Activity of bacterial lipases at chilling temperatures

Two Pseudomonas aeruginosa two Pseudomonas fluorescens three Aeromonas hydr ophila, one Aeromonas caviae, two Staphylococcus aureus and two Serratia ma rcescens strains were tested for their ability to digest tributyrin at temp eratures ranging from -2 degreesC to +7 degreesC over a period of 38 days u sing a modified agar-diffusion test. Hydrolysis was observed at ail of the temperatures investigated, with she exception of S. marcescens lipases at - 2 degreesC. A decrease in storage temperature was associated with a signifi cant reduction of enzyme activity but no complete inactivation - even at -2 degreesC. initial reactions occurred after 3 days. For practical applicati ons, it can be concluded that during storage of chilled pro ducts, lipolyti c activity can occur provided that enzyme synthesis has taken place before chilling has started. (C) 2001 Academic Press.