A new approach to evaluate immobilization of β-galactosidase on Eupergit® C: structural, kinetic, and thermal characterization

Química Nova

Anna R. C. Braga²  Marceli F. Silva¹  José V. Oliveira¹  Helen Treichel¹  Susana J. Kalil² 

[1] ,Universidade Federal do Rio Grande Escola de Química e Alimentos Rio Grande RS ,Brasil

关键词: binding kinetics;    β-galactosidase;    scanning electron microscopy;   

DOI  :  10.5935/0100-4042.20140128

来源: SciELO

【 摘 要 】

This study aimed to evaluate β-galactosidase immobilization. For this purpose, the ionic strength of the buffer, reaction time, amount of the immobilization support, and pH were evaluated by a central composite design. Assay 8, which consisted of 1.5 mol L-1 phosphate buffer (pH 7.5) and a reaction time of 2 h, produced the maximum yield. Eupergit® C (400 mg) was subsequently used as an immobilization support. Immobilization kinetics wereinvestigated, and a significant increase in the yield was obtained after immobilization compared with that obtained from assay 8 (22.0 U mL-1 vs. 15.6 U mL-1). The enzyme efficiency of actuation was evaluated using o-nitrophenyl-β-D-galactopyranoside and lactose, with lactose providing better results. The reuse of β-galactosidase was evaluated, and more than 50% of the initial enzyme activity was maintained after five cycles of use. Enzyme characterization revealed that immobilization improved some aspects of the thermostability of β-galactosidase.

【 授权许可】

CC BY-NC   
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