A pickering emulsion based on stachys asiatica extract and a method of preparing the same

Abstract

The application discloses a Pickering emulsion based on extract of Herba Rehmanniae and a preparation method thereof. The Pickering emulsion only uses the extract of Herba Rehmanniae as a stabilizer, and does not need to add emulsifiers, surfactants and other modifiers. The Pickering emulsion preparation method comprises the following steps: preparing the extract of Herba Rehmanniae by using a pressurized hot water method; and mixing the extract aqueous solution with an oil phase, and then performing heating and stirring treatment to obtain the Pickering emulsion. The Pickering emulsion has the advantages of good biocompatibility, biodegradability and low toxicity, and can be used as a delivery system in the food, medicine and cosmetic industries, can load fat-soluble functional components, and can realize multiple utilities. The preparation method of the emulsion is simple, the operation conditions are mild and controllable, and industrialized production popularization can be easily realized.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of pharmaceutical preparation, and particularly relates to a Pickering emulsion with extract of Herba Epimedii as stabilizer and a preparation method thereof. BACKGROUND

[0002] An emulsion is a homogeneous mixed dispersion system composed of two mutually insoluble liquids, and therefore the emulsion is a thermodynamically unstable system, and has high surface energy between the two phases, and thus a surfactant needs to be added to maintain the stability of the system. The Pickering emulsion is a kind of emulsion with solid particles as stabilizer instead of surfactant. Compared with the traditional emulsion, the Pickering emulsion has the following advantages: (1) the amount of solid particle stabilizer is small, which saves raw materials and reduces cost; (2) there is no surfactant additive, which is friendly to human body and environment, and especially the food-grade solid particles have good biocompatibility and low toxicity; (3) the influence of external environmental factors on the emulsion is small, and the stability is stronger. Therefore, the preparation of Pickering emulsion and the application research in the fields of food hygiene, biological medicine and cosmetics are concerned.

[0003] The stabilizers of the existing Pickering emulsion are mainly divided into inorganic solid particles and organic solid particles. The Pickering emulsion with inorganic particles such as silicon dioxide and graphene as stabilizer has good stability, and is often used in the production of industrial products. Since the biocompatibility of inorganic solid particles is poor, the Pickering emulsion is more inclined to use biocompatible organic solid particles of biological origin when used in the fields of food, medicine and cosmetics. The biological source particles as the stabilizer of the Pickering emulsion mainly include the following: polysaccharides such as chitosan and cyclodextrin; proteins such as zein and soybean protein isolate; and some biological small molecule active ingredients such as flavones, saponins and phytosterols. The biological source solid particles have good biocompatibility and biodegradability, and have low toxic side effects when applied to the body, so the development prospect is very broad, but screening suitable biological source stabilizer has been a bottleneck in the development of this type of product. Traditional Chinese medicine contains various bioactive ingredients, and the complex structure skeleton and rich functional groups of these ingredients endow them with structural and functional diversity, so traditional Chinese medicinal materials are an important source for finding and discovering suitable biological-based solid particles. SUMMARY

[0004] The purpose of the present application is to provide a Pickering emulsion and a preparation method thereof, the emulsion of which only uses the extract of Herba Epimedii as stabilizer, the emulsion preparation method is simple, the stability is high, and the emulsion can be used for loading fat-soluble ingredients.

[0005] The purpose of the present application is achieved by the following technical solutions:

[0006] First, take a dry Stachys asiatica Nakai medicinal material, according to the proportion of deionized water soaked for a period of time.

[0007] Then transfer to the pressure extractor, pressurized to 0.1-1.0MPa, temperature control at 100-150℃, 10-60min.

[0008] After the extraction is completed, the extraction liquid is sprayed from the sampling port, filtered, placed in a 4℃ refrigerator, and ready for use.

[0009] Take the Stachys asiatica Nakai extract, add oil phase according to the proportion, heat and stir at 30-70℃ until the water phase and oil phase are mixed into a uniform emulsion, and cool to room temperature.

[0010] In the preparation method described above, the Stachys asiatica Nakai used is Stachys asiatica Nakai or fried Stachys asiatica Nakai, and the preferred is fried Stachys asiatica Nakai.

[0011] In the preparation method described above, the ratio of Stachys asiatica Nakai to deionized water is 1:7-50, preferably 1:10-20.

