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INDUCTION OF TOPIC
Chief Constituents Of Food
OR
Enumerate Macro Nutrients
Essential Food Nutrients
Carbohydrates
Proteins
Lipids
Body Constituents And Functional Biomolecules
Identify A Food Nutrient
Richly Associated
To Fol owing Food Items
Ghee
Butter
Oil
Curds
Cheese
Milk
Chicken
Fish
Eggs
Any Guesses Of Todays Topic???
LIPIDS
CHEMISTRY AND FUNCTIONS
SYNOPSIS/CONTENTS
? WHAT ARE LIPIDS?
? DEFINITION OF LIPIDS
? CLASSIFICATION OF LIPIDS
? STUDY Of BIOMEDICALLY IMPORTANT LIPIDS wrt:
? STRUCTURE
? DISTRIBUTION
? FUNCTIONS
? PROPERTIES
? RELATED DISORDERS
INTRODUCTION
WHAT ARE LIPIDS?
Pattern To Study Biomolecules
? Name of Biomolecule
? Class and Subclass
? Structural Features
? Sources
? Distribution in Body
? Functional aspects
? Interrelationships
? Derangements and Associated Disorders
Look At Structural Forms Of Lipids
Depicts Its Features
? Lipids are :
? Organic Biomolecules
? Occurs in Plants and Animals
? Food Constituents/Nutrients
? Chemical y Esters - has Ester Bonds(-COO)
? Heterogeneous
? Hydrophobic
? Secondary Source of Energy
? Structural Components of Biomembranes
? Signaling and Nerve Impulse Transduction
Names Of Various Lipids
Associated To Human Body
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)
Important Features Of Lipids
Heterogeneous Nature Of Lipids
Heterogeneity Of Lipids
L
Alter Lipids
I
P
I
Structure
D
S
Functions
Solubility Of Lipids
Solubility Of Lipids
Lipids are relatively Insoluble in
Water/Polar Solvent
Since they have Uncharged/ Non
polar and Hydrophobic groups in
their structures
Lipids are soluble in Fat Solvents
?Lipids are readily soluble in
?Non polar Organic solvents /Fat Solvents
?Acetone
?Alcohol (Hot)
?Benzene
?Chloroform
?Ether
Size And Density Of Lipids
? Lipids are biomolecules relatively :
?Smal er in size
?Less dense
?(Buoyancy- Float in Water)
Complex Lipid structures
are not Bio-Polymers
? Unlike Complex
Carbohydrates
and Proteins
? Lipid structure
contains no
repeatedly linked
Monomeric units
Chemical Nature Of Lipids
Chemical y
? Most Lipids are Esters of
Lipids are Esters
Fatty acids(-COOH) with
Alcohol (-OH)
? Lipids are relatively or
potential y associated with
Fatty acids.
DEFINITION OF LIPIDS
Bloor's Definition Of Lipids
? Lipids are Organic, Heterogeneous Hydrophobic
Biomolecules
? Relatively insoluble in water and soluble in organic
solvents.
? Chemical y Esters of Fatty acids with Alcohol.
? Utilized by body to produce energy ( ATP)
Sources Of Lipids To Human Body
? Exogenous Sources
? Endogenous Sources
? Ingestion Dietary
? Biosynthesis In Liver
? Intestine
Occurrence /Distribution
Of Lipids In Human Body
? Bio Membranes
? Depot Fat
? Nervous System ?
Brain
? Subcutaneous Layer
of Skin
? Padding of Internal
Soft Organs
Biological Functions Of Lipids
Calorific, Membrane Structural, Signaling
S.No Lipid Form
Biochemical Role
1
Triacylglycerol Predominant Lipid form of Diet
Calorific Value
Reservoir of Energy for long term
Insulator and Mechanical Shock
absorber
2
Fatty acids
FAs Stored as TAG
Oxidize to generate ATP
Components of Phospholipids &
Glycolipids
3
Phospholipids Components of Biomembranes
Lung Surfactant
Clotting Mechanism
S.No Lipid Form
Biochemical Role
4
Glycolipids
Components of Biomembranes
Neurons, Myelin Sheaths
5
Cholesterol
Components of Biomembranes
Nerve Impulse conduction
Precursors of Steroids
6
Cholesterol
Transport ,Storage and excretory form
Ester
of Cholesterol
7
Lipoproteins
Vehicles for transportation of various
forms of Lipids through aqueous phase
of blood and lymph
?Lipids of dietary and
Calorific value
?Triacylglycerol
?Fatty acids
Structural Role Of Lipids
Lipids Associated To Biomembranes
1. Phospholipid bilayer
2. Glycosphingolipids
3. Cholesterol
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.
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
i . Compound /Complex Lipids
i i. Derived Lipids
1. Simple Lipids/Neutral Lipids
? Chemical y Simple Lipids are:
? Esters of Fatty acids with an
Alcohol
Sub Classes Of Simple Lipids
Based On Alcohol
? Depending upon the type of Alcohol :
? Simple Lipids are of two sub types:
? Fats/Oils - Triacylglycerol
(Alcohol is Glycerol)
? Waxes
(Alcohol- Cholesterol/ Retinol)
Chemical name of Fat /Oil
IS
Triacylglycerol (TAG)
TAG- Simple Lipid /Neutral Lipid/ FATS or OILS
Uncharged
? Fats/Oils/TAG
? Esters of Fatty acids
with Glycerol
(Trihydric Alcohol)
? Three Fatty acids
linked to a Glycerol
by ester bonds.
? Waxes :
? Waxes are Simple Lipids
? Waxes are chemical y Esters of Fatty acids
with higher complex, monohydric ,Alcohols,
other than Glycerol.
Examples Of Human Body Waxes :
? Cholesterol Ester
(Cholesteryl Palmitate)
? Retinol Ester
(Retinyl Palmitate)
Compound/Complex Lipids
? Compound Lipids is a class of Lipids
? Chemical y composed of Fatty acids
Alcohol and an Additional group.
Depending upon the
Type of Additional group
Types of Compound Lipids are:
Three Main Compound Lipids
1. Phospholipids
2. Glycolipids
3. Lipoproteins
S. Type of
Additional group
No Compound Present
Lipids
1
Phospholipids Phosphoric acid and
Nitrogen Base
2
Glycolipids
Carbohydrate moieties
3
Lipoproteins Apoproteins
Types Of Phospholipids
Based On Alcohol
?Glycerophospholipds
(Contains ?Glycerol)
?Sphingophospholipids
(Contains ?Sphingol)
Types Of Glycolipids/Glycosphingolipids
?Cerebrosides
?Gangliosides
?Globosides
?Sulfatides
?Al Has Alcohol Sphingol/Sphingosine
Lipoproteins
Aggregation of Lipids and Apoproteins
? Chylomicrons
? Very Low Density Lipoprotein (VLDL)
? Low Density Lipoprotein (LDL)
? High Density Lipoprotein (HDL)
Derived Lipids
? Derived Lipids are Hydrolytic products of Simple or
Compound Lipids OR their derivatives.
OR
? Hydrolytic products released from Simple and
Compound Lipids ,who has potency to form them.
