1. Carbohydrates By
Dr. Ghulam Abbas

2. Carbohydrate functions
Energy sources (glucose/glycogen)
Structural element
cell wall (plants, bacteria)
connective tissues
adhesion between cells
AMORPHOUS GROUND SUBSTANCE
1. PROTEOGLYCANS (diagram)
a. Physical characteristics
1. polysaccharide and glycosaminoglycans (GAG)complexes 2. attached to an inner protein core 3. bottle brush arrangement 4. long polysaccharide chains 5. high carbohydrate content relative to protein 6. generally negatively charged
b. Major classes of proteoglycans
1. hyaluronic acid 2. chondroitin 3. dermatan sulfate 4. keratan sulfate 5. heparin sulfate
c. Functions
1. contributes to physical consistency of ground substance 2. an adhesive substance for collagen fibrils 3. transport and regulation of water and electrolytes 4. barrier to spread of bacteria 5. lubrication and viscosity (e.g.. synovial fluid) 6. absorb compressive loads

3. Plant cell wall The Gram positive cell wall
Muramic acid, in N-Acetylated form (MurNAc) is one of the building blocks of bacterial cell walls. It is similar to sialic acid in that it has a nine-carbon skeleton. MurNAc has a branched skeleton, however, where NeuNAc does not. Muramic acid can be visualized as the linkage of 2-deoxy-2-amino-D-glucose to D-lactic acid.
The Gram positive cell wall

4. Carbohydrates in Food
Chemical structures of carbohydrates contain many carbon atoms bonded to hydroxide group. They are also called sugars or saccharides. Carbohydrates can be small or very large molecules.
Sugars or saccharides: Scientists also use
The word saccharides to describe sugars. If
there is only one sugar molecule it is called
monosaccharide, if there are two, it is called
disaccharide. If there are three , it is a
trisachharadie.

5. Sugars Monosaccharides Disaccharides Glucose Fructose Galactose
Sucrose Table sugar (Glucose and Fructose)
Lactose Milk sugar (Glucose and Galactose)
Maltose Corn sugar (Glucose and Glucose)
Chemical formula of C6 H 12 and O 6
Glucose and Galactose are aldoses db O on first C; Glu OH 4 and 1; Gla 3 and 2
Fructose is a ketose

6. Monoosaccharide Aldose 6C: glucose, mannose 5C: ribose, xylose,
4C: erythrose, threose
3C: glyceraldehyde
Ketose 6C: fructose, sorbose

7. Monoosaccharide

8. Monoosaccharide
Galactose
Mannose
Ribose
Glucose

9. Sweetness of Sugars Sugar Sweetness Fructose 1.3 Sucrose 1.0
Glucose 0.56
Galactose
Maltose
Lactose

10. Carbohydrates
Carbohydrates act as the most important source of energy for our body and one of the main types of nutrients. In living systems carbohydrates mainly convert to glucose which is also called as blood sugar and uses this sugar as energy source.
The excess of glucose stores in the form of starch (in plants) and glycogen (in animal) for when it is needed. Depending on their chemical structures, carbohydrates can be simple or complex compounds.

11. Types of carbohydrates: There are two types of carbohydrates; Simple and complex carbohydrates. Most of our carbohydrates come from complex carbohydrates.
Simple carbohydrates: A sugar called glucose is the most important monosaccharide on Earth. In plants glucose is synthesized by photosynthesis and use in cellular respiration. Sugar is actually disaccharide. The sugar used in our dinner table is made of glucose and another monosaccharide called fructose.

12. Functional group isomers:
Monosaccharide like glucose, fructose, mannose and galactose can show different isomerism. For example, glucose and fructose are functional isomer of each other as glucose contains aldehyde group and fructose contains ketonic group in molecule.

13. Epimer Definition
They can also show stereoisomerism due to the presence of chiral carbon atoms. Those stereoisomers which are differing in its configuration at only one chiral carbon atom are called as Epimers. For example, glucose and galactose are Epimers of each other, as they differ in only in the position of hydroxyl group at C4.

14. Epimer Definition

15. Simple carbohydrates are composed of single unit sugars called monosaccharides and disaccharides.Glucose and fructose are examples of common monosaccharides.
Simple carbohydrates are easily digested and converted into sugars rapidly in blood stream.
Simple carbohydrates are also called sugars. They exist in either a natural or refined form. Natural sugars are found in fruits and vegetables.

16. What kinds of foods provide carbohydrates?
Some are in milk; most are in plant foods, including fruits, vegetables, grain products, dry beans, nuts, and seeds.

17. Oligosaccharide
Sugars which are formed by joining of 2-10 monomers units.
Examples: Maltose, sucrose, lactose, Reffinose.
Beans and other legumes contain a number of oligosaccharides (stachyose, raffinose) that are very poorly digested in the small intestine. These carbohydrates pass into the large bowel where they are fodder for bacterial fermentation.

