Preparation method and application of water-soluble plant extract for cosmetics

Abstract

The invention discloses a preparation method and application of a water-soluble plant extract for cosmetics, and belongs to the technical field of biology. The preparation method comprises the following steps: mixing glycyrrhizic acid and a hydrophobic plant extract according to a molar mass ratio of (10-12): 1, adding 5-7 times by mass of absolute ethyl alcohol, heating and stirring, and concentrating under reduced pressure until concentrated feed liquid is in a semi-solid state; adding 5-10 times by mass of nicotinamide into the concentrated feed liquid, supplementing 10-20 times by mass of water, heating and stirring again, filtering under reduced pressure, drying and crushing to obtain the water-soluble plant extract. Experiments prove that the coating rate of the glycyrrhizic acid and the hydrophobic plant extract can be greatly increased by changing the solvent in which the hydrophobic plant extract reacts with the glycyrrhizic acid, and meanwhile, the assembled molecules can be sealed by adding nicotinamide later, so that the stability of the assembled molecules in normal-temperature water is greatly improved, and the subsequent application risk of the assembled molecules is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of biotechnology, in particular to a preparation method of a water-soluble plant extract for cosmetics and application thereof. BACKGROUND

[0002] In recent years, plant extracts (such as baicalein, silymarin, and zanthoxylum bungeanum masticin) have attracted much attention due to their biological activities such as antioxidant and anti-inflammatory. However, more than 80% of natural active ingredients have poor water solubility (usually <0.1 mg / mL) due to inherent hydrophobicity, which seriously restricts their application in water-based cosmetics, functional drinks, or medicines. Traditional solubilization techniques (such as cyclodextrin inclusion and liposome encapsulation) have complex processes or problems such as organic solvent residues due to the use of chemical synthesis, which cannot meet the demand of green manufacturing such as all-natural sources.

[0003] Glycyrrhizic acid (GA) is an amphiphilic natural triterpenoid saponin that can spontaneously form nanomicelles through intermolecular hydrogen bonds and hydrophobic interactions, providing a new approach for the solubilization of hydrophobic molecules. Existing technologies have confirmed that the evaporation of solvent after the co-dissolution of GA and hydrophobic molecules in ethanol at a specific ratio can form micelles with a particle size of 50-200 nm, which can increase the apparent solubility of silymarin and other components by 20-50 times. However, this technical route has two key defects: (1) thermodynamic metastability of micelles: the self-assembly process relies on non-covalent interactions, and the micelles are prone to dissociation or aggregation under temperature fluctuations (>40℃), pH changes (>7.0), or increased ionic strength, leading to burst release or precipitation of active ingredients; (2) lack of long-term stability verification: existing studies mainly focus on the initial encapsulation efficiency and in vitro release curve of micelles, and lack systematic evaluation of key parameters such as particle size change rate and sedimentation amount during long-term storage (>30 days) in aqueous solution.

[0004] To improve the stability of the self-assembly system, existing technologies have tried the following solutions: (1) metal ion cross-linking method: forming a network structure by coordinating Cu 2+ divalent metal ions with GA carboxyl groups, which can prolong the half-life of micelles, but the residual risk of heavy metals does not meet the safety standards of cosmetics; (2) protein complexing technology: introducing soy protein, whey protein, and other proteins to enhance the density of micelles through hydrophobic interactions, but proteins are prone to denaturation and inactivation, and increase the risk of allergens; (3) synthetic polymer modification: using poly lactic-co-glycolic acid (PLGA) and other materials to coat GA micelles, which increases the preparation cost by 30%-50%, and the degradation products may change the pH of the system.

[0005] The above methods do not fundamentally solve the stability contradiction of glycyrrhizin self-assembly in a complex water environment, especially it is difficult to balance the multiple requirements of safety, cost and sensory characteristics in the field of cosmetics and other fields. Therefore, developing a green and low-cost micelle stabilization strategy has become a key breakthrough for the industrialization of natural product water-solubilization technology. SUMMARY

[0006] The purpose of the present application is to provide a preparation method of water-soluble plant extract for cosmetics and its application, to solve the problems existing in the prior art, the water-soluble plant extract prepared by the present application has excellent water-solubility and embedding rate, compared with the traditional self-assembly method, the embedding rate can be increased by more than 1 times, and the stability of its application in water can be greatly improved by adding nicotinamide at a specific time, reducing product precipitation, making its application more widely.

