SOURCE. Porcine Pancreas.
Prepared by chromatography, lyophilized.
Contains predominately trypsin and chymotrypsin.
Contains ca 0.2% elastase.
White powder, highly soluble in 0.01 M HCl, >75 mg/ml.
Trypsin activity 17.0 to 20.0 units per mg of solid.
Chymotrypsin activity 16 to 19 units per mg of solid.
Assays done in 0.1 M Tris pH 8.3 containing 0.15 mM N-benzoyl-Phe-Val-Arg-pNA (Trypsin)(EPC No. NB32) or 0.15 mM N-succinyl-Ala-Ala-Pro-Phe-pNA (chymotrypsin)(EPC No. SG554) and 2 to 5 mg protease.
One unit will hydrolyze 1 µM substrate per minute at 25°C.
Protease assay on casein.
Substrate-buffer is 0.1 M Tris pH 7.5 containing 12.5 mg per ml of solubilized casein. One unit will hydrolyze 1 mg of casein per minute at 37°C. Protease activity >130 units per mg of solid.
Store 5°C. Stable 1-2 years.