阅读说明：本技术 一种tpp线粒体靶向虾青素乳液及其制备方法 (TPP mitochondrion targeted astaxanthin emulsion and preparation method thereof ) 是由 谭明乾 张雪迪 铁珊珊 李佳璇 崔国馨 于 2019-10-15 设计创作，主要内容包括：本发明公开了一种TPP线粒体靶向虾青素乳液,包括组分：酪蛋白0.5～1mg/mL,中链甘油三酯0.1～0.2mL/mL,二甲基亚砜0.02～0.04mL/mL,三苯基溴化磷0.025～0.05mg/mL,1-(3-二甲氨基丙基)-3-乙基碳二亚胺盐酸盐0.025～0.05mg/mL,N-羟基琥珀酰亚胺0.01～0.025mg/mL,虾青素0.05～0.1mg/mL,余量为水；所述乳液的制备中,使用酪蛋白对虾青素进行包埋,并对乳液表面进行三苯基溴化磷修饰,所得乳液能靶向分布于线粒体；本发明实现了对营养素包埋的同时,使其靶向定位,发挥生物活性,避免外界环境对其生物活性的干扰破坏。(The invention discloses a TPP mitochondrion targeted astaxanthin emulsion, which comprises the following components: 0.5-1 mg/mL casein, 0.1-0.2 mL/mL medium chain triglyceride, 0.02-0.04 mL/mL dimethyl sulfoxide, 0.025-0.05 mg/mL triphenyl phosphonium bromide, 0.025-0.05 mg/mL 1- (3-dimethylaminopropyl) -3-ethyl carbodiimide hydrochloride, 0.01-0.025 mg/mL N-hydroxysuccinimide, 0.05-0.1 mg/mL astaxanthin and the balance of water; during the preparation of the emulsion, casein is used for embedding astaxanthin, triphenyl phosphonium bromide modification is carried out on the surface of the emulsion, and the obtained emulsion can be distributed on mitochondria in a targeted manner; the invention realizes the embedding of the nutrient, simultaneously leads the nutrient to be targeted and positioned, exerts the bioactivity and avoids the interference and damage of the external environment to the bioactivity.)

1. The TPP mitochondrion targeted astaxanthin emulsion is characterized by comprising the following components: 0.5-1 mg/mL casein, 0.1-0.2 mL/mL medium chain triglyceride, 0.02-0.04 mL/mL dimethyl sulfoxide, 0.025-0.05 mg/mL triphenyl phosphonium bromide, 0.025-0.05 mg/mL 1- (3-dimethylaminopropyl) -3-ethyl carbodiimide hydrochloride, 0.01-0.025 mg/mL N-hydroxysuccinimide, 0.05-0.1 mg/mL astaxanthin and the balance of water.

2. The TPP mitochondrially targeted astaxanthin emulsion according to claim 1, comprising the components: casein 1 mg/ml; medium chain triglycerides 0.1 ml/ml; dimethyl sulfoxide 0.04 ml/ml; 0.025mg/ml of triphenyl phosphonium bromide; 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride 0.025 mg/ml; 0.015mg/ml of N-hydroxysuccinimide; astaxanthin 0.05mg/ml, and water in balance.

3. A method of preparing the TPP mitochondrially targeted astaxanthin emulsion of claim 1, comprising the steps of:

s1, preparing casein emulsion: dissolving casein in deionized water to make the final concentration of the casein be 0.5 mg/mL-1 mg/mL to obtain a casein water solution; adding medium-chain triglyceride into casein water solution, and stirring and mixing uniformly to obtain mixed solution; carrying out ultrasonic crushing on the mixed solution, wherein the ultrasonic frequency is 600-800W, the ultrasonic time is 7-15 min, and the temperature is 20-30 ℃, so as to obtain casein emulsion; wherein the volume ratio of the casein aqueous solution to the medium chain triglyceride is 9: 1-4: 1;

s2, preparing a TPP carboxyl activating solution: the step is carried out at room temperature in a dark condition, and dimethyl sulfoxide is diluted into dimethyl sulfoxide solution with the volume fraction of 5% by deionized water; dissolving triphenyl phosphorus bromide and 1- (3-dimethylaminopropyl) -3-ethyl carbodiimide hydrochloride into a dimethyl sulfoxide solution with the volume fraction of 5%, stirring at 500-1000 rpm for 10-15 h, adding N-hydroxysuccinimide, and stirring at 500-1000 rpm for 4-6 h to obtain a TPP carboxyl activation solution;

