DIGESTIVE PROTEASE, LIPASE AND AMYLASE ACTIVITIES IN STAGE-I LARVAE OF THE AMERICAN LOBSTER, HOMARUS-AMERICANUS

1. 1. Digestive protease, lipase, and amylase of Stage I larvae of the American lobster Homarus americanus are characterized. 2. 2. A sensitive method for detection of crustacean lipase was developed using an latroscan which combines thin-layer chromatography and flame ionization detection to quantify free fatty acids generated by lipase digestion. 3. 3. pH optima of the three enzymes occurred at or near the pH of gastric fluid. 4. 4. A time course study demonstrated slight increases in protease and amylase activities during the first larval stage, regardless of whether the lobsters were fed or not, whereas lipase activity was constant. © 1989.