Fructosyltransferase immobilization

MBR have also found use in the production of polysaccharides. MBR provide a simplified method for producing these materials, which are, typically, obtained in small quantities from natural sources by elaborate procedures. Hicke et al. [4.64] reported the synthesis of inulin (poly-j8-(2,l)-frutan) in a MBR with the aid of fructosyltransferase immobilized in the membrane s porous structure. Inulin, with a high molecular weight and low polydispersity, was continuously synthesized from sucrose, as the substrate passed through the MF membrane. 

Polyfructan (inulin) of MW 30-50 million was synthesized from sucrose with fructosyltransferase (FTF, inulin sucrase from Streptococcus mutans) immobilized by photoinitiated graft copolymerization with poly(2-aminoethyl methacrylate) in the pores of a 3.0 pm microfiltration membrane (Hicke, 1999). 

Keywords Biocatalysis, Enzyme engineering, Fructosyltransferases, Glucosyl-transferases, Immobilization, Oligosaccharides, Reaction engineering... 

Two epoxy-activated related supports, Sepabeads EC-EP3 and EC-EP5 (Figure 11.3), were assayed for the immobilization of A. aculeatus fructosyltransferase. By combination of nitrogen isotherms and mercury porosimetry analyses, the textural properties of both carriers were determined (Table 11.3). As shown, both samples... 

The fructosyltransferase mined from the commercial preparation Pectinex Ultra SP-L is quite stable towards pH, temperature, and the presence of chemicals. The A aculeatus fructosyltransferase showed a high transferase hydrolase raho that provides it with great potential for oligosaccharide synthesis. The enzyme can be easily immobilized on epoxy-activated supports for better performance. Further studies are required to draw mechanishc conclusions on the nature of the kinetics observed with this fructosyltransferase. 

The synthesis of f. is performed by action of immobilized fructosyltransferase on sucrose (pH 5.5, 50-60 °C), the latter acting as an acceptor for the transferred fructosyl groups. Final product composition DP 3-5 56.7% DP >5 5.6% mono- and disaccharides 39.7% (the latter may be removed by ion-exchange chromatography). 

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