The lipids they are fats and similar substances, which are found in plants and animals. Like carbohydrates and proteins, they constitute a very important group of organic molecules with pharmacological use and form a heterogeneous range of chemical functions.
Lipids are grouped, in principle, on the basis of their solubility characteristics; in general, they are soluble in organic solvents such as ether and chloroform and are insoluble in water.
Lipids can be classified into five groups according to their chemical structure:
- Fixed oils and fats: Glycerin esters with fatty acids. Example olive oil. Fixed oils that are solid at room temperature are commonly called greases. Example lard.
- Wax: High molecular weight monohydric alcohol esters with high molecular weight fatty acids. Example the fat obtained from whale sperm.
- Sterols: Alcohols containing the typical structure of the pentane phenanthrene (steroidal) cycle. Examples cholesterol and ergosterol.
- Phospholipids: Esters made up of glycerin, fatty acids, phosphoric acid and some nitrogenous compounds. The most important of this group are lecithins.
- Glycolipids: They are substances isolated from the brain and other sources which start from the hydrolysis of fatty acids, galactose and nitrogen compounds. Because the most common sugar present in these compounds is galactose, they are also called galactolipids. These compounds have no pharmaceutical application.
Lipids perform different types of biological functions:
- Function of energy reserve.
- Function structural forming the lipid bilayers of the cell membranes, in addition to the adipose tissue that gives consistency to the organs.
- Function regulatory, hormonal or cellular communication.
- Function shipping company. The transport of lipids from the intestine to its destination is carried out through its emulsion thanks to bile acids and lipoproteins.
- Function Biocatalyst, favoring or facilitating chemical reactions in our body.
More information - The vitamins
Source - Medicinal plants pharmacognosy