This document discusses carbohydrates, including their structure, functions, classification, and digestion. It defines carbohydrates as organic compounds found in foods and tissues that contain hydrogen and oxygen in a 2:1 ratio. Carbohydrates are classified as monosaccharides, disaccharides, oligosaccharides, or polysaccharides depending on their structure. Examples of monosaccharides include glucose, fructose, and galactose. Disaccharides are formed when two monosaccharides join together, such as sucrose, lactose, and maltose. Polysaccharides include starch and fiber, with starch being the main storage carbohydrate in plants. Carbohydrates provide energy and have various other functions in the body.

1. CARBOHYDRATE
Presentation by:
Prashanta Sharma Roy
Reg No: 2012131090
Dept. of Chemistry
SUST

2. CARBOHYDRATE
• A large group of organic compounds occurring in foods and
living tissues
• They contain hydrogen and oxygen in the same ratio as
water (2:1)
• Empirical formula: (CH2O)n

3. FUNCTION OF CARBOHYDRATE
• Provide us with energy
• Use protein in other beneficial ways
• Are necessary for fat oxidation
• Help Gastro-Intestinal (GI) function in the body
• Make our food more flavorful
• Help cellular recognition processes

4. CLASSIFICATION OF CARBOHYDRATES
Carbohydrates
Simple
Monosaccharides
Disaccharides
Complex
Oligosaccharides
Polysaccharides

5. MONOSACCHARIDES
• Carbohydrates that cannot be hydrolyzed to
simpler carbohydrates. i.e. glucose, fructose
etc.
Glucose:
• Carbohydrate form used by the body, referred to as
“blood sugar”
• Basic sub-unit of other larger carbohydrate molecules
• Cyclic forms of glucose formed when the hydroxyl group
on C-5 bonds to the aldehyde C-1.

6. MONOSACCHARIDES
Fructose:
• Sweetest of the sugars
• Occurs naturally in fruits & honey, “fruit sugar”
• Combines with glucose to form sucrose
Galactose:
 Combines with glucose to form lactose, “milk sugar”
 It is a monosaccharide sugar that is less sweet than
glucose and fructose.

7. DISACCHARIDES
Carbohydrates that can be hydrolyzed into two
monosaccharide. It is formed when two sugars are joined
together and a molecule of water is removed. eg. Sucrose
(which is hydrolyzed into glucose and fructose)
Sucrose:
 Known as table sugar
 Extracted from sugar cane or beet sugar
 On hydrolysis makes glucose and fructose

8. DISACCHARIDES
Lactose:
• Known as milk sugar
• Made of glucose and galactose
Maltose:
• Known as malt sugar
• Made of only glucose

9. JOINING AND CLEAVING SUGAR
MOLECULES

10. OLIGOSACCHARIDES
Short carbohydrate chains of 3 - 10 monosaccharides
Functions for cell recognition and cell binding
Found in legumes
Example:
Glycolipids
Stachyose

11. POLYSACCHARIDES
• Long carbohydrate chains of monosaccharides linked by glycosidic bonds
Types:
 Alpha bonds (found in starch)
 Beta bonds (found in fiber)
Starch:
Most common storage polysaccharide in plants
Composed of 10 – 30% amylose and 70-90% amylopectin depending on the source
Common sources are grains , potatoes, peas, beans, wheat

12. POLYSACCHARIDES
Fiber:
Found in food derived from plants
Includes polysaccharides such as cellulose, hemicellulose, pectin,
gums and mucilages
Also includes non-polysaccharides such as lignin, cutins and tannins
Fibers are not a source of energy because human digestive enzymes
cannot break down fibers
The bacteria in human GI tract can breakdown some fibers.

13. DIGESTION & ABSORPTION
Small Intestine:
Enzymes located on the cell membranes of the intestinal epithelial cells complete
digestion
Large Intestine:
Resistant starches and fibers may be digested by bacteria.
Produces short chain fatty acids.

14. THANK
YOU