[0012] In the preparation method described above, the oil phase used includes but is not limited to one or more of corn oil, peanut oil, soybean oil, sesame oil and cinnamon essential oil.

[0013] In the preparation method described above, the ratio of Stachys asiatica Nakai extract to oil phase is 10:1-1:1, preferably 10:4-1:1.

[0014] In the preparation method described above, the stirring speed is 100-1000r / min, preferably 500r / min.

[0015] Compared with the prior art, the Pickering emulsion prepared by the present application has the following characteristics: first, the water extract of Stachys asiatica Nakai as a stabilizer has good biocompatibility and can be used in food, medicine and cosmetics industries; second, only the water extract of Stachys asiatica Nakai is used as a stabilizer, without the need for additional emulsifiers, surfactants and other modifiers, it has good storage stability; third, the preparation method of Stachys asiatica Nakai extract is green and environmentally friendly, no organic solvents are used, the production cost is low, and there is no pollution to the environment; fourth, it can be prepared into emulsion gel, which is more convenient for transportation and use; fifth, it can be used to load fat-soluble ingredients to improve the transmembrane transport performance; sixth, the preparation process is simple, the operation conditions are mild and controllable, and it is easy to realize industrialized production and popularization. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 Pickering emulsion (Example 2) physical state diagram.

[0017] Figure 2 Physical state diagram of Pickering emulsion gel (Example 5).

[0018] Figure 3 Optical microscope images (40x magnification). A. Corn oil-based Pickering emulsion (Example 2); B. Cinnamon oil-based Pickering emulsion (Example 4); C. Corn oil-based emulsion gel (Example 5).

[0019] Figure 4 Optical fluorescence microscopy images (200 μm) of pickering emulsions. A. Cinnamon oil-based pickering emulsion (Example 4); B. Corn oil-based pickering emulsion (Example 2).

[0020] Figure 5 Physical state diagram of Pickering milk (Example 2) diluted at different ratios and left for 30 days.

[0021] Figure 6 Curcumin release curve. 1. Curcumin raw material; 2. Curcumin-loaded Pickering emulsion. Detailed implementation method:

[0022] The present invention will be further described in detail below with reference to embodiments. It should be understood that these embodiments are merely illustrative and not intended to limit the scope of the invention in any way. Unless otherwise specified, the terminology used in this invention generally has the meaning commonly understood by those skilled in the art. Any method, process, or product that conforms to the description in the claims or specification and meets the principles, novelty, and inventiveness disclosed herein falls within the protection scope of this invention.

[0023] Example 1:

[0024] Take an appropriate amount of dried raw Wangbuliuxing medicinal material and soak it in deionized water at a ratio of 1:7 for a certain period of time.

[0025] Then transfer it to a pressure extractor, pressurize it to 0.5 MPa, control the temperature at 120℃, and maintain the temperature and pressure for 30 minutes;

[0026] After complete extraction, spray the extract through the sampling tube, filter it, and refrigerate it at 4°C for later use.

[0027] Take an appropriate amount of Vaccaria segetalis extract and add peanut oil in a 1:1 ratio. Heat and stir at 30°C and 500 r / min until the aqueous phase and oil phase are mixed into a uniform emulsion. Cool to room temperature to obtain peanut oil-based Pickering emulsion.

[0028] Example 2:

[0029] Take a suitable amount of dry fried Herba Vaccariae, and soak in deionized water according to the ratio of 1:10 for a certain period of time;

[0030] Then transfer to the pressure extractor, pressurize to 0.5 MPa, control the temperature at 120 DEG C, and keep the temperature and pressure for 20 min;

[0031] After the extraction is completed, the extract is sprayed out through the sampling tube, filtered, and placed in a 4 DEG C refrigerator for cold storage for standby use.

[0032] Take a suitable amount of Herba Vaccariae extract, and add corn oil according to the ratio of 10:9, heat and stir at 40 DEG C and 500 r / min until the water phase and oil phase are mixed into a uniform emulsion, and then cool to room temperature to obtain a corn oil-based Pickering emulsion.

[0033] Example 3

[0034] Take a suitable amount of dry fried Herba Vaccariae, and soak in deionized water according to the ratio of 1:20 for a certain period of time;

[0035] Then transfer to the pressure extractor, pressurize to 0.5 MPa, control the temperature at 130 DEG C, and keep the temperature and pressure for 10 min;

[0036] After the extraction is completed, the extract is sprayed out through the sampling tube, filtered, and placed in a 4 DEG C refrigerator for cold storage for standby use.

