A polyphenol sustained-release microcapsule and a preparation method thereof

Abstract

The application provides a kind of polyphenol sustained-release microcapsule and its preparation method, it is related to the technical field of pharmaceutical excipients.The polyphenol sustained-release microcapsule is composed of core material and wall material, the core material is coffee powder extract, the wall material is composed of the following raw materials: gum arabic, beta-cyclodextrin, monoglyceride, pregelatinized oat protein, modified soybean fiber;The mass ratio of the pregelatinized oat protein and beta-cyclodextrin is less than or equal to 1.75.The application uses the combination of traditional outer wall material gum arabic and beta-cyclodextrin as the base material, ensures that a certain degree of wrapping is first achieved, and additionally adds pregelatinized oat protein and modified soybean fiber.The pregelatinization treatment increases the solubility of oat protein, exposes more hydrophobic groups, significantly enhances the adsorption capacity of protein at the oil-water interface, combines with the mixed solution formed by gum arabic, beta-cyclodextrin and monoglyceride, forms a wall material with strong interfacial force and maintains the sustained-release effect in gastric juice, and improves the targeted sustained-release effect of the sustained-release microcapsule.

Description

Technical Field

[0001] This invention relates to the field of pharmaceutical excipient preparation technology, specifically to a polyphenol sustained-release microcapsule and its preparation method. Background Technology

[0002] Polyphenols are active ingredients widely found in everyday fruits and vegetables and other natural resources. They have significant antioxidant and antibacterial physiological functions and are considered mild and effective natural antioxidants with important potential in preventing chronic diseases such as diabetes, cardiovascular disease, and cancer.

[0003] Extensive research has been conducted both domestically and internationally on polyphenol sustained-release microcapsules. For example, early studies using ethyl cellulose (EC) as a matrix and employing emulsion solvent evaporation technology to prepare polyphenol microcapsules demonstrated that this process does not damage the polyphenol components and improves their stability and sustained-release effect. The choice of wall material directly affects the encapsulation efficiency and sustained-release behavior of microcapsules. Different wall materials (such as β-cyclodextrin, pectin-chitosan composite wall materials, and soybean protein-maltodextrin) vary significantly in appearance, solubility, and sustained-release curves. While some wall material combinations achieve high encapsulation efficiency, the wall materials of ordinary microcapsules are easily destroyed in the acidic environment of gastric juice, leading to premature leakage and release of a large amount of core material, failing to achieve the expected effect of targeted delivery of polyphenols to the intestines followed by gradual release. For instance, studies have shown that loquat flower polyphenol microcapsules using pectin, sodium alginate, and chitosan as wall materials, while controlling the gastric juice release rate to approximately 19.59%, still exhibit higher release rates in gastric juice with many other traditional methods, failing to meet the requirements for targeted sustained release in the intestines. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a polyphenol sustained-release microcapsule and its preparation method, which can improve the targeted sustained-release effect.

[0005] To achieve the above objectives, the present invention provides the following technical solution: A polyphenol sustained-release microcapsule is composed of a core material and a wall material. The core material is a coffee powder extract, and the wall material is composed of the following raw materials in parts by weight: 40-60 parts of gum arabic, 10-20 parts of β-cyclodextrin, 1-2 parts of monoglyceride, 15-25 parts of pregelatinized oat protein, and 2-5 parts of modified soybean fiber. The mass ratio of the pregelatinized oat protein to β-cyclodextrin is ≤1.75.

[0006] Preferably, the preparation steps of the oat protein are as follows: S1. Wash and dry the oat grains, steam for 15-20 minutes, and then stir-fry to obtain oat flour with a gelatinization degree of 30-32%. S2. Degrease oat flour with n-hexane for 4-6 hours, centrifuge, precipitate, and dry to obtain defatted oat flour; S3. Add defatted oat flour to NaOH solution, adjust pH, stir in water bath, centrifuge, adjust pH, let stand to separate layers, centrifuge, precipitate, adjust pH to neutral, freeze dry, grind and sieve to obtain oat protein.

