Preparation and modification of chitosan particles for Rhizomucor miehei lipase immobilization

Chitosan particles, suitable as immobilization support, were prepared by precipitation and modified by reductive amination in order to graft linear aliphatic chains of 12 carbon atoms to their native amine groups. Their physical characterization was performed by different techniques: differential sc...

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Detalles Bibliográficos
Autores: Palla, Camila Andrea, Pacheco, Consuelo, Carrin, Maria Elena
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2011
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/56155
Acceso en línea:http://hdl.handle.net/11336/56155
Access Level:acceso abierto
Palabra clave:Acidolysis
Adsorption
Chitosan
Reductive Amination
Rhizomucor Miehei Lipase
Structured Lipids
https://purl.org/becyt/ford/2.9
https://purl.org/becyt/ford/2
Descripción
Sumario:Chitosan particles, suitable as immobilization support, were prepared by precipitation and modified by reductive amination in order to graft linear aliphatic chains of 12 carbon atoms to their native amine groups. Their physical characterization was performed by different techniques: differential scanning calorimetry (DSC), X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), air-water contact angle analysis, among others. Lipases from Rhizomucor miehei (RM) were immobilized by adsorption at low ionic strength onto different modified chitosan microspheres. Their ability to catalyze the acidolysis reaction between sunflower oil and palmitic and stearic free fatty acids was evaluated in a solvent medium. Effects of modification conditions on the particles hydrophobic character, lipase adsorption and acidolysis activity were investigated. Modified particles were bigger and more hydrophobic than unmodified ones. The most active biocatalyst achieved a change in the composition of palmitic and stearic acid from a value of 9.6% in the original oil to 49.1% in the final structured lipids, representing an almost 3-fold enzyme hyperactivation. This high conversion was maintained during 7 reuse cycles (168 total hours). The results demonstrated that the chitosan modification was effective in order to adsorb and hyperactivate RM lipases.