A process for simultaneously preparing baicalein, baicalin and flavones of scutellaria

Abstract

The application discloses a process method for simultaneously preparing baicalein, baicalin and baicalin flavones, relates to the technical field of plant extraction, and is characterized in that after baicalin root is crushed and extracted, the extract is concentrated and extracted under different pH values, and after the two extraction phases and the raffinate phases are respectively desolventized, acid precipitated and concentrated, baicalein, baicalin and baicalin flavones are obtained, the utilization rate of raw materials is greatly improved, waste is reduced, the content of baicalin polysaccharide products obtained after the secondary raffinate phases are adsorbed, resolved and concentrated is between 35 wt% and 50 wt%, economic benefits are further improved, waste discharge is small, the environment is friendly, the process and equipment are simple, the cost of raw materials is low, economic benefits are high, and the method is suitable for industrialized production.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of plant extraction, and particularly relates to a process for simultaneously preparing baicalein, baicalin and scutellarein. BACKGROUND

[0002] Scutellaria baicalensis Georgi is a plant of the Scutellaria genus in the Labiatae family. It tastes bitter and is cold in nature, and is attributed to the lung, gallbladder, spleen, large intestine and small intestine channels. It has the effects of clearing heat and drying dampness, purging fire and detoxifying, stopping bleeding and preventing miscarriage. It has a long history of use and is used to treat damp-warm, summer dampness, lung heat and phlegm, cough with thick sputum, blood-heat causing hematemesis, epistaxis, carbuncle and sore with toxic, and blood-heat causing miscarriage. The main chemical components of Scutellaria baicalensis Georgi include flavonoids, polysaccharides, alkaloids, phenylpropanoids, volatile oils and the like. Among them, flavonoids are important components in Scutellaria baicalensis Georgi, and have various biological activities such as anti-inflammatory, antioxidant, antibacterial and antitumor activities.

[0003] Although Scutellaria baicalensis Georgi has various components with medicinal value, most pharmaceutical factories currently only use Scutellaria baicalensis Georgi medicinal materials to produce baicalin, and a large amount of effective components with medicinal value are directly discarded, which not only pollutes the environment, but also causes great waste of resources and loss of economic benefits.

[0004] A method for simultaneously extracting baicalin, baicalein and wogonin from Scutellaria baicalensis Georgi is introduced in Chinese Patent No. CN104610401B. The patent uses water extraction and concentration on Scutellaria baicalensis Georgi, macroporous adsorption resin adsorption, water washing and gradient ethanol elution to collect the eluate respectively; the eluate containing baicalin is concentrated under reduced pressure, the pH is adjusted, and then it is incubated, left standing, filtered to obtain baicalin product; the eluate containing baicalein and wogonin is evaporated to dryness, and then the gel column is used twice to elute with methanol, and the baicalein fraction and the wogonin fraction are collected separately, and then the methanol is removed to obtain baicalein and wogonin products respectively. The patent needs two times of concentration, which increases the energy consumption of the product, and the product solvent consumption is increased due to two times of column adsorption and small treatment capacity of single batch of resin, thereby increasing the production cost of the product.

[0005] Chinese Patent No. CN107362198A introduces a Scutellaria baicalensis Georgi flavone extraction process, Scutellaria baicalensis Georgi flavone extract and its application. The patent uses Scutellaria baicalensis Georgi roots as raw materials, and Scutellaria baicalensis Georgi is extracted by ultrasonic extraction, and then the extract is separated, concentrated and purified by a macroporous resin column to obtain Scutellaria baicalensis Georgi flavone extract. The cost used in the patent is high, and it is not suitable for industrial production.

[0006] Chinese Patent No. CN107648310A introduces a high-purity Scutellaria baicalensis Georgi total flavone and a preparation method thereof. The patent uses Scutellaria baicalensis Georgi roots as raw materials, and the product is obtained by ethanol reflux extraction, concentration and de-alcoholization, column adsorption, ethanol resolution, concentration and drying. The method is relatively complicated, and the extraction rate of Scutellaria baicalensis Georgi is not high, which is easy to cause the loss of effective components. SUMMARY

[0007] The technical problem solved by the present application is to provide a process method for simultaneously preparing baicalein, baicalin and baicalin flavones, which has low production cost, high economic benefit and is suitable for industrial production.