[0007] Preferably, the frying temperature in step S1 is 160-180℃, and the frying time is 30-40 minutes.

[0008] Preferably, the centrifugation speed in step S2 is 4000-5000 r / min.

[0009] Preferably, the concentration of the NaOH solution in step S3 is 0.01 mol / L.

[0010] The steps of a method for preparing polyphenol sustained-release microcapsules are as follows: (1) Dissolve gum arabic and β-cyclodextrin in distilled water, then add monoglyceride to obtain a mixture; (2) Add pregelatinized oat protein and modified soybean fiber to the mixture, mix well, and form a wall material solution; (3) Dissolve coffee powder extract in anhydrous ethanol, pour it into the wall material solution while stirring, emulsify, spray dry to obtain sustained-release microcapsules.

[0011] Preferably, the mass ratio of gum arabic and β-cyclodextrin to distilled water in step (1) is 1:12-14, and the temperature of the distilled water is 50-60℃.

[0012] Preferably, the mass ratio of coffee powder extract to wall material solution in step (2) is 1:3-4.

[0013] This invention provides a polyphenol sustained-release microcapsule and its preparation method, which has the following advantages compared with the prior art: This invention uses a combination of traditional outer wall materials, gum arabic and β-cyclodextrin, as the base material. To ensure a certain degree of encapsulation, pregelatinized oat protein and modified soybean fiber are added. The pregelatinization process increases the solubility of oat protein and exposes more hydrophobic groups, which significantly enhances the protein's adsorption capacity at the oil-water interface. This material combines with a mixture of gum arabic, β-cyclodextrin, and monoglycerides to form a wall material with strong interfacial forces that maintains a sustained-release effect in gastric juice, thus comprehensively improving the targeted sustained-release effect of the sustained-release microcapsules. Attached Figure Description

[0014] Figure 1 Line graph showing the polyphenol release rate of sustained-release microcapsules in artificial gastric fluid; Figure 2 Line graph showing the polyphenol release rate of sustained-release microcapsules in artificial intestinal fluid. Detailed Implementation

[0015] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0016] Unless otherwise specified, all reagents used in the following schemes are commercially available products.

[0017] Coffee powder extract (polyphenols) was purchased from Xi'an Feida Biotechnology Co., Ltd.; modified soybean fiber was purchased from Jiangsu Dongju Biotechnology Co., Ltd.

[0018] Preparation of pregelatinized oat protein: Pregelatinized oat protein A: S1. After washing and drying the oat grains, steam them for 18 minutes, stir-fry them at 170℃ for 35 minutes, grind them, and obtain oat flour with a gelatinization degree of 31%. S2. Degrease oat flour with n-hexane for 5 hours. The ratio of n-hexane to oat flour is 1:3. Centrifuge at 4500 r / min for 2 minutes, precipitate, and dry to obtain defatted oat flour. S3. Add defatted oat flour to a 0.01 mol / L NaOH solution, with a material-to-liquid ratio of defatted oat flour to NaOH solution of 1:10. Adjust the pH to 10.5, stir in a water bath for 2 hours, centrifuge at 4500 r / min for 10 minutes, take the supernatant, adjust the pH to 4.5, let it stand to separate into layers, centrifuge at 4500 r / min for 10 minutes, precipitate, adjust the pH to 7.0, freeze dry, grind and pass through a 10-mesh sieve to obtain pregelatinized oat protein A.

[0019] Pregelatinized oat protein B: The preparation of pregelatinized oat protein B is the same as that of pregelatinized oat protein A, except that the cooking step is omitted. Specifically: S1. Wash and dry the oat grains, then roast them at 170℃ for 25 minutes, grind them, and obtain oat flour with a gelatinization degree of 31%.

[0020] Pregelatinized oat protein C: The preparation of pregelatinized oat protein C is the same as that of pregelatinized oat protein A, except that the roasting step is omitted. Specifically: S1. Wash and dry the oat grains, then steam for 18 minutes, dry, and grind to obtain oat flour.

