Essential fatty acid (EFA): Structure, Functions

 Essential fatty acid (EFA)

The fatty acids that cannot be synthesised by the body and therefore should be supplied in the diet are known as essential fatty acids. Chemically they are polyunsaturated fatty acids (PUFA), namely linoleic acid, linolenic acid and arachidonic acid.

Structure

CH3 (CH2)4 CH = CH-CH2-CH=CH(CH2)7 COOH

Linoleic acid

CH3 (CH2)4 CH = CH-CH2-CH=CH -CH2-CH = CH(CH2)7 COOH

Linolenic acid

CH3 (CH2)4 CH = CH-CH2-CH=CH -CH2-CH = CH-CH2-CH=CH-(CH2)3 COOH

Arachidonic acid


Functions

·           EFAs are requried for the membrane structure and functions.They are necessary for the maintenance of growth, reproduction and good health.

·           They are important for the transport of cholesterol, formation of lipoportein and prevention of fatty liver.

·           They serve as precursor for prostaglandin biosynthesis.

·           They prolong clotting time and increase fibrinolytic activity.

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