Biotechnology Progress, Vol.32, No.3, 657-665, 2016
Luffa cylindrica Sponges as a Thermally and Chemically Stable Support for Aspergillus niger Lipase
The use of biopolymer compounds as matrices for enzyme immobilization is currently a focus of increasing interest. In the present work we propose the use of Luffa cylindrica vegetable sponges as a support for the lipase extracted from Aspergillus niger. Effectiveness of immobilization was analyzed using Fourier transform infrared spectroscopy, elemental analysis and the Bradford method. An initial enzyme solution concentration of 1.0 mg/mL and an immobilization time of 12 h were selected as the parameters that produce a system retaining the highest hydrolytic activity (84% of free enzyme). The resulting biocatalyst system also exhibited high thermal and chemical stability, reusability and storage stability, which makes it a candidate for use in a wide range of applications. Kinetic parameters for the native and immobilized lipase were also calculated. The value of the Michaelis-Menten constant for the immobilized lipase (0.47 mM) is higher than for the free enzyme (0.21 mM), which indicates that the adsorbed enzyme exhibits a lower affinity to the substrate than native lipase. (C) 2016 American Institute of Chemical Engineers Biotechnol.