[0007] To achieve the above purpose, the present application provides the following scheme:

[0008] The present application provides a preparation method of water-soluble plant extract, comprising the following steps:

[0009] Mixing glycyrrhizin and hydrophobic plant extract at a molar mass ratio of (10-12):1, adding 5-7 times the mass of anhydrous ethanol for heating and stirring, and concentrating under reduced pressure to semi-solid concentrate liquid;

[0010] Adding 5-10 times the mass of nicotinamide to the concentrate liquid, adding 10-20 times the mass of water, heating and stirring again, filtering under reduced pressure, drying, and crushing to obtain the water-soluble plant extract.

[0011] Preferably, glycyrrhizin and hydrophobic plant extract are mixed at a molar mass ratio of 12:1, 5 times the mass of anhydrous ethanol is added for heating and stirring, and the concentrate liquid is concentrated under reduced pressure to semi-solid.

[0012] Adding 8 times the mass of nicotinamide to the concentrate liquid, adding 15 times the mass of water, heating and stirring again, filtering under reduced pressure, drying, and crushing to obtain the water-soluble plant extract.

[0013] Preferably, the temperature of the heating and stirring is 70℃.

[0014] Preferably, the conditions for the second heating and stirring are stirring at 70℃ for 2 hours.

[0015] Preferably, the crushed product is sieved through an 80-mesh sieve.

[0016] Optionally, the hydrophobic plant extract includes baicalein, silymarin, zanthoxylin and kava lactone.

[0017] The application also provides a water-soluble plant extract prepared by the preparation method.

[0018] The application also provides application of the water-soluble plant extract in preparation of cosmetics.

[0019] Optionally, the cosmetics include non-efficiency cosmetics and efficiency cosmetics.

[0020] The application also provides application of the water-soluble plant extract in preparation of medicines.

[0021] The application discloses the following technical effects:

[0022] The application uses anhydrous ethanol heating and stirring reaction, can effectively collide between molecules of glycyrrhizin and hydrophobic plant extracts, greatly improves the wrapping rate, and finally provides the water-soluble plant extract which solves the problems of poor water solubility of the hydrophobic plant extract at room temperature and poor water solution stability, and provides a new preparation method of the water-soluble plant extract.

[0023] It is verified through experiments that by changing the solvent reacted by the hydrophobic plant extract and glycyrrhizin, the wrapping rate of glycyrrhizin and the hydrophobic plant extract can be greatly increased, and by adding nicotinamide later, the assembled molecules can be sealed, the stability of the assembled molecules in water at room temperature is greatly improved, and the subsequent application risk is reduced.

[0024] The water-soluble plant extract prepared by the application has excellent water solubility and embedding rate, compared with the traditional self-assembly method, the embedding rate can be increased by more than 1 times, and the stability of the water-soluble plant extract in water can be greatly improved by adding nicotinamide at a specific time, the product precipitation is reduced, and the application is more extensive. BRIEF DESCRIPTION OF DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, the following will briefly introduce the drawings needed in the embodiments. Obviously, the drawings in the following description only constitute some embodiments of the application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

[0026] Figure 1 Picture of 1% water solution of the water-soluble baicalein product of Example 1 placed for 30 days;

[0027] Figure 2 Picture of 1% water solution of the water-soluble kaurenoic acid product of Example 4 placed for 30 days;

[0028] Figure 3 Liquid chromatogram of the water-soluble baicalein product of Example 1;

[0029] Figure 4 Liquid chromatogram of the water-soluble kavalactone product obtained in Example 4. DETAILED DESCRIPTION

[0030] The following detailed description of various example embodiments of the application is not to be considered limiting of the scope or spirit of the application, but rather as a description of its some aspects, features and embodiments.

[0031] It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. In addition, where particular ranges of values are given, understand that each intervening value, to the upper or lower limit of the ranges is also specifically included. Each smaller range that falls within the broader ranges is also specifically included. The upper and lower limits of these smaller ranges can independently be included or excluded in the range.

[0032] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. Although preferred methods and materials are described, any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present application. All documents mentioned herein are incorporated by reference to disclose and describe the methods and / or materials in connection with which the documents are cited. In case of conflict, the present specification will control.

