Preparation and application of a Pickering multiple emulsion stabilized by phytosterol / chitosan composite particles

Abstract

The present invention discloses the preparation and application of a Pickering multiple emulsion stabilized by plant sterol / chitosan composite particles, comprising: mixing plant sterol particles with chitosan solution to obtain a plant sterol / chitosan composite particle dispersion; dissolving gelatin powder in deionized water, stirring the gelatin by magnetic force to fully dissolve the gelatin, and obtaining a gelatin solution; mixing the plant sterol / chitosan composite particle dispersion and the gelatin solution, adding them to an oil phase, and homogenizing at high speed to obtain a Pickering multiple emulsion. The Pickering multiple emulsion prepared by the present invention can be obtained by one-step homogenization, and the obtained emulsion outer phase has an obvious interface structure of particle adsorption; the multiple emulsion prepared by the unique particle stabilizer can emulsify different oil phases, and can meet the preparation requirements of various foods, cosmetics, and medicines.

Description

Technical Field

[0001] The invention belongs to the field of food cosmetics, and specifically relates to the preparation and application of a Pickering multiple emulsion stabilized by phytosterol / chitosan composite particles. Background Art

[0002] Multiple emulsions, also known as composite emulsions, are multi-layer emulsions formed by dispersing an emulsion in another continuous phase. Structurally, multiple emulsions have a unique multi-compartment structure of "two membranes and three phases", that is, water-in-oil-in-water or oil-in-water-in-oil emulsions, and their dispersed phase droplets contain smaller droplets of different phases. Due to the unique internal structure, multiple emulsions show great application potential in the fields of medicine, cosmetics, food and separation science.

[0003] However, conventional multiple emulsions are stabilized using surfactants with different hydrophile-lipophile balance values, and the presence of surfactants may cause toxicity problems to humans or other organisms in the environment. In addition, in terms of preparation methods, multiple emulsions are mostly prepared by a two-step process, that is, first, a primary emulsion is produced under high shear using an appropriate surfactant; then, other surfactants are added to the continuous phase while the mixture is slowly stirred. This multiple emulsion stabilized by surfactants is thermodynamically and kinetically unstable; and the second preparation process will to some extent destroy the structure of the emulsion obtained in the first step, resulting in poor stability of the multiple emulsion.

[0004] Pickering emulsion is an emulsion stabilized by colloidal particles. Compared with emulsions stabilized by surfactants, it has high stability, good biocompatibility, less foaming during the emulsification process and no pollution to the environment. These colloidal particles are irreversibly adsorbed at the oil-water interface, and the droplets are surrounded by tightly stacked particles, which reduces the total free energy of the system and effectively prevents the aggregation of droplets. At present, studies have used synthetic polymer particles and inorganic particles with unique amphiphilic properties to prepare Pickering multiple emulsions, which improve the stability of the emulsion while avoiding the use of surfactants. However, these particles have poor biocompatibility, are non-biodegradable, and are not environmentally friendly, which limits the application of the prepared multiple Pickering emulsions in the fields of cosmetics, food, and medicine. To this end, many studies have begun to focus on plant-based colloidal particles to develop Pickering multiple emulsions that can be used in the above fields.

[0005] Currently, there is no research on the preparation of safe, green and edible multiple Pickering emulsions using plant-derived colloidal particles in a one-step method.

[0006] Therefore, how to prepare a safe and edible Pickering multiple emulsion that is entirely plant-derived through a one-step method is a key issue that needs to be solved urgently. Summary of the invention

[0007] The purpose of this section is to summarize some aspects of embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the specification abstract and the invention title of this application to avoid blurring the purpose of this section, the specification abstract and the invention title, and such simplifications or omissions cannot be used to limit the scope of the present invention.

[0008] In view of the above problems and / or the problems existing in the prior art, the present invention is proposed.

[0009] Therefore, the purpose of the present invention is to overcome the deficiencies in the prior art and provide a method for preparing a Pickering multiple emulsion stabilized by phytosterol / chitosan composite particles.

