology Ph.D Pharmacology

19. ISOMERISM IN MONOSACCHARIDES Compounds that possesses the same molecular formula & different structural formula are called isomers and the phenomena is known as isomerism. Glucose , Fructose, Mannose , & Galactose all have same chemical formula but different structural formula and therefore these are isomers of each other . Isomerism in Monosaccharides are of several types

20. Stereoisomerism: (stereo= having three dimensions) Two or more monosaccharides having the same structure i.e. same linkage between atoms but different from each other in configuration i.e. Arrangement of atoms in space .

21. Enantiomers : These are pairs of stereoisomers that are mirror images of each other in regard to asymmetric c-atoms. An asymmetric C- atom or Chiral Carbon is a C-atom that is attached to four different types of atoms or group of atoms . D and L depends on the on last asymmetric carbon atom. D Glucose = “D” refers right hand side of the hydroxyl (OH) side chain. L Glucose = “L” refers left hand side of the hydroxyl (OH) side chain . Most of the sugar is exist in D form.

22. Anomers : These are two isomers that differ in configuration around the anomeric carbon atom i.e the carbon atom of the carbonyl group which is carbon No 1 and carbon No 2 in ketoses. The two types of anomers are called alpha and beta anomers . They are not mirror images of each other. Type is based on the position of the C-1 OH Alpha glycosidic bond OH is below - linkage between a C-1  OH and a C-4 OH Beta glycosidic bond OH is above - linkage between a C-1  OH and a C-4 OH

23. Epimers : These are two isomers which differ in configuration around one specific carbon atom other than carbon atom of carbonyl group. Glucose & Galactose differ from each other only in the position of (OH) at C-4. They are called carbon-4 epimers . Isomers in which orientation of –H and –OH is different at a particular carbon.

24. Optical Isomerism: The enantiomeric carbon monosaccharides by virtue of their content asymmetric carbon atoms can rotate the plane - polarized light either to right or to the left. Those monosaccharides that rotate this light to right are called dextrorotatory and are designated (+) type clockwise. Those rotating this light to left are called levorotatory and are designated (-) type anticlockwise.

25. Pyranose & Furanose Isomerism : The ring structures of monosaccharides may be similar to either Pyran OR Furan and accordingly monosaccharide is said to occur in pyranose or furanose forms.

26. Fischer projection The Fischer projection is a two-dimensional representation of a three-dimensional organic molecule by projection . Haworth projectionsHaworth projections A Haworth projection is a common way of representing the cyclic structure of monosaccharides with a simple three-dimensional perspective.

27. CHEMICAL REACTIONS OF MONOSACCHARIDES Chemical properties depends upon the presence of various groups in monosaccharides i.e. aldehyde ,ketone & hydroxyl groups. 1 : Reaction with Hydrazines to form Osazones : • Osazones which are actually phynylosazones which are yellowish crystalline compounds and are produced as a result of heating sugar solutions with phenylhydrazines . • Glucose react with three molecules of phenylhydrazine to form glucasazone . 2 : Reduction to form sugar alcohols : • Both aldoses & ketoses may be reduced at their aldehyde and ketone groups to form the corresponding poly hydroxy alcohols. • Glucose → Sorbital , Mannose → Mannitol • Galactose → Galactitol ( Dulcitol ) • Fructose → Sorbital & Mannitol • Ribose→ Ribitol , Glyceraldehyde→ Glycerol • Dihydroxyacetone → Glycerol

28. CHEMICAL REACTIONS OF MONOSACCHARIDES 3. Oxidation to produce sugar acids: • When oxidize under proper conditions the aldoses gives rise to the following three types of sugar acids. • Gluconic Acid (at C-1) • Glucuronic Acid (at C-6) • Glucaric Acid (at C-1 & C-6) 4: Reducing Action Of Sugar In Alkaline Solution: • Sugars in alkaline solutions are very powerful reducing agents and the sugars are oxidized to complex mixture of acids . e.g. C u +, A g + etc. • The reducing action of sugars i.e. benedict's solution and Barfoed’s solution have been employed for both qualitative and semi qualitative determination of reducing sugars especially glucose in urine.

