Carbohydrates-Structure of carbohydrates, Types of CBH, Properties, and Function, Fuc
- 1. Shri Shankaracharya Mahavidyalaya, Junwani , Bhilai Dr. Sonia Bajaj (Head of Department) CARBOHYDRATES
- 2. SYNOPSIS Introduction Definition Function Classification of Carbohydrate Structure & Properties of Monosaccharide Structure & Properties of Disaccharide Structure & Properties of Polysaccharide Conclusion Reference 2
- 3. Introduction A carbohydrate is a biomolecule consisting of carbon, hydrogen and oxygen atom usually with the hydrogen oxygen atom ratio 2:1. The term carbohydrates was originally coin from for the class of compounds as most of them where 'hydrates of carbon' and could be represented by the general Formula C x (H2O)y. The term carbohydrates are also known as (saccharide or sugar) since many of those are of relatively small molecular weight having a sweet taste. They are widely distributed in both plants and animals. They are indispensable for living organisms serving as skeletal structure in plants and also in insects. They also occur as food reserve in the storage organ of plants and in the liver and muscles of animals. Plants are considerably richer in carbohydrates in comparison to the animals. 3
- 4. Definition Carbohydrates may be defined as polyhydroxyaldehyde or ketones or compounds which produces them on hydrolysis. 4
- 6. Structure & Properties of Monosaccharide “Mono’’ means one and “saccharon” means sugar. The monosaccharides often called simple sugar are compounds which posses a free aldehyde (–CHO)or ketone group (=CO) and two more hydroxyl group (-OH). Monosaccharides that contain an aldehyde group are referred to as an aldose. Those that contain a ketone group are referred to as a ketose. 6
- 7. PROPERTIES 1. Reaction with Carbonyl group:- Includes Reduction When monosaccharide reacts with sodium amalgam and water it produces polyhydric alcohol. 7
- 8. Oxidation a) Aldoses When glucose reacts with CuSO4, bromine water or silver oxide it produces monocarboxylic acid in which number of carbon atom does not changes 8
- 9. b) Phenylhydrazine reaction When Phenylhydrazine reacts with monosaccharide it gives osazone formation. 9
- 10. c) Hydroxyl Group reaction Simple sugars react with hydroxylamine to yield oximes. 10
- 11. d) Reducing reaction Glucose and Fructose very easily oxidizes. When glucose reacts with fehling of toluene solution it makes Red precipitate. 11
- 12. e) Hydrogen Cyanide Reaction When glucose reacts with hydrogen cyanide (HCN) it gives glucose cyanohydrin. 12
- 13. 2. Reaction with Alcoholic group a) Action of Metallic Hydroxides Metal Hydroxide reacts with glucose and fructose and form glucose and fructose metallic nutrients. Metallic nutrient such as Cu(OH)2, Ca(OH)2 ,Ba(OH)2 etc,. 13
- 14. b) Action of PCl5 When glucose reacts with PCl5 it forms Pentachloro fructose. 14
- 16. 4. Contains Asymetric carbon atom All monosaccharides contain one or more more asymmetric carbon atom accept the kitotriose and dihydroxyacetone. All compound having one or more asymmetrical carbon atoms shows optical activity and streoisomerism. 5. Streoisomerism- Compounds having same structure formula but different in spatial configuration are known as streoisomerism 6. D & L Isomers 16
- 18. PhysicalPropertiesofMonosaccharides 1. After dissolving in water all monosaccharides give a sweet taste. 2. All monosaccharides move across plasma membrane. 3. All monosaccharides are soluble in water. When they dissolve in water they would take up the ring form. This is the cause for their solubility in water. 4. When monosaccharides are dissolved in water they would initiate the lowering of water potential of the solution. 18
- 19. Structure&PropertiesofDisaccharides These are naturally found oligosaccharide. (Fructose + glucose) is found in sweet fruit and honey and some roots of plants. It is found in ripe grapes with composition 20 to 30% and therefore it is called also called grape sugar. Disaccharide are those carbon atom which are made by the two atoms of monosaccharides. Examples- Sucrose, Lactose, Maltose etc,. C6H12O6 + C6H12O6 C12H22011 +H2O Glucose Glucose Maltose C6H12O6 + C6H12O6 C12H22011 +H2O Glucose Fructose Sucrose Glucose + Galactose C12H22011 Lactose 19
- 20. Sucrose It is also called table sugar, sugar of Cane, sugar of beetroot etc,. Sucrose is mostly found in plants which takes photosynthesis and that is why it is one of the food which is found in crystal form. This is made by the juice of Cane or the roots of beetroot. It contains 50-20 % of sucrose. In India sugar is made by sugarcane and in Cuba, Ruse and Java it is made by beetroot. Its atomic formula is C12H22O11. It is colourless crystal material. 20
