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INDUCTION
Enumerate Food
Nutrients
Ghee
Butter
Cheese
Curds
Butter
Milk
Milk
Chicken
Fish
Cheese
Food Nutrients
Body Constituents
Carbohydrates
Proteins
Lipids
LIPIDS
CHEMISTRY AND FUNCTIONS
SYNOPSIS/CONTENTS
WHAT ARE LIPIDS?
DEFINITION OF LIPIDS
CLASSIFICATION OF LIPIDS
BIOMEDICALLY IMPORTANT LIPIDS
STRUCTURE,FUNCTIONS,PROPERTIES
AND RELATED DISORDERS OF LIPIDS.
INTRODUCTION
WHAT ARE LIPIDS?
Lipids are :
Organic Biomolecules
Occurs in Plants and Animals
Hydrophobic
Heterogeneous
Esters
Food Nutrient
Secondary Source of Energy
Structural Components
Heterogeneous Nature Of Lipids
Features Of Lipids
L
Heterogeneous
I
P
Structure
I
D
Functions
S
Lipids are biomolecules
relatively :
Smaller in size
Less dense
Unlike Carbohydrates and
Proteins Lipid structures
are not Bio-Polymers.
(Lipid structure contains no repeatedly
linked Monomeric units)
Solubility Of Lipids
Solubility Of Lipids
Lipids are relatively Insoluble in
Water/Polar Solvent Water/polar
solvents
Since they are Non polar and Hydrophobic
Solubility of Lipids
Lipids are readily soluble in
non polar Organic solvents /Fat
Solvents
Acetone
Alcohol (Hot)
Benzene
Chloroform
Ether
Chemical Nature Of Lipids
Chemically Lipids are Esters :
Lipids are Esters of Fatty acids
with Alcohol and attached with
other groups.
Lipids are relatively or potentially
associated with Fatty acids.
DEFINITION OF LIPIDS
Lipids Bloor's Definition
Lipids are Organic, Heterogeneous
Hydrophobic Biomolecules
Relatively insoluble in water and
soluble in organic solvents.
Chemically Esters of Fatty acids
with Alcohol.
Utilized by body to produce ATP
Classification Of Lipids
With Examples of
Biomedical y Important
Lipids
Lipids are Classified
Into
Three Main Classes
Three Main Classes of Lipids are:
i.
Simple Lipids
ii. Compound /Complex Lipids
iii. Derived Lipids
1. Simple Lipids/Neutral Lipids
Chemically Simple Lipids are:
Esters of Fatty acids with
an Alcohol
Sub Classes Of Simple Lipids
Depending upon the type of Alcohol :
Simple Lipids are of two sub types:
Fats/Oils
(Alcohol is Glycerol)
Waxes
(Alcohol- Cholesterol/ Retinol)
Fats/Oils/TAG
Chemical name of Fat /Oil
Triacylglycerol
Fats/Oils/TAG:
Chemically Esters of Fatty acids
with Glycerol(Trihydric Alcohol)
Three Fatty acids linked to a
Glycerol molecule.
Waxes :
Waxes are Simple Lipids
Waxes are chemically Esters of
Fatty acids with higher
complex, monohydric
,Alcohols, other than Glycerol.
Examples Of Human Body Waxes :
Cholesterol Ester
(Cholesterol Palmitate)
Retinol Ester
(Retinol Palmitate)
Compound/Complex Lipids
Compound Lipids is a class
of Lipids
Chemically composed of
Fatty acids Alcohol and
an Additional group.
Depending upon the
Type of Additional group
Types of Compound Lipids are:
Four Names Of Compound Lipids
1. Phospholipids
2. Glycolipids
3. Lipoproteins
4. Sulfolipids
Phospholipids
Glycerophospholipds
Sphingophospholipids
Glycosphingolipids
Cerebrosides
Gangliosides
Globosides
Sulfatides
Lipoproteins
Chylomicrons
VLDL
LDL
HDL
Derived Lipids
Derived Lipids are Hydrolytic
products of Simple or
Compound Lipids and their
derivatives.
Examples of Derived Lipids:
Fatty Acids
Alcohols:
Glycerol
Sphingol
Cholesterol
Other Examples Of Derived Lipids
Lipid like compounds Derived from
Fatty acids and Sterols:
Steroidal Hormones: Derived from
Cholesterol
Fat Soluble Vitamins (A,D,E and K)
Eicosanoids (Prostaglandins ,
Leukotrienes ,Thromboxanes)
Ketone Bodies (Partial Oxidized Products
of Fatty acids)
Bloor's Classification Of Lipids
Four Classes of Lipids By Bloor
A. Simple Lipids
B. Complex/Compound
Lipids
C. Derived Lipids
D. Miscellaneous Lipids
A. Simple Lipid
Simple Lipids are Ester of fatty acids with various
alcohols
Fats and Oils
Triglycerides
Waxes
Cetyl alcohol esters of fatty acids(Bees wax)
Cholesterol Esters
Vitamin A Esters
Vitamin D Esters
B. Compound lipid
B. Compound Lipids are Esters of fatty acids with
alcohol with an additional groups
Phospholipids : contains phosphoric acid and
often a nitrogenous base
Glycolipids:
contains aminoalcohol
Spingosine, carbohydrate, N-base;
Lipoproteins : Lipids attached to plasma/other
proteins
Sulfolipids : contains sulfate group
Lipopolysaccharides: lipids attached to
polysaccharides
C.Derived Lipids ?
Hydrolytic products of Simple &
Compound Lipid
? Diacylglycerol
? Monoacylglycerol
? Fatty acids
? Alcohols : Cholesterol
D.Miscellaneous Lipids
Substances with Lipid characters
Carotenoids: b-Carotenoid
Squalene :
Vitamin E and K
Eicosanoids
Classification of Lipids
Simple and complex lipids
Simple
Complex
Glycerophospholipids
Glycolipids
Phosphoglycerides Sphingolipids
FA
FA
FA
GLUCOSE
ne
ne
GALACTOSE
e
rol
e
rol
yc
FA
yc
FA
ngosi
ngosi
Gl
Gl
FA
Sphi
PO 3-
3-
Sphi
4
ALCOHOL
PO4
CHOLINE
FA
Human body Lipids
Types of Lipids
Depending On
Saponification Property
Lipid Classification
Lipids
Nonsaponifiable
Saponifiable
s
id
Steroids
Prostaglandins
n
s
o
f
L
ip
Simple
c
tio
Complex
a
l
F
un
Sphingolipids
l
o
g
ic
Phosphoglycerides
1
7
.
1
Bio
Waxes
Triglycerides
Types of Lipids
Depending Upon Polarity
Neutral Lipids: (Non Polar Lipids)
Triacylglycerol
Cholesterol Ester (Cholesterol
Palmitate)
Amphipathic/Amphiphillic Lipids:
(Contain Polar and Non polar Groups)
Phospholipids
Cholesterol
Types of Lipids
Depending Upon Functions
Types Of Lipids
Based On Alcohol
Types Of Lipids
Based Upon the
Main Components
Names Of Important
Body Lipids
Biomedical y Important Lipids
1. Fatty Acids (FAs)
2. Triacylglycerol (TAG)
3. Phospholipids (PL)
4. Lipoproteins (LP)
5. Glycolipids
6. Cholesterol (Free)
7. Cholesterol-Ester (Esterified)
Biological Functions
Of Lipids
Lipids have
dietary and
Calorific value
Lipids are chief
constituents of human
food.
Dietary Lipids Ingested
(eaten) are digested,
absorbed and assimilated
in human body.
Lipids are highly reduced
substances with CH2 bonds.
Oxidation of the CH2 bonds of
Fatty acids, generate chemical
form of energy ATP.
Thus Lipids serve as a
secondary source of
energy (ATPs) to human
body.
Lipids are Reservoir of Energy
In a Well Fed Condition
Lipid Triacyl Glycerol (TAG) subcutaneously is
stored in Adiposecytes
In unlimited amount and in anhydrous
concentrated form.
It provide high potential source of energy for
cellular use.
Lipids
Superior Than
Carbohydrates
Lipids are Superior Than Carbohydrates
Lipids have Higher Calorific value
(9Kcal/gm)
High storage content , can be
stored in unlimited amount.
They provide energy source for
longer duration.
(During Marathon Races)
Thus Lipids serve as
major reservoir of
energy for long term
use in human beings.
Other Importance Aspect Of
Dietary Lipids
Fatty Foods are associated with
Fat soluble Vitamins
(Vit A,D,E and K)
?Dietary Lipids (TAG and PL) are
sources of essential Fatty acids to
human body.
Structural Role Of Lipids
Lipids are fundamental
structural components
of biomembranes
Biomembranes Lipids
1. Phospholipid bilayer
2. Glycosphingolipids
3. Cholesterol
Study Of Various Classes Of Lipids
Study Of Derived Lipids
Study Of Fatty Acids
FATTY ACIDS( FAs)
Derived Lipids
BASIC COMPONENT
OF LIPIDS
Fatty Acids (FA)
Fatty Acids (FA) are
relatively or potentially
related to various Lipid
structures.
Fatty Acids (FA)
Fatty acids are responsible to
form different forms of Lipids:
Simple Lipids
Compound Lipids
Miscellaneous Lipids
Fatty Acids Are Derived Lipids
Fatty acids are classified
under Derived Lipids:
Since Fatty acids are
Hydrolytic products of
Simple and Compound
Lipids.
Definition of Fatty acids
Fatty acids are chemically Organic
acids
With Aliphatic Hydrocarbon chain
(of varying length C2 to C24) with
Mono terminal Carboxylic acids.
Structure Of Fatty
Acids
Different Forms Of
Fatty acids In Body
Free Fatty acid /Unesterified Fatty acid
Fatty acid has free
Carboxylic group
Fatty acid not linked to an
Alcohol by an Ester bond.
Esterified Fatty acid/Bound form of Fatty Acid
Fatty has no free
Carboxylic group
Fatty acid is linked to
an Alcohol with an Ester
bond.
In living beings Fatty acids are not
generally present in free form.
Fatty acids are naturally and mostly present
in bound form in the plant and animals.
Fatty acids are linked to Hydroxyl group
of an Organic Alcohol by an Ester linkage.
Thus Fatty acids are mostly
present as Esterified form in
natural living beings.
(Plant, Animal and Human Bodies)
Classification of Fatty acids
With Different Modes:
Classification of FAs Based on:
1. Total number of Carbon atoms in a
Fatty acid structure.
2. Hydrocarbon chain length of Fatty
acid
3. Bonds present in Fatty acid
4. Nutritional requirement of Fatty acid
5. Chemical nature and structure of
Fatty acids
6. Geometric Isomerism of UFAs
Fatty acids Based on
Total Number of Carbon atoms
Even numbered Carbon
Atom Fatty acids
Odd numbered Carbon
Atom Fatty acids
Most naturally occurring
Fatty acids are even carbon
numbered FAs.
Since biosynthesis of Fatty
acids uses 2 Carbon units
Acetyl-CoA(C2).
Examples of Even Carbon
Numbered Fatty acids:
Butyric Acid (C4)
Palmitic Acid (C16) (Most Common)
Stearic Acid (C18)
Arachidic acid (C20)
Odd Carbon numbered Fatty acids
are less related to human body
Examples of Odd carbon Fatty acid
Propionic Acid ( 3C)
Valeric acid (5C)
Types Of Fatty acids Based on
Hydrocarbon chain length
Short Chain Fatty acids (2-6 Carbon
length)
Examples:
Acetic acid (C2)
Propionic acid (C3)
Butyric acid (C4)
Valeric acid (C5)
Caproic acid (C6)
Medium Chain Fatty acids (8-14 Carbon length)
Examples:
Caprylic acid (C8)
Capric acid (C10)
Lauric acid (C12)
Myristic acid (C14)
Long Chain Fatty acids ( 16-20 Carbon length)
Examples:
Palmitic acid (C16)
Palmitoleic acid (C16)
Stearic acid (C18 )
Arichidic acid (C20)
Arachidonic acid /ETA(C20)
Timnodonic acid/EPA (C20)
Very Long Chain Fatty Acids (C22 onwards )
Examples:
Behenic acid/Docosanoic (C22)
Cervonic acid/DocosaHexaEnoic (C22)
Clupanodonic (C22)
Erucic acid/Docosa 13 Enoic (C22)
Lignoceric acid (C24)
Nervonic /Tetracosaenoic (C24)
Cerotic acid/Hexacosanoic (C26)
Fatty acids Based on the number of
Bonds present
Saturated Fatty acids(SFAs)
Fatty acids having single bonds in
hydrocarbon chain structure.
Examples:
Acetic acid (C2)
Butyric acid (C4)
Palmitic acid (C16)
Stearic acid (C18)
Arachidic acid(C20)
Unsaturated Fatty acids(UFAs)
Fatty acids having double bonds in its
structure.
Types of UFAs:
Monounsaturated Fatty acids (MUFAs)
Polyunsaturated Fatty acids (PUFAs)
Monounsaturated Fatty Acids(MUFAs):
MUFAs have one double bond in a fatty
acid structure
Examples:
Palmitoleic acid (C16:1;9) (7)
Oleic acid (C18:1;9)(9)
Poly Unsaturated Fatty Acids (PUFAs):
UFAs with two or more double bonds in
the structure are termed as PUFAs.
Examples:
Linoleic(18:2;9,12) (6)
Linolenic(18:3;9,12,15) (3)
Arachidonic(20:4;5,8,11,14) (6)
Timnodonic (20:5;5,8,11,14,17) (3)
Cervonic/Docosa Hexaenoic acid(DHA)
(22:6;4,7,10,13,16,19) (3)
Remember
Double bonds are weaker
/unstable bonds.
