Difructosan anhydrides III preparation from sucrose by coupled enzyme reaction

Difructosan anhydrides III (DFA III) preparation was usually obtained by inulin hydrolysis with inulin fructotransferase (IFTase). The fructofuranosidic linkages of inulin were the same as fructooligosaccharides (FOS), which was synthesized by sucrose with fructosyltransferase (FTase). FOS was mainly composed of 1-kestose (GF2), nystose (GF3) and fructofuranosylnystose (GF4), and nystose was observed to be the smallest substrate for IFTase to synthesize DFA III. So sucrose, much cheaper than inulin, was considered to produce DFA III by coupled FTase and IFTase reaction. DFA III yield was obtained about 100 mg/g (DFA III weight/sucrose weight) through this method. The results demonstrated the high potential of the coupled enzyme reaction as a novel DFA III producing method.