29. 5: Action Of Acids: • Monosaccharides are resistant to action of hot dilute mineral acids. Strong acids remove water from sugar converting them to furfurals which condense with phenol to give characteristics colored products. • C5 H10 O5 → C5 H4 O2 + 3H2O • Ribose → Furaldehyde → water removed • This reaction is the basis of Molisch’s test for carbohydrates. 6 : Action Of Basis: • Dilute basis solution at low temperature can bring about rearrangement of groups around anomeric C-Atom and its adjacent C-atoms . e.g. Glucose can be changed to fructose and mannose.

30. 7: Formation Of Glycosides: Glycosides are compounds in which a carbohydrate residue such as glucose is attached by Acetyl linkage at anomeric carbon atom to an alcoholic residue called aglycone which is non carbohydrate . 8: Formation Of esters: • The OH group of sugar may be esterified to form esters such as phosphate acetates, propionates etc. • Sugar phosphate backbone form structural framework of nucleic acid (DNA & RNA ). • Hexose + Phosphate = Hexose phosphate • Ribose+ Phosphate = Ribose phosphate

31. 9: Formation Of Amino Sugars : • A hydroxyl group of monosaccharides can be replaced by an amino group forming an amino sugar .e.g . • D – glycose amine = Hyaluronic Acid • D – galactose amine = Chondroitin • D – mannose amine = Mucoprotein • Being derived from hexoses they are called hexose amine. Amino sugars are also present in antibiotics . e.g. Erythromycin. 10 : Fermentation: • Breakdown of sugars by bacteria and yeast using a method of anaerobic respiration. • Glucose→ Yeast or Bacteria→ 2 Ethanol+2 carbon dioxide • C6 H12O6 → 2 (C2H5OH) + CO2

32. PHARMACEUTICAL IMPORTANCE OF CARBOHYDRATES 1. Glucose : Glucose is used to treat very low blood sugar level i.e. hypoglycaemia most often in people in diabetes mellitus .Glucose is also used to provide carbohydrate calories to a person who cannot eat because of illness trauma etc. ( primary source of energy ). 2 . Component Of Cell Membrane: Carbohydrates are covalently linked to proteins (glycoproteins) lipids (glycolipids) are parts of cell membrane and function as adhesion. 3 . Pectin: is the heteropolysaccaride Pectin is used to reduced blood cholesterol level and gastrointestinal disorders. 4 . Agar: Microbial culture → nutrient agar is a nutrient medium most effectively used for the cultivation of microorganism supporting growth of a wide range of non fastidious organism and blood ager is most appropriate for human related organism in clinic practice. 5 . Chondroitin Sulphate & Glucosamine Sulphate : For joints disorder treatments such as osteoarthritis. 6 . Dextran: It is used to treat hypovolemia or hypovolemic shock (decrease volume of circulating blood plasma) that can result from surgery, trauma.

33. 7. Inulin : (Polymer of fructose) Inulin is used to measure kidney function by determining glomerular filtration rate ( GFR) which is volume of fluid filtered from glomerular capillaries into bowman capsule per unit time . 8 . Heparin: Heparin act as an anticoagulant , prevent formation of clots . 9 . Mannitol : It is osmotic diuretic used to reduce swelling and pressure inside the eye all around the brain. 10 . Lactose: Used as excipient in tablets. 11 . Ribose & Deoxyribose : Form structure of hereditary material such as DNA &RNA. 12 . Aminoglycosides: They are broad spectrum bactericidal antibiotics commonly prescribe for children. 13 . Hyaluronic Acid : Used in in topical serum, eye drops & injections. Also form structural bases of joints, skin & aqueous humor of eye. 14 . Gums: Used as foods as well as suspension preparations. 15 . Glycogen & Starch: Energy storage → Glycogen (animals) Starch (Plants).

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