Zeaxanthine nanoparticles as well as preparation method and application thereof

Abstract

The invention discloses zeaxanthin nano-particles and a preparation method and application thereof, and belongs to the technical field of food-based delivery systems.The zeaxanthin nano-particles are formed by coating zein on the surface of zeaxanthin, and the zeaxanthin nano-particles are formed by coating corn filament polysaccharide on the surface of the protein nano-particles; the mass ratio of the zeaxanthine to the zein to the corn filament polysaccharide is 0.01: (0.6-10): (0.6-10). According to the invention, the zein and the corn filament polysaccharide are sequentially wrapped on the outer layer of the zeaxanthine in a self-assembly manner to form a core-shell structure, so that the aim of protecting the zeaxanthine is fulfilled. The corn filament polysaccharide on the outermost layer of the prepared zeaxanthine nano-particles is water-soluble polysaccharide, the solubility of the nano-particles is improved while the zeaxanthine is protected, and the utilization rate of the zeaxanthine is further improved.

Description

Technical Field

[0001] This invention relates to the field of food-based delivery systems, specifically to a zeaxanthin nanoparticle, its preparation method, and its application. Background Technology

[0002] Zeaxanthin, also known as zeaxanthin, is an isomer of lutein and a natural derivative of carotenoids. It is widely found in plants such as corn, goji berries, and marigolds, as well as algae and photosynthetic bacteria. It is a natural fat-soluble pigment. Zeaxanthin has various effects, including antioxidant activity, regulation of glucose and lipid metabolism, and cancer prevention. However, its easy decomposition under light and heat conditions and poor water solubility severely limit its application in the food industry.

[0003] Currently, food-based delivery systems are mainly used to address the issues of zeaxanthin's easy decomposition under light and heat conditions and its poor water solubility. Food-based delivery systems are a series of carrier systems developed based on food-derived polysaccharides, proteins, and lipids, aiming to improve the stability and bioactivity of active substances in food, and to achieve functions such as protection, sustained release, and targeted delivery. Food-based delivery systems include delivery forms such as hydrogels, Pickering emulsions, microcapsules, and nanoparticles. Among them, nanoparticles are a core-shell structured delivery system that regulates the time and space of substance release in a sequentially controlled manner. For example, wheat gliadin / soy protein isolate nanoparticles are used to encapsulate astaxanthin. However, the commonly used wall materials for nanoparticles are generally polysaccharides such as sodium alginate, chitosan, and gum arabic, none of which possess bioactive functions, thus affecting the efficacy of zeaxanthin. Summary of the Invention

[0004] This invention provides zeaxanthin nanoparticles, their preparation method, and applications, effectively solving the technical problem that the wall materials commonly used in existing nanoparticles lack bioactivity. This invention utilizes self-assembly to encapsulate zeaxanthin with zein to form protein nanoparticles, and then uses corn silk polysaccharide to encapsulate the aforementioned protein nanoparticles, forming composite nanoparticles of corn silk polysaccharide-zein-zeaxanthin, thereby achieving the effect of protecting and efficiently utilizing zeaxanthin.

[0005] The first objective of this invention is to provide zeaxanthin nanoparticles, comprising a core material and a first wall material and a second wall material sequentially coated on the surface of the core material. The core material is zeaxanthin, the first wall material is zein, and the second wall material is corn silk polysaccharide. The mass ratio of zeaxanthin, zein and corn silk polysaccharide is 0.01:0.6-10:0.6-10.

[0006] In a preferred embodiment, the particle size of the zeaxanthin nanoparticles is 137 nm to 342 nm.

[0007] In a preferred embodiment, the encapsulation efficiency of the zeaxanthin nanoparticles is 75.42% to 92.33%.

[0008] A second objective of this invention is to provide a method for preparing the above-mentioned zeaxanthin nanoparticles, comprising the following steps: An ethanol solution of zeaxanthin was added to an ethanol solution of zein and stirred to mix. Water was added for the first time to evaporate and remove the ethanol. Water was added for the second time to adjust the pH to 4-5, so that zein coated the surface of zeaxanthin, resulting in a protein nanoparticle solution.

[0009] A corn silk polysaccharide aqueous solution with a pH of 4-5 was mixed with the protein nanoparticle solution. Through a self-assembly reaction, the corn silk polysaccharide was coated onto the surface of the protein nanoparticles to obtain zeaxanthin nanoparticles.

[0010] In a preferred embodiment, after stirring and mixing, a first mixture is obtained, wherein the volume ratio of the first mixture to the water added for the first time is 1:1.8 to 3; and a second mixture is obtained after the first addition of water.

[0011] In a preferred embodiment, the stirring is performed at a speed of 400 rpm to 600 rpm for 1 to 3 hours.

[0012] In a preferred embodiment, the mass ratio of zein to zein polysaccharide is 1:1.

[0013] In a preferred embodiment, the self-assembly reaction is as follows: a corn silk polysaccharide aqueous solution with a pH of 4-5 is mixed with the protein nanoparticle solution, and stirred at a speed of 400 rpm-600 rpm for 30 min-60 min to obtain zeaxanthin nanoparticles.

[0014] In a preferred embodiment, after the self-assembly reaction is completed, a mixed solution is obtained, which is centrifuged at 3000 rpm to 4000 rpm for 10 min to 15 min to remove the precipitate. The supernatant is then frozen at -40℃ to -30℃ for 14 h and then dried at -25℃ to -20℃ for 10 h to obtain zeaxanthin nanoparticles.

