The present disclosure relates to a method for preparing myo-inositol using myo-inositol monophosphate synthase consisting of an amino acid sequence of SEQ ID NO: 1 and/or myo-inositol monophosphate phosphatase consisting of an amino acid sequence of SEQ ID NO: 3.

Disclosed herein are methods of producing hexoses from saccharides by enzymatic processes. The methods utilize fructose 6-phosphate and at least one enzymatic step to convert it to a hexose.

The current disclosure provides a process for enzymatically converting a saccharide into allulose. The invention also relates to a process for preparing allulose where the process involves converting fructose 6-phosphate (F6P) to allulose 6-phosphate (A6P), catalyzed by allulose 6-phosphate 3-epimerase (A6PE), and converting the A6P to allulose, catalyzed by allulose 6-phosphate phosphatase (A6PP).

The present invention discloses a glucan-based shell-core structure carrier material and preparation and application thereof, and belongs to the technical field of modern food processing. Spherical hyperbranched water-soluble amylum grains are used as the raw material, and an enzymatic grafting and chain extending process is adopted for treatment to modify the surfaces of water-soluble glucan molecules into a firm shell structure with densely cumulated crystal structures, and form the glucan-based carrying material with the shell-core structure of which an inner core cavity has an amorphous state and an outer shell layer has a crystalline state. The adopted spherical hyperbranched water-soluble amylum grains have wide sources of raw materials and are not limited by producing areas and seasons; the preparation has simple and convenient steps, easy operation, controllable reaction conditions, relatively low cost and basically no pollution to the environment; and the prepared product can effectively protect, deliver and release functional nutritional components, can be applied to multiple fields of food, medicine, chemicals for daily use and the like, and has great market prospects and broad economic benefits.

An inositol preparation method by enzymatic catalysis uses starch and cellulose or substrates thereof as substrates. Raw materials are converted to inositol by in vitro multi-enzyme reaction system in one pot. The yield from the substrate to inositol is significantly improved by process optimization and adding new enzymes. The new enzymes can promote the phosphorolysis of starch or cellulose and utilization of glucose, which is the final production after the phosphorolysis of starch and cellulose. The inositol preparation method described herein has great potentials in industrial production of inositol because of high inositol yield, easy scale-up, low production cost, and lower impact to environment

The invention relates to immobilized enzyme compositions for the preparation of a hexose. Hexoses include, for example, tagatose, psicose, fructose, allose, mannose, galactose, altrose, talose, sorbose, gulose, idose, and inositol. The invention also relates to an enzymatic process for preparing a hexose from a saccharide by contacting a starch derivative with an immobilized enzyme composition of the invention.

Provided are a biomimetic silicon mineralized microcapsule immobilized multi-enzyme, a preparation method therefor, and a method for producing tagatose by using same. The preparation method comprises the following steps: (1) pre-mixing glucan phosphorylase, phosphoglucomutase, phosphoglucoisomerase, 6-phosphate tagatose 4-position epimerase and 6-phosphate tagatose phosphatase solutions, then adding the mixture to a calcium chloride solution, and then pouring same into a sodium carbonate solution, stirring and separating same to obtain calcium carbonate microspheres containing a multi-enzyme; (2) mixing the calcium carbonate microspheres with a polyethyleneimine solution to obtain polyethyleneimine-calcium carbonate microspheres after separation; (3) mixing the polyethyleneimine-calcium carbonate microspheres with a silicate solution to obtain biomimetic silicon mineralized-calcium carbonate microspheres after separation; and (4) mixing the biomimetic silicon mineralized-calcium carbonate microspheres with ethylenediamine tetraacetic acid for reaction to remove calcium carbonate, and separating same to obtain a biomimetic silicon mineralized microcapsule immobilized multi-enzyme.

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.

The present disclosure concerns a recombinant yeast host cell exhibiting higher stability and, in some embodiments, higher fermentation performance. The recombinant yeast host cell stability has a limited ability to express an hydrolase during its propagation phase. In return, this limits the cleavage of a yeast cellular component during or after propagation which may be detrimental to the stability and/or fermentation performances. The recombinant yeast host cell expresses a heterologous hydrolase under the control of a heterologous promoter (for limiting the expression of the heterologous hydrolase during propagation and favoring the expression of the heterologous hydrolase during fermentation).

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.