Modification of Sardine Oil by Immobilized Bacterial Lipase

Determination was made of the rates of icosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) incorporation into triolein and sardine oil triglyceride (TG). Three kinds of lipases (Lipase OF from Candida cyrindracea, Lipase A from Aspergillus sp. and Lipase TOYO from Chromobacterium viscosum) were first immobilized onto Celite 545. A preliminary study was then performed to determine optimum conditions for acidolysis by conducting this process between triolein and palmitic acid, using these immobilized lipases including LipozymeTH (Mucor miehei lipase was immobilized on a macroporous anion exchange resin). Optimum water contents for Lipase OF, Lipase A, Lipozyme, and Lipase TOYO reaction systems were 20.38%, 10.24%, 6.38~10.38%, and 5.18%, respectively, and the optimum immobilized lipase amount was about 250 mg for any of the four lipases. Under the above conditions, the acidolysis of triolein between pure EPA and then DHA was carried out. EPA incorporation rate was found highest in the system using Lipase OF (25.09%), whereas in the case of DHA, it was highest in the system using Lipase TOYO (23.02%). Finally, acidolysis of sardine oil TG with an EPA, DHA concentrated free fatty acid mixture (EPA+DHA : 68.83%) was carried out and the results examined. As a result of the low incorporation rates of EPA and DHA into the original sardine oil TG, the percentage of DHA in the reactant TG doubled in the reaction systems using Lipase TOYO and Lipozyme.報