[0010] In order to solve the above technical problems, the present invention provides the following technical solution: a method for preparing a Pickering multiple emulsion stabilized by phytosterol / chitosan composite particles, comprising:

[0011] mixing the phytosterol particles with the chitosan solution to obtain a phytosterol / chitosan composite particle dispersion;

[0012] Dissolve gelatin powder in deionized water, stir magnetically to fully dissolve the gelatin, and obtain a gelatin solution;

[0013] The phytosterol / chitosan composite particle dispersion and gelatin solution are mixed, added into the oil phase, and homogenized at high speed to obtain a Pickering multiple emulsion.

[0014] As a preferred embodiment of the preparation method of the present invention, the concentration of the phytosterol / chitosan composite particle dispersion is 0.5-2.5 wt %.

[0015] As a preferred embodiment of the preparation method of the present invention, the preparation method of the plant sterol particles comprises:

[0016] Dissolve the natural phytosterol powder in anhydrous ethanol and sonicate at 50°C for 10 minutes until completely dissolved;

[0017] Then, the obtained phytosterol ethanol solution was slowly added dropwise to water under mechanical stirring at 500 rpm. After 1 hour, the ethanol and part of the water were removed by rotary evaporation, and the mixture was freeze-dried to obtain phytosterol particles.

[0018] The phytosterols are derived from one or more of corn, soybean, white lotus seeds, watermelon seeds, almonds, pumpkin seeds, cashews, peanuts, hazelnuts, torreya grandis nuts, walnuts, pine nuts, sunflower seeds, and black sesame.

[0019] As a preferred embodiment of the preparation method of the present invention, the concentration of the gelatin solution is 0.5-5wt%.

[0020] As a preferred embodiment of the preparation method of the present invention, the volume ratio of the phytosterol / chitosan composite particle dispersion to the gelatin solution is 1:1-3; the homogenization time is 2-10 minutes, and the homogenization speed is 10000-25000 rpm.

[0021] As a preferred embodiment of the preparation method of the present invention, the oil phase comprises one or more of liquid paraffin, dodecane, hexadecane, diethyl carbonate, isopropyl myristate, triethylhexanoin, caprylic / capric triglyceride, isododecane, isohexadecane, polydimethylsiloxane, decamethylcyclopentasiloxane D5, squalane, hydrogenated polydecene, isononyl isononanoate, sunflower seed oil, olive oil, peanut oil, corn oil, soybean oil, camellia oil, and palm oil.

[0022] As a preferred embodiment of the preparation method of the present invention, the oil-water ratio is 1:1 to 7:3.

[0023] As a preferred embodiment of the preparation method of the present invention, the preparation method further comprises:

[0024] Active ingredients are added to the oil phase and the water phase to prepare Pickering multiple emulsions that simultaneously encapsulate both oil-soluble and water-soluble active ingredients.

[0025] As a preferred embodiment of the preparation method of the present invention, the oil-soluble active ingredients include β-carotene, lycopene, resveratrol, curcumin, quercetin, tocopherol, cinnamaldehyde, eugenol, limonene, linalool, rutin, naringin, retinol, and coenzyme Q-10; the water-soluble active ingredients include epigallocatechin gallate EGCG, vitamin C, proanthocyanidins, niacinamide, betaine, capsaicin, and caffeine.

[0026] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a method for preparing a Pickering multiple emulsion stabilized by plant sterol / chitosan composite particles, and the application of the obtained Pickering multiple emulsion in the fields of food, cosmetics and medicine.

[0027] Beneficial effects of the present invention:

[0028] (1) The Pickering multiple emulsion prepared by the present invention can be obtained by one-step homogenization, and the obtained emulsion external phase has an obvious interface structure of particle adsorption; the multiple emulsion prepared by the unique particle stabilizer can emulsify different oil phases and can meet the preparation requirements of various foods, cosmetics and medicines.

[0029] (2) The multi-Pickering emulsion prepared by the present invention has the characteristics of good biocompatibility of the particle stabilizer, biodegradability, renewability, small dosage, low cost and can be prepared by a one-step method.