Examples of Derived Lipids:
Hydrolytic Products of Simple and Compound Lipids
vFatty Acids
vAlcohols:
?Glycerol
?Sphingol
?Cholesterol
Other Examples Of Derived Lipids
? Lipid like compounds
? Derived from Fatty acids and Sterol/Cholesterol:
? Eicosanoids (Prostaglandins , Leukotrienes
,Thromboxanes)
? Steroidal Hormones: Derived from Cholesterol
? Fat Soluble Vitamins (A,D,E and K)
? 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. Miscel aneous Lipids
D.Miscellaneous Lipids
Substances with Lipid characters
? Carotenoids: b-Carotenoid
? Squalene :
? Vitamin E and K
? Eicosanoids
Types of Lipids
Depending Upon Polarity
? Neutral Lipids: (Non Polar Lipids)
(Contain No polar Groups/Charged groups)
?Triacylglycerol
?Cholesterol Ester (Cholesterol Palmitate)
? Amphipathic/Amphiphil ic Lipids:
(Contain both 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
Types of Lipids
Depending On
Saponification Property
Saponifiable Lipids Undergo Alkaline
Hydrolysis
? A saponifiable lipid is one who undergo Saponification
reaction.
? Saponification is especially an Alkaline hydrolysis of
Ester bond of Fat or an Oil to form Soap.
? In saponification an Ester functional group get
hydrolyzed in presence of Alkaline conditions (NaOH)
producing a free alcohol and fatty acid salt (Soap)
Lipid Based On Saponification
Lipids
Nonsaponifiable
Saponifiable
Steroids
Prostaglandins
Simple
Complex
Sphingolipids
Phosphoglycerides
Waxes
Triglycerides
Study Of Various Classes Of Lipids
Study Of Derived Lipids
Study Of Fatty Acids
FATTY ACIDS( FAs)
Class- Derived Lipids
BASIC COMPONENT
OF LIPID FORMS
What are Fatty Acids?
Fatty Acids Are Derived Lipids
? Fatty acids are of Class Derived Lipids:
?Since Fatty acids are Hydrolytic
products of Simple and Compound
Lipids.
Fatty Acids (FA)
? Fatty Acids (FA) are relatively or
potential y related to various Lipid
structures.
?Simple Lipids
?Compound Lipids
?Derivatives of Lipids
Structure And Chemical Nature
Of Fatty Acids
Chemical Structure Of Fatty Acids
Fatty acid Structures Has
Varied Hydrocarbon Chains
? The Hydrocarbon chain of
each Fatty acid is of varying
chain length (C2 - C26).
Human Body Fatty Acid From C2-C26
S.No Fatty Acid Name Fatty Acid Structure has
Carbon atoms
1
Acetic Acid
C2
2
Propionic Acid
C3
3
Butyric Acid
C4
4
Valeric Acid
C5
5
Palmitic
C16
6
Stearic
C18
7
Oleic
C18
S.No
Fatty Acid Name
Fatty Acid Structure
8
Linoleic Acid
C18
9
Arachidic Acid
C20
10
Arachidonic Acid
C20
11
Behenic acid
C22
12
Lignoceric acid
C24
13
Cerotic acid
C26
? Fatty acid structure have two
ends:
? Carboxylic group(-COOH) at one end (Delta end
denoted as /Alpha end )
? Methyl group (-CH3) at another end (Omega
end denoted as )
Carboxylic Acid Functional Group Of
Fatty Acid
Definition of Fatty acids
Fatty Acids are Defined as:
? Fatty acids are chemical y Organic acids
? With Aliphatic Hydrocarbon chain (of varying
length C2 to C26) with Mono terminal
Carboxylic acid group as functional group.
Different Forms Of
Fatty acids In Body
Free Fatty acid /Unesterified Fatty acid
? Fatty acid who has free Carboxylic group
? Fatty acid not reacted and linked to an
Alcohol by an Ester bond.
Esterified Fatty acid/Bound form of Fatty Acid
?Fatty acid has no free Carboxylic
group
?Fatty acid is linked to an Alcohol
with an Ester bond.
Classification of Fatty acids
Biomedical y Important Fatty Acids
Based On Six Different Modes:
? Classification of FAs Based on Six Modes:
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 (2,4,6,8,16,18,20 etc)
?Odd numbered Carbon Atom Fatty
acids (3,5,7,---)
? Most natural y occurring /human body 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)
? Stearic Acid (C18)
? Oleic Acid (C18) (Most Common)
? Linoleic acid (C18)
? Linolenic Acid (C18)
? Arachidic acid (C20)
? Arachidonic acid (C20)
? Odd Carbon numbered Fatty acids are less related to
human body
? Example of Odd carbon Fatty acid associated to
human body
?Propionic Acid ( 3C)
Fatty acids Based on
Nature and 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)
? Human body have no Enzyme system to introduce
double bond beyond Carbon atom 10 in the
hydrocarbon chain.
? Hence PUFAs are not biosynthesized
in human beings.
? Monounsaturated Fatty Acids(MUFAs):
? MUFAs have one double bond in a fatty acid structure
? Examples of MUFAs :
? Palmitoleic acid (C16:1;9) (7)
? Oleic acid (C18:1;9)(9)
? Erucic acid (C22:1;9)(9)
? Poly Unsaturated Fatty Acids (PUFAs):
? UFAs with two or more double bonds in
the structure are termed as PUFAs.
? Examples Of PUFAS:
? 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 Unsaturated Fatty acids
? Double bonds are:
? Weaker /unstable bonds.
? Get easily cleavable/metabolized
?More the degree of Unsaturation in Fatty
acids.
?More is the unstability of Fatty acids.
? Saturated Fatty acids structures are
Straight.
? Unsaturated Fatty acids structures are
bent (Kink).
? Saturated FAs: with straight structures are
tightly packed together.
? Unsaturated FAs: with bent structures are
not compact and has no tight packing.
? More the degree of unsaturation in
FA/More double bonds in FA
structure
? More is the bent of Fatty acid
structure.
Fatty acids Based on the Nutritional
Requirement
Nutritionally Essential Fatty
acids
?Nutritional y Essential Fatty acids:
?Fatty acids not biosynthesized in
human body and indispensable
through nutrition/diet are termed as
Essential Fatty acids.
?PUFAS are nutritional y essential
Fatty acids.
Examples of Essential Fatty Acids/PUFAs:
?Linoleic
?Linolenic
?Arachidonic acids
?Timnodonic and
?Cervonic
Nutritional y Non Essential Fatty acids
? Nutritional y Non essential Fatty acids:
? Fatty acids which are biosynthesized in the body
and are nutritional y non essential Fatty acids.
? Saturated Fatty acids and MUFAs are non essential
Fatty acids.
Examples Of Non Essential Fatty Acids
? Palmitic
? Stearic
? Oleic acid
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 )
Types Of Fatty acids Based on
Hydrocarbon chain length
? Short Chain Fatty acids (2-6 Hydrocarbon Chain 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 )
? Oleic acid (C18)
? Linoleic acid (C18)
? Linolenic 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)
? Erucic acid/Docosa 13 Enoic (C22)
? Clupanodonic/Docosapentaenoic acid (DPA) (C22)
? Cervonic acid/DocosaHexaenoic (DHA) (C22)
? Lignoceric acid /Tetracosanoic (C24)
? Nervonic /Tetracosaenoic (C24)
? Cerotic acid/Hexacosanoic (C26)
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)
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)
Remember
? Long chain Fatty acids are
also termed as Acyl chains.
vThe systematic names of Saturated Fatty
acids are named by adding suffix `anoic'.
v Example : Palmitic acid- C16/ Hexadecanoic
acid
? The systematic names of Unsaturated Fatty
acids are named by suffix `enoic'.
? Example: Oleic acid- C18/ Octadecaenoic
acid
S.N Common Name Systematic 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 acid Eicosatetraenoic acid
Numbering Of Fatty Acids
? Numbering of Carbon atoms of
Fatty acids is done from :
?Both ends of Fatty acids-
? end/ end
? end
Numbering Of Fatty acid From
Carboxyl/ end ( end)
? From Carboxyl Group end( end ) :
? Carboxylic acid group of Fatty acid is
numbered as C1
? C2 is next adjacent Carbon atom ,
? C3 and so onn..........