[0033] Various modifications and changes can be made to the specific embodiments of the present application described herein without departing from the scope or spirit of the application. Other embodiments of the application will be apparent to those of ordinary skill in the art from the description and examples presented herein. The description and examples are illustrative of the application and are not intended to limit the scope of the application in any way.

[0034] As used herein, the terms "comprise", "comprising", "include", "including", "have", "having" and the like are open-ended and do not exclude additional elements or steps.

[0035] The prior art reports the preparation of water-soluble substances using glycyrrhizinic acid self-assembly: CN118649144A 6-gingerol-glycyrrhizinic acid self-assembly nanoparticle preparation method discloses dissolving 6-gingerol in ethanol as an organic phase; under water bath heating conditions, dispersing glycyrrhizinic acid in ultrapure water, stirring to clarify as an aqueous phase; dropwise adding the obtained organic phase to the obtained aqueous phase, stirring under water bath heating conditions, then cooling to room temperature, ultrasonic dispersion, rotary evaporation to remove ethanol, centrifugation to obtain the supernatant, to obtain 6-gingerol-glycyrrhizinic acid self-assembly nanoparticles. It lacks long-term stability verification, and does not record how to improve the stability of glycyrrhizinic acid self-assembly nanoparticles.

[0036] The prior art reports the preparation of water-soluble substances by self-assembly of glycyrrhizic acid: CN117752614A, a kind of astragalus glycoside / glycyrrhizic acid self-assembly nanomedicine and preparation method and application, the method for preparing astragalus glycoside / glycyrrhizic acid self-assembly nanomedicine, comprising: S1, dissolving astragalus glycoside in organic solvent to obtain astragalus glycoside solution A; S2, glycyrrhizic acid is dissolved in the same organic solvent as step S1 to obtain glycyrrhizic acid solution B; S3, the astragalus glycoside solution A obtained in step S1 and the glycyrrhizic acid solution B obtained in step S2 are mixed in a ratio of 1:1, ultrasonic mixing is carried out to make the mixture uniform, and then magnetic stirring is carried out to obtain a mixed solution C of astragalus glycoside / glycyrrhizic acid; S4, the mixed solution C of astragalus glycoside / glycyrrhizic acid obtained in step S3 is added to 9 times the volume of ultrapure water according to the volume ratio of 1:9, and after the reaction is completed, dialysis purification and centrifugal precipitation are carried out, and the supernatant solution obtained is the astragalus glycoside / glycyrrhizic acid self-assembly nanomedicine. It also lacks long-term stability verification, and how to improve the stability of glycyrrhizic acid self-assembly nanoparticles is not recorded.

[0037] The prior art reports the preparation of water-soluble substances by self-assembly of glycyrrhizic acid: CN118949256A A glycyrrhizic acid / panthenol binary liquid supramolecular self-assembly system and its preparation method, the method for preparing the glycyrrhizic acid / panthenol binary liquid supramolecular self-assembly system comprises the following steps: heating panthenol in air or inert gas at 50-80℃ for 1.5h, then mixing with glycyrrhizic acid according to the molar ratio (0.01-0.1):0.001, continuing to heat at 50-80℃ in air or inert gas for 1.5h, reducing to room temperature, ultrasonic, preparing the glycyrrhizic acid / panthenol binary liquid supramolecular self-assembly system. And it is disclosed that: the glycyrrhizic acid / panthenol system obtained by supramolecular self-assembly is stable in liquid state, can be mixed with water of a certain proportion without precipitation, and can effectively improve the water solubility, antibacterial property and stability of glycyrrhizic acid. Specifically: (1) the glycyrrhizic acid / panthenol binary liquid system prepared by the supramolecular self-assembly technology of the present application is uniform, transparent and stable, and the content of glycyrrhizic acid in the system can be as high as 25%, which is much higher than the actual application concentration of glycyrrhizic acid, providing sufficient adjustment space for subsequent formulation application. (2) The glycyrrhizic acid / panthenol binary liquid supramolecular self-assembly system prepared by the present application significantly enhances the water solubility of glycyrrhizic acid, can be mutually soluble with water, and the mass fraction of glycyrrhizic acid after mutual solubility can be as high as 20%, without any solid glycyrrhizic acid particles precipitating. (3) The glycyrrhizic acid / panthenol binary liquid supramolecular self-assembly system prepared by the present application is low in viscosity and transparent, can be directly used as raw material, can maintain long-term stability, and performs excellently in formulation application and product efficacy. (4) The preparation method of the glycyrrhizic acid / panthenol binary liquid supramolecular self-assembly system adopted by the present application is green, simple, mild in conditions, and the obtained system can be directly applied without separation and purification and other post-treatment. In summary, the glycyrrhizic acid / panthenol binary liquid supramolecular self-assembly system and its preparation method of the present application have the characteristics of green environmental protection, simple process, and can significantly improve the water solubility and stability of glycyrrhizic acid. The present application selects suitable compatible components, so that the glycyrrhizic acid shows more excellent performance in raw materials or formulations, which is of great significance for the application of glycyrrhizic acid, and can expand its wide application in the field of cosmetics. It can be seen that this patent adopts the compatibility of glycyrrhizic acid and panthenol to improve the water solubility, antibacterial property and stability of glycyrrhizic acid.

