Improving the properties of chitosan as support for the covalent multipoint immobilization of chymotrypsin

Changing gel structure and immobilization conditions led to a significant improvement in the covalent multipoint attachment of chymotrypsin on chitosan. The use of sodium alginate, gelatin, or κ-carrageenan, activation with glutaraldehyde, glycidol, or epichlorohydrin, and addition of microorganisms...

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Detalles Bibliográficos
Autores: Adriano, Wellington, Mendonça, Dany, Rodrigues, Dasciana, Mammarella, Enrique José, Giordano, Raquel
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2008
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/19798
Acceso en línea:http://hdl.handle.net/11336/19798
Access Level:acceso abierto
Palabra clave:Covalent Multipoint Immobilization
Chymotrypsin
Chitosan
https://purl.org/becyt/ford/2.11
https://purl.org/becyt/ford/2
Descripción
Sumario:Changing gel structure and immobilization conditions led to a significant improvement in the covalent multipoint attachment of chymotrypsin on chitosan. The use of sodium alginate, gelatin, or κ-carrageenan, activation with glutaraldehyde, glycidol, or epichlorohydrin, and addition of microorganisms followed by cellular lysis allowed the modification of the gel structure. Immobilization yields, recovered activities, and stabilization factors at 55 and 65 °C were evaluated. Enzyme immobilization for 72 h at pH 10.05, 25 °C and reduction with NaBH4 in chitosan 2.5%−carrageenan 2.5%, with addition of S. cerevisiae 5% and activation with epichlorohydrin led to the best derivative, which was 9900-fold more stable than the soluble enzyme. This support allowed an enzyme load up to 40 mg chymotrypsin × ggel−1. The number of covalent bonds, formed by active groups in the support and lysine residues of the enzyme, can explain the obtained results. SEM images of the gel structures corroborate these conclusions.