[0030] (3) The Pickering multiple emulsion of the present invention has a good loading and protection effect on active substances and shows good application prospects in the fields of food, cosmetics and medicine. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor. Among them:

[0032] Figure 1 It is a microscope image of the Pickering multiple emulsion prepared in Comparative Examples 1-2 and Examples 1-4.

[0033] Figure 2 These are confocal microscopy images of the Pickering multiple emulsions prepared in Comparative Example 3 and Example 5.

[0034] Figure 3 It is the confocal microscopy image of Pickering multiple emulsion prepared in Comparative Example 4 and Examples 6-7.

[0035] Figure 4 These are the microscope images and appearance images of the Pickering multiple emulsions prepared in Examples 9-10.

[0036] Figure 5 These are the microscope images and appearance images of the Pickering multiple emulsions prepared in Examples 11-14.

[0037] Figure 6 The figure is a diagram showing the protective effect of the embedded active ingredients in Comparative Example 5, Comparative Example 6 and Examples 15-17 when stored at room temperature for 30 days.

[0038] Figure 7 The figure is a diagram showing the protective effect of Comparative Example 5, Comparative Example 6 and Examples 15-17 on the embedded active ingredients after UV radiation for 24 hours. DETAILED DESCRIPTION

[0039] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the embodiments of the specification.

[0040] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0041] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0042] The one-step method for preparing Pickering multiple emulsion of the present invention:

[0043] (1) Preparation of phytosterol particles: natural phytosterol powder was dissolved in anhydrous ethanol and ultrasonicated at 50° C. for 10 minutes until completely dissolved;

[0044] Then, under mechanical stirring at 500 rpm, the plant sterol ethanol solution obtained above was slowly added dropwise into water (the volume ratio of the plant sterol ethanol solution to water was 1:10);

[0045] After one hour, the ethanol and part of the water were removed by rotary evaporation, and the phytosterol particles were collected by freeze drying (freezing at -48°C for one week).

[0046] (2) Preparation of phytosterol / chitosan composite particle dispersion: Weigh an appropriate amount of chitosan powder and place it in an acetic acid solution (1 vol%), and stir it with a magnetic stirrer overnight to prepare a chitosan solution (pH 4.2);

[0047] Then, the freeze-dried phytosterol particles were dispersed in a chitosan solution of the same concentration, and magnetic stirring was performed for 10 minutes to ensure that they were fully mixed, thereby obtaining a phytosterol / chitosan composite particle dispersion.

[0048] (3) Preparation of gelatin solution: Weigh gelatin powder into deionized water and stir it with a magnetic stirrer at room temperature for 3 hours to allow it to fully swell; then stir it with a magnetic stirrer at 60° C. for 1 hour to allow the gelatin to fully dissolve, thereby obtaining a gelatin solution.

[0049] (4) Pickering multiple emulsion stability test:

[0050] The phytosterol / chitosan composite particle dispersion obtained in the above step is mixed with the gelatin solution, and the oil phase is immediately added and homogenized to obtain an oil-in-water-in-oil (o / w / o) Pickering multiple emulsion stabilized by the phytosterol / chitosan composite particles;

[0051] The prepared Pickering multiple emulsions were placed at different temperatures (4, 25, 37°C), and their appearances were regularly observed and optical microscope pictures were taken.

[0052] Application of Pickering Multi-Emulsion - Active Ingredient Protection:

[0053] Firstly, the oil-soluble active substance and the water-soluble active substance are dissolved in the oil phase and the water phase respectively to obtain the oil phase and the water phase containing the active substance;

[0054] The phytosterol / chitosan composite particle dispersion and gelatin solution were mixed with the oil phase and then homogenized to prepare a Pickering multiple emulsion containing the active ingredient;

[0055] The emulsion containing the active substance is placed at room temperature and UV irradiation conditions, and samples are taken from the emulsion regularly, wherein under room temperature conditions, samples are taken once at 0, 5, 10, 15, 20 and 30 days, respectively, and under UV irradiation conditions, samples are taken once at 0, 2, 4, 6, 8, 10 and 24 hours, respectively;

[0056] The outer oil phase was removed by low-temperature centrifugation at 4°C, and anhydrous ethanol, deionized water and n-hexane were added in sequence;

[0057] After vortexing, take the upper n-hexane phase and use UV-visible spectrophotometer to measure the content of oil-soluble active substances; take an appropriate amount of emulsion and add n-hexane to break the emulsion, and then add an appropriate amount of ultrapure water to dilute;

[0058] After centrifugation at 5000 rpm, the supernatant was taken and filtered through a 0.22 μm water filter membrane, and the content of water-soluble active ingredients was determined by high performance liquid chromatography.

