Efficient preparation of capsaicin and construction of starch-based nanoparticle delivery carrier of capsaicin

Abstract

The invention relates to the technical field of targeted food preparation, and particularly discloses efficient preparation of capsaicin and construction of a starch-based nanoparticle delivery carrier of capsaicin. S2, an ultrasonic-assisted extraction step; s3, a supercritical CO2 fluid extraction step; s4, a column chromatography separation and purification step; s5, composite auxiliary stabilization treatment; according to the preparation method, a process of combining ultrasonic-assisted extraction and supercritical CO2 fluid extraction is adopted, cell walls are effectively broken through an ultrasonic cavitation effect, active ingredients in the peppers are released more quickly, efficient dissolution is realized by utilizing high permeability of supercritical fluid, and a double-layer protection structure is formed after a microcapsule embedding technology is introduced, so that the stability of the peppers is improved. A barrier is physically formed, release of internal capsaicin is delayed, meanwhile, the response capacity of the system to the external environment is improved, and therefore intelligent controlled release in the in-vivo delivery process is achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of targeted food preparation, and specifically relates to the efficient preparation of capsaicin and the construction of its starch-based nanoparticle delivery carrier. Background Art

[0002] Chili is the second largest spice in the world after pepper, containing a variety of bioactive components with industrial uses such as capsaicinoids, phenolic compounds, carotenoids, and vitamins. It is an important source of new antibacterial compounds and antioxidants, and has good curative effects on anti-inflammatory analgesia, regulating glucose and lipid metabolism, anti-cancer, and anti-fatigue, with high industrial development and utilization value. The quantity of capsaicin and dihydrocapsaicin accounts for more than 80% of the total capsaicin. Capsaicin has antioxidant, anti-cancer, and anti-inflammatory properties. Its pyrogenic effect can become an important supplement for treating the current global obesity epidemic. Its antibacterial property can be used as a natural inhibitor of pathogenic microorganisms in food. In addition, capsaicin also has the potential to treat neurological diseases, including arthritis, cystitis, and human immunodeficiency virus (HIV). Chili is rich in phenolic compounds, mainly flavonoids, vanillin, caffeic acid, etc. Its medicinal properties include cancer prevention, arteriosclerosis prevention, and anti-inflammatory activity. Ripe chili is one of the most effective lipid peroxidation inhibitors, probably due to its relatively high content of phenolic substances and strong reducing power, playing an important role as a direct free radical scavenger. Chili is one of the richest sources of carotenoids, which affect the color and flavor of chili and play a role in preventing certain types of cancers, age-related macular degeneration, cataracts and other degenerative diseases. It can also act as an antioxidant to protect cells from free radical damage by reactive oxygen species (ROS) and delay the aging process. Chili is considered a good source of vitamin C, with a content 10 times that of tomatoes, playing a role in preventing scurvy, DNA mutations caused by oxidative stress, certain types of cancers, coronary heart disease, arteriosclerosis, cataracts, and kidney diseases. It also stimulates the immune system, inhibits the formation of nitrosamines, and blocks the metabolic activation of carcinogens. The components of vitamin E in chili, α-tocopherol and γ-tocopherol, are related to antioxidant effects, and their effectiveness is approximately 250 times that of the antioxidant BHT (butylated hydroxytoluene).

[0003] China is a major producer and consumer of chili. However, due to the limitations of traditional utilization methods, chili processing products mainly produce primary edible products such as chili sauce, chili oil, and chili chips through pickling, oil processing, and pickling methods. There is insufficient in-depth research on processing high-value-added fine products, and the development of medicinal value and functional characteristics still needs further study. Considering the benefits of capsaicin functional factors to human health and the food industry, exploring the active mechanism of capsaicin functional factors and applying them to improve food function and sensory quality is a very promising research field in terms of the behavior of consumers and the industry.

[0004] In view of this, the inventor proposes an efficient preparation of capsaicin and the construction of a starch-based nanoparticle delivery carrier to solve the above problems. Summary of the Invention

[0005] The purpose of the present invention is to provide an efficient preparation of capsaicin and the construction of a starch-based nanoparticle delivery carrier to solve the problems raised in the above background technology.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] An efficient preparation method of capsaicin, comprising the following steps:

[0008] S1. Pretreatment step: Pretreat the selected mature pepper raw materials with a relatively high capsaicin content to increase the specific surface area of the raw materials and obtain pretreated chili powder.

