Immobilization of Aspergillus niger lipase on chitosan-coated magnetic nanoparticles using two covalent-binding methods

OSUNA-SÁNCHEZ, YOLANDA; SANDOVAL-CORTÉS, JOSÉ; SAADE, H.; R. G. LÓPEZ; JOSÉ LUIS MARTÍNEZ HERNÁNDEZ; EDITH MADAÍ COLUNGA URBINA; GABRIELA DE LA CRUZ; ELDA PATRICIA SEGURA CENICEROS; .FERNANDO J. ARÉVALO; ZON, MARÍA ALICIA; FERNÁNDEZ, HÉCTOR; ANNA ILINÁ

BIOPROCESS AND BIOSYSTEMS ENGINEERING

SPRINGER

Lugar: Berlin; Año: 2015

1615-7591

Abstract Aspergillus niger lipase immobilization by covalentbinding on chitosan-coated magnetic nanoparticles(CMNP), obtained by one-step co-precipitation, was studied.Hydroxyl and amino groups of support were activatedusing glycidol and glutaraldehyde, respectively. Fouriertransform infrared spectrometry, high-resolution transmissionelectron microscopy and thermogravimetric analysisconfirmed reaction of these coupling agents with the enzymeand achievement of a successful immobilization. Thederivatives showed activities of 309.5 ± 2.0 and266.2 ± 2.8 U (g support)-1 for the CMNP treated withglutaraldehyde and with glycidol, respectively. Immobilizationenhanced the enzyme stability against changes ofpH and temperature, compared to free lipase. Furthermore,the kinetic parameters Km and Vmax were determined forthe free and immobilized enzyme. Km value quantified forenzyme immobilized by means of glutaraldehyde was 1.7times lowers than for free lipase. High storage stabilityduring 50 days was observed in the immobilized derivatives.Finally, immobilized derivatives retained above80 % of their initial activity after 15 hydrolytic cycles. Theimmobilized enzyme can be applied in various biotechnologicalprocesses involving magnetic separation.