[0008] To solve the above technical problem, the technical scheme of the present application is:

[0009] A process method for simultaneously preparing baicalein, baicalin and baicalin flavones, comprising the following steps:

[0010] S1: crushing and extraction

[0011] Take the roots of Scutellaria baicalensis Georgi, crush and extract 2-3 times with 7-12 BV boiling water, each time for 0.5-2 h, to obtain an extract;

[0012] S2: concentration

[0013] Concentrate the extract in S1 at a temperature of 60-90 ℃ and a pressure of -0.04 to -0.1 MPa to a solid content of 20-35 wt%, to obtain a concentrated solution;

[0014] S3: first extraction

[0015] After adjusting the pH of the concentrated solution in S2 to 4.0-5.0, pump it into an extraction tank and extract it 2-3 times with water-saturated ethyl acetate to obtain a first raffinate and a first extract;

[0016] S4: second extraction

[0017] After adjusting the pH of the first raffinate in S3 to 2.5-3.5, pump it into an extraction tank and extract it 2-3 times with water-saturated ethyl acetate to obtain a second raffinate and a second extract;

[0018] S5: desolventizing I

[0019] Concentrate and desolventize the first extract in S3 at a temperature of 60-90 ℃ and a pressure of -0.04 to -0.1 MPa, and dilute it with water to a solid content of 2 wt% to 5 wt% to obtain a solution I;

[0020] S6: acid precipitation I

[0021] Heat the solution I in S5 to 70 ℃-95 ℃, adjust the pH to 2-2.5, stir for 10-20 min, and crystallize for 1-5 h, then filter and rinse to obtain a filtrate I and a filter cake I, which is dried and crushed to obtain a baicalein product, wherein the baicalein content is ≥98 wt%;

[0022] S7: desolventizing II

[0023] The secondary extraction phase in S4 is heated and concentrated to remove solvent at a temperature of 60-90℃ and a pressure of -0.04 to -0.1 MPa, and then diluted with water to a solid content of 2wt% to 10wt%, to obtain solution two;

[0024] S8: acid precipitation of two

[0025] The solution two in S7 is warmed to 90-100℃, the pH is adjusted to 1.5-2.0, stirred for 10-20 min, and incubated for 0.5-3 h, and the supernatant is separated, and the precipitate is filtered and washed, to obtain filtrate two and filter cake two, which is dried and crushed to obtain the product baicalin, wherein the baicalin content is ≥90wt%, and the filtrate two is combined with the supernatant;

[0026] S9: nanofiltration membrane filtration

[0027] The filtrate one in S6 and the supernatant in S8 are combined, the pH is adjusted to 4-5.5, the temperature is controlled at 25-50℃, and the pressure is 1.0-2.5 MPa, and then nanofiltration membrane filtration is performed, to obtain nanofiltration concentrated solution and nanofiltration permeate;

[0028] S10: concentration and drying

[0029] The nanofiltration concentrated solution in S9 is heated and concentrated, and then dried, to obtain the product of flavonoids of Scutellaria baicalensis Georgi, wherein the content of flavonoids of Scutellaria baicalensis Georgi is 25-45wt%.

[0030] Preferably, the volume ratio of the raffinate phase to water saturated ethyl acetate in each extraction in steps S3 and S4 is 1:1-3.

[0031] Preferably, the secondary raffinate phase in step S4 is adsorbed on a macroporous adsorption resin, 1-3 BV of purified water is used for elution, and then 2-4 BV of 70-85v / v% ethanol or methanol is used for elution, the eluate is concentrated and dried to obtain the product of polysaccharides of Scutellaria baicalensis Georgi, wherein the polysaccharide content is 35-50wt%, and the loading amount of the macroporous adsorption resin is 100ml of resin adsorbing 15-25g of the raffinate phase in terms of dry solid content, and the macroporous adsorption resin is one of DM30, LX-T81 or LX-T28.

[0032] Preferably, the eluate is heated and concentrated to remove solvent at a temperature of 60-90℃ and a pressure of -0.04 to -0.1 MPa, and then concentrated to a solid content of 25-55wt%, and then spray dried at an inlet temperature of 165-190℃ and an outlet temperature of 70-95℃, to obtain the product of polysaccharides of Scutellaria baicalensis Georgi.