They get easily
cleavable/metabolized
More the degree of
Unsaturation in Fatty acids.
More is the unstability of
Fatty acids.
Fatty acids Based on the
Nutritional Requirement
Nutritionally Essential
Fatty acids
Nutritionally Essential Fatty
acids:
The Fatty acids which are not
biosynthesized in the body and
are taken through nutrition/diet
essentially.
PUFAS are nutritionally essential
Fatty acids.
Examples of Essential Fatty
Acids/PUFAs:
Linoleic
Linolenic
Arachidonic acids
Timnodonic and
Cervonic
Human body have no Enzyme
system to introduce double bond
beyond Carbon atom 10 in the
hydrocarbon chain.
Hence PUFAs not biosynthesized
in human beings.
Nutritional y Non essential
Fatty acids
Nutritionally Non essential Fatty
acids:
Fatty acids which are
biosynthesized in the body and
are nutritionally non essential Fatty
acids.
Saturated Fatty acids and MUFAs
are non essential Fatty acids.
Examples Of Non Essential
Fatty Acids
Palmitic
Stearic
Oleic acid
Fatty acids Based on
Chemical nature and Structure
Aliphatic Fatty acids:
Straight Hydrocarbon chain
Examples:
Palmitic acid (C16)
Stearic acid (C18)
Branched Chain Fatty acids:
Possess Branched chains
Examples:
Isovaleric (C5)
Phytanic acid (Butter , dairy products)
Cyclic Fatty acids :
Contains Ring structure
Examples:
Chaulmoogric acid
(Used for Leprosy treatment in olden days)
Hydnocarpic acid
Hydroxy Fatty acids:
Contain Hydroxyl Groups
Examples:
Cerebronic acid (C24)/
2-HydroxyTetracosanoic acid
Ricinoleic acid(C18) (Castor oil)
Based on Geometric Isomerism
of Unsaturated Fatty acids
Cis Fatty Acids:
The Groups around double bond of
Unsaturated FAs are on same side.
Examples:
Cis Oleic acid (rich in Olive oil)
Palmitoleic acid
Trans Fatty Acids :
The groups around double bond of
UFAs are on opposite side
Example :
Elaidic acid /Trans Oleic acid
(Hydrogenated Fats )
Structures Of Fatty Acids
The Hydrocarbon chain of each
Fatty acid is of varying chain
length (C2 - C24).
Fatty acid structure have two
ends:
Carboxylic group(-COOH) at
one end (Delta end denoted as
)
Methyl group (-CH3) at another
end (Omega end denoted as )
Saturated Fatty acids
structures are Straight.
Unsaturated Fatty acids
structures are bent(Kink).
More the degree of
unsaturation in FA/More
double bonds in FA
structure
More is the bent of Fatty
acid structure.
Saturated FAs: with straight
structures are tightly
packed together.
Unsaturated FAs: with bent
structures are not compact
and has no tight packing.
Fatty acid Composition
of Human Body
Fatty acid
Percentage
Oleic acid
50% (MUFA)
Palmitic acid
35% (SFA)
Lionleic acid
10% (PUFA)
Stearic acid
5% (SFA)
Thus the most abundant
Fatty acids present in
human Lipids are:
Oleic acid (50%)
Palmitic acid(35%)
Most abundant Fatty acid in a
healthy human body is Oleic acid
(Rich in MUFA).
Oleic acid is richly associated with
Olive oil.
Hence eating Olive oil is
advisable for proper body
development and good health.
Nomenclature Of
Fatty acids
Naming And Numbering
Of Fatty Acids
Every Fatty acids has a:
Common Name
Systematic Name
Most of the Fatty acids are
known by their common
names.(since easy to use)
Systematic names of Fatty
acids are limited in use.
(Since not easy to use)
Long chain Fatty
acids are termed as
Acyl chains.
vThe systematic names of
Saturated Fatty acids are
named by adding suffix `anoic'.
v Example : Hexadecanoic
acid(Palmitic acid- C16)
The systematic names of
Unsaturated Fatty acids are
named by suffix `enoic'.
Example: Octadecaenoic
acid(Oleic acid- C18)
S.N Common
Systematic Name
Name
1
Palmitic Acid Hexadecanoic Acid
2
Stearic Acid
Octadecanoic Acid
3
Oleic acid
Octadecaenoic acid
4
Linoleic Acid
Octadecadienoic acid
5
Linolenic Acid Octadecatrienoic acid
6
Arachidonic
Eicosatetraenoic acid
acid
Numbering Of Fatty Acids
Numbering of Fatty acids is done
from :
Both the ends of Fatty acids and
From Carboxyl Group end() :
the Carboxylic acid group of
Fatty acid is C1, C2 is next
adjacent ,C3 and so onn.
The name of Carbon atom
next to the functional group
?COOH of a Fatty acid is ,
next Carbon is , , ,
and so onn.
Carbon atoms from
Methyl(?CH3) group at
non polar end() of a
fatty acid are numbered
as 1,2,3 and so onn.
Fatty Acid Nomenclature
FA Nomenclature is Based On
Chain length
Number of Carbon atoms in FA
Number and Position of Double
bonds
Position of double bond from
Methyl/Omega or Carboxyl/Delta end
Short Hand Representations
of Fatty acids
Short Hand Representations
of Fatty acids:
Palmitic Acid (16:0)
Palmitoleic acid (16:1;9)
First digit stands for total number of
carbon atoms in the fatty acid.
Second digit designates number of
double bonds.
Third digit onwards indicates the
position of double bonds.
Fatty-acid Nomenclature
Named according to chain length
C18
Fatty-acid Nomenclature
Named according to the number of
double bonds
C18:0
Common name:
Stearic acid
Fatty-acid Nomenclature
Named according to the number of
double bonds
C18:1
Common name:
Oleic acid
Fatty-acid Nomenclature
Named according to the number of
double bonds
C18:2
Common name:
Linoleic acid
Fatty-acid Nomenclature
Named according to the number of
double bonds
C18:3
Common name:
Linolenic acid
Omega System Nomenclature
Named according to the
location of the first double bond from the
non-carboxyl Methyl end (count from the
Methyl end /Omega end )
Omega Fatty-acid Nomenclature
Omega 9 or n?9 fatty acid
Omega 6 or n?6 fatty acid
Omega 3 or n?3 fatty acid
Stearic acid (18:0)
Oleic acid (18:1;9)
Linoleic acid (18:2;9,12)
Linolenic acid (18:3;9,12,15)
Arachidonic acid
(20:4;5,8,11,14)
A Fatty acid may also be designated
as :
Linoleic acid (18C;9,12)
Linolenic acid (18C;9,12,15)
indicates from COOH end.
9,12,15 are double bond
positions from delta end.
Short Hand Presentation of FA
14:0 Myristic acid
16:0 Palmitic acid
18:0 Stearic acid
18:1 cis D9 Oleic acid (9)
18:2 cisD9,12 Linoleic acid(6)
18:3 cisD9,12,15 a-Linolenic acid (3)
20:4 cisD5,8,11,14 Arachidonic acid(6)
20:5 cisD5,8,11,14,17 Eicosapentaenoic acid(3 )
Omega Series Fatty Acids
Omega Fatty Acids
Omega Fatty acids are Unsaturated
Fatty acids (UFAs)
In whom the position of double
bond is counted from Omega
end/Methyl end as() carbon atom
Terminal Methyl group is 1
Classification/Types
Of
Omega Fatty Acids
Types Of Omega Fatty acids
3 Fatty acids
6 Fatty acids
7 Fatty acids
9 Fatty acids
Omega Classification of
Fatty acids is used frequently
in
Nutrition and Clinical
practice.
Omega 3 Fatty Acids
Omega 3 Fatty Acids
Fatty acids having their
first double bond at
3 carbon atom are
Omega 3 Fatty acids.
Examples of 3 Fatty acids
Linolenic (18:3;9,12,15) (3)
Timnodonic/EPA
(20:5;5,8,11,14,17)(3)
Clupanodonic acid/(Docosa
Pentaenoic Acid): (DPA)
(C22:5;7,10,13,16,19 )(3)
Cervonic/Docosa Hexaenoic Acid
(DHA)(22:6;4,7,10,13,16,19)(3)
Omega 3 Fatty acids are
PUFAs
Not biosynthesized in
human body.
Nutritionally essential Fatty
acids.
They have to be taken
essentially through diet .
Dietary Sources Of
Omega 3 Fatty Acids
Omega 3 Fatty acids are richly
present in:
Green leaves
Algae
Fishes
Animal Meat
Natural Plant Oils
Dietary rich sources of
Omega-3 Fatty acids
Are Fish and Fish oils:
Docosahexaenoic acid
(DHA)/Cervonic acid
Eicosapentaenoic acid
(EPA)/Timnodonic acid
Functions Of Omega 3 FAs
Omega 3 Fatty acids are components
of cell biomembranes.
Omega 3 Fatty acids are more
associated to Human brain.
Helpful in growth ,development
and functioning of brain.
Thus Omega 3 fatty
acids plays good role in
Developing mental
well being of infants
and adults.
Since Omega 3 Fatty Acids
are PUFAS
They are easily
metabolizable in human
body
Omega 3 Fatty acids Reduces risk of
heart disease:
By stimulating Prostaglandins
and Prostacyclin's that reduces
Platelet aggregation.
Which reduces blood clotting
and Thrombus formation.
Omega 3 Fatty acids have
pleiotropic effects(more than on
effect):
Cardio protective effect
Lowers Blood pressure
Anti-Inflammatory
Anti-Atherogenic
Anti-Thrombotic
Thus Fish Eaters has good
Brain development with
an efficient nervous
function.
Protected from Heart
attacks.
Deficiency Of Omega 3 Fatty acids
Deficit of omega 3 fatty acids affect
the normal growth ,development
and functioning of brain.
Persons may suffer from mental
illness like:
Depression
Attention deficit
Dementia
Deficiency of Omega 3 Fatty
acids :
Alters the cell membrane
structure.
Increases the risk of heart
attack.
Omega 6 Fatty Acids
Omega 6 Fatty Acids: These fatty
acids has their first double bond at
6 carbon atom.
Examples of 6 Fatty acids:
Linoleic acid(18:2;9,12) (6)
Arachidonic acid(20:4;5,8,11,14) (6)
Omega 7 Fatty Acids
Omega 7 Fatty Acids fatty acids
has their first double bond at 7
carbon atom.
Palmitoleic acid (C16:1;9) (7)
Omega 9 Fatty Acids
Omega 9 Fatty Acids: These fatty
acids has their first double bond at
9 carbon atom.
Examples of 9 fatty acids:
Oleic acid (C18:1;9)(9)
Nervonic acid (C24:1;9)(9)
Poly Unsaturated Fatty Acids
(PUFAs)
Dietary Rich Sources Of
PUFAs
PUFAs are nutritionally
essential since they are not
biosynthesized by human beings
Hence Human beings should take
dietary Lipids to get essential
Fatty acids.
Rich sources of dietary
essential PUFAs are:
Vegetable Oils
Fish and Fish oils
Green Leaves, Algae
Arachidonic acid(PUFA)
can be synthesized from
Linoleic acid(PUFA) in
human body.
Proper Requirement
Of Fatty Acids To Human Body
It is ideal to consume ratio of:
1 : 1 : 1
SFA MUFA PUFAs
respectively from the diet to
maintain good health.
Naturally there is no single oil
which has all 3 types of fatty
acids in ideal proportion.
Hence it is always advisable to
mix a combination of oils
and consume.
Oils Rich In
Oils rich in
Oils rich in
SFAs
MUFAs
PUFAs
Coconut Oil
Olive Oil (75%)
Flax seeds/
Linseed Oil
Palm Oil
Sunflower Oil
Soya /Safflower
(85%)
Oil
Butter
Ground nut /
Almond Oil
Pea nut Oil
Animal Fat
Almond Oil
Rice Bran
Sesame Oil
Walnuts Oil
Beef Fat (Tallow
Corn Oil
Fat) 50%
Lard (Pork Fat)
Marine Fish
40%
Fatty Acids
Carbons Double
Abbreviation
Source
bonds
Acetic
2
0
2:0
bacterial metabolism
Propionic
3
0
3:0
bacterial metabolism
Butyric
4
0
4:0
butterfat
Caproic
6
0
6:0
butterfat
Caprylic
8
0
8:0
coconut oil
Capric
10
0
10:0
coconut oil
Lauric
12
0
12:0
coconut oil
Myristic
14
0
14:0
palm kernel oil
Palmitic
16
0
16:0
palm oil
Palmitoleic
16
1
16:1
animal fats
Stearic
18
0
18:0
animal fats
Oleic
18
1
18:1
olive oil
Linoleic
18
2
18:2
grape seed oil
Linolenic
18
3
18:3
flaxseed (linseed) oil
Arachidonic 20
4
20:4
peanut oil, fish oil
Functions/Role/Significance
Of Fatty Acids/PUFAS
1.Secondary Source Of Energy
Fatty acids/PUFAs are essential
components of different forms of
simple and compound lipids.
Fatty acids are highly reduced
compounds.
Oxidation of FAs in the body
provide secondary source of
energy (ATP).
2.Components Of Biomembranes
PUFAs are component of
Phospholipids.
Since the second Fatty acid in
Phospholipid is mostly PUFA.
PUFAs are important
constituents of biomembranes
of every body cell and cell
organelles.
PUFAs of membrane play
role in:(Less compact)
Membrane fluidity
Selective permeability
3.PUFAs Lower Blood Cholesterol
Levels
Essential Fatty acids lower
the serum levels of Cholesterol.