[0059] Embodiment 1:

[0060] mixing the phytosterol / chitosan composite particle dispersion with the gelatin solution;

[0061] The concentration of the phytosterol / chitosan composite particles is 1wt%, the concentration of gelatin is 0.5wt%, and the volume ratio of the phytosterol / chitosan composite particle dispersion to the gelatin solution is 1:1;

[0062] The above solution was then mixed with D5, where the oil-water ratio was 1:1;

[0063] The o / w / o Pickering multiple emulsion was prepared by homogenization at 16000 rpm for 3 minutes.

[0064] Embodiment 2:

[0065] The phytosterol / chitosan composite particle dispersion is mixed with the gelatin solution, wherein the concentration of the phytosterol / chitosan composite particles is 1wt%, the concentration of the gelatin is 1wt%, and the volume ratio of the phytosterol / chitosan composite particle dispersion to the gelatin solution is 1:1.

[0066] The above solution was then mixed with D5 with an oil-water ratio of 1:1.

[0067] The o / w / o Pickering multiple emulsion was prepared by homogenization at 16000 rpm for 3 minutes.

[0068] Embodiment 3:

[0069] The phytosterol / chitosan composite particle dispersion was mixed with the gelatin solution. The concentration of the phytosterol / chitosan composite particles was 1wt%, the concentration of gelatin was 1.5wt%, and the volume ratio of the phytosterol / chitosan composite particle dispersion to the gelatin solution was 1:1. The above solution was then mixed with D5, wherein the oil-water ratio was 1:1. The o / w / o Pickering multiple emulsion was prepared by homogenizing at 16000rpm for 3 minutes.

[0070] Embodiment 4:

[0071] The phytosterol / chitosan composite particle dispersion was mixed with the gelatin solution. The concentration of the phytosterol / chitosan composite particles was 1wt%, the concentration of gelatin was 2.5wt%, and the volume ratio of the phytosterol / chitosan composite particle dispersion to the gelatin solution was 1:1. The above solution was then mixed with D5, wherein the oil-water ratio was 1:1. The o / w / o Pickering multiple emulsion was prepared by homogenizing at 16000rpm for 3 minutes.

[0072] Embodiment 5:

[0073] The phytosterol / chitosan composite particle dispersion was mixed with the gelatin solution. The concentration of the phytosterol / chitosan composite particles was 1wt%, the concentration of gelatin was 2.5wt%, and the volume ratio of the phytosterol / chitosan composite particle dispersion to the gelatin solution was 1:1. The above solution was then mixed with D5, wherein the oil-water ratio was 7:3. The o / w / o Pickering multiple emulsion was prepared by homogenizing at 16000rpm for 3 minutes.

[0074] Embodiment 6:

[0075] The phytosterol / chitosan composite particle dispersion was mixed with the gelatin solution. The concentration of the phytosterol / chitosan composite particles was 1 wt %, the concentration of gelatin was 2.5 wt %, and the volume ratio of the phytosterol / chitosan composite particle dispersion to the gelatin solution was 1:1. The above solution was then mixed with D5, wherein the oil-water ratio was 1:1. The o / w / o Pickering multiple emulsion was prepared by homogenizing at 16,000 rpm for 2 minutes.

[0076] Embodiment 7:

[0077] The phytosterol / chitosan composite particle dispersion was mixed with the gelatin solution. The concentration of the phytosterol / chitosan composite particles was 1wt%, the concentration of gelatin was 2.5wt%, and the volume ratio of the phytosterol / chitosan composite particle dispersion to the gelatin solution was 1:1. The above solution was then mixed with D5, wherein the oil-water ratio was 1:1. The o / w / o Pickering multiple emulsion was prepared by homogenizing at 16000rpm for 4 minutes.

