62 results about "Chiro-inositol" patented technology

The invention discloses a method for efficiently synthesizing epiinositol by using a heat-resistant myo-inositol dehydrogenase mutant cascade system, and belongs to the field of biocatalysis engineering. Whole cells for expressing a scyllo-inositol dehydrogenase mutant and a heat-resistant scyllo-inositol dehydrogenase mutant are utilized to catalyze the scyllo-inositol to synthesize the epiinositol in a two-step cascade manner, and different from reported scyllo-inositol and D-chiral inositol synthesis methods, in the process of synthesizing the epiinositol by taking the scyllo-inositol as a substrate, the C4 position of the scyllo-inositol is dehydrogenated firstly, then the C4 position of the scyllo-inositol is dehydrogenated, and the C4 position of the D-chiral inositol According to the present invention, the structure of the substrate and the structure of the product are symmetric, and the enzyme is difficult to specifically recognize during the catalysis process, such that the synthesis of the different chiral compounds of the inositol is the important problem in the biological catalysis field. The invention provides a brand-new way for biocatalytically synthesizing the epiinositol, the yield of the epiinositol is increased to 1.89 g / L through enzyme modification, the conversion rate is 52.6%, and the yield and the conversion rate are the highest level reported publicly at present.

The invention discloses an inositol dehydrogenase mutant and a preparation method of D-chiral inositol, and belongs to the technical field of genetic engineering. The inositol dehydrogenase mutant is obtained by mutating an amino acid sequence as shown in SEQ ID NO.2 through the following mutations: the 200th amino acid is mutated into C from V, the 234th amino acid is mutated into Q from V, and the 256th amino acid is mutated into E from R. According to the invention, the amino acid sequence of wild type inositol dehydrogenase is mutated to obtain the inositol dehydrogenase mutant which is a high-activity mutant capable of catalyzing conversion of myo-inositol into 2-keto-myo-inositol; therefore, when the inositol dehydrogenase mutant and keto isomerase act together to prepare D-chiral inositol by taking myo-inositol as a substrate, the yield of the D-chiral inositol is effectively improved.

The invention discloses an inositol dehydrogenase mutant as well as a preparation method and application thereof, and belongs to the technical field of gene engineering. The inositol dehydrogenase mutant is obtained by mutating an amino acid sequence as shown in SEQ ID NO.1, and the mutation is that the 247th amino acid is mutated from K to R, or the 266th amino acid is mutated from E to D. The inositol dehydrogenase mutant disclosed by the invention has higher enzyme activity, and when the inositol dehydrogenase mutant and ketoisomerase are catalyzed to synthesize D-chiral inositol by taking myo-inositol and NADP < + > as substrates, the reaction is more inclined to a forward reaction, so that the yield of the D-chiral inositol and the conversion rate of the substrate myo-inositol are further improved.

The invention discloses a D-pinitol dehydrogenase MtOEPa mutant and application thereof, and belongs to the technical field of gene engineering. The D-pinitol dehydrogenase MtOEPa mutant is obtained by carrying out any one of the following mutations (A)-(F) on an amino acid sequence shown as SEQ ID NO.1: (A) mutating the 87th amino acid from I into A; (B) the 87th amino acid is mutated from I to A, and the 40th amino acid is mutated from N to A; (C) the 87th amino acid is mutated from I to A, and the 160th amino acid is mutated from P to S; (D) the 87th amino acid is mutated from I to A, and the 200th amino acid is mutated from S to A; (E) the 87th amino acid is mutated from I to A, and the 219th amino acid is mutated from F to Y; (F) the 87th amino acid is mutated into A from I, the 160th amino acid is mutated into S from P, and meanwhile, the 219th amino acid is mutated into Y from F. The stability of the D-pinitol dehydrogenase MtOEPa mutant disclosed by the invention is improved, so that the yield of D-chiro-inositol is improved.