[0009] S2. Ultrasound-assisted extraction step: Mix the pretreated chili powder with an extraction solvent at a solid-liquid ratio of 1:10 to 1:20, place it in an ultrasonic reactor, and utilize the ultrasonic cavitation effect to promote the rupture of cell walls and the release of capsaicin to obtain a primary crude extract containing capsaicin.

[0010] S3. Supercritical CO2 fluid extraction step: Introduce the crude extract into a supercritical CO2 fluid extraction device for extraction to obtain a fluid extract.

[0011] S4. Column chromatography separation and purification step: Filter the fluid extract and send it into a column chromatography purification system for adsorption and elution treatment to obtain a high-purity natural capsaicin monomer or specific components.

[0012] S5. Composite auxiliary stabilization treatment: Blend the purified capsaicin with vitamin E at a concentration range of 0.01% to 0.05% and let it stand for 1 to 2 hours at 25 to 30 °C under an inert atmosphere to prevent the oxidation and decomposition of capsaicin during subsequent storage and application, and obtain a final stable natural capsaicin product.

[0013] Preferably, the pretreatment steps include cleaning, air drying or low-temperature drying, and mechanical crushing followed by screening to a range of 50 to 150 μm.

[0014] Preferably, the reaction conditions of the ultrasonic reactor are under the conditions of 40 to 50 °C, with an ultrasonic power of 200 to 500 W, and a treatment time of 20 to 40 minutes;

[0015] The extraction solvent is ethanol.

[0016] Preferably, the conditions for supercritical CO2 fluid extraction are as follows: at a pressure of 20 - 35 MPa and a temperature of 35 - 50 °C, the extraction time is set to 30 - 60 minutes, which is used to further extract capsaicin by utilizing the excellent permeability and solubility of supercritical CO2 to obtain a fluid extract.

[0017] Preferably, for the adsorption and elution treatment, macroporous resin or silica gel is used as the filler for adsorption. After adsorption, gradient ethanol elution is carried out within 30 - 60 minutes, where the ethanol concentration increases in a gradient of 40% - 80%, which is used to effectively separate and purify the molecular components of capsaicin to obtain high-purity natural capsaicin monomers or specific components.

[0018] A method for constructing a capsaicin starch-based nanoparticle delivery carrier includes the natural capsaicin product prepared by the above-mentioned method. The construction method includes the following steps:

[0019] A step for preparing modified starch: reacting food-grade natural starch with citric acid at 30 - 60 °C for 1 - 2 hours, and controlling the degree of modification at 30% - 70% after the reaction to obtain a modified starch solution; this is used to improve the embedding ability of starch molecules for hydrophobic capsaicin through partial acylation or cross-linking reactions to obtain a modified starch solution.

[0020] A step for pre-mixing capsaicin: mixing the natural capsaicin product and the modified starch solution according to a mass ratio of 1:10 - 1:20, and adding a surfactant at the same time to uniformly disperse the two phases to obtain a pre-mixed homogeneous solution, which provides a precursor system for self-assembly.

[0021] A step for nano self-assembly and precipitation: slowly adding the pre-mixed homogeneous solution to ethanol by dropping, and reacting under stirring conditions at a temperature of 25 - 35 °C and 300 - 500 rpm to obtain nanoparticles initially loaded with capsaicin; this is used to induce the self-assembly of modified starch and capsaicin under conditions of a sudden change in solvent polarity and form nanoparticles initially loaded with capsaicin.

[0022] A step for microemulsification and homogenization treatment: placing the nanoparticles initially loaded with capsaicin in an oil-water mixed system, controlling the oil-water phase ratio within the range of 1:4 - 1:8, and using a high-shear emulsification device or ultrasonic emulsification for 10 - 20 minutes of treatment, maintaining the temperature at room temperature to 35 °C to obtain a homogenized nanoparticle system; this is used to make the particle size distribution of the nanoparticles uniform and further enhance the embedding effect to obtain a homogenized nanoparticle system.

[0023] The microcapsule secondary embedding step: Mix the homogenized nanoparticle system with chitosan or protein solution, and carry out microcapsule embedding by the emulsification-curing or spray drying method under the conditions of pH value 4.0 - 6.0 and temperature 30 - 45 °C to form an external protective layer, ensuring the stable release of nanoparticles in complex in-vivo and in-vitro environments, and obtaining the final capsaicin-loaded starch-based nanoparticle delivery carrier;

[0024] Environmental response regulation treatment: Modify the surface of the obtained carrier with temperature- or pH-sensitive polymers, and control the reaction conditions at room temperature for 1 - 2 hours to enable the carrier to achieve intelligent controlled release in the simulated gastrointestinal environment, and obtain an intelligent delivery carrier with adjustable release characteristics.