[0033] Preferably, the concentrated solution in step S3, the primary raffinate phase in step S4, the solution one in step S6 and the solution two in step S8 are adjusted to pH with 1-40wt% hydrochloric acid solution, 1-40wt% phosphoric acid solution or 1-40wt% sulfuric acid solution.

[0034] Preferably, the nanofiltration membrane in step S9 has a molecular weight cut-off of 400-1000 Da.

[0035] Preferably, step S9 uses a 5-40 wt% NaOH solution, a 5-40 wt% KOH solution or 10-60 wt% ammonia water to adjust the pH.

[0036] Preferably, the nanofiltration permeate in step S9 is used as the water for extraction in S1.

[0037] Preferably, the nanofiltration concentrate in step S10 is heated and concentrated at a temperature of 60-90℃ and a pressure of -0.04 to -0.1 MPa, and concentrated to a solid content of 25-55 wt%, and then spray dried at an inlet temperature of 165-190℃ and an outlet temperature of 70-95℃ to obtain the scutellarein.

[0038] Due to the adoption of the above technical solutions, the present application has the following advantages:

[0039] 1. On the basis of obtaining baicalin with a content of ≥90 wt%, scutellarein with a content of ≥98 wt% and scutellarein with a content of 25-45 wt% can also be obtained, which has high added value and increases economic benefits.

[0040] 2. The secondary raffinate phase can be adsorbed, desorbed and concentrated to obtain scutellarein polysaccharide products with a content of 35-50 wt%, further improving economic benefits.

[0041] 3. The nanofiltration permeate can be used as the water for extraction of scutellaria root, avoiding waste and pollution to the environment.

[0042] 4. The process and equipment are simple, the raw material cost is low, the economic benefits are high, and it is suitable for industrial production. BRIEF DESCRIPTION OF DRAWINGS

[0043] Figure 1 is a chromatogram of the scutellarein product in Example 3 of the present application;

[0044] Figure 2 is a chromatogram of the baicalin product in Example 3 of the present application;

[0045] Figure 3 is a chromatogram of the scutellarein product in Example 3 of the present application. DETAILED DESCRIPTION

[0046] The present application will be further described below in conjunction with examples.

[0047] Example 1

[0048] A process for simultaneously preparing scutellarein, baicalin and scutellarein, characterized by comprising the following steps:

[0049] S1: crushing, extraction

[0050] Take 10 kg of Huangqi root, crush, and extract twice with 7 BV of boiling water, each time for 0.5 h, to obtain 135 L of extract;

[0051] S2: concentration

[0052] Concentrate the extract in S1 at a temperature of 60°C and a pressure of -0.1 MPa to a solid content of 20 wt%, to obtain 21.5 L of concentrated solution;

[0053] S3: first extraction

[0054] After adjusting the pH of the concentrated solution in S2 to 5.0 with 1 wt% hydrochloric acid solution, pump it into an extraction tank, extract twice with water-saturated ethyl acetate, combine the extraction phases, to obtain 22.0 L of first raffinate and 42.5 L of first extract, wherein the volume ratio of concentrated solution to water-saturated ethyl acetate is 1:1 for each extraction;

[0055] S4: second extraction

[0056] After adjusting the pH of the first raffinate in S3 to 3.5 with 10 wt% hydrochloric acid solution, pump it into an extraction tank, extract twice with water-saturated ethyl acetate, combine the extraction phases, to obtain 22.1 L of second raffinate and 43.9 L of second extract, wherein the volume ratio of first raffinate to water-saturated ethyl acetate is 1:1 for each extraction;

[0057] S5: desolventization I

[0058] Concentrate the first extract in S3 at a temperature of 60°C and a pressure of -0.1 MPa to remove the solvent, and dilute with water to a solid content of 2 wt%, to obtain 5.1 L of solution I;

[0059] S6: acid precipitation I

[0060] Heat solution I in S5 to 70°C, adjust the pH to 2.5 with 15 wt% hydrochloric acid solution, stir for 10 min, and incubate for 1 h to crystallize, filter and rinse, to obtain 5.3 L of filtrate I and filter cake I, which is dried and crushed to obtain 45.2 g of baicalein product, wherein the baicalein content is 98.6 wt%;

[0061] S7: desolventization II

[0062] Concentrate the second extract in S4 at a temperature of 60°C and a pressure of -0.1 MPa to remove the solvent, and dilute with water to a solid content of 2 wt%, to obtain 86.6 L of solution II;