- 21. Maltose In simple words it is also called Malt sugar. It is developed by the decomposition of starch in plant. 21
- 22. Lactose (Milk Sugar) It is a sugar composed of galactose and glucose. lactose makes up around 2-8% of milk. The name come from latin word milk and “ose” used to name sugar. The component is white, water soluble, non-hygroscopic solid with a mildly sweet taste. It is used in the food industry. 22 Lactose
- 23. ChemicalProperties 1. Action of Heat 23
- 25. 4. Hydrolysis 5. Formation of Metallic Derivatives 25
- 26. 6. Action of Conc. Hydrochloric acid 26
- 27. Physical Propertiesof Disaccharides All disaccharides are soluble in water and give the sweet taste. All disaccharide cannot pass plasma membrane of the cell or there is no career enzyme that can carry disaccharides to move across the plasma membrane. When disaccharides are dissolve in water they would cause the lower of water potential of the solution. Among disaccharides maltose and lactose are reducing sugar while sucrose is non reducing sugar. 27
- 28. Polysaccharides Polysaccharides are high molecular weight carbohydrates which on hydrolysis yield mainly monosaccharide or product related to monosaccharides. A great majority of carbohydrates occur in nature as polysaccharide. Example- Starch, Glycogen, Cellulose etc,. 28
- 29. 1. Starch Occurrence- Starch occurs widely in plants especially in roots,tubers, seeds and fruits as a carbohydrates storage product and energy source. It is present in cerials, legumes, potatoes and other vegetables. It is found in colourless plastids in storage tissue and in stroma of chloroplast in plants. More than half of the carbohydrate is ingested by humans as starch. It is usually present inside the plant cell as insoluble granules which may be spherical, lens-shaped or ovoid. 29
- 30. Chemistry of Starch Natural stars consists of two components: Amylose (15-20%) a long unbranched straight chain component. Amylopectin (80-85%) a branch change polysaccharide Potato and serial starch are 20-30% of amylose and 70-80% of amylopectin. 30
- 32. Properties Starch is white soft amorphous powder and lacks sweetness. It is insoluble in water, alcohol and ether at ordinary temperature. Starch on partial hydrolysis by boiling with water under pressure at about 250°C break down into large fragments called Dextrin. Hydrolysis 32
- 33. 2. Glycolysis Occurrence- It is major reserve food in animals hence called animals starch) and also in many fungi and bacteria due to its been osmotically inactive. Glycogen is stored in liver and muscles of animal. It is especially abundant in liver where it may attain up to 7% of the wet weight. 33 Structure
- 34. Properties It is white amorphous, tasteless powder and is more soluble in water. It is non reducing sugar and gives red colour with iodine. The red colour however disappears on boiling and reappears on cooling. Hydrolysis On hydrolysis glycogen yield maltose. 34
- 35. 3. Cellulose Occurrence- Cellulose is not only the most abundant extracellular structural polysaccharide of plant world but is also the most abundant of all molecules in the biosphere. It is present in all land plants but is completely lacking the meat, egg, fish and milk. Cellulose occurs in the cell wall of plant where it contributes in a major way to the structure of the organism. The molecular weight of cellulose ranges between 20000 and 2,00,000 does corresponding 21250- 12500 glucose residues per molecule. 35 Structure
- 36. Properties It is fibrous tough white solid insoluble in water but soluble in ammoniacal cupric hydroxide solution. It gives no colour with Iodine. It lacks sweetness. Although insoluble in water, cellulose absorbs water and add to the bulk of the fecal matter. Hydrolysis Cellulose is relatively inert material and is completely degraded only under the most drastic condition. 36
- 37. Functions 1. They are most abundant dietary source of energy for all organism. 2. It is precursor for many organic compounds. 3. Carbohydrate participate in the structure of cell membrane and cellular function. 4. They are structural component of many organism. 5. Carbohydrate also serve as the storage form of energy. 37
- 38. Reference 1. Textbook of Biochemistry by U.Satyanarayana. 2. Fundamental of Biochemistry by J.L.Jain. 38