The digestive proteases of langostilla (pleuroncodes planipes,decapoda): their partial characterization,and the effect of feed on their composition

• 1.1. Three methods of recuperating and preserving enzyme activity from freshly-caught langostilla were assessed. In the pressing and acetone extract methods, the recovered specific activity was similar.
• 2.2. Protease activity was higher between 6.5 and 8 pH, and was sensitive to high temperatures.
• 3.3. In PAGE and serine inhibition assays, one fraction resembled bovine trypsin.
• 4.4. The composition of proteins and molecules bearing protease activity from the hepatopancreas and stomach of both fed and starved animals was similar, indicating proteases are not induced but constitutive.