LIPASE PURIFICATION BY VARIOUS TECHNIQUES AND ITS THERMOSTABILIZATIONIN PRESENCE OF SURFACE-ACTIVE ADDITIVES

Crude porcine pancreatic lipase was purified by removing water-insolub le impurities (residual lipid material) associated with it by a conven tional method, using hydrotropic additives and by liquid coacervate ex traction. Maximum yield with good recovery of activity was obtained wh en hydrotropes were used to separate the associated lipids from lipase . The thermostability of the enzyme was also checked in the solutions of additives such as sodium butyl monoglycol sulfate (Na-BMGS), prolin e and Triton X-114. In Na-BMGS solutions above a concentration of 0.2 mol dm(-3) the lipase activity decreased beyond 50 degrees C whereas i n 1 mol dm(-3) proline solution it was retained even at 80 degrees C, showing a good thermostabilizing effect. However, in the presence of T riton X-114 the enzyme was completely inactivated with increase in tem perature. (C) 1998 SCI.