[0063] S8: acid precipitation II

[0064] The solution in S7 is warmed to 90℃, pH is adjusted to 2.0 with 10wt% hydrochloric acid solution, stirred for 12 min, and incubated for 0.5 h. The supernatant 68.8 L is separated, and the precipitate is filtered, rinsed, dried, and crushed to obtain the product baicalin 995.6 g, wherein the baicalin content is 90.7wt%, and the supernatant is combined with the supernatant in S8;

[0065] S9: nanofiltration membrane filtration

[0066] The supernatant in S6 and the supernatant in S8 are combined, and pH is adjusted to 5.5 with 5wt% NaOH solution. The nanofiltration membrane filtration is performed at a temperature of 25℃ and a pressure of 1.0 MPa to obtain nanofiltration concentrated solution 4.0 L and nanofiltration permeate 89.8 L. The nanofiltration permeate is reused in the extraction water in S1, wherein the nanofiltration membrane has a molecular weight cut-off of 400 Da;

[0067] S10: concentration and drying

[0068] The nanofiltration concentrated solution in S9 is heated and concentrated at 60℃ and a pressure of -0.1 MPa until the solid content is 25wt%. Then, spray drying is performed at an inlet temperature of 165℃ and an outlet temperature of 70℃ to obtain baicalin flavones 375.4 g, wherein the baicalin flavone content is 29.9wt%.

[0069] S11: preparation of a baicalin polysaccharide product

[0070] The secondary raffinate phase in step S4 is adsorbed on a macroporous adsorption resin, and 1BV of purified water is used to top the material. Then, 2BV of 70v / v% ethanol is used to elute the solution. The eluate is heated and concentrated at a temperature of 60℃ and a pressure of -0.1 MPa until the solid content is 25wt%. Then, spray drying is performed at an inlet temperature of 165℃ and an outlet temperature of 70℃ to obtain the baicalin polysaccharide product 991.2 g, wherein the baicalin polysaccharide content is 40.8wt%. The loading amount of the macroporous adsorption resin is 100 ml of resin adsorbing 15 g of raffinate phase dry solid content. The macroporous adsorption resin is DM30.

[0071] Example 2

[0072] A process for simultaneously preparing baicalein, baicalin, and baicalin flavones, characterized by comprising the following steps:

[0073] S1: crushing and extraction

[0074] 10 kg of scutellaria root is crushed, and 9BV of boiling water is used to extract 3 times, each for 1 h, to obtain 262 L of extract;

[0075] S2: concentration

[0076] The extract solution in S1 was concentrated at a temperature of 70°C and a pressure of -0.08 MPa to a solid content of 25 wt% to obtain a concentrated solution 18.0 L;

[0077] S3: primary extraction

[0078] The concentrated solution in S2 was pumped into an extraction tank after being adjusted to pH 4.5 with a 20 wt% phosphoric acid solution, and was extracted twice with water-saturated ethyl acetate, and the extraction phases were combined to obtain a primary raffinate phase 18.1 L and a primary extract phase 53.8 L, wherein the volume ratio of the concentrated solution to water-saturated ethyl acetate was 1:1.5 for each extraction;

[0079] S4: secondary extraction

[0080] The primary raffinate phase in S3 was pumped into an extraction tank after being adjusted to pH 3.2 with a 20 wt% phosphoric acid solution, and was extracted twice with water-saturated ethyl acetate, and the extraction phases were combined to obtain a secondary raffinate phase 18.3 L and a secondary extract phase 54.1 L, wherein the volume ratio of the primary raffinate phase to water-saturated ethyl acetate was 1:1.5 for each extraction;

[0081] S5: desolventization I

[0082] The primary extract phase in S3 was concentrated at a temperature of 70°C and a pressure of -0.08 MPa to remove the solvent, and was diluted with water to a solid content of 3 wt% to obtain a solution I 3.8 L;

[0083] S6: acid precipitation I

[0084] The solution I in S5 was heated to 75°C, and was adjusted to pH 2 with a 30 wt% phosphoric acid solution, and was stirred for 15 min, and was crystallized for 2 h, and was filtered and rinsed to obtain a filtrate I 3.9 L and a filter cake I, and the filter cake I was dried and crushed to obtain a baicalein product 46.6 g, wherein the baicalein content was 98.4 wt%;