? Carbon atom is next to the functional
group ?COOH of a Fatty acid.
? Next to Carbon is , , , and so onn.
? Carbon atoms from Methyl(?CH3)
group /non polar end() of a fatty
acid are numbered as 1,2,3
and so onn.
Nomenclature Of Fatty
acids
? FA Nomenclature is Based On
? Chain length/Total Number of Carbon atoms in a FA.
? Count Number of Carbon atoms in FA
? Number and Position of Double bonds
? Position of double bond from Carboxyl/Delta end
? Position of double bond from Methyl/Omega
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 )
22:5 CisD7,10,13,16,19 Docosapentaenoic acid (3 )
Important Properties Of Fatty Acids
Properties Of Fatty Acids
? Physical Properties
? Chemical Reactions
Physical Properties Of Fatty Acids
1. Solubility
2. Melting Point
Solubility Of Fatty Acids Depends
Upon
Factors Responsible For Solubility Of
Fatty Acids
1. Hydrocarbon chain length
2. Degree of Unsaturation- Number of Double Bonds
3. Hydrophobicity/Polarity of Fatty acids
4. Polarity of Solvents
? Smal hydrocarbon chain length are less
hydrophobic and more soluble
? Long Chain FA and VLCFA more hydrophobic are
very less soluble
? Solubility of Fatty acids decreases with increase in
Fatty acid hydrocarbon chain length.
? Double bonds increases solubility
Melting Point of Fatty Acids
Factors Responsible For
Melting Points Of Fatty Acids
1. Hydrocarbon chain length
2. Nature of Bonds
3. Degree of Unsaturation/Number of double bonds
Fatty Acids With
Decreased Melting Points
? Short and Unsaturated Fatty
acids has low melting point
? More degree of unsaturation low
is melting point 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
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
Fatty Acids With
Increased Melting Points
? Long and Saturated Fatty acids are
has high melting point.
? Less degree of Unsaturation more is
melting point of Fatty acids
? Thus melting point of Fatty acids(FAs):
?Increases with increase in chain
length of FAs.
?Decreases with decrease in chain
length of FAs.
?Increases with low unsaturation of
FAs
?Decreases with more unsaturation of
Fatty acids
Structures and Melting Points of Saturated Fatty Acids
Chemical Reactions Of Fatty Acids
Types Of Chemical Reactions
Of Fatty acids
Reactions due to
Carboxyl group of Fatty acids:
? Esterification/Esterified forms of Lipids
? Saponification/Soap Formation
Reactions Associated to
Double bonds of Fatty acids:
? Halogenation/Addition of Halogens around double
bond
? Hydrogenation/Transform to UFAs to SFAs
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.
Hydrogenation Of Fatty acids
Alters Geometric Isomerism Of
Unsaturated Fatty acids
Transforms Natural Cis Form to Trans Form
Increases Shelf life of PUFAs
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 All ?Cis forms are good for health and no
risk of Atherosclerosis and CVD.
? Al Cis form of fatty acids are unstable and
easily metabolizable.
? More content of Trans Fatty acids are found
in processed/Refined 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 increases risk of
:
?Atherosclerosis
?Cardio Vascular disorders:
?Ischemia
?Myocardial Infarction
?Stroke(Brain attack)
Message
Learnt, Understood And To Be Implemented
For Good Fatty acid metabolism and Significant Health
? Eat natural Cis forms of Fatty acids
? Avoid Hydrogenated Trans Fatty
acids
? Eat home made food
? Avoid Processed/Junk Foods
PUFAs And Omega Fatty Acids
Types Of Omega Fatty acids
?In Nutrition and Clinical
practice
?3 Fatty acids
?6 Fatty acids
?7 Fatty acids
?9 Fatty acids
Omega Fatty Acids
Omega 3 Fas
Omega 6 Fas
Omega 7 Fas
Omega 9 Fas
PUFAs
PUFAs
MUFAs
MUFAs
Linolenic
Linoleic
Palmitoleic Oleic ?
C18-(ODTA)
C18- (ODDA) C16-(HDA) C18(ODA)
Timnodonic
Erucic ?
C20-(EPA)
Arachidonic
C22(DA)
Cervonic
C20-(ETA)
Nervonic
C22-(DHA)
C24-(TA)
Clupanodonic
C22-(DPA)
Examples of 3 Fatty acids
? Linolenic (18:3;9,12,15) (3)
? Timnodonic/Ecosapentaenoic Acid /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)
Rich sources of dietary Omega and nutritional
essential PUFAS are:
?Vegetable Oils
?Green Leaves, Algae
?Fish and Fish oils
?Flax Seeds
Sources,Distribution,Composition Of
Fatty Acids In Human Body
Sources Of Fatty Acids To Human Body
? Exogenous Sources- Dietary Food Items
? Endogenous Biosynthesis- From Free Excess
Glucose in Liver
Forms of Dietary Fatty Acids To Be Ingested
Natural Forms Of Fatty Acids
? Fatty acids in nature mostly presently in
? Esterified form of FAs? (TAG,PL,CE)
? Even Numbered Carbon
? Unsaturated- PUFAs/Omega 3 and 6
? Cis forms
Contents Of Fatty acids Sources Of Oils
Highest Content of MUFA Olive Oil , Mustard Oil
Highest content of PUFA Safflower, Sunflower,
Flax seed Oil
Highest content of SFA
Coconut Oil
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 (85%)
Soya /Safflower Oil
Butter
Ground nut /
Almond Oil
Pea nut Oil
Animal Fat
Almond Oil
Rice Bran
Sesame Oil
Walnuts Oil
Beef Fat (Tal ow Fat) 50%
Corn Oil
Lard (Pork Fat) 40%
Marine Fish
Carbons
Double bonds
Abbreviation
Source
Fatty Acids
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
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 most abundant Fatty acids
present in human Lipids are:
?Oleic acid (50%)
?Palmitic acid(35%)
Ideal 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.
Transportation Of Fatty Acids In
Human Body
? Bound form /Esterified
Forms Of Fatty acids are
Transported through
various Lipoproteins.
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 Esters/Esterifed form of Fatty
acids exist as:
? Triacylglycerol
? Cholesteryl esters
? Phospholipids
? Unesterified/Free Fatty acids (FFA)
are very less amount in body.
? Long Chain FFA are transported in
the blood circulation in association
with Albumin.
Functions Of Fatty Acids
1. Secondary Source Of Energy
2. Components Of Biomembranes
3. PUFA (Arachidonic Acid) Precursor for Eicosanoid
Biosynthesis
4. Esterification of Cholesterol and its Excretion
5. PUFAs build and protect Brain and Heart
6. PUFAs prevents early ageing, prolongs Clotting
time.
? PUFAs of membrane play role
in:(Less compact)
?Membrane fluidity
?Selective permeability
Functions Of
PUFAS /Omega 3, and 6 FAs
? Components of cel biomembranes
? More associated to Human brain and Heart
? Involve in Growth ,development and
functioning of Brain
? Omega Fatty acids Reduces risk of Heart disease:
?Reduces Platelet aggregation by stimulating
Prostaglandins and Prostacyclin's .
?Reduces blood clotting and Thrombus
formation by Lowering the production of
Thromboxane .
? Omega 3 Fatty acids have pleiotropic effects
(more than on effect):
?Cardio protective effect
? Lowers Blood pressure
? Anti-Inflammatory
? Anti-Atherogenic
? Anti-Thrombotic
? PUFAs Lowers Risk Of Atherosclerosis
? Since double bonds of PUFAs are unstable and
easily cleavable.