[0037] Take a suitable amount of Herba Vaccariae extract, and add sesame oil according to the ratio of 10:8, heat and stir at 50 DEG C and 500 r / min until the water phase and oil phase are mixed into a uniform emulsion, and then cool to room temperature to obtain a sesame oil-based Pickering emulsion.

[0038] Example 4

[0039] Take a suitable amount of dry fried Herba Vaccariae, and soak in deionized water according to the ratio of 1:20 for a certain period of time;

[0040] Then transfer to the pressure extractor, pressurize to 0.5 MPa, control the temperature at 120 DEG C, and keep the temperature and pressure for 20 min;

[0041] After the extraction is completed, the extract is sprayed out through the sampling tube, filtered, and placed in a 4 DEG C refrigerator for cold storage for standby use.

[0042] Take a suitable amount of Herba Vaccariae extract, and add cinnamon essential oil according to the ratio of 10:9, heat and stir at 50 DEG C and 500 r / min until the water phase and oil phase are mixed into a uniform emulsion, and then cool to room temperature to obtain a cinnamon oil-based Pickering emulsion.

[0043] Example 5

[0044] Take a certain amount of dry fried Herba Epimedii, soak in deionized water for a certain period of time according to the ratio of 1:10;

[0045] Then transfer to the pressurized extractor, pressurize to 0.5 MPa, control the temperature at 120℃, extract for 30 min;

[0046] After the extraction is completed, take out the extraction liquid through the sampling tube, filter, and place in the 4℃ refrigerator for cold storage for standby use.

[0047] Take a certain amount of Herba Epimedii extraction liquid, add corn oil according to the ratio of 10:4, heat and stir at 70℃ and 500 r / min until the water phase and oil phase are mixed into a uniform emulsion, continue to heat and stir into a viscous semi-solid, cool to room temperature, and corn oil-based Pickering emulsion gel is obtained.

[0048] Example 6

[0049] Take a certain amount of dry fried Herba Epimedii, soak in deionized water for a certain period of time according to the ratio of 1:20;

[0050] Then transfer to the pressurized extractor, pressurize to 1.0 MPa with an air compressor, control the temperature at 140℃, extract for 10 min;

[0051] After the extraction is completed, take out the extraction liquid through the sampling tube, filter, and place in the 4℃ refrigerator for cold storage for standby use.

[0052] Take a certain amount of Herba Epimedii extraction liquid, add soybean oil according to the ratio of 10:6, heat and stir at 50℃ and 500 r / min until the water phase and oil phase are mixed into a uniform emulsion, cool to room temperature, and soybean oil-based Pickering emulsion is obtained.

[0053] I. Viscosity analysis

[0054] Take a certain amount of the prepared Pickering emulsion and emulsion gel. Insert the viscometer rotor vertically into the liquid surface. Select the reading close to 50% as the viscosity of the emulsion or gel, and record the data of each group.

[0055] Table 1 Viscosity of Pickering emulsion and emulsion gel

[0056]

[0057] The Pickering emulsion is milky white to light yellow emulsion with small viscosity and certain flowability, as shown in Table 1. The viscosity of the Pickering emulsion gel is large, showing a semi-solid state without flowability, as shown in Table 1. Figure 1 Figure 2 ​​

[0058] II. Microstructure analysis

[0059] 1. The microstructure of Pickering emulsion and emulsion gel was observed by optical microscope. The sample was diluted with deionized water, uniformly coated on the glass slide, covered with a cover glass, and observed at 40 times magnification. The morphology of the emulsion was observed, and the morphological photographs were obtained, as shown in Figure 3 From the figure, it can be seen that the droplets in different oil-based Pickering emulsions are uniform in size and evenly distributed. The droplets in corn oil-based Pickering emulsion are larger than those in cinnamon essential oil-based Pickering emulsion, indicating that the oil base can affect the size of the Pickering emulsion droplets. After being prepared into emulsion gel, the droplets are closely arranged, indicating that the three-dimensional network structure formed binds the liquid oil into a semi-solid gel system.