[0038] Example 1

[0039] A preparation method of a water-soluble plant extract, comprising the following steps:

[0040] (1) First reaction of raw materials: mix glycyrrhizic acid and hydrophobic plant extract baicalein according to the molar mass ratio of 12:1. Add 5 times the mass of anhydrous ethanol. Heat and stir at 70℃ until the solution is clear and transparent.

[0041] (2) Concentration under reduced pressure: remove anhydrous ethanol by concentration under reduced pressure, and supplement water during the concentration process until the concentrated liquid is semisolid.

[0042] (3) Water replenishment and secondary feeding reaction: 8 times mass of nicotinamide (relative to the mass of baicalein) was added to the concentrated solution. Then 15 times mass of pure water (relative to the total mass of nicotinamide + glycyrrhizic acid + baicalein) was added. The reaction was stirred at 70°C for 2 hours.

[0043] (4) Vacuum filtration: The concentrated solution was filtered under vacuum (to remove insoluble substances / large particles).

[0044] (5) Drying: The filtrate was spray-dried, and the final product was obtained by crushing through an 80-mesh sieve.

[0045] A 1% aqueous solution of the water-soluble baicalein product was prepared, and the results after 30 days of storage are shown in FIG. 1. As can be seen, the aqueous solution was clear and transparent, and no obvious precipitate was observed after 30 days of storage. Figure 1

[0046] The water-soluble baicalein product was subjected to liquid chromatography detection, and the results are shown in FIG. 2. As can be seen, there was a baicalein absorption peak at the fixed peak time. Figure 3

[0047] Example 2

[0048] A method for preparing a water-soluble plant extract, comprising the following steps:

[0049] (1) Primary reaction of raw materials: Glycyrrhizic acid and hydrophobic plant extract silymarin were mixed at a molar mass ratio of 12:1. 6 times mass of anhydrous ethanol was added. The solution was heated and stirred at 70°C until it was clear and transparent.

[0050] (2) Vacuum concentration: Anhydrous ethanol was removed by vacuum concentration, and water was added during the concentration process until the concentrated solution was semi-solid.

[0051] (3) Water replenishment and secondary feeding reaction: 5 times mass of nicotinamide (relative to the mass of silymarin) was added to the concentrated solution. Then 10 times mass of pure water (relative to the total mass of nicotinamide + glycyrrhizic acid + silymarin) was added. The reaction was stirred at 65°C for 2.5 hours.

[0052] (4) Vacuum filtration: The concentrated solution was filtered under vacuum (to remove insoluble substances / large particles).

[0053] (5) Drying: The filtrate was spray-dried, and the final product was obtained by crushing through an 80-mesh sieve.

[0054] Example 3

[0055] A method for preparing a water-soluble plant extract, comprising the following steps:

[0056] ​​(1) First reaction of raw materials: Licorice acid and hydrophobic plant extract, piperlongumine, were mixed at a molar mass ratio of 11:1. 5 times the mass of anhydrous ethanol was added. Stirring was performed at 70°C until the solution was clear and transparent.

[0057] (2) Concentration under reduced pressure: Anhydrous ethanol was removed by concentration under reduced pressure, and water was added during the concentration process until the concentrated solution was semi-solid.

[0058] (3) Second reaction of raw materials after water addition: 6 times the mass of nicotinamide (relative to the mass of piperlongumine) was added to the concentrated solution. Then, 17 times the mass of pure water (relative to the total mass of nicotinamide + licorice acid + piperlongumine) was added. Stirring was performed at 75°C for 2 hours.