[0015] A third objective of this invention is to provide an application of the above-mentioned zeaxanthin nanoparticles in the preparation of drugs that regulate glucose and lipid metabolism.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention provides zeaxanthin nanoparticles. Zeaxanthin is coated with zein to form protein nanoparticles, and the protein nanoparticles are then coated with corn silk polysaccharide to form zeaxanthin nanoparticles. The mass ratio of zeaxanthin, zein, and corn silk polysaccharide is 0.01:0.6-10:0.6-10. This invention utilizes a self-assembly method to sequentially encapsulate zeaxanthin with zein and corn silk polysaccharide to form a core-shell structure, thereby achieving the purpose of protecting zeaxanthin. This invention first uses zein to encapsulate zeaxanthin to form a core-shell structure, and then uses corn silk polysaccharide to coat the zein nanoparticles for protection. The order of encapsulation with zein and corn silk polysaccharide cannot be changed; otherwise, the nanoparticle structure cannot be formed. Encapsulating zeaxanthin with zein facilitates the formation of a core-shell structure and is easy to encapsulate, but the stability and water solubility of the resulting core-shell structure are poor. Therefore, corn silk polysaccharide is needed as a protective agent to coat the outermost layer, thereby effectively improving the utilization rate of zeaxanthin.

[0017] The outermost layer of the zeaxanthin nanoparticles prepared in this invention, composed of water-soluble corn silk polysaccharides, protects zeaxanthin while increasing the solubility of the nanoparticles, thus further improving the utilization rate of zeaxanthin. The corn silk polysaccharides used in this invention's nanoparticle system exhibit superior bioactivity; they can act as prebiotics after release to lower blood sugar, and they can also bind to zeaxanthin to enhance its weight-loss and lipid-lowering effects. Compared to other types of polysaccharides, this invention provides a more suitable delivery medium for zeaxanthin through the preparation of nanoparticles using corn silk polysaccharides. Attached Figure Description

[0018] Figure 1 This is a comparison diagram of the particle size of zeaxanthin nanoparticles prepared in Examples 1 to 5 and Comparative Example 1 of the present invention.

[0019] Figure 2 This is a comparison diagram of the zeta potentials of the zeaxanthin nanoparticles prepared in Examples 1 to 5 and Comparative Example 1 of the present invention.

[0020] Figure 3 The diagram shows a comparison of the PDI of zeaxanthin nanoparticles prepared in Examples 1 to 5 and Comparative Example 1 of this invention.

[0021] Figure 4 This is a comparison chart of the encapsulation efficiency of zeaxanthin nanoparticles prepared in Examples 1 to 5 and Comparative Example 1 of the present invention.

[0022] exist Figures 1-4In the examples, ZZ represents the zeaxanthin nanoparticles obtained in Comparative Example 1, CZZ5:1 represents the zeaxanthin nanoparticles obtained in Example 1, CZZ3:1 represents the zeaxanthin nanoparticles obtained in Example 2, CZZ1:1 represents the zeaxanthin nanoparticles obtained in Example 3, CZZ1:3 represents the zeaxanthin nanoparticles obtained in Example 4, and CZZ1:5 represents the zeaxanthin nanoparticles obtained in Example 5.

[0023] Figure 5 The images shown are pathological sections of the livers of mice in this invention. Image A is a pathological section of the liver of mice in the blank control group, Image B is a pathological section of the liver of mice in the model group, Image C is a pathological section of the liver of mice in the positive control group, Image D is a pathological section of the liver of mice in the corn silk polysaccharide group, Image E is a pathological section of the liver of mice in the zeaxanthin group, and Image F is a pathological section of the liver of mice in the nanoflavin nanoparticle group of Example 3.

[0024] Figure 6 This is a comparison diagram of the particle size of zeaxanthin nanoparticles prepared in Example 3 and Comparative Examples 2 to 9 of the present invention.

[0025] Figure 7 This is a comparison diagram of the zeta potential of zeaxanthin nanoparticles prepared in Example 3 and Comparative Examples 2 to 9 of the present invention.

[0026] Figure 8 The image shows a comparison of the PDI of zeaxanthin nanoparticles prepared in Example 3 and Comparative Examples 2 to 9 of this invention.

[0027] exist Figures 6-8 In the examples, CZZ represents the zeaxanthin nanoparticles obtained in Example 3, PZZ represents the zeaxanthin nanoparticles obtained in Comparative Example 2, AZZ represents the zeaxanthin nanoparticles obtained in Comparative Example 3, PCZ represents the zeaxanthin nanoparticles obtained in Comparative Example 4, ACZ represents the zeaxanthin nanoparticles obtained in Comparative Example 5, CCZ represents the zeaxanthin nanoparticles obtained in Comparative Example 6, PSZ represents the zeaxanthin nanoparticles obtained in Comparative Example 7, ASZ represents the zeaxanthin nanoparticles obtained in Comparative Example 8, and CSZ represents the zeaxanthin nanoparticles obtained in Comparative Example 9. Detailed Implementation

[0028] To enable those skilled in the art to better understand and implement the technical solutions of this invention, the invention is further described below with reference to specific embodiments. However, the embodiments are not intended to limit the invention. Unless otherwise specified, the following test methods and detection methods are conventional methods; unless otherwise specified, the reagents and raw materials are commercially available.

[0029] To address the issue that commonly used wall materials for nanoparticles lack bioactivity, this invention provides zeaxanthin nanoparticles, their preparation method, and their applications.

[0030] The technical solution of the present invention will be described in detail below.

[0031] This invention provides zeaxanthin nanoparticles, comprising zeaxanthin, with its surface coated with zein to form protein nanoparticles. The protein nanoparticles are further coated with corn silk polysaccharide to form zeaxanthin nanoparticles with a particle size of 137 nm to 342 nm. The mass ratio of zeaxanthin, zein, and corn silk polysaccharide is 0.01:0.6–10:0.6–10. When the amount of zein added is less than the specified ratio, the nanoparticles do not completely encapsulate the zeaxanthin, resulting in a large amount of free zeaxanthin and wasting raw materials. When the amount of zein added is greater than the specified ratio, the excessive zein leads to uneven encapsulation of the zeaxanthin, causing inaccurate data results. When the amount of corn silk polysaccharide added is less than the specified ratio, the encapsulation effect of corn silk polysaccharide on zein is poor and the protective effect is weak; when the amount of corn silk polysaccharide added is greater than the specified ratio, the polysaccharide will cover the surface of zein with multiple layers, resulting in an increase in particle size and a poorer release effect.

