A method for preparing large-particle-size rhombic anhydrous inositol crystals

Abstract

This invention provides a method for preparing large-particle-size rhombic anhydrous inositol crystals. The preparation method includes the following steps: under stirring conditions, a mixed solution of inositol and water at a temperature of 60-80℃ is rapidly cooled to 40-60℃, then an additive is added and maintained for 1-4 hours to obtain the large-particle-size rhombic anhydrous inositol crystals; the additive includes any one or a combination of at least two of L-arabinose, D-xylose, D-glucose, or D-maltose. The crystallization process uses only one raw material and involves only water as the solvent, making it environmentally friendly and simple. The rhombic anhydrous inositol crystals have a highly uniform particle size, with an average particle size of 300-500 micrometers; the product has high flowability, an angle of repose between 34° and 38°, high compressive strength, and can be stored for a long time.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of crystallization technology in chemical engineering industry, and particularly relates to a preparation method of large-particle-size rhombic anhydrous inositol crystals. BACKGROUND

[0002] Inositol, also known as muscle sugar, is a six-carbon ring alcohol with the molecular formula C6H 12 O6, and a sweetness of about 50% of sucrose. Inositol is an essential substance for the growth of humans, animals and microorganisms, and is known as a "growth factor". As a precursor of inositol phosphates and lipids, inositol is involved in various life activities of the body, such as growth regulation, biological membrane formation and signal transduction, and is a necessary nutritional factor for humans.

[0003] In the medical field, inositol can promote fat metabolism in the liver, and is clinically formulated into inositol tablets, inositol nicotinate, triglycerides and other drugs for the treatment of cirrhosis, fatty liver, hepatitis and other diseases. At the same time, inositol can reduce the cholesterol content in the blood and treat fat and cholesterol metabolic disorders. In the food field, inositol is often used as an additive in health foods, premium beverages, dairy products and other foods. More than half of the products in the full-nutrition and infant-specific medical foods have added inositol. Inositol can promote the construction of the cell skeleton of infants and young children and support the normal development of the nervous system and multiple organs of the lungs. In the feed field, inositol is an essential nutrient for aquatic animals and plays an important role in maintaining normal physiological functions. Its application has now expanded to the fields of aquaculture, livestock farming, poultry farming and other industries.

[0004] At present, most of the commercial inositol products are in the form of powder and needles, and the crystal morphology is poor. This leads to low purity of inositol crystals, which seriously affects the sensory quality and powder performance of the product. CN 105669376 B proposes a crystallization process for preparing inositol with high crystallinity and large particle size, 1-5% type I inositol crystal nucleus is added, and the slow cooling rate is between 0.1-3 ℃ / h. The product prepared is columnar inositol crystal, and the particle size can be greater than 100 microns, and the crystallinity is high. However, the aspect ratio of the product is too large, which seriously affects the post-processing process of the product. CN 114181045 A proposes a method for preparing spherical anhydrous inositol using a fluidized bed crystallizer to improve the purity and flowability of inositol products, but this method requires a large amount of crystal seeds (10%) and produces spherical polycrystals, which are easy to break.

[0005] Therefore, finding a preparation method for inositol crystal products that uses very little amount of crystal seeds, greatly improves the particle size of the crystals, improves the crystal morphology, and can be industrialized is still a technical problem that cannot be solved by the prior art. SUMMARY

[0006] In order to overcome the defect of poor crystal morphology of the existing myo-inositol product, the application provides a method for preparing rhombic anhydrous myo-inositol by using an additive, and the prepared rhombic anhydrous myo-inositol crystal has a high uniformity of particle size, and the average particle size is 300-500 microns; the product has high fluidity, the rest angle is between 34-38 degrees, the product has high compressive strength, and can be stored for a long time. Meanwhile, the raw material of the crystallization process is single, and the solvent only involves water, which is green and environmentally friendly, and the process is simple.