[0021] Example 1 A method for preparing polyphenol sustained-release microcapsules: S1. The wall material solution is prepared according to the following parts by weight of raw materials: 60 parts of gum arabic, 10 parts of β-cyclodextrin, 2 parts of monoglyceride, 17.5 parts of pregelatinized oat protein A, and 2 parts of modified soybean fiber; S2. Dissolve gum arabic and β-cyclodextrin in distilled water at a mass ratio of 1:13. Then add monoglyceride, heat to 55°C, and let stand for 6 hours to obtain a mixture. S3. Add pregelatinized oat protein A and modified soybean fiber to the mixture, mix well, and form a wall material solution. S4. Dissolve the coffee powder extract in anhydrous ethanol. The mass ratio of the coffee powder extract to the wall material solution is 1:3.5. Pour the solution into the wall material solution while stirring. Emulsify and spray dry at 180°C to obtain sustained-release microcapsules.

[0022] Example 2 S1, 40 parts gum arabic, 12 parts β-cyclic paste, 1 part monoglyceride, 20.4 parts pregelatinized oat protein, and 5 parts modified soybean fiber.

[0023] Comparative Example 1 This comparative example follows the preparation method of Example 1, except that the pregelatinized oat protein A is replaced with untreated oat protein, and all other steps are the same.

[0024] Comparative Example 2 This comparative example follows the preparation method of Example 1, except that pregelatinized oat protein A is replaced with pregelatinized oat protein B, and all other steps are the same.

[0025] Comparative Example 3 This comparative example follows the preparation method of Example 1, except that pregelatinized oat protein A is replaced with pregelatinized oat protein C, and all other steps are the same.

[0026] Comparative Example 4 This comparative example follows the preparation method of Example 1, except that the mass ratio of pregelatinized oat protein to β-cyclodextrin is >1.75, and all other steps are the same.

[0027] Comparative Example 5 This comparative example follows the preparation method of Example 1, only adjusting step S2 and eliminating step S3; all other steps are the same, specifically: S2. Dissolve gum arabic and β-cyclodextrin in distilled water at a mass ratio of 1:13. Then add monoglyceride, pregelatinized oat protein A, and modified soybean fiber. Heat to 55°C and let stand for 6 hours to obtain the wall material solution.

[0028] Comparative Example 6 This comparative example follows the preparation method of Example 1, except that step S2 is adjusted, while all other steps are the same, specifically: S2. Dissolve gum arabic and β-cyclodextrin in distilled water at a mass ratio of 1:13. Then add monoglyceride to obtain a mixture.

[0029] Detection The sustained-release microcapsules prepared according to the preparation methods of Examples 1-2 and Comparative Examples 1-6 were used as samples for the following tests; 1. Encapsulation rate determination The polyphenol content on the surface of the microcapsules was determined by the Folin-Ciocalteu method. The encapsulation efficiency was calculated as shown in formula (1), and the specific results are shown in Table 1. Encapsulation rate (%) = (1) Table 1 From the data in Table 1 above, the following conclusions can be drawn: The test sample prepared in Example 1 had the best encapsulation rate. Based on the single comparison principle, after replacing Comparative Example 1 with ordinary oat protein, the encapsulation rate decreased by 5.01%, indicating that adding gelatinized oat protein can have a positive effect. For the preparation of gelatinized protein powder, Comparative Examples 2 and 3 were set up for comparison. Comparative Examples 2 and 3 showed decreases of 10.27% and 14.94%, respectively, indicating that adding gelatinized oat protein A to the reaction system according to the preparation method can effectively improve the encapsulation rate of microcapsules.