[0032] In the above technical solution, zein and corn silk polysaccharide are sequentially wrapped around the outer layer of zeaxanthin to form a core-shell structure, thereby achieving the purpose of protecting zeaxanthin. The outermost layer of the zeaxanthin nanoparticles prepared in this invention, corn silk polysaccharide, is a water-soluble polysaccharide. While protecting zeaxanthin, it increases the solubility of the nanoparticles, further improving the utilization rate of zeaxanthin. The corn silk polysaccharide used in the nanoparticle system of this invention has better bioactivity; it can act as a prebiotic after release to achieve the purpose of lowering blood sugar, and it can also bind to zeaxanthin to enhance the effects of weight loss and lipid reduction. Compared with other types of polysaccharides, the use of corn silk polysaccharide to prepare nanoparticles in this invention is a more suitable delivery medium for zeaxanthin.

[0033] It should be noted that the encapsulation rate of zeaxanthin nanoparticles can reach 75.42% to 92.33% by coating the surface of zeaxanthin with protein nanoparticles formed by zeaxanthin gliadin and corn silk polysaccharides.

[0034] The present invention also provides a method for preparing the above-mentioned zeaxanthin nanoparticles, comprising the following steps: An ethanol solution of zeaxanthin was added to an ethanol solution of zein, and the mixture was stirred at 400 rpm to 600 rpm for 1 to 3 hours. Water was added for the first time to evaporate and remove the ethanol. Water was added for the second time, and the pH was adjusted to 4 to 5 using 0.01 M hydrochloric acid buffer to coat the zeaxanthin surface. The pH was then adjusted to 4.0 to 5.0 to obtain a protein nanoparticle solution.

[0035] A corn silk polysaccharide aqueous solution with a pH of 4-5 was mixed with the protein nanoparticle solution. Through a self-assembly reaction, the corn silk polysaccharide was coated onto the surface of the protein nanoparticles to obtain zeaxanthin nanoparticles.

[0036] In the preparation process of the zeaxanthin nanoparticles, since the ethanol solvent needs to be removed by rotary evaporation, the purpose of adding distilled water is to maintain a constant total volume of the solution. After stirring and mixing, a first mixture is obtained, and the volume ratio of the first mixture to the first added water is 1:1.8-3. After the first addition of water, a second mixture is obtained, and water is added a second time until the volume of the second mixture is equal to that of the second mixture. Adjusting the pH value to 4.0-5.0 can keep the protein nanoparticles in a better stable state.

[0037] The self-assembly reaction used in this invention is as follows: a corn silk polysaccharide aqueous solution with a pH of 4-5 is mixed with the protein nanoparticle solution and stirred at a speed of 400 rpm-600 rpm for 30 min-60 min to obtain zeaxanthin nanoparticles.

[0038] To obtain zeaxanthin nanoparticles with uniform particle size and good stability, after the self-assembly reaction is completed, a mixed solution is obtained, centrifuged at 3000 rpm to 4000 rpm for 10 min to 15 min to remove the precipitate, the supernatant is frozen at -40℃ to -30℃ for 14 h, and then dried at -25℃ to -20℃ for 10 h to obtain zeaxanthin nanoparticles.

[0039] The invention will now be described in detail through the following embodiments and comparative examples.

[0040] Example 1 A method for preparing zeaxanthin nanoparticles includes the following steps: S1. Dissolve 5 mg of zeaxanthin in 50 mL of anhydrous ethanol and stir magnetically at 500 rpm for 60 min at room temperature to obtain a zeaxanthin solution. Dissolve 0.1 g of zein in 100 mL of 75% ethanol solution and stir magnetically at 500 rpm for 60 min to obtain a zein solution. Slowly add 8 mL of the zeaxanthin solution to 20 mL of the zein solution and stir magnetically at 500 rpm for 2 h. Then, add distilled water to bring the volume to 80 mL. Remove the ethanol from the solution by rotary evaporation at 40 °C, and then add distilled water again to bring the volume to 80 mL. Adjust the pH to 4.0 using 0.01 M hydrochloric acid buffer to obtain a protein nanoparticle solution.

[0041] S2, 0.02 g of corn silk polysaccharide was dissolved in 100 mL of distilled water and magnetically stirred at 500 rpm for 60 min. The pH was then adjusted to 4.0 using 0.01 M hydrochloric acid buffer to obtain a corn silk polysaccharide solution. The corn silk polysaccharide was mixed with the protein nanoparticle solution, and the pH was adjusted to 4.0 using 0.01 M hydrochloric acid buffer. The mixture was then magnetically stirred at 500 rpm for 60 min to induce a self-assembly reaction and obtain a mixed solution. The mixed solution was centrifuged at 4000 rpm for 10 min to remove the precipitate. The supernatant was frozen at -40℃ for 14 h and then dried at -20℃ for 10 h to obtain zeaxanthin nanoparticles.

[0042] Example 2 A method for preparing zeaxanthin nanoparticles includes the following steps: S1. Dissolve 5 mg of zeaxanthin in 50 mL of anhydrous ethanol and stir magnetically at 500 rpm for 60 min at room temperature to obtain a zeaxanthin solution. Dissolve 0.06 g of zein in 100 mL of 75% ethanol solution and stir magnetically at 500 rpm for 60 min to obtain a zein solution. Slowly add 8 mL of the zeaxanthin solution to 20 mL of the zein solution and stir magnetically at 500 rpm for 2 h. Then, add distilled water to bring the volume to 80 mL. Remove the ethanol from the solution by rotary evaporation at 40 °C, and then add distilled water again to bring the volume to 80 mL. Adjust the pH to 4.0 using 0.01 M hydrochloric acid buffer to obtain a protein nanoparticle solution.