[0060] 2. The Pickering emulsion was diluted with deionized water, then fluorescent sodium solution was added for staining, and then uniformly coated on the glass slide, covered with a cover glass. In the dim environment, the fluorescence microscope was used for observation (see Figure 4 ). Fluorescent sodium is a water-soluble dye, and red represents the water phase. From the fluorescence microscope photos, it can be seen that the Pickering emulsion droplets prepared with two kinds of oil bases are uniform in size and evenly distributed. The cinnamon essential oil-Pickering emulsion forms a water-in-oil emulsion, while the corn oil-Pickering emulsion forms an oil-in-water emulsion.

[0061] III. Investigation of the storage stability of Pickering emulsion

[0062] 5 ml of Pickering emulsion 1, 2, 3, 4, and 5 prepared in Example 2 were taken and diluted with water to 5 ml. The storage stability was investigated by placing them at room temperature for 30 days and shaking several times a day. The results are shown in Figure 5 The Pickering emulsion stock solution and diluted solution have good stability at room temperature and do not show instability phenomena such as demulsification, coalescence, and flocculation. They are basically not affected by external environmental factors.

[0063] IV. Investigation of the drug release behavior of Pickering emulsion

[0064] A certain amount of curcumin was dissolved in corn oil, and Pickering emulsion was prepared according to the method of Example 2. The transdermal absorption rate of curcumin in the Pickering emulsion was detected by the Franz diffusion cell method. Pig intestines were cut into appropriate sizes, fixed, and placed in the diffusion cell. 30% ethanol aqueous solution was used as the receiving liquid, the temperature of the equipment was adjusted to 37°C, and the magnetic stirring was performed at a constant speed of 300 r / min. Samples were taken at 0, 2, 4, 6, 8, 10, and 12 h, 2 ml each time, and 2 ml was supplemented into the receiving cell at the same time. The removed samples were appropriately diluted, and the absorbance was detected at 425 nm by the ultraviolet-visible spectrophotometer. The cumulative release amount Q was calculated. The transdermal absorption curve is shown in Figure 6 It can be seen from the figure that the curcumin loaded in the Pickering emulsion has better transdermal absorption performance than the raw material drug, and the cumulative transdermal rate in 12 hours is 2.5 times that of the raw material drug. It is proved that the Pickering emulsion as a delivery system for fat-soluble components can effectively improve the transdermal absorption rate of such components, thereby improving the bioavailability and improving the efficacy.

Claims

1. A Pickering emulsion based on an extract of Stachys biebersteinii, characterized in that, The preparation method of the Pickering emulsion comprises the following steps: first, an extract of cowslip is prepared by using pressurized hot water method; then, the extract of cowslip is mixed with oil at a ratio of 10:1 to 1:1, and heated and stirred at a temperature of 30 to 70 DEG C until the water phase and the oil phase are mixed into a uniform emulsion, and the emulsion is cooled to room temperature to obtain the Pickering emulsion. The raw material of the extract of cowslip is raw cowslip or fried cowslip. When the raw material of the extract of cowslip is raw cowslip, the preparation method of the extract of cowslip is as follows: dried raw cowslip is soaked in deionized water at a ratio of 1:7, and then transferred to a pressurized extractor, and extracted at a pressure of 0.5 MPa and a temperature of 120 DEG C for 30 min, and then the extract is sprayed out through a sampling tube, filtered, and obtained as the extract of cowslip, which is stored in a 4 DEG C refrigerator for standby. When the raw material of the extract of cowslip is fried cowslip, the preparation method of the extract of cowslip is as follows: dried fried cowslip is soaked in deionized water at a ratio of 1:10 or 1:20, and then transferred to a pressurized extractor, and extracted at a pressure of 0.5 MPa or 1.0 MPa and a temperature of 120 DEG C, 130 DEG C or 140 DEG C for 10 min, 20 min or 30 min, and then the extract is sprayed out through a sampling tube, filtered, and obtained as the extract of cowslip, which is stored in a 4 DEG C refrigerator for standby.

2. The stachys-based Pickering emulsion according to claim 1, characterized in that, Only the extract of cowslip is used as the stabilizer, and no other auxiliary materials are needed in the preparation process.

3. The stachys-based Pickering emulsion according to claim 1, characterized in that, The extract of cowslip can be used to load fat-soluble ingredients. The extract of cowslip can be used to load fat-soluble ingredients.

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