A superamphiphile-based high-performance curcumin carrier based on modular construction, and a preparation method and application thereof

Abstract

The application discloses a kind of super amphiphilic molecule based high-performance curcumin carrier based on modular construction and its preparation method and application, belong to biotechnology field.The preparation method in which β-cyclodextrin is encapsulated curcumin by host-guest interaction, sodium caseinate is treated by alkali to expose hydrophobic group and mix with inclusion complex, resulting in the rigid macrocycle of inclusion complex and the flexible open chain of alkali-treated sodium caseinate are combined by non-covalent interaction to form super amphiphilic molecule, then part of curcumin is added to interact with uncombined hydrophobic sites, after stirring and ultrasonic, use citric acid to adjust back to neutral induction system to assemble into nanoparticles, add maltodextrin and process by stirring, centrifugation, spray drying etc.The curcumin carrier prepared by the application has excellent water solubility, high stability, good powder physical properties, high bioavailability, simple process production, and has great commercial value.

Description

Technical Field

[0001] This invention belongs to the field of biotechnology, specifically relating to a high-performance curcumin support based on a modularly constructed amphiphilic molecular base, its preparation method, and its application. Background Technology

[0002] Curcumin, the main active ingredient in turmeric, is chemically named 1,7-bis(4-hydroxy-3-methoxyphenyl)-1,6-diene-3,5-heptadecane or diferoylmethane. It is a rare pigment in the plant kingdom containing a β-diketone structure and has great potential applications in food and pharmaceuticals. In the food industry, curcumin is a common flavoring agent, providing flavor to curry; it is also used as a coloring agent in colored chocolate, ice cream, and beverages. Due to its numerous physiological activities, such as excellent antioxidant, antibacterial, anti-inflammatory, antitumor, lipid-lowering, anticoagulant, antithrombotic, immune-regulating, anti-immunodeficiency virus, and hypoglycemic effects, curcumin has been widely used in health foods and pharmaceuticals, including as a hangover remedy, anti-inflammatory drug, and in cancer clinical treatment. However, curcumin's low bioavailability, poor photothermal stability, and low water solubility increase the difficulty of its further processing. This means that curcumin needs to be introduced into the food industry through a specially designed, stable, hydrophilic delivery system. However, many hydrocolloid materials are expensive to manufacture, have low encapsulation and loading efficiency, pose certain food safety risks, and are limited to small-scale production. Their low resolubility and poor stability also restrict the application of curcumin to the industrial and commercial levels.

[0003] Superamphiphilic molecules are structures with controllable properties and advanced functions formed by designing the position, volume, or length of sub-components of amphiphilic molecules, such as hydrophobic tails, and then further polymerizing them. Based on modular construction, loosely structured proteins such as sodium caseinate and cyclodextrin-curcumin inclusion complexes with rigid macrocycles were constructed using pH-driven and ultrasonic methods, respectively. The flexible open chain of sodium caseinate assembles into a special structured superamphiphilic molecule through non-covalent interactions between the flexible open chain of sodium caseinate and the rigid macrocycle of cyclodextrin. This provides multiple binding sites for hydrophobic bioactive substances such as curcumin, resulting in a significant loading potential for these substances. Specifically, the flexible open chain of the hydrophilic layer of sodium caseinate interacts supramolecularly with molecules such as cyclodextrin, which have a hydrophilic surface and a hydrophobic interior, and possess rigid macrocycles. This allows curcumin, encapsulated by cyclodextrin, to enter the hydrophilic layer region of sodium caseinate, significantly increasing the molecular space utilization for curcumin binding. This leads to a significantly higher curcumin loading effect in supramolecular self-assembled nanoparticles compared to conventional nanoparticles. In addition, this unique superamphilic molecular structure endows the encapsulated curcumin with good water solubility and stability, solving the current production problems of curcumin-based foods.

[0004] Patent document CN 115607524 B, entitled "A Curcumin-Loaded Composite Nanoparticle and Its Preparation Method," discloses a method for preparing zein-carboxymethyl poria cocos polysaccharide composite particles loaded with curcumin. This method is simple to operate, low in cost, and produces particles with excellent properties. However, the method uses toxic organic reagents such as isopropanol and monochloroacetic acid, posing a food safety risk and thus limiting its application in food.

