Method for detecting ratio of chiral inositol to inositol

Abstract

The invention discloses a method for detecting the ratio of chiral inositol to inositol, and relates to the technical field of chiral inositol content detection.The method comprises the steps that chiral inositol, inositol and water are dissolved, at least five standard substance solutions with different ratios of chiral inositol to inositol and the same baume degree are prepared, and the value of the baume degree of each standard substance solution is recorded as Beb; determining the optical rotation of each standard substance solution; drawing a standard curve by taking the ratio of the chiral inositol to the inositol as a horizontal coordinate and the optical rotation of the corresponding standard substance solution as a vertical coordinate; the baume degree and the optical rotation of the sample solution are measured, the value of the baume degree of the sample solution is recorded as BeY, and the value of the optical rotation of the sample solution is recorded as A; when BeY is not equal to Beb, calculating the optical rotation B of the sample solution when the baume degree is Beb according to a formula I; formula I; substituting the optical rotation B into the standard curve to calculate the ratio of chiral inositol to inositol; the method is simple and fast, and has good accuracy.

Description

Technical Field

[0001] This invention relates to the field of chiral inositol content detection technology, and in particular to a method for detecting the ratio of chiral inositol to inositol. Background Technology

[0002] D-chiro-inositol (DCI) is one of the nine isomers of inositol that is optically active. Recent studies have revealed that, in addition to its role in promoting hepatic lipid metabolism, DCI also possesses unique physiological functions such as insulin sensitization, blood sugar reduction, improvement of ovulation in patients with polycystic ovary syndrome (PCOS), regulation of hormone balance, improvement of menstrual disorders, and antioxidant, anti-aging, and anti-inflammatory effects.

[0003] In one biotransformation pathway, D-chiral inositol can be generated from inositol through enzymatic catalysis. In industrial production, it is necessary to use liquid chromatography to detect the content of D-chiral inositol in a timely manner, so as to check the material conversion status and determine whether the process can continue. This not only consumes time, but also requires liquid chromatography detection instruments, making production inseparable from the "eyes" of detection.

[0004] Therefore, there is an urgent need to establish a simple and rapid quantitative analysis method for determining the content of chiral inositol in the feed solution. Summary of the Invention

[0005] The purpose of this invention is to provide a method for detecting the ratio of chiral inositol to inositol, which is simple, fast, and has good accuracy.

[0006] To achieve the above objectives, a first aspect of the present invention provides a method for detecting the ratio of chiral inositol to inositol, wherein the method includes: Chiral inositol, inositol, and water were dissolved to prepare at least five standard solutions with different ratios of chiral inositol to inositol and the same Baume degree. The Baume degree value of the standard solution is denoted as Be. b‌ ; Determine the optical rotation of each standard solution; A standard curve was plotted with the ratio of chiral inositol to inositol on the x-axis and the optical rotation of the corresponding standard solution on the y-axis. The Baumé degree and optical rotation of the sample solution are determined, and the Baumé degree of the sample solution is denoted as Be. Y‌ The optical rotation value of the sample solution is denoted as A; When Be Y =Be b‌ When the optical rotation of the sample solution is substituted into the standard curve, the ratio of chiral inositol to inositol is calculated. When Be Y ≠Beb When, according to Formula I, the sample solution at a Baume degree of Be is calculated. b Optical rotation B at that time; Formula I; Substitute the optical rotation B into the standard curve to calculate the ratio of chiral inositol to inositol.

[0007] Compared with existing technologies, this invention measures the optical rotation of chiral inositol and inositol at different ratios, and plots a standard curve with the mass ratio of chiral inositol to inositol in the standard solution as the x-axis and the corresponding optical rotation of the standard solution as the y-axis; when measuring the Baume degree Be of the sample solution... b Baume degree (Be) of the standard solution b Similarly, by measuring the optical rotation of the sample solution and substituting it into the standard curve, the ratio of chiral inositol to inositol in the sample solution can be directly measured.

[0008] The detection method of this invention eliminates the need for dilution and / or concentration of the sample solution, thereby improving detection efficiency. When measuring the Baume degree (Be) of the sample solution... b Baume degree (Be) of the standard solution b At different times, the sample solution at a Baumé degree of Be is calculated using Formula I. b The optical rotation B at that time can be used to directly determine the ratio of chiral inositol to inositol in the sample solution by substituting it into the standard curve. The method of this invention is simple, rapid, saves detection time, and has good accuracy.