? PUFAs get easily metabolized and do not get
accumulated in the blood arteries and capillaries.
? Thus PUFAs have low risk of Atherosclerosis and
Cardio vascular disorders.
? Fish (rich in Omega 3 Fatty acids) Eaters has
Healthy Brain and Heart
? Brain development with an efficient
nervous function.
? Protected from Heart attacks.
? Deficiency of Essential Fatty acids :
? Affects every cel ,organ and system
?Growth retardation
?Problems with reproduction
?Skin lesions
?Kidney and Liver disorders
?Brain disorders/Behavioral disorders.
Deficiency Of PUFAs/ Omega 3,6
Fatty acids
? Deficit of omega fatty acids affect the normal
growth ,development and functioning of brain.
? Persons may suffer from mental il ness like:
?Depression
?Attention deficit
?Dementia=Alzheimer's Disease
? Deficiency of Omega 3 Fatty acids :
?Alters the cell membrane structure.
?Increases the risk of
? Heart attack
? Cancer
? Rheumatoid Arthritis
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
? Acanthosis and Hyperkeratosis
? Deficiency of PUFAs lower:
?Oxidative Phosphorylation-ATP generation
?Fibrinolytic Activities
Fatty Acids At Glance
Name of Biomolecule Fatty acids
Class
Derived Lipids
Structural Features
Organic acids ,Hydrocarbon Chain (C2-
26) Terminal Mono Carboxylic Acid
Sources of FAs to
From Exogenous and Endogenous
body
Distribution in Body FAs mostly in esterified form,
Associated with Simple and
Compound Lipids. Distributed in all
tissues.
Functional aspects
Energy, Biomembrane components
Interrelationships
Fatty acids associated to other form
of Simple and Compound Lipids
Study Of Derived Lipids
Alcohols
Alcohols Involved In
Lipid Structures
3 Alcohols Involved In
Various Forms Of 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 is a
Derived Lipid
Obtained from Hydrolysis of
Simple and Compound Lipids
Glycerol/ Glycerin
? Glycerol [C3 ]is a POLYOL
? Glycerol is chemically Trihydric
Alcohol (3 ?OH groups)
? Glycerol has potency to interact
with 3 same or different Fatty
acids .
vGlycerol is a backbone of
Glycerol based Lipids viz:
v Triacylglycerol
v Glycerophospholipids
Glycerol Sources To Human Body
Endogenous and Exogenous Sources
Glycerol
Glucose
Source Of Glycerol To Human
body
? Glucose is responsible for biosynthesis of Glycerol
in human body
? Glucose transforms to Glyceraldehyde,
? Glyceraldehyde on reduction forms Glycerol.
? Glycerol formed is then used for Biosynthesis
of Glycerol based Lipids.
? Glycerol released from hydrolysis of Glycerol
based Lipids is transformed to Glucose.
SPHINGOSINE/SPHINGOL
? Sphingosine is a derived
Lipid.
? Obtained from Hydrolysis of
Sphingolipids
? Sphingosine is a C18, complex Dihydric,
Amino alcohol.
? Sphingosine is biosynthesized in human
body using amino acid Serine.
? Serine provides NH2 group of
Sphingosine.
? Sphingosine forms Sphingolipids
/Compound Lipids with Alcohol
Sphingol
? Examples of Sphingolipids:
?Sphingophospholipids
?Sphingoglycolipids
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 Sphingoglycolipids.
Sphingosine Based Lipids
Sterols
Common Sterol And Steroids
Vitamin D3
Cholesterol
(cholecalciferol)
(a sterol)
Testosterone
Stigmasterol
(a steroid
(a phytosterol)
hormone)
? Sterols are chemical y
complex, organic monohydric
Alcohols.
? Sterols has cyclic ring
structures
?Sterols have a parent ring
?Cyclo Pentano Perhydro
Phenantherene (CPPP)
nucleus.
Examples Of Sterols
? Cholesterol (Animal Sterol)
? 7 Dehydrocholesterol( Provitamin D)
? Coprosterol (Excretory form Cholesterol)
? Ergosterol (Plant Sterol)
? Sitosterol (Plant Sterol)
Cholesterol
Most abundant Sterol of Human body
Cholesterol
? Cholesterol is an Animal Sterol .
? Cholesterol means Solid Alcohol as it
was first obtained from gal stones of
bile.
? Cholesterol is excreted via bile hence
richly composed in bile ,Gal stones.
Cholesterol
Is A Derived Lipid
? Cholesterol is classified as
Derived Lipid.
? It is derived from hydrolysis of
Cholesterol Ester (Human Body
Wax).
Chemical Structures Of
Cholesterol and Cholesterol Ester
Pentahydrophenantrene
(Sterane)
Structure Of Cholesterol
? Cholesterol is complex, cyclic,
unsaturated, monohydric Alcohol.
? Molecular formula is C27H45OH
? 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.
? The Structure of Cholesterol Possess:
1. Hydroxyl group (-OH) at C3.
2. Double bond between C5 and C6.
3. 5 Methyl (-CH3) groups.
4. 8 Carbon side chain linked to C17 of
the structure.
Forms Of Cholesterol In Human Body
? Cholesterol exists in two forms:
?Free Cholesterol - 30%
(Amphipathic form)
?Cholesterol Ester - 70%
(Non polar form)
Properties Of Cholesterol
? Cholesterol is white or pale yel owish,
crystal ine ,odorless compound.
? Insoluble in water and soluble in organic
solvents like Ether and Chloroform.
Crystals of Cholesterol Rhombic plates
with Notched edges.
? Qualitative Tests For 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 wel fed condition from
Excess Glucose
Dietary Sources Of Cholesterol
?Cholesterol is exclusively
present in animal foods.
? The dietary rich sources of Cholesterol
animal origin foods like:
?Egg Yolk
?Meat
?Milk
?Butter
?Ghee
?Cream
?Remember Cholesterol
is absent in plant origin
food items.
Endogenous Source Of Cholesterol
? Cholesterol Biosynthesized in
human body from Free Excess
Glucose in Liver.
Transportation Of Cholesterol
?Cholesterol in blood is
transported by Lipoproteins:
? Chylomicrons ( Dietary origin)
? LDL (From Hepatocytes to Extra hepatocytes)
? HDL (From Extra hepatocytes to Hepatocytes)
Occurrence and Distribution Of
Cholesterol in the Body
?70 % of Cholesterol associated
with cel ular components
?30 % of Cholesterol is in the
Blood.
? Cholesterol is richly present in Nervous
tissue Brain.
? Other organs containing Cholesterol are:
?Liver
?Adrenal Cortex
?Gonads
?Intestinal Mucosal cel s
?Skin
Functions Of Cholesterol
Depends Upon
Quality and Quantity
? Cholesterol is constituent of biomembranes
of cel
? It give structure, shape and fluidity to them.
Effects on Membrane without Cholesterol
In Cold Environment In Hot Environment
Rigid/ Not Flexible
Too Flexible
Not Fluid
Very Fluid
May Get damage
Not hold Shape
? Cholesterol richly present in
nervous tissue and covers
Myelin sheaths.
? Cholesterol help in nerve
impulse conduction.
? Cholesterol helps in nerve
impulse transmission since:
?It has high dielectric constant.
?It is a poor conductor of heat
and electricity.
Cholesterol Serves Precursor for
Biosynthesis Of Many Steroids
Derivatives of Cholesterol
? Steroids are derivatives of Sterols.