[0005] Patent document CN 113730373 B, entitled "A zein-AOS composite nanoparticle for delivering curcumin and its preparation method", discloses a zein-alginate oligosaccharide composite nanoparticle with high encapsulation efficiency and high thermal stability. However, it is unstable under strong acid conditions (pH=3), with a particle size of 1424.3 nm, a PDI of 0.47, and severe aggregation, which limits its application in acidic foods.

[0006] Patent document CN 115105486 A, entitled "A self-assembled nanoparticle of soy protein isolate-curcumin stabilized by a dianionopolysaccharide and its preparation method," discloses a self-assembled nanoparticle of soy protein isolate-curcumin stabilized by a dianionopolysaccharide and its preparation method. The composite self-assembled nanoparticles are prepared using fucoidan / carrageenan / soy protein isolate / curcumin and have good stability parameters. However, the particle size is about 620 nm, which is relatively large. This may make it difficult for the nanoparticles to penetrate the cell mucus layer during in vivo absorption, affecting the bioavailability of curcumin. In addition, the system has high turbidity, which may reduce consumers' purchasing desire when it is used as a commercial product, making it difficult for the system to have high commercial competitiveness.

[0007] The article "Fabrication of curcumin-loaded bovine serum albumin (BSA)-dextran nanoparticles and the cellular antioxidant activity" encapsulates curcumin with a glycosylated conjugate prepared from bovine serum albumin and dextran, resulting in curcumin nanoparticles with lower average particle size, higher antioxidant activity, and greater stability. Although their thermal stability is improved compared to free curcumin, their curcumin retention rate is still only 30.3%, which may lead to a significant decrease in curcumin content during industrial heat sterilization.

[0008] The article "A new green self-assembly strategy for preparing curcumin-loaded starch nanoparticles based on natural deep eutectic solvent: Development, characterization and stability" uses the deep eutectic solvent method to prepare starch nanoparticles and encapsulate curcumin. This method is green and environmentally friendly and the preparation method is simple, but its maximum curcumin loading rate is only 7.99 mg / g, which greatly limits the application of curcumin in commercial and food industries. Therefore, improving the curcumin loading rate is an extremely critical issue.

[0009] The article "Fabrication and characterization of curcumin-loaded liposomes formed from sunflower lecithin: Impact of composition and environmental stress" describes the fabrication of curcumin liposomes using microfluidic technology. The curcumin encapsulated in these liposomes tends to crystallize at room temperature, and the stacking of the phospholipid bilayer is disrupted by curcumin, leading to structural damage. These factors limit the development of curcumin liposomes into industrially scalable curcumin nanoparticles.

[0010] Therefore, creating high-performance and industrially viable curcumin nanoparticles is a key challenge that engineers urgently need to overcome. Currently, there are no reports of nanoparticles mediated by supra-amphiphilic molecules loaded with curcumin. These uniquely structured nanoparticles can endow curcumin with good stability, water solubility, and bioavailability, as well as good powder physical properties, high curcumin loading capacity, low cost, and ease of large-scale production. Summary of the Invention

[0011] To address the current technical limitations on the application of curcumin, this invention provides a high-performance water-soluble curcumin powder and its preparation method by using a superamphilic molecular loading curcumin obtained through the flexible opening of the hydrophilic layer of casein and the rigid macrocycle self-assembly of β-cyclodextrin.

[0012] Firstly, the innovation of this invention lies in providing a high-performance active substance support based on a modularly constructed amphiphilic molecular base, comprising β-cyclodextrin, alkali-treated sodium caseinate, and an active substance. Furthermore, the active substance is a hydrophobic bioactive substance. Research has shown that the hydrophobic bioactive substance can be treated with β-cyclodextrin and alkali-treated sodium caseinate to obtain a high-performance water-soluble active substance support.

