FIVE DIGESTIVE JUICE

Saliva: This is the combined secretion from the salivary glands and the small mucus secreting glands of the lining of the oral cavity. Saliva consists of water, mineral salts & enzyme ptyalin. Ptyalin split cooked starch to maltose. Maltose further breaks down into glucose with the help of the enzyme maltase in the small intestine.

Gastric Juice: It is a strong acidic liquid secreted into the stomach by gastric glands. Its main components are digestive enzymes pepsinogen and rennin, hydrochloric acid and mucus. Pepsinogen with hydrochloric acid converted in to active Pepsin, which digests proteins up to the stage of peptone. Rennin coagulates caseinogens of milk. Gastric lipase digests fat to some degree. Hydrochloric acid helps to hydrolyze foodstuffs.

Pancreatic juice: Produced by the pancrease and enter into the duodenum. It contains a variety of enzymes. They include trypsinogen, chymotrypsinogen, elastase, carboxypeptidase, pancreatic lipase and pancreatic amilase. Pancreatic juice is alkaline in nature due to the high concentration of bicarbonate ions. This is useful in neutralizing the acidity, allowing for effective enzymic action. Trypsinogen and chymotrypsinogen with enteropeptidase converts peptones in to peptides and polypeptides. pancreatic amilase converts all digestible polysaccharides not affected by ptyalin to disaccharides.Lipase converts fats to faty acid and glycerol.

Bile: A digestive chemical that is produced in the liver, stored in the gall bladder, and secreted into the duodenum. The main components of bile are water, bile salts, bile pigments, and cholesterol. Bile salts act as emulsifying agents in the digestion and absorption of fats. Cholesterol and bile pigments from the breakdown of hemoglobin are excreted from the body in the bile.

Intestinal juice : Secrets from the glands of small intestine . It consists of water, mucus & enzyme enteropeptidase. Its function is to complete the process begun by pancreatic juice; the enzyme trypsin exists in pancreatic juice in the inactive form trypsinogen, it is activated by the intestinal enteropeptidase. Trypsin can then activate other protease enzymes and catalyze the reaction.

Ref: PMD, OSL, Bangladesh.