wherein in the TPP carboxyl activating solution, the concentration of triphenyl phosphorus bromide is 2.5-5 mg/mL, the concentration of 1- (3-dimethylaminopropyl) -3-ethyl carbodiimide hydrochloride is 2.5-5 mg/mL, and the concentration of N-hydroxysuccinimide is 1-2.5 mg/mL;

s3, preparing astaxanthin-loaded casein emulsion: dissolving astaxanthin in medium-chain triglyceride to obtain MCT oil phase loaded with astaxanthin, wherein the concentration of the astaxanthin is 0.5-1 mg/mL; adding the MCT oil phase carrying the astaxanthin into the casein emulsion in the step S1, and uniformly stirring; carrying out ultrasonic crushing treatment, wherein the ultrasonic frequency is 600-800W, the ultrasonic time is 7-15 min, and the temperature is 20-30 ℃, so as to prepare the casein emulsion carrying the astaxanthin; wherein the volume ratio of the casein emulsion to the MCT oil phase loaded with astaxanthin is 9: 1-4: 1;

s4, preparing a TPP mitochondrion targeted astaxanthin emulsion: mixing the astaxanthin-loaded casein emulsion obtained in the step S3 with the TPP carboxyl activation liquid obtained in the step S2 according to the volume ratio of 100: 1-50: 1, and stirring at 500-1000 rpm for 2-5 hours to obtain a TPP mitochondrion targeted astaxanthin emulsion;

the TPP mitochondrion targeted astaxanthin emulsion comprises the following components: 0.5-1 mg/mL casein, 0.1-0.2 mL/mL medium chain triglyceride, 0.02-0.04 mL/mL dimethyl sulfoxide, 0.025-0.05 mg/mL triphenyl phosphonium bromide, 0.025-0.05 mg/mL 1- (3-dimethylaminopropyl) -3-ethyl carbodiimide hydrochloride, 0.01-0.025 mg/mL N-hydroxysuccinimide, 0.05-0.1 mg/mL astaxanthin and the balance of water.

4. The preparation method of the TPP mitochondrion targeted astaxanthin emulsion according to claim 3, wherein the stirring and uniformly mixing in the step S1 is 500-1000 rpm for 30-60 min.

5. The method of preparing an emulsion of TPP mitochondrion-targeted astaxanthin according to claim 3, wherein the aqueous casein solution prepared in step S1 is prepared by dissolving casein in deionized water, and stirring at 40 ℃ for 30min to obtain an aqueous casein solution having a final casein concentration of 0.5-1 mg/mL.

6. The preparation method of the TPP mitochondrion targeted astaxanthin emulsion according to claim 3, wherein the stirring and uniformly mixing in the step S3 is 500-1000 rpm for 15-30 min.

7. The method for preparing the TPP mitochondrially targeted astaxanthin emulsion according to claim 2, comprising the steps of:

s1, preparing casein emulsion: weighing casein, adding deionized water to make the concentration of the casein be 1mg/mL, and stirring in a water bath kettle at 40 ℃ for 30min to obtain a casein water solution; dropwise adding medium-chain triglyceride into the casein aqueous solution, fully stirring for 30min at 800rpm, and then carrying out ultrasonic crushing treatment, wherein the ultrasonic frequency is 700W, the ultrasonic time duration is 7min, and the temperature is 25 ℃, so as to prepare casein emulsion; wherein the volume ratio of the casein aqueous solution to the medium chain triglyceride is 9: 1;

s2, preparing a TPP carboxyl activating solution: the step is carried out under the condition of room temperature and light resistance; diluting dimethyl sulfoxide with deionized water to obtain a dimethyl sulfoxide solution with the volume fraction of 5%; dissolving triphenyl phosphorus bromide and 1- (3-dimethylaminopropyl) -3-ethyl carbodiimide hydrochloride in a dimethyl sulfoxide solution with the volume fraction of 5%, stirring at 800rpm for 15 hours, adding N-hydroxysuccinimide, and stirring at 800rpm for 5 hours to obtain a TPP carboxyl activation solution;

wherein the concentration of triphenyl phosphorus bromide in the TPP carboxyl activation solution is 2.5mg/mL, the concentration of 1- (3-dimethylaminopropyl) -3-ethyl carbodiimide hydrochloride is 2.5mg/mL, and the concentration of N-hydroxysuccinimide is 1.5 mg/mL;

