Digestion of lipid

Digestion of lipid

Definition of digestion

Brocken down of big food particles into small food particles, which can be absorbed and use as a nutrients for the body.

Classification of lipid

1. Simp;e fat -

a. Triglyceride / Neutral fat 

b.  cholesterol .

2. Compound fat -

a. Phospholipid

b. Glycolipid

c. Lipoprotein

3. Derived fat -

a. Prostaglandin

b. Leuketrin

• We are lipid intake with food in the form of triglyceride mostly while some parts of cholesterol and cholesterol ester.

• The enzyme which help in digestion of lipid called lipolytic  enzyme.  

Digestion of lipid in mouth

Saliva contain a lipolytic enzyme called lingual lipase, but this enzyme not act on food in mouth and engulfed with food.

Digestion of lipid in stomach

Gastric juice contain a lipolytic enzyme called gastric lipase, which act on triglyceride and converts into fatty acids and glycerol.

Digestion of lipid in small intestine

Intestine have two juices...

1. Pancreatic juice

2. Intestinal juice / succus entericus

Pancreatic juice

It contain enzymes...

1. Pancreatic lipase - it act on triglyceride and convert into fatty acids.

2. Cholesterol ester hydrolase - it act on cholesterol ester  and convert  into free cholesterol.

3. Phospholipase - it act on phospholipid and converts into free phospholipid and fatty acid.

4. Bile salt activated lipase - it activate bile for emulsification of fat. This enzyme act firstly and activated bile for emulsification of fat like fatty acid and cholesterol  because these are insoluble in water where as phospholipid are soluble in water.    

Intestinal juice / succus entericus

It contain only a lipolytic enzyme called intestinal lipase (weak enzyme) , which act on triglyceride and convert into fatty acid and glycerol ( it's function is negligible ).

Absorption

Lipid absorbed from small intestine.

• Less then 12 carbon fatty acid absorb in the form of micelles.
• More then 12 carbon fatty acids absorb in the form of chylomicrons.