[0078] Embodiment 8:

[0079] The phytosterol / chitosan composite particle dispersion was mixed with the gelatin solution. The concentration of the phytosterol / chitosan composite particles was 1wt%, the concentration of gelatin was 2.5wt%, and the volume ratio of the phytosterol / chitosan composite particle dispersion to the gelatin solution was 1:1. The above solution was then mixed with D5, wherein the oil-water ratio was 1:1. The o / w / o Pickering multiple emulsion was prepared by homogenizing at 16000rpm for 10 minutes.

[0080] Embodiment 9:

[0081] The phytosterol / chitosan composite particle dispersion was mixed with a gelatin solution. The concentration of the phytosterol / chitosan composite particles was 1 wt %, the concentration of gelatin was 2.5 wt %, and the volume ratio of the phytosterol / chitosan composite particle dispersion to the gelatin solution was 1:1. The above solution was then mixed with dodecane, wherein the oil-water ratio was 1:1. The o / w / o Pickering multiple emulsion was prepared by homogenizing at 16,000 rpm for 3 minutes.

[0082] Embodiment 10:

[0083] The phytosterol / chitosan composite particle dispersion was mixed with a gelatin solution. The concentration of the phytosterol / chitosan composite particles was 1 wt %, the concentration of gelatin was 2.5 wt %, and the volume ratio of the phytosterol / chitosan composite particle dispersion to the gelatin solution was 1:1. The above solution was then mixed with peanut oil, wherein the oil-water ratio was 1:1. The o / w / o Pickering multiple emulsion was prepared by homogenizing at 16,000 rpm for 3 minutes.

[0084] Embodiment 11:

[0085] The phytosterol / chitosan composite particle dispersion was mixed with the gelatin solution. The concentration of the phytosterol / chitosan composite particles was 0.5wt%, the concentration of gelatin was 2.5wt%, and the volume ratio of the phytosterol / chitosan composite particle dispersion to the gelatin solution was 1:1. The above solution was then mixed with D5, wherein the oil-water ratio was 1:1. The o / w / o Pickering multiple emulsion was prepared by homogenizing at 16000rpm for 3 minutes.

[0086] Embodiment 12:

[0087] The phytosterol / chitosan composite particle dispersion was mixed with the gelatin solution. The concentration of the phytosterol / chitosan composite particles was 0.75 wt %, the concentration of gelatin was 2.5 wt %, and the volume ratio of the phytosterol / chitosan composite particle dispersion to the gelatin solution was 1:1. The above solution was then mixed with D5, wherein the oil-water ratio was 1:1. The o / w / o Pickering multiple emulsion was prepared by homogenizing at 16000 rpm for 3 minutes.

[0088] Embodiment 13:

[0089] The phytosterol / chitosan composite particle dispersion was mixed with the gelatin solution. The concentration of the phytosterol / chitosan composite particles was 1.25wt%, the concentration of gelatin was 2.5wt%, and the volume ratio of the phytosterol / chitosan composite particle dispersion to the gelatin solution was 1:1. The above solution was then mixed with D5, wherein the oil-water ratio was 1:1. The o / w / o Pickering multiple emulsion was prepared by homogenizing at 16000rpm for 3 minutes.

[0090] Embodiment 14:

[0091] The phytosterol / chitosan composite particle dispersion was mixed with the gelatin solution. The concentration of the phytosterol / chitosan composite particles was 1.5wt%, the concentration of gelatin was 2.5wt%, and the volume ratio of the phytosterol / chitosan composite particle dispersion to the gelatin solution was 1:1. The above solution was then mixed with D5, wherein the oil-water ratio was 1:1. The o / w / o Pickering multiple emulsion was prepared by homogenizing at 16000rpm for 3 minutes.

[0092] Comparative Example 1:

[0093] mixing the phytosterol / chitosan composite particle dispersion with the gelatin solution;

[0094] The concentration of the phytosterol / chitosan composite particles is 1 wt %, the concentration of gelatin is 0.25 wt %, and the volume ratio of the phytosterol / chitosan composite particle dispersion to the gelatin solution is 1:1.