[0007] One of the purposes of the application is to provide a preparation method of rhombic anhydrous myo-inositol crystal, which comprises the following steps:

[0008] Under stirring, the myo-inositol-water mixed solution with a temperature of 60-80℃ is rapidly cooled to 40-60℃, and then the additive is added and kept for 1-4h to obtain the large-particle-size rhombic anhydrous myo-inositol crystal; in the cooling process, the temperature is reduced by 20-30℃.

[0009] The additive comprises any one or a combination of at least two of L-arabinose, D-xylose, D-glucose or D-maltose.

[0010] Preferably, the concentration of myo-inositol in the myo-inositol-water mixed solution is 0.2-0.5g / mL.

[0011] Preferably, the cooling rate is 4-5℃ / min.

[0012] Preferably, the additive is added in an amount of 1-20g based on 100g of the myo-inositol-water solution.

[0013] Preferably, the stirring rate is 100-300rpm;

[0014] Preferably, the flow field of the stirring is formed by anchor paddle or flat angle paddle stirring.

[0015] Preferably, the preparation method further comprises sequentially performing solid-liquid separation, washing and drying on the mixed solution obtained after keeping for 1-4h;

[0016] Preferably, the solid-liquid separation is performed by suction filtration.

[0017] Preferably, the drying temperature is 40-60℃, and the drying time is 4-8h.

[0018] The second purpose of the application is to prepare the large-particle-size rhombic anhydrous myo-inositol crystal by using the preparation method according to the first purpose.

[0019] Preferably, the average particle size of the large-particle-size rhombic anhydrous myo-inositol crystal is 300-500 microns.

[0020] Preferably, the large-particle-size rhombic anhydrous inositol crystals have a rest angle of 34-38°.

[0021] Preferably, the large-particle-size rhombic anhydrous inositol crystals have a purity of 100%.

[0022] The third object of the present application is the large-particle-size rhombic anhydrous inositol crystals according to the second object for use in any one of a drug, a food or a feed additive.

[0023] Technical features and advantages of the present application:

[0024] 1. The present method effectively improves the morphology of inositol crystals by adding additives, and inhibits the growth of dominant crystal faces through hydrogen bond interaction, thereby preparing rhombic anhydrous inositol crystals.

[0025] 2. The rhombic anhydrous inositol crystals prepared by the present method have an average particle size of 300-500 μm, high purity, and good flow performance, which provides excellent conditions for the subsequent processing of inositol products, and can reduce costs and improve production efficiency.

[0026] 3. The present method uses only water as a solvent, has single raw materials, is green and environmentally friendly, has a simple process, can be industrialized, and has low economic investment. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 : Optical microscope picture of anhydrous inositol raw material;

[0028] Figure 2 : Optical microscope picture of rhombic anhydrous inositol crystals;

[0029] Figure 3 : XRD pattern of anhydrous inositol raw material and rhombic anhydrous inositol crystals;

[0030] Figure 4 : High-performance liquid chromatogram of rhombic anhydrous inositol crystals;

[0031] Figure 5 : Particle size distribution of rhombic anhydrous inositol product of Example 1; DETAILED DESCRIPTION

[0032] Example 1:

[0033] (1) Prepare a mixed solution of inositol-water with a concentration of 0.2 g / mL at 60°C.

[0034] (2) The solution is rapidly cooled to 40°C at a rate of 4°C / min, 1% L-arabinose additive is added, and stirring is maintained at 300 rpm for 1 h to allow the crystals to crystallize and precipitate.

[0035] (3) filtration, washing, drying at 40℃ for 8h, to obtain rhombic anhydrous inositol crystals.

[0036] The optical microscope picture of the rhombic anhydrous inositol crystals is shown in Figure 2 Compared with the anhydrous inositol raw material, Figure 1 , the crystal morphology is greatly improved. The XRD spectra of the anhydrous inositol raw material and the rhombic anhydrous inositol crystals are shown in Figure 3 , and the XRD spectra of the two are consistent, indicating that the prepared rhombic inositol crystals are anhydrous inositol crystal form. The high performance liquid chromatograph purity test results are shown in Figure 4 , the purity of the rhombic anhydrous inositol crystals in Example 1 is 100%. The particle size distribution of the rhombic anhydrous inositol crystals in Example 1 is shown in Figure 5 , the average particle size is 355um, and the rest angle is 34°.