The invention discloses a method for efficiently synthesizing epiinositol by catalyzing muscle inositol through double-enzyme cascade, and belongs to the field of biological catalysis engineering. According to the invention, scyllo-inositol dehydrogenase is mutated to obtain a beneficial mutant C261R, and the beneficial mutant C261R is coupled with heat-resistant myo-inositol dehydrogenase to efficiently catalyze and synthesize the epiinositol, and belongs to the field of biological catalysis engineering. The new way for synthesizing the epiinositol is completely different from reported synthesis methods of scyllo-inositol and D-chiro-inositol, and comprises the following steps of: firstly dehydrogenating the C4 position of the muscle inositol to form an intermediate product ketone, and then hydrogenating to realize chiral inversion of hydrogen at the C4 position, so as to obtain the final product epiinositol. The invention provides a brand new way for biocatalytically synthesizing the epiinositol, the yield of the obtained epiinositol is 1.39 g / L, the conversion rate is 38.7%, the yield and the conversion rate are the highest level which is publically reported at present, the biosynthesis process is simple to operate, low in cost, green and environment-friendly, and a solid research foundation is laid for industrial production of the epiinositol.

The invention discloses a keto isomerase mutant as well as a preparation method and application thereof, and relates to the technical field of gene engineering. The keto isomerase mutant is obtained by performing the following mutations on an amino acid sequence shown as SEQ ID NO.2: the 34th amino acid is mutated from N to R; meanwhile, the 188th amino acid is mutated from I to K. The half-life period of the keto isomerase mutant obtained by mutating the amino acid sequence shown in SEQ ID NO.2 is prolonged, and the enzyme activity is improved, so that the yield of D-chiro-inositol is further improved.

The invention discloses a separation and preparation method of D-chiro-inositol, and relates to the technical field of D-chiro-inositol production, a D-chiro-inositol conversion liquid is subjected to thallus removal, deproteinization, desalination and concentration, then ethanol is added for primary separation, ethanol is added again for crystallization after dealcoholization, D-chiro-inositol is purified, and the D-chiro-inositol is obtained. The ethanol is an inert solvent, more chiral inositol in the solution can be crystallized by adding the ethanol, the yield is increased, after the ethanol is added, the viscosity of a crystallization system is reduced, the flowability of the system is better, the crystal can grow more uniformly during crystallization, the crystal is more uniform, and the purity of the product is improved. And the quality of the D-chiro-inositol is improved.

The invention discloses bovine lactoferrin freeze-dried powder and a preparation method thereof, and belongs to the technical field of protein freeze-drying. The preparation method of the bovine lactoferrin freeze-dried powder comprises the following steps: adding a histidine buffer solution into a bovine lactoferrin solution with the mass concentration of 30-40%, and mixing to obtain a mixed solution; adding a freeze-drying auxiliary material accounting for 0.25-7.0% of the volume of the mixed solution into the mixed solution to obtain a bovine lactoferrin freeze-drying solution; performing spray freezing and freeze drying on the bovine lactoferrin freeze-dried liquid to obtain bovine lactoferrin freeze-dried powder; the freeze-drying auxiliary materials comprise a surfactant, amino acid, D-chiro-inositol and calcium chloride. Compared with the traditional inositol, the D-chiral inositol in the freeze-dried auxiliary material can more effectively replace water molecules, maintain the natural conformation of protein and prevent the bovine lactoferrin structure from collapsing. The calcium chloride in the freeze-drying auxiliary material can stabilize the iron binding area of the bovine lactoferrin in the freeze-drying process, and the biological activity of the bovine lactoferrin after freeze-drying is guaranteed.

The invention discloses a composition containing D-chiro-inositol as well as a preparation method and application of the composition. The composition comprises D-chiro-inositol, Myo-inositol and microcapsule powder, wherein the wall material of the microcapsule powder consists of anhydride modified edible protein and a polysaccharide compound; the edible protein is selected from at least one of spirulina protein, quinoa protein, whey protein and soybean protein; the polysaccharide compound comprises at least one of fucoidin and larch arabinogalactan. Active components are also embedded in the microcapsule powder, and comprise at least one of Omega-3, coenzyme Q10, astaxanthin and vitamin. According to the composition, the stability and bioavailability of fat-soluble active ingredients are improved through microencapsulation, and the composition has a synergistic effect with components such as D-chiro-inositol and Myoinositol, so that insulin resistance is effectively improved, female hormone balance is adjusted, and polycystic ovarian syndrome is improved. The process is simple, is suitable for large-scale production, and can be widely applied to dietary supplements or functional foods.

The invention discloses a mutant and a genetically engineered bacterium for catalytic synthesis of D-chiral inositol by using the mutant, and relates to the technical field of biology, inositol dehydrogenase is subjected to site-directed saturation mutagenesis at N154 and C269 sites and then is subjected to combined mutagenesis at M123, V157, A171 and Y277 to obtain the inositol dehydrogenase mutant, so that a conversion reaction is carried out in a forward direction, and the conversion rate of D-chiral inositol is greatly improved.

