Kinetic studies of Mucor miehei lipase in phosphatidylcholine microemulsions

Ethanol-oleic acid esterification by a free and microencapsulated lipase from Mucor miehei, using dodecane as solvent and phosphatidylcholine as surfactant, was studied. The initial esterification rate was influenced by the water content in the biphasic system. Kinetic studies with free and microencapsulated enzyme showed that the microencapsulation led to an increase of the kinetic parameters (Vmax and Km), probably due to an increase of the interfacial area. The reaction rate was also affected by the shaking rate, the temperature and the pH. The optimal temperature and pH achieved were, respectively, 40 degrees C and 4.5 using free enzyme, and 50 degrees C and 6 using microencapsulated enzyme.