A method for extracting inositol from an inositol mother liquor

Abstract

The application discloses a method for extracting inositol from inositol mother liquor, which comprises the following steps: chromatographically separating inositol mother liquor through calcium type chromatographic separation resin, collecting inositol chromatographic extract to remove impurities such as glucose and inorganic salts in the inositol mother liquor; concentrating through a reverse osmosis membrane, evaporating and concentrating, and cooling to obtain crystal slurry; and adding low-molecular alcohol to the crystal slurry and stirring, so that alcohol-soluble impurities such as glycerol in the mother liquor are removed, and the recovery rate of inositol is improved; and through centrifugation and drying, inositol crude product is obtained.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of myo-inositol microbial production, and particularly relates to a myo-inositol extraction method in myo-inositol mother liquor. BACKGROUND

[0002] Myo-inositol is also known as cyclohexanehexol or phytol, which is a water-soluble vitamin belonging to the vitamin B family and has been used in the global market for more than half a century. Myo-inositol is mainly used in the industries of medicine, food and health products, and feed additives.

[0003] The traditional production method of myo-inositol is a pressurized hydrolysis method, which is the main process technology adopted by domestic manufacturers. The process flow is as follows: raw material acid leaching-neutralization, filtration, washing-creatinine crude product-decolorization, filtration-refined phytate-pressurized hydrolysis-neutralization of hydrolysis liquid, filtration-decolorization, filtration-concentration, crystallization-impurity removal by dissolution and crystallization-crystallization centrifugation-myoinositol fine product. This method has the disadvantages of strict requirements for equipment, high one-time equipment investment, low yield, complex subsequent refining process, serious pollution to water sources, and high production cost. Compared with the hydrolysis method, the microbial fermentation method is carried out under relatively mild conditions, and has the advantages of low microbial fermentation temperature and pressure, and no need for high-temperature and high-pressure equipment, which is the development direction of myo-inositol production in the future. The microbial fermentation technology is to produce myo-inositol by fermentation with glycerol and glucose as carbon sources. The obtained fermentation liquor is subjected to processes such as ultrafiltration, nanofiltration, decolorization, concentration, cooling crystallization, and drying to obtain qualified products. In the process, the mother liquor produced contains impurities such as glucose, glycerol, organic impurities, and inorganic salts in addition to myo-inositol. The repeated recycling of the mother liquor is prone to enrichment of impurities in the product, which affects the purity of the product. Therefore, how to efficiently recover myo-inositol from the mother liquor while preventing the enrichment of impurities is a problem to be solved. SUMMARY

[0004] Based on the technical problems existing in the background technology, the present application provides a myo-inositol extraction method in myo-inositol mother liquor, which removes alcohol-soluble impurities such as glucose and glycerol in the mother liquor by calcium-type chromatographic separation resin, membrane concentration crystallization, and alcohol precipitation, and improves the recovery rate of myo-inositol.

[0005] The myo-inositol extraction method in myo-inositol mother liquor provided by the present application comprises the following steps:

[0006] S1, subjecting the myo-inositol mother liquor to chromatographic separation by calcium-type chromatographic separation resin, and collecting myo-inositol chromatographic extract;

[0007] S2, concentrating the myo-inositol chromatographic extract by reverse osmosis membrane, and collecting reverse osmosis concentrate;

[0008] S3, evaporating and concentrating the reverse osmosis concentrate, and cooling to obtain crystal slurry;

[0009] S4, adding low-molecular alcohol to the crystal slurry, stirring, and centrifuging to obtain myo-inositol crude product.

[0010] Preferably, the myo-inositol mother liquor is obtained by separating myo-inositol from the myo-inositol fermentation liquor.

[0011] In the present application, myo-inositol can be separated from the myo-inositol fermentation liquor by ceramic membrane filtration, nanofiltration membrane filtration, activated carbon decolorization, evaporation concentration, cooling crystallization, etc.

[0012] Preferably, in S1, the calcium-type chromatography resin is LX-1850.

[0013] Preferably, in S1, the chromatography separation conditions are as follows: operating temperature 55-65℃, feed flow rate 3BV / h, water flow rate 3BV / h, feed volume 0.3-0.5BV, elution water volume 0.5-1.0BV, chromatography extract volume 0.5-0.9BV, and chromatography extract residue volume 0.4-0.7BV.

