Highly Efficient Fructooligosaccharides Production by an Erythritol-Producing Yeast Yarrowia lipolytica Displaying Fructosyltransferase.

Currently, fructooligosaccharides (FOS) are industrially transformed from sucrose by purified enzymes or fungi cells. However, these methods are expensive and time-consuming. An economical approach to producing FOS using erythritol-producing yeast cells was described in this study. Fructosyltransferase from Aspergillus oryzae was displayed on the cell surface of Yarrowia lipolytica, resulting in an engineered strain capable of transforming sucrose to FOS. An amount of 480 g/L FOS was produced within 3 h in a solution of 800 g/L sucrose and 5 g/L cells (dry cell weight, DCW) at pH 6.0 and 60 °C, with a yield of 60% of total sucrose and a productivity of 160 g/(L·h). The yeast pastes from the erythritol industry can be repeatedly used as the whole-cell catalysts at least 10 times by this newly developed approach. This efficient method is attractive for the large-scale production of FOS from sucrose.