Continuous production of alpha,alpha-trehalose by immobilised fungal trehalose phosphorylase

Immobilisation of trehalose phosphorylase from Schizophyllum commune by ads orption onto anion-exchange materials stabilised the enzyme activity at 30 degrees C by approx. 35-fold. Immobilised and free enzymes showed similar p H-dependence of activity but different inactivation behavior above 30 degre es C. A fixed-bed enzyme reactor produced alpha,alpha-trehalose at a stable substrate conversion of 80% with a productivity of 2.6 g l(-1) h(-1) for 7 2 h. Inhibition of trehalose phosphorylase by phosphate limited the product ivity of a direct conversion of starch into alpha,alpha-trehalose.