The invention relates to an inositol dehydrogenase mutant and application of the inositol dehydrogenase mutant in synthesis of D-chiral inositol. The invention discloses an inositol dehydrogenase mutant, nucleic acid for coding the inositol dehydrogenase mutant, a recombinant expression vector containing the nucleic acid, a recombinant expression transformant containing the recombinant expression vector, and a recombinant inositol dehydrogenase mutant catalyst. The invention also discloses an application of the inositol dehydrogenase mutant or the recombinant inositol dehydrogenase mutant catalyst in catalysis of biotransformation of inositol to synthesize D-chiral inositol. Compared with wild-type inositol dehydrogenase and literature reports, the inositol dehydrogenase disclosed by the invention has the characteristics of high enzyme activity and strong substrate specificity, and has the advantages of mild reaction conditions, small coenzyme addition amount, economy, environmental protection and the like when being used for catalytically preparing D-chiral inositol. Therefore, the inositol dehydrogenase mutant disclosed by the invention has a very good application prospect in actual production of the health care medicine D-chiral inositol.

The invention discloses an enzyme preparation for catalytic synthesis of D-chiro-inositol and a preparation method of D-chiro-inositol, and belongs to the technical field of genetic engineering. The enzyme preparation for catalytic synthesis of D-chiral inositol has enzyme activity for catalyzing the reaction of muscle inositol and NADP < + > to generate D-chiral inositol, and comprises inositol dehydrogenase and keto isomerase, the amino acid sequence of the inositol dehydrogenase is shown as any one of SEQ ID NO.3, SEQ ID NO.4 and SEQ ID NO.5, and the amino acid sequence of the keto isomerase is shown as any one of SEQ ID NO.6, SEQ ID NO.7 and SEQ ID NO.8. The invention further discloses a preparation method of the enzyme preparation for catalytic synthesis of D-chiral inositol. The inositol dehydrogenase and the keto isomerase in the enzyme preparation are mutated on the basis of wild types, so that the enzyme activity of the inositol dehydrogenase and the keto isomerase is improved, and the conversion rate of D-chiral inositol is further improved.

The invention provides a capsule containing supramolecular anti-aging factors and used for improving ovarian functions and a preparation method of the capsule. The capsule is prepared from the following components by weight: 0.4 to 0.8 g of ergothioneine, 5 to 8 g of fruit polyphenol, 10 to 20 g of inositol composition, 5 to 8 g of diindolylmethane, 0.01 to 0.02 g of folic acid and 100 to 200 g of auxiliary materials. High-purity ergothioneine is extracted from pleurotus eryngii through microwave and ultrasonic combination, chiral inositol is extracted from tartary buckwheat seeds, the chiral inositol and myo-inositol are maintained to be in a proper proportion, meanwhile, fruit polyphenol and a small amount of folic acid are used in a matched mode, gelatin and other auxiliary materials are used for preparing a capsule form, the capsule is more convenient to take, the symptoms of premature ovarian failure can be relieved, and the effect of preventing and treating premature ovarian failure is achieved. The raw materials for preparing the capsule are environment-friendly, and the preparation process is simple and suitable for large-scale production.

The invention relates to the technical field of livestock and poultry breeding, in particular to a goat hybridization breeding method capable of achieving complete-cycle nutrition enhancement. The core of the method is that systematic nutrition intervention runs through the whole breeding process. Before hybridization, performing differential nutrition pretreatment on the parents for 60 days: feeding the female parents with a breeding nutrition enhancer added with components such as D-chiro-inositol and N-acetylcysteine, and supplementing sperm motility enhancer containing acetylated L-carnitine and ergothioneine to the male parents. In the gamete treatment stage, the oocytes are subjected to in-vitro maturation culture in a special culture solution containing components such as D-chiro-inositol and a growth differentiation factor 9; after the sperms are subjected to gradient centrifugal screening, completing in-vitro fertilization in an optimized fertilization culture solution; after the embryos develop into blastocysts in the sequential culture system, carrying out laparoscopic transplantation, and carrying out staged precise nutrition culture on the pregnant ewes. According to the method, through multi-level nutrition enhancement, the reproductive capacity of the goats and the growth performance of offspring are effectively improved.

