Digestive enzymes DR. S.P. KAMBLE

1. Digestive enzymesDR. S.P. KAMBLE

2. Enzymes help in the breakdown of food, in a process called chemical digestion. Food contains carbohydrates, proteins and lipids, so a wide range of enzymes is needed. • Carbohydrases break down carbohydrates • Proteases break down protein • Lipases break down lipids

4. Carbohydrate digestion involves two stages: • First the breakdown of starch to maltose is catalysed by the enzyme amylase in the mouth and the lumen of the small intestine. • Secondly the breakdown of maltose to glucose is catalysed by the enzyme maltase inside the mucosa cells of the small intestine.

6. Protein digestion in the lumen of the gut starts with an enzyme called endopeptidase that catalyses the breakdown of proteins to form polypeptides. • An enzyme called an exopeptidase catalyses the breakdown of polypeptides to produce dipeptides. • Inside the cells of the mucosa dipeptidase enzymes catalyse the breakdown of dipeptides into amino acids.

8. Lipid digestion only occurs in the lumen of the small intestine. • Lipid digestion cannot start in the stomach because conditions are too acidic for the lipase enzymes. • Bile salts found in bile produced by the liver break down the fat droplets into smaller droplets. • This process is called emulsification. It increases the surface area for the lipase enzymes to work on. • Lipase from the pancreas catalyses the breakdown of lipids into fatty acids and glycerol.