[0014] Preferably, in S2, the concentration conditions of the reverse osmosis membrane are as follows: operating temperature 30-45℃, operating pressure 25-65bar, and concentration to myo-inositol concentration 250-350g / L in the reverse osmosis concentrate.

[0015] Preferably, in S3, the reverse osmosis concentrate is further subjected to decolorization treatment and then evaporation concentration.

[0016] In the present application, the reverse osmosis membrane pre-concentration is used to improve the activated carbon decolorization effect and reduce the evaporation concentration cost.

[0017] Preferably, in S3, the evaporation concentration conditions are as follows: heating temperature 65-85℃, vacuum degree -0.07 to -0.1Mpa, and evaporation concentration to myo-inositol concentration 550-700g / L.

[0018] Preferably, in S3, the temperature is lowered to 25-35℃ at a cooling rate of 0.2-0.5℃ / min.

[0019] Preferably, in S4, the low-molecular alcohol is methanol or ethanol; preferably, the addition amount of the low-molecular alcohol is 0.2-0.5 times the volume of the crystal slurry; preferably, the low-molecular alcohol is added in the form of uniform flow addition, and the total uniform flow addition time is 2-6h.

[0020] Preferably, in S4, the stirring speed is 100-150rpm, and the stirring time is 1-3h.

[0021] Beneficial effects: The present application realizes effective separation of glucose and inorganic salts and other impurities in the myo-inositol mother liquor from myo-inositol by using calcium-type chromatography separation resin; and removes alcohol-soluble impurities such as glycerol in the mother liquor and improves the myo-inositol recovery rate by pre-concentration, evaporation cooling crystallization and alcohol precipitation, etc. DETAILED DESCRIPTION

[0022] The extraction total yield in the following examples = (total mass of crude inositol / mass of inositol in inositol mother liquor) x 100%;

[0023] The detection of inositol, glucose and glycerol in the crude inositol was performed by high performance liquid chromatography-differential detector.

[0024] Hereinafter, the technical solutions of the present application will be described in detail through specific examples.

[0025] Example 1

[0026] A method for extracting inositol from an inositol mother liquor, comprising the following steps:

[0027] (1) Preparation of inositol mother liquor: Take inositol fermentation liquor (containing 95 g / L of inositol) and sequentially filter through a 50 nm ceramic membrane, filter through a nanofiltration membrane with a molecular weight cut-off of 1000 daltons, decolorize with 0.5% (mass of activated carbon / volume of liquor) of activated carbon at 50°C for 30 min, then evaporate and concentrate at 75°C and -0.08 MPa to a inositol concentration of 550 g / L, cool to 25°C and filter to obtain inositol crystals and inositol mother liquor. Detection shows that the inositol concentration in the mother liquor is 156.2 g / L, the glucose concentration is 3.3 g / L, and the glycerol concentration is 1.7 g / L;

[0028] (2) Chromatographic separation: Take 15 L of the inositol mother liquor from step (1) and heat to 60°C, then separate and remove impurities by passing through a Blue-X LX-1850 calcium type chromatographic separation resin to obtain chromatographic extraction liquid and chromatographic extraction residual liquid; the resin separation conditions are as follows: operating temperature 60°C, feed flow rate 3.0 BV / h, water flow rate 3.0 BV / h, feed volume 0.3 BV, elution water volume 0.7 BV, chromatographic extraction liquid volume 0.6 BV, and chromatographic extraction residual liquid volume 0.4 BV;

[0029] (3) RO membrane pre-concentration: Concentrate the chromatographic extraction liquid in step (2) by passing through an RO membrane to obtain RO membrane concentrate; the RO membrane operating conditions are as follows: use an RO membrane with an effective molecular weight cut-off of 150 daltons, operate at a temperature of 35°C and a pressure of 45 bar, and concentrate to a inositol concentration of 280 g / L in the RO membrane concentrate;

[0030] (4) Decolorization: Take the RO membrane concentrate in step (3) and perform activated carbon decolorization; the activated carbon decolorization conditions are as follows: use powdered activated carbon, the activated carbon addition amount is 0.5% (w / v), the decolorization temperature is 50°C, and the decolorization time is 30 min;

[0031] (5) Concentration: Take the decolorized clear liquid in step (4) and evaporate and concentrate at 80°C and -0.08 MPa to a inositol concentration of 580 g / L, then cool to 25°C at a rate of 0.5°C / min under stirring to obtain a crystal slurry.

