Conversion of Sucrose into Cellobiose Using Sucrose Phosphorylase, Xylose Isomerase and Cellobiose Phosphorylase

Cellobiose was synthesized from sucrose by coupling reactions of sucrose phosphorylase, xylose isomerase and cellobiose phosphorylase in the presence of a catalytic amount of inorganic phosphate (Pi). When a reaction mixture (10 ml) containing 200 mM sucrose (684 mg), 20 mM Pi, 0.26 U/ml sucrose phosphorylase, 0.034 U/ml xylose isomerase and 0.21 U/ml cellobiose phosphorylase in 50 mM imidazol-HC1 buffer (pH 7.0) was incubated at 37°C, the concentration of cellobiose in the reaction mixture reached 147 mM after 100 hr (yield 73%). Finally, 286 mg of crystalline β-cellobiose was recovered from the reaction mixture by charcoal column chromatography and crystallization.