[0037] Example 2:

[0038] (1) Prepare an inositol-water mixed solution with an inositol concentration of 0.3g / mL at 70℃.

[0039] (2) The solution is rapidly cooled to 50℃ at a rate of 4℃ / min, 5% D-xylose additive is added, and stirring is maintained at 200rpm for 2h to allow the crystals to crystallize and precipitate.

[0040] (3) filtration, washing, drying at 50℃ for 6h, to obtain rhombic anhydrous inositol crystals.

[0041] The rhombic anhydrous inositol crystals obtained in this example are tested by the same method as in Example 1, and it is found that the rhombic inositol crystals obtained are anhydrous inositol crystal form, the purity is 100%, the average particle size is 395um, and the rest angle is 35°.

[0042] Example 3:

[0043] (1) Prepare an inositol-water mixed solution with an inositol concentration of 0.4g / mL at 80℃.

[0044] (2) The solution is rapidly cooled to 60℃ at a rate of 5℃ / min, 10% D-glucose additive is added, and stirring is maintained at 150rpm for 3h to allow the crystals to crystallize and precipitate.

[0045] (3) filtration, washing, drying at 50℃ for 6h, to obtain rhombic anhydrous inositol crystals.

[0046] The rhombic anhydrous inositol crystals obtained in this example are tested by the same method as in Example 1, and it is found that the rhombic inositol crystals obtained are anhydrous inositol crystal form, the purity is 100%, the average particle size is 445um, and the rest angle is 36°.

[0047] Example 4:

[0048] (1) At 80°C, prepare a myo-inositol-water mixed solution with a myo-inositol concentration of 0.5 g / mL.

[0049] (2) Rapidly cool the solution to 60°C at a rate of 5°C / min, add 20% D-maltose additive, maintain stirring at 100 rpm for 4 h, and allow the crystals to crystallize and precipitate.

[0050] (3) Filter, wash, and dry at 40°C for 8 h to obtain rhombic anhydrous myo-inositol crystals.

[0051] The rhombic anhydrous myo-inositol crystals obtained in this example were tested using the same method as in Example 1, and it was found that the rhombic myo-inositol crystals obtained were anhydrous myo-inositol crystals, with a purity of 100%, an average particle size of 486 um, and a rest angle of 38°.

[0052] Comparative Example 1

[0053] The only difference from Example 1 is that 0.1% L-arabinose additive was added in step (2), and the remaining preparation methods were the same as in Example 1.

[0054] No rhombic anhydrous myo-inositol crystals were obtained in this comparative example, and the crystal morphology was long needle-shaped.

[0055] As shown by comparing Example 1 and Comparative Example 1, when the amount of additive added is less than the limited range of the present application, the hydrogen bonding between groups is weak, the crystal morphology is long needle-shaped, and rhombic anhydrous myo-inositol crystals cannot be formed.

[0056] Comparative Example 2

[0057] The only difference from Example 1 is that 30% L-arabinose additive was added in step (2), and the remaining preparation methods were the same as in Example 1.

[0058] No rhombic anhydrous myo-inositol crystals were obtained in this comparative example, and the crystal morphology was long needle-shaped.

[0059] As shown by comparing Example 1 and Comparative Example 2, when the amount of additive added exceeds the limited range of the present application, the solution system is sticky, forming a sticky paste shape, and the myo-inositol crystal morphology is long needle-shaped.

[0060] Comparative Example 3

[0061] The only difference from Example 1 is that the stirring rate in step (2) was 500 rpm, and the remaining preparation methods were the same as in Example 1.

[0062] No rhombic anhydrous myo-inositol crystals were obtained in this comparative example, and the crystal morphology was long needle-shaped, and the crystals were severely broken.