[0030] 2. Release status in gastric juice Accurately weigh 100 mg of the dried microcapsule sample and add it to 40 mL of artificial gastric fluid. Incubate at 37 ℃ with shaking for 3 h. Take 1 mL of the supernatant every h, centrifuge at 60 r / min, and simultaneously replenish with an equal volume of artificial gastric fluid. Take the supernatant, determine the polyphenol content in the gastric fluid, and calculate its release rate in the gastric fluid. The calculation is shown in formula (2). Specific results are as follows: Figure 1 As shown in Table 2: Release rate (%) = (2) Table 2 From the data in Table 2 above, the following conclusions can be drawn: The microcapsule sample prepared in Example 1 had the lowest release rate in gastric juice. Comparative Example 1 showed a smaller increase in release rate at 1 hour compared to other comparative examples (except Comparative Example 4), but its release rate increased rapidly at 2 hours, increasing by 7.92%, indicating unstable release. Comparative Example 3 maintained a high polyphenol release rate at 1 hour, reaching 24.63% at 3 hours, indicating a high release rate. Among the comparative examples, Comparative Example 4 had the lowest release rate, except for Examples 1 and 2, meaning that the release rate in gastric juice did not change significantly after changing the ratio of gelatinized oat protein to β-cyclodextrin.

[0031] 3. Release status in intestinal fluid Add 0.2 g of lyophilized saponin microcapsule sample to 40 mL of artificial intestinal fluid and shake at 37 ℃ for 4 h. Take 1 mL of supernatant every 1 h, centrifuge at 60 r / min, and add an equal volume of artificial intestinal fluid at the same time. Take the supernatant, determine the polyphenol content in the intestinal fluid and calculate its release rate in the intestinal fluid. The calculation is shown in formula (3). The specific results are as follows. Figure 2 As shown in Table 3: Release rate (%) = (3) Table 3 The data in Table 3 above lead to the following conclusions: Example 1 exhibits the highest release rate in the small intestine. Combined with Table 2, although Comparative Example 4 shows a lower release rate in gastric juice, its release rate in the small intestine is also relatively low, failing to meet the requirements for targeted sustained release in the intestine.

[0032] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A polyphenol sustained-release microcapsule, comprising a core material and a wall material, wherein the core material is a coffee powder extract, characterized in that, The wall material is composed of the following raw materials in parts by weight: 40-60 parts gum arabic, 10-20 parts β-cyclodextrin, 1-2 parts monoglyceride, 15-25 parts pregelatinized oat protein, and 2-5 parts modified soybean fiber. The mass ratio of the pregelatinized oat protein to β-cyclodextrin is ≤1.

75.

2. The polyphenol sustained-release microcapsule according to claim 1, characterized in that, The preparation steps of the oat protein are as follows: S1. Wash and dry the oat grains, steam for 15-20 minutes, stir-fry, grind, and obtain oat flour with a gelatinization degree of 30-32%. S2. Degrease oat flour with n-hexane for 4-6 hours, centrifuge, precipitate, and dry to obtain defatted oat flour; S3. Add defatted oat flour to NaOH solution, adjust pH, stir in water bath, centrifuge, adjust pH, let stand to separate layers, centrifuge, precipitate, adjust pH to neutral, freeze dry, grind and sieve to obtain oat protein.

3. The polyphenol sustained-release microcapsule according to claim 1, characterized in that, The frying temperature in step S1 is 160-180℃, and the frying time is 30-40 minutes.

4. The polyphenol sustained-release microcapsule according to claim 1, characterized in that, The centrifugation speed mentioned in step S2 is 4000-5000 r / min.

5. The polyphenol sustained-release microcapsule according to claim 1, characterized in that, The concentration of the NaOH solution mentioned in step S3 is 0.01 mol / L.

6. A method for preparing polyphenol sustained-release microcapsules as described in any one of claims 1-5, characterized in that, The specific preparation steps are as follows: (1) Dissolve gum arabic and β-cyclodextrin in distilled water, then add monoglyceride, heat to 50-60℃, and let stand for 5-8 hours to obtain a mixture; (2) Add pregelatinized oat protein and modified soybean fiber to the mixture, mix well, and form a wall material solution; (3) Dissolve the coffee powder extract in anhydrous ethanol, pour it into the wall material solution while stirring, emulsify, spray dry, and obtain sustained-release microcapsules.

7. The preparation method according to claim 6, characterized in that, The mass ratio of gum arabic and β-cyclodextrin to distilled water in step (1) is 1:12-14, and the temperature of the distilled water is 50-60℃.

8. The preparation method according to claim 6, characterized in that, The mass ratio of coffee powder extract to wall material solution in step (2) is 1:3-4.

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