Poster Presentation 1B-45

Immobilization of a Commercial Bacterial Alpha-amylase on Nylon-6 Microbeads

Oscar García-Kirchner*, Ma. Eugenia Gómez-Montes, Carlos R. Sosa-Aguirre

Departamento de Bioprocesos

UPIBI-IPN. Av. Acueducto S/N Col. Barrio La Laguna, Ticomán.

México, 07340 D. F. MÉXICO

Phone: (5) 57-29-60-00 ext. 56345

Fax: (5) 57-29-60-00 ext. 56305

E-mail: ogarcia@acei.upibi.ipn.mx

Recently, immobilized enzyme technology has been a subject of great interest because of a number of advantages of immobilized enzymes over native enzymes. A wide variety of carriers and methods have been used for the immobilization of various enzymes.

This presentation describes the immobilization of TAKATHERM on nylon-6 microbeads, which were previously activated with glutaraldehyde, using polietilenimine as spacer. The industrial enzymatic preparation donated by ENMEX was obtained from submerged fermentation using Bacillus licheniformis, which was partially purified prior to the immobilization procedure.

The obtained results showed that the enzyme coupling method used in this study was experimentally simple and gave a high yield of immobilized protein. The enzyme activity of immobilized Takatherm was 663.8 U/g of microbeads. The optimum pH of Takatherm bound on nylon microbeads was found to be 6.5 and 5.5 for native enzyme, the maximum activity with immobilized enzyme was observed at 65ºC, 10ºC higher than native enzyme. The kinetic parameters as Michaelis constant and maximum rate were determined for the immobilized enzyme and compared with those for the free form. Km for immobilized and native α-amylase were very similar. The Km for immobilized enzyme was 125 mg/mL and 0.94 mg/mL for native form. Storage stability of enzyme immobilized was evaluated during 30 days.