[0009] In addition, the detection method of the present invention is for the production liquid in which inositol is catalyzed by enzymes to generate D-chiral inositol, which can save the detection cost of liquid phase. Conventional polarimeter equipment has a small footprint, low price, and is easy to operate, making it convenient for front-line production personnel to conduct detection themselves, thereby reducing the production cost of chiral inositol.

[0010] Furthermore, the Baume degree of the standard solution is 5-10%.

[0011] In this invention, when the Baumé degree of the standard solution meets the above-mentioned range, the measured optical rotation data is more accurate, which is beneficial to improving the accuracy of the detection method.

[0012] Furthermore, the chiral inositol content is 10-90% based on the total mass of chiral inositol and inositol in the standard solution.

[0013] Furthermore, the Baumé degree of the sample solution is 5-10%.

[0014] In this invention, when the Baumé degree of the sample solution meets the above-mentioned range, the measured optical rotation data is more accurate, which is beneficial to improving the accuracy of the detection method.

[0015] Furthermore, when determining the optical rotation of each standard solution, the temperature of each standard solution is the same, denoted as Tb; Tb is 20℃ to 25℃.

[0016] Furthermore, when determining the optical rotation of the sample solution, the temperature of the sample solution is Ti; Ti is 20°C to 40°C.

[0017] Furthermore, when Be Y =Be b When Ti = Tb, the optical rotation A of the sample solution is substituted into the standard curve to calculate the ratio of chiral inositol to inositol.

[0018] Furthermore, when Be Y =Be b And Ti≠Tb ‌ Then, calculate the optical rotation A of the sample solution at temperature Tb according to Formula II. Tb , A Tb =A Ti -[-0.00075×(Ti-Tb)] Formula II; Among them, A Tb It is the optical rotation value of the sample solution at temperature Tb, -0.00075 is the temperature coefficient, and A Ti It is the optical rotation value of the sample solution at a temperature of Ti; Optical rotation A Tb Substitute the values ​​into the standard curve to calculate the ratio of chiral inositol to inositol.

[0019] In this invention, when Be Y =Be b And Ti≠Tb ‌ At that time, the optical rotation A of the sample solution at temperature Tb is calculated using Formula II. Tb Then the optical rotation A Tb The ratio of chiral inositol to inositol is calculated by substituting the values ​​into the standard curve, thereby further improving detection efficiency while also ensuring detection accuracy.

[0020] Furthermore, when Be Y ≠Be b And Ti≠Tb ‌ Then, calculate the optical rotation A of the sample solution at temperature Tb according to Formula II. Tb Optical rotation A Tb Substituting into Formula I, the sample solution at a Baume degree of Be is calculated. b The optical rotation B at that time is used to calculate the ratio of chiral inositol to inositol by substituting the optical rotation B into the standard curve.

[0021] In this invention, when Be Y ≠Beb And Ti≠Tb ‌ First, calculate the optical rotation A of the sample solution at temperature Tb using Formula II. Tb Then, the sample solution at a Baume degree of Be is calculated using Formula I. b The optical rotation B at that time is used to calculate the ratio of chiral inositol to inositol, thereby further improving detection efficiency while taking into account detection accuracy.

[0022] Furthermore, the sample solution is a production feed solution for the enzymatic conversion of inositol into D-chiral inositol. Attached Figure Description

[0023] The accompanying drawings, which are provided to further illustrate the invention and constitute a part of this invention, are illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention.

