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1. MSCDFSM BIOCHEMISTRY
LIPIDS AND PROTEINS

2. LIPIDS :
1. These are the heterogenous group of compounds occurring in both plants and animals.
2. Lipids are insoluble in water but soluble in ether ,chloroform and benzene
3. Neutral fats and oils derived from animal and plant sources are called neutral lipids on
hydrolysis they break down into glycerol and fatty acids .
STRUCTURE AND CLASSIFICATION
lipids
Neutral fat wax
phospholipids sulpholipids aminolipids
lipoproteins
glycolipids
Compound
lipids
Simple lipids Derived lipids

3. SIMPLE LIPIDS
1. These are esters of fatty acids with various alcohol.
2. This include neutal fat and wax
3. Neutral fat are the ester of fatty acids and glycerol
4. Waxes are the fatty acids with alcohol other than glycerol
COMPOUND LIPIDS
1. These are the esters of fatty acids containing group in addition to alcoholand fatty acids.
2. Eg phospholipids and glycolipid etc
3. Phospholipids are lipids that contain phosphoric acids in adition to glycerol and fatty acid
DERIVED LIPIDS
1. These are the compounds derived from other groups on hydrolysis.
2. The groups are fatty acids, glycerol,steroids,alcohols fatty aldehyde ,ketones etc
FATTY ACIDS
When neutral fat hydrolyse ,it gives fatty acids fatty acids occur naturally in food .
it is represented by
0
R C OH
R- hydrocarbon chain (CH3-CH2-CH2…….)

4. SATURATED AND UNSATURATED FATTY ACIDS
SATURATED FATTY ACID
• When fatty acid have all single
bonds
• These are solid at room temp
• General Formula
CH3(CH2)Ncooh
• It has polar end with –COOH
group and non –polar end with
hydrocarbon chain.
UNSATURATED FATTY ACIDS
• When fatty acids have one or
more double bonds .
• These are liqid at room temp
• General formula
H H
C C

5. SATURATED FATTY ACIDS
Fatty acids with less carbon atoms are readily soluble in water .and solubility decrease with
increase in carbon atom .saturated fatty acids with less than 10 carbon atoms areliquid at
room temp and more than 10 are solid at room temp.
Melting point of fatty acids increase with increase carbon atom .
Eg. Butyric acid in butter ,lauric acid in coconut oil
UNSATURATED FATTY ACIDS
These are of two types .PoLyunsaturated fatty acids (PUFA) & Monounsaturated fatty acids
(MUFA)
MUFA has single double bond and PUFA has two or more double bond
POSITIONAL ISOMERISM
Unsaturated fatty acid exhibit positional isomerism .fatty acid with same molecular formula
and same number of double bonds ,may differ in ocation of double bonds this resut in
positional isomerism .eg.oleic acid
GEOMATRICAL ISOMERISM
Two hydrogen attached to two carbon atom joined by double bonds exibit geometrical
isomerism .if both hydrogen atom are placed on same side of double bond ,its called cis
isomer .
And if hydrogen is placed on either side of double bond its called trans isomers
Eg .oleic acid , elaidic acid.naturally occurring unsaturated fats are of cis confugration

6. location of double bond can be easily identified by α,β,ω etc .α carbon is carbon next to
carboxylic group .and ω is the last carbon of the chain .LINOLENIC acid is an omega 6 fatty
acid because double bond is six carbon away from omega carbon .ALPHA LINOLENIC acid is
omega 3 fatty acid because it has double bondthree carbon away from omega carbon. To be
more clear , n3 or ω3 fatty acid have dobe bond between carbon atom 3 and 4 but no double
bond between 6 and 7 carbon atom .on the other hand , n6 or ω6 fatty acids have double bond
between 6 and 7 carbon atom .
Eg of unsaturated fatty acid are :oleic acid in olive oil,linoleic acid in veg oils ,linolenic acid in
linseed oil.
ESSENTIAL FATTY ACID
These are important or essential fatty acid that are not made by our body and thus it is
essential to survive.it has to be provided by external source like food or supplements .
Eg .Omega 6 essential fatty acid (linoleic acid ) in sunflower ,sufflower ,corn oils etc
omega 3 essential fatty acid (linolenic acid ) in flex seed and hemp seeds .