AN U S H I J AI N
R O L L N O . : 1 2
PAP E R I
M S c I
Fatty Acid is “a carboxylic acid consisting of a
hydrocarbon chain and a terminal carboxyl group,
especially any of those occurring as esters in fats and oil”.
• Fatty acids are straight chain hydrocarbons possessing
a COOH group at one end.
• The carbon next to the COOH group is known as “α”, the
next carbon “β”, and the last position is labelled as a "ω”
TYPES OF FATTY ACID :
A. Saturated fatty acids: No
C-C double bonds.
B. Unsaturated fatty acids: C-
C double bonds.
i. Monounsaturated fatty
acids: Only one C-C
ii. Polyunsaturated fatty
acids: Two or more C-C
ESSENTIAL FATTY ACIDS
• Essential fatty acids are fatty acids that cannot be
synthesized within the human body, and therefore must
be obtained from the diet.
• There are two families of essential fatty acids: omega-3
(n−3) and omega-6 (n−6) fatty acids. As these fatty acids
are not saturated with hydrogen (H) atoms (and contain
more than one double bond between the atoms) they are
called ' Polyunsaturated Fatty acids ' (PUFAs).
• Most PUFAs are of plant and fatty fish origin.
FUNCTION OF ESSENTIAL
• Formation of healthy cell membranes
• Proper development and functioning of the brain and
• Production of hormone-like substances called
• Responsible for regulating blood pressure, blood
viscosity, vasoconstriction, immune and
ω-3 and ω-6 FATTY ACIDS
• The food sources of ω-3 and ω-6 fatty acids are fish and
shellfish, flaxseed (linseed) and flaxseed oil, hemp seed, olive
oil, soya oil, canola (rapeseed) oil, chia seeds, pumpkin
seeds, sunflower seeds, leafy vegetables, and walnuts.
• In all ω-6 fatty acids (FA) , the first double bond is located
between the sixth and seventh carbon atom from the methyl
end of the fatty acid and in all ω-3 FA, the first double bond is
located between the third and fourth carbon atom counting
from the methyl end of the fatty acid.
• Example :
Alpha-linolenic acid (ALA).
Linoleic acid (LA).
SYNTHESIS OF ω-6 FATTY ACID
• Linoleic Acid is the precursor of all the omega-6 fatty
• It is converted in gamma-linoleic acid in the reaction
catalyzed by Δ6-desaturase; then it is elongated to
form dihomogamma-linolenic acid, which in turn is
desaturated in the reaction catalyzed by Δ5-desaturase
to form arachidonic acid which is elongated to form
docosatetraeonic acid (adrenic acid).
CLINICAL SIGNIFICANCE OF ω-6
The clinical significance of omega fatty acids lies primarily in the
role they play in inflammatory events in the body.
• The most important omega-6 PUFA is arachidonic acid. When
cells are stimulated by a variety of external stimuli,
arachidonic acid is released from cell membranes through the
action of phospholipase A2 (PLA2).
• The released arachidonate then serves as the precursor for
the synthesis of the biologically active eicosanoids, the
prostaglandins (PGs), thromboxanes (TXs), and leukotrienes
• The arachidonate-derived eicosanoids function in diverse
biological phenomena such as platelet and leukocyte
activation, signaling of pain, induction of bronchoconstriction,
and regulation of gastric secretions.
BENEFITS OF ω-6 FATTY ACIDS
ω-6 fatty acids with ↑ GLA content may help to :-
• Relieve the discomforts of PMS, endometriosis, and
• Reduce the symptoms of eczema and psoriasis.
• Clear up acne and rosacea.
• Prevent and improve diabetic neuropathy.