Enzyme encapsulation in magnetic chitosan-Fe₃O₄ microparticles

Abstract

Two simple procedures for the preparation of magnetic chitosan enzyme microparticles have been investigated and used for the immobilisation of endophytic fungus Cercospora kikuchii lipase as model enzyme. In the first case, lipase was entrapped in Fe₃O₄-chitosan microparticles by cross-linking method, while in the second case magnetic immobilised derivatives were produced using spray drying. Immobilised enzymes showed high enzyme activity retention and stability during storage without significant loss of activity. Glutaraldehyde Fe₃O₄-chitosan powders presented a higher lipase activity retention and storage stability than the others preparations. However, the immobilised derivatives produced by cross-linking showed higher enzyme activity after reuse cycles. The results proved that the magnetic Fe₃O₄-chitosan microparticles are an effective support for the enzyme immobilisation since the immobilised lipase showed best properties than the free form.

• Bioencapsulation
• Cercospora kikuchii
• chitosan
• enzyme immobilisation
• lipase
• spray dryer

Declaration of interest

The authors report no conflict of interest. The authors alone are responsible for the content and writing of this article. This study was supported by the State of São Paulo Research Foundation (FAPESP). T. A. Costa-Silva received a fellowship from FAPESP (Grant # 2011/00743-8).