[0059] (4) Filtration under reduced pressure: Filtration was performed under reduced pressure using medium-speed filter paper (to remove insoluble substances / large particles).

[0060] (5) Drying: The filtrate was spray-dried, and the final water-soluble piperlongumine product was obtained by crushing through an 80-mesh sieve.

[0061] Example 4

[0062] A method for preparing a water-soluble plant extract, comprising the following steps:

[0063] First reaction of raw materials: Licorice acid and hydrophobic plant extract, kavalactone, were mixed at a molar mass ratio of 10:1. 7 times the mass of anhydrous ethanol was added. Stirring was performed at 70°C until the solution was clear and transparent.

[0064] (2) Concentration under reduced pressure: Anhydrous ethanol was removed by concentration under reduced pressure, and water was added during the concentration process until the concentrated solution was semi-solid.

[0065] (3) Second reaction of raw materials after water addition: 10 times the mass of nicotinamide (relative to the mass of kavalactone) was added to the concentrated solution. Then, 20 times the mass of pure water (relative to the total mass of nicotinamide + licorice acid + kavalactone) was added. Stirring was performed at 70°C for 2 hours.

[0066] (4) Filtration under reduced pressure: Filtration was performed under reduced pressure using medium-speed filter paper (to remove insoluble substances / large particles).

[0067] (5) Drying: The filtrate was spray-dried, and the final water-soluble kavalactone product was obtained by crushing through an 80-mesh sieve.

[0068] A 1% aqueous solution of the water-soluble kavalactone product was prepared, and the results after 30 days of storage are shown in Figure 2 It can be seen that after 30 days of storage, the aqueous solution was clear and transparent, and there was no obvious precipitation.

[0069] Liquid chromatography was performed on the water-soluble kavalactone product, and the results are shown in Figure 4As shown, it can be seen that there are six components of kava lactone absorption peaks in the fixed peak time.

[0070] Comparative Example 1

[0071] A method for preparing a water-soluble plant extract is the same as in Example 1, except that anhydrous ethanol is replaced by 50% ethanol. Details are as follows.

[0072] (1) Primary reaction of raw materials: Glycyrrhizin and hydrophobic plant extract baicalein were mixed in a molar mass ratio of 12:1. 5 times the mass of 50% ethanol (volume fraction) was added. Stirring was performed at 70°C for 1 hour (due to changes in alcohol concentration, it was difficult to achieve a solution stirring to a clear and transparent state).

[0073] (2) Concentration under reduced pressure: 50% ethanol was removed by concentration under reduced pressure, and water was supplemented during the concentration process until the concentrated liquid was semi-solid.

[0074] (3) Secondary feeding reaction with water supplementation: 8 times the mass of nicotinamide (relative to the mass of baicalein) was added to the concentrated liquid. Then 15 times the mass of pure water (relative to the total mass of nicotinamide + glycyrrhizin + baicalein) was supplemented. Stirring was performed at 70°C for 2 hours.

[0075] (4) Filtration under reduced pressure: Filtration was performed under reduced pressure using medium-speed filter paper (to remove insoluble matter / large particles).

[0076] (5) Drying: The filtrate was spray-dried, and the final water-soluble baicalein product was obtained by crushing through an 80-mesh sieve.

[0077] Comparative Example 2

[0078] A method for preparing a water-soluble plant extract is the same as in Example 1, except that anhydrous ethanol is replaced by 75% ethanol. Details are as follows.

[0079] (1) Primary reaction of raw materials: Glycyrrhizin and hydrophobic plant extract baicalein were mixed in a molar mass ratio of 12:1. 5 times the mass of 75% ethanol (volume fraction) was added. Stirring was performed at 70°C for 1 hour (due to changes in alcohol concentration, it was difficult to achieve a solution stirring to a clear and transparent state).

[0080] (2) Concentration under reduced pressure: 75% ethanol was removed by concentration under reduced pressure, and water was supplemented during the concentration process until the concentrated liquid was semi-solid.

[0081] (3) Secondary feeding reaction with water supplementation: 8 times the mass of nicotinamide (relative to the mass of baicalein) was added to the concentrated liquid. Then 15 times the mass of pure water (relative to the total mass of nicotinamide + glycyrrhizin + baicalein) was supplemented. Stirring was performed at 70°C for 2 hours.