By esterifying Cholesterol.
Cholesterol ester is later
degraded and excreted out
through feces via bile.
4.PUFA Precursor for Eicosanoid
Biosynthesis
Arachidonic acid (20
Carbon PUFA) is a
precursor for
biosynthesis of various
Eicosanoids.
5.Structural Component Of Organs
PUFAs has role in Brain
development and its
functions.
Maintains the viability of
islet cells of Pancreas.
Essential fatty acids are
structural components of
gonads.
Lionlenic acid increases
vision.
Essential fatty acids prevents
Fatty Liver.
By helping in formation of
Lipoproteins and mobilizing
out the Lipids from Liver.
PUFAs prevents early ageing.
EFAs Prolongs Clotting time.
6.PUFAs Protect Heart
Dietary PUFAs are easily
metabolized in the body.
Since the double bonds are unstable
and easily cleavable.
PUFAs do not get accumulated in
the blood arteries and capillaries.
Thus PUFAs have low risk of
Atherosclerosis and Cardio
vascular disorders.
Deficiency Of PUFAs
Deficiency Of PUFAs is Rare.
May be Suffered by:
Infants :Not fed with natural milk
and natural food items.
But fed with formula diets which
have low fat content.
Adults : Eating poor diet not
containing PUFAs for long periods.
Phrynoderma /Toad Skin is due
to PUFA deficiency.
Phrynoderma /Toad Skin Symptoms
The skin becomes dry with lesions
(Scaly Dermatitis).
Presence of horny erruptions on the
posterior and lateral parts of limbs,
back and Buttock.
Loss of hair
Poor wound healing
Deficiency of Essential Fatty acids :
Affects every cell ,organ and
system
Growth retardation
Problems with reproduction
Skin lesions
Kidney and Liver disorders
Brain disorders/Behavioral
disorders.
Transportation Of Fatty Acids
Through Blood Circulation
Fatty acids Transportation In body
More than 90% of the fatty acids
found in plasma are in the form of
Fatty acid esters.
Fatty acids are in bound form as:
Triacylglycerol
Cholesteryl esters
Phospholipids
Bound form of Fatty acids
are Transported
through various
Lipoproteins.
Unesterified/Free Fatty acids
are very less amount in body.
FFA are transported in the
blood circulation in association
with Albumin.
Properties Of Fatty Acids
Solubility Of Fatty acids:
Solubility of Fatty acids depends upon :
The hydrocarbon chain length
Fatty acids with small chain length
are more soluble.
Solubility of Fatty
acids decreases
With increase in Fatty
acid hydrocarbon
chain length.
Acetic acid most simplest fatty
acid is soluble in water.
Palmitic acid ,Stearic acid are
insoluble in water.
Melting Point Of Fatty acids:
Melting point of a Fatty acid
depends upon:
Chain length of FA
Nature of bonds in hydro
carbon chain of FA.
Short and unsaturated
Fatty acids has low
melting point.
Long and Saturated Fatty
acids are has high melting
point.
Thus melting point of
Fatty acids(FAs):
Increases with increase
in chain length of FAs.
Decreases with decrease
in chain length of FAs.
Melting Points
Affected by chain length
Longer chain = higher melting temp
Fatty acid: C12:0
C14:0
C16:0
C18:0
C20:0
Melting point: 44?C
58?C
63?C
72?C
77?C
Structures and Melting Points of Saturated Fatty Acids
Melting Points
Affected by number of double bonds
More saturated = higher melting temp
Fatty acid:
C18:0
C18:1
C18:2
C18:3
Melting point:
72?C
16?C
?5?C
?11?C
Structures and Melting Points of Unsaturated Fatty Acids
Melting Point and Fatty Acid Composition of Some
Fats and Oils
Saturated Fatty acids has
straight and extended
conformation which can be
packed into compact structure.
More heat energy is required to
remove the compact structures
of Saturated Fats.
Unsaturated fatty acids has
rigid bends in its structure hence
not packed compactly.
Less heat energy is required to
separate these less compact
Unsaturated fatty acids.
Membrane Lipids are fluid by
consistency as they are more
composed of unsaturated
fatty acids.
Storage Lipids which are
anhydrous has Long saturated
Fatty acids.
Significance Of -COOH group
Of Fatty Acids
Saponification /Salt Formation
The Carboxyl groups of Fatty acids
reacts with strong Alkalies
KOH/NaOH
To form their Salts which are
Soaps.
This property is used for
commercial manufacture of
Soaps.
Ester Formation
The Carboxyl group of Fatty
acids reacts with Hydroxyl
groups of Alcohols
Glycerol/Sphingosine)
To form Esters bonds, of Simple
and Compound Lipids.
Fatty acids get esterified with Alcohols
to form various simple and compound
Lipids:
Triacylglycerol
Waxes: Cholesterol ester
Phospholipids
Glycolipids
Lipoproteins
Hydrogenation Of Fatty Acids
Hydrogenation of Fatty
acids is a conversion of
Double bonds of a
unsaturated fatty acid to
single saturated bonds.
Thus process of
Hydrogenation transforms
Unsaturated Fatty acids
to Saturated Fatty acids.
The process of
Hydrogenation also
transforms naturally
occurring Cis Fatty acids
to Trans Fatty acids.
Halogenation Of Fatty acids
Adding Halogens like
Cl, Br or I at double
bonds of UFAs and
making saturated.
The number of Halogen
atom taken up are
dependent on the
number of double
bonds in the structure
of Fatty Acid.
Significance Of Halogenation
Halogenation of fatty
acids is an index of
assessing the degree
of unsaturation
Iodine Number is a process of
Halogenation which checks the
content of SFA and PUFAs of
Fats and Oils.
SFA has zero Iodine number.
PUFAs has high Iodine number.
Geometric Isomerism Of
Unsaturated Fatty acids
Depending on orientation of
atoms or groups around the
axis of double bonds.
Cis form of Fatty acids
Trans form of Fatty acids
Cis Form Fatty acids
Most naturally occurring
UFAs are of cis form.
The groups around double
bond are on same side.
All Cis FA has an angle of 120
degree at the double bond.
Cis forms are L shaped
structures
(due to bend /kink in structure).
Phospholipids of biological
membranes contain Cis form
of fatty acids which has
kinks/bents .
This prevent compact packing
of fatty acid chains and are
responsible for the fluidity of
membranes.
Al -Cis Fatty acids
Good for Health
Human body contain Enzyme system to
metabolize Cis form of Fatty acids.
Cis forms when ingested through food are
easily metabolized and does not retain in
the body.
Hence good for health and no risk of
Atherosclerosis and CVD.
All Cis form of fatty acids are unstable
and easily metabolizable.
Trans Form Of Fatty acids
Trans fatty acid structures are
straight and has no bend.
The groups around the double
bonds are on opposite sides.
Trans form of fatty acids are
stable and less metabolizable.
Named According to Location of H's
Cis or trans fatty acids
Cis-9-octadecenoic acid
Trans-9-octadecenoic acid
(Oleic acid)
(Elaidic acid)
Cis and Trans Fatty Acids
H C
H 2C C H2
H 2C C H2
H 2C C H2
H 3C C H 2
Cis Fatty Acids
Trans form of Fatty acids
Less occur in natural
foods.
Obtained as byproducts of
Hydrogenation of oils.
More content of Trans Fatty acids are
found in processed foods viz:
Hydrogenated Oils (Vanaspati Dalda)
Ghee
Margarine
Bakery products /Fast foods
Deeply Fried recipes in Oils which
are prepared in repeatedly heated
oils.
Trans Fatty Acids
Detrimental to Health
Trans Fatty Acids
Not Metabolized Easily
Human body has no Enzyme system to
metabolize the Trans Fatty acids.
Foods ingested with rich concentration of
Trans fatty acids do not get metabolized.
Trans fatty acids get retained in body
tissues, blood vessels(harden the blood
vessels).
They increases risk of Atherosclerosis.
Block or reduce the blood supply to
tissues.
Trans fatty acids increases
risk of :
Atherosclerosis
Cardio Vascular disorders:
Ischemia
Myocardial Infarction
Stroke(Brain attack)
Study Of Derived Lipids
Alcohols
Alcohols Involved In
Lipid Structures
3 Alcohols Involved In Lipids
1. Glycerol
(C3-Trihydric Alcohol)
2. Sphingol/Sphingosine
(C18-Dihydric Alcohol)
3. Cholesterol
(C27-Monohydric Alcohol)
Alcohols Of Lipids
Are
Classified
As
Derived Lipids
Glycerol/ Glycerin
Glycerol [C3 ]is a POLYOL
Glycerol is chemically Trihydric
Alcohol (3 ?OH groups)
In human body Glyceraldehyde
on reduction gives Glycerol.
vGlycerol is a backbone of
Glycerol based Lipids viz:
v Triacylglycerol
v Glycerophospholipids
Glycerol is a
Derived Lipid
Obtained from
Hydrolysis of Simple
and Compound Lipids
SPHINGOSINE/SPHINGOL
Sphingosine is a C18, complex
Dihydric, Amino alcohol.
Serine provides NH2 group of
Sphingosine.
What Is a Ceramide?
A Fatty acid linked to an
amino group of Sphingosine
With an amide linkage form
a Ceramide.
Ceramide if linked to Phosphate
and Nitrogenous groups forms
Sphingophospholipids.
Ceramide linked to Carbohydrate
moieties form Glycolipids.
Sphingosine forms
Sphingolipids /Compound
Lipids with Alcohol Sphingol
Examples of Sphingolipids:
Sphingophospholipids
Glycolipids
Sphingosine is a derived
Lipid.
Obtained from Hydrolysis
of Sphingolipids
Sterols
Sterols are chemically
complex, cyclic ring
structures.
Sterols are complex
organic monohydric
Alcohols.
Examples Of Sterols
Cholesterol (Animal Sterol)
7 Dehydrocholesterol( Provitamin D)
Ergosterol (Plant Sterol)
Sitosterol (Plant Sterol)
Coprosterol (Excretory form of
Cholesterol)
Sterols have a parent ring
Cyclo Pentano Perhydro
Phenantherene (CPPP)
nucleus.
Common Sterol Compounds
Vitamin D3
(cholecalciferol)
Cholesterol
(a sterol)
Testosterone
Stigmasterol
(a steroid hormone)
(a phytosterol)
Cholesterol A Derived Lipid
Cholesterol is classified as
Derived Lipid.
It is derived from
Cholesterol Ester (Wax).
Cholesterol
Cholesterol is an Animal Sterol .
Cholesterol means Solid Alcohol as
it was first obtained from gall stones
of bile.
Cholesterol is richly composed in
Gall stones.
Structure Of Cholesterol
Cholesterol is complex cyclic
unsaturated, monohydric
Alcohol.
Its molecular formula is
C27H45 OH.
Cholesterol has parent nucleus
as Cyclo Pentano Per hydro
Phenantherene ring
system(CPPP).
The structure of CPPP has four
fused cyclic rings (A,B,C and D)
Hexane ring A,B,C is a
Phenatrene nucleus.
D ring is Cyclopentane
ring.
Pentahydrophenantrene (sterane)
The Structure of Cholesterol Possess:
1. Hydroxyl group (-OH) at C3.
2. Double bond between C5 and C6.
3. 5 Methyl (-CH3) groups.
4. A 8 Carbon side chain linked to C17
of the structure.
Cholesterol is the Most abundant Sterol
of Human body
Forms Of Cholesterol
Cholesterol exists in two forms:
Free Cholesterol - 30%
(Amphipathic form)
Cholesterol Ester - 70%
(Non polar form)
Properties Of Cholesterol
Cholesterol is white or pale
yellowish, crystalline ,odorless
compound.
Insoluble in water and soluble in
organic solvents like Ether and
Chloroform.
It forms crystal of rhombic plates
with notched edges.
Qualitative Tests Of Cholesterol
detection are:
Liebermann Burchard Reaction
Salkowski Reaction
Zak's Reaction
Sources Of Cholesterol
To Human Body
Exogenous Sources of Cholesterol:
Animal Origin Food Items
Endogenous Source Of Cholesterol:
Obtained In well fed condition from
Excess Glucose
Dietary Sources Of Cholesterol
Cholesterol is
exclusively present in
animal body hence it is
an animal sterol.
The dietary rich sources of Cholesterol
are animal origin foods like:
Egg Yolk
Meat
Milk
Butter
Cream
Remember
Cholesterol is absent
in plant origin food
items.
Occurrence and Distribution Of
Cholesterol in the Body
Cholesterol is richly present in Nervous
tissue Brain.
Other organs containing Cholesterol are:
Intestinal Mucosal cells
Skin
Liver
Adrenal Cortex
Gonads
70 % of Cholesterol
associated with cellular
components
30 % of Cholesterol is in the
plasma.
Transportation Of Cholesterol
Cholesterol in blood is
transported by :
HDL and LDL
Functions Of Cholesterol
Cholesterol is the
constituent of
biomembranes of the
cell and has structural
importance.
Cholesterol richly
present in nervous
tissue and covers
Myelin sheaths.
Cholesterol helps in nerve
impulse transmission since:
It has high dielectric
constant.
It is a poor conductor of
heat and electricity.
Cholesterol Serve Precursor for
Biosynthesis Of Many Steroids
Steroids
Steroids are derivatives of
Sterols.
Chemical Compounds
obtained from Cholesterol
are termed as Steroidal
compounds.
Examples of Steroidal Compounds
Vitamin D (Cholecalciferol)
Bile acids (Cholic and Chenodeoxycholic
acid)
Bile Salts are obtained from Bile acids.
