Dry powder preparation of inulin fructotransferase from Arthrobacter aurescens SK 8.001 fermented liquor

Difructosan anhydrides III (DFA III) are usually obtained by inulin conversion with inulin fructotransferase (IFTase). IFTase liquor is difficult to store for a long time, which could greatly restrict its application and DFA III production. To meet DFA III scale-up preparation, this work was explored to research dry powder preparation of IFTase from Arthrobacter aurescens SK 8.001 fermented liquor by ultrafiltration concentration, ammonium sulfate precipitation and freeze drying. IFTase powder (10.2 g) was obtained from IFTase precipitation (126.4 g) and its specific activity determined was 16.4 U/mg. Dry powder of IFTase could maintain over 120 days at different temperatures. These results showed that it is easy to scale up DFA III preparation for industrial capacity.