[0025] Preferably, the surfactant is Tween-80 with a concentration of 0.05% - 0.2%.

[0026] Preferably, the temperature- or pH-sensitive polymer is poly(N-isopropylacrylamide) or gelatin.

[0027] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0028] (1) The present invention adopts a process combining ultrasonic-assisted extraction and supercritical CO2 fluid extraction. Through the ultrasonic cavitation effect, the cell wall is effectively broken, enabling the faster release of the active ingredients inside the chili, and the high permeability of the supercritical fluid is used to achieve efficient dissolution.

[0029] (2) In terms of carrier design, the present invention uses modified starch as the substrate, changes the hydrophilicity and hydrophobicity of starch through chemical modification, and increases the interaction between starch and hydrophobic capsaicin molecules, thus facilitating the efficient embedding of capsaicin. The self-assembly process is carried out in a non-solvent environment. Through the induction of self-assembly and precipitation reactions between modified starch and capsaicin, a tightly structured nanoparticle structure is formed. Furthermore, microemulsification and high-shear treatment make the particle size distribution more uniform, ensuring that the drug carrier has good physical stability and biocompatibility.

[0030] (3) After introducing the microcapsule embedding technology, the present invention forms a double-layer protection structure, which not only physically forms a barrier to delay the release of internal capsaicin, but also increases the response ability of the system to the external environment (such as pH and temperature changes), thereby achieving intelligent controlled release during in-vivo delivery. This delivery system can effectively control the release rate of capsaicin in different digestive environments, reduce the initial rapid release or "burst effect", and achieve the goal of prolonging the drug effect and improving the bioavailability. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a flow chart of the high-efficiency preparation method of capsaicin of the present invention;

[0032] Figure 2 Flow chart of the construction method of the capsaicin starch-based nanoparticle delivery carrier of the present invention. Specific implementation manners

[0033] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0034] Example 1:

[0035] As Figures 1 to 2 shown, application examples and comparative tests of the high-efficiency preparation method of capsaicin:

[0036] I. Experimental purpose:

[0037] Verify the improvement effect of the "ultrasound + supercritical CO2 + column chromatography" combined process in the present solution compared with the traditional "ethanol reflux extraction method" in terms of capsaicin extraction efficiency and purity.

[0038] II. Experimental materials and equipment parameters are as shown in Table 1 below:

[0039] Table 1 Experimental materials and equipment parameters

[0040]

[0041] III. Experimental process:

[0042] 1. Experimental group (the present invention solution is as shown in Table 2 below):

[0043] Table 2 Explanation of the experimental group

[0044]

[0045] 2. Control group (traditional method, parameters are as shown in Table 3 below):

[0046] Table 3 Explanation of the control group

[0047]

[0048] IV. Detection and comparison results are as shown in Table 4 below:

[0049] Table 4 Comparison of results between the experimental group and the control group

[0050]

[0051]

[0052] Description of detection means:

[0053] Extraction rate: Based on dried chili powder, it is converted after measuring the capsaicin content by HPLC.

[0054] Purity: Use HPLC integration method to analyze the monomer peak area ratio.

[0055] Solvent consumption: Record the volume of ethanol consumed in a single batch experiment, and calculate the volume corresponding to the unit dry powder mass.

[0056] As can be seen from the above, the composite extraction process proposed by the present invention has significant advantages over the traditional method in terms of extraction efficiency, purification quality, resource consumption and time cost, etc., and is especially suitable for industrial large-scale extraction;

[0057] Adopt the process of combining ultrasonic-assisted extraction and supercritical CO2 fluid extraction. Through the ultrasonic cavitation effect, the cell wall is effectively broken, so that the active ingredients inside the chili are released faster, and the high permeability of the supercritical fluid is used to achieve efficient dissolution. This combined process enables a large amount of active ingredients to be extracted under mild conditions, while avoiding the thermal degradation problem caused by high temperature and long-time treatment. Column chromatography further realizes the highly purification of the target component by finely controlling the adsorption and elution conditions, thereby ensuring that the extract has high activity and stability. In theory, this multi-step composite process not only improves the single extraction efficiency, but also ensures the integrity of the capsaicin molecular structure in the extract, avoiding the decline of purity and activity brought by traditional single extraction technology.

