Download MBBS Biochemistry PPT 52 Lipid Chemistry Lecture Notes

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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