Figure 1. Principles of enzyme immobilization.

Figure 2. Structures of polysaccharides used as carriers for enzymes.

Figure 3. Synthetic polymer carrier; macroporous particle structure. Scanning electron microscopy (SEM) pictures of Eupergit® C 250L. The spherical shape and porous structure is easily recognizable.(Reproduced courtesy of S. Menzler, Degussa/Röhm GmbH.)

Figure 4. Functional groups available for Sepabeads®.

Figure 5. Derivatization of a silica carrier; activation with glutaraldehyde, and binding of an enzyme by a free amino group (e.g., lysine).

Figure 6. Covalent binding of penicillin amidase to a carrier matrix by epoxide groups (Katchalski-Katzir and Krämer, 2000).

Figure 7. (a) Mechanism of glucose isomerization (Makkee, Kieboom, and van Bekkum, 1984). (b) Chemical equilibria in solution.

Figure 8. Scheme of procedures for immobilization of glucose isomerase. (a) Novo: cross-linking of cells (Pedersen and Christensen, 2000). (b) Genencor: principle of isolation of crystalline enzyme. (c) Adsorption onto a composite ion-exchange matrix formed by extrusion with 50% polystyrene, 20% TiO ₂, 30% DEAE-cellulose; d _p 400–800 µm (Antrim and Auterinen, 1986).

Figure 9. Hydrolytic carbohydrate reactions. (a) Sucrose with invertase; (b) lactose with β-galactosidase; (c) raffinose with α-galactosidase; (d) inulin with inulinase.

Figure 10. Transglycosidations by glycosyltransferases. (a) Sucrose isomerization; (b) cyclodextrin synthesis.

Figure 11. Scheme of industrial isomaltulose production (Rose and Kunz, 2002).

Figure 12. Different products with sucrose analogues as substrates. Enzymatic synthesis of 1-kestose, 1-nystose, and their analogues by β-fructofuranosidase of A. niger. Structures of fructo-oligosaccharides: (I) commercial products, (II) mannose-, (III) galactose-, and (IV) xylose-substituted analogues (Zuccaro et al., 2008; Seibel and Buchholz, 2010).

Figure 13. Scheme of the production of l-amino acids by amino acylases (Chibata et al., 1987). (a) Reaction; (b) reactor system and peripheral instrumentation.

Figure 14. Synthesis of aspartame using thermolysin.