s3, preparing astaxanthin-loaded casein emulsion: dissolving 0.5mg of astaxanthin in 1mL of medium chain triglyceride, wherein the concentration of the astaxanthin is 0.5mg/mL, and obtaining MCT oil phase loaded with the astaxanthin; adding the MCT oil phase loaded with the astaxanthin into the casein emulsion in the step S1 with the volume being 9 times that of the oil phase, and stirring the mixture at 800rpm for 30 min; carrying out ultrasonic crushing treatment, wherein the ultrasonic frequency is 700W, the ultrasonic time is 7min, and the temperature is 25 ℃, so as to prepare the casein emulsion carrying the astaxanthin;

s4, preparing a TPP mitochondrion targeted astaxanthin emulsion: mixing the astaxanthin-loaded casein emulsion obtained in the step S3 and the TPP carboxyl activation solution obtained in the step S2 according to the volume ratio of 100:1, and stirring at 600rpm for 3 hours to obtain a TPP mitochondrion targeted astaxanthin emulsion;

the TPP mitochondrion targeted astaxanthin emulsion comprises the following components: casein 1 mg/ml; medium chain triglycerides 0.1 ml/ml; dimethyl sulfoxide 0.04 ml/ml; 0.025mg/ml of triphenyl phosphonium bromide; 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride 0.025 mg/ml; 0.015mg/ml of N-hydroxysuccinimide; astaxanthin 0.05mg/ml, and water in balance.

Technical Field

The invention relates to the technical field of food and health food, in particular to TPP mitochondrion targeted astaxanthin emulsion and a preparation method thereof.

Background

Astaxanthin is a terpene-based unsaturated compound, one of the most common carotenoids, distributed in the feathers of shrimps, crabs, fish, fronds, yeasts, crustaceans and birds. Astaxanthin is mainly in the esterified state, but is mainly in the free state in muscles, blood plasma, and internal organs. The astaxanthin molecule contains long conjugated unsaturated double bond structure, so that the astaxanthin molecule has strong biological activity, including antioxidation, anti-lipid peroxidation activity, anti-inflammation, cardiovascular disease prevention, immunoregulation and the like. But the biological activity of the biological activity-losing agent is easily damaged by environmental factors such as light, heat, oxygen, pH and the like, and the biological utilization rate is low.

Functional factors (such as carotenoids, flavonoids, phytosterols, polyunsaturated fats, oil-soluble vitamins and the like) in food are easily influenced by external environments such as light, pH, temperature and the like to destroy the biological activity of the functional factors. Therefore, it is necessary to construct a delivery system capable of stabilizing the biological activity of the functional factor. The emulsion plays a key role as a delivery system of the functional factors, and realizes the protection, delivery and controlled release of the functional factors. Common emulsion types include traditional emulsions, Pickering emulsions, multiple emulsions, multi-layer emulsions, as well as emulsion-based solid lipid particles and hydrogel-filled particles, among others. Although the stability of the functional factors is improved by the emulsion constructed in the traditional way, the targeted positioning and releasing functions cannot be realized, so that the functional factors cannot be efficiently and intensively distributed on action sites, and the titer of the functional factors is reduced.

Disclosure of Invention

The invention aims to overcome the defects of the prior art, realizes the in-vitro targeted delivery effect of the astaxanthin emulsion through modification of triphenyl phosphorus bromide (TPP), promotes astaxanthin to fully enter cells to further exert the biological efficacy of the astaxanthin, and realizes the fixed-point and positioned release and controllable effect of bioactive substances.

In order to achieve the aim, the invention provides a TPP mitochondrion targeted astaxanthin emulsion, which comprises the following components: 0.5-1 mg/mL casein, 0.1-0.2 mL/mL MCT (medium chain triglyceride), 0.02-0.04 mL/mL DMSO (dimethyl sulfoxide), 0.025-0.05 mg/mL TPP (triphenyl phosphorus bromide), 0.025-0.05 mg/mL EDC (1- (3-dimethylaminopropyl) -3-ethyl carbodiimide hydrochloride), 0.01-0.025 mg/mL NHS (N-hydroxysuccinimide), 0.05-0.1 mg/mL astaxanthin and the balance of water.

