Lipase catalyzes the hydrolysis of what substrate?

Lipase is an enzyme specifically designed to catalyze the hydrolysis of triglycerides. Triglycerides are the primary form of fat stored in the body and consist of glycerol and three fatty acids. The hydrolysis reaction facilitated by lipase breaks down triglycerides into glycerol and free fatty acids, which can then be utilized for energy or other metabolic processes.

The focus of lipase activity on triglycerides is crucial for digestion, as the breakdown of dietary fats is essential for nutrient absorption. Once triglycerides are hydrolyzed, the resulting fatty acids and glycerol can be easily absorbed by the intestinal cells.

Starch, glucose, and glycogen are not substrates for lipase; they are carbohydrates. Instead, starch is broken down by amylase, glucose is a simple sugar, and glycogen is a polysaccharide that serves as a storage form of glucose in animals, which is typically broken down by enzymes such as glycogen phosphorylase. Thus, the specificity of lipase for triglycerides establishes its vital role in lipid metabolism.