[0095] The above solution was then mixed with D5 with an oil-water ratio of 1:1.

[0096] The emulsion was prepared by homogenization at 16000 rpm for 3 minutes.

[0097] The emulsion obtained above was photographed under a microscope and it was found that the emulsion was not a multiple emulsion.

[0098] Comparative Example 2:

[0099] mixing the phytosterol / chitosan composite particle dispersion with the gelatin solution;

[0100] The concentration of the phytosterol / chitosan composite particles is 1 wt %, the concentration of gelatin is 0.05 wt %, and the volume ratio of the phytosterol / chitosan composite particle dispersion to the gelatin solution is 1:1.

[0101] The above solution was then mixed with D5 with an oil-water ratio of 1:1.

[0102] The emulsion was prepared by homogenization at 16000 rpm for 3 minutes.

[0103] The emulsion obtained above was photographed under a microscope and it was found that the emulsion was not a multiple emulsion.

[0104] Comparative Example 3:

[0105] mixing the phytosterol / chitosan composite particle dispersion with the gelatin solution;

[0106] The concentration of the phytosterol / chitosan composite particles is 1 wt %, the concentration of gelatin is 2.5 wt %, and the volume ratio of the phytosterol / chitosan composite particle dispersion to the gelatin solution is 1:1.

[0107] The above solution was then mixed with D5 with an oil-water ratio of 1:3.

[0108] The emulsion was prepared by homogenization at 16000 rpm for 3 minutes.

[0109] The emulsion obtained above was photographed under a microscope and it was found that the emulsion was not a multiple emulsion.

[0110] Comparative Example 4:

[0111] mixing the phytosterol / chitosan composite particle dispersion with the gelatin solution;

[0112] The concentration of the phytosterol / chitosan composite particles is 1 wt %, the concentration of gelatin is 2.5 wt %, and the volume ratio of the phytosterol / chitosan composite particle dispersion to the gelatin solution is 1:1.

[0113] The above solution was then mixed with D5 with an oil-water ratio of 1:1.

[0114] The emulsion was prepared by homogenization at 16000 rpm for 1 minute.

[0115] The emulsion obtained above was photographed under a microscope and it was found that the emulsion was not a multiple emulsion.

[0116] In summary, if Figure 1 As shown, the Pickering emulsion prepared by homogenizing solid particles of natural origin in one step in the present invention has the morphology of multiple emulsions. However, it is also found that as the concentration of aqueous gelatin decreases, the emulsion gradually changes from the multiple emulsion morphology to the Pickering oil-in-water emulsion, proving that the concentration of aqueous gelatin is crucial to the preparation of multiple emulsions.

[0117] Figure 2 The emulsion pictures of Comparative Example 3 and Example 5 show that the emulsion of Comparative Example 3 is a typical oil-in-water emulsion, which means that a stable Pickering multiple emulsion can be obtained only when the volume fraction of the oil phase reaches a certain level.

[0118] Figure 3 The emulsion pictures of Comparative Example 4 and Examples 6-7 show that Comparative Example 4 is also a typical oil-in-water emulsion, indicating that a stable Pickering multiple emulsion can be obtained only after sufficient homogenization time.

[0119] Figure 4 The emulsion pictures of Examples 9-10 show that the phytosterol / chitosan composite particles can emulsify different oil phases and prepare stable oil-in-water-in-oil Pickering multiple emulsions.

[0120] Figure 5 The emulsion images of Examples 11-14 show that when the concentration of the phytosterol / chitosan composite particles is as low as 0.5 wt%, the Pickering multiple emulsion can also be prepared, and as the concentration of the composite particles increases, the particle size of the Pickering multiple emulsion gradually decreases. This is because as the concentration of the composite particles increases, more particles can stabilize a larger oil-water interface, thereby obtaining a smaller oil droplet size.

[0121] Embodiment 15:

[0122] Epigallocatechin gallate (EGCG) was added into the phytosterol / chitosan composite particle dispersion and then mixed with the gelatin solution.