[0032] (6) Alcohol precipitation: Take 2.5 L of the crystal slurry in step (5), and add 750 mL of anhydrous methanol to the crystal slurry at a flow rate of 150 mL / h under stirring at a speed of 150 rpm. After the addition of the anhydrous methanol is completed, continue to maintain for 2 h to obtain an alcohol precipitation slurry;

[0033] (7) Solid-liquid separation: Take the alcohol precipitation slurry in step (6) and centrifuge at a centrifugal force of 1950 g to obtain a crude inositol product and a methanol filtrate. Dry the crude inositol product at 80°C until the weight is constant, and then detect the dry weight of the crude inositol product and the mass fraction of inositol.

[0034] Example 2

[0035] (1) Preparation of inositol mother liquor: The same as in Example 1;

[0036] (2) Chromatographic separation: Take 15 L of the inositol mother liquor in step (1) and heat to 60°C, and then separate and remove impurities by passing through a Blax LX-1850 calcium type chromatographic separation resin to obtain a chromatographic extract and a chromatographic extract residue; the resin separation conditions are as follows: operating temperature 60°C, feed flow rate 3.0 BV / h, water flow rate 3.0 BV / h, feed volume 0.3 BV, elution water volume 0.7 BV, chromatographic extract volume 0.5 BV, and chromatographic extract residue volume 0.5 BV;

[0037] (3) RO membrane pre-concentration: Take the chromatographic extract in step (2) and concentrate by passing through an RO membrane to obtain an RO membrane concentrate; the RO membrane operating conditions are as follows: an RO membrane with an effective molecular weight cut-off of 150 daltons is used, the operating temperature is 35°C, the operating pressure is 45 bar, and the concentration is performed to an inositol concentration of 280 g / L in the RO membrane concentrate;

[0038] (4) Decolorization: Take the RO membrane concentrate in step (3) and perform activated carbon decolorization; the activated carbon decolorization conditions are as follows: powdered activated carbon is used, the activated carbon addition amount is 0.5% (w / v), the decolorization temperature is 50°C, and the decolorization time is 30 min;

[0039] (5) Concentration: Take the decolorized clear liquid in step (4) and evaporate and concentrate at 80°C and -0.08 Mpa to an inositol concentration of 580 g / L, and then cool to 25°C at a rate of 0.5°C / min under stirring to obtain a crystal slurry;

[0040] (6) Alcohol precipitation: Take 2.5 L of the crystal slurry in step (5), and add 600 mL of anhydrous methanol to the crystal slurry at a flow rate of 150 mL / h under stirring at a speed of 150 rpm. After the addition of the anhydrous methanol is completed, continue to maintain for 2 h to obtain an alcohol precipitation slurry;

[0041] (7) Solid-liquid separation: The alcohol precipitation slurry in step (6) was subjected to centrifugation at a centrifugal force of 1950 g to obtain a crude inositol product and a methanol filtrate. The crude inositol product was dried at 80°C until the weight was constant, and then the dry weight of the crude inositol product and the mass fraction of inositol were detected.

[0042] Example 3

[0043] (1) Preparation of inositol mother liquor: same as Example 1;

[0044] (2) Chromatographic separation: 15 L of the inositol mother liquor in step (1) was heated to 60°C, and then subjected to separation and impurity removal by passing through a Blax LX-1850 calcium type chromatographic separation resin to obtain a chromatographic extract and a chromatographic extract residue; the resin separation conditions were as follows: operating temperature 60°C, feed flow rate 3.0 BV / h, water flow rate 3.0 BV / h, feed volume 0.3 BV, elution water volume 0.8 BV, chromatographic extract volume 0.6 BV, and chromatographic extract residue volume 0.5 BV;