Preferably, the TPP mitochondrially targeted astaxanthin emulsion comprises the following components: casein 1mg/mL, MCT (medium chain triglyceride) 0.1mL/mL, DMSO (dimethyl sulfoxide) 0.04mL/mL, TPP (triphenyl phosphonium bromide) 0.025mg/mL, EDC (1- (3-dimethylaminopropyl) -3-ethyl carbodiimide hydrochloride) 0.025mg/mL, NHS (N-hydroxysuccinimide) 0.015mg/mL, astaxanthin 0.05mg/mL, and the balance water.

A preparation method of TPP mitochondrion targeted astaxanthin emulsion comprises the following steps:

s1, preparing casein emulsion: weighing casein, dissolving the casein in deionized water to enable the final concentration of the casein to be 0.5 mg/mL-1 mg/mL, and obtaining a casein water solution; adding MCT (medium chain triglyceride) into casein water solution, and stirring and mixing to obtain mixed solution; carrying out ultrasonic crushing on the mixed solution, wherein the ultrasonic frequency is 600-800W, the ultrasonic time is 7-15 min, and the temperature is 20-30 ℃, so as to obtain casein emulsion; wherein the volume ratio of the casein aqueous solution to MCT is 9: 1-4: 1;

s2, preparing a TPP carboxyl activating solution: diluting DMSO (dimethyl sulfoxide) into a DMSO solution with the volume fraction of 5% by using deionized water; under the condition of room temperature and light shielding, TPP (triphenyl phosphorus bromide) and EDC (1- (3-dimethylaminopropyl) -3-ethyl carbodiimide hydrochloride) are fully dissolved in a DMSO solution with the volume fraction of 5%, stirred at 500-1000 rpm for 10-15 h, and then NHS (N-hydroxysuccinimide) is added and stirred at 500-1000 rpm for 4-6 h, so that TPP carboxyl activation liquid is obtained;

wherein, in the TPP carboxyl activating solution, the concentration of TPP (triphenyl phosphorus bromide) is 2.5-5 mg/mL, the concentration of EDC (1- (3-dimethylaminopropyl) -3-ethyl carbodiimide hydrochloride) is 2.5-5 mg/mL, and the concentration of NHS (N-hydroxysuccinimide) is 1-2.5 mg/mL;

s3, preparing astaxanthin-loaded casein emulsion: dissolving astaxanthin in MCT, wherein the concentration of the astaxanthin is (W/V) 0.5-1 mg/mL, and obtaining MCT oil phase loaded with astaxanthin; adding the MCT oil phase carrying the astaxanthin into the casein emulsion in the step S1, and uniformly stirring; carrying out ultrasonic crushing treatment, wherein the ultrasonic frequency is 600-800W, the ultrasonic time is 7-15 min, and the temperature is 20-30 ℃, so as to prepare the casein emulsion carrying the astaxanthin; wherein the volume ratio of the casein emulsion to the MCT oil phase loaded with astaxanthin is 9: 1-4: 1;

s4, preparing a TPP mitochondrion targeted astaxanthin emulsion: mixing the astaxanthin-loaded casein emulsion obtained in the step S3 with the TPP carboxyl activation liquid obtained in the step S2 according to the volume ratio of 100: 1-50: 1, and stirring at 500-1000 rpm for 2-5 hours to obtain a TPP mitochondrion targeted astaxanthin emulsion;

the TPP mitochondrion targeted astaxanthin emulsion comprises the following components: 0.5-1 mg/mL casein, 0.1-0.2 mL/mL medium chain triglyceride, 0.02-0.04 mL/mL dimethyl sulfoxide, 0.025-0.05 mg/mL triphenyl phosphonium bromide, 0.025-0.05 mg/mL 1- (3-dimethylaminopropyl) -3-ethyl carbodiimide hydrochloride, 0.01-0.025 mg/mL N-hydroxysuccinimide, 0.05-0.1 mg/mL astaxanthin and the balance of water.

In a preferable mode, the stirring and uniformly mixing in the step S1 is performed at 500-1000 rpm for 30-60 min; the preparation method of the casein water solution comprises the steps of dissolving casein in deionized water, stirring at 40 ℃ for 30min to dissolve the casein, and enabling the final concentration of the casein to be 0.5-1 mg/mL.

Preferably, the stirring and mixing in step S3 is performed at 500-1000 rpm for 15-30 min.

