Pharmacy- Pharmacognosy

1. Lipids & Fatty Acid
Copyright © 23/05/2013 by Omer
Bayazeid. All rights reserved.
Primary Metabolites

2. • Lipids are esters of long-chain fatty acids
and alcohols, or of closely related
derivatives.The chief difference between
these substances is the type of alcohol; in
fixed oils and fats, glycerol combines with
the fatty acids; in waxes, the alcohol has a
higher molecular weight.
• Lipids are hydrophobic or amphipathic small
molecules that may originate entirely or in
part by carbanion-based condensations of
thioesters (fatty acids, polyketides, etc.)
and/or by carbocation-based condensations
of isoprene units (prenols, sterols, etc.).

4. Are defined as those that on
hydrolysis yield at most two type of
primary product per mole,
e.g: Triacylglycerols
Simple Lipids:

5. O
ll
CH2−O−C
O
ll
CH2−O−C
O
ll
CH−O − C
glycerol
fatty acid
fatty acid
fatty acid
Triglyceride
The “tail” of a fatty acid is a long hydrocarbon chain, making it
hydrophobic. The “head” of the molecule is a carboxyl group
which is hydrophilic. Fatty acids are the main component of
soap, where their tails are soluble in oily dirt and their heads
are soluble in water to emulsify and wash away the oily dirt.
However,when the head end is attached to glycerol to form a
fat, that whole molecule is hydrophobic.

6. DefinitionDefinition:
• Fatty acids are aliphatic mono-carboxylic
acids that are mostly obtained from the
hydrolysis of natural fats and oils.
• Have the general formula R-(CH2)n-COOH
and mostly have straight chain (a few
exceptions have branched and heterocyclic
chains). In this formula "n" is mostly an
even number of carbon atoms (2-34) with a
few exceptions that have an odd number.
Fatty Acid

7. Fatty acids are classified according to
several bases as follows:

8. The terms saturated,
mono-unsaturated, and
poly-unsaturated refer to
the number of hydrogens
attached to the hydrocarbon
tails of the fatty acids as
compared to the number
of double bonds between
carbon atoms in the tail.
No double

9. They are lipids that contain additionalThey are lipids that contain additional
substances, e.g., sulfur, phosphorus, amino groupsubstances, e.g., sulfur, phosphorus, amino group
, carbohydrate, or proteins beside fatty acid and alcohol., carbohydrate, or proteins beside fatty acid and alcohol.
A) Glycolipids:They are lipids that containThey are lipids that contain
carbohydrate residues with sphingosine as thecarbohydrate residues with sphingosine as the
alcohol and a very long-chain fatty acid (24alcohol and a very long-chain fatty acid (24
Carbon series).Carbon series).
Compound Lipids:

10. GLYCEROL
F A T T Y A C I D
F A T T Y A C I D
e.g.,choline+
polar head long hydrophobic tail
B) Phospholipids: They contain Polar Phosphorus
Part and glycerol backbone
P

11. C) Lipoproteins: Lipoproteins are lipids
combined with proteins in the tissues.The lipid
component is phospholipid,cholesterol or
triglycerides. The holding bonds are secondary
Bonds.
Steroids are usually found in association with fat.Steroids are usually found in association with fat.
They can be separated from fats after saponificationThey can be separated from fats after saponification
since they occur in the unsaponifiable residue.since they occur in the unsaponifiable residue.
Steroids:Steroids:

12. Stearic acid CH3(CH2)16COOH
Systematic: octadecanoic acid
Shorthand: 18:0 (18C, no double bonds)
Structure and nomenclature of fatty acids
All fatty acids ionized at physiological pH; pKa <5
O
ll
C-O-
*
Long-chain carboxylic acids; building blocks of most
lipids

13. Linoleic acid
CH3(CH2)4CH=CHCH2CH=CH(CH2)7COOH
Systematic: cis, cis 9,12-octadecadienoic acid
Shorthand: 18:2ω6
This is shorthand for a fatty acid with 18 carbons and 2
double bonds. The ω6 indicates the double bond
closest to the methyl end is 6 carbons from the ω end.
Structure and nomenclature of fatty acids
If more than one double bond, the configuration is always
“methylene-interrupted” (-CH=CH-CH2-CH=CH-) with
cis double bonds. Always 3C between C=C bonds
So - the term 18:2ω6 completely defines the formula and
structure of linoleic acid

