Preparation and characterization of different immobilized and chemically modified preparations of lipase B from Candida antarctica: is it the activation energy a good indicator of the biocatalyst expressed activity?

Lipase B from Candida antarctica immobilized on octyl (via interfacial activation) and octyl-vinyl sulfone (covalently attached) agarose beads via different immobilization protocols was submitted to amination and/or glutaraldehyde modifications. The catalytic performance of the resulting biocatalysts significantly varied across different substrates: using octyl-CALB with the double modification, activity increased 3.5 fold versus triacetin and decreased by 5 % using R-methyl mandelate, while using the covalent biocatalyst, activity increase by 2.

Development of a biocomposite based on alginate/gelatin crosslinked with genipin for β-galactosidase immobilization: Performance and characteristics.

In this work, we studied the development of a biocomposite formulated with alginate and gelatin, crosslinked with genipin for application as support for β-galactosidase immobilization. Also, the biocomposites with the immobilized enzyme were characterized by thermal analyses and SAXS (size, density, and interconnectivity of alginate rods) for a detailed analysis of the microstructure, as well as the thermal and operational stabilities of the enzyme. The structural modifications of the biocomposite determined by SAXS demonstrate that the addition of both genipin and enzyme produced a significant reduction in size and density of the Ca(II)-alginate rods.

Highly stable novel silica/chitosan support for β-galactosidase immobilization for application in dairy technology.

β-d-Galactosidase is an important enzyme in the dairy industry, and the enzyme from the yeast Kluyveromyces lactis is most widely used. Here, we report immobilization of the enzyme on a silica/chitosan composite support, devised to have 10% and 20% chitosan (SiQT10 and SiQT20, respectively). Morphological and textural characterizations showed that chitosan is dispersed in micrometric regions in silica.

Efficient enzyme-assisted extraction of genipin from genipap (Genipa americana L.) and its application as a crosslinker for chitosan gels.

Enzyme-assisted extraction in liquid-liquid two-phase aqueous system was applied for the first time in order to extract genipin from genipap. The effect of different commercial enzymes, their concentrations, and extraction parameters were investigated. Moreover, chitosan gels were prepared, crosslinked with glutaraldehyde or genipin and characterized by their textural and rheological properties.