[0085] S7: desolventization II

[0086] The secondary extract phase in S4 was concentrated at a temperature of 70°C and a pressure of -0.08 MPa to remove the solvent, and was diluted with water to a solid content of 5 wt% to obtain a solution II 36.6 L;

[0087] S8: acid precipitation II

[0088] The solution II in S7 was heated to 95°C, and was adjusted to pH 1.5 with a 25 wt% phosphoric acid solution, and was stirred for 15 min, and was settled for 1 h, and the supernatant 28.2 L was separated, and the precipitate was filtered and rinsed to obtain a filtrate II 8.4 L and a filter cake II, and the filter cake II was dried and crushed to obtain a baicalin product 1012.1 g, wherein the baicalin content was 90.4 wt%, and the filtrate II was combined with the supernatant;

[0089] S9: nanofiltration

[0090] The filtrate 1 in S6 and the supernatant in S8 were combined, and pH was adjusted to 4 with 15wt% KOH solution, and nanofiltration was performed at a temperature of 35°C and a pressure of 2.0 MPa, to obtain a nanofiltration concentrate of 4.3 L and a nanofiltration permeate of 36.4 L, and the nanofiltration permeate was reused in S1 as the water for extraction, wherein the molecular weight cut-off of the nanofiltration membrane was 800 Da;

[0091] S10: concentration and drying

[0092] The nanofiltration concentrate in S9 was concentrated at a temperature of 70°C and a pressure of -0.08 MPa, to a solid content of 35wt%, and then spray-dried at an inlet temperature of 180°C and an outlet temperature of 80°C, to obtain the scutellaria flavones 371.7 g, wherein the content of scutellaria flavones was 30.3wt%.

[0093] S11: preparation of scutellaria polysaccharide product

[0094] The secondary extraction residue in S4 was adsorbed on a macroporous adsorption resin, and then eluted with 3BV of 75v / v% methanol, and the eluate was concentrated at a temperature of 70°C and a pressure of -0.08 MPa, to a solid content of 35wt%, and then spray-dried at an inlet temperature of 170°C and an outlet temperature of 80°C, to obtain the scutellaria polysaccharide product 1032.2 g, wherein the content of scutellaria polysaccharide was 38.9wt%, and wherein the loading amount of the macroporous adsorption resin was 100 ml of resin adsorbing 20 g of the residue phase folded by solid content, and the macroporous adsorption resin was LX-T81.

[0095] Example 3

[0096] A process for simultaneously preparing baicalein, scutellarin and scutellaria flavones, characterized in that it comprises the following steps:

[0097] S1: crushing and extraction

[0098] Take 10 kg of scutellaria root, crush and extract with 10BV boiling water for 3 times, each time for 1.5h, to obtain 289L of extraction liquid;

[0099] S2: concentration

[0100] The extraction liquid in S1 was concentrated at a temperature of 80°C and a pressure of -0.06 MPa, to a solid content of 30wt%, to obtain 16.0L of concentrated liquid;

[0101] S3: primary extraction

[0102] The concentrated solution in S2 was pumped into an extraction tank after adjusting pH to 4.3 with a 10wt% sulfuric acid solution, extracted twice with water-saturated ethyl acetate, and the extraction phases were combined to obtain a primary raffinate phase of 16.4L and a primary extract phase of 63.4L, wherein the volume ratio of the concentrated solution to water-saturated ethyl acetate was 1:2 for each extraction;

[0103] S4: Secondary extraction

[0104] The primary raffinate phase in S3 was pumped into an extraction tank after adjusting pH to 2.8 with a 25wt% phosphoric acid solution, extracted three times with water-saturated ethyl acetate, and the extraction phases were combined to obtain a secondary raffinate phase of 16.5L and a secondary extract phase of 98.4L, wherein the volume ratio of the primary raffinate phase to water-saturated ethyl acetate was 1:2 for each extraction;

[0105] S5: Desolventization I

[0106] The primary extract phase in S3 was heated and concentrated under desolventization at a temperature of 80℃ and a pressure of -0.06MPa, diluted with water to a solid content of 4wt%, and a solution I of 3.1L was obtained;

[0107] S6: Acid precipitation I

[0108] The solution I in S5 was heated to 85℃, adjusted to pH 2.3 with a 40wt% phosphoric acid solution, stirred for 20min, and crystallized for 4h, and then filtered and rinsed to obtain a filtrate I of 3.4L and a filter cake I, which was dried and crushed to obtain a baicalein product of 47.1g, wherein the baicalein content was 98.5wt%;

