1. Unit III: Biochemistry A. Biological Macromolecules B. Metabolism

2. Biological Macromolecules
Lipids
Carbohydrates
Proteins
(4. Nucleic Acids – not covered in this class)

3. What will we learn about each Macromolecule….
Structure and Function
Metabolic Importance
Nutrition and Medical Implications

4. Ch 15 Lipids

5. What are lipids?
Group of molecules not defined by structure but by common characteristics
non-polar, soluble in non-polar solvents like methylene chloride, gasoline, ether
Not soluble in
A polar solvent like water….

6. Types of Lipids
1. Fatty Acids 2. Fats and Oils 3. Waxes (structural recognition only) 4. Steroids 5. Phospholipids 6. Fat soluble Vitamins (know basics)

7. Lipids and Health BMI: Body Mass Index: Height vs weight
Simple measure to label patients in rubrics ranging from underweight (anorexia/malnutrition…) to overweight (obese)
how to measure BMI
Blood Lipids: blood lipid panel measures cholesterol, LDL, HDL, triglycerides (heart attack risk?)

8. Blood Lipids
Blood Lipids
Blood Lipid Panels from Blood Tests

9. CAD- Coronary Artery Disease
Lipid deposits clogging arteries in the body and heart
CAD intro
Risk Factors for CAD
Hypertension, Diabetes, elevated cholesterol
smoking
sedentary lifestyle
stress
obesity
male sex
family history
older age
Type A personality

10. Monomer/Polymer of Triglycerides
Monomer: Fatty acid, glycerol (phosphate)
Macromolecule: Triglyceride (fats/oils), Phospholipids
No true polymers….other lipid classes do not have a typical monomer/polymer relationship!!!

11. 1. Fatty Acids Long chain hydrocarbons with a carboxylic acid on C#1
Opposite end is called the Omega end
Know prefixes from 11 – 20
IUPAC: 12 – dodec: Dodecanoic Acid

13. Fatty Acids are…. Aliphatic molecules:
hydrophobic (hydrocarbon) as well as hydrophilic (carboxyl)
hydro-
philic
hydrophobic
Hydrocarbon is longer/stronger makes molecule overall hydrophobic

14. Common names of 4 saturated Fatty Acids
C12 – Dodecanoic Acid: Lauric Acid
C14 – Tetradecanoic Acid: Myristic Acid
C16 – Hexadecanoic Acid: Palmitic Acid
C18 – Octadecanoic Acid: Stearic Acid
Mnemonic: Lipids Make People Survive!

15. Lipids Make People Survive
Fatty Acids to know…
Lauric Acid (C12)
Myristic Acid (C14)
Palmitic Acid (C16)
Stearic Acid (C18)
Lipids Make People Survive

16. Types of Fatty Acid Saturated FA: only single bonds between Carbons
Unsaturated FA: have some double bonds between Carbons
a. trans double bonds

17. Unsaturated FA b: cis-double bonds
Polyunsaturated FA: omega fatty acids alternating 2 single with 1 cis-double bds forms ‘omega’ like loops
Carboxyl omega end

18. Shapes of Unsaturated Fatty Acids

19. Physical Properties of Fatty Acids
Saturated/Trans fatty Acids
highest melting point (Ex: Stearic Acid: 69oC)
Perfect alignment: high Van de Waals intermolecular attractions
Trans fatty acids do not naturally exist, man made product
Are the most stable fatty acids

20. Physical Properties of Fatty Acids
Unsaturated fatty acids
lower MP due to kinks: low Van de Waals (example Oleic Acid: MP 13oC)
Less stable: double bonds can break! Fatty acid goes rancid…
In nature all unsaturated FA have cis-bonds
Cis-double bonds start either at omega-3 or omega 6 carbon

21. Physiologically Important Fatty Acid Metabolites
1. Omega 6 and 3 FA, are essential fatty acid: limited production in body, need to be absorbed from food
2. Arachidonic Acid AA
C 20:4 Omega-6 FA
Precursor for Prostaglandins PG

22. Prostaglandins - PG
Hormone-like lipids with regulatory functions: PG1: heart rhythm, blood clotting, stomach lining
PG2: inflammation

24. Why do we care?

25. Videos
NSAID effect and side effect
stomach side effect

26. Warm -up Draw in Kekule a Tridecanoic Acid Lauric Acid
Octadecanoic Acid
1. Which one has the highest boiling pt?
2. Which one is also called stearic acid?

27. IUPAC of unsaturated Fatty AcidsΩ
C# C#18
α-C (first next to carboxyl)
C 18 : 4n -3
C: 18 means its a Fatty Acid with 18 carbons
4n means it has 4 double bonds
-3 means first double bond at Ω Carbons #3
Always draw FA from the omega end!!!

28. Draw
C18:1n-6
C18:1n-6 trans
C16:4n-3

29. Warm-up: Draw An ester between Decanol and Stearic acid
What lipid class does the resulting molecule belong to?