This invention discloses a ketoisomerase mutant and a method for preparing D-chiral inositol, belonging to the field of genetic engineering technology. The ketoisomerase mutant is obtained by mutating the 73rd amino acid of the amino acid sequence shown in SEQ ID NO.3 from L to N. The ketoisomerase mutant L73N obtained by this invention further enhances enzyme activity. When catalyzing the reaction of muscle inositol to synthesize D-chiral inositol together with inositol dehydrogenase, it can further improve the conversion rate and the yield of D-chiral inositol.

This invention discloses a ketoisomerase mutant and its application in the preparation of D-chiral inositol, belonging to the field of genetic engineering technology. The ketoisomerase mutant is obtained by mutating the amino acid sequence shown in SEQ ID NO.1, specifically by mutating amino acid position 62 and / or amino acid position 175 of the amino acid sequence shown in SEQ ID NO.1. After the above-mentioned mutation of the wild-type thermostable ketoisomerase, the resulting ketoisomerase mutant not only retains the advantages of the wild-type thermostable ketoisomerase—its heat resistance and susceptibility to temperature fluctuations—but also exhibits higher enzyme activity. When co-catalyzing the reaction of muscle inositol to D-chiral inositol with inositol dehydrogenase, it can further improve the conversion rate and yield of D-chiral inositol even at high substrate concentrations.

The utility model relates to the technical field of D-chiro-inositol, in particular to a separation and purification system for co-production of glucuronic acid and D-chiro-inositol. Comprising first filtering equipment, second filtering equipment, a cationic resin column, an anionic resin column, first concentration equipment, second concentration equipment, a buffer tank, a first ethanol storage tank, a first filtering device, a first filtrate storage tank, a filter cake storage tank, a second ethanol storage tank, a second filtering device, a second filtrate storage tank and a concentration device which are communicated with a feed liquid conveying pipeline, the device comprises a first drying device, a glucuronic acid storage tank, a second drying device and a D-chiro-inositol storage tank. The separation and purification system is reasonable in design, and compared with existing resin separation, the treatment capacity is large, operation is easy and convenient, and the yield and the separation efficiency are greatly improved.

The application discloses a D-mangiferoline dehydrogenase MtOEPa mutant and application thereof, and belongs to the technical field of genetic engineering. The amino acid sequence of the D-mangiferoline dehydrogenase MtOEPa mutant is shown as SEQ ID NO. 4. The D-mangiferoline dehydrogenase MtOEPa mutant has stronger affinity to a substrate myo-inositol, higher catalytic efficiency and higher enzyme activity, and can significantly improve the conversion rate of a reaction and the yield of D-chiro-inositol when catalyzing the reaction of myo-inositol to generate D-chiro-inositol.

This invention discloses an enzyme preparation and a method for preparing D-chiral inositol, belonging to the field of genetic engineering technology. The enzyme preparation includes inositol dehydrogenase and 2-keto-inositol isomerase. The amino acid sequence of inositol dehydrogenase is shown in SEQ ID NO. 6, and the amino acid sequence of 2-keto-inositol isomerase is shown in SEQ ID NO. 8. Compared with the prior art, the enzyme activities of the inositol dehydrogenase and 2-keto-inositol isomerase with specific amino acid sequences of this invention are further improved. When catalyzing the reaction of muscle inositol to D-chiral inositol, both can further improve the conversion rate and the yield of D-chiral inositol. Furthermore, this inositol dehydrogenase has high tolerance to muscle inositol, and can still efficiently catalyze the reaction to produce D-chiral inositol even at high substrate concentrations, alleviating substrate inhibition.

The present application relates to carbocyclic compounds, more particularly to the field of cyclohexanehexol, and particularly to a method for extracting D-chiro-inositol from Ceratonia siliqua and application thereof. The present application uses an acid hydrolysis method, takes TFA as a catalyst, and takes L-(-) camphor sulfonic acid as a specific recrystallization selection agent to obtain high-purity DCI from Ceratonia siliqua, and has the advantages of high extraction efficiency, high DCI yield, high purity, low cost, green environmental protection and the like.