[0058] Example 2:

[0059] Construction of capsaicin starch-based nanoparticle delivery carrier and comparison of controlled release performance:

[0060] I. Experimental purpose:

[0061] Through the encapsulation experiment of capsaicin, verify the advantages of the controlled release system using "modified starch + self-assembled nano-precipitation + microcapsule encapsulation" in terms of encapsulation rate, particle size uniformity, in vitro release control ability and improvement of bioavailability.

[0062] II. Experimental materials and equipment, the parameters are shown in Table 5 below:

[0063] Table 5 Experimental materials and equipment

[0064]

[0065] III. Experimental group design:

[0066] 1. Implementation group, the parameters are shown in Table 6, Table 7, Table 8 and Table 9 below:

[0067] Table 6 Description of the implementation group

[0068]

[0069] 2. Control group:

[0070] Use unmodified starch, without microcapsule treatment, and prepare nanoparticles only by simple emulsification method.

[0071] IV. Detection items and results are shown in Table 7 below:

[0072] Table 7 Comparison of physical parameters of carriers

[0073]

[0074] Table 8 Comparison of encapsulation efficiency and release performance

[0075]

[0076] Table 9 In vitro simulated absorption test (Caco-2 cell model)

[0077]

[0078] Detection instructions:

[0079] Particle size, PDI, Zeta potential: Measured using a Malvern laser particle size analyzer.

[0080] Encapsulation rate: Quantitative analysis of free and total capsaicin was carried out by HPLC.

[0081] Release test: Analyze the release curve under the continuous conversion conditions of in vitro simulated gastric juice (pH 1.2) → intestinal juice (pH 6.8).

[0082] Caco-2 cells: Detect the permeability of capsaicin in the cell monolayer model.

[0083] V. Technical effects and advantages description:

[0084] The particle size is smaller and the distribution is more uniform, indicating the success of the system self-assembly and emulsification process;

[0085] The encapsulation rate is increased by 63.5%, indicating that the double-layer structure formed by modified starch and chitosan has a stronger protective effect on hydrophobic active substances;

[0086] The experimental group showed obvious controlled release behavior in simulated in vitro digestion and had strong pH responsiveness;

[0087] In vitro cell experiments verified that the nano-delivery system significantly improved the absorption efficiency of capsaicin nearly twice.

[0088] As can be seen from the above, the comparison between the two above-mentioned embodiments and detailed data clearly demonstrates the technological advancement and practical feasibility of the present invention in the preparation and delivery of capsaicin. Through the integration of the technological process and innovation in carrier design, the problems existing in the traditional methods, such as low extraction efficiency, low purity, and unstable delivery, are effectively solved, providing a solid technical support for the development of functional foods and precision nutritional preparations;

[0089] In terms of carrier design, modified starch is used as the substrate, and the hydrophilicity and hydrophobicity of starch are changed through chemical modification to increase the interaction between it and hydrophobic capsaicin molecules, thus facilitating the efficient encapsulation of capsaicin. The self-assembly process is carried out in a non-solvent environment, and the self-assembly and precipitation reaction between the modified starch and capsaicin are induced to form a tightly structured nanoparticle structure. Furthermore, microemulsification and high-shear treatment make the particle size distribution more uniform, ensuring that the drug carrier has good physical stability and biocompatibility. After introducing the microcapsule encapsulation technology, a double-layer protection structure is formed, which not only forms a physical barrier to delay the release of internal capsaicin, but also increases the response ability of the system to the external environment (such as pH and temperature changes), thereby achieving intelligent controlled release during in vivo delivery. This delivery system can effectively control the release rate of capsaicin in different digestive environments, reduce the initial rapid release or "burst effect", so as to achieve the goal of prolonging the drug effect and improving the bioavailability;

[0090] This method combines the design concepts of physical and chemical stability. Through a series of environmentally responsive regulation treatments, the system has a high anti-interference ability when facing a complex in vivo environment (including the action of gastric acid, bile, and intestinal enzymes), can maintain the integrity of the delivery system structure at key sites, and achieve continuous drug release at the target site. At the same time, the use of mild process parameters ensures that the activity of capsaicin is not damaged during the whole preparation process. The strict control of conditions such as temperature, pressure, pH, and stirring rate during the system construction process ensures the controllability and reproducibility of the process, thus having good prospects for industrial promotion.

[0091] In the description of this specification, the description referring to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0092] In the accompanying drawings of the disclosed embodiments of the present invention, only the structures related to the disclosed embodiments are involved. For other structures, reference may be made to the usual designs. Without conflict, the same embodiment and different embodiments of the present invention may be combined with each other.

