Role of Digestive Enzymes in Digestion

Digestive enzymes and gastrointestinal hormones are present during digestion, and they both play a significant part in breaking down complicated compounds into simpler ones.

Human bodies include three different types of digestive enzymes. Based on the reactions they catalyze, they are categorized as follows:

• Amylase enzymes convert carbs and starches into sugars.
• Proteins are broken down into amino acids by the protease enzyme.
• Lipase converts lipids, or fats and oils, into glycerol and fatty acids by the action of the lipase enzyme.
• The enzyme nuclease converts nucleic acid into nucleotides.

Key Terms: Digestion, Lipase, Protease, Nuclease, Enzymes, Hormones, Amino Acids, Pancreas, Lipids, Proteins, Fats

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Digestion

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The process of digestion involves breaking down large, intractable food molecules into more manageable, easily absorbed smaller molecules. Digestion is a form of catabolism that is frequently divided into two processes based on how food is broken down. The methods are:

• Mechanical Digestion: Large meal portions are physically broken down into smaller pieces during this procedure so that the enzymes can readily digest them.
• Chemical Digestive: In the case of chemical digestion, the body can use the smaller molecules that are created when food particles are broken down by the digestive enzymes.

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Types of digestive enzyme

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In human bodies, there are primarily three different types of digestive enzymes. Based on the reactions they catalyze, they are categorized as follows:

• Amylase Enzymes: They convert carbs and starches into sugars.
• Protease Enzyme: It converts proteins into amino acids.
• Lipase Enzyme: It converts lipids, or fats and oils, into glycerol and fatty acids.
• Nuclease: They divide nucleic acid into nucleotides using an enzyme called nuclease.

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Role of Digestive Enzyme and Hormones in Digestion

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The role of different enzymes in digestion is listed below:

1. Lipase Enzyme: It is produced in the mouth. In the mouth, lipase begins the process of breaking down lipids and fats.
2. Salivary Amylase: It is produced in the mouth. The mouth is where the digestion of carbohydrates begins. 

• The salivary glands' amylase is responsible for breaking down complicated carbs into simpler sugars or smaller chains.
•  Ptyalin is another name for it.

3. Lysozyme: It is produced in the mouth. Food can contain unnecessary nutrients, such as germs or viruses, and lysozyme works as an antibacterial agent.
4. Pepsin: It is produced by the "chief cells" of the stomach, also known as pepsinogen in its inactive state. 

• The stomach acid then converts pepsinogen into its active form, pepsin.
• It assists in separating food's protein into smaller components known as peptides and amino acids. 
• Protein digestion begins in the stomach, whereas the mouth is where carbs and fats are first broken down.

5. Gastric Lipase: It is produced in the stomach. The gastric main cell in the fundic portion of the stomach's mucosa secretes gastric lipase, an acidic lipase. 

• The ideal pH range for stomach lipase is 3-6. 
• It is in charge of breaking down the dietary fat in our stomach.

6. Hydrochloric acid (HCL): It is produced in the stomach. 

• It aids in the denature of eaten proteins, the destruction of any bacteria or viruses still present in food
• The activation of pepsinogen to produce pepsin.

7. Factor intrinsic: The stomach's parietal cells create it. Its own self-transformation and nutrient uptake.
8. Mucin: It is produced in the stomach. It protects the inner lining. Due to its extreme acidity, it kills a variety of bacteria and viruses found in food.
9. Gastrin: It is produced in the stomach and is primarily an endocrine hormone

• It is produced by the G-cell in the stomach.
• It encourages the production of numerous intrinsic factors as well as HCL in parietal cells.

10. Trypsinogen: Initially inactive, they become active and turn into trypsin, which aids in the breakdown of proteins. The enterokinase enzyme assists in activating trypsinogen.
11. Chymotrypsinogen: It is produced in the pancreas, and is one of the components of pancreatic juices. This substance is already there but is inactive until it is changed by enterokinase into active chymotrypsin.
12. Carboxypeptidase: It is produced in the pancreas

• It is one of the components of pancreatic juices. 
• Carboxypeptidase is a protease that digests proteins by removing the terminal amino acid group.

13. Pancreatic lipase: It is produced in the pancreas, and is one of the components of pancreatic juices. Triglycerides are broken down into two fatty acids and a monoglyceride by pancreatic lipase. 
14. Cholecystokinin: It is also produced in the pancreas, and is one of the components of pancreatic juices. Duodenal I-cells secrete a special peptide called cholecystokinin in response to chyme that contains a lot of fat.
15. Secretin: Secretin is produced in the intestine. Secretin is an endocrine hormone that the duodenal S type cell secretes in response to the gastric chyme's decreasing acidity.
16. Cholecystokinin (CCK): Is it produced in the intestine, and is a special peptide that the duodenal "I cells" release in response to chyme that contains a lot of fat or protein. 

• Additionally, it causes the gallbladder to contract more, releasing previously stored bile into the cystic duct
• Eventually into the common bile duct and into the second anatomic position of the duodenum via the ampulla of vater.

17. Gastric inhibitory peptide (GIP): It is also produced in the intestine. Duodenal mucosal cells produce a type of peptide known as gastric inhibitory peptide (GIP), which slows down gastric movement.

Also Read:

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Things to Remember

• Digestion involves breaking down large food molecules into smaller molecules.
• Four main types of Digestive Enzymes are amylase, lipase, nuclease, and peptidase
• Three different enzymes produced in the moth are, lipase, salivary amylase and lysozyme
• Proteases are found only in the stomach
• The stomach contains, mucous neck cell, glial cells, and peptic cells
• The amount of enzymes your body produces tends to decline as one grows old.
• Chymotrypsinogen is produced in the pancreas, and is one of the components of pancreatic juices.

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Previous Year Questions

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