? Chemical Compounds obtained
from Cholesterol are termed as
Steroidal compounds.
? Derivatives of Cholesterol
? 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 level 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.
Conditions Of Hypercholesterolemia
?Diabetes mellitus
?Obstructive Jaundice
?Nephrotic Syndrome
?Hypothyroidism
? 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
Triacylglycerols/Triglycerides
? Chemical name of Fat/Oil is Triacylglycerol
(TAG).
? TAG is a Simple, Glycerol based
,Neutral Lipid.
Chemical Structures Of
Triacylglycerol (TAG)
Triacylglycerol/Fats/Oils
? TAG/Fats/Oils are
? Chemically Esters of
? Three Fatty acids ( Same or Different)
? with one Glycerol (Trihydric Alcohol).
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
?TAG is Neutral or Non
polar lipid.
?Since TAG structure has
no charged/polar groups
in its structure.
Types Of Triacylglycerol
Based On Nature Of Fatty Acid
?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
? 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
Olive Oil Rich In Simple TAG
? Olive oil contains mostly TAG as Triolein, which has
three Oleic acids.
Sources OF Triacylglycerol
To
Human Body
?Exogenesis source of TAG :
?Dietary Fats/Oils
?Endogenous source of TAG :
?Liver Lipogenesis in wel 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.
TAG Major Lipid Form Of Human Body
?Predominant Lipid ingested
in Human diet is TAG 98%.
?Abundant Lipid of human
body Lipid is TAG 95 %.
Transportation Of TAG in
blood is By Lipoproteins
?Chylomicrons :
?Transports
exogenous dietary
TAG
?VLDL:
? Transports
endogenous TAG
Biomedical Importance Of TAG
S.No Distribution/Location Of TAG in Role of TAG
Human Body
1
Predominant Dietary Form of
Dietary and Calorific
Lipid Ingested in GIT
Value- Secondary
Source of Energy
2
Adiposecytes/Depot Fat-
Reservoir of Energy
Exclusively TAG
3
Subcutaneous layer /Below Skin Insuating Effect,
Regulates Body
Temperature
4
Fat Pad around Internal Soft
Mechanical Shock
Visceral Organs
absorbers
1.TAG Serves As Source Of Energy
? TAG has high calorific value
(9Kcal/gram) more than
Carbohydrates (4 Kcal/gram ).
2.TAG Reservoir Of Energy
Storage form of Lipid in
human body is TAG.
Triacylglycerols In Its Structure
Links and Stores Fatty acids
? 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 .
Criteria's For TAG To Be Chosen As
Reservoir of Energy
? TAG is highly reduced and
anhydrous form.
? Hence chosen as energy
reserve of the body.
? 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)
3.Store House Of TAG
is High
In Comparison To
Glycogen Stores
? 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)
? TAG When excess serves as
an energy reservoir stored in
Adipocytes as :
?Anhydrous form
?Concentrated
?Unlimited amount
?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.
? 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 skin smooth and
supple.
Remember TAG is
not associated to
biomembranes.
? MAG and DAG are derived Lipids.
? Monoacylglycerol and
Diacylglycerol are hydrolytic
products of Triacylglycerol.
? These are produced during TAG
metabolism in the body.
?Monoacylglycerol (MAG)
/(Monoglycerides): A Glycerol esterified
with one fatty acid.
?Diacylglycerol (DAG) (Diglycerides):
?A Glycerol esterified with two fatty acids.
Healthy TAG In Human Body
? Ingesting Natural Mixed Form ? PUFAs and Short chain
FAs
? Avoiding Trans Fats
? Balanced/Moderate ingestion
? No excess or deficient TAG stores
? Normal serum TAG levels < 150 mg%
Disorders Associated To TAG
Bad About : TAG/ Fats and Oils
?Excess Fat leads to Obesity
?Increases risk for Diabetes Mel itus
?Leads to Coronary Artery disease
?MI, Stroke
? Susceptible to Cancer
347
Disorders Related To TAG
? 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.
vObese persons has high risk of
vDiabetes mel itus
vAtherosclerosis and CVD
? Consequently lead to
Metabolic Syndrome
Prevent Obesity
Properties Of Triacylglycerol
Lipid Peroxidation
(autoxidation)
Lipid Peroxidation
Is a source of Higher Free Radicals
? During Oxygen metabolism in body.
? Oxygen derived free radicals (RO.,OH.,ROO.)
with unpaired electrons are released.
? These Reactive Oxygen Species (ROS) , Free
radicals interact and oxidize double bonds of
PUFAs leads to chain reactions of lipid
peroxidation.
? Steps of Lipid peroxidation
reaction:
?Initiation
?Propagation
?Termination
? PUFAs are more prone for
peroxidation.
? Lipid peroxidation Provide
continuous Free radicals.
? Thus has potential y
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 cel s & 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.
? Natural y occurring antioxidants are :
?Vitamin E
?Vitamin C
?Beta Carotene
? Body Enzymes as Antioxidants:
?Catalase
?Glutathione Peroxidase
?Superoxide Dismutase
? Other Substances as Antioxidants:
?Urate
?Bilirubin
? Food Additives as Antioxidants:
?Alpha Naphtol
?Gallic Acid
?Butylated Hydroxy Anisole (BHA)
?Butylated Hydroxy Toluene (BHT)
? Preventive Antioxidants:
? Reduces rate of Chain initiation of
Lipid peroxidation
?Catalase
?Peroxidase
?EDTA
?DTPA
? Chain Breaking Antioxidants:
? Interferes the chain propagation
of Lipid peroxidation.
?Vitamin E
?Urate
Rancidity Of Fats/Oils
Rancidity
? Rancidity is a physico chemical
phenomenon
? Which deteriorates Fats and Oils
? Resulting in an unpleasant taste
,odor and color of Fat/Oil
(Rancid Fat/oil)
?Rancid Fat is inedible
Factors Causing Rancidity
? 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.
PUFAs are more prone to
Rancidity
Since Double bonds are
more susceptible to Lipid
peroxidation
Causes Of Rancidity
? Fats and Oils get Rancid on Ageing.
? Various Factors aggravates rancidity of Oils
and Fats:
? Improper handling by an exposure to:
?Light
?Air (Oxygen)
?Moisture
?Microbes
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 cel ular 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
a Fat rancid.
Ketonic Rancidity
? It is due to the contamination with
certain Fungi such as Asperigil us 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 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 fungalcontamination
q Addition of Antioxidants
Prevention Of Rancidity
? Rancidity can be prevented by
proper handling of oils
?By keeping fats or oils in wel
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
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 natural y associated
antioxidants .
? Rancidity of Fats and Oils is
prevented by adding Antioxidants.
? Thus addition of Antioxidants
increases shelf life of
commercial y synthesized Fats
and Oils.
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 associated with it.
Others Properties Of TAG
Depends On Nature Of Fatty Acids
Chain Length Of Fatty acids
Of TAG affects Melting Point
? "Hardness" of the Fat/TAG depends on chain
length.
? < 10 carbons in Fatty Acid = liquid
? >20 carbons in Fatty Acid = solid
Acetic Acid (2 C)
Vinegar
Liquid
Stearic Acid (18 C)
Beef Tallow
Solid
Arachidic Acid (20 C) Butter
Solid
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.
? 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.
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 cal ed "Hardening of Oils"
? Hydrogenation converts PUFAs with cis form
to trans form.
? Margarine
? Vanaspati Dalda Crisco, Spry, etc.