[0093] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art will understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An efficient method for preparing capsaicin, characterized in that: The following steps are involved: S1, pre-treating a selected mature pepper raw material containing a high capsaicin content to obtain pre-treated chili powder; S2, mixing the pretreated chili powder with the extraction solvent at a solid-liquid ratio of 1:10 to 1:20, placing the mixture in an ultrasonic reactor, and utilizing ultrasonic cavitation effect to promote cell wall rupture and release of capsaicinoids to obtain a primary capsaicinoid-containing crude extract; S3, introducing the primary capsaicinoid-containing crude extract into a supercritical CO2 fluid extraction device for extraction to obtain a fluid extract; S4, filtering the fluid extract and then sending it to a column chromatography purification system for adsorption and elution treatment to obtain high-purity natural capsaicin monomer or specific component; S5. The purified capsaicin is mixed with vitamin E at a concentration range of 0.01% to 0.05%, and the mixture is allowed to stand at 25 to 30° C. under an inert atmosphere for 1 to 2 hours to obtain a final stable natural capsaicin product.

2. The method for efficiently preparing capsaicin according to claim 1, wherein The pretreatment steps include cleaning, air drying or low-temperature drying, and mechanical crushing followed by screening to a size range of 50 to 150 μm.

3. The method for efficiently preparing capsaicin according to claim 1, wherein The reaction conditions of the ultrasonic reactor are 40-50°C, 200-500W ultrasonic power, and 20-40 minutes of treatment time; The extraction solvent is ethanol.

4. The method for efficiently preparing capsaicin according to claim 1, wherein The supercritical CO2 fluid extraction conditions are: under the conditions of 20-35 MPa pressure and 35-50°C temperature, the extraction time is set to 30-60 minutes, which is used to further extract capsaicin using the excellent permeability and solubility of supercritical CO2 to obtain a fluid extract.

5. The method for efficiently preparing capsaicin according to claim 1, wherein The adsorption and elution process uses macroporous resin or silica gel as filler for adsorption. After the adsorption is completed, gradient ethanol elution is used 30 to 60 minutes after adsorption, wherein the ethanol concentration increases gradually from 40% to 80%, so as to achieve effective separation and purification of capsaicin molecular components and obtain high-purity natural capsaicin monomers or specific components.

6. A method for constructing a capsaicin starch-based nanoparticle delivery carrier, characterized in that: The natural capsaicin product prepared by the method according to any one of claims 1 to 5, wherein the construction method comprises the following steps: The food-grade natural starch is reacted with citric acid at 30-60°C for 1-2 hours, and the degree of modification is controlled to be 30%-70% after the reaction to obtain a modified starch solution; The natural capsaicin product and the modified starch solution are mixed in a mass ratio of 1:10 to 1:20, and a surfactant is added to uniformly disperse the two phases to obtain a premixed homogeneous solution, which provides a precursor system for self-assembly; The premixed homogeneous solution is slowly added dropwise to ethanol, and the reaction is carried out at a temperature of 25 to 35° C. and a stirring speed of 300 to 500 rpm to obtain nanoparticles preliminarily loaded with capsaicin; placing the nanoparticles initially loaded with capsaicin in an oil-water mixture system, controlling the oil-water ratio within a range of 1:4 to 1:8, and treating the mixture for 10 to 20 minutes using a high shear emulsification device or ultrasonic emulsification, while maintaining the temperature at room temperature to 35° C., to obtain a homogenized nanoparticle system; The homogenized nanoparticle system is mixed with chitosan or protein solution, and microencapsulated by emulsification-solidification or spray drying at a pH of 4.0 to 6.0 and a temperature of 30 to 45° C. to form an outer protective layer, thereby obtaining a final capsaicin-loaded starch-based nanoparticle delivery carrier; The surface of the obtained carrier is modified with a temperature- or pH-sensitive polymer, and the reaction conditions are controlled at room temperature for 1 to 2 hours to enable the carrier to achieve intelligent controlled release in a simulated gastrointestinal environment, thereby obtaining an intelligent delivery carrier with adjustable release characteristics.

7. The method for constructing a capsaicin starch-based nanoparticle delivery carrier according to claim 6, characterized in that: The surfactant is Tween-80 with a concentration of 0.05% to 0.2%.

8. The method for constructing a capsaicin starch-based nanoparticle delivery carrier according to claim 6, characterized in that: The temperature- or pH-sensitive polymer is poly(N-isopropylacrylamide) or gelatin.

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