[0013] Furthermore, this invention specifically uses curcumin as the research object to prepare curcumin supports and studies their specific preparation process and performance. This invention involves encapsulating curcumin with β-cyclodextrin through host-guest interactions. Sodium caseinate is treated with alkali to expose hydrophobic groups, which are then mixed with the inclusion complex. The rigid macrocycle of the inclusion complex and the flexible open chain of the alkali-treated sodium caseinate bind through non-covalent interactions to form a supraamophilic molecule. Then, some curcumin is added to interact with the unbound hydrophobic sites. After stirring and sonication, the mixture is adjusted back to neutral with citric acid to induce the assembly into nanoparticles. Maltodextrin is added, and the mixture is then stirred, centrifuged, and spray-dried to obtain the final product.

[0014] The preparation of this invention is achieved through the following technical solution:

[0015] (1) Dissolve curcumin completely in ethanol solution to obtain solution A. Add β-cyclodextrin to deionized water and stir until completely dissolved to obtain solution B. Slowly add solution A dropwise to solution B and stir at 60°C until the ethanol is completely evaporated and the liquid color is uniform after sonication to obtain solution C.

[0016] (2) Sodium caseinate was completely dissolved in deionized water and hydrated overnight. The pH was then adjusted to alkaline to obtain solution D. Curcumin was completely dissolved in solution D. Solution C was added to solution D and the pH was adjusted to keep it alkaline. After sonication, the solution was stirred until the liquid color was uniform to obtain solution E.

[0017] (3) Adjust the pH of solution E to neutral, stir until the liquid color is uniform, centrifuge and obtain the supernatant to obtain solution F;

[0018] (4) Add the maltodextrin to the continuously stirred liquid F until the system is homogeneous;

[0019] (5) The above homogeneous system is spray-dried to obtain a high-performance curcumin support based on a modularly constructed amphiphilic molecular base.

[0020] Preferably, the mass ratio of β-cyclodextrin to curcumin in step (1) is (1.6~4.4):1.

[0021] Preferably, in step (1), the ultrasonic cell disruptor is used to sonicate the cells at 800 W for 5-10 minutes.

[0022] Preferably, in step (2), the pH of the alkaline solution obtained by adjusting the pH using food-grade sodium hydroxide is between 11.0 and 12.0.

[0023] Preferably, the mass ratio of sodium caseinate to curcumin in step (2) is (1.6~4.4):1.

[0024] Preferably, the mass ratio of sodium caseinate to cyclodextrin in step (2) is (0.6~3):1.

[0025] Preferably, the solution is stirred at a speed of 500 rpm for 1 h in step (2).

[0026] Preferably, step (2) involves using an ultrasonic cell disruptor to sonicate at 800 W for 5-10 minutes.

[0027] Preferably, step (3) involves adjusting the pH using citric acid to a pH of 6.5 to 7.0.

[0028] Preferably, the solution is stirred at a speed of 500 rpm for 3 hours in step (3).

[0029] Preferably, the mass ratio of maltodextrin to sodium caseinate in step (4) is (0~5):1.

[0030] Preferably, the inlet air temperature of the spray dryer in step (5) is 150 °C, the outlet air temperature is 200 °C, and the feed rate is 7~10 rpm.

[0031] This invention provides a high-performance curcumin support based on a modularly constructed superamphilic molecular base, which is prepared by the above method.

[0032] Compared with existing curcumin encapsulation technology, the beneficial effects and advantages of the present invention are as follows:

[0033] (1) The raw material sodium caseinate selected in this invention is an edible product obtained by acidification, neutralization and drying of casein. It has high thermal stability, good resolubility, large industrial output and low price, and has high nutritional value. β-Cyclodextrin is a food additive that is allowed to be added by food standards and regulations. It has good light stability and resolubility and is easily soluble in water. This invention can broaden the path for the deep processing of sodium caseinate and β-cyclodextrin.

[0034] (2) The high-performance curcumin support based on modular construction of superamphilic molecular base prepared by the present invention has excellent photostability, thermal stability and sugar-acid stability. That is, the support can maintain a high curcumin retention rate during industrial production and is suitable for use in sugar-acid foods, thus broadening the industrial and commercial application scope of the support.

[0035] (3) The high-performance curcumin support based on modular construction of superamphilic molecular base prepared by the present invention not only greatly improves the water solubility of curcumin, but also the spray-dried powder of the support exhibits excellent powder physical properties, which is suitable for industrial powder storage and transportation and has high commercial competitiveness.