Steroidal Hormones
ACTH
Mineralocorticoids
Glucocorticoids
Sex Hormones: Androgens, Progesterone,
Estrogen and Testosterone
Bile Acids and Bile Salts
Steroids Hormones
Disorders Related To Cholesterol
Serum Total
Cholesterol of a
Healthy human body
is 150-200 mg%
Hypercholesterolemia
Causes for Hypercholesterolemia
High intake of dietary cholesterol(animal origin)
is a exogenous source of Cholesterol.
Elevated endogenous Cholesterol biosynthesis
when a very rich Carbohydrates is ingested.
Defect in Cholesterol transport by Lipoproteins
in blood retains Cholesterol in blood.
Hypercholesterolemia leads to :
Deposits of excess of Cholesterol in
blood vessels.
Atherosclerosis and atheroma
/plaque formation.
Increased risk of ischemia and
Myocardial infarction and Stroke.
Cholesterol Summary
Cholesterol is exclusively found only in
animals.
Exogeneous Cholesterol comes from diet
Endogeneous Cholesterol is
biosynthesized by the Liver from
Glucose product Acetyl-CoA.
Cholesterol is an important component
of biomembranes, steroidal
hormones, bile acids and Vitamin D
Study Of
Simple Lipids/Neutral Lipids
Fats/Oils
Fats and Oils are simple
/Neutral lipids
Fats/Oils are chemically
esters of Fatty acids with
Alcohol Glycerol
(Trihydric Alcohol).
Chemically Fat/Oil
is Triacylglycerol
(TAG).
Fatty acids are Stored
as components of Triacylglycerols
Fatty acids are not stored in
free form in living beings.
Fatty acids are stored in
bound form as TAG.
Thus TAG is a storage form
of Fatty acids .
Fatty acids are linked
to an Alcohol Glycerol
by ester bonds to form
Triacylglycerol (TAG).
Three Fatty acids same or
different (Acyl Chains) are
esterified
With three hydroxyl groups of a
Glycerol to form Triacylglycerol
(TAG)/Triglycerides(TG).
Hydrolytic Products Of TAG
Monoacylglycerol (MAG)
/(Monoglycerides): A Glycerol
esterified with one fatty acid.
Diacylglycerol (DAG)
(Diglycerides):
A Glycerol esterified with two fatty
acids.
MAG and DAG are derived
Lipids.
Monoacylglycerol and
Diacylglycerol are hydrolytic
products of Triacylglycerol.
These are produced during TAG
metabolism in the body.
Most Common Fatty Acids in Triacylglycerol
Fatty acid
Carbon:Double bonds
Double bonds
Myristic
14:0
Palmitic
16:0
Palmitoleic
16:1
Cis-9
Stearic
18:0
Oleic
18:1
Cis-9
Linoleic
18:2
Cis-9,12
Linolenic
18:3
Cis-9,12,15
Arachidonic
20:4
Cis-5,8,11,14
Eicosapentaenoic
20:5
Cis-5,8,11,14,17
Docosahexaenoic
22:6
Cis-4,7,10,13,16,19
CH3(CH2)n COOH
Differences In Fat and Oil
Fat and Oils are different in
Physical Characteristics
Fat is solid at room temperature.
Oil is liquid at room
temperature.
Chemical Name of Both Fats and Oils is
Triacylglycerols:
TAG of Fat is solid since chemically
composed of long and saturated fatty
acids.
Source of Fat is Animal foods.
TAG of Oil is liquid as composed of short
and unsaturated fatty acids.
Source of Oil is plant.
Chain Length Of Fatty acids
IN TAG affects Melting Point
The chain length of the majority of Fatty acids
will determine the "hardness" of the Fat/TAG.
<10 carbons in FA = liquid
>20 carbons in FA = solid
Acetic Acid (2 C)
Vinegar
Liquid
Stearic Acid (18 C)
Beef Tal ow
Solid
Arachidic Acid (20 C) Butter
Solid
Chemical Structures Of
Triacylglycerol (TAG)
Triacylglycerol is formed by linking of
Three same or different fatty acids
to a Glycerol molecule by ester
bonds.
The Carboxyl group of each fatty
acid interacts with hydroxyl group
of Glycerol(Trihydric Alcohol) to
form Ester bond of TAG.
Types Of Triacylglycerol
Simple TAG
Mixed TAG
Simple TAG: Three same Fatty
acids are esterified to Glycerol to
form simple TAG.
Examples of Simple TAG:
TriPalmitin
TriStearin
TriOlein
Olive Oil Rich In Simple TAG
Olive oil contains mostly TAG as Triolein, which
has three Oleic acids.
Mixed TAG:
The 3 different Fatty acids
esterified to Glycerol to form a
mixed TAG.
Mixed TAG's are more
predominant in nature.
In a Mixed TAG
First Carbon C1 -has Saturated Fatty
acid
Second position C2-has Unsaturated
Fatty acid-PUFA
The 3 rd position C3 Fatty acid in
TAG has- either
Saturated/Unsaturated fatty acid
TAG is Neutral or Non
polar lipid.
Since TAG structure
has no charged/polar
group in its structure.
Sources OF Triacylglycerol
To
Human Body
Exogenesis source of TAG :
Dietary Fat/Oil
Endogenous source of TAG :
Liver Lipogenesis in well fed
condition
Using Glucose product
Acetyl-CoA.
Dietary Sources Of TAG
Animal Fat (Solid)
Plant Oils (Liquid)
Fats (solid Triacylglycerol)
Oil (a liquid Triacylglycerol)
Occurrence/Distribution Of TAG
qTAG is a most widely
distributed abundant
natural lipid.
The predominant Lipid
form in Human diet is
TAG 98%.
95 % of human body
Lipid is TAG.
Storage form of Lipid in
human body is TAG.
Because of insolubility of TAG
in aqueous phase:
Body TAG are mostly found in
isolated compartments as
droplets.
TAG in anhydrous form is
packed in Adipocytes
(Depot Fat)
Transportation Of TAG in blood
is By Lipoproteins
Chylomicrons :
Transports exogenous dietary TAG
VLDL:
Transports endogenous TAG
Biomedical Importance Of TAG
Triacylglycerol is the
predominant form
of dietary Lipid
(99%).
1.TAG Serves As Source Of Energy
TAG serve as secondary
source of energy when
body Glucose get lowered.
TAG has high calorific value
(9Kcal/gram) more than
Carbohydrates (4 Kcal/gram ).
2.TAG Reservoir Of Energy
TAG When excess serves
as an energy reservoir
stored in Adipocytes as :
Unlimited amount
Concentrated
Anhydrous form
Stores of TAG are
utilized in between
meals and starvation
phase.
A good storage of depot
Fat can suffice for 2-3
months in starvation
condition.
TAG is highly reduced
and anhydrous form.
Hence chosen as energy
reserve of the body.
3.Store House Of TAG
is High
In Comparison To
Glycogen Stores
TAG is stored in anhydrous
form .
More content of energy can be
stored by TAG in comparison to
Glycogen stores.
1 gm of anhydrous TAG
stores more than 6
times as much as energy
as 1 gm of hydrated
Glycogen.
Hydrated molecules requires more space.
TAG stored in anhydrous form
requires less space.
In contrast Glycogen being hydrated
requires more space.
(1 gm of Glycogen binds with 2gm of water)
The stored TAG is used as long
term energy source for body
activities.
In long marathon race energy
for muscle activity is provided by
the hydrolysis of depot TAG.
4. TAG Regulates Body
Temperature
The subcutaneous Fat layer is a
TAG
TAG is a bad conductor of heat
and electricity and serves as a
thermal and electrical insulator.
Which prevents loss of heat from
the body and plays important role
in regulating body temperature.
5.TAG Protects Internal Visceral
Organ and Systems
A presence of Fatty (TAG)
pad around the soft
delicate internal visceral
organs
Protects from mechanical
trauma or injury by acting
as a shock absorber.
TAG provides shape
to body and keep the
skin smooth and
supple.
Remember TAG is
not associated to
biomembranes.
Tests To Check Purity
Of
Fat and Oil
Several laboratory tests are
employed to:
Check the purity
Degree of adulteration
of fats and oils.
These tests also
determine the
biological value of Fat.
Iodine Number
Iodine number is
Grams/Number of Iodine
absorbed by 100 gram of Fat
/Oil .
Iodine Number is calculated by
method of Iodometry.
Use Of Iodine Number
Iodine number is useful to
know
The index of unsaturation
and content of unsaturated
fatty acids present in the
Fat/Oil.
Iodine number is directly
proportional to the
unsaturated bonds of PUFAs in
a Fat/Oil.
High value of Iodine number
of oil indicates more content of
Unsaturated Fatty acids in it.
Name Of Oils
Iodine Number
Coconut Oil
7-10 (Least)
Butter
25-28
Ground Nut Oil
85-100
Sunflower Oil
125-145
Soya bean Oil
135-150
Linseed Oil /Flax seed 175-200 (Highest)
Oil
Determination of Iodine number helps
in knowing the degree of
adulteration of tested oil sample.
If Linseed oil is adulterated with an
oil whose content is high in saturated
fatty acids will give lower Iodine
number than the reference values.
Saponification Number
Saponification number is
milligram/number of KOH
molecules required to hydrolyze
and saponify one gram of Fat/Oil.
The saponification number
gives the idea of molecular
size/chain length of Fatty
acids present in 1 gram of Fat.
1 gram Fat/Oil with long
chain fatty acids has low
saponification number.
Since in 1 gram of Fat has few
-COOH groups of fatty acids
to react with KOH.
1 gram Oil with short chain
fatty acids has higher
saponification number.
Since it has more COOH groups
for KOH reaction.
1 gram of Fat/oil with long
chain fatty acids has lower
saponification number.
As compared to an 1 gram of oil
containing short chain fatty
acids.
Oils
Saponification
Number
Coconut Oil
250-260
Butter
230-250
Jojoba Oil
69- 80
Olive Oil
135-142
Acid Number
Acid number is milligram of
KOH required for complete
neutralization of free fatty
acids present in one gram of
Fat/Oil.
Acid number checks the purity of
Refined oils.
Refined oils are free from free
fatty acids and has zero Acid
number.
Increased Acid number of refined
oil suggests bacterial/chemical
contamination and unsafe for
human consumption.
Reichert Meissl (RM)Number
RM number is 0.1 N KOH
required for complete
neutralization of soluble
volatile fatty acids
distilled from 5 gram of
Fat .
R.M Number of
Butter is 25-30.
The R.M number of
other edible oils is
less than 1.
R.M number is useful in
testing the purity of butter
Since it contains good
concentration of free volatile
fatty acids viz: Butyric,
Caproic and Caprylic acid.
Adulteration of
butter reduces its
R.M number.
Chain Length Of Fatty acids
Of TAG affects Melting Point
The chain length of the majority of fatty acids
will determine the "hardness" of the Fat/TAG.
< 10 carbons in FA = liquid
>20 carbons in FA = solid
Acetic Acid (2 C)
Vinegar
Liquid
Stearic Acid (18 C)
Beef Tallow
Solid
Arachidic Acid (20 C)
Butter
Solid
Hydrogenation Of Fat/Oil
Treatment of Oils(TAG) rich in PUFAs
with Hydrogen gas, (H2).
Catalyst required (Nickel).
Adding Hydrogen at double bonds of
PUFAs.
It is also called "Hardening of Oils"
Hydrogenation also converts PUFAs with
cis form to trans form.
Margarine
Vanaspati Dalda Crisco, Spry, etc.
Advantages and Disadvantages Of
Hydrogenation Of Fat /Fatty acids
Advantage Of Hydrogenation
Commercially Oils with
Unsaturated Fatty acids are
Hydrogenated to
Saturated Fatty acids.
Hydrogenation makes the
unstable ,unsaturated , liquid
TAGs:
To stable , saturated, solid TAGs
Increases shelf life
Reduces risk of Rancidity
Example : Vanaspati Dalda
,Margarine.
Double bond containing
/Unsaturated Fatty acids are
unstable and ready for
peroxidation and rancidity.
Single bond containing/Saturated
Fatty acids are stable and less
peroxidized and made rancid.
Disadvantage Of Hydrogenation
Of Fat/Fatty acids
During Hydrogenation
some of the Cis form
Fatty acids are
transformed to Trans
Fatty acids.
Trans Fats increases the risk of
Atherosclerosis and CVD.
Hydrogenated trans Fatty
acids are more stable.
Body has no enzyme system
to oxidize and metabolize
trans fatty acids.
Thus trans Fats containing trans
Fatty acids are:
Less metabolized in body.
More retained in the body.
Leading to Atherosclerosis and
CVD.
Remember
Hydrogenated
Fats are Bad for
Health.
Note
Try eat natural Fats.
Avoid Processed Fats.
Summary Of Hydrogenation:
Hydrogen atoms are added to unsaturated
Fatty acids
Make liquid oils more solid and more
saturated.
Create trans fatty acids.
Reduce oxidation of Fatty acids.
Resist rancidity.
Increase risk of cardiovascular disease.
Rancidity Of Fats/Oils
Rancidity
Rancidity is a physico
chemical phenomenon
Which deteriorates Fats and
Oils
Resulting in unpleasant taste
,odor and color of Fat/Oil
(Rancid Fat/oil)
Rancid Fat is inedible
Factors Causing Rancidity
Causes Of Rancidity
Fats and Oils get Rancid on Ageing.