[0043] S2, 0.02 g of corn silk polysaccharide was dissolved in 100 mL of distilled water and magnetically stirred at 500 rpm for 60 min. The pH was then adjusted to 4.0 using 0.01 M hydrochloric acid buffer to obtain a corn silk polysaccharide solution. The corn silk polysaccharide was mixed with the protein nanoparticle solution, and the pH was adjusted to 4.0 using 0.01 M hydrochloric acid buffer. The mixture was then magnetically stirred at 500 rpm for 60 min to induce a self-assembly reaction and obtain a mixed solution. The mixed solution was centrifuged at 4000 rpm for 10 min to remove the precipitate. The supernatant was frozen at -40℃ for 14 h and then dried at -20℃ for 10 h to obtain zeaxanthin nanoparticles.

[0044] Example 3 A method for preparing zeaxanthin nanoparticles includes the following steps: S1. Dissolve 5 mg of zeaxanthin in 50 mL of anhydrous ethanol and stir magnetically at 500 rpm for 60 min at room temperature to obtain a zeaxanthin solution. Dissolve 0.1 g of zein in 100 mL of 75% ethanol solution and stir magnetically at 500 rpm for 60 min to obtain a zein solution. Slowly add 8 mL of the zeaxanthin solution to 20 mL of the zein solution and stir magnetically at 500 rpm for 2 h. Then, add distilled water to bring the volume to 80 mL. Remove the ethanol from the solution by rotary evaporation at 40 °C, and then add distilled water again to bring the volume to 80 mL. Adjust the pH to 4.0 using 0.01 M hydrochloric acid buffer to obtain a protein nanoparticle solution.

[0045] S2, 0.1 g of corn silk polysaccharide was dissolved in 100 mL of distilled water and magnetically stirred at 500 rpm for 60 min. The pH was then adjusted to 4.0 using 0.01 M hydrochloric acid buffer to obtain a corn silk polysaccharide solution. The corn silk polysaccharide was mixed with the protein nanoparticle solution and the pH was adjusted to 4.0 using 0.01 M hydrochloric acid buffer. The mixture was then magnetically stirred at 500 rpm for 60 min to induce a self-assembly reaction and obtain a mixed solution. The mixed solution was centrifuged at 4000 rpm for 10 min to remove the precipitate. The supernatant was frozen at -40℃ for 14 h and then dried at -20℃ for 10 h to obtain zeaxanthin nanoparticles.

[0046] Example 4 A method for preparing zeaxanthin nanoparticles includes the following steps: S1. Dissolve 5 mg of zeaxanthin in 50 mL of anhydrous ethanol and stir magnetically at 500 rpm for 60 min at room temperature to obtain a zeaxanthin solution. Dissolve 0.02 g of zein in 100 mL of 75% ethanol solution and stir magnetically at 500 rpm for 60 min to obtain a zein solution. Slowly add 8 mL of the zeaxanthin solution to 20 mL of the zein solution and stir magnetically at 500 rpm for 2 h. Then, add distilled water to bring the volume to 80 mL. Remove the ethanol from the solution by rotary evaporation at 40 °C, and then add distilled water again to bring the volume to 80 mL. Adjust the pH to 4.0 using 0.01 M hydrochloric acid buffer to obtain a protein nanoparticle solution.

[0047] S2, 0.06 g of corn silk polysaccharide was dissolved in 100 mL of distilled water and magnetically stirred at 500 rpm for 60 min. The pH was then adjusted to 4.0 using 0.01 M hydrochloric acid buffer to obtain a corn silk polysaccharide solution. The corn silk polysaccharide was mixed with the protein nanoparticle solution, and the pH was adjusted to 4.0 using 0.01 M hydrochloric acid buffer. The mixture was then magnetically stirred at 500 rpm for 60 min to induce a self-assembly reaction and obtain a mixed solution. The mixed solution was centrifuged at 4000 rpm for 10 min to remove the precipitate. The supernatant was frozen at -40℃ for 14 h and then dried at -20℃ for 10 h to obtain zeaxanthin nanoparticles.

[0048] Example 5 A method for preparing zeaxanthin nanoparticles includes the following steps: S1. Dissolve 5 mg of zeaxanthin in 50 mL of anhydrous ethanol and stir magnetically at 500 rpm for 60 min at room temperature to obtain a zeaxanthin solution. Dissolve 0.02 g of zein in 100 mL of 75% ethanol solution and stir magnetically at 500 rpm for 60 min to obtain a zein solution. Slowly add 8 mL of the zeaxanthin solution to 20 mL of the zein solution and stir magnetically at 500 rpm for 2 h. Then, add distilled water to bring the volume to 80 mL. Remove the ethanol from the solution by rotary evaporation at 40 °C, and then add distilled water again to bring the volume to 80 mL. Adjust the pH to 4.0 using 0.01 M hydrochloric acid buffer to obtain a protein nanoparticle solution.

[0049] S2, 0.1 g of corn silk polysaccharide was dissolved in 100 mL of distilled water and magnetically stirred at 500 rpm for 60 min. The pH was then adjusted to 4.0 using 0.01 M hydrochloric acid buffer to obtain a corn silk polysaccharide solution. The corn silk polysaccharide was mixed with the protein nanoparticle solution and the pH was adjusted to 4.0 using 0.01 M hydrochloric acid buffer. The mixture was then magnetically stirred at 500 rpm for 60 min to induce a self-assembly reaction and obtain a mixed solution. The mixed solution was centrifuged at 4000 rpm for 10 min to remove the precipitate. The supernatant was frozen at -40℃ for 14 h and then dried at -20℃ for 10 h to obtain zeaxanthin nanoparticles.