[0024] In the attached diagram: Figure 1 This is the standard curve graph of Example 1. Detailed Implementation

[0025] To make the technical problems, technical solutions, and beneficial effects of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0026] The first aspect of the present invention provides a method for detecting the ratio of chiral inositol to inositol, wherein the method includes: Chiral inositol, inositol, and water were dissolved to prepare at least five standard solutions with different ratios of chiral inositol to inositol and the same Baume degree. The Baume degree value of the standard solution is denoted as Be. b‌ ; Determine the optical rotation of each standard solution; A standard curve was plotted with the ratio of chiral inositol to inositol on the x-axis and the optical rotation of the corresponding standard solution on the y-axis. The Baumé degree and optical rotation of the sample solution are determined, and the Baumé degree of the sample solution is denoted as Be. Y‌ The optical rotation value of the sample solution is denoted as A; When Be Y =Be b‌ When the optical rotation of the sample solution is substituted into the standard curve, the ratio of chiral inositol to inositol is calculated. When Be Y ≠Be b When, according to Formula I, the sample solution at a Baume degree of Be is calculated. b Optical rotation B at that time; Formula I; Substitute the optical rotation B into the standard curve to calculate the ratio of chiral inositol to inositol.

[0027] Using the above technical solution, a standard curve was plotted by measuring the optical rotation of chiral inositol and inositol at different ratios, with the mass ratio of chiral inositol to inositol in the standard solution as the abscissa and the corresponding optical rotation of the standard solution as the ordinate. When measuring the Baume degree (Be) of the sample solution... b Baume degree (Be) of the standard solution b Similarly, by measuring the optical rotation of the sample solution and substituting it into the standard curve, the ratio of chiral inositol to inositol in the sample solution can be directly measured.

[0028] The detection method of this invention eliminates the need for dilution and / or concentration of the sample solution, thereby improving detection efficiency. When measuring the Baume degree (Be) of the sample solution... b Baume degree (Be) of the standard solution b At different times, the sample solution at a Baumé degree of Be is calculated using Formula I. b The optical rotation B at that time can be used to directly determine the ratio of chiral inositol to inositol in the sample solution by substituting it into the standard curve. The method of this invention is simple, rapid, saves detection time, and has good accuracy.

[0029] In addition, the detection method of the present invention is for the production liquid in which inositol is catalyzed by enzymes to generate D-chiral inositol, which can save the detection cost of liquid phase. Conventional polarimeter equipment has a small footprint, low price, and is easy to operate, making it convenient for front-line production personnel to conduct detection themselves, thereby reducing the production cost of chiral inositol.

[0030] In some embodiments, the chiral inositol is D-chiral inositol.

[0031] In some embodiments, the Baume degree of the standard solution is 5-10%.

[0032] By adopting the above technical solution, when the Baumé degree of the standard solution meets the above range, the measured optical rotation data is more accurate, which is beneficial to improving the accuracy of the detection method.

[0033] For example, the Baumé degree of the standard solution may be 5%, 6%, 7%, 8%, 9%, or 10%, or a range consisting of any two of the above values.

[0034] Preferably, the Baume degree of the standard solution is 5-8%.

[0035] In some embodiments, the chiral inositol content is 10-90% based on the total mass of chiral inositol and inositol in the standard solution.

[0036] Using the above technical solution, those skilled in the art can select the chiral inositol content in the standard solution by estimating the chiral inositol content in the sample solution. It is understood that the chiral inositol content, the chiral inositol ratio, or the percentage of chiral inositol in the standard solution all refer to the mass fraction of chiral inositol based on the total mass of chiral inositol and inositol in the standard solution.

[0037] In some embodiments, the Baume degree of the sample solution is 5-10%.

[0038] Using the above technical solution, when the Baumé degree of the sample solution meets the aforementioned range, the measured optical rotation data is more accurate, which is beneficial to improving the accuracy of the detection method. It is understood that when the Baumé degree of the sample solution is greater than 10%, it can be diluted with water to achieve a Baumé degree of 5-10%. When the Baumé degree of the sample solution is less than 5%, it can be concentrated under conditions of 60-80℃ and a vacuum degree of -0.085MPa to -0.1MPa to achieve a Baumé degree of 5-10%.

[0039] Preferably, the Baumé degree of the sample solution is 5-8%.

[0040] In some embodiments, when measuring the optical rotation of each standard solution, the temperature of each standard solution is the same, denoted as Tb; Tb is 20°C to 25°C.

[0041] In some embodiments, when determining the optical rotation of the sample solution, the temperature of the sample solution is Ti; Ti is 20°C to 40°C.

[0042] Preferably, Ti is between 20°C and 30°C.

