| abstract |
The present invention discloses an industrial scale method to obtain 1-kestose by the use of a recombinant fructosyltransferase (FTF), isolated from Festuca arundinacea, expressed constitutively in a non-saccharolytic yeast. In this invention, the recombinant FTF type sucrose:sucrose 1- fructosyltransferase (1-SSTrec) is produced constitutively, stable and at high yield, both in the culture supernatant and in intact cells of the host Pichia pastoris. Hence, the invention additionally provides a method for 1-SST production at industrial scale. The recombinant enzyme is then used for mass production of short-chain fructooligosaccharides (FOS), specifically 1-kestose, from sucrose. The method of the present invention establishes conditions that allow conversion rates where the synthesized FOS constitute above 55% (w/w) of the total sugars in the reaction mixture and the 1-kestose content reaches values higher than 90% (w/w) of the total FOS fraction. |