[0109] S7: Desolventization II

[0110] The secondary extract phase in S4 was heated and concentrated under desolventization at a temperature of 80℃ and a pressure of -0.06MPa, diluted with water to a solid content of 8wt%, and a solution II of 24.1L was obtained;

[0111] S8: Acid precipitation II

[0112] The solution II in S7 was heated to 95℃, adjusted to pH 1.8 with a 30wt% sulfuric acid solution, stirred for 20min, and settled for 2.5h, and then the supernatant of 19.6L was separated, and the precipitate was filtered and rinsed to obtain a filtrate II of 6.2L and a filter cake II, which was dried and crushed to obtain a baicalin product of 1021.4g, wherein the baicalin content was 90.6wt%, and the filtrate II was combined with the supernatant;

[0113] S9: Nanofiltration membrane filtration

[0114] The filtrate 1 in S6 and the supernatant in S8 are combined, pH is adjusted to 5.5 with 50wt% ammonia water, temperature is controlled at 40℃, pressure is controlled at 2.0MPa, and the mixture is filtered through a nanofiltration membrane to obtain a nanofiltration concentrate 4.8L and a nanofiltration permeate 25.4L, and the nanofiltration permeate is used in the water for extraction in S1, wherein the molecular weight cut-off of the nanofiltration membrane is 800Da;

[0115] S10: Concentration and drying

[0116] The nanofiltration concentrate in S9 is heated and concentrated at 80℃ and a pressure of -0.06MPa until the solid content is 45wt%, and then spray-dried at an inlet air temperature of 180℃ and an outlet air temperature of 80℃ to obtain 342.1g of scutellaria flavones, wherein the content of scutellaria flavones is 35.6wt%.

[0117] S11: Preparation of a scutellaria polysaccharide product

[0118] The secondary extraction residue in S4 is adsorbed on a macroporous adsorption resin, eluted with 3BV of purified water, and then eluted with 4BV of 80v / v% ethanol, and the eluate is heated and concentrated at 80℃ and a pressure of -0.06MPa until the solid content is 50wt%, and then spray-dried at an inlet air temperature of 180℃ and an outlet air temperature of 85℃ to obtain 964.3g of the scutellaria polysaccharide product, wherein the content of scutellaria polysaccharide is 41.7wt%, and wherein the amount of macroporous adsorption resin is 100ml of resin adsorbing 25g of the solid content of the extraction residue, and the macroporous adsorption resin is LX-T28.

[0119] Example 4

[0120] A process for simultaneously preparing baicalein, scutellarin and scutellaria flavones, characterized in that it comprises the following steps:

[0121] S1: Grinding and extraction

[0122] 10kg of scutellaria roots are ground and extracted twice with 12BV of boiling water, each time for 2h, to obtain 232L of extraction liquid;

[0123] S2: Concentration

[0124] The extraction liquid in S1 is heated and concentrated at 90℃ and a pressure of -0.04MPa until the solid content is 35wt% to obtain 12.6L of concentrated liquid;

[0125] S3: Primary extraction

[0126] The concentrated solution in S2 was pumped into an extraction tank after adjusting pH to 4.0 with 40wt% hydrochloric acid solution, extracted with water-saturated ethyl acetate for 3 times, and the extraction phases were combined to obtain 12.8L of primary raffinate and 112.9L of primary extract, wherein the volume ratio of the concentrated solution to water-saturated ethyl acetate was 1:3 in each extraction;

[0127] S4: Secondary extraction

[0128] The primary raffinate in S3 was pumped into an extraction tank after adjusting pH to 2.5 with 20wt% phosphoric acid solution, extracted with water-saturated ethyl acetate for 3 times, and the extraction phases were combined to obtain 13.0L of secondary raffinate and 115.0L of secondary extract, wherein the volume ratio of the primary raffinate to water-saturated ethyl acetate was 1:3 in each extraction;

[0129] S5: Desolventization I

[0130] The primary extract in S3 was heated and concentrated for desolventization at a temperature of 90℃ and a pressure of -0.04MPa, and then diluted with water to a solid content of 5wt% to obtain solution I of 2.6L;