[0036] (4) The superamphilic molecules assembled by the flexible open chain of sodium caseinate and the rigid macrocycle of β-cyclodextrin through non-covalent interactions of the present invention, after loading curcumin, have a small average particle size. During in vivo digestion and absorption, they are easily micellized and can more easily pass through the mucus layer of cells, resulting in a higher proportion of loaded curcumin being digested and absorbed in vivo. After testing, the powder loading rate can reach up to 13.40%, and the average particle size can reach as low as 142.4 nm. The spray-dried powder can be completely reconstituted within 5 min without any agglomeration, adhesion to the wall, precipitation or other adverse phenomena. After treatment with D65 natural light for 120 h, the curcumin retention rate can reach up to 61.74%. After heating treatment at 95 °C for 120 min, the curcumin retention rate can reach up to 78.01%, and the average particle size does not increase significantly. After sugar acid treatment (pH=3), the curcumin retention rate can reach up to 92.98%, and the average particle size does not increase significantly.

[0037] (5) The raw materials used in this invention are all non-toxic and harmless food-grade raw materials, do not contain synthetic emulsifiers, and the manufacturing process is simple and low-cost, making it suitable for large-scale industrial production. Attached Figure Description

[0038] Figure 1 The Fourier transform infrared spectra of sodium caseinate, β-cyclodextrin, sodium caseinate-β-cyclodextrin complex, curcumin, and Examples 4-5 are shown.

[0039] Figure 2 The UV spectra of sodium caseinate, β-cyclodextrin, maltodextrin, curcumin, and Examples 4-5 are shown.

[0040] Figure 3 The fluorescence spectrum of sodium caseinate during the pH-driven process is shown.

[0041] Figure 4 The images show transmission electron microscopy results for sodium caseinate, β-cyclodextrin, and Examples 4-5.

[0042] Figure 5 These are atomic force microscopy images of sodium caseinate, β-cyclodextrin, and Examples 4-5.

[0043] Figure 6 The encapsulation efficiency and loading rate of the water-soluble curcumin powder in Examples 1-5 are given.

[0044] Figure 7 The average particle size and zeta potential of the water-soluble curcumin powder in Examples 1-5 are given.

[0045] Figure 8 The images show the front and top views of the water-soluble powders prepared in Examples 4-5 and their water resolution.

[0046] Figure 9 The curcumin retention rate after heat treatment following reconstitution of the water-soluble curcumin powder obtained in Examples 4-5.

[0047] Figure 10 The change in average particle size of the water-soluble curcumin powder obtained in Examples 4-5 after heat treatment following reconstitution.

[0048] Figure 11 The curcumin retention rate after light treatment following reconstitution of the water-soluble curcumin powder obtained in Examples 4-5. Detailed Implementation

[0049] The following examples further illustrate the specific implementation of the present invention, but the implementation and protection scope of the present invention are not limited thereto.

[0050] Unless otherwise specified, the experimental methods used in this embodiment are conventional methods; and the materials and reagents used (sodium caseinate, β-cyclodextrin, maltodextrin, curcumin, etc.) are commercially available unless otherwise specified.

[0051] Example 1:

[0052] β-Cyclodextrin (1200 mg) was added to ultrapure water (100 mL) and stirred continuously at 900 rpm for 60 minutes at 60 °C. Curcumin (250 mg) dissolved in 30 mL of ethanol was added dropwise to the β-cyclodextrin dispersion. The mixture was stirred at 900 rpm at 60 °C while keeping the lid open to evaporate the ethanol. After the ethanol had completely evaporated, the lid was closed to prevent water evaporation. The stirring was carried out for a total of 20 h. The mixture was then sonicated using an ultrasonic cell disruptor to obtain a β-cyclodextrin inclusion complex suspension.

[0053] 400 mg of sodium caseinate was dissolved in 100 mL of deionized water and stirred at 400 rpm for 1 h on a magnetic stirring plate. The solution was then hydrated at room temperature for at least 6 hours, and the pH was adjusted to 12 using food-grade NaOH solution. 250 mg of curcumin powder and 100 mL of β-cyclodextrin inclusion complex suspension were added to the sodium caseinate solution. The mixture was sonicated and stirred (500 rpm, 1 h). The mixture was then acidified to pH 7 with citric acid and stirred (500 rpm, 3 h) to obtain a composite system, which was then centrifuged (10000 rpm, 10 min). The centrifuged composite system solution was then spray-dried at an inlet air temperature of 150°C, an outlet air temperature of 200°C, and a feed rate of 10 rpm to obtain water-soluble curcumin powder.