The application discloses a method for efficiently synthesizing epipolyhydroxymatrine by double-enzyme cascade catalysis of muscle inositol, and belongs to the field of biological catalysis engineering. The application mutates shark inositol dehydrogenase to obtain a beneficial mutant C261R, and couples the mutant with heat-resistant muscle inositol dehydrogenase to efficiently catalyze the synthesis of epipolyhydroxymatrine, and belongs to the field of biological catalysis engineering. The new synthesis method of epipolyhydroxymatrine is completely different from the synthesis methods of shark inositol and D-chiral inositol reported in the prior art. The method is to first dehydrogenate muscle inositol at a C4 position to form an intermediate product ketone, then hydrogenate the intermediate product ketone, realize hydrogen chirality inversion at the C4 position, and obtain the end product epipolyhydroxymatrine. The application provides a brand-new biological catalysis synthesis method of epipolyhydroxymatrine, and the yield of epipolyhydroxymatrine is 1.39 g / L, and the conversion rate is 38.7%, which are the highest levels reported at present. The biological synthesis process is simple in operation, low in cost and green in environmental protection, and lays a solid research foundation for the industrial production of epipolyhydroxymatrine.

The invention discloses a 2-keto-inositol isomerase mutant and application thereof, and belongs to the technical field of gene engineering. The 2-keto-inositol isomerase mutant is obtained by performing at least one of the following mutations on an amino acid sequence as shown in SEQ ID NO.1: (1) mutating the 63rd amino acid from L to A; (2) the 155th amino acid is mutated from E to R; and (3) the 210th amino acid is mutated from G to R. After the wild type 2-keto-inositol isomerase is mutated, the obtained 2-keto-inositol isomerase mutant is higher in enzyme activity, better in heat resistance and longer in half-life period, and when the D-chiral inositol is prepared by combining with inositol dehydrogenase, the reaction conversion rate and the yield of the D-chiral inositol are improved.

The invention relates to the technical field of application of feed additives, and provides d-chiro-inositol serving as a second messenger of insulin, and the d-chiro-inositol serving as an animal feed additive is used for improving animal ingestion and reducing animal blood sugar concentration. D-chiro-inositol is used as an additive in poultry breeding; the additive prepared from the d-chiro-inositol is one of powder, particles, capsules, gel or liquid; the addition amount of the additive in the feed is 3-80mg / kg of the additive; the addition amount of the additive in the feed is 7mg-15mg / kg of the additive; the d-chiro-inositol additive is used for promoting efficient uptake of poultry, and glucose is utilized; the d-chiro-inositol additive is mixed with corn, soybean meal, fish meal, stone powder or shell powder. According to the technical scheme, the problems that animals directly eat common feed at present and cannot eat a certain amount of feed again, glucose digested and taken by the animals is not well utilized, the blood sugar concentration is high, and the animals grow slowly are solved.

The invention discloses a keto isomerase mutant and application thereof, and belongs to the technical field of gene engineering. The keto isomerase mutant is obtained by performing at least one of the following mutations on an amino acid sequence as shown in SEQ ID NO.1: the 64th amino acid is mutated from S to T; and the 105th amino acid is mutated into A from G. According to the invention, after the wild-type ketoisomerase as shown in SEQ ID NO.1 is mutated, the enzyme activity of the obtained ketoisomerase mutant is further improved, so that the yield of D-chiral inositol is further improved.

This invention relates to the field of genetic engineering technology, and particularly to an enzyme preparation for the catalytic synthesis of D-chiral inositol and a method for preparing D-chiral inositol. The enzyme preparation includes inositol dehydrogenase and ketoisomerase. The amino acid sequence of the inositol dehydrogenase is any one of the sequences shown in SEQ ID NO. 23 to SEQ ID NO. 25; the amino acid sequence of the ketoisomerase is any one of the sequences shown in SEQ ID NO. 29 to SEQ ID NO. 31. This invention co-expresses inositol dehydrogenase and ketoisomerase with specific site mutations, significantly improving the conversion rate of D-chiral inositol.

The invention discloses a slow-release nutrition preparation for small needle knife guide in an ovarian reflex region and a preparation method of the slow-release nutrition preparation, and relates to the technical field of medical nutrition preparations. 20 to 30 parts of a slow release carrier; 3-6 parts of an absorption enhancer; 45 to 65 parts of a biocompatible auxiliary material; 1-3 parts of a stabilizer; according to the invention, the D-chiro-inositol is helpful for adjusting hormone balance in vivo and promoting ovarian health; glutathione is a potent antioxidant and protects ovarian cells from oxidative damage; the Q10 coenzyme can enhance cell energy metabolism and improve the ovarian function; soybean isoflavone is phytoestrogen and can simulate the action of estrogen of a human body, the core nutritional ingredients are combined with a slow release carrier prepared from chitosan, sodium alginate and a medicinal fungal polysaccharide compound, slow release of nutrient substances is achieved, action time is prolonged, bioavailability of the nutrient substances is improved, the substances are combined, and the slow release effect is achieved. The nourishing and long-acting protection on the ovary reflex region are realized.

