Inactivation of proteases and lipases by ultrasound

Abstract

The inactivation of phospholipase A 2, α-chymotrypsin, trypsin and porcine pancreatic lipase by heat and manothermosonication (MTS), and the simultaneous application of heat and ultrasound under moderate pressure, has been studied in different treatment media. MTS sensitivity varied strongly for the different enzymes. Whereas phospholipase A 2 was almost insensitive to MTS treatments, α-chymotrypsin and porcine lipase MTS inactivation was much faster than heat inactivation. Trypsin heat inactivation was very different at low than at high temperatures. At low temperatures, it did not follow first order kinetics, contrary to what happened at high temperatures. MTS accelerated trypsin inactivation only at low temperatures. MTS changed also the inactivation order of trypsin (at low temperatures), α-chymotrypsin and porcine lipase; whereas heat inactivation of these enzymes did not follow first order kinetics, MTS inactivation fitted this well.