[0043] In some embodiments, when Be Y =Be b When Ti = Tb, the optical rotation A of the sample solution is substituted into the standard curve to calculate the ratio of chiral inositol to inositol.

[0044] In some embodiments, when Be Y =Be b And Ti≠Tb ‌ Then, calculate the optical rotation A of the sample solution at temperature Tb according to Formula II. Tb , A Tb =A Ti -[-0.00075×(Ti-Tb)] Formula II; Among them, A Tb It is the optical rotation value of the sample solution at temperature Tb, -0.00075 is the temperature coefficient, and A TiIt is the optical rotation value of the sample solution at a temperature of Ti; Optical rotation A Tb Substitute the values ​​into the standard curve to calculate the ratio of chiral inositol to inositol.

[0045] Using the above technical solution, when Be Y =Be b And Ti≠Tb ‌ At that time, the optical rotation A of the sample solution at temperature Tb is calculated using Formula II. Tb Then the optical rotation A Tb The ratio of chiral inositol to inositol is calculated by substituting the values ​​into the standard curve, thereby further improving detection efficiency while also ensuring detection accuracy.

[0046] In some embodiments, when Be Y ≠Be b And Ti≠Tb ‌ Then, calculate the optical rotation A of the sample solution at temperature Tb according to Formula II. Tb Optical rotation A Tb Substituting into Formula I, the sample solution at a Baume degree of Be is calculated. b The optical rotation B at that time is used to calculate the ratio of chiral inositol to inositol by substituting the optical rotation B into the standard curve.

[0047] Using the above technical solution, when Be Y ≠Be b And Ti≠Tb ‌ First, calculate the optical rotation A of the sample solution at temperature Tb using Formula II. Tb Then, the sample solution at a Baume degree of Be is calculated using Formula I. b The optical rotation B at that time is used to calculate the ratio of chiral inositol to inositol, thereby further improving detection efficiency while taking into account detection accuracy.

[0048] In some embodiments, the sample solution is a production feed solution for the enzymatic conversion of inositol to D-chiral inositol.

[0049] In some embodiments, the optical rotation of the standard solution is measured three or more times, and the average value is taken as the optical rotation of the standard solution.

[0050] To better illustrate the technical solution of the present invention, the following specific embodiments are also provided.

[0051] Unless otherwise specified, all raw materials used in the examples and comparative examples were obtained commercially.

[0052] Example 1 - Establishing a Standard Curve S1. Accurately weigh inositol (MI) and D-chiral inositol (DCI) according to Table 1, and label them in order to obtain standard 1 to standard 5. Table 1 S2. Accurately measure 50 mL of double-distilled water and completely dissolve the above standards 1-5 to obtain the Baume degree Be. b‌ 1-5 is a 5% standard solution; S3. Turn on the automatic polarimeter and preheat for 30 minutes; select optical rotation and test tube length 100 mm; maintain the temperature at 25℃ and calibrate with water to 0°; rinse the test tubes 3 times with the prepared solution; pour standard solutions 1-5 into the test tubes respectively, add the sample to 1 / 3 of the way from the mouth of the test tube, and ensure there are no air bubbles in the test tube; place the test tubes containing the standard solutions in a water bath to preheat the standard solution temperature to 25℃; S4. Place the test tube in the sample measurement optical path of the instrument. After the data stabilizes, record the optical rotation data. Repeat the measurement three times for each standard solution. Calculate the average optical rotation of each standard solution. The test results are shown in Table 2. Plot a standard curve with the proportion of chiral inositol in the standard solutions as the x-axis and the corresponding optical rotation of the standard solutions as the y-axis. The standard curve is shown below. Figure 1 As shown.

