Alcoholysis and glyceride synthesis with immobilized lipase on controlled-pore glass of varying hydrophobicity in supercritical carbon dioxide

Lipases from Humicola lanuginosa and Candida antarctica lipase B were adsorbed onto methylated controlled-glass bends with varying degrees of hydrophobicity. The effect of support hydrophobicity on the amount of lipase adsorbed was studied. The immobilized lipases were examined for their activity in an alcoholysis reaction of cod liver oil with ethanol in supercritical carbon dioxide. Furthermore, the activity of the immobilized Humicola lanuginosa lipase in glyceride synthesis in supercritical carbon dioxide was studied. For both lipases investigated, the amount adsorbed decreased with decreasing hydrophobicity of the support; moreover, for Humicola lanuginosa lipase, the lipolytic activity was found to depend largely on the substrate and the hydrophobicity of the immobilization support. In the alcoholysis reaction, a highly hydrophobic carrier enhanced lipase activity whereas in glyceride synthesis, the reverse effect was observed. For Candida antarctica lipase, the support hydrophobicity did riot affect the activity of the lipase. In addition, the results showed that the lipid class composition of the reaction mixture reflected the lipolytic activity of the lipases immobilized on the different supports tested. (C) 1998 Elsevier Science Inc.