Various Factors aggravates rancidity of
Oils and Fats:
Improper handling by exposure to:
Light
Air
Moisture
Microbes
Oxygen is favorable for Rancidity
PUFAs are more prone to
Rancidity
Types and Mechanism
Of Rancidity
Types Of Rancidity
Oxidative Rancidity
Hydrolytic Rancidity
Ketonic Rancidity
Oxidative Rancidity:
PUFAs having double bonds are
easily oxidized to form its
peroxides.
By the action of Oxygen
Derived Free radicals (ODFR).
The cellular Lipids are also
likely to get peroxidized by
Free radical action causing
damage to biomembranes.
Hydrolytic Rancidity:
Long Chain Saturated fatty acids
are hydrolyzed by bacterial
Enzymes .
To produce Dicarboxylic
acids, Aldehydes, Ketones etc
which make the Fat rancid.
Ketonic Rancidity
It is due to the contamination with
certain Fungi such as Asperigillus
Niger on Oils such as Coconut oil.
Ketones, Fatty aldehydes, short
chain fatty acids and fatty alcohols
are formed.
Moisture accelerates Ketonic
rancidity.
Rancidity gives bad odor and
taste to rancid Fats/oils.
Due to Dicarboxylic acids
,Ketones , Aldehydes
Produced during the process of
Prevention Of Rancidity
Rancidity can be
prevented by proper
handling of oils
By keeping fats or oils in
well closed containers in
cold, dark and dry place.
Prevention Of Rancidity
Avoid exposure to direct
sunlight, moisture and air.
Avoid over and repeated
heating of oils and fats.
Removal of catalysts such as
Lead and Copper from Fat/Oils
that catalyzes rancidity
prevents rancidity.
Antioxidants Prevent Rancidity
Antioxidants are
chemical agents which
prevent the
peroxidation and
Hydrolysis of Fats/Oils.
Examples Of Antioxidants:
Tocopherol(Vitamin E)
Vitamin C
Propyl Gallate
Alpha Napthol
Phenols
Tannins
Hydroquinone's.
Butylated Hydroxy Anisole(BHA)
Butylated Hydroxy Toluene (BHT)
The most common natural
antioxidant is vitamin E
that is important in vitro
and in vivo.
Vegetable oils are associated with
high content of natural
antioxidants (Vitamin E),
Hence oils do not undergo
rancid rapidly
As compared to animal fats which
are poor in naturally associated
antioxidants .
Addition of Anti-oxidants
prevents peroxidation in
fat (i.e., rancidity).
Rancidity of Fats and Oils is
prevented by adding
Antioxidants.
Thus addition of
Antioxidants increases shelf
life of commercially
synthesized Fats and Oils.
Avoidance of Rancidity of Fat/Oil By :
q Good storage conditions
q Less Exposure to light
q Low Oxygen, moisture
q No very High temperatures
q No Bacteria or fungal contamination
q Addition of Antioxidants
Hazards of Rancid Fats:
1. Rancidity destroys the content of
polyunsaturated essential fatty acids.
2. Rancidity causes economical loss because
rancid fat is inedible.
3. The products of rancidity are toxic, i.e.,
causes food poisoning and cancer.
4. Rancidity destroys the fat-soluble
vitamins (vitamins A, D, K and E).
Lipid Peroxidation
Is a source of Free Radicals
Lipids undergo
peroxidation(autoxidation) when
exposed to Oxygen.
The oxygen derived free radicals
(RO.,OH.,ROO.) with unpaired
electrons leads to chain reactions of
lipid peroxidation.
Steps of Lipid peroxidation
reaction:
Initiation
Propagation
Termination
Lipid peroxidation
Provide continuous Free
radicals.
Thus has potentially
devastating effects in the
body.
In vitro peroxidation of Lipids
deteriorates the quality of
Fats and Oils
Makes the Fat/Oil rancid and in
edible.
Fat/oil has bad taste and odor
Decreases the shelf life of Fats and
Oils.
In vivo peroxidation of membrane
Lipids damages the tissues.
Lipid peroxidation has devastating
effects on body Lipids.
Increases risk of Inflammatory
diseases
Ageing
Cancer
Antioxidants control and reduces
In vivo and In vitro Lipid peroxidation.
Naturally occurring antioxidants are :
Vitamin E
Vitamin C
Beta Carotene
In Vivo Enzymes as Antioxidants:
Catalase
Glutathione Peroxidase
Superoxide Dismutase
In vivo other Substances as Antioxidants:
Urate
Bilirubin
Food Additives as Antioxidants:
Alpha Naphtol
Gallic Acid
BHA
BHT
Preventive Antioxidants:
Reduces the rate of Chain
initiation of Lipid peroxidation
Catalase
Peroxidase
EDTA
DTPA
Chain Breaking Antioxidants:
Interferes the chain
propagation of Lipid
peroxidation.
Vitamin E
Urate
Differentiation Between
Fats And Oils
Fats
Oils
Fats are TAGs composed of Long Oils are TAGs composed of short
and Saturated Fatty acid.
and Unsaturated Fatty acids.
Fats solid at room temperature
Oils liquid at room temperature
Fat has high melting point
Oils have low melting point
Fats -animal In Origin
Oils -Plant in Origin
Example: Lard (pork Fat)
Example: Safflower Oil
Fats has low antioxidant
Oils have high antioxidant
content and get easily Rancid
content and do not get easily
Rancid
Fats are more stable
Oils are less stable
Fats are less metabolizable in
Oils are readily metabolizable
body.
in the body.
High content of dietary Fats has Oils have low risk for
high risk for Atherosclerosis.
Atherosclerosis.
Study Of
Compound Lipids
Compound Lipids
Compound lipids are class of
Lipids
Which are chemically Esters
of Fatty acids with Alcohols
attached with Additional
groups.
Additional Groups in Compound Lipids
may be either of these:
Phosphoric acid
Nitrogenous Base
Carbohydrate moieties
Proteins
Sulfate groups
3 Main Compound Lipids
Phospholipids
Glycolipids
Lipoproteins
Phospholipids
Phospholipids (PL)
Phospholipids (PL) are
compound lipids.
Phospholipids Chemically
Possess:
Fatty acids esterified to Alcohol
and
Phosphoric acid attached with
Nitrogenous /non nitrogenous
base.
Types Of
Phospholipds
Based upon the Alcohol present in
Phospholipid structure
Two Types of Phospholipids are :
Glycerophospholipids:
Glycerol containing Phospholipids
Sphingophospholipids:
Sphingosine/ Sphingol containing
Phospholipids.
Glycerophospholipids/
Glycerophosphatides
Simplest Glycerophospholipid
PHOSPHATIDIC ACID
Depending upon the Nitrogenous
and Non nitrogenous moiety
attached.
Examples of 7 Glycerophospholipids are:
1. Phosphatidic Acid (Simplest PL)
2. Phosphatidyl Choline (Lecithin)
3. Phosphatidyl Ethanolamine (Cephalin)
4. Phosphatidyl Serine
5. Phosphatidyl Inositol/ Lipositol
6. Phospatidal Ethanolamine/ Plasmalogen
7. DiPhosphatidyl Glycerol /Cardiolipin
Structures
OF
Glycerophospholipids
Phosphatidic Acid
Phosphatidic acid is a simplest
GlyceroPhospholipids.
Phosphatidic acid has Glycerol
esterified with two Fatty acids at C1
and C2 .
C3 is esterified with Phosphoric acid.
PHOSPHATIDIC ACID
Phosphatidic acid serve as
a precursor for the
synthesis of all other
Glycerophospholipids
Either by linking of
Nitrogenous or a Non
nitrogenous base.
Phosphatidyl Choline/Lecithin
Phosphatidyl Choline
(Lecithin) is the most
commonest and abundant
Glycerophospholipid in body.
Phosphatidyl Choline is commonly
called as Lecithin.
Derived from word `Lecithos'
meaning Egg Yolk.
Phosphatidic acid is linked to a
Nitrogenous base Choline to form
Phosphatidyl Choline.
Phosphatidyl Ethanolamine/
Cephalin
Phosphatidyl Serine
An Amino acid Serine
linked to Phosphatidic
acid forms Phosphatidyl
Serine.
Cephalins
Type of Glycerophospholipids
Nitrogen base is Ethanolamine
or Serine.
Phosphatidylethanolamine and
Phosphatidylserine are
Cephalins.
Phosphatidyl Inositol/Lipositol
Inositol a Polyol derived from
Glucose
It is a Non Nitrogenous ,
Carbohydrate Derivative.
Inositol linked to Phosphatidic
acid forms
Phosphatidylinositol.
Phospahatidyl Inositol 3,4,5
Tri Phosphate (PIP3) in
presence of enzyme
Phospholipase C
Generates Diacyl Glycerol and
Inositol Tri Phosphate.
Phosphatidalethanolamine/
Plasmalogen
Plasmalogen possess an Ether
linkage at C1.
Fatty acid is linked to C1 of
Glycerol, by an Vinyl(CH=CH2)
Ether (C-O-C)linkage instead of
usual Ester bond.
Nitrogen base linked are
Ethanolamine/Choline.
Diphosphatidylglycerol/
Cardiolipin
Cardiolipin was first isolated from
Cardiac Muscles of Calf and
hence the name derived.
Diphosphatidylglycerol/Cardiolipin
is chemically composed of
Two molecules of Phosphatidic
acid linked to one Glycerol .
SphingoPhospholipids/
Sphingophosphatides
Sphingophospholipid is a
type of Phospholipid.
Sphingophospholipid is
Sphingosine based Lipid
Which has an C18 Dihydric
Amino Alcohol?
Sphingosine.
Sphingomyelin is an
example of
Sphingophospholipid.
Sphingosine is linked with a
Fatty acid by an amide linkage
to form Ceramide.
Ceramide is then linked to
Phosphoric acid and Choline
to form Sphingomyelin.
Properties Of Phospholipids
Amphipathic Nature Of PL
Phospholipds are
Amphipathic/ Amphiphillic in
nature.
Since the structure of PL possess
both polar and nonpolar
groups.
Hydrophilic/Polar groups
of Phospholipids:
Phosphoric acid
Nitrogenous groups
Hydrophobic/non polar
groups of Phospholipids :
Fatty acid/Acyl chains
Functions Of Phospholipids(PL)
1. Biomembrane Components
2. Lung Surfactant Role
3. Lipid Digestion and Absorption
4. LCAT activity for Cholesterol Esterification and
Excretion
5. Lipotropic Factor
6. Clotting Mechanism
7. Cardiolipin role
8. Coenzyme Role
9. Choline from Lecithin Methyl Donor
10. Detoxification role of Lecithin
11. Eicosanoids biosynthesis
12. Nerve Impulse Conduction
13. Second Messenger of Hormone Regulation
Glycerophospholipid Functions
1. Phospholipids Components Of
Biomembranes
Role Of Lecithin
The Glycerophospholipid
Lecithin is the major structural
components of biomembranes.
The Amphipathic phospholipid
bilayer has polar head groups of PL
directed outwards.
Lipid bilayer of plasma membrane
Membrane Phospholipid bilayer
,constituent of cell membranes
imparts:
Membrane Structural Integrity
Membrane Fluidity
Membrane Flexibility
Selective Permeability
Phospholipids may have
fatty acids which are
saturated or unsaturated.
This affects the properties of
the resulting bilayer/cell
membrane:
Most membranes have
phospholipids derived from
unsaturated fatty acids.
Unsaturated fatty acids add
fluidity to a bilayer since
`kinked' tails do not pack
tightly together.
Phospholipids (PL) derived from
unsaturated phospholipids al ow faster
transport of nonpolar substances across
the bilayer.
Polar substances are restricted to cross
the membrane .
PL bilayer in membranes protect the cel
from an entry of polar reactive and
interfering substances and serve as
security guards of cel s.
Membranes of nerve cells,
which are stiffer contain a much
higher percentage of
phospholipids derived from
saturated fatty acids.
They also contain high levels of
cholesterol which stiffens
membrane structure.
Cholesterol intercalates among the
Phospholipids.
Cholesterol fills in the spaces left by the kinks of
PUFAs .
Cholesterol stiffens the bilayer and makes
membrane less fluid and less permeable.
Diagram of a section of a bilayer membrane.
2.Phospholipid As Lung Surfactant
DiPalmitoyl Phosphatidyl
Choline serve as an Lung
surfactant.
It lowers the surface tension and
keeps the alveoli of lungs blown.
(prevent adherence of alveoli)
This enables effective exchange
of gases (Oxygen) in Lungs.
After expiration of air the
alveoli gets deflated.
The lung surfactant
reduces the surface tension
and allow the alveolar
walls to reinflate.
The Phospholipid as
Lung surfactant
prevent the body to
suffer from Respiratory
Distress Syndrome.
3.Phospholipids
Help In Digestion And Absorption
Of Dietary Lipids
Phospholipids being
amphipathic in nature act as
good emulsifying agents.
Along with Bile Salts they help
in digestion and absorption of
non polar dietary Lipids.
4.Phospholipids Helps In
Cholesterol Excretion
Lecithin helps in Cholesterol
Esterification by LCAT
activity.
Cholesterol Ester is later
dissolved in Bile and further
excreted it out.
Lecithin serve as a storage
depot of Choline.
Choline is a store of labile
Methyl groups
Hence Choline participate in
Transmethylation reactions .
Choline is used for generation of
neurotransmitter `Acetyl Choline"
which helps in nerve impulse
transmission.
Choline serve as Lipotropic factor
hence helps in Lipoprotein formation
in Liver to mobilize out Lipids and
prevent from Fatty Liver.
6. Phospholipids Releases
Arachidonic Acid For Eicosanoid
Biosynthesis
Lecithin at 2nd carbon has
Arachidonic acid(PUFA).
It donates Arachidonic acid
which is a precursor for
Eicosanoid biosynthesis.
