Isolation of Natural Product (Cholesterol).C

Extraction of Cholesterol
I N T H I S E X P E R I M E N T , Y O U W I L L:



Gain experience in the use of several techniques used to isolate chemical substances from their natural source.
Isolate the steroid cholesterol from egg yolk.



I N T R O D U C T I O N:

Living organisms are amazing in their ability to speci?cally and ef?ciently
synthesize complicated organic compounds. Many of the familiar organic materials we use daily are natural products, including substances used as (1) ?avorings (peppermint, spearmint, cinnamon), (2) foods (carbohydrates, fats, proteins), (3) polymers (rubber, cotton, silk), (4) building materials (wood), (5) drugs (penicillin, streptomycin), and (6) vitamins.
Naturally occurring animal or vegetable fats and oils are glycerides (triesters of glycerol and long-chain fatty acids). The fatty acids differ in chain length and degree of unsaturation, but they commonly contain 12 to
18 carbon atoms. Glycerides containing a high percentage of saturated acids are solids at room temperature and are called fats. Those composed of a higher percentage of unsaturated acids have lower melting points, are liquids at room temperature, and are called oils