Which enzyme activity can be determined using a dilute olive oil emulsion substrate, whose hydrolyzed product is monitored as a decrease in turbidity or light scatter?

Which enzyme activity can be determined using a dilute olive oil emulsion substrate, whose hydrolyzed product is monitored as a decrease in turbidity or light scatter?

• A. Alkaline phosphatase
• B. Amylase
• C. Lipase
• D. Trypsin

Answer: (C)

Lipase is the enzyme that acts on fats present as triglycerides in an oil-in-water emulsion. Olive oil emulsion provides those triglyceride substrates in a dispersed form, so the enzyme can access and hydrolyze them. As lipase cleaves the fatty acids from the glycerol backbone, the emulsion structure destabilizes and the fat droplets are broken down, producing products like free fatty acids and monoglycerides. This disruption of the oil droplets leads to less light being scattered, so turbidity or light scatter decreases over time. The change in turbidity directly reflects lipase activity on the fat substrate. The other enzymes target different substrates: alkaline phosphatase acts on phosphate esters, amylase on starch, and trypsin on proteins, and their typical assays do not use an olive oil emulsion whose turbidity tracks their activity.

Lipase is the enzyme that acts on fats present as triglycerides in an oil-in-water emulsion. Olive oil emulsion provides those triglyceride substrates in a dispersed form, so the enzyme can access and hydrolyze them. As lipase cleaves the fatty acids from the glycerol backbone, the emulsion structure destabilizes and the fat droplets are broken down, producing products like free fatty acids and monoglycerides. This disruption of the oil droplets leads to less light being scattered, so turbidity or light scatter decreases over time. The change in turbidity directly reflects lipase activity on the fat substrate.

The other enzymes target different substrates: alkaline phosphatase acts on phosphate esters, amylase on starch, and trypsin on proteins, and their typical assays do not use an olive oil emulsion whose turbidity tracks their activity.