| abstract |
A method for preparing high-purity D-psicose, comprising the following steps: (1) centrifuging a fermentation broth of Bacillus subtilis , and then subjecting the bacteria to homogenization to obtain a mixed solution containing D-psicose 3-epimerase; (2) preparing a fructose solution, adding the mixed solution containing D-psicose 3-epimerase to the fructose solution, adjusting the pH, adding cobalt chloride thereto, and performing the reaction at a certain temperature; and feeding the fructose solution to the reaction solution, continuing the reaction, and stopping the reaction, obtaining a crude D-psicose solution; and (3) subjecting the crude D-psicose solution to decolorization, filtration, ion exchange, chromatographic separation, concentration, and then crystallization or drying, obtaining D-psicose. |