[0050] To further illustrate the technical effects of the present invention, a comparative example is also provided, as follows: Comparative Example 1 A method for preparing zeaxanthin nanoparticles includes the following steps: 5 mg of zeaxanthin was dissolved in 50 mL of anhydrous ethanol and magnetically stirred at 500 rpm for 60 min at room temperature to obtain a zeaxanthin solution. 0.1 g of zein was dissolved in 100 mL of 75% ethanol solution and magnetically stirred at 500 rpm for 60 min to obtain a zein solution. 8 mL of the zeaxanthin solution was slowly added dropwise to 20 mL of the zein solution, and the mixture was magnetically stirred at 500 rpm for 2 h. Distilled water was then added to bring the volume to 80 mL. The ethanol was removed by rotary evaporation at 40 °C, and distilled water was added again to bring the volume to 80 mL. The pH was adjusted to 4.0 using 0.01 M hydrochloric acid buffer to obtain a mixed solution. This mixed solution was centrifuged at 4000 rpm for 10 min to remove the precipitate. The supernatant was frozen at -40 °C for 14 h and then dried at -20 °C for 10 h to obtain zein-zeaxanthin nanoparticles, denoted as ZZ.

[0051] Comparative Example 2 A method for preparing zeaxanthin nanoparticles includes the following steps: S1. Dissolve 5 mg of zeaxanthin in 50 mL of anhydrous ethanol and stir magnetically at 500 rpm for 60 min at room temperature to obtain a zeaxanthin solution. Dissolve 0.1 g of zein in 100 mL of 75% ethanol solution and stir magnetically at 500 rpm for 60 min to obtain a zein solution. Slowly add 8 mL of the zeaxanthin solution to 20 mL of the zein solution and stir magnetically at 500 rpm for 2 h. Then, add distilled water to bring the volume to 80 mL. Remove the ethanol from the solution by rotary evaporation at 40 °C, and then add distilled water again to bring the volume to 80 mL. Adjust the pH to 4.0 using 0.01 M hydrochloric acid buffer to obtain a protein nanoparticle solution.

[0052] S2, 0.1g of Poria cocos polysaccharide was dissolved in 100mL of distilled water and magnetically stirred at 500rpm for 60min. The pH was then adjusted to 4.0 using 0.01M hydrochloric acid buffer to obtain a Poria cocos polysaccharide solution. The Poria cocos polysaccharide was mixed with the protein nanoparticle solution and the pH was adjusted to 4.0 using 0.01M hydrochloric acid buffer. The mixture was then magnetically stirred at 500rpm for 60min to induce a self-assembly reaction and obtain a mixed solution. The mixed solution was centrifuged at 4000rpm for 10min to remove the precipitate. The supernatant was frozen at -40℃ for 14h and then dried at -20℃ for 10h to obtain Poria cocos polysaccharide-zeaxanthin nanoparticles, i.e., zeaxanthin nanoparticles, denoted as PZZ.

[0053] Comparative Example 3 A method for preparing zeaxanthin nanoparticles includes the following steps: S1. Dissolve 5 mg of zeaxanthin in 50 mL of anhydrous ethanol and stir magnetically at 500 rpm for 60 min at room temperature to obtain a zeaxanthin solution. Dissolve 0.1 g of zein in 100 mL of 75% ethanol solution and stir magnetically at 500 rpm for 60 min to obtain a zein solution. Slowly add 8 mL of the zeaxanthin solution to 20 mL of the zein solution and stir magnetically at 500 rpm for 2 h. Then, add distilled water to bring the volume to 80 mL. Remove the ethanol from the solution by rotary evaporation at 40 °C, and then add distilled water again to bring the volume to 80 mL. Adjust the pH to 4.0 using 0.01 M hydrochloric acid buffer to obtain a protein nanoparticle solution.

[0054] S2, 0.1 g of Astragalus polysaccharide was dissolved in 100 mL of distilled water and magnetically stirred at 500 rpm for 60 min. The pH was then adjusted to 4.0 using 0.01 M hydrochloric acid buffer to obtain an Astragalus polysaccharide solution. The Astragalus polysaccharide solution was mixed with the protein nanoparticle solution and the pH was adjusted to 4.0 using 0.01 M hydrochloric acid buffer. The mixture was then magnetically stirred at 500 rpm for 60 min to induce a self-assembly reaction and obtain a mixed solution. The mixed solution was centrifuged at 4000 rpm for 10 min to remove the precipitate. The supernatant was frozen at -40℃ for 14 h and then dried at -20℃ for 10 h to obtain Astragalus polysaccharide-zeaxanthin nanoparticles, i.e., zeaxanthin nanoparticles, denoted as AZZ.

[0055] Comparative Example 4 A method for preparing zeaxanthin nanoparticles includes the following steps: S1. Dissolve 5 mg of zeaxanthin in 50 mL of anhydrous ethanol and stir magnetically at 500 rpm for 60 min at room temperature to obtain a zeaxanthin solution. Dissolve 0.1 g of chickpea protein in 100 mL of 75% ethanol solution and stir magnetically at 500 rpm for 60 min to obtain a chickpea protein solution. Slowly add 8 mL of the zeaxanthin solution to 20 mL of the chickpea protein solution and stir magnetically at 500 rpm for 2 h. Then, add distilled water to bring the volume to 80 mL. Remove the ethanol from the solution by rotary evaporation at 40 °C, and then add distilled water again to bring the volume to 80 mL. Adjust the pH to 4.0 using 0.01 M hydrochloric acid buffer to obtain a protein nanoparticle solution.