[0131] S6: Acid precipitation I

[0132] Solution I in S5 was heated to 95℃, adjusted to pH 2.5 with 20wt% phosphoric acid solution, stirred for 20min, and then crystallized for 5h, and then filtered and rinsed to obtain filtrate I of 2.8L and filter cake I, which was dried and crushed to obtain baicalein product of 44.2g, wherein the baicalein content was 98.8wt%;

[0133] S7: Desolventization II

[0134] The secondary extract in S4 was heated and concentrated for desolventization at a temperature of 90℃ and a pressure of -0.04MPa, and then diluted with water to a solid content of 10wt% to obtain solution II of 19.6L;

[0135] S8: Acid precipitation II

[0136] Solution II in S7 was heated to 100℃, adjusted to pH 2.0 with 10wt% sulfuric acid solution, stirred for 20min, and then settled for 3h, and then the supernatant of 15.7L was separated, and the precipitate was filtered and rinsed to obtain filtrate II of 5.2L and filter cake II, which was dried and crushed to obtain baicalin product of 989.6g, wherein the baicalin content was 90.8wt%, and the filtrate II was combined into the supernatant;

[0137] S9: Nanofiltration membrane filtration

[0138] The filtrate 1 in S6 and the supernatant in S8 were combined, pH was adjusted to 5.5 with 40wt% ammonia water, temperature was controlled at 50°C, pressure was 2.5MPa, and the mixture was filtered through a nanofiltration membrane to obtain a nanofiltration concentrate 5.1L and a nanofiltration permeate 19.9L, and the nanofiltration permeate was reused in the water used for extraction in S1, wherein the molecular weight cut-off of the nanofiltration membrane was 1000Da;

[0139] S10: Concentration and drying

[0140] The nanofiltration concentrate in S9 was concentrated at 90°C and a pressure of -0.04MPa, and the concentration was stopped when the solid content reached 55wt%. The concentrated solution was then spray dried at an inlet temperature of 190°C and an outlet temperature of 95°C to obtain 394.5g of the scutellaria flavones, wherein the content of scutellaria flavones was 27.8wt%.

[0141] S11: Preparation of the scutellaria polysaccharide product

[0142] The secondary extraction raffinate in S4 was adsorbed on a macroporous adsorption resin, and then eluted with 4BV of 85v / v% methanol. The eluate was concentrated at 90°C and a pressure of -0.04MPa until the solid content reached 55wt%. The concentrated solution was then spray dried at an inlet temperature of 190°C and an outlet temperature of 95°C to obtain 805.2g of the scutellaria polysaccharide product, wherein the content of scutellaria polysaccharide was 47.2wt%. The loading amount of the macroporous adsorption resin was 100ml of resin adsorbing 23g of the raffinate in terms of dry solid content, and the macroporous adsorption resin was LX-T81.

[0143] It should be understood that the embodiments are only used for illustrating the present application but not for limiting the scope of the present application. Furthermore, it should be understood that those skilled in the art can make various modifications or changes to the present application after reading the content of the present application, and these equivalent forms also fall within the scope defined by the appended claims of the present application.