[0045] (3) RO membrane pre-concentration: the chromatographic extract in step (2) was subjected to RO membrane concentration to obtain an RO membrane concentrate, and the RO membrane operating conditions were as follows: an RO membrane with an effective molecular weight cut-off of 150 daltons was used, the operating temperature was 35°C, the operating pressure was 45 bar, and the concentration was performed until the inositol concentration in the RO membrane concentrate was 280 g / L;

[0046] (4) Decolorization: the RO membrane concentrate in step (3) was subjected to activated carbon decolorization, and the activated carbon decolorization conditions were as follows: powdered activated carbon was used, the activated carbon addition amount was 0.5% (w / v), the decolorization temperature was 50°C, and the decolorization time was 30 min;

[0047] (5) Concentration: the decolorized clear liquid in step (4) was evaporated and concentrated at 80°C and -0.08 Mpa until the inositol concentration was 580 g / L, and then the temperature was reduced to 25°C at a rate of 0.5°C / min under stirring to obtain a crystal slurry;

[0048] (6) Alcohol precipitation: 2.5 L of the crystal slurry in step (5) was added with 600 mL of anhydrous methanol at a flow rate of 150 mL / h under stirring at a stirring speed of 150 rpm, and after the addition of anhydrous methanol was completed, the stirring was continued for 2 h to obtain an alcohol precipitation slurry;

[0049] (7) Solid-liquid separation: the alcohol precipitation slurry in step (6) was subjected to centrifugation at a centrifugal force of 1950 g to obtain a crude inositol product and a methanol filtrate. The crude inositol product was dried at 80°C until the weight was constant, and then the dry weight of the crude inositol product and the mass fraction of inositol were detected.

[0050] Example 4

[0051] (1) Preparation of inositol mother liquor: same as Example 1;

[0052] (2) Chromatographic separation: 15 L of the inositol mother liquor of step (1) was warmed to 60°C, and then passed through a Lanxiao LX-1850 calcium type chromatographic separation resin to separate and remove impurities, to obtain a chromatographic extract and a chromatographic extract residue; the resin separation conditions were: operating temperature 60°C, feed flow rate 3.0 BV / h, water flow rate 3.0 BV / h, feed volume 0.3 BV, elution water volume 0.8 BV, chromatographic extract volume 0.6 BV, and chromatographic extract residue volume 0.5 BV;

[0053] (3) RO membrane pre-concentration: the chromatographic extract of step (2) was subjected to RO membrane concentration, to obtain an RO membrane concentrate; the RO membrane operating conditions were: an RO membrane with an effective molecular weight cut-off of 150 daltons was used, the operating temperature was 35°C, the operating pressure was 45 bar, and the concentration was performed until the inositol concentration in the RO membrane concentrate was 280 g / L;

[0054] (4) Decolorization: the RO membrane concentrate of step (3) was subjected to activated carbon decolorization; the activated carbon decolorization conditions were: powdered activated carbon was used, the activated carbon addition amount was 0.5% (w / v), the decolorization temperature was 50°C, and the decolorization time was 30 min;

[0055] (5) Concentration: the decolorized clear liquid of step (4) was evaporated and concentrated at 80°C and -0.08 MPa until the inositol concentration was 630 g / L, and then the temperature was reduced to 25°C at a rate of 0.5°C / min under stirring, to obtain a crystal slurry;

[0056] (6) Alcohol precipitation: 2.5 L of the crystal slurry of step (5) was added with 600 mL of anhydrous methanol at a flow rate of 150 mL / h under stirring at a speed of 150 rpm, and the anhydrous methanol was continuously added for 2 h after the addition was completed, to obtain an alcohol precipitation slurry;

[0057] (7) Solid-liquid separation: the alcohol precipitation slurry of step (6) was subjected to centrifugation at a centrifugal force of 1950 g, to obtain inositol crude and methanol filtrate; the inositol crude was dried at 80°C until the weight was constant, and then the inositol crude dry weight and the inositol mass fraction were detected.