[0082] (4) Vacuum filtration: filter the filtrate under vacuum (remove insoluble matter / large particles).

[0083] (5) Drying: spray dry the filtrate, and pulverize through an 80 mesh screen to obtain the final water-soluble baicalein product.

[0084] Comparative Example 3

[0085] A method for preparing a water-soluble plant extract, which is identical to Example 1, except that no nicotinamide is added during the second feeding reaction. Details are as follows.

[0086] A method for preparing a water-soluble plant extract, which comprises the following steps:

[0087] (1) First reaction of raw materials: mix glycyrrhizin and hydrophobic plant extract baicalein at a molar mass ratio of 12:1. Add 5 times the mass of anhydrous ethanol. Heat and stir at 70°C until the solution is clear and transparent.

[0088] (2) Vacuum concentration: remove the anhydrous ethanol by vacuum concentration, and supplement water during the concentration process until the concentrated solution is semi-solid.

[0089] (3) Second feeding reaction with water: supplement 15 times the mass of pure water (relative to the total mass of glycyrrhizin + baicalein) to the concentrated solution. Stir and react at 70°C for 2 hours.

[0090] (4) Vacuum filtration: filter the filtrate under vacuum (remove insoluble matter / large particles).

[0091] (5) Drying: spray dry the filtrate, and pulverize through an 80 mesh screen to obtain the final water-soluble baicalein product.

[0092] Comparative Example 4

[0093] A method for preparing a water-soluble plant extract, which is identical to Example 1, except that nicotinamide is added after the completion of the stirring reaction. Details are as follows.

[0094] (1) First reaction of raw materials: mix glycyrrhizin and hydrophobic plant extract baicalein at a molar mass ratio of 12:1. Add 5 times the mass of anhydrous ethanol. Heat and stir at 70°C until the solution is clear and transparent.

[0095] (2) Vacuum concentration: remove the anhydrous ethanol by vacuum concentration, and supplement water during the concentration process until the concentrated solution is semi-solid.

[0096] (3) Second feeding reaction with water: supplement 15 times the mass of pure water (relative to the total mass of glycyrrhizin + baicalein). Stir and react at 70°C for 2 hours, and then add 8 times the mass of nicotinamide (relative to the mass of baicalein).

[0097] (4) Vacuum filtration: filter the filtrate under vacuum (remove insoluble substances / large particles).

[0098] (5) Drying: spray dry the filtrate, crush through an 80 mesh screen to obtain the final water-soluble baicalein product.

[0099] Comparative Example 5

[0100] The conventional water self-assembly method was used, as follows.

[0101] A method for preparing a water-soluble plant extract, comprising the following steps:

[0102] (1) First reaction of raw materials: the appropriate amount of glycyrrhizic acid and hydrophobic plant extract baicalein were weighed according to a molar mass ratio of 12:1. Glycyrrhizic acid was added to 5 times the amount of purified water, and heated and stirred at 70°C until the solution was clear and transparent; baicalein was added to 5 times the mass of anhydrous ethanol. Heat and stir at 70°C until the solution is clear and transparent, and slowly add the baicalein alcohol solution to the stirred glycyrrhizic acid aqueous solution, and heat and stir at 70°C for 1 hour.

[0103] (2) Vacuum concentration: remove the anhydrous ethanol by vacuum concentration, and supplement water during the concentration process until the concentrated solution is semi-solid.

[0104] (3) Second reaction of raw materials: supplement 15 times the mass of purified water (relative to the total mass of glycyrrhizic acid + baicalein) to the concentrated solution. Stir and react at 70°C for 2 hours.

[0105] (4) Vacuum filtration: filter the filtrate under vacuum (remove insoluble substances / large particles).

[0106] (5) Drying: spray dry the filtrate, crush through an 80 mesh screen to obtain the final water-soluble baicalein product.

[0107] Verification Example

[0108] The embedding rate, water solubility, precipitation rate after 30 days (45°C), and transdermal rate of Examples 1-4 and Comparative Examples 1-5 were detected, and the results are shown in Table 1.