Advantages and Disadvantages Of
Hydrogenation Of Fat /Fatty acids
Advantages Of Fat Hydrogenation
? Hydrogenation transforms unstable
,unsaturated , liquid TAGs:
?To stable, saturated, solid TAGs
?Reduces risk of Rancidity
?Increases shelf life and business.
?Example : Vanaspati Dalda ,Margarine.
Disadvantages Of Hydrogenation Of
Fat/Fatty acids
Trans Fats increases the risk of
Atherosclerosis and CVD.
? Hydrogenated trans Fats are
more stable.
? Body has no enzyme system to
oxidize and metabolize trans
fatty acids.
?Remember
Hydrogenated Fats
are Bad for Health.
? Summary Of Fat Hydrogenation:
? Hydrogen atoms are added to unsaturated
Fatty acids
?Make liquid oils more solid and more
saturated.
?Create trans fatty acids.
?Reduces peroxidation of Fatty acids.
?Resists rancidity
?Reduces metabolism
?Increases retention
?Increase risk of cardiovascular disease.
?Note
?Try eat more natural TAGs.
?Avoid Processed Fats.
Tests To Check Purity
Of
Fat and Oil
? Several laboratory tests are
employed to:
?Check the purity
?Degree of adulteration
?Biological value of Fat and
Oils.
Tests to Check Purity of Oils and Fats
Tests To Check Purity of Oils Importance/Significance
Iodine Number
Index of unsaturation and
content of unsaturated fatty
acids
Saponification Number
To know Chain Lengths of
Fatty acids
Acid Number
Checks purity of Refined oils
Reichert Meissl (RM)
Useful in testing the purity of
Number
butter
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 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
mil igram/number of KOH molecules
required to hydrolyze and saponify one
gram of Fat/Oil.
? Saponification number gives the
idea of molecular size/chain
length of Fatty acids present in 1
gram of Fat.
? 1 gram of Fat/oil with long chain
fatty acids has lower
saponification number.
? 1 gram of oil containing short chain
fatty acids has high Saponification
number.
? 1 gram Oil with short chain fatty
acids has higher saponification
number.
? Since it has more COOH groups for
KOH reaction.
? 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.
Oils
Saponification Number
Coconut Oil
250-260
Butter
230-250
Jojoba Oil
69- 80
Olive Oil
135-142
Acid Number
? Acid number is mil igram 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 distil ed
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.
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 content
Oils have high antioxidant content
and get easily Rancid
and do not get easily Rancid
Fats are more stable
Oils are less stable
Fats are less metabolizable in body. Oils are readily metabolizable 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
? 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
? Compound Lipids
? Components:
? Alcohol- Glycerol/Sphingol
? Fatty Acids- PUFAs and SFAs
? Additional Group- Phosphoric acid and Nitrogenous
/Non Nitrogenous moiety
? Nature- Amphipathic
? Phospholipids (PL) Chemical y Possess:
?Fatty acids esterified to Alcohol and
?Phosphoric acid attached with
Nitrogenous /non nitrogenous base.
Types Of
Phospholipds
Based upon Alcohol
Present in Phospholipid structure
? Two Types of Phospholipids are :
?Glycerophospholipids:
Glycerol containing Phospholipids
?Sphingophospholipids:
Sphingosine/ Sphingol containing
Phospholipids.
Glycerophospholipids/
Glycerophosphatides
Names & Structures
OF
7 Glycerophospholipids
Simplest Glycerophospholipid
PHOSPHATIDIC ACID
? Depending upon 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 (Cephalin)
5. Phosphatidyl Inositol/ Lipositol
6. Phospatidal Ethanolamine/ Plasmalogen
7. DiPhosphatidyl Glycerol /Cardiolipin
Phosphatidic Acid
? Phosphatidic acid is a simplest
Glycerophospholipid.
? Phosphatidic acid has Glycerol esterified
with two Fatty acids at C1 and C2 .
? C3 is esterified with Phosphoric acid.
? Phosphatidic acid serve as a
precursor for biosynthesis of
other Glycerophospholipids
? Either by linking of
?Nitrogenous or
?Non nitrogenous base
Phosphatidyl Choline/Lecithin
? Phosphatidyl Choline (Lecithin) is
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.
Cephalins
?Type of Glycerophospholipids
?Nitrogen base is Ethanolamine
or Serine.
?Phosphatidylethanolamine and
Phosphatidylserine are
Cephalins.
Phosphatidyl Ethanolamine
Phosphatidyl Serine
? An Amino acid Serine
linked to Phosphatidic acid
forms Phosphatidyl Serine.
Phosphatidyl Inositol/ Lipositol
Phosphatidyl Inositol Tri Phosphate
(PIP3)
? Inositol/Myo Inositol a Polyol
derived from Glucose
? 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
Di Phosphatidyl Glycerol
? 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
? Sphingomyelin is an example
of Sphingophospholipid.
? Sphingophospholipid is
Sphingosine based Lipid
? Which has Sphingosine linked
with Fatty acid-Phosphate
and Choline.
? 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/
Amphiphil ic 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
Exogenous And Endogenous Sources
Of Phospholipids
Occurrence And Distribution Of
Phospholipids
? Various types of Phospholipids
Associated to al over body cel s.
? Most predominantly associated to
Biomembranes
? Myelin Sheath
? Alveoli in Lungs
Functions Of Phospholipids (PL)
1. Biomembrane Components
2. Lung Surfactant
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
Lecithin Is Most Functional Phospholipid
1. Phospholipids Components Of
Biomembranes
Phospholipid Bilayer of
Plasma membrane
Cholesterol intercalates among Phospholipids.
Cholesterol fills in the spaces left by the kinks of
PUFAs .
Cholesterol stiffens the bilayer and makes membrane
less fluid and less permeable.
? Role Of Lecithin
? The Glycerophospholipid Lecithin is
the major structural components of
biomembranes.
? An Amphipathic phospholipid bilayer
has polar head groups of PL directed
outwards.
? Membrane Phospholipid bilayer
,constituent of cel 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/cel
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 cel s, 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.
2.Phospholipid As Lung Surfactant
? DiPalmitoyl Phosphatidyl Choline serve
as an Lung surfactant.
? It Lowers surface tension and keeps
Alveoli of lungs blown. (prevent
adherence of alveoli)
? Enables effective exchange of gases
(Oxygen) in Lungs.
? After expiration of air the
alveoli gets deflated.
? The lung surfactant reduces
the surface tension and al ow
the alveolar wal s to
reinflate.
?Phospholipid as Lung
surfactant
?Prevent body to suffer
from Respiratory Distress
Syndrome (RDS).
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.Phospholipid Lecithin
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
Cel death).
10.Role Of Phospholipids In
Hormonal Action
Mediates Cel Signal Transduction
? Role Of Phosphatidylinositol
? Phosphatidyl Inositol
Triphosphate (PIP3) is a
constituent of cel membrane
? It mediate hormone action /cel
signal transduction and maintain
intracel ular 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 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 col apse.
?Signs And Symptoms Of
RDS
?Low ATP production
?Weakness ,Lethargy
?Low Cellular Functions
?Poor Coordination
Lecithin/Sphingomyelin (L/S) Ratio
of Amniotic Fluid
Assessment Of Fetal Lung Maturity
And
Diagnostic Criteria For RDS
? Lecithin /Sphingomyelin (L/S)
ratio of amniotic fluid, col ected
by Amniocentesis 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 ful term L/S ratio is > 2/>5
? In pre term infants L/S ratio
is 1.5 or < 1 results to suffer
from RDS.
