Final answer:
The enzyme that is inhibited by orlistat is pancreatic lipase, which is responsible for the breakdown of emulsified dietary fats into absorbable free fatty acids and monoglycerides in the small intestine.
Step-by-step explanation:
Fat-Digesting Enzyme Inhibited by Orlistat
The fat-digesting enzyme that is inhibited by orlistat is pancreatic lipase. Orlistat works by partially blocking the digestion and subsequent absorption of fats in the small intestine. During the digestive process, fats are emulsified by bile into smaller micelles, increasing the surface area for enzymes to act upon. Pancreatic lipase is the enzyme that then breaks down triglycerides in these emulsified fats into free fatty acids and monoglycerides, which can be absorbed by the body. When orlistat inhibits pancreatic lipase, the triglycerides are not hydrolyzed and are excreted undigested, which reduces the number of calories absorbed.
Lipid digestion is a critical process in which lipase enzymes play a crucial role. Bile, produced by the liver and stored in the gallbladder, is released into the small intestine where it emulsifies dietary lipids. The emulsified lipids are then broken down by pancreatic lipase, allowing for their absorption into the body. The inhibition of this enzyme by orlistat thus decreases the ability of the body to absorb dietary fats.