CHARACTERISTICS OF TRANSGLYCOSYLATION REACTION OF CYCLODEXTRIN GLUCANOTRANSFERASE IN THE HETEROGENEOUS ENZYME REACTION SYSTEM USING EXTRUSION STARCH AS A GLUCOSYL DONOR

Characteristics of the intermolecular transglycosylation reactions of saccharides and glucosides by cyclodextrin glucanotransferase (CGTase) in the heterogeneous enzyme reaction system rising swollen extrusion starch as a glucosyl donor were analyzed. The transglycosylation yield and rate were significantly increased compared to the conventional re action system using liquefied starch as the glucosyl donor. Various mo nosaccharides composed of the same configuration of 2-, 3-, and 4-OH w ith the D-glucopyranoside such as D-xylose, D-glucose, L-sorbose, and myo-inositol were found to be goad accepters for the transglycosylatio n reaction. Several glucosides such as stevioside and hesperidin were also identified as the suitable glucosyl accepters. The optimal transg lycosylation reaction condition using stevioside as the glucosyl accep tor was also determined. The heterogeneous transglycosylation reaction system shows a few distinct advantages; minimized accumulation of oli gosaccharides, easy removal of residual extrusion starch after reactio n, and simplified purification of transglycosylated products, therefor e, which will facilitate the industrial application of the various tra nsglycosylation reactions. (C) 1998 Elsevier Science Inc.