Covalent immobilization of Pseudomonas fluorescens lipase onto Eupergit CM

Abstract

Immobilization of enzymes is an important field of study as the reusable heterogeneous biocatalysts designed tremendously reduce production costs by efficient recycling and control of the catalytic processes. In the present study, the immobilization of Pseudomonas fluorescens lipase was performed via covalent attachment of lipase onto oxirane activated supports (Eupergit CM). Their wide specificity has rendered lipases into the most commonly-used enzymes in organic chemistry, resulting in an urgent need to effectively immobilize these enzymes. 100,0±0,2% immobilization yield and 170±1,1% activity yield were achieved by optimizing the immobilization conditions (ratio of matrix/enzyme, pH of buffer medium, molarity of buffer medium, duration of immobilization). The best results were achieved when the lipase was immobilized at pH 9 at room temperature (25 oC) for 120 hours. The operational and storage stabilities of the immobilized enzymes were determined as well. No decrease in the activity of immobilized enzyme during 20 consecutive batch reactions was observed. Furthermore, the immobilized enzymes showed high storage stability as they retained their activity for 20 days of usage. The obtained immobilized Pseudomonas fluorescens lipase can be used for the biodiesel production, oil hydrolysis and various important esterification reactions.