In a preferred mode, the preparation method of the TPP mitochondrion targeted astaxanthin emulsion comprises the following steps:

s1, preparing casein emulsion: weighing casein, dissolving in deionized water to make casein final concentration 1mg/mL, and dissolving in 40 deg.C water bath for 30min to obtain casein water solution; dropwise adding MCT (medium chain triglyceride) into the casein aqueous solution, fully stirring for 30min at 800rpm, and carrying out ultrasonic crushing treatment on the emulsion after full stirring, wherein the ultrasonic frequency is 700W, the ultrasonic time is 7min, and the temperature is 25 ℃, so as to obtain casein emulsion; wherein the volume ratio of the casein aqueous solution to MCT is 9: 1;

s2, preparing a TPP carboxyl activating solution: the step is carried out under the condition of room temperature and light resistance; diluting DMSO (dimethyl sulfoxide) into a DMSO solution with the volume fraction of 5% by using deionized water; TPP (triphenyl phosphorus bromide) and EDC (1- (3-dimethylaminopropyl) -3-ethyl carbodiimide hydrochloride) are fully dissolved in DMSO solution with the volume fraction of 5%, and are stirred and fully reacted for 15 hours under the condition of 800rpm, so that reaction liquid of TPP and EDC is obtained; adding NHS (N-hydroxysuccinimide) into the reaction liquid of the TPP and the EDC, and stirring and fully reacting for 5h under the condition of 800rpm to obtain TPP carboxyl activation liquid;

wherein the TPP carboxyl activating solution has TPP (triphenyl phosphorus bromide) concentration of 2.5mg/mL, EDC (1- (3-dimethylaminopropyl) -3-ethyl carbodiimide hydrochloride) concentration of 2.5mg/mL and NHS (N-hydroxysuccinimide) concentration of 1.5 mg/mL;

s3, preparing astaxanthin-loaded casein emulsion: dissolving 0.5mg of astaxanthin in 1mL of MCT, wherein the concentration of the astaxanthin is (W/V)0.5mg/mL, and obtaining an MCT oil phase carrying the astaxanthin; adding the MCT oil phase loaded with the astaxanthin into the casein emulsion in the step S1 with the volume 9 times that of the oil phase, and fully stirring the mixture for 30min at the condition of 800 rpm; carrying out ultrasonic crushing treatment, wherein the ultrasonic frequency is 700W, the ultrasonic time is 7min, and the temperature is 25 ℃, so as to prepare the casein emulsion carrying the astaxanthin;

s4, preparing a TPP mitochondrion targeted astaxanthin emulsion: and (3) mixing the astaxanthin-loaded casein emulsion obtained in the step S3 and the TPP carboxyl activation solution obtained in the step S2 according to the volume ratio of 100:1, and stirring for 3 hours at 600rpm to obtain the TPP mitochondrion targeted astaxanthin emulsion.

The invention has the beneficial effects that: the invention provides a preparation method of TPP mitochondrion targeted astaxanthin emulsion, which constructs an emulsion system with targeting property through the modification effect of TPP mitochondrion targeted molecules. The TPP mitochondrion targeted astaxanthin emulsion constructed by the invention has distribution targeting property and promotes the high-efficiency exertion of the biological activity of astaxanthin; TPP mitochondrion targeted astaxanthin emulsion can obviously reduce the active oxygen level in RAW264.7 cells; the TPP mitochondrion targeted astaxanthin emulsion has better promotion effect on the activity of RAW264.7 macrophage than astaxanthin.

Drawings

FIG. 1 is a dynamic light scattering diagram of the casein emulsion and TPP-modified casein emulsion in comparative example 1.

FIG. 2 is a laser confocal bright field diagram of the casein emulsion in comparative example 1.

FIG. 3 is a laser confocal bright field diagram of the TPP-modified casein emulsion in comparative example 1.

FIG. 4 is a cold field scanning electron micrograph (30.0K) of the casein emulsion of comparative example 1.

FIG. 5 is a cold field scanning electron micrograph (30.0K) of the TPP-modified casein emulsion of comparative example 1.

FIG. 6 is a graph showing a fluorescence distribution of the casein emulsion supporting astaxanthin in comparative example 2 in NRK cells.

FIG. 7 is a graph showing the fluorescence distribution of TPP mitochondrially targeted astaxanthin emulsion in NRK cells in comparative example 2.

Fig. 8 is a graph showing a fluorescence distribution of the casein emulsion supporting astaxanthin in comparative example 2 on RAW264.7 macrophage cells.

FIG. 9 is a graph showing the fluorescence distribution of TPP mitochondrially targeted astaxanthin emulsion in comparative example 2 on RAW264.7 macrophages.

