Immobilization of lipase on a polymer carrier containing epoxy and

Abstract

An immobilized lipase is prepared for transesterification of oils, fats or phospholipids in a reaction system containing a very small amount of water such as 50 to 2,000 ppm. The lipase may be a phospholipase such as phospholipase A.sub.2. In a first embodiment, lipase from a microorganism of the genus Rhizopus, Mucor, Alcaligenes or Candida is immobilized on the surface of a hydrophobic, insoluble organic polymer carrier having pores of an average diameter of 10 nm or larger. A solution of lipase is contacted with the polymer carrier for 10 minutes to 40 hours to covalently bond the lipase to the carrier. The immobilized lipase is dried under reduced pressure to a water content of 0.5 to 30 wt %. In a second embodiment, lipase is immobilized on the surface of a polymer carrier such as a hydrophobic, insoluble organic polymer carrier having a pore diameter of 5 to 1,000 nm and having a functional group capable of binding lipase in a aqueous solution and an anion-exchange group on the surface. Preferably, the functional group is an epoxy group and the anion-exchange group is a tertiary amino group. The lipase may be obtained from the same microorganism as in the first embodiment or from another lipase-producing microorganism. Immobilization can be carried out as in the first embodiment. It is preferred to contact a solution of lipase with the polymer carrier in the presence of a fatty acid or derivative thereof for 10 minutes to 10 hours to covalently bond the lipase to the polymer carrier.