[0058] Example 5

[0059] (1) Preparation of inositol mother liquor: same as in Example 1;

[0060] (2) Chromatographic separation: 15 L of the inositol mother liquor of step (1) was warmed to 60°C, and then passed through a Lanxiao LX-1850 calcium type chromatographic separation resin to separate and remove impurities, to obtain a chromatographic extract and a chromatographic extract residue; the resin separation conditions were: operating temperature 60°C, feed flow rate 3.0 BV / h, water flow rate 3.0 BV / h, feed volume 0.3 BV, elution water volume 0.8 BV, chromatographic extract volume 0.6 BV, and chromatographic extract residue volume 0.5 BV;

[0061] (3) RO membrane pre-concentration: taking the chromatography extract in step (2) for RO membrane concentration to obtain RO membrane concentrate, the RO membrane operating conditions are: using RO membrane with effective molecular weight cutoff of 150 Dalton, operating temperature of 35°C, operating pressure of 45 bar, and concentrating to inositol concentration of 280 g / L in the RO membrane concentrate;

[0062] (4) decolorization: taking the RO membrane concentrate in step (3) for active carbon decolorization, the active carbon decolorization conditions are: using powdered active carbon, active carbon addition amount of 0.5% (w / v), decolorization temperature of 50°C, and decolorization time of 30 min;

[0063] (5) concentration: taking the decolorized clear liquid in step (4) to evaporate and concentrate at 80°C and -0.08 Mpa to inositol concentration of 630 g / L, then reducing the temperature to 25°C at 0.3°C / min under stirring to obtain crystal slurry;

[0064] (6) alcohol precipitation: taking 2.5 L of the crystal slurry in step (5) to add 600 mL of anhydrous methanol to the crystal slurry at a flow rate of 150 mL / h under stirring at 150 rpm, and continuing to maintain for 2 h after the addition of anhydrous methanol is completed to obtain alcohol precipitation slurry;

[0065] (7) solid-liquid separation: taking the alcohol precipitation slurry in step (6) to centrifuge at a centrifugal force of 1950 g to obtain inositol crude product and methanol filtrate, and detecting the inositol crude product dry weight mass and inositol mass proportion after drying the inositol crude product at 80°C to constant weight.

[0066] Example 6

[0067] (1) preparation of inositol mother liquor: same as example 1;

[0068] (2) chromatography separation: taking 15 L of the inositol mother liquor in step (1) to heat to 60°C, then separating and removing impurities by passing through a blue Xiao LX-1850 calcium type chromatography separation resin to obtain chromatography extract and chromatography extract residue; the resin separation conditions are: operating temperature of 60°C, feed flow rate of 3.0 BV / h, water flow rate of 3.0 BV / h, feed volume of 0.3 BV, elution water volume of 0.8 BV, chromatography extract volume of 0.6 BV, and chromatography extract residue volume of 0.5 BV;

[0069] (3) RO membrane pre-concentration: taking the chromatography extract in step (2) for RO membrane concentration to obtain RO membrane concentrate, the RO membrane operating conditions are: using RO membrane with effective molecular weight cutoff of 150 Dalton, operating temperature of 35°C, operating pressure of 45 bar, and concentrating to inositol concentration of 280 g / L in the RO membrane concentrate;

[0070] (4) decolorization: taking the RO membrane concentrated solution in step (3) for activated carbon decolorization, the activated carbon decolorization conditions are as follows: using powdered activated carbon, the activated carbon addition amount is 0.5% (w / v), the decolorization temperature is 50°C, and the decolorization time is 30 min;

[0071] (5) concentration: taking the decolorized clear solution in step (4) to evaporate and concentrate at 80°C and -0.08 Mpa to an inositol concentration of 630 g / L, then reducing the temperature to 25°C at a stirring condition of 0.2°C / min, to obtain a crystal slurry;

[0072] (6) alcohol precipitation: taking 2.5 L of the crystal slurry in step (5), adding 600 mL of anhydrous methanol to the crystal slurry at a flow rate of 150 mL / h under a stirring speed of 150 rpm, and continuing to maintain for 2 h after the addition of the anhydrous methanol is completed, to obtain an alcohol precipitation slurry;

[0073] (7) solid-liquid separation: taking the alcohol precipitation slurry in step (6) to centrifuge at a centrifugal force of 1950 g, to obtain an inositol crude product and a methanol filtrate, and detecting the dry weight of the inositol crude product and the inositol mass percentage after drying the inositol crude product at 80°C to a constant weight.

