Easy to Pharmacy & learnt. II Sem. B.Pharm - 2nd Year.

1. - Biomolecules [
“lipids” ] -

2. = Lipids =
• “ Lipids may be regarded as organic substances relatively insoluble in
water, soluble in organic solvents ( alcohols , ether etc. ), actually or
potentially related to fatty acids & utilized by the living cells” .
❑ ‘AMPHIPATHIC’ , has “Carboxyl Group” at polar end-hydrophilic.
❑ Types of amphipathic –
➢ Unsaturated : Contains double bond.
➢ Saturated : Ex. Animal fats.

3. = Classification of lipids =
• Lipids divided into most common four parts :
• 01. Simple lipids.
• 02. Complex lipids.
• 03. Derived lipids.
• 04. Miscellaneous lipids.

4. - Simple lipids -
❖ The simple lipids include fats , oils & waxes. These simple lipids are derivatives
of lipid- like substance call “fatty acids”..
❖ Esters of fatty acids with glycerol.
• Mainly of two types –
❑ A. Fats & Oils – These are esters of fatty acids & glycerol.
-Difference b/w fats & oils is physical.
❑ B. Waxes – Esters of fatty acids + alcohol other than glycerol.
- Cetyl alcohol is most commonly used.
- Waxes used in the preparation of candles, lubricants , cosmetics ,
ointments & polishes..

5. - Complex lipids -
• These are esters of fatty acids with alcohols containing Additional groups such as
Phosphate, carbohydrates , proteins etc..
❖ They divided into four parts =
• ( A ). Phospholipids : Contains “ Phosphoric acid”.
❑ They divided into two sub types –
• [ 01 ]. Glycerophospholipids = Ex. Lecithin , cephalin etc.[contain glycerol as the alcohol ]
• [ 02 ]. Sphingophospholipids = Ex. Sphingomyelin. [ alcohols in this group of phospholipids ]
• ( B ). Glycolipids = Ex. Cerebrosides & gangliosides etc.
• ( C ). Lipoprotein = Complex of lipids with proteins.
• ( D ). Other complex lipids = Sulfolipids , Amino lipids..

6. = Derived lipids =
• Thee are the derivatives of hydrolysis of simple & complex lipids
which possess the characteristics lipids.
• These include –
❑ Lipid soluble vitamins.
❑ Steroid hormones.
❑ Hydrocarbons.
➢ Ketones bodies.
➢ Mono & diacylglycerol etc..

7. - Miscellaneous lipids -
❑ A large number of compounds possess characteristics
of lipids , such compounds come under this category.
❑ Ex : carotenoids, squalene, hydrocarbons like
pentacosone & terpenes etc.

8. - Functions of lipids -
❑ They are the concentrated fuel reserve of the body.
❑ They serve the source of fat soluble vitamins [ A, D, E, K ].
❑ Lipids are important as cellular metabolic regulators.
❑ Lipids dissolve the ingredients & forms a mixture.
❑ Combine with protein in four to form gluten.
❑ Ex : water , milk, buttermilk, & fruit juice etc..