[0123] Among them, the concentration of phytosterol / chitosan composite particles is 1wt%, the concentration of gelatin is 2.5wt%, the volume ratio of phytosterol / chitosan composite particle dispersion to gelatin solution is 1:1, and the concentration of epigallocatechin gallate (EGCG) is 2mg / mg.

[0124] The above solution was then mixed with D5 containing β-carotene (β-C), wherein the oil-water ratio was 1:1 and the concentration of β-carotene was 0.2 mg / mL.

[0125] The Pickering multiple emulsion containing the active ingredient was prepared by homogenizing at 16000 rpm for 3 minutes.

[0126] Embodiment 16:

[0127] Epigallocatechin gallate (EGCG) was added to the phytosterol / chitosan composite particle dispersion and then mixed with the gelatin solution;

[0128] Among them, the concentration of phytosterol / chitosan composite particles is 1wt%, the concentration of gelatin is 2.5wt%, the volume ratio of phytosterol / chitosan composite particle dispersion to gelatin solution is 1:1, and the concentration of epigallocatechin gallate (EGCG) is 2mg / mg.

[0129] The above solution was then mixed with D5 with an oil-water ratio of 1:1.

[0130] The Pickering multiple emulsion containing the active ingredient was prepared by homogenizing at 16000 rpm for 3 minutes.

[0131] Embodiment 17:

[0132] mixing the phytosterol / chitosan composite particle dispersion with the gelatin solution;

[0133] The concentration of the phytosterol / chitosan composite particles is 1 wt %, the concentration of gelatin is 2.5 wt %, and the volume ratio of the phytosterol / chitosan composite particle dispersion to the gelatin solution is 1:1.

[0134] The above solution was then mixed with D5 containing β-carotene (β-C), wherein the oil-water ratio was 1:1 and the concentration of β-carotene was 0.2 mg / mL.

[0135] The Pickering multiple emulsion containing the active ingredient was prepared by homogenizing at 16000 rpm for 3 minutes.

[0136] Comparative Example 5:

[0137] Epigallocatechin gallate (EGCG) was dissolved in water to prepare an EGCG aqueous solution.

[0138] Comparative Example 6:

[0139] Epi-β-carotene (β-C) was dissolved in D5 to prepare a D5 oil phase containing β-C, and the concentration of β-carotene was 0.2 mg / mL.

[0140] like Figure 6 The results showed that after storage at room temperature for 30 days, the EGCG content in the Pickering multiple emulsion containing both EGCG and β-C decreased to 87.22% of the original content, and the β-C content decreased to 84.29% of the original content.

[0141] The content of EGCG in the Pickering multiple emulsion containing only EGCG was reduced to 76.25% of the original content, and the content of β-C in the Pickering multiple emulsion containing only β-C was reduced to 73.88% of the original content.

[0142] In comparative example 5, the content of EGCG was reduced to 11.18% of the original content, and in comparative example 6, the content of β-C was reduced to 25.36% of the original content. These data show that Pickering multiple emulsions can not only simultaneously encapsulate oil-soluble active substances and water-soluble active substances, but also effectively delay the degradation of the two types of active substances. At the same time, the Pickering multiple emulsions that co-encapsulate oil-soluble active substances and water-soluble active substances have a better protective effect on the corresponding active substances than the Pickering multiple emulsions that only encapsulate one active substance, which may be related to the synergistic antioxidant effect of β-C and EGCG.

[0143] like Figure 7The results showed that after storage for 1 hour under UV conditions, the EGCG content in the Pickering multiple emulsion containing both EGCG and β-C decreased to 75.50% of the original content, and the β-C content decreased to 79.57% of the original content. The EGCG content in the Pickering multiple emulsion containing only EGCG decreased to 70.90% of the original content, and the β-C content in the Pickering multiple emulsion containing only β-C decreased to 71.86% of the original content.

