Brazilian Journal of Chemical Engineering
versão impressa ISSN 0104-6632versão On-line ISSN 1678-4383
ADRIANO, W. S. et al. Stabilization of penicillin G acylase by immobilization on glutaraldehyde-activated chitosan. Braz. J. Chem. Eng. [online]. 2005, vol.22, n.4, pp.529-538. ISSN 0104-6632. http://dx.doi.org/10.1590/S0104-66322005000400005.
The objective of this work was to study enzyme immobilization on chitosan activated with glutaraldehyde, aiming to produce a cheap biocatalyst. Two different immobilization strategies were studied: one-point and multipoint covalent attachment to the solid matrix. The multipoint covalent attachment derivative had an 82% immobilization yield. It was 4.9-fold more stable than the free enzyme at 50°C and 4.5-fold more stable than soluble enzyme at pH 10.0. The one-point derivative had an 85% immobilization yield. It was 2.7-fold more stable than the free enzyme at 50°C and 3.8-fold more stable than soluble PGA at pH 10.0. Results indicated that chitosan can be loaded with PGA above 330 IU/g. Intraparticle diffusive effects, however, limited hydrolysis of penicillin G catalyzed by those derivatives at 37°C and 25°C. Operational stability assays were performed and the multipoint derivative exhibited a half-life of 40 hours.
Palavras-chave : Stabilization of enzymes; Penicillin G acylase; Chitosan and immobilization of enzymes.