The invention discloses a method for recovering D-chiral inositol mother liquor, and relates to the technical field of D-chiral inositol production.The method comprises the steps that ethyl alcohol is added into the D-chiral inositol mother liquor, and then cooling and suction filtration are conducted to obtain filtrate I and a solid I; adding the solid I into purified water, stirring at 50-60 DEG C for 1-2 hours, concentrating, adding ethanol, cooling, and carrying out suction filtration to obtain filtrate II and a solid II; combining the filtrate I and the filtrate II, distilling, collecting a dealcoholization solution and an ethanol recovery solution, carrying out thermal concentration on the obtained dealcoholization solution until the solid content is 45-55% w / w, adding ethanol into the obtained concentrated solution, cooling, and carrying out suction filtration to obtain a filtrate III and a solid III; and adding purified water into the solid III for dissolving, then adding 1-5% v / v of activated carbon for decoloration, then carrying out suction filtration to obtain a decolorized solution, then adding ethanol, cooling, and carrying out suction filtration to obtain a D-chiro-inositol finished product and a filtrate IV, thereby improving the yield and purity of the product.

The utility model discloses a kind of separation preparation devices of D-chiral inositol, it is related to D-chiral inositol production technical field, the outlet of conversion liquid tank is communicated with ceramic membrane device, the clear liquid outlet of ceramic membrane device is communicated with first concentrator, the outlet of first concentrator is communicated with first crystallizing tank, the outlet of first crystallizing tank is communicated with first filter, the liquid phase outlet of first filter is communicated with dealcoholization tank, the bottom outlet of dealcoholization tank is communicated with second concentrator, the outlet of second concentrator is communicated with second crystallizing tank, the outlet of second crystallizing tank is communicated with second filter, the solid phase outlet of second filter is communicated with D-chiral inositol tank. Through the series connection process of ceramic membrane filtration, twice concentration, twice crystallization and filtration, the step-by-step separation purification of D-chiral inositol is realized, using the selectivity of ethanol crystallization, effectively improve product purity.

The invention relates to the technical field of D-chiro-inositol production, in particular to a process method for preparing D-chiro-inositol by taking kasugamycin hydrochloride as a raw material, which comprises the following steps: taking kasugamycin hydrochloride as a raw material, adding a sulfated zirconium-titanium composite oxide catalyst with SO4 < 2-> loading capacity of 3M, and controlling the reaction temperature and time to prepare D-chiro-inositol. The obtained hydrolysate is filtered, the collected filtrate enters an anion resin column, the obtained effluent is subjected to nanofiltration membrane concentration and vacuum concentration treatment, ethyl alcohol is added into the collected concentrated solution, heat preservation treatment is performed for a period of time, then cooling crystallization is performed, water is added into a D-chiro-inositol crude product collected through suction filtration, stirring and dissolving are performed, then decoloration treatment is performed, and the D-chiro-inositol is obtained. Adding ethanol into the collected decoloring solution, cooling and crystallizing after crystals are separated out, and drying the collected crystals after suction filtration to obtain a D-chiro-inositol product; the process method is simple in process and simple to operate, can obtain the D-chiro-inositol product with high yield and high purity, and is suitable for industrial production.

The invention relates to the technical field of D-chiro-inositol, in particular to a method for recovering D-chiro-inositol mother liquor, which comprises the following steps: respectively collecting D-chiro-inositol secondary crystallization mother liquor and recrystallization mother liquor, adding ethanol into the recrystallization mother liquor, cooling and crystallizing, and collecting a first solid and a first filtrate; merging the secondary crystallization mother liquor and the filtrate, concentrating, decoloring and carrying out suction filtration, concentrating the collected decoloring solution, adding ethanol, cooling, crystallizing and carrying out suction filtration, and respectively collecting a second solid and a second filtrate; mixing the first solid and the second solid, adding water, heating, dissolving, decolorizing, carrying out suction filtration, adding ethanol into the collected decolorized solution, cooling, crystallizing, carrying out suction filtration, and collecting crystals and a third filtrate; and drying the collected crystals to obtain the D-chiro-inositol product. According to the process method, the D-chiro-inositol product with high purity, high content and high yield can be obtained, and resource waste is avoided.