Phosphatidyl Inositol also
provides Arachidonic acid
for Eicosanoids biosynthesis.
Lecithin helps CYT450
system for drug
detoxification.
8. Phospholipids Has Role
In Blood Coagulation
Role Of Cephalin
Phosphatidyl
Ethanolamine has role in
blood coagulation.
It converts clotting factor
Prothrombin to
Thrombin by factor X.
Phosphatidyl Serine has
role in Apoptosis
(Programmed Cell death).
10.Role Of Phospholipids In
Hormonal Action
Role Of Phosphatidylinositol
Phosphatidyl Inositol
Triphosphate (PIP3) is a
constituent of cell membrane
and mediate hormone action
and maintain intracellular
Calcium.
Inositol tri phosphate and
Diacylglcerol are released from PIP3
by membrane bound Phospholipase C
The Inositol triphosphate and DAG
serve as second messenger to
hormones Oxytocin and Vasopressin.
Plasmalogen
associated to brain
and muscles helps in
Neural functions.
Role Of Cardiolipin
Cardiolipin is rich in inner
mitochondrial membrane
and supports Electron
Transport Chain and
cellular respiration.
Cardiolipin exhibits
antigenic properties and
used in VDRL
serological tests for
diagnosis Syphilis.
Phospholipid serve as
Coenzyme for certain
Enzymes :
Lipoprotein Lipase
Cytochrome Oxidase
Functions OF
Sphingophospholipids
Sphingomyelins are rich in
Myelin sheaths which
surrounds and insulate the
axons of neurons.
Sphingomyelin helps in nerve
impulse transmission.
Disorders Related To Phospholipids
Respiratory Distress Syndrome
(RDS)
Suffered by premature born infants.
Caused due to deficiency of Lung
surfactant DiPalmitoyl Phosphatidyl
Choline.
Since Lung is the last organ to
mature.
Premature babies has insufficient
lung surfactant lining in the alveoli
walls.
Which supports no normal
respiration.
Has respiration difficulties due to
alveolar collapse.
Sign And Symptoms Of
RDS
Low ATP production
Weakness ,Lethargy
Low Cellular Functions
Poor Coordination
L/S ratio of Amniotic Fluid
Diagnostic Criteria For RDS
Lecithin /Sphingomyelin
(L/S) ratio of amniotic
fluid is a good indicator
to evaluate fetal lung
maturity.
Prior to 34 weeks of gestation the
concentration of Lecithin and
Sphingomyelin in amniotic fluid is
equal.
In Later weeks of gestation the
Lecithin levels are markedly
increased.
At full term L/S ratio is 5.
In pre term infants L/S
ratio is 1 or < 1 resulting
to suffer from RDS.
Old age persons and Adults with
Lung damage
(Due to Smoking/ Infections)
Who unable to biosynthesize
the lung surfactant may also
exhibit RDS.
Membrane Related Disorders
Due To Defective Phospholipds
Deranged Cellular
Environment
Cell membrane Damage
Tissue Necrosis
Cell Death
Mitochondrial ETC Defects due to
Phospholipid Deficits
Defect In Sphingomyelins affect
Nerve Impulse Conduction
Fatty Liver due to Phospholipid
Defects.
Glycolipids
Glycolipids
Glycolipids are type of
compound Lipids.
Chemically Esters of Fatty
acids with Alcohol and
additional group as
Carbohydrate moieties
Types OF Glycolipids
Based on Alcohol
1. Glycoglycerolipids
Glycerol as Alcohol
( Less in Animals and Human)
2. Glycosphingolipids
Sphingosine as Alcohol
(Predominant in Animals and Human)
Glycosphingolipids
Predominant Animal Glycolipids
Types of Glycolipids
chemically composed of
Ceramide linked with one
or more sugar residues
/there derivatives
Types Of Glycosphingolipids
1. Based on Number and Type
of Carbohydrate moiety
and there derivatives
linked to a Ceramide
2. Based on Fatty acid in
Ceramide
Types Of Glycosphingolipids
Al has Ceramide in Their Str
1) Cerebrosides
2) Gangliosides
3) Globosides
4) Sulfatides
Cerebrosides
Simplest GlycoSphingolipids
Monoglycosylceramide
Cerebrosides
Cerebrosides are type of
Glycosphingolipids
Ceramide linked with one
sugar residue
Types of Cerebrosides
Depending upon the Carbohydrate
moiety Types of Cerebrosides are:
Glucocerebrosides
(In Extra neural/Other tissues)
Galactocerebrosides
(In Neural)
Structures Of Cerebrosides
Galactocerebroside
Depending upon the Fatty acids
Types of Cerebrosides are:
Kerasin-Has Lignoceric acid
Cerebron-Has Cerebronic acid
Nervon-Has Nervonic acid
Oxynervon - Has Oxynervonic acid
Gangliosides
Complex Glycosphingolipids
Gangliosides
Gangliosides are Type of
Glycosphingolipids
In comparison to
Cerebrosides, Gangliosides
are more complex.
NANA in Gangliosides
Characteristic feature of
Gangliosides is
Its structure contains one or
more N-Acetyl
Neuraminic Acid
(NANA)/Sialic acid
residues
NANA/Sialic acid is
derived from N-Acetyl
Mannose and Pyruvate.
Gangliosides structure has
Carbohydrate moieties as
Glucose
Galactose
N-Acetyl Galactosamine
N-Acetyl Neuraminic Acid
(NANA)/Sialic acid.
Types Of Gangliosides
Based on Number and
Position of NANAs in
Ganglioside structure
Various types and subtypes
of Gangliosides are existing
in human body
Types of Gangliosides
Gangliosides with one NANA residue
GM1
GM2
GM3
Gangliosides with two NANA residues
GD
Gangliosides with three NANA residues
GT
Types Of Gangliosides
Depending upon the Chemical structure
and Chromatographic separations
More than 30 Types of Gangliosides are
isolated:
Structure Of Gangliosides
GM3 is more common
and simplest
Ganglioside.
GM3 has single Sialic acid.
GM1 is a more complex
Ganglioside.
GM1 is obtained from GM3.
Occurrence Of Glycolipids
Glycosphingolipids are widely
distributed
In every cell and tissue of human
body
They are richly present in nervous
cells.
Occur particularly in outer leaflet of
Cell membrane.
Glycolipids occur on
the outer surface of
every cell membrane as
component of
Glycocalyx /(Cell raft).
Cerebrosides: Richly present in
White matter of brain
Myelin sheath
Gangliosides: Predominantly
present in
Grey matter of brain
Ganglions and Dendrites
Functions Of Glycolipids
Glycolipids are richly
present in nervous tissue,
they help in:
Development and
function of brain.
Nerve impulse conduction
Glycolipids present in cell
membranes Serve as :
Antigens viz Blood group
Antigens, Embryonic Antigen.
Receptor sites for Hormones.
Glycolipids of cell membrane serve
as:
Markers for cellular recognition
which helps in:
Cell Functioning
Cell Growth and Differentiation
Cell-Cell interaction
Cell Signaling/Signal Transduction
Anchoring sites for Antigens,
Toxin and Pathogens
GM1 serve as receptor
/anchoring site to :
Cholera toxin
Tetanus toxin
Influenza viruses
The Cholera toxin on
binding to intestinal cells
Stimulates secretion of
Chloride ions into gut
lumen.
Resulting in copious
diarrhea of Cholera.
In various malignancies
dramatic changes in
membrane Glycolipid
composition are noted.
Lipid Storage Disorders
Related To Glycosphingolipids
Disorders Of Glycolipids
Gaucher's Disease
Tay Sach's Disease
Gaucher's Disease:
Defect: Due to deficiency of Cerebroside
degrading enzyme Glucocerebrosidase.
Biochemical Alteration: Abnormal
accumulation of Cerebrosides in the
tissues.
Consequences: Affect normal function of
tissues where it is accumulated.
Tay Sach's Disease:
Defect: Due to deficiency of Ganglioside
degrading enzyme: Hexoseaminidase-A.
Biochemical Alteration: Abnormal
accumulation of Gangliosides in the
tissues.
Consequences: Affect normal function
of tissues.
Similarities and Dissimilarities
Of Cerebrosides and Gangliosides
Similarities Of
Cerebrosides and Gangliosides
Both are Glycolipids containing
Carbohydrate moieties.
Both contain
Sphingosine/Ceramide in their
structures.
Both are richly present in Nervous
tissue.
Dissimilarities Of
Cerebroside and Gangliosides.
S.No
Cerebrosides
Gangliosides
1
Structurally Simple
Structurally complex
Ceramide linked with
Ceramide linked to Glucose,
Glucose or Galactose.
Galactose , NAGalactosamine
,and NANA
2
Occur in White matter Occur in Grey matter of brain
of brain and Myelin
and Ganglions.
Sheaths.
3
Types :
Types :
Glucocerebrosides
GM1,GM2, GM3,GM4
Galactocerebrosides
4
Function : Conducts
Transfer Biogenic Amines
nerve impulse
5
Related Disorder:
Related Disorder:
Gauchers Disease
Tay Sachs Disease
Globosides
Globosides are type of
Glycolipids.
Structurally Ceramide
linked with
Oligosaccharide is
Globosides.
Sulfatides/Sulfolipids
Sulfolipids are compound
Lipids.
Sulfolipids are Ceramide
linked to Sulfated sugar
units/ Oligosaccharides.
Structurally Sulfolipids may also
has Glycerolipids containing
Sulfate groups.
Sulfolipids are component of
nervous tissue.
Lipoproteins
Lipoproteins
Lipoproteins are types of
Compound Lipids
/Conjugated Proteins.
Lipoproteins are
macromolecules formed by
aggregation of :
Lipids (polar and nonpolar )
Proteins( Apoprotein) in
the human body.
Lipoproteins acquire polarity
(Hydrophilic Property)
Lipoprotein serve as
vehicles for transportation
of non polar and polar
Lipids through aqueous
media blood and lymph.
Lipoproteins are
biosynthesized within
the cells of tissues.
By aggregation of various
forms of Lipids and
Apoproteins.
Structure Of Lipoproteins
Structure of Lipoproteins
The non polar /hydrophobic Lipids TAG
and Cholesterol Ester are gathered
centrally to form the core of LipoProtein
particle.
At the periphery of Lipoprotein are
Apoprotein and Amphipathic Lipids
viz Phospholipids and Cholesterol.
The Apoprotein and polar groups
of Amphipathic Lipids impart
hydrophilic property to
Lipoprotein molecules
This helps in transportation of
Lipids
From site of origin to site of
utilization through blood.
Cholesterol Transported as
Lipoprotein Complex (LDL)
Functions Of Lipoproteins
Lipoproteins serve as a vehicle in
transportation of non polar Lipids
From the site of its biosynthesis
to the site of utilization through
aqueous media of blood or lymph.
Types Of Lipoproteins
Depending upon the composition and
other properties following are the types
of Lipoproteins:
Chylomicrons (CM)
Very Low Density Lipoprotein (VLDL)
Low Density Lipoproteins (LDL)
High Density Lipoproteins (HDL)
Free Fatty acid -Albumin
Lipoproteins
Lipoproteins
CHYLOMICRON (CM)
Site Of Synthesis of Chylomicron:
Small Intestine
Percentage of Lipids in CM:
99 % (CM is least dense due to high Lipids)
High concentration of associated Lipid in CM:
Triacylglycerol (Exogenous Origin)
Percentage of Protein in CM:
1%
Associated Apoproteins in CM:
Apo B48, Apo CII and Apo E.
Source Of Lipids in CM :
Exogenous /Dietary origin
Role of Chylomicron (CM) :
CM Transports dietary
exogenous Lipids from Intestine
to Liver through lymph and blood.
VLDL
Site Of Synthesis of VLDL:
Liver (80%) and Small Intestine (20%).
Percentage of Lipids in VLDL : 92%
High concentration of associated Lipid
in VLDL is: Endogenous
Triacylglycerol
Percentage of Protein in VLDL: 8%
Associated Apoproteins in VLDL:
Apo B100, Apo CI, Apo CII and Apo E.
Source Of Lipids to VLDL :
Endogenously
biosynthesized Lipids in
Liver and Intestine.
Role Of VLDL:
VLDL Transports
Endogenous lipids from Liver
to Extra Hepatic tissues.
LDL
Site Of LDL Synthesis:
In Blood circulation from VLDL
Percentage of associated Lipids in LDL:
80%
High concentration of associated Lipid in LDL
is: Cholesterol
Percentage of associated Protein in LDL:
20%
Associated Apoproteins of LDL:
Apo B100, Apo CI, Apo CII and ApoE
Source Of Lipids in LDL:
Endogenously biosynthesized
Lipids in Liver
Role Of LDL:
LDL transports Endogenous
Cholesterol from Liver to extra
hepatic tissues.
HDL
Site of nascent(new) HDL Synthesis:
In Liver
Percentage of associated Lipids in
HDL: 50%
High concentration of associated Lipid
in HDL: Phospholipids
Percentage of associated Protein in
HDL: 50% (HDL is more dense due to high
content of Proteins)
HDL Associated Apoproteins:
Apo A I, Apo A II
Apo C I, Apo C II
Apo D and Apo E
HDL Is Associated
With Enzyme LCAT
Responsible For
Cholesterol
Esterification And Its
Excretion
Role Of HDL :
Transports extra ,non functional
Cholesterol present in blood
circulation to Liver for its
excretion.
HDL has scavenging role with
protective mechanism.
HDL Transports Cholesterol
from
Extrahepatic tissues back to
Liver for its excretion.
HDL Has Role as
Reverse Transport of
Cholesterol
HDL reduces risk of
Atherosclerosis.