19. Glycosidic linkage/acetal lingkage

20. Dietary Fiber: Plant materials that are eaten but can’t be digested by human enzymes.
Dietary Fiber in plants are cellulose, pectin and lignin. Although its rigid bonds are resistant to digestive enzymes [β(1-4 linked D-glucose)], and thus pass through our digestive system intact. Fiber is extremely important in maintaining good health.
Some of the benefits of fibers include:

21. Dietary Fiber
Regulation of blood sugar. Fibers slow down the digestion of other foods while it is eaten, and helps to prevent large changes in blood sugar.
Lowering the blood cholesterol: fiber binds with fatty acids and cholesterol into large clusters that our body can get rid easily.
Promotion of intestinal health: Fibers are helpful in digestion and prevent constipation and hemorrhoids by regulating bowel movement.
Adds to feeling of fullness when eating.

23. Dietary Fiber

24. How body uses carbohydrates
When we eat carbohydrates ,the body breaks them down into simple sugars, which are absorb into the blood stream. As the sugar level rises in body, the pancreases release a hormone called insulin. Insulin is needed to move sugar from blood into the cells, where sugar can be used as a source of energy.

25. Carbohydrates

26. Sugars
Glucose: The central actor in this game is glucose, known also as blood sugar, grape sugar and dextrose (D-glucose is dextrorotatory). Glucose is “reducing sugar” that is it is oxidized by ferric (Fe+3) and cupric (Cu+2) ions yielding reduced metal ions.
Galactose: It is found in milk and milk products. It is also a reducing sugar and form 6-membered ring when dissolved. Galactose is almost identical to glucose only exception being the position of “OH” group on carbon 4.

27. Sugars
Fructose: It is third (3rd) most common sugar found in our diet. As with glucose it also form ring structure when dissolved.
Because carbonyl group is on carbon 2, fructose form a “5 remembered ring” carbon 1 and 6 are attached to the central ring which effects both intestinal uptake and metabolism of carbohydrates.
Fructose is natural but limited component of our food, being found in limited amounts in many types of fruits and berries.
Fructose is one of the two sugars that are found in sucrose (table sugar). It is sweeter than table sugar.
It is thus suggested by many health experts that one can cut down on the calori intake by replacing sucrose with fructose. Since fructose is 30-40% sweeter than sucrose, one should be able to eat % less sugar and get the same sweetening effect.

28. Ribose
Ribose is essential part of our metabolic system, being found in physphorylated form in ATP and others things. The diet supplement industry has presented ribose as a strength and energy giving stuff.

29. Disaccharides
Sucrose: The disaccharide sucrose is composed of glucose and fructose joined by an alpha 1-2 bond. Sucrose is relatively “new comer” in our diet. It is actually not especially sweet, and we use large amount of it to get taste we desire in breakfast cereals, soft drinks, cakes and sweets.
C1,2 glycosidic bond

30. Lactose
Lactose (milk sugar) is a disaccharide composed of glucose and galactose.
The enzyme responsible for synthesis of lactose is specific for the beta form of glucose and the result is beta 1-4 glucosidic bond between the two monomers.
Lactose is the only substance with such bond which can be digested in human intestine.
This requires the presence of lactase, another enzyme involved in carbohydrate digestion that is produced and bound to the mucosal cell membrane.

31. Maltose
Maltose and isomaltose are not the major components of our diet but are formed from polysaccharides in the intestine through the action of amylase.
These disaccharides are glucose dimers and are digested by maltase and isomaltase that are produced and bound to the mucosal cell. The glucose formed is then readily absorbed.

32. Complex carbohydrates are often referred
as starch and starchy foods. They are found
in naturally in foods and also refined in
processed foods. Complex carbohydrates
as natural starches are found in;
Banana, barley, beans, brow rice,
chickpeas, lentils, nuts, oats, potatoes, root
vegetables, sweet corn, wholegrain cereals,
wholegrain pasta, yams.

33. Biscuits, Cakes and pastries. Chocolate Honey and Jams, Jellies
Refined sugars
Biscuits, Cakes and pastries.
Chocolate
Honey and Jams, Jellies
Brown and white cane sugar
Pizzas, prepared food and sauces
Soft drinks, sweets and snack bar.
Sugars; clockwise from top-left: White refined, unrefined, brown, unprocessed cane

34. Comples carbohydrates
Comples sugars (polysaccharides) are built from single-unit sugars joined in long chains. Two types of complex carbohydrates are particularly important in nutrition.
Starch: It is polysaccharide that plants use to store energy. It is the main constituent of comples carbohydrates in human diet.
Examples of starchy foods are potatoes, rice and pasta.

35. Starch
Amylose

36. Glycogen

38. Cellulose Monomer: glucose Bonding: -1,4 Carboxymethyl cellulose
The basic functions of CMC is to bind water or impart viscosity, stabilizethe other ingredients, orprevent syneresis
-control ice crystals in ice cream
-bulking agent because of high water binding
-at low pH it loses viscosity and had a tendency to precipitate
Cellulose
Monomer: glucose
Bonding: -1,4
Carboxymethyl cellulose

40. BONDING IN SUCROSE
C1,2 glycosidic bond

41. Polysaccharides
The minor difference results in entirely dissimilar 3-dimentional structure. Beta 1-4 linked glucosyl group from sheet that pack together to form the rigid structure called cellulose. This is the major polysaccharide of grass, leaves and trees and is said to include around 50% of all biological carbon found in our planet. The digestion of cellulose is entirely dependent upon intestinal flora in herbivores.
Starch in plant and glycogen in human has completely different structure.

42. C1,4 glycosidic bond
Starch
Cellulose

43. THE END