5-80: Porcine pancreatic lipase purification on poly(ethylene glycol)-potassium phosphate aqueous two-phase system

Lipase (EC.3.1.1.3) catalyses the hydrolysis of triglycerides at the oil-water interface, synthesis of esters and transesterification in microaqueous conditions. For the application is necessary its purification, which requires delicate enough steps to preserve the biological activity. This study examined the application of the aqueous two-phase system (ATPS) to purify porcine pancreatic lipase, studying the influence of molecular weight and concentration of poly(ethylene)glycol (PEG), tie line length (TLL), potassium phosphate concentration, NaCl addition and temperature in the partition. The enzyme was further purified in PEG-8000, presenting more recoveries at the top phase to the lowest TLL, concentrations of PEG and potassium phosphate (purification factor of 2.8-fold), the increase of these variables represses the purification. The addition of NaCl did not promote the purification of the enzyme and temperatures of 14.5^oC were more effective in the purification (PF = 4.0-fold). This study demonstrated that aqueous two-phase system is a well suitable methodology for lipase purification.