[0074] Comparative Example

[0075] (1) preparation of inositol mother liquor: same as Example 1;

[0076] (2) taking 15 L of the inositol mother liquor in step (1) to evaporate and concentrate at 80°C and -0.08 Mpa to an inositol concentration of 630 g / L, then reducing the temperature to 25°C at a stirring condition of 0.2°C / min, to obtain a crystal slurry;

[0077] (3) alcohol precipitation: taking 2.5 L of the crystal slurry in step (2), adding 600 mL of anhydrous methanol to the crystal slurry at a flow rate of 150 mL / h under a stirring speed of 150 rpm, and continuing to maintain for 2 h after the addition of the anhydrous methanol is completed, to obtain an alcohol precipitation slurry;

[0078] (4) solid-liquid separation: taking the alcohol precipitation slurry in step (3) to centrifuge at a centrifugal force of 1950 g, to obtain a first inositol crude product and a methanol filtrate;

[0079] (5) sedimentation separation: taking the methanol filtrate in step (4) to stand for 2 h, collecting the lower slurry to centrifuge at a centrifugal force of 1950 g, to obtain a second inositol crude product and a methanol filtrate;

[0080] (6) mixing and drying: mixing the first inositol crude product obtained in step (4) and the second inositol crude product obtained in step (5), and drying at 80°C to a constant weight, and detecting the dry weight and the inositol mass percentage.

[0081] Table 1: mass percentage of each component in the inositol crude product of Examples 1-6 and the comparative example

[0082]

[0083]

[0084] The above description is merely that of the preferred embodiments of the present application, but the protection scope of the present application is not limited thereto, and any person skilled in the art, according to the technical range disclosed by the present application and the inventive concept thereof, can make equivalent replacements or changes, which should be encompassed in the protection scope of the present application.

Claims

1. A method for extracting inositol from an inositol mother liquor, characterized by, It comprises the following steps: S1, chromatographically separating the inositol mother liquor through a calcium type chromatographic separation resin, and collecting inositol chromatographic extract; Wherein, the inositol mother liquor is obtained by separating and extracting inositol from inositol fermentation liquor, and the fermentation liquor after extracting inositol is the inositol mother liquor; The chromatographic separation conditions are: running temperature 55-65℃, feed flow rate 3BV / h, water flow rate 3BV / h, feed volume 0.3-0.5BV, elution water volume 0.5-1.0BV, chromatographic extract volume 0.5-0.9BV, and chromatographic extract residue volume 0.4-0.7BV; S2, concentrating the inositol chromatographic extract through a reverse osmosis membrane, and collecting reverse osmosis concentrate; S3, evaporating and concentrating the reverse osmosis concentrate, cooling, and obtaining crystal slurry; S4, adding low molecular alcohol to the crystal slurry, stirring, and centrifuging to obtain inositol crude product.

2. The method of claim 1, wherein, In S1, the calcium type chromatographic resin is LX-1850.

3. The method of claim 1, wherein, In S2, the concentration conditions of the reverse osmosis membrane are: running temperature 30-45℃, running pressure 25-65bar, and concentrating to inositol concentration 250-350g / L in the reverse osmosis concentrate.

4. The method of claim 1, wherein, In S3, the reverse osmosis concentrate is first subjected to decolorization treatment, and then evaporated and concentrated.

5. The method of claim 1, wherein, In S3, the evaporation and concentration conditions are: heating temperature 65-85℃, vacuum degree -0.07 to -0.1Mpa, and evaporating and concentrating to inositol concentration 550-700g / L.

6. The method of claim 1, wherein, In S3, the cooling rate is 0.2-0.5℃ / min to 25-35℃.

7. The method of claim 1, wherein, In S4, the low molecular alcohol is methanol or ethanol.

8. The method of claim 7, wherein, The addition amount of the low molecular alcohol is 0.2-0.5 times the volume of the crystal slurry.

9. The method of claim 7, wherein, The low molecular alcohol is added in a uniform flow rate, and the total uniform flow rate addition time is 2-6h.

10. The method of claim 1, wherein, In S4, the stirring speed is 100-150rpm, and the stirring time is 1-3h.

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