Production of maltosylfructose (erlose) with levansucrase from Bacillus subtilis

Levansucrase (E.C.2.4.1.10) from B. subtilis was used in a synthesis reacti on for the production of maltosylfructose using maltose as acceptor and suc rose as the fructosyl donor. The effect of various parameters was studied i n order to minimize the hydrolysis of sucrose and the production of levan. A high total solute concentration (240 g/L of sucrose and maltose) reduced hydrolysis to 20%. Further reductions could only be obtained by decreasing the sucrose/maltose concentration ratio. Optimum fructoside production was obtained at around 70% sucrose conversion, as afterwards. the product was h ydrolyzed by the enzyme. Under these conditions the yield could be as high as 70-80% with respect to converted sugar or 46% with respect to total sucr ose in the reaction. Thc product was purified and identified as O-alpha-D-g lucopyranosyl-(1 -4)-O-alpha-D-glucopyranosyl-(1-2)-beta-fructofuranoside, a non-reducing trisaccharide known as Erlose which occurs naturally in Aphi s pomi honeydew.