14. Fatty Acids: long-chain carboxylic acids
“kinks” – less packing
– more fluid
GOOD for
membranes
Virtually all natural C=C
double bonds are cis
C
C COOH3
HC
H
H
C
C COOH3
HC
H
H
C
C COOH
3
HC
H
H
C
C COOH
3
HC
H
H
cis-fatty acid
trans - fatty acid
COOH3
HC
COOH3
HC
saturated fatty acid

15. 1) In laurel as Lauric Acid.
2) In Nutmeg as Myritic Acid.
3) In Palm Tree as Palmitic Acid.
4) In Arachis as Arachidic Acid.
5) In Ligunm as Lignoceric Acid.
6) In Greek Oleum as Oleic Acid.
Some Natural Occurring Fatty Acids:

16. Aprocess in which esters in fats are
hydrolyzed with sodium or potassium
hydroxide ( NaOH or KOH ) to produce a
carboxylate anion which can act as a
surfactant.
Is the number of milligrams of KOH
required to neutralize the fatty acids
resulting from the complete hydrolysis of 1g
of fat.
Saponification
The saponification value

17. It is the number ofIt is the number of milligrams of KOHmilligrams of KOH
required to neutralize the free fatty acidsrequired to neutralize the free fatty acids
present inpresent in oneone gramgram of fat.of fat.
It is used for detection of hydrolytic rancidityIt is used for detection of hydrolytic rancidity
because it measures the amount of free fattybecause it measures the amount of free fatty
acids present.acids present.
Uses:Uses:
Definition:Definition:
Acids Number:Acids Number:

18. IODINE NUMBER
Iodine value is a measure of degree of unsatur-
ation, the number of carbon-carbon double
bonds in relation to the amount of fat or oil.
It is defined as the g iodine absorbed per 100g
of sample.

19. • Peroxide value measures the degree
of lipid oxidation in fats and oils but
not their stability.
• It is defined as the number of milli
equivalents of peroxide per kg fat.
• It is a measure of the formation of
peroxide or hydroxide groups that
are initial products of the lipid
oxidation.
PEROXIDE VALUE

20. Omega fatty acids fall into three groups,
identified as Omega-3, Omega-6, and
Omega-9. While omega-3 fatty acids are
best known, all three groups have
important benefits for overall health.
The omega-3 group includes ALA(Alpha
Linolenic Acid), EPA (eicosapentaenoic
acid) and DHA (docosahexaenoic acid).
Omega Fatty Acids and Essential Fatty Acids
(1) Omega-3:

21. While it’s generally understood
that omega-3 fatty acids are good
, the value of omega-6 and
omega-9 fatty acids is not always
as clear.
GLA (Gamma Linolenic Acid) is an
omega-6 fatty acid which your
body uses to produce hormone-like
substances (eicosanoids) that
support cardiovascular health. The
best-known natural sources are:
borage seed oil and evening
primrose oil.
(2) Omega-6 and 9 :

22. • Oleic Acid is a monounsaturated
omega-9 fatty acid that helps
support cholesterol levels that are
already within the normal range
and immune system function.

23. Essential Fatty Acids:
There are TWO essential fatty acids.Which means
you NEED to get them from the diet, because the
body cannot manufacture them.
(1) α-linolenic acid (LNA or ALA): an omega-3
fatty acid. absent in typical North American diet.
COH
O
1
91215
ALA
α-Linolenic acidΩ1 Ω3

24. (2)Linoleic acid (LA): an omega-6 fatty
acid found abundantly in soy oil, sunflower
seeds, pumpkin seeds,sesame seeds, corn oil,
and in most nuts.
Linoleic acid
cis-9,12-Octadecadienoic aicd, 18:2(∆
9,12
)
COH
O
1
912

25. Function of Essential Fatty Acids:
1. They are useful in the treatment of atherosclerosis
by help transporting blood cholesterol and lowering it
and transporting triglycerides.
2. The hormones are synthesized from them.
3. They enter in structure of all cellular and subcellular
membranes and the transporting plasma phospholipids.
4. They are essential for skin integrity, normal growth
and reproduction.
5. They have an important role in blood clotting (intrinsic
factor).
6. Important in preventing and treating fatty liver.
7. Important role in health of the retina and vision.
8. They can be oxidized for energy production.