[0054] Example 2:

[0055] β-Cyclodextrin (1000 mg) was added to ultrapure water (100 mL) and stirred continuously at 900 rpm for 60 minutes at 60 °C. Curcumin (250 mg) dissolved in 30 mL of ethanol was added dropwise to the β-cyclodextrin dispersion. The mixture was stirred at 900 rpm at 60 °C while keeping the lid open to evaporate the ethanol. After the ethanol had completely evaporated, the lid was closed to prevent water evaporation. The stirring was carried out for a total of 20 h. The mixture was then sonicated using an ultrasonic cell disruptor to obtain a β-cyclodextrin inclusion complex suspension.

[0056] 600 mg of sodium caseinate was dissolved in 100 mL of deionized water and stirred at 400 rpm for 1 h on a magnetic stirring plate. The solution was then hydrated at room temperature for at least 6 hours, and the pH was adjusted to 12 using food-grade NaOH solution. 250 mg of curcumin powder and 100 mL of a β-cyclodextrin inclusion complex suspension were added to the sodium caseinate solution. The mixture was sonicated and stirred (500 rpm, 1 h). The mixture was then acidified to pH 7 with citric acid and stirred (500 rpm, 3 h) to obtain a composite system, which was then centrifuged (10000 rpm, 10 min). The centrifuged composite system solution was then spray-dried at an inlet air temperature of 150°C, an outlet air temperature of 200°C, and a feed rate of 10 rpm to obtain water-soluble curcumin powder.

[0057] Example 3:

[0058] Add β-cyclodextrin (400 mg) to ultrapure water (100 mL) and stir continuously at 900 rpm for 60 minutes at 60 °C. Add curcumin (250 mg) dissolved in 30 mL of ethanol dropwise to the β-cyclodextrin dispersion. Stir the mixture at 900 rpm at 60 °C and keep the lid open to evaporate the ethanol. After the ethanol has completely evaporated, close the lid to prevent water evaporation. Stirring is carried out for a total of 20 h. Use an ultrasonic cell disruptor to sonicate and obtain a β-cyclodextrin inclusion complex suspension.

[0059] 1200 mg of sodium caseinate was dissolved in 100 mL of deionized water and stirred at 400 rpm for 1 h on a magnetic stirring plate. The solution was then hydrated at room temperature for at least 6 hours, and the pH was adjusted to 11.5 using food-grade NaOH solution. 250 mg of curcumin powder and 100 mL of a β-cyclodextrin inclusion complex suspension were added to the sodium caseinate solution. The mixture was sonicated and stirred (500 rpm, 1 h). The mixture was then acidified to pH 6.5 with citric acid and stirred (500 rpm, 3 h) to obtain a composite system, which was then centrifuged (10000 rpm, 10 min). The centrifuged composite system solution was then spray-dried at an inlet air temperature of 150°C, an outlet air temperature of 200°C, and a feed rate of 10 rpm to obtain water-soluble curcumin powder.

[0060] Example 4:

[0061] Add β-cyclodextrin (3 g) to ultrapure water (500 mL) and stir continuously at 900 rpm for 60 minutes at 60 °C. Add curcumin (1.25 g) dissolved in 130 mL of ethanol dropwise to the β-cyclodextrin dispersion. Stir the mixture at 900 rpm at 60 °C and keep the lid open to evaporate the ethanol. After the ethanol has completely evaporated, close the lid to prevent water evaporation. Stirring is carried out for a total of 20 h. Use an ultrasonic cell disruptor to sonicate and obtain a β-cyclodextrin inclusion complex suspension.