[0053] Table 2 Example 2 S1. According to the chiral inositol ratio in Table 3, accurately weigh the inositol (MI) and D-chiral inositol (DCI) to prepare 20 sample solutions with different gradient chiral inositol ratios, denoted as sample solutions 1-20. S2. Measure the Baumé degree of the sample solution and record the Baumé degree data Be. Y‌ ; S3. Turn on the automatic polarimeter and preheat for 30 minutes; select optical rotation and test tube length 100 mm; maintain the temperature at 25℃ and calibrate with water to 0°; rinse the test tubes three times with the prepared solution; pour the sample solution into the test tubes, filling the sample to 1 / 3 of the way from the mouth of the test tube, ensuring there are no air bubbles in the test tube; place the test tubes containing the sample solution in a water bath to preheat the sample solution temperature to 25℃; S4. Calculate the average optical rotation A of each sample solution, when Be... Y =Be b‌ When the optical rotation A of the sample solution is substituted into the standard curve in Example 1, the ratio of chiral inositol to inositol is calculated; when Be Y ≠Be b When, according to Formula I, the sample solution at a Baume degree of Be is calculated. bAfter determining the optical rotation B, the optical rotation B was substituted into the standard curve to calculate the ratio of chiral inositol to inositol. The test results are shown in Table 3. Formula I; Wherein, the optical rotation B is the sample solution at a Baumé degree of Be. b The optical rotation value at a time; A is the sample solution at a Baumé degree of Be. Y‌ Optical rotation value at time; Be Y‌ The Baumé degree of the sample solution; Be b‌ This refers to the Baumé degree of the standard solution.

[0054] The proportion of chiral inositol in sample solutions (1-20) was determined by liquid chromatography. The liquid chromatography method included: testing D-chiral inositol standards with different proportions using the external standard method and plotting a standard curve; calculating the DCI content in the sample based on the peak area; and using a Waters NH2 column (250×4.6 mm, 5 μm); a mobile phase of 80% acetonitrile and 20% water; a flow rate of 1 mL / min; an injection volume of 10 μl; signal collection using a RID detector; and a column and detector temperature of 35 °C.

[0055] The test results are shown in Table 3.

[0056] Table 3 Example 3 S1. According to the chiral inositol ratio in Table 4, accurately weigh the inositol (MI) and D-chiral inositol (DCI) to prepare 5 groups of sample solutions with a Baume degree of 5% and different gradients of chiral inositol ratio, and denoted as sample solutions 21-25. S2. Turn on the automatic polarimeter and preheat for 30 minutes; select optical rotation as the parameter and 100 mm as the test tube length; maintain the temperature at 25°C and calibrate to 0°C with water; rinse the test tubes three times with the prepared solution; pour the sample solution into the test tubes, filling the sample to 1 / 3 of the way from the mouth of the test tube, ensuring there are no air bubbles in the test tube; record the temperature of the sample solution as Ti, and in Example 1, the temperature Tb of the standard solution when measuring optical rotation is 25°C; S3. Calculate the average optical rotation A of each sample solution. Ti The optical rotation A of the sample solution at temperature Tb is calculated according to Formula II. Tb , A Tb =A Ti -[-0.00075×(Ti-Tb)] Formula II; Among them, A Tb It is the optical rotation value of the sample solution at temperature Tb, -0.00075 is the temperature coefficient, and A TiIt is the optical rotation value of the sample solution at temperature Ti; the optical rotation A Tb Substitute the values ​​into the standard curve to calculate the ratio of chiral inositol to inositol. The test results are shown in Table 4.

[0057] Table 4 Example 4 The sample solution in Example 4 is a production feed solution for the enzymatic conversion of inositol to D-chiral inositol, specifically comprising: Production feed solution 1: Conversion solution, a reaction mixture obtained after inositol undergoes stereoselective conversion under the action of a specific enzyme, inositol dehydrogenase; Production feed liquid 2: Ceramic membrane clear liquid, the permeate after the conversion liquid is filtered through the ceramic membrane; Production feed liquid 3: Ultrafiltration clear liquid, the filtrate after the ceramic membrane clear liquid has been treated by ultrafiltration membrane; Production feed liquid 4: Desalination and decolorization liquid, ultrafiltration clear liquid passes through cation exchange resin D67, the resulting effluent passes through decolorization resin 109D, and the resulting effluent passes through anion exchange resin LS4539. Production feed liquid 5: Nanofiltration concentrate, which is the concentrate formed after the desalination and decolorization liquid is concentrated through a nanofiltration (NF) membrane.