[0063] By comparing Example 1 and Comparative Example 3, it can be seen that when the stirring rate exceeds the limit of the present invention, the collision between crystals will be intensified, resulting in crystal breakage and seriously affecting the morphology of inositol crystals.

[0064] Comparative Example 4:

[0065] The difference from Example 1 is that L-arabinose is replaced with D-fructose, while the rest of the preparation method is the same as in Example 1.

[0066] This comparative example did not yield rhomboid anhydrous inositol crystals; the product morphology was long needle-like.

[0067] By comparing Example 1 and Comparative Example 4, it can be seen that when the types of additives exceed the limits of the present invention, rhomboid anhydrous inositol crystals cannot be obtained.

[0068] Comparative Example 5:

[0069] The difference from Example 1 is that L-arabinose is replaced with alanine, while the rest of the preparation method is the same as in Example 1.

[0070] This comparative example did not yield rhomboid anhydrous inositol crystals; the product morphology was long needle-like.

[0071] By comparing Example 1 and Comparative Example 5, it can be seen that when the types of additives exceed the limits of the present invention, rhomboid anhydrous inositol crystals cannot be obtained.

[0072] Comparative Example 6

[0073] The only difference from Example 3 is that the temperature is lowered to 70°C; the rest of the preparation method is the same as in Example 3.

[0074] In this comparative example, the solution remained clear throughout, and no rhombic anhydrous inositol crystals were obtained.

[0075] By comparing Example 1 and Comparative Example 5, it can be seen that when the cooling range is lower than the limit range of the present invention, the supersaturation of the mixed solution is too low, and no crystals are formed.

[0076] Comparative Example 7

[0077] The only difference from Example 3 is that the temperature is lowered to 30°C; the rest of the preparation method is the same as in Example 3.

[0078] This comparative example yielded a mixture of rhomboid anhydrous inositol crystals and long needle-shaped anhydrous inositol crystals.

[0079] By comparing Example 1 and Comparative Example 6, it can be seen that when the cooling range is higher than the limit of the present invention, the supersaturation of the mixed solution will be too high, resulting in a large number of needle-like crystals and affecting the quality of the product.

[0080] This invention discloses and proposes a method for preparing large-particle-size rhombic anhydrous inositol crystals. Those skilled in the art can implement this method by appropriately changing the temperature of the mixed solution, the concentration of inositol, the type and amount of additives, the stirring rate, etc., based on the content of this document. The method of this invention has been described through preferred embodiments. Those skilled in the art can obviously modify or appropriately change and combine the methods and products described herein without departing from the content, spirit, and scope of this invention to achieve the technical results of this invention. It should be particularly noted that all similar substitutions and modifications are obvious to those skilled in the art and are considered to be included within the spirit, scope, and content of this invention.

Claims

1. A process for the preparation of large particle size rhombic anhydrous inositol crystals, characterized by, The preparation method comprises the following steps: The inositol-water mixed solution with a temperature of 60-80℃ is rapidly cooled to 40-60℃ under stirring, and then the additive is added and kept for 1-4 hours to obtain the large-size rhombic anhydrous inositol crystals; The additive comprises any one or a combination of at least two of L-arabinose, D-xylose, D-glucose or D-maltose; The additive is added in an amount of 1-20g based on 100g of the inositol-water solution; The cooling rate is 4-5℃ / min; The stirring rate is 100-300rpm.

2. The production method according to claim 1, characterized by, The concentration of inositol in the inositol-water mixed solution is 0.2-0.5g / mL.

3. The preparation method according to claim 1, characterized in that, The flow field of the stirring is formed by anchor-shaped paddles or flat-angle paddles.

4. The method of claim 1, wherein, The preparation method further comprises sequentially performing solid-liquid separation, washing and drying on the mixed solution obtained after being kept for 1-4 hours.

5. The production method according to claim 4, characterized by, The solid-liquid separation is performed by suction filtration.

6. The preparation method according to claim 4, characterized in that, The drying temperature is 40-60℃, and the drying time is 4-8h.

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