[0056] S2, 0.1g of Poria cocos polysaccharide was dissolved in 100mL of distilled water and magnetically stirred at 500rpm for 60min. The pH was then adjusted to 4.0 using 0.01M hydrochloric acid buffer to obtain a Poria cocos polysaccharide solution. The Poria cocos polysaccharide was mixed with the protein nanoparticle solution and the pH was adjusted to 4.0 using 0.01M hydrochloric acid buffer. The mixture was then magnetically stirred at 500rpm for 60min to induce a self-assembly reaction and obtain a mixed solution. The mixed solution was centrifuged at 4000rpm for 10min to remove the precipitate. The supernatant was frozen at -40℃ for 14h and then dried at -20℃ for 10h to obtain Poria cocos polysaccharide-chickpea protein nanoparticles, i.e., zeaxanthin nanoparticles, denoted as PCZ.

[0057] Comparative Example 5 A method for preparing zeaxanthin nanoparticles includes the following steps: S1. Dissolve 5 mg of zeaxanthin in 50 mL of anhydrous ethanol and stir magnetically at 500 rpm for 60 min at room temperature to obtain a zeaxanthin solution. Dissolve 0.1 g of chickpea protein in 100 mL of 75% ethanol solution and stir magnetically at 500 rpm for 60 min to obtain a chickpea protein solution. Slowly add 8 mL of zeaxanthin solution to 20 mL of chickpea protein solution and stir magnetically at 500 rpm for 2 h. Then, add distilled water to bring the volume to 80 mL. Remove the ethanol from the solution by rotary evaporation at 40 °C, and then add distilled water again to bring the volume to 80 mL. Adjust the pH to 4.0 using 0.01 M hydrochloric acid buffer to obtain a protein nanoparticle solution.

[0058] S2, 0.1 g of Astragalus polysaccharide was dissolved in 100 mL of distilled water and magnetically stirred at 500 rpm for 60 min. The pH was then adjusted to 4.0 using 0.01 M hydrochloric acid buffer to obtain an Astragalus polysaccharide solution. The Astragalus polysaccharide solution was mixed with the protein nanoparticle solution and the pH was adjusted to 4.0 using 0.01 M hydrochloric acid buffer. The mixture was then magnetically stirred at 500 rpm for 60 min to induce a self-assembly reaction and obtain a mixed solution. The mixed solution was centrifuged at 4000 rpm for 10 min to remove the precipitate. The supernatant was frozen at -40℃ for 14 h and then dried at -20℃ for 10 h to obtain Astragalus polysaccharide-chickpea protein nanoparticles, i.e., zeaxanthin nanoparticles, denoted as ACZ.

[0059] Comparative Example 6 A method for preparing zeaxanthin nanoparticles includes the following steps: S1. Dissolve 5 mg of zeaxanthin in 50 mL of anhydrous ethanol and stir magnetically at 500 rpm for 60 min at room temperature to obtain a zeaxanthin solution. Dissolve 0.1 g of chickpea protein in 100 mL of 75% ethanol solution and stir magnetically at 500 rpm for 60 min to obtain a chickpea protein solution. Slowly add 8 mL of the zeaxanthin solution to 20 mL of the chickpea protein solution and stir magnetically at 500 rpm for 2 h. Then, add distilled water to bring the volume to 80 mL. Remove the ethanol from the solution by rotary evaporation at 40 °C, and then add distilled water again to bring the volume to 80 mL. Adjust the pH to 4.0 using 0.01 M hydrochloric acid buffer to obtain a protein nanoparticle solution.

[0060] S2, 0.1 g of corn silk polysaccharide was dissolved in 100 mL of distilled water and magnetically stirred at 500 rpm for 60 min. The pH was then adjusted to 4.0 using 0.01 M hydrochloric acid buffer to obtain a corn silk polysaccharide solution. The corn silk polysaccharide was mixed with the protein nanoparticle solution and the pH was adjusted to 4.0 using 0.01 M hydrochloric acid buffer. The mixture was then magnetically stirred at 500 rpm for 60 min to induce a self-assembly reaction and obtain a mixed solution. The mixed solution was centrifuged at 4000 rpm for 10 min to remove the precipitate. The supernatant was frozen at -40℃ for 14 h and then dried at -20℃ for 10 h to obtain corn silk polysaccharide-chickpea protein nanoparticles, i.e., zeaxanthin nanoparticles, denoted as CCZ.

[0061] Comparative Example 7 A method for preparing zeaxanthin nanoparticles includes the following steps: S1. Dissolve 5 mg of zeaxanthin in 50 mL of anhydrous ethanol and stir magnetically at 500 rpm for 60 min at room temperature to obtain a zeaxanthin solution. Dissolve 0.1 g of soy protein isolate in 100 mL of 75% ethanol solution and stir magnetically at 500 rpm for 60 min to obtain a soy protein isolate solution. Slowly add 8 mL of the zeaxanthin solution to 20 mL of the soy protein isolate solution and stir magnetically at 500 rpm for 2 h. Then, add distilled water to bring the volume to 80 mL. Remove the ethanol from the solution by rotary evaporation at 40 °C, and then add distilled water again to bring the volume to 80 mL. Adjust the pH to 4.0 using 0.01 M hydrochloric acid buffer to obtain a protein nanoparticle solution.

[0062] S2, 0.1g of Poria cocos polysaccharide was dissolved in 100mL of distilled water and magnetically stirred at 500rpm for 60min. The pH was then adjusted to 4.0 using 0.01M hydrochloric acid buffer to obtain a Poria cocos polysaccharide solution. The Poria cocos polysaccharide was mixed with the protein nanoparticle solution and the pH was adjusted to 4.0 using 0.01M hydrochloric acid buffer. The mixture was then magnetically stirred at 500rpm for 60min to induce a self-assembly reaction and obtain a mixed solution. The mixed solution was centrifuged at 4000rpm for 10min to remove the precipitate. The supernatant was frozen at -40℃ for 14h and then dried at -20℃ for 10h to obtain Poria cocos polysaccharide-soybean protein isolate nanoparticles, i.e., zeaxanthin nanoparticles, denoted as PSZ.

