Desenvolvimento de processos de produção de fruto-oligossacarídeos em reator enzimático utilizando enzimas com atividade de transfrutosilação imobilizadas

Abstract

Fructooligosaccharides (FOS) correspond to an important class of prebiotics that present several beneficial effects to the consumer and technological properties suitable for application in different food products. In view of this, the present work aimed to develop a production process for fructo-oligosaccharides using FOS-forming enzymes in their immobilized form. First, different strains producing β-fructofuranosidase (FFase) by Solid State Fermentation (SSF) were investigated, with the best production observed by the Aspergillus tamarii strain URM4634 using soy bran as a substrate (UH = 209.1 U mL-1 and UTF = 53.9 U mL-1). The enzyme was biochemically characterized and evaluated in relation to its kinetic and thermodynamic parameters, it was found that in fact the enzyme was a phase with transfructosylating activity, being thermostable at temperatures commonly used in the production of FOS (50°C). Studies involving the immobilization of commercial preparation Pectinex Ultra SP-L with transfructosylating activity (UH = 378.0 U mL-1 and UTF = 301.7 U mL-1) were also carried out in chitosan (CS) and in Fe3O4–chitosan-magnetic nanoparticles (MNPs-CS). The different immobilization techniques proved to be effective, with immobilization yields of 95.9% and 94.8%, in CS and MNP-CS, respectively. Both methods of immobilization conferred greater thermostability to the enzyme, as can be observed by the kinetic and thermodynamic parameters. Both immobilized forms of the enzyme showed good reuse capacity and are stable to storage. FOS production was carried out by enzymes immobilized on both supports, the best results being obtained by the preparation immobilized in MNP-CS (101.56 g L-1) by a batch process compared to immobilized in CS via continuous process in an enzymatic bed reactor packaged (25.73 g L-1). Based on the results obtained, it can be concluded that two immobilized biocatalysts were developed with proven application in production and FOS using the commercial enzyme Pectinex Ultra SP-L and another with promising results for industrial applications, mainly for inverted sugar production, involving the FFase from A. tamarii immobilized by covalent bond in chitosan.