Abstract: A method for preparing immobilized cells for producing mannose, and a method using same for producing mannose, comprising: fermenting to separately obtain fermentation broths of Escherichia coli or Bacillus subtilis expressing a-glucan phosphorylase, phosphoglucomutase, glucose phosphoisomerase, mannose-6-phosphate isomerase and mannose-6-phosphate phosphatase, and mixing the fermentation broths to obtain a mixed fermentation broth.

Abstract: Provided are a Bacillus subtilis genetically engineered bacterium for producing tagatose and a method for preparing tagatose. The genetically engineered bacterium comprises constructing thermostable ?-glucan phosphorylases, thermostable glucose phosphomutases, thermostable glucose phosphate isomerases, thermostable 6-tagatose phosphate epimerases, and thermostable 6-tagatose phosphate phosphatases which are independently expressed or co-expressed. The usage of the genetically engineered bacterium can effectively convert starch into tagatose. Compared with existing methods for producing tagatose, the method has advantages such as suitability for whole-cell recycling, high safety, high yield, simple production process, low cost, and easiness in large-scale preparation.

Abstract: Provided are a preparation method for an immobilized cell for tagatose production and a method for producing tagatose by using the immobilized cell. The preparation method for the immobilized cell comprises: mixing a fermentation broth of Escherichia coli or Bacillus subtilis that expresses ?-glucan phosphorylase, phosphoglucomutase, glucose phosphate isomerase, tagatose 6-phosphate epimerase, and tagatose 6-phosphate phosphatase to obtain a fermentation mixture, adding inorganic soil and then performing uniform stirring, then adding a flocculant to flocculate bacteria, subsequently adding a cross-linking agent to cross-link, performing vacuum filtration to obtain a filter cake, using a rotary granulator to extrude the filter cake to granulate into a long strip, then cutting by means of a spherical shot blasting machine into particles having equal lengths, and performing boiling drying to obtain the immobilized cell for tagatose production.

Abstract: Provided are a biomimetic silicon mineralized microcapsule immobilized multi-enzyme, a preparation method therefor, and a method for producing tagatose by using same.

Abstract: Provided are the immobilization of multiple enzymes on the basis of an artificial oil body and an application thereof in the preparation of tagatose. Specifically, an artificial oil body is used to mix an expressed fusion protein of target protease-oil body protein with an oil body, which then undergoes an ultrasonic treatment; the fusion protein is anchored to the surface of the oil body by means of the specific hydrophobicity of a human protein to form an artificial oil body containing the target protease, so that the purification and immobilization of enzymes can be completed simultaneously. The immobilized multiple enzymes that can be used for tagatose production utilize an artificial oil body as an immobilized enzyme substrate, which significantly improves the stability of the immobilized enzymes, reduces the production cost of the current enzymatic preparation of tagatose, and has a simple preparation process.

Abstract: Provided are a method for preparing an immobilized multi-enzyme system, and a method for producing tagatose by the immobilized multi-enzyme system. The immobilized multi-enzyme system is formed by uniformly mixing a porous dopamine microsphere with a multi-enzyme mixture which is used for producing tagatose. Five enzymes in an enzymatic catalysis path for converting starch to tagatose are co-immobilized by means of a porous microsphere to obtain an immobilized multi-enzyme system, the immobilized multi-enzyme system is used to catalyze conversion of starch into tagatose, and thus, enzymes can be recycled, thereby greatly reducing the amount of enzymes required for preparation of tagatose, and reducing the production cost.