Claims

1. A process for simultaneously preparing baicalin, baicalin glycosides, and baicalein flavonoids, characterized in that... Includes the following steps: S1: Crushing, Extraction Take Scutellaria baicalensis root, crush it, and extract it with boiling water at 7-12 BV 2-3 times, each time for 0.5-2 hours, to obtain the extract; S2: Concentrated The extract of S1 was thermally concentrated at a temperature of 60-90℃ and a pressure of -0.04 to -0.1 MPa until the solid content was 20-35 wt% to obtain a concentrated solution. S3: Single Extraction After adjusting the pH of the concentrate in S2 to 4.0-5.0, pump it into the extraction tank and extract it 2-3 times with water-saturated ethyl acetate to obtain a primary raffinate phase and a primary extract phase. S4: Secondary Extraction After adjusting the pH of the primary raffinate in S3 to 2.5-3.5, pump it into the extraction tank and extract it 2-3 times with water-saturated ethyl acetate to obtain the secondary raffinate and secondary extract phase. S5: Desolventizing The primary extract phase in S3 was thermally concentrated and desolventized at a temperature of 60-90℃ and a pressure of -0.04 to -0.1 MPa, and then diluted with water to a solid content of 2wt% to 5wt% to obtain solution one. S6: Acid precipitation one Heat solution 1 in S5 to 70℃-95℃, adjust pH to 2-2.5, stir for 10-20 min, keep warm for crystallization for 1-5 h, filter and rinse to obtain filtrate 1 and filter cake 1. Dry and crush filter cake 1 to obtain baicalin product, wherein the baicalin content is ≥98wt%. S7: Desolventizing II The secondary extract phase in S4 was thermally concentrated and desolventized at a temperature of 60-90℃ and a pressure of -0.04 to -0.1MPa, and then diluted with water to a solid content of 2wt% to 10wt% to obtain solution two. S8: Acid precipitation II Heat solution 2 in S7 to 90-100℃, adjust pH to 1.5-2.0, stir for 10-20 min, keep warm and let it settle for 0.5-3 h, separate the supernatant, filter and wash the precipitate to obtain filtrate 2 and filter cake 2, dry and crush filter cake 2 to obtain baicalin product, wherein the baicalin content is ≥90wt%, and combine filtrate 2 with the supernatant; S9: Nanofiltration membrane filtration Combine the filtrate from S6 and the supernatant from S8, adjust the pH to 4-5.5, control the temperature at 25-50℃ and the pressure at 1.0-2.5MPa, and filter through a nanofiltration membrane to obtain nanofiltration concentrate and nanofiltration permeate. S10: Concentration and Drying The nanofiltration concentrate in S9 was concentrated by heat and dried to obtain scutellaria baicalensis flavonoids, with a content of 25-45 wt%.

2. The process for simultaneously preparing baicalein, baicalin, and baicalein flavonoids as described in claim 1, characterized in that: In steps S3 and S4, the volume ratio of the raffinate to water-saturated ethyl acetate in each extraction is 1:1-3.

3. The process for simultaneously preparing baicalin, baicalin glycosides, and baicalein flavonoids as described in claim 1, characterized in that: The secondary raffinate from step S4 is adsorbed onto a macroporous adsorption resin, topped with 1-3 BV of purified water, and then eluted with 2-4 BV of 70-85 v / v% ethanol or methanol. The eluent is concentrated and dried to obtain the Scutellaria baicalensis polysaccharide product, wherein the Scutellaria baicalensis polysaccharide content is 35-50 wt%. The sample loading amount of the macroporous adsorption resin is 100 ml of resin adsorbing 15-25 g of the raffinate dry solids. The macroporous adsorption resin is one of DM30, LX-T81 or LX-T28.

4. The process for simultaneously preparing baicalin, baicalin glycosides, and baicalein flavonoids as described in claim 3, characterized in that: The eluent is thermally concentrated and desolventized at a temperature of 60-90℃ and a pressure of -0.04 to -0.1 MPa until the solid content is 25-55 wt%. Then, it is spray-dried at an inlet temperature of 165-190℃ and an outlet temperature of 70-95℃ to obtain the Scutellaria baicalensis polysaccharide product.

5. The process for simultaneously preparing baicalein, baicalin, and baicalein flavonoids as described in claim 1, characterized in that: The pH of the concentrate in step S3, the primary raffinate in step S4, solution one in step S6, and solution two in step S8 is adjusted using 1-40 wt% hydrochloric acid solution, 1-40 wt% phosphoric acid solution, or 1-40 wt% sulfuric acid solution.

6. The process for simultaneously preparing baicalin, baicalin glycosides, and baicalein flavonoids as described in claim 1, characterized in that: The nanofiltration membrane in step S9 has a molecular weight cutoff of 400-1000 Da.

7. The process for simultaneously preparing baicalin, baicalin glycosides, and baicalein flavonoids as described in claim 1, characterized in that: Step S9: Adjust the pH using 5-40 wt% NaOH solution, 5-40 wt% KOH solution, or 10-60 wt% ammonia solution.

8. The process for simultaneously preparing baicalin, baicalin glycoside, and baicalein flavonoids as described in claim 1, characterized in that: In step S9, the nanofiltration permeate is reused in the extraction water in step S1.

9. The process for simultaneously preparing baicalin, baicalin glycosides, and baicalein flavonoids as described in claim 1, characterized in that: In step S10, the nanofiltration concentrate is concentrated at a temperature of 60-90℃ and a pressure of -0.04 to -0.1 MPa until the solid content is 25-55 wt%. Then, it is spray-dried at an inlet temperature of 165-190℃ and an outlet temperature of 70-95℃ to obtain scutellaria baicalensis flavonoids.

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