HDL clears the body Lipids
and do not allow accumulation
of Lipids in blood.
Thus when the levels of
HDL are within normal
range
Cholesterol associated
with HDL is termed as
Good Cholesterol
Based on Electrophoretic
pattern the Lipoproteins are
termed as:
LDL: Beta Lipoproteins
VLDL: Pre Beta Lipoproteins
HDL: Alpha Lipoproteins
Classification of plasma Lipoproteins
according to their electrophoretic
mobility
(CM)
a-lipoprotein (HDL)
Pre-b-Lipoprotein (VLDL)
b-lipoprotein (LDL)
CM
Types of Lipoprotein
(al contain characteristic amounts TAG, cholesterol, cholesterol esters,
phospholipids and Apoproteins ? NMR Spectroscopy)
Diameter
Major
Class
(nm)
Source and Function
Apoliproteins
Chylomicrons
500
Intestine. Transport of
A, B48,
(CM)
Largest
dietary TAG
C(I,II,III) E
ty
Very low density
43
Liver. Transport of
B100,
si
lipoproteins
endogenously
C(I,II,III) , E
(VLDL)
synthesised TAG
n
g
d
en
Low density
22
Formed in circulation by
B100
lipoproteins
partial breakdown of IDL.
(LDL)
Delivers cholesterol to
I
n
creasi
peripheral tissues
High density
8
Liver. Removes "used"
A, C(I,II,III),
lipoproteins
Smal est
cholesterol from tissues
D, E
(HDL)
and takes it to liver.
Donates apolipoproteins to
CM and VLDL
Lipoprotein
Density Diameter
Protein % Phospholi Triacyl-
class
(g/mL)
(nm)
of dry wt
pids %
glycerols %
of dry wt
HDL
1.063-
5 ? 15
50
29
8
1.21
LDL
1.019 ? 18 ? 28
25
21
4
1.063
IDL
1.006-
25 - 50
18
22
31
1.019
VLDL
0.95 ?
30 - 80
10
18
50
1.006
Chylomicrons
< 0.95
100 - 500
1 - 2
7
84
99
Physical properties and lipid compositions of
Lipoproteins
CM
VLDL
LDL
HDL
Density (g/ml) < 0.94 0.94-1.006 1.006-1.063 1.063-1.210
6000-
Diameter (?)
2000
600
250
70-120
Total lipid
(wt%) *
99
91
80
50
Triacylglycerol 85
55
10
6
Cholesterol
esters
3
18
50
40
Cholesterol
2
7
11
7
Phospholipid
8
20
29
46
Apoprotein % 1 9 20 50
Fatty acid compositions (wt% of the total) in the main lipids of human
Lipoprotein
TriacylglycerolsCholesterol
Esters
Phospholipids
Fatty acid VLDL LDL HDL VLDL LDL HDL VLDL LDL HDL
16:0 27
23
23
12
11
11
34
36
32
18:0 3
3
4
1
1
1
15
14
14
18:1 45
47 44
26
22
22
12
12
12
18:2 16
16
16
52
60 55
20
19
21
20:4
(n-6) 2
5
8
6
7
6
14
13
16
The main properties of the Apoproteins.*
Apoprotein
Molecular weight
Lipoprotein
Function
Lecithin:cholesterol
Apo A1
28,100
HDL
acyltransferase (LCAT)
activation. Main
structural protein.
Apo A2
17,400
HDL
Enhances hepatic lipase
activity
Apo A4
46,000
CHYLOMICRON(CM)
Apo AV(5)
39,000
HDL
Enhances triacylglycerol
uptake
Apo B48
241,000
CHYLOMICRON
Derived from Apo B100 ?
lacks the LDL receptor
Apo B100
512,000
LDL, VLDL
Binds to LDL receptor
Apo C1
7,600
VLDL, CM
Activates LCAT
Apo C2
8,900
VLDL, CM
Activates lipoprotein
lipase
Apo C3
8,700
VLDL, CM
Inhibits lipoprotein
lipase
Apo D
33,000
HDL
Associated with LCAT,
progesterone binding
Apo E
34,000
HDL
At least 3 forms. Binds to
LDL receptor
Linked by disulfide bond
Apo(a)
300,000-800,000
LDL, Lp(a)
to apo B100 and similar
to plasminogen
Apo H, J, L
Poorly defined functions
Apo M
HDL
Transports sphingosine-1
-phosphate
* Roman numerals are sometimes used to designate apoproteins (e.g. Apo AI, AII, AIII, etc)
Disorders Of Lipoproteins
Defect in Lipoprotein
metabolism leads to
Lipoprotein disorders:
Hyperlipoproteinemias
Hypolipoproteinemias
Lipoproteins Atherogenic Particles
MEASUREMENTS:
Apolipoprotein B
Non-HDL-C
VLDL
VLDL
IDL
R
LDL
Small,
dense
TG-rich lipoproteins
LDL
Defect in the receptors
of Lipoproteins on
specific tissues leads to
retention of specific
Lipoproteins in the blood
circulation.
Abnormal high levels of
LDL in blood is due to LDL
receptor defect on
extrahepatocytes bad to
body.
The Cholesterol associated
to high LDL levels is said to
be bad Cholesterol.
This increases the risk of
Atherosclerosis ,Ischemia,
MI and Stroke.
Recently evidenced high
levels of blood HDL are
also bad to body.
This increases the risk of
Atherosclerosis ,Ischemia,
MI and Stroke.
Proteolipids/ Lipophilin
Proteolipids/ Lipophilin
Proteolipids are compound
lipids which have more content
of Proteins than Lipids.
Proteolipid is a
transmembrane domain
protein bound with Lipids.
Occurrence Of Proteolipids
Proteolipids are structural
Lipids
Present on the extracellular
side of the membrane.
Proteolipids are also present
in Myelin Sheath.
Miscellaneous Lipids
Miscel aneous Lipid
Eicosanoids
Eicosanoids are
Classified under
Miscellaneous Lipids.
Eicosanoids is a
generic term
collectively used for
Biologically active 20
carbon(Eicosa) Lipid
like compounds
Name Of Eicosanoids
Eicosanoids is a Generic term for the
20 Carbon related compounds like:
I.
Prostaglandins (PGs)
II. Prostacyclins (PGI2)
III. Thromboxanes (TX)
IV. Leukotrienes (LT)
V.
Lipoxins (LX)
VI. Resolvins
VII. Eoxins
Biosynthesis Of Eicosanoids
Eicosanoids are
derivatives of
Nutritional Essential
Fatty acid/PUFAs.
Eicosanoids are biosynthesized in the
body from PUFAs:
1.
Mostly from Arachidonic
acid/Eicosatetraenoic acid
(PUFA)/Omega 6 Fatty acid
2.
Minorly from Timnodonic
acid/Eicosapentaenoic /Omega 3
Fatty acid
During Eicosanoid
Biosynthesis Mostly
Arachidonic acid is released
by Phospholipids Viz:
Lecithin/PIP3
By Phospholipase A2 activity
Eicosanoids has very
short half life
From seconds to few
minutes
Classification Of Eicosanoids
Prostanoids : Obtained by
Cycloxygenase System :
Prostaglandin
Prostacyclins
Thromboxanes
Leukotrienes and Lipoxins are
obtained by Lipoxygenase System
Prostaglandins are Derivative of
Arachidonic acid
1. Prostaglandins (PGs)
Prostaglandins are type of
Eicosanoids.
PGs also termed as
Prostanoids
Since they are obtained from
parent compound Prostanoic
acid
Biosynthesis Of Prostaglandins
Per day 1 mg of
Prostaglandins are
biosynthesized in human
body.
Prostaglandins are
derived from
Arachidonic acid by
Cycloxygenase system.
Phospholipid Lecithin
releases Arachidonic acid
Arachidonic acid is used for
Prostanoic acid synthesis.
Prostanoic acid then
biosynthesizes Prostaglandin
in human body.
Structure and Types Of PGs
The Prostaglandin structure is
complex and possess:
Cyclopentane ring
Double bond
Carboxylic and Hydroxyl
groups
Prostaglandins
contains a
Cyclopentane ring
with Hydroxyl
groups at C11 and C15
Prostaglandins (PG) are of
following Types:
PG A
PG B
PG C
PG D
PG E
PG F
PG G
PG H
Occurrence/Distribution Of PGs
Occurrence Of PGs
Prostaglandin was first seen in
Prostatic secretion and Semen.
Later it was found that
Prostaglandins are ubiquitous
Present all over in the human
body tissues.
Functions OF Prostaglandins
Prostaglandins serve as Cell
Signaling Agents/Local
Hormones with.
Paracrine in action (act on
sites closely where they are
produced/ neighboring cells).
Autocrine in action that the
sites where they are produced.
Prostaglandins have
diverse functions on
many tissues
Action of one PG is
different in different
tissues.
Sometimes PGs bring
out opposing action in
same tissue.
PGs exert their function
through G-Protein linked
membrane receptors.
1.Role Of PGs In Blood Vessels
PGs Regulate Blood Pressure
PG A and PG E are Vasodilators.
PGs lowers the blood pressure
by:
Increasing blood flow and
Decreasing vascular resistance
in blood vessels.
PGs are used
Therapeutically in treating
Hypertension.
Prostaglandin occur at
Platelets
Inhibits Platelet
Aggregation
and
Thrombus formation
2. PGs Has Role in Uterus At The
Time Of Parturition
PG naturally increases
uterine contraction of
smooth muscles which
induces the delivery of
baby.
PGs can be therapeutically
used as Abortificients during
Medical Termination of
Pregnancies (MTPs).
PGs also arrests postpartum
hemorrhage.
3. Role Of Prostaglandins In Lungs
PGs in Lungs serve as
Bronchodilators and
Bronchoconstrictor of Lungs.
PG E-Bronchodilator
PG F- Bronchoconstrictor
PG E is used in
treatment of
Bronchial Asthma.
4. Role Of Prostaglandin In GIT
Prostaglandin in stomach
increases its motility and
inhibits gastric secretion of
HCL.
PG is used in treatment of
gastric ulcers.
5. Role Of Prostaglandins in Kidneys
PGs in Kidneys increases
GFR and promotes urine
formation and urine out put.
Thus helps in removing
waste out of the body.
PGs Regulate Sleep and Wake
Process
Use of PG D2 promotes
Sleep
6.Effect Of PGs on Metabolism
PGs Decreases Lipolysis (breakdown
of TAG).
PGs increases Glycogenesis.
PGs promotes Steroidogenesis
(Biosynthesis of Steroid hormones)
PGs promotes mobilization of ionic
Calcium from bones.
Role Of PGs
In Immunity And Inflammation
Prostaglandins are produced in
more amounts at the time of :
Fever
Pain
Nausea and Vomiting
Inflammation
To provide immunity to body
Production of PGs
Promote
Fever , Pain , Nausea
Vomiting and Inflammation
PGs are more produced
in inflammatory
disorders like
Rheumatoid Arthritis.
Drugs like NSAIDs Aspirin used
in treating inflammatory
disorders.
Inhibits the Enzyme of
Cycloxygenase system
Which in turn inhibits the
biosynthesis of Prostaglandins.
1.
4.
Regulate Blood
Inhibits Gastic secretion
Pressure
2.
5.
FUNCTIONS OF
Promotes Kidney
Help in Parturition
Prostaglandins
Function
3.
6.
Produces pain,
Bronchodilation
inflammation and Fever
2. Prostacyclins (PGI2)
Prostacyclins (PGI2)
Prostacyclins are type of
Eicosanoids/ Prostanoids.
Principally formed in vascular
endothelium
They are Platelet Aggregation
Inhibition Factors
Biosynthesized by enzyme
Prostacyclin Synthetase.
Roles of Prostacyclins
Prostacyclins are Vasodilators.
Prostacyclins like Prostaglandins
inhibit platelet aggregation.
Prostacyclins prevent
Thrombus/clot formation.
3. Thromboxanes (TX)
Thromboxanes (TX)
Thromboxanes are also termed as
Platelet Aggregating Factor
(PAF).
Thromboxanes are
Prostanoids produced by
Thrombocytes (platelets)
By Enzyme Thromboxy
Synthase.
Structure Of Thromboxanes
Thromboxanes possess
a cyclic Ether in their
structures.
Types Of Thromboxanes
TX A and TX B are types
of Thromboxanes.
TXA2 is more prominent
in human body.
Functions Of Thromboxanes
Thromboxanes are vasoconstrictors.
Thromboxanes enhances platelet
aggregation.
Thromboxanes favors blood clot
formation during blood coagulation.
Thromboxanes and
Prostacyclins are antagonistic
to each other balancing their
activities.
Increased Thromboxane
activity results in Thrombosis.
4. Leukotrienes
Leukotrienes
Leukotrienes are type of
Eicosanoids
Biosynthesized through
Lipoxygenase system in
Leukocytes.
Leukotrienes are a family
of Eicosanoid
Inflammatory
mediators produced
in leukocytes.
Occurrence Of Leukotrienes
Early discovery of
Leukotrienes was in
Leukocytes.
Leukotrienes are also
produced and present in.
Mast cells
Lung
Heart
Spleen
Leukotrienes Structure and Types
Leukotrines are Hydroxy
derivatives possessing conjugated
Trienes .
Types of Leukotrienes:
LTB4, LTC4, LTD4 and LTE4
Effect Of Leukotrienes
Leukotrienes are the component
of Slow Reacting Substances
(SRS-A).
SRS-A are released during
Allergic reactions/Anaphylaxis.
Leukotrienes are
100-1000 times more
potent than
Histamine during
allergic reactions.