[0063] Comparative Example 8 A method for preparing zeaxanthin nanoparticles includes the following steps: S1. Dissolve 5 mg of zeaxanthin in 50 mL of anhydrous ethanol and stir magnetically at 500 rpm for 60 min at room temperature to obtain a zeaxanthin solution. Dissolve 0.1 g of soy protein isolate in 100 mL of 75% ethanol solution and stir magnetically at 500 rpm for 60 min to obtain a soy protein isolate solution. Slowly add 8 mL of the zeaxanthin solution to 20 mL of the soy protein isolate solution and stir magnetically at 500 rpm for 2 h. Then, add distilled water to bring the volume to 80 mL. Remove the ethanol from the solution by rotary evaporation at 40 °C, and then add distilled water again to bring the volume to 80 mL. Adjust the pH to 4.0 using 0.01 M hydrochloric acid buffer to obtain a protein nanoparticle solution.

[0064] S2, 0.1 g of Astragalus polysaccharide was dissolved in 100 mL of distilled water and magnetically stirred at 500 rpm for 60 min. The pH was then adjusted to 4.0 using 0.01 M hydrochloric acid buffer to obtain an Astragalus polysaccharide solution. The Astragalus polysaccharide solution was mixed with the protein nanoparticle solution and the pH was adjusted to 4.0 using 0.01 M hydrochloric acid buffer. The mixture was then magnetically stirred at 500 rpm for 60 min to induce a self-assembly reaction and obtain a mixed solution. The mixed solution was centrifuged at 4000 rpm for 10 min to remove the precipitate. The supernatant was frozen at -40℃ for 14 h and then dried at -20℃ for 10 h to obtain Astragalus polysaccharide-soybean protein isolate nanoparticles, i.e., zeaxanthin nanoparticles, denoted as ASZ.

[0065] Comparative Example 9 A method for preparing zeaxanthin nanoparticles includes the following steps: S1. Dissolve 5 mg of zeaxanthin in 50 mL of anhydrous ethanol and stir magnetically at 500 rpm for 60 min at room temperature to obtain a zeaxanthin solution. Dissolve 0.1 g of soy protein isolate in 100 mL of 75% ethanol solution and stir magnetically at 500 rpm for 60 min to obtain a soy protein isolate solution. Slowly add 8 mL of the zeaxanthin solution to 20 mL of the soy protein isolate solution and stir magnetically at 500 rpm for 2 h. Then, add distilled water to bring the volume to 80 mL. Remove the ethanol from the solution by rotary evaporation at 40 °C, and then add distilled water again to bring the volume to 80 mL. Adjust the pH to 4.0 using 0.01 M hydrochloric acid buffer to obtain a protein nanoparticle solution.

[0066] S2, 0.1 g of corn silk polysaccharide was dissolved in 100 mL of distilled water and magnetically stirred at 500 rpm for 60 min. The pH was then adjusted to 4.0 using 0.01 M hydrochloric acid buffer to obtain a corn silk polysaccharide solution. The corn silk polysaccharide was mixed with the protein nanoparticle solution and the pH was adjusted to 4.0 using 0.01 M hydrochloric acid buffer. The mixture was then magnetically stirred at 500 rpm for 60 min to induce a self-assembly reaction and obtain a mixed solution. The mixed solution was centrifuged at 4000 rpm for 10 min to remove the precipitate. The supernatant was frozen at -40℃ for 14 h and then dried at -20℃ for 10 h to obtain corn silk polysaccharide-soybean protein isolate nanoparticles, i.e., zeaxanthin nanoparticles, denoted as CSZ.

[0067] The performance of the zeaxanthin nanoparticles provided in the above embodiments and comparative examples was tested, and the testing process and results are as follows.

[0068] 1 mg of zeaxanthin was dissolved in 10 mL of anhydrous ethanol and vortexed to obtain a 100 μg / mL zeaxanthin solution. This solution was then diluted 2, 4, 8, 16, 32, and 64 times to obtain zeaxanthin solutions of different concentrations. The absorbance of each solution was measured at 450 nm to obtain a standard curve. Zeaxanthin nanoparticles were dissolved in anhydrous ethanol, sonicated at 400 W for 15 min, and centrifuged at 4000 rpm for 10 min. The supernatant was retained, and this process was repeated three times. The absorbance of the retained supernatant was measured at 450 nm, and the result was substituted into the zeaxanthin standard curve to obtain the encapsulation efficiency of the nanoparticles.

[0069] In vivo experiments: Grouping, Modeling, and Drug Administration: Thirty-six male C57 / 6J mice were fasted for 12 hours before the experiment but allowed free access to water. The mice were randomly divided into six groups of six: a control group, a model group, an orlistat positive control group (30 mg / kg), a corn silk polysaccharide (CSP) group (300 mg / kg), a zeaxanthin (ZEA) group (300 mg / kg), and a zeaxanthin nanoparticle group (300 mg / kg). Except for the control group, all other groups were fed a high-fat diet. During the experiment, animals had free access to water and food. Modeling was considered successful when the average body weight of all groups exceeded the control group's body weight by 30%, at which point drug administration began. The control and model groups received the same amount of physiological saline for six consecutive weeks. Body weight was measured three times per week, and the drug dosage was adjusted accordingly.

[0070] The high-fat feed formula is as follows: casein 25.8%, cystine 3%, maltodextrin 16.1%, sucrose 8.8%, cellulose 6.4%, soybean oil 3.2%, lard 31.6%, S10026B mineral mixture 1.2%, V10001C vitamin mixture 3.7%, and choline tartrate 0.2%. The high-fat feed was purchased from Jiangsu Xietong Pharmaceutical Biotechnology Co., Ltd.