OTHER RDS Sufferers
Individual with Lung Damage and
Dysfunctions
? Old aged Persons
? Smokers
? Severely Infected Lungs
? Lungs toxicated and damaged by chemicals
? Old age persons and Adults with
Lung damage
(Due to Smoking/ Infections)
? Who unable to biosynthesize the
lung surfactant may also exhibit
RDS.
Prevent And Manage RDS
? Pregnant Women Diet for biosynthesis of L and S
? Pregnant Women Activities and Positions
? Prevent Damaging Environment Exposures
Membrane Related Disorders
Due To Defective Phospholipds
Multiple Sclerosis Due to Defect In
Sphingomyelins and Myelin Sheaths
Defect In Sphingomyelins
May Affect
Nerve Impulse Conduction
Membrane Carbs,Lipids and Proteins
Structural y Important For Functional Role
? Deranged Cellular Environment
? Cell membrane Damage
? Tissue Necrosis
? Cell Death
Mitochondrial Electron Transport Chain
Defects
Due to Phospholipid Deficits
Fatty Liver
Due to Phospholipid Defects.
Glycolipids
OR
Glycosphingolipids
What are Glycolipids?
? Glycolipids are type of compound
Lipids.
? Chemical y Esters of Fatty acids with
Alcohol and contain additional group
as Carbohydrate moieties
Types Of Glycosphingolipids
Based Upon
? Alcohol
? Fatty acid
? Number and Type of Carbohydrate
moieties and there derivatives
linked to a Ceramide
Types OF Glycolipids
Based on Alcohol
1. Glycoglycerolipids
( More In Plants)
Glycerol as Alcohol
2. Glycosphingolipids
(Predominant in Animals and Human)
Sphingosine as Alcohol
Glycosphingolipids
Predominant Animal Glycolipids
? Ceramide linked with one or
more sugar residues /there
derivatives
Human Glycosphingolipids
Al has Ceramide in Their Str
1) Cerebrosides
2) Gangliosides
3) Globosides
Cerebrosides
Simplest GlycoSphingolipids
Monoglycosylceramide
Cerebrosides
? Cerebrosides are type of
Glycosphingolipids
? Ceramide linked with one
sugar residue
Types of Cerebrosides
? Depending upon Carbohydrate moiety
Types of Cerebrosides are:
?Glucocerebrosides
(Occur In Extra neural/Other tissues)
?Galactocerebrosides
(Present In Neural)
Structures Of Cerebrosides
Galactocerebroside
Cerebrosides
Fatty Acid Composed In
Kerasin
Lignoceric acid (C24)
SFA
Cerebron
Cerebronic acid (C24)
Hydroxy SFA
Types of Cerebrosides based on Fatty acids:
Nervon
Nervonic acid (C24)
MUFA
Oxynervon
Oxynervonic acid (C24)
MUFA
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
? 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.
Structure Of Gangliosides
? GM3 is more common and
simplest Ganglioside.
? GM3 has single Sialic acid
and less carbohydrate
moieties.
? GM1 is a more complex
Ganglioside.
? GM1 is obtained from GM3.
Types Of Gangliosides
? Depending upon the Chemical structure and
Chromatographic separations
? More than 30 Types of Gangliosides are
isolated:
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
Sources Of GlycoSphingolipids
? Dietary has no much role
? All forms of Glycolipids Endogenously
Biosynthesized
? Utilized for Structure and Functional Role
Occurrence/Distribution
Of Glycolipids
? Glycosphingolipids are widely distributed
? In every cel and tissue of human body
? Occur particularly in outer leaflet of Cel
membrane/Glycocalyx /Cel Rafts
? They are richly present in nervous cel s.
?Glycolipids occur on the
outer surface of every
cel membrane as
component of
Glycocalyx /(Cel 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
? Blood group Antigens
? Embryonic Antigen
?Receptor sites for Hormones.
? Glycolipids of cel membrane serve as:
? Markers for cel ular recognition which
helps in:
?Cel Functioning
?Cel -Cel interaction
?Cel Signaling/Signal Transduction
?Anchoring sites for Antigens, Toxin and
Pathogens
?Cel Growth and Differentiation
? GM1 serve as receptor
/anchoring site to :
?Cholera toxin
?Tetanus toxin
?Influenza viruses
? The Cholera toxin on binding
to intestinal cel s
? 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.
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.
Lipidosis
Lipid Storage Disorders
Inborn Errors Of Lipid Metabolism
Lysosomal Storage Disorders
Rare Genetic
Lipid Associated Disorders
? Niemann Picks Disease
? Tay Sach's Disease
? Gauchers Disease
? Farbers Disease
? Krabbes Disease
? Sandhoff's Disease
Niemann Picks Disease
Autosomal Recessive Disorder
Lipid Storage Disorders
Related To Glycosphingolipids
Disorders Of GlycoSphingolipids
?Gaucher's Disease
?Tay Sach's Disease
?Farbers Disease
?Krabbes Disease
? Gaucher's Disease:
? Defect: Deficiency of Cerebroside degrading
enzyme Glucocerebrosidase.
? Biochemical Alteration: Abnormal
accumulation of Cerebrosides in tissues.
? Consequences: Affect normal function of
tissues where it is accumulated.
? Tay Sach's Disease:
? Defect: 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
Structural y Simple
Structural y complex
Ceramide linked with
Ceramide linked to Glucose,
Glucose or Galactose.
Galactose , NAGalactosamine ,and
NANA
2
Occur in White matter of Occur in Grey matter of brain and
brain and Myelin Sheaths. Ganglions.
3
Types :
Types :
Glucocerebrosides
GM1,GM2, GM3,GM4
Galactocerebrosides
4
Function : Conducts nerve Transfer Biogenic Amines
impulse
5
Related Disorder:
Related Disorder:
Gauchers Disease
Tay Sachs Disease
Lipoproteins
Lipoproteins
? Lipoproteins are types of
Compound Lipids /Conjugated
Proteins.
? Lipoproteins are macromolecules
formed by aggregation of :
? Lipids (Neutral and Amphipathic )
? Proteins( Apoprotein) in the
human body.
? Lipoproteins acquire polarity
(Hydrophilic Property)
? Lipoprotein serve as vehicles
for transportation of Neutral
and Amphipathic 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 central y 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
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
Features Chylomicrons VLDL
LDL
HDL
Site of
Small
Hepatocytes
Blood
Nascent HDL
Synthesis Intestine
Liver -80%
Circulation Liver
Intestine -20% From VLDL
Lipids %
99%
92%
80%
50%
Protein % 1%
8%
20%
50%
Rich Lipid TAG
TAG
Cholester Phospholipids
Form
Exogenous
Endogenous ol
Associate Apo B48, Apo Apo B100,Apo Apo B100, Apo A I,Apo A II
d
CI ,Apo E
CI,Apo CI ,Apo Apo CI,
Apo C I, Apo C II
Apoprote
E
Apo CI
Apo D & Apo E
in
and Apo E
Transport Dietary Lipids Liver
Liver
Extrahepatic
From
Intestine
Tissues
Transport Liver
Extrahepatic Extrahepa Liver
To
Tissues
tic Tissues
HDL Has Scavenging Role
OR
Reverse Transport of
Cholesterol
HDL Is Associated
With Enzyme LCAT
Responsible For
Cholesterol
Esterification And Its
Excretion
? HDL has scavenging role with
protective mechanism.
? HDL Transports Cholesterol from
Extrahepatic tissues back to Liver for
its excretion.
? HDL reduces risk of
Atherosclerosis.
? HDL clears the body Lipids and
do not al ow 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
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
Triacylglycerols Cholesterol
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 to
Apo(a)
300,000-800,000
LDL, Lp(a)
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, AI , AI I, 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 extracel ular
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 col ectively used
for
?Biological y 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)
I . Prostacyclins (PGI2)
I I. 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
? 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
fol owing 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 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 cel s).
