Lipids and its classification

examples of lipids
sources of lipids
definition
lipid classification
simple lipid
compound lipids
derived lipids
Miscellaneous lipids
biomedical importance

1. SIMS 305- Clinical Biochemistry Lipids Dr. Ali Raza Centre for Human Genetics and Molecular Medicine ( CHGMM), Sindh Institute of Medical Sciences (SIMS), SIUT.

2. Lipids Contents Examples of lipids Sources of lipids Definition Classification : Simple Lipids Compound Lipids Derived Lipids Miscellaneous Biomedical Importance

3. Examples of lipids Oil Fats Waxes Butter Mayonnaise Ghee Cream Cheese

4. Sources Plants Vegetable oil, Sunflower oil, Corn oil, Soybean oil Cotton seeds oil Pumpkin seeds Nuts and cereals Animals Eggs Fish

5. Lipids Heterogeneous group of organic substance Bloor criteria(1943 ) classified lipids based on their chemical composition Insoluble in water Soluble in Organic Solvents (Chloroform, Acetone) Relationship to the fatty acid as “Ester” Utilization by living organism

6. Lipids Ester of (fatty acids with) various alcohols Fatty acids: Hydrocarbon chain with a carboxylic acid at one end. Fatty acids Alcohol

7. Ester bond An ester forms when a hydroxyl reacts with a carboxylic acid, with loss of H 2 O.

8. Lipids Ester of fatty acids with various alcohols Fatty acids Alcohol

9. Lipids Classification I- Simple lipids: FA + Alcohols II- Compound lipids : FA + Alcohols + X (Phosphoric Acid) III- Derived lipids: On hydrolysis yields i ) FA ii) Alcohols iii) Glycerides IV- Miscellaneous

10. I- Simple lipids “ Ester of fatty acids with various alcohols” a- Neutral Fats b- Waxes

11. Neutral Fats Triesters of fatty acids with glycerol E.g . Triglycerol TGs

12. I- Simple lipids b- Waxes: “ Ester of fatty acids with higher monohydroxy aliphatic alcohols”

13. b- Waxes True waxes: Esters of higher fatty acids with higher straight chains alcohols Examples:   Beeswax  Carnauba  wax

14. b- Waxes ii) Cholesterol Esters: ( Cholesteryl ester) Esters of higher fatty acids with cholesterol

15. b- Waxes ii) Vitamin A and D Esters: Esters of higher fatty acids with vitamin A and D

16. II- Compound lipids Esters of fatty acids containing other groups or in addition to an alcohol and fatty acids. FA + Alcohols + X (Phosphoric Acid)

17. II- Examples of Compound lipids : Phospholipids: lipids contain Phosphoric acid, nitrogenous base & other substituents Glycolipids: lipids contains carbohydrates Sulfolipids : lipids possess Sulphate groups Aminolipids : Proteolipids Lipoprotein: lipid attach to protein

18. Phospholipids contains Phosphoric acid, nitrogenous base and other substituent in addition to fatty acid and glycerol .

19. Examples of Phospholipids Phosphatidyl choline (Lecithin) Phosphatidyl ethanolamine ( Cephalin ) Phosphatidyl inositols ( Lipositols ) Phosphatidyl serine Plasmalogens Sphingomelins

20. Structure of Phospholipids

21. Glycolipids lipids contains carbohydrates Contains alcohol ( S phingosine or S phinogol ) and nitrogenous base in addition to fatty acid Phosphoric acid and glycerol are absent

22. Glycolipids   Two types of Glycolipids Cerebrosides Gangliosides

23. III-Derived lipids Derivative obtained on hydrolysis of simple and compound lipids and exhibit lipid characteristics Fatty acids (FA) Glycerides ( monoacylglycerol or diglycerides , glycerol ) Alcohol: High molecular weight , straight chain of alcohol yield on wax hydrolysis E.g. Glycerol , cholesterol

24. IV- Miscellaneous Aliphatic hydrocarbons such as iso-octadecane , E.g ; found in liver fat Hydrocarbon found in bee wax and animal waxes Carotenoids Vitamin E Vitamin K

25. Importance of Lipids Energy source or fuel: 9.5 C/ gram Phospholipids and Lipoprotein constituents of Cell walls and cell organelles Lipoprotein are carrier of triglycerides, cholesterol, Phospholipids Insulating effect in the body lipids are necessary for Fat soluble vitamins (A , D, E and K )

26. 26 Reference: Textbook Medical Biochemistry by Chatterjea , S ixth Edition, Chapter 4 https://www.amazon.com/Textbook-Medical-Biochemistry-M-D-Chatterjea/dp/9350254840