Site pages
Current course
Participants
General
Topic 1
Topic 2
Topic 3
Topic 4
Topic 5
Topic 6
Topic 7
Topic 8
Topic 9
Topic 10
Topic 11
Topic 12
Topic 13
Topic 14
Topic 15
Topic 16
Topic 17
Topic 18
Topic 19
Topic 20
Topic 21
Topic 22
Topic 23
Topic 24
Topic 25
Topic 26
Topic 27
6.1.2 Classification of lipids
Lipids are classified as simple lipid, compound lipid and derived lipids.1.Simple Lipids They are esters of fatty acids with various alcohols. They are divided into two groups a. fat and b. wax.
a. Fats: They are esters of fatty acids with glycerol. They are also called triglyceride or neutral fat. A fat in the liquid state at room temperature is known as oil. Monoglycerides and diglycerides are also present in natural lipids.
b. Waxes: They are fatty acid esters of alcohols other than glycerol. The fatty acids present are long-chain acids. The alcohol may be aromatic or aliphatic.
2.Compound lipids Compound lipids are esters of fatty acids containing groups in addition to an alcohol and a fatty acid. a.Phospholipids: Lipids containing fatty acids, an alcohol and a phosphoric acid residue. They frequently have nitrogen containing bases and other constituents. They are classified in to two groups 1. Glycerophospholipids 2. Glycolipids or Sphingophospholipids i)Glycerophospholipids: In glycerophospholipids, the alcohol is glycerol. e.g. Phosphatidyl choline, Phosphatidyl ethanolamine, Phosphatidylserine, Phosphatidyl inositol and cardiolipin
ii) Sphingophospholipids: In sphingophospholipids, the alcohol is sphingosine e.g. Sphingomyeline
b.Glycosphingolipids: Lipids containing a fatty acid, sphingosine and carbohydrate. e.g. Cerebrosides, Gangliosides
c.Other compound lipids: Other compound lipids include sulfolipids, proteolipids and steroids.
3. Derived lipids: These include free fatty acids, glycerol, sterols and alcohols. Fatty aldehydes, ketone bodies, hydrocarbons, lipid-soluble vitamins, and hormone, acyglycerols (glycerides), and cholesterol.
|