[0071] Sample collection: At the end of week 12, mice in each group were fasted for 12 hours, their body weight was measured and they were sacrificed. Blood, liver and epididymal fat samples were collected. After the blood was allowed to stand for 2 hours, it was centrifuged at 3500 rpm for 10 minutes at 4°C. The serum was then stored at -80°C for later use.

[0072] Indicator detection: The weight of liver and epididymal fat was measured. Serum TC and TG levels were detected using appropriate kits. Pathological observation of mouse liver tissue was also performed.

[0073] Statistical methods: All data were processed using SPSS 28.0 statistical software, and graphs were generated using Origin 2021 and Graphpad Pism 9.5 software.

[0074] Experimental results: 1. The particle size, potential, and dispersibility of the zeaxanthin nanoparticles prepared in the examples and comparative examples were analyzed by particle size, zeta potential, and PDI. Figures 1-3 As shown, the zeaxanthin nanoparticles coated with corn silk polysaccharide and corn gliadin prepared in Examples 1 to 5 of the present invention are the best. Among them, the zeaxanthin nanoparticles prepared in Example 3 have the smallest particle size and the lowest PDI, indicating that the zeaxanthin nanoparticles prepared in Example 3 of the present invention have the best solubility and dispersibility; the absolute value of the Zeta potential is the largest, indicating that the zeaxanthin nanoparticles have the best stability at this time.

[0075] 2. Particle size analysis, such as Figure 6 As shown, the particle size of nanoparticles was determined by a Malvern particle size analyzer. Finally, it was found that when the ratio of corn silk polysaccharide to corn gliadin was 1:1, the particle size of zeaxanthin nanoparticles was the smallest, at 137 nm.

[0076] 3. Potential analysis, such as Figure 7 As shown, the potential of nanoparticles was measured using a Malvern particle size analyzer. The results showed that the absolute value of the potential of zeaxanthin nanoparticles was the largest, -25.19, when the ratio of corn silk polysaccharide to corn gliadin was 1:1. At this ratio, the stability of zeaxanthin nanoparticles was the best.

[0077] 4. PDI analysis, such as Figure 8As shown, the PDI value of nanoparticles was determined by a Malvern particle size analyzer. The results showed that the PDI value of zeaxanthin nanoparticles was the lowest at 0.087 when the ratio of corn silk polysaccharide to corn gliadin was 1:1, indicating that the dispersibility of the zeaxanthin nanoparticle solution was the best at this ratio.

[0078] 5. Encapsulation efficiency: The standard curve for zeaxanthin was calculated after measurement as follows: y = 0.058x + 0.3499; After substituting the values ​​into the standard curve calculation, as follows: Figure 4 As shown, when the ratio of corn silk polysaccharide to corn gliadin is 1:1, the encapsulation efficiency of zeaxanthin nanoparticles reaches the maximum of 92.33%.

[0079] 6. Nanoparticles can reduce the body weight of obese mice by 11.0g–16.0g, reduce liver weight by 0.35g–0.67g, and reduce epididymal fat weight by 0.83g–2.01g. For example... Figure 5 As shown, zeaxanthin nanoparticles, compared to polysaccharides and zeaxanthin alone, are more effective in slowing down liver tissue lesions and fat accumulation in the liver tissue of obese mice.

[0080] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A zeaxanthin nanoparticle, characterized in that, It is made of a core material and a first wall material and a second wall material sequentially covering the surface of the core material; the core material is zeaxanthin, the first wall material is zein, and the second wall material is corn silk polysaccharide; The mass ratio of zeaxanthin, zeaxanthin and zeaxanthin polysaccharide is 0.01:0.6-10:0.6-10.

2. The zeaxanthin nanoparticles according to claim 1, characterized in that, The zeaxanthin nanoparticles have a particle size of 137 nm to 342 nm.

3. The zeaxanthin nanoparticles according to claim 1, characterized in that, The encapsulation efficiency of the zeaxanthin nanoparticles is 75.42%–92.33%.

4. A method for preparing zeaxanthin nanoparticles according to claim 1, characterized in that, Includes the following steps: An ethanol solution of zeaxanthin was added to an ethanol solution of zein and stirred to mix. Water was added for the first time to evaporate and remove the ethanol. Water was added for the second time to adjust the pH to 4-5, so that zein coated the surface of zeaxanthin and a protein nanoparticle solution was obtained. A corn silk polysaccharide aqueous solution with a pH of 4-5 was mixed with the protein nanoparticle solution. Through a self-assembly reaction, the corn silk polysaccharide was coated onto the surface of the protein nanoparticles to obtain zeaxanthin nanoparticles.

5. The method for preparing zeaxanthin nanoparticles according to claim 4, characterized in that, After stirring and mixing, a first mixture is obtained, and the volume ratio of the first mixture to the water added for the first time is 1:1.8 to 3.

6. The method for preparing zeaxanthin nanoparticles according to claim 4, characterized in that, The stirring is performed at a speed of 400 rpm to 600 rpm for 1 to 3 hours.

7. The method for preparing zeaxanthin nanoparticles according to claim 4, characterized in that, The mass ratio of zein to corn silk polysaccharide is 1:

1.

8. The method for preparing zeaxanthin nanoparticles according to claim 4, characterized in that, The self-assembly reaction is as follows: a corn silk polysaccharide aqueous solution with a pH of 4-5 is mixed with the protein nanoparticle solution and stirred at a speed of 400 rpm-600 rpm for 30 min-60 min to obtain zeaxanthin nanoparticles.

9. The method for preparing zeaxanthin nanoparticles according to claim 4, characterized in that, After the self-assembly reaction is completed, a mixed solution is obtained. The solution is centrifuged at 3000 rpm to 4000 rpm for 10 min to 15 min to remove the precipitate. The supernatant is then freeze-dried to obtain zeaxanthin nanoparticles.

10. The use of zeaxanthin nanoparticles according to any one of claims 1 to 3 in the preparation of a drug for regulating glucose and lipid metabolism.

Images