[0109] Specifically, the calculation formula of the embedding rate E (%) is:

[0110] Wherein, m1: the mass of the final water-soluble plant extract obtained in the example or comparative example;

[0111] X1: the content of the active ingredient in the final water-soluble plant extract obtained in the example or comparative example;

[0112] m2: the mass of the hydrophobic plant extract used in the reaction of the example or comparative example;

[0113] X2: the effective component content of the hydrophobic plant extract used in the reaction of the example or the comparative example;

[0114] The water solubility was tested according to the regulation in the first part of the Pharmacopoeia of the People's Republic of China 2020 edition under the item 20 of the general rules.

[0115] The precipitation rate detection method for 30 days (45 DEG C) placement: 1% aqueous solution was prepared, and after being placed for 30 days at room temperature, the precipitate was obtained by high-speed centrifugation at 10000 r / min, and after air drying, the precipitation rate was calculated according to the following formula:

[0116]

[0117] The transdermal rate detection method: according to GB / T 27818-2011 Chemicals Skin Absorption In Vitro Test Method, the final transdermal rate calculation formula is:

[0118] Table 1: embedding rate, water solubility, 30-day precipitation rate and transdermal rate of each group

[0119]

[0120]

[0121] Note: different letters in each column represent that the difference is statistically significant (p<0.05).

[0122] As can be seen from Table 1, the water-soluble plant extracts prepared in Examples 1-4 of the present application all have good effects, high embedding rate, strong water solubility and high transdermal rate. The effects of Comparative Example 1 using 50% ethanol and Comparative Example 2 using 75% ethanol are far inferior to Example 1; the 30-day precipitation rate of Comparative Example 3 is 34% because no nicotinamide is added, and the stability is significantly inferior to Example 1; although Comparative Example 4 adds nicotinamide, it is added after the stirring reaction, and cannot play the effect of timely “sealing”, the hydrophobic plant extract component has been continuously precipitated at this reaction stage, resulting in a significant reduction in the embedding rate of the product, so the effect of Comparative Example 4 is also significantly inferior to Example 1; and Comparative Example 5 uses a conventional water self-assembly method, obviously, its embedding effect is significantly inferior to Example 1. In summary, the operations in the method for preparing the water-soluble plant extract provided by the present application are mutually coordinated and indispensable, only the water-soluble plant extract prepared by the method provided by the present application has the above-mentioned effects.

[0123] The above-described examples only describe the preferred modes of the present application, and do not limit the scope of the present application, and various modifications and improvements to the technical solutions of the present application made by those skilled in the art without departing from the design spirit of the present application shall fall within the protection scope determined by the claims of the present application.

Claims

1. A method for preparing a water-soluble plant extract, characterized in that, Includes the following steps: Glycyrrhizic acid and hydrophobic plant extract were mixed at a molar mass ratio of (10-12):1, and 5-7 times the mass of anhydrous ethanol was added. The mixture was heated and stirred, and then concentrated under reduced pressure until the concentrated liquid was semi-solid. Add 5-10 times the weight of nicotinamide to the concentrated liquid, then add 10-20 times the weight of water, heat and stir again, and then filter under reduced pressure, dry and pulverize to obtain the water-soluble plant extract.

2. The preparation method according to claim 1, characterized in that, Glycyrrhizic acid and hydrophobic plant extract were mixed at a molar mass ratio of 12:1, and 5 times the mass of anhydrous ethanol was added. The mixture was heated and stirred, and then concentrated under reduced pressure until the concentrated liquid was semi-solid. Add 8 parts by weight of nicotinamide to the concentrated liquid, then add 15 parts by weight of water, heat and stir again, and then filter under reduced pressure, dry and pulverize to obtain the water-soluble plant extract.

3. The preparation method according to claim 1, characterized in that, The heating and stirring temperature is 70°C.

4. The preparation method according to claim 1, characterized in that, The conditions for reheating and stirring are: stirring at 70°C for 2 hours.

5. The preparation method according to claim 1, characterized in that, The powder is then passed through an 80-mesh sieve.

6. The preparation method according to claim 1, characterized in that, The hydrophobic plant extracts include baicalin, silymarin, zanthoxylin and calvanolide.

7. The water-soluble plant extract prepared by the preparation method according to any one of claims 1-6.

8. The application of the water-soluble plant extract as described in claim 7 in the preparation of cosmetics.

9. The application as described in claim 8, characterized in that, The cosmetics mentioned include non-functional cosmetics and functional cosmetics.

10. The use of the water-soluble plant extract as described in claim 7 in the preparation of a pharmaceutical product.

Images