[0062] 5 g of sodium caseinate was dissolved in 500 mL of deionized water and stirred at 400 rpm for 1 h on a magnetic stirring plate. The solution was then hydrated at room temperature for at least 6 hours, and the pH was adjusted to 12 using food-grade NaOH solution. 1.25 g of curcumin powder and 500 mL of β-cyclodextrin inclusion complex suspension were added to the sodium caseinate solution. The mixture was sonicated and stirred (500 rpm, 1 h). The mixture was then acidified to pH 7 with citric acid and stirred (500 rpm, 3 h) to obtain a composite system. The system was centrifuged (10000 rpm, 10 min). The centrifuged composite system solution was then spray-dried at an inlet air temperature of 150°C, an outlet air temperature of 200°C, and a feed rate of 7 rpm to obtain water-soluble curcumin powder.

[0063] Example 5:

[0064] Following the process described in Example 4, and with the addition of maltodextrin, an experiment was conducted to prepare water-soluble curcumin powder. The preparation process is as follows:

[0065] β-cyclodextrin (2625 mg) was added to ultrapure water (400 mL) and stirred continuously at 900 rpm for 60 minutes at 60 °C to prepare a β-cyclodextrin stock solution. 4375 mg of sodium caseinate was dissolved in 400 mL of deionized water and stirred at 400 rpm for 1 h on a magnetic stirring plate. After hydration at room temperature for more than 6 hours, a sodium caseinate stock solution was prepared.

[0066] Curcumin (850 mg) dissolved in 90 ml ethanol was added dropwise to 400 ml of β-cyclodextrin stock solution. The mixture was stirred at 900 rpm for 20 h at 60 °C with the cap open to allow ethanol to evaporate. The mixture was then sonicated to obtain a cyclodextrin inclusion complex suspension. The pH of 400 ml sodium caseinate stock solution was adjusted to 12 using food-grade NaOH solution and stirred for 30 min. Then, 1.1 g of curcumin powder was added to sodium caseinate and completely dissolved. The β-cyclodextrin inclusion complex suspension was then added separately and stirred (500 rpm, 30 min). The mixture was then sonicated for 5 min using an ultrasonic cell disruptor to ensure the loose sodium caseinate was fully combined with β-cyclodextrin and curcumin under alkaline conditions. The mixture was acidified to pH 7 with citric acid and stirred (500 rpm, 3 h). The mixture was centrifuged (10000 rpm, 10 min) to obtain the supernatant. The centrifuged composite solution was then stirred under stirring conditions (500 rpm, 30 min). 1050 mg of maltodextrin was gradually added (min) and mixed thoroughly to obtain a composite system for spray drying. The inlet air temperature of the spray dryer was 150 °C, the outlet air temperature was 200 °C, and the feed rate was 7 rpm, to obtain water-soluble curcumin powder.

[0067] Experimental Example 1: Fourier Transform Infrared Spectroscopy

[0068] Using water-soluble curcumin powder, sodium caseinate powder, β-cyclodextrin powder, sodium caseinate-β-cyclodextrin complex powder, and curcumin powder prepared in Examples 4-5 as experimental samples, Fourier transform infrared spectroscopy was performed. Dry, spectrally pure potassium bromide powder was mixed uniformly with a small amount of the sample to be analyzed at a mass ratio of 50:1 in an agate mortar, and the mixture was pressed into tablets. The readings were recorded at 500-4000 cm⁻¹. -1 The infrared spectrum was scanned at a resolution of 4 cm⁻¹. -1 The test temperature was maintained at 25 ℃. The infrared spectroscopy test results show that 3504 cm⁻¹ did not appear in the spectra of Examples 4 and 5. -1 The peak (characteristic peak of curcumin) is not the same as the peak at 3308 cm⁻¹. -1The peak merging proves that curcumin interacts with the wall material of the system, rather than a simple physical mixing; the characteristic peak of sodium caseinate at 3296 cm⁻¹ is obtained from the infrared spectra of the sodium caseinate-β-cyclodextrin complex and β-cyclodextrin. -1 Shifting to higher wavenumbers to 3311 cm -1 The characteristic peak of Example 4 is 3308 cm⁻¹. -1 After secondary microencapsulation with maltodextrin, it migrates to a higher wavelength of 3324 cm⁻¹. -1 This demonstrates that maltodextrin interacts with the powder of Example 4 and is successfully microencapsulated on the surface a second time; Fourier transform infrared spectroscopy clearly demonstrates that there is an interaction between sodium caseinate, curcumin, maltodextrin, and β-cyclodextrin.