?Autocrine in action that the
sites where they are produced.
? PGs exert their function
through G-Protein linked
membrane receptors.
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.
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
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 Therapeutical y
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 natural y increases
uterine contraction of
smooth muscles which
induces the delivery of baby.
? PGs can be therapeutical y 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.
Production of PGs
Promote
Fever , Pain , Nausea
Vomiting and Inflammation
Role Of PGs
In Immunity And Inflammation
? Prostaglandins are produced in more
amounts at the time of :
?Fever
?Pain
?Nausea and Vomiting
?Inflammation
? Provide non specific immunity to body
?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.
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
? They are 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
Structure And Types Of Leukotrienes
Leukotrienes Structure and Types
? Leukotrines are Hydroxy derivatives
possessing conjugated Trienes .
? Types of Leukotrienes:
? LTB4, LTC4, LTD4 and LTE4
Effect Of Leukotrienes
? Leukotrienes are components of
Slow Reacting Substances (SRS-A).
? SRS-A are released during Al ergic
reactions/Anaphylaxis.
?Leukotrienes are 100-
1000 times more
potent than Histamine
during al ergic
reactions.
?LTB4 is a potent
chemotactic agent.
(chemical substance which
mediates movement of
cel s).
? 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 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
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
Examples Of
Amphipathic Body Lipids
? Phospholipids
? Glycolipids
? Free Fatty acids
? Free Cholesterol
Features Of Amphipathic Lipids
? Structure has both polar and non polar groups
? Partial y soluble
? Orientation of groups:
?Polar group directed towards
water phase
?Non polar group directed in oil
phase/away from water.
Role Of Amphipathic Lipids
? Amphipathic Lipids have fol owing 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/neutral Lipids
? Liposomes:
? Agents for Drug /Gene carrier
Emulsions
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
smal , 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
surface tension.
? Emulsifying agents form a
surface layer of separating
main bulk of nonpolar Lipids
from aqueous phase.
?Emulsions are stabilized
by 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
I . 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 smal ,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
Micel es(~200 nm).
? Bile salts help in forming Mixed
Micel es.
?Mixed Micel es are
formed in Intestine after
digestion of Lipids.
?By an aggregation of
various forms of dietary
digested Lipids with Bile
salts.
? Aggregation of various
digestive end products of
dietary Lipids covered with a
peripheral layer of Bile salts
form Mixed Micelles in
intestinal lumen.
? Mixed Micel es contain the
non polar Lipids in the
interior portions and polar
Bile salts on the exterior.
Significance Of Mixed Micel es
? Mixed Micelles helps in
absorption of dietary Lipids
? From intestinal lumen into
intestinal mucosal cel s.
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 smal 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
Uses 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 Importances
Of Body Lipids
? The Role of various Body Lipids:
?Triacylglycerol
?Free Fatty acids
?Phospholipids
?Glycolipids
?Lipoproteins
?Cholesterol and Cholesterol Ester
?Eicosanoids
Body Lipids Functions
1.
Secondary Source of Energy
2.
Energy Storage Lipids- Long term use
3.
Thermal and Electrical Insulators
4.
Cushioning Effect and Shock absorber
5.
Shape and Contour to body
6.
Structural Lipids- Biomembrane components
7.
Cel antigens, receptors, anchoring sites
8.
Signal Transduction and Nerve Impulse conduction
9.
Lung Surfactant helps in normal respiration
10. Emulsifiers helps in Lipid digestion and absorption
11. Transport Lipids
12. Metabolic regulatory Lipids
1.
4.
Builds Membranes
Sources Of Energy, PUFAs
Signal Transmission
,Fat soluble Vitamins
2.
5.
Restores Abundant
FUNCTIONS OF LIPIDS
LUBRICATE
Energy
Cushioning Effect
3.
6.
Nervous Function
Electrical and Thermal
Lung Surfactant,
Insulators
Emulsifiers
Fatty acids of TAG is a
Source of Energy
Energy-Containing Nutrients (C and H)
H+
ATP Electron
Transport
Chain
CO2
O2
H2O
Good About Body Lipids
? Liberate 9 kcal per
? Regulates cell
gram of TAG.
function
? Major fuel at rest
? Maintains membrane
? Endurance Exercise
structure
? Stores Energy
? Improve nerve
function
? Source of :
? Provides flavors and
?Essential fatty acids
textures of foods
?Fat-soluble vitamins
? Helps us feel satiated
Disorders Associated To Lipids
? Obesity
? Atherosclerosis
? Respiratory Distress Syndrome
? Fatty Liver
? Hyperlipoproteinemias
? Hypolipoproteinemias
? Necrosis ,Oxidative damage of biomembranes due
to Lipid peroxidation
? Lipid Storage Disorders
Common
Lipids Associated Disorders
? Obesity
? Metabolic Syndrome
?Atherosclerosis
?Coronary Heart Disease
?Hypertension
?Diabetes Mel itus
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 Disorder Enzyme Defect and
Abnormal Accumulation of
1
Niemann Picks Disease Sphingomyelinase
Sphingomyelins
2
Gaucher's Disease
Beta Glucocerebrosidase
Glucocerebrosides
3
Krabbe's Disease
Beta Galactosidase
Galactocerebrosides
4
Tay Sach's Disease
Hexoseaminidase-A
Gangliosides
5
Farber's Disease
Ceramidase
Ceramides
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 Phospholipids wrt
Chemistry,Types,Nature,SourcesDi
stribution,Functions and
associated disorders of.
? What are Sterols? Describe the
structure, dietary sources,
properties & functions of
Cholesterol.
? Write Short Notes.
? Biomedical importance of various
forms of body Lipids
? Enlist various disorders associated to
Lipid forms with biochemical defect
and alterations.
? Essential fatty acids (PUFAs) & their
role in the body.
? Triacylglycerol/Neutral Fats- Structure
& Function.
? Rancidity- Causes & Prevention.
? Gycolipids/Cerebrosides/Gangliosides
? 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 Derived lipids & their functions
? Trans Fats and their harmful effects
? 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 of FAs
? 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 of Omega 3 and 6 types
? Enumerate Lipidosis with enzyme defects
? 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
? Enlist 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 human body Wax
? Differences of Fats and Oils
? Differentiate between
Cerebrosides and Gangliosides
? Occurrence and Role of TAG
? Definition of Compound Lipids
? Types of Compound lipids
? Sphingophospholipid Example
? Number and Names Of
Glycerophospholipids
? Hormonal role of Phospholipds
? Chemical composition of Lung
Surfactant
? Which Compound Lipid is classified
under classes of Lipid and Protein?
? Enzyme defect in Niemann Picks Disease
? Red Spot Macula is noted in which all
conditions
? In which disorder Ceramides get accumulated
in joints
? Emulsions and Liposomes results due to which
Lipid forms.
? On what criteria's TAG is selected as reservoir
of energy for long term use
? Enumerate various Lipid Storage disorders with
biochemical defect and abnormal accumulated
Lipid form
? What value of L/S ratio shows lung maturity and
immaturity?
? What are components of Lung Surfactant?
? What are roles of Lung surfactant?
? What form of energy source helps in endurance of
exercises of body?
? Which Lipids are associated to biomembranes?
? What are applications of Amphipathic Lipids?
? What clinical conditions shows
Hypercholesterolemia?
? Enzymes associated for Eicosanoids biosynthesis.
? Therapeutic roles of Prostaglandins
Biochemistry Department
This post was last modified on 05 April 2022