[0058] Test method: S1. Dilute the production liquid 1-5 with water to a Baume degree of 5-10%, or concentrate it to a Baume degree of 5-10% under conditions of 70℃ and vacuum degree of -0.095MPa; S2. Sequentially measure the Baume degree of production feed solutions 1-5 and record the Baume degree data Be. Y‌ ; S3. Turn on the automatic polarimeter and preheat for 30 minutes; select optical rotation and test tube length 100 mm; maintain the temperature at 25℃ and calibrate with water to 0°; rinse the test tubes 3 times with the prepared solution; pour the production solution into the test tubes respectively, fill the sample to 1 / 3 of the test tube opening, and ensure there are no air bubbles in the test tube; place the test tubes containing the production solution in a water bath to preheat the production solution temperature to 25℃; S4. Calculate the average optical rotation A of each production feed liquid, when Be Y =Be b‌ When the optical rotation A of the production solution is substituted into the standard curve in Example 1, the ratio of chiral inositol to inositol is calculated; when Be Y ≠Be b At that time, the production feed liquid is calculated according to Formula I at a Baume degree of Be. b After determining the optical rotation B, the optical rotation B was substituted into the standard curve to calculate the ratio of chiral inositol to inositol. The test results are shown in Table 5. The proportion of chiral inositol in the production feed liquid was detected by liquid chromatography, and the test method was the same as that in Example 2.

[0059] Table 5 The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for detecting the ratio of chiral inositol to inositol, characterized in that, The method includes: Chiral inositol, inositol, and water were dissolved to prepare at least five standard solutions with different ratios of chiral inositol to inositol and the same Baume degree. The Baume degree value of the standard solution is denoted as Be. b‌ ; Determine the optical rotation of each standard solution; A standard curve was plotted with the ratio of chiral inositol to inositol in the standard solution as the x-axis and the optical rotation of the corresponding standard solution as the y-axis. The Baumé degree and optical rotation of the sample solution are determined, and the Baumé degree of the sample solution is denoted as Be. Y‌ The optical rotation value of the sample solution is denoted as A; When Be Y =Be b‌ When the optical rotation of the sample solution is substituted into the standard curve, the ratio of chiral inositol to inositol is calculated. When Be Y ≠Be b When, according to Formula I, the sample solution at a Baume degree of Be is calculated. b Optical rotation B at that time; Formula I; Substitute the optical rotation B into the standard curve to calculate the ratio of chiral inositol to inositol.

2. The method according to claim 1, characterized in that, The Baume degree of the standard solution is 5-10%.

3. The method according to claim 1 or 2, characterized in that, The chiral inositol content is 10-90% based on the total mass of chiral inositol and inositol in the standard solution.

4. The method according to claim 1 or 2, characterized in that, The Baume degree of the sample solution is 5-10%.

5. The method according to claim 1 or 2, characterized in that, When determining the optical rotation of each standard solution, the temperature of each standard solution is the same, denoted as Tb; Tb is 20℃ to 25℃.

6. The method according to claim 5, characterized in that, When determining the optical rotation of the sample solution, the temperature of the sample solution is Ti; Ti is 20°C to 40°C.

7. The method according to claim 6, characterized in that, When Be Y =Be b When Ti = Tb, the optical rotation A of the sample solution is substituted into the standard curve to calculate the ratio of chiral inositol to inositol.

8. The method according to claim 6, characterized in that, When Be Y =Be b And Ti≠Tb ‌ Then, calculate the optical rotation A of the sample solution at temperature Tb according to Formula II. Tb , A Tb =A Ti -[-0.00075×(Ti - Tb)] Formula II; Among them, A Tb It is the optical rotation value of the sample solution at temperature Tb, -0.00075 is the temperature coefficient, and A Ti It is the optical rotation value of the sample solution at a temperature of Ti; Optical rotation A Tb Substitute the values ​​into the standard curve to calculate the ratio of chiral inositol to inositol.

9. The method according to claim 8, characterized in that, When Be Y ≠Be b And Ti≠Tb ‌ Then, calculate the optical rotation A of the sample solution at temperature Tb according to Formula II. Tb Optical rotation A Tb Substituting into Formula I, the sample solution at a Baume degree of Be is calculated. b The optical rotation B at that time is used to calculate the ratio of chiral inositol to inositol by substituting the optical rotation B into the standard curve.

10. The method according to claim 1 or 2, characterized in that, The sample solution is a production feed solution for the enzymatic conversion of inositol into D-chiral inositol.

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