(593ac) Immobilization of Lipase B From Candida Antarctica B On Poly (methyl methacrylate) Epoxylated Support Aiming Biodiesel Production

Immobilization of enzymes and proteins on activated supports may be used to improve some enzyme properties in addition to allowing the simplification of reactor design. In this sense, supports containing epoxy groups may be very useful tools to stabilize proteins via uni or multipoint covalent attachment if the immobilization is properly designed. In this work, the support used for immobilization was Immobead 350-Chiralvision, which is a poly (methyl methacrylate) epoxylated with nonpolar characteristics support, diameter ranging between 300- 700µm. For the unipunctual immobilization, assays were performed varying the pH between 6-8 and ionic strength, an important factor, between 100-700mM. Best immobilization results were obtained at pH 7.5 and 700 mM, where recovery activity was around 25%. For multipoint immobilization, conducted at pH 10.05, the epoxylated support was modified by introducing amino groups, since the presence of amino groups allows a very rapid ionic adsorption of the proteins onto the support at low ionic strength. The new support has a layer of epoxy groups over a layer of ethylenediamine that is covalently bound to the support. Thus, this support has a great anionic exchanger power and a high number of epoxy groups. Immobilization was conducted at low ionic strength using amino-Immobead 350, while high ionic strength using conventional monofunctional epoxy supports was required. Furthermore, immobilization is expected to be much more rapid using amino-epoxy supports than employing conventional epoxy supports. Last but not least, the performance of both biocatalysts will be investigated in the synthesis of the ethyl oleate, aiming biodiesel production by esterification of acidic substrates.