Fig. 10 is a graph showing a fluorescence distribution of the astaxanthin-loaded casein emulsion of comparative example 2 at the mitochondria of RAW264.7 macrophage cells.

FIG. 11 is a graph showing the fluorescence distribution of TPP mitochondrially targeted astaxanthin emulsion in comparative example 2 at RAW264.7 macrophage mitochondrion.

FIG. 12 is a fluorescent inversion plot of reactive oxygen species generated by hydrogen peroxide treated RAW264.7 macrophages.

FIG. 13 is a fluorescence inversion diagram of the production of reactive oxygen species by RAW264.7 macrophages after hydrogen peroxide treatment in the casein emulsion supporting astaxanthin in example 1.

FIG. 14 is a fluorescent inversion plot of the TPP mitochondrially targeted astaxanthin emulsion in example 1 on the production of reactive oxygen species by RAW264.7 macrophages after hydrogen peroxide treatment.

FIG. 15 is a graph showing MTT results of three sample solutions of sample (A), sample (B) and sample (C) in example 1 on RAW264.7 macrophages.

Detailed Description

The present invention is further illustrated by the following specific examples.

A preparation method of TPP mitochondrion targeted astaxanthin emulsion comprises the following steps:

s1, preparing casein emulsion: weighing casein, dissolving the casein in deionized water to enable the final concentration of the casein to be 0.5 mg/mL-1 mg/mL, and obtaining a casein water solution; adding MCT (medium chain triglyceride) into the casein aqueous solution, and stirring at 500-1000 rpm for 15-30 min to obtain a mixed solution; carrying out ultrasonic crushing on the mixed solution, wherein the ultrasonic frequency is 600-800W, the ultrasonic time is 7-15 min, and the temperature is 20-30 ℃, so as to obtain casein emulsion; wherein the volume ratio of the casein aqueous solution to MCT is 9: 1-4: 1;

s2, preparing a TPP carboxyl activating solution: diluting DMSO (dimethyl sulfoxide) into a DMSO solution with the volume fraction of 5% by using deionized water; under the condition of room temperature and light shielding, TPP (triphenyl phosphorus bromide) and EDC (1- (3-dimethylaminopropyl) -3-ethyl carbodiimide hydrochloride) are fully dissolved in a DMSO solution with the volume fraction of 5%, stirred at 500-1000 rpm for 10-15 h, and then NHS (N-hydroxysuccinimide) is added and stirred at 500-1000 rpm for 4-6 h, so that TPP carboxyl activation liquid is obtained;

wherein, in the TPP carboxyl activating solution, the concentration of TPP (triphenyl phosphorus bromide) is 2.5-5 mg/mL, the concentration of EDC (1- (3-dimethylaminopropyl) -3-ethyl carbodiimide hydrochloride) is 2.5-5 mg/mL, and the concentration of NHS (N-hydroxysuccinimide) is 1-2.5 mg/mL;

s3, preparing astaxanthin-loaded casein emulsion: dissolving astaxanthin in MCT, wherein the concentration of the astaxanthin is (W/V) 0.5-1 mg/mL, and obtaining MCT oil phase loaded with astaxanthin; adding the MCT oil phase loaded with the astaxanthin into the casein emulsion in the step S1, and stirring at 500-1000 rpm for 15-30 min; carrying out ultrasonic crushing treatment, wherein the ultrasonic frequency is 600-800W, the ultrasonic time is 7-15 min, and the temperature is 20-30 ℃, so as to prepare the casein emulsion carrying the astaxanthin; wherein the volume ratio of the casein emulsion to the MCT oil phase loaded with astaxanthin is 9: 1-4: 1;

s4, preparing a TPP mitochondrion targeted astaxanthin emulsion: and (3) mixing the astaxanthin-loaded casein emulsion obtained in the step S3 and the TPP carboxyl activation liquid obtained in the step S2 according to the volume ratio of 100: 1-50: 1, and stirring at 500-1000 rpm for 2-5 hours to obtain the TPP mitochondrion targeted astaxanthin emulsion.

The TPP mitochondrion targeted astaxanthin emulsion is an (O/W) oil-in-water emulsion constructed by a W water phase, an O oil phase and TPP in a targeted manner. MCT (medium chain triglyceride) is used as the oil phase of the emulsion, casein and pure water are used as the water phase, and TPP (triphenyl phosphorus bromide) is used as a target substance to be covalently bonded with the casein.