Lipase-catalyzed hydrolysis of canola oil in supercritical carbon dioxide

The effect of pressure, temperature, and CO2 flow rate on the extent of conversion and the product composition in the enzyme-catalyzed hydrolysis of canola oil in supercritical carbon dioxide (SCCO2) was investigated using lipase from Mucor miehei immobilized on macroporous anionic resin (Lipozyme IM). Reactions were carried out in a continuous flow reactor at 10, 24, and 38 MPa and 35 and 55 degrees C. Supercritical fluid chromatography was used to analyze the reaction products. A conversion of 63-67% (triglyceride disappearance) was obtained at 24-38 MPa. Mono- and diglyceride production was minimum at 10 MPa and 35 degrees C. Monoglyceride production was favored at 24 MPa. The amount of product obtained was higher at 24-38 MPa due to enhanced solubility in SCCO2. Complete hydrolysis of oil should be possible by increasing the enzyme load and/or decreasing the quantity of the oil substrate. There was a drop in triglyceride conversion over a 24-h reaction time at 38 MPa and 55 degrees C, which may be an indication of loss of enzyme activity. Pressure, temperature, and CO2 flow rate are important parameters to be optimized in the enzyme-catalyzed hydrolysis of canola oil in SCCO2 to maximize its conversion to high-value products.