LTB4 is a potent
chemotactic agent.
(chemical substance
which mediates
movement of cells).
Leukotrienes by action
are:
Bronchoconstrictors
Vasoconstrictors
LTC4, LTD4 and LTE4 are Slow
- Releasing Substance of
anaphylaxis ( SRS - A ) ,
SRS-A causes fluid leakage
from blood vessels to an
inflamed area.
Overproduction of
Leukotrienes causes
Asthmatic attacks
/Anaphylactic shocks.
An Antiasthmatic
drug Prednisone
inhibits
Leukotriene
biosynthesis.
5.Lipoxins
Lipoxins
Lipoxins are Eicosanoids produced
in Leukocytes of human body.
Lipoxins are:
Vasoactive/Vasodilators
Anti-inflammatory
Immunoregulatory
Chemotactic substances
Omega 6 and Omega 3 Derived
Eicosanoids
Are Opposite in Body Action
Omega 6 Derived Eicosanoids
Prostaglandins:
Promotes Inflammation
Omega 3 Derived Eicosanoids
Resolvins and Eoxins are:
Anti Inflammatory
Anti Allergy
Anti Hypertensive
Anti Cancer
Anti Atherosclerotic
Adverse effects of Eicosanoids
Local pain and irritation
Bronchospasm
Gastrointestinal disturbances:
nausea, vomiting, cramping,
and diarrhea.
Biological Actions of Selected
Eicosanoid Molecules
Generation of arachidonic acid metabolites and their roles in inflammation.
The molecular targets of some anti-inflammatory drugs are indicated by a red X.
COX, cyclooxygenase; HETE, hydroxyeicosatetraenoic acid;
HPETE, hydroperoxyeicosatetraenoic acid.
Amphipathic Lipids
Amphipathic Lipids
Lipids structure
possessing both polar
and non polar groups in
their structure are
amphipathic Lipids.
Amphipathic
/Amphiphillic Lipids are
partially soluble in
water due to their polar
hydrophilic groups
Amphipathic Lipids become
oriented at oil?water
interfaces:
With the polar group
directed in the water phase
The non polar group directed
in oil phase/away from water.
Examples Of
Amphipathic Body Lipids
Phospholipids
Glycolipids
Free Fatty acids
Free Cholesterol
Role Of Amphipathic Lipids
Amphipathic Lipids have following biological
Significances in forming:
Biomembranes:
(Phospholipid bilayer, Glycolipids and
Cholesterol)
Emulsions: (In intestine PL help in Lipids
Digestion)
Micelles:(In intestine help in Lipids
Absorption)
Lipoproteins: for transport of nonpolar Lipids
Liposomes: (Agents for Drug /Gene carrier)
Emulsions
Emulsions are small droplets
of oils miscible in aqueous
phase.
Emulsions are usually formed
by Nonpolar and Amphipathic
Lipids along with Bile Salts in
aqueous phase.
In Human GIT
Emulsions are formed as
small, miscible dietary
Lipid droplets in aqueous
phase of intestinal juice in
intestinal lumen.
Emulsions are
formed during the
process of
Emulsification in
GIT.
Requirements For Emulsification
Emulsifying agents :
Bile salts (Major)
Amphipathic Lipids (Minor)
Mechanical force aids
emulsification.
Emulsifying agents reduces
the surface tension.
Emulsifying agents form a
surface layer of separating
the main bulk of nonpolar
Lipids from aqueous phase.
Emulsions are
stabilized by the
detergent action of
emulsifying agents.
Emulsification Process
Emulsification process takes place in an
aqueous phase of intestinal juice in
intestinal lumen and forms Emulsions.
During Emulsification Hydrophobic or
nonpolar dietary Lipids(TAG) are mixed
with an emulsifying agents:
Bile salts
Lecithin( Amphipathic Lipids)
Mechanical force(provided
by intestinal peristaltic
movement) facilitates the
process of Emulsification.
Types Of Emulsions
I. Oil In Water
II. Water In Oil
Significance Of Emulsions
Emulsions formed in the intestinal
lumen help in the digestion of
dietary Lipids.
The dietary large droplets of
Fat/Oil are transformed to small
,miscible droplets as Emulsions.
Emulsions bring the dietary
Lipids in contact with Lipid
digesting Enzymes present
in aqueous phase of
intestinal juice.
Micelles
Micelles have a disc like shape .
Critical concentration of
Amphipathic Lipids in aqueous
medium form Micelles(~200 nm).
Bile salts help in forming Mixed
Micelles.
Mixed Micelles are
formed after
digestion of various
forms of dietary Lipids.
Aggregation of various
digestive end products of
dietary Lipids covered with a
peripheral layer of Bile salts
form mixed Micelles in the
intestinal lumen.
Mixed Micelles contain
the non polar Lipids in
the interior portions and
polar Bile salts on the
exterior.
Significance Of Mixed Micelles
Mixed Micelles helps in
absorption of dietary
Lipids
From intestinal lumen into
intestinal mucosal cells.
Liposomes
Amphipathic Lipids when exposed
to high frequency sound waves
(Ultra Sonication) in aqueous
medium to agitate particles and form
Liposomes.
Liposomes can be prepared by
disrupting biological membranes by
ultra sonication(>20 KHz )
Structures Of Liposomes
Liposomes are composite structures made of
largely phospholipids and small amounts of
other molecules
Liposomes has spheres of one/ many Lipid
bilayers.
Liposomes contain aqueous regions(polar
phase) and intermittently lipid bilayer (non
polar phase).
Types Of Liposomes
Unilamellar Liposome
Multilamellar Liposome
Structures Of
Liposomes
Role Of Liposomes
Liposomes are vehicles for
administration of drug through
blood, targeted to specific organs.
Topical transdermal delivery of
drugs.
Transfer of Gene into vascular
cells
Water insoluble drugs are
carried in Hydrophobic region
of Liposome.
Water soluble drugs are
carried in Hydrophilic region
of Liposomes.
Biomedical Importance
Of Body Lipids
The Role of various Body Lipids:
Triacylglycerol
Free Fatty acids
Phospholipids
Glycolipids
Lipoproteins
Cholesterol and Cholesterol Ester
Eicosanoids
1.
4.
Builds Membranes
Sources Of Energy, PUFAs
Signal Transmission
,Fat soluble Vitamins
2.
5.
Restores Abundant
FUNCTIONS OF
LUBRICATE
Energy
LIPIDS
Cushioning Effect
3.
6.
Nervous Function
Electrical and Thermal
Lung Surfactant,
Insulators
Emulsifiers
Body Lipids Based On Functions
Energy Storage Lipids
Structural Lipids
Transport Lipids
Metabolic Regulatory Lipids
Thermal and Electrical Insulators
1.Lipids are chief
constituents of food they
serve as a secondary
source of energy (Free
Fatty acid oxidation= 9
Kcal/gm ).
Fatty acids of TAG is a
Source of Energy
Energy-Containing Nutrients (C and H)
H+
ATP Electron
Transport
Chain
CO2
O2
H2O
2.The TAG serve as reserve stores of
Lipid as depot fat in Adiposecytes.
TAG is stored in concentrated,
anhydrous and unlimited form
which supplies energy to muscles for
long term in between meals and
fasting /starvation condition.
3. Dietary Oils and Fat improve the
taste of recipe, increases palatability
and satiety value of foods.
4.TAG protect the internal soft
visceral organs ,give mechanical
support by cushioning effect and
shock absorber.
5.The Lipids (TAG) give shape and
contour to body.
6.Phospholipids, Cholesterol and
Glycolipids are structural
components of various
biomembranes.
7.The Lipids of plasma membranes
imparts integrity, fluidity ,
flexibility and selective
permeability.
8.Dietary Lipids are sources of
essential fatty acids (PUFAs)
which are very essential to bodies
function.
9. Fat soluble Vitamins (A,D,E
and K) are associated with Fatty
foods hence become available from
fatty diet.
10.Amphipathic Lipids serve as
surfactants, detergents and emulsifying
agents.
Dipalmitoyl Phosphatidyl Choline serve as
Lung surfactant and supports good
respiration process.
Phospholipids in GIT helps in forming
Emulsions and Micelles helping in
digestion and absorption of dietary
Lipids.
11.Lipids are poor conductor
of heat and electricity and
serve as Thermal insulators
(Subcutaneous Fat/TAG) to
regulate body temperature.
12.Cholesterol,Glycolipids
and Sphingophospholipids
components of nerve fibers
serve as Electrical
insulators and help in
conduction of nerve
impulse.
12.Lipids Serve as Metabolic Regulators.
Steroidal hormones derived from
Cholesterol.
Prostaglandins serve as Local hormones
regulate various biochemical and
physiological processes of body.
13.Cholesterol ester
(Human body wax)
keep skin lubricated
and water proof.
Good About Body Lipids
Liberate 9 kcal per
Regulates cell
gram of TAG.
function
Major fuel at rest
Maintains
membrane structure
Endurance Exercise Improve nerve
Stores Energy
function
Source of :
Provides flavors and
textures of foods
Essential fatty acids
Helps us feel
Fat-soluble vitamins
satiated
Bad About : Fats and Oils
Excess Fat makes Us Obese
Increases risk for Diabetes Mellitus
Leads to Coronary Artery disease
MI, Stroke
Susceptible to Cancer
855
Disorders OF Lipids
Lipid Storage Disorders
Obesity
Atherosclerosis
Respiratory Distress Syndrome
Fatty Liver
Hyperlipoproteinemias
Hypolipoproteinemias
Necrosis ,Oxidative damage of biomembranes
due to Lipid peroxidation
Lipid Storage Disorders
Inborn Errors Of Lipid Metabolism
Congenital Defects where
deficient of Enzymes
Affects an Abnormal
accumulation of Lipid forms
In cells and tissues affecting
there functionality.
S.No Lipid Storage
Enzyme Defect and
Disorder
Abnormal Accumulation
of
1
Niemann Picks
Sphingomyelinase
Disease
Sphingomyelins
2
Gaucher's Disease
Beta Glucocerebrosidase
Glucocerebrosides
3
Krabbe's Disease
Beta Galactosidase
Galactocerebrosides
4
Tay Sach's Disease
Hexoseaminidase-A
Gangliosides
5
Ferber's Disease
Ceramidase
Ceramides
Common
Lipids Associated Disorders
Obesity
Atherosclerosis
Coronary Heart Disease
Hypertension
Diabetes Mellitus
Disorders Related To TAG
Obesity
TAG is stored as reservoir of energy in
concentrated and anhydrous form.
Adipose tissue is most predominant
in a subcutaneous layer and in
abdominal cavity.
Normal Fat content of adult:
Men 21%
Women 26%
If the Fat content of an adult
body goes above the normal
content the condition is
termed as Obesity.
Obesity has excess fat
depots.
Truncal/central obesity
is a risk factor for heart
attack.
Obesity has abnormal Lipid
metabolism.
Increased Blood Cholesterol and
Lipoproteins.
Obese persons has high
risk of Diabetes mellitus,
Atherosclerosis and CVD.
Questions
Long Answer Questions
Define Lipids (Bloor's
Definition). Classify Lipids
with suitable examples.
Define Fatty acids. Classify
them with different modes
and suitable examples.
What are Compound
lipids? Describe chemistry &
functions of Phospholipids.
What are Sterols? Describe
the structure, dietary
sources, properties &
functions of Cholesterol.
Write Short Notes.
Biomedical importance of body
Lipids
Essential fatty acids (PUFAs) &
their role in the body.
Triacylglycerol/Neutral Fats-
Structure & Function.
Rancidity- Causes & Prevention.
Gycolipids/Cerebrosides/Gangliosi
des
Lipoproteins- Chemistry, types &
functions
Eicosanoids/Prostaglandins
Therapeutic uses of Prostaglandins
Distinguish between Fats & Waxes
Nomenclature & Isomerism of fatty acids
Omega 3 fatty acids and their importance
Amphipathic nature of lipids and their
roles
Distinguish between Fats & Oils
Enumerate biomedical important lipids
with their classes
Properties of Fatty acids.
Simple Lipids with their examples
Enumerate Compound Lipids & one
function of each
Name the Derived lipids & their
functions
Trans Fats
Tests to check the purity of fats &
oils/Characteristic number of Fats
Revision Questions
Define Lipids
Number and Names of Lipid Classes
Define Derived Lipids
Examples of Derived Lipids
Define Fatty acids
What is Delta and Omega end
What is Beta Carbon of a Fatty acid
6 Modes of Classification of Fatty
acids
Fatty acids with one double bond is:-----------
---
Name most predominant Fatty acid of
human body-----
Most easily metabolized fatty acids are :-------
-----,____________- and _____________
Fatty acid with odd and even number carbon
atoms are:
PUFAs are Fatty acids with---------------------
Name PUFAs
Are Nutritionally Essential Fatty acids
and PUFAs same
Name branched Chain and Odd
Number Fatty acids
Name Cyclic and Hydroxy Fatty acids
What are Cis and Trans Fatty acids
Name Omega 3 Fatty acids and 3 Main
Roles
Criteria for Sub classification of Simple
Lipids
Define Simple lipids
Examples/Subtypes of Simple Lipids
What is a Class of Fat/Oil and its
chemical name
Define Waxes
Name body Wax
Differences of Fats and Oils
Occurrence and Role of TAG
Definition Compound Lipids
Types of Compound lipids
Sphingophospholipid Examples
Number and Names Of
Glycerophospholipids
Hormonal role of Phospholipds
Chemical name of Lung
Surfactant
Which Compound Lipid is a Lipid
and Protein?
Biochemistry Department
This post was last modified on 05 April 2022