[0144] In comparative example 5, the content of EGCG was reduced to 58.37% of the original content, and in comparative example 6, the content of β-C was reduced to 27.85% of the original content. These data show that Pickering multiple emulsions can not only simultaneously encapsulate oil-soluble active substances and water-soluble active substances, but also effectively delay the degradation of the two types of active substances under UV radiation. At the same time, the Pickering multiple emulsions that co-encapsulate oil-soluble active substances and water-soluble active substances have a better protective effect on the corresponding active substances than the Pickering multiple emulsions that only encapsulate one active substance, which may be related to the synergistic antioxidant effect of β-C and EGCG.

[0145] The Pickering multiple emulsion prepared by the present invention has a simple preparation method, can be prepared by a one-step method, and the raw material source is natural and green, safe and non-toxic, and the oil phase used is edible vegetable oil, which is environmentally friendly. The present invention can prepare an edible Pickering emulsion multiple emulsion structure at a lower particle concentration, which is unprecedented. Moreover, the prepared Pickering multiple emulsion has a good loading and protection effect on oil-soluble and water-soluble active substances, laying a foundation for its application in the fields of food, medicine and cosmetics.

[0146] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the present invention.

Claims

1. A method for preparing a Pickering multiple emulsion stabilized by phytosterol / chitosan composite particles, characterized in that: include, The phytosterol particles are mixed with a chitosan solution to obtain a phytosterol / chitosan composite particle dispersion, wherein the concentration of the phytosterol / chitosan composite particle dispersion is 0.5-2.5 wt %; Dissolving gelatin powder in deionized water, stirring with magnetic force to fully dissolve the gelatin, and obtaining a gelatin solution, wherein the concentration of the gelatin solution is 0.5-5 wt%; The phytosterol / chitosan composite particle dispersion and gelatin solution are mixed, and the mixture is added into the oil phase as the aqueous phase, and homogenized at high speed to obtain a Pickering multiple emulsion, wherein the volume ratio of the phytosterol / chitosan composite particle dispersion and the gelatin solution is 1:1-3, the homogenization time is 2-10 minutes, the homogenization speed is 10000-25000 rpm, and the ratio of the oil phase to the water phase is 1:1-7:

3.

2. The preparation method according to claim 1, characterized in that: The preparation method of the plant sterol particles comprises: Dissolve the natural phytosterol powder in anhydrous ethanol and sonicate at 50°C for 10 minutes until completely dissolved; Then, the obtained phytosterol ethanol solution was slowly added dropwise to water under mechanical stirring at 500 rpm. After 1 hour, the ethanol and part of the water were removed by rotary evaporation, and the phytosterol particles were collected by freeze drying. The phytosterols are derived from one or more of corn, soybean, white lotus seeds, watermelon seeds, almonds, pumpkin seeds, cashews, peanuts, hazelnuts, torreya grandis nuts, walnuts, pine nuts, sunflower seeds, and black sesame.

3. The preparation method according to claim 1, characterized in that: The oil phase includes one or more of liquid paraffin, dodecane, hexadecane, isopropyl myristate, triethylhexanoin, caprylic / capric triglyceride, isododecane, isohexadecane, polydimethylsiloxane, decamethylcyclopentasiloxane D5, squalane, hydrogenated polydecene, isononyl isononanoate, sunflower seed oil, olive oil, peanut oil, corn oil, soybean oil, camellia oil, and palm oil.

4. The preparation method according to any one of claims 1 to 3, characterized in that: The preparation method further comprises: Active ingredients are added to the oil phase and the water phase to prepare Pickering multiple emulsions that simultaneously encapsulate both oil-soluble and water-soluble active ingredients.

5. The preparation method according to claim 4, characterized in that: The oil-soluble active ingredients include beta-carotene, lycopene, resveratrol, curcumin, quercetin, tocopherol, cinnamaldehyde, eugenol, limonene, linalool, rutin, naringin, retinol, and coenzyme Q-10; the water-soluble active ingredients include epigallocatechin gallate EGCG, vitamin C, proanthocyanidins, nicotinamide, betaine, capsaicin, and caffeine.

6. Use of the Pickering multiple emulsion prepared by the preparation method described in claim 1 or 2 in preparing food.

7. Use of the Pickering multiple emulsion prepared by the preparation method according to any one of claims 1 to 5 in the preparation of cosmetics and medicines.

Images