Question

The enzyme involved in the hydrolysis of starch to maltose is
(a) Protease
(b) Amylase
(c) Lactase
(d) Maltase

Answer 1

In the salivary gland, the enzyme involved in starch- to- maltose hydrolysis is active. The three forms are alpha, beta, and gamma. It is also present in humans in the secretion of the pancreas and helps in starch intracellular digestion.

Complete step by step answer:
Starch is in plants used as food reserves. It is a glucose polymer. It is formed by the attachment of glucose molecules by glycosidic bonds.
The disaccharide formed by the binding of alpha 1,4 glucose molecules is maltose.
Amylase is an enzyme that contributes to the starch digestion process. This works on the starch's glycosidic bonds and transforms them into simpler compounds.
When food passes to the small intestine, the rest of the starch molecules are mainly catalyzed by pancreatic amylase into maltose. In the first section of the small intestine (duodenum) , the region into which the pancreatic juices empty, this step in the digestion of starch occurs. Other enzymes ultimately break down the by- products of amylase hydrolysis into glucose molecules, which are rapidly absorbed through the intestinal wall.

Additional information:
- Maltase is an enzyme that catalyzes the simple sugar glucose hydrolysis of the disaccharide maltose. The enzyme is present in plants, bacteria, and yeast; it is thought to be synthesized by cells of the mucous membrane lining the intestinal wall in humans and other vertebrates.
- During digestion, the pancreatic or salivary enzymes called amylases partly transform starch into maltose; maltase secreted by the intestine then converts maltose into glucose. The glucose thus produced is either used by the body or stored as glycogen (animal starch) in the liver.
- Lactase is an enzyme that many species make. It is found in the brush boundary of humans and other mammals' small intestines. For the complete digestion of whole milk, lactase is essential; it breaks down lactose, a sugar that gives sweetness to milk.
- Protease is an enzyme that catalyzes (increases the rate of) proteolysis, the breakdown of proteins into smaller polypeptides, or single amino acids, called peptidase or proteinase. They do this by hydrolysis, a reaction where the water breaks bonds, by cleaving the peptide bonds within proteins.
So, the correct answer is, ‘(b) Amylase’.

Note: Amylase is a digestive enzyme that catalyzes starch (in Latin it means amylum) hydrolysis into sugars. Amylase is found in humans' saliva and certain other animals, where the chemical process of digestion starts. They are glycoside hydrolases that operate on alpha 1,4 glycosidic bonds.