[0069] Experimental Example 2: Ultraviolet Spectroscopy

[0070] Using water-soluble curcumin powder, sodium caseinate powder, β-cyclodextrin powder, curcumin powder, and maltodextrin powder prepared in Examples 4-5 as experimental samples, ultraviolet spectroscopy was performed, and the ultraviolet absorption spectra in the wavelength range of 200~600 nm were recorded. The results of the ultraviolet spectroscopy test show that the characteristic absorption peak in Example 4 is about 404 nm, which is slightly blue-shifted compared to the characteristic absorption peak of free curcumin (426 nm). This can prove to some extent that the sodium caseinate-cyclodextrin complex interacts with curcumin, rather than being a simple physical mixture. Compared with Example 4, the ultraviolet absorption characteristic peak of Example 5 is slightly blue-shifted from 405 nm to 403 nm, indicating that maltodextrin interacts with the curcumin support in Example 4 and is successfully microencapsulated on the surface of the support.

[0071] Experimental Example 3: Fluorescence Spectroscopy

[0072] Sodium caseinate solution was used as the experimental sample. The pH was adjusted to 7, 8, 9, 10, 11, and 12, respectively, and stirred for 1 h. Then, the pH of all five solutions was adjusted to 12 and stirred for 1 h. The pH was then adjusted back to 7, 8, 9, 10, and 11, respectively, and fluorescence spectroscopy was performed. The excitation wavelength was set to 280 nm, the emission wavelength to 290-500 nm, the excitation and emission slits to 5.0 nm, the scan rate to 240 nm / min, and the voltage to 600 V. Before measurement, the baseline was zeroed using diluent. The fluorescence spectroscopy results show that sodium caseinate exhibits a red shift and quenching of fluorescence during alkaline treatment. This indicates that strong alkalinity leads to a loose protein structure, making the microenvironment of tryptophan more hydrophilic. During the process of adjusting from alkalinity back to neutrality, the maximum absorption peak of sodium caseinate shows a blue shift and the fluorescence intensity gradually increases, indicating that the structure re-shrinks and folds. This process can increase the binding rate of curcumin to sodium caseinate, which is a key factor in the preparation of high-performance water-soluble curcumin supports in Examples 1-5.

[0073] Experimental Example 4: Circular Dichroism Spectrum

[0074] Sodium caseinate, sodium caseinate-curcumin complex, and samples from Examples 4-5 were used as experimental samples for circular dichroism spectroscopy. A Jasco spectrophotometer was used to perform circular dichroism spectral analysis on the samples in the spectral range of 190–260 nm. The scan rate was 50 nm / min, and each sample was measured three times. The experimental results are as follows: As shown:

[0075] surface Sodium caseinate, sodium caseinate-curcumin complex, secondary structures of Examples 4-5

[0076]

[0077] The results showed that, compared with the secondary structure of sodium caseinate, the proportion of α-helices in the sodium caseinate-curcumin complex and in Examples 4-5 increased, while the proportion of random coils decreased. This indicates that the interaction between curcumin, β-cyclodextrin, and sodium caseinate altered the secondary structure of sodium caseinate. Compared with the secondary structure of the sodium caseinate-curcumin complex in Example 4, the proportions of α-helices, β-turns, and random coils increased, while the proportion of β-sheets decreased. This indicates that the introduced β-cyclodextrin inclusion complex interacted with sodium caseinate, leading to a change in the secondary structure of sodium caseinate. The introduction of maltodextrin altered the secondary structure of sodium caseinate in Example 4 by changing the interaction between sodium caseinate and β-cyclodextrin, resulting in a decrease in the proportions of α-helices and β-turns and an increase in the proportions of β-sheets and random coils.

[0078] Experimental Example 5: Transmission Electron Microscopy

[0079] Using sodium caseinate, β-cyclodextrin, and samples from Examples 4-5 as experimental samples, transmission electron microscopy (TEM) was performed. Freshly prepared curcumin supports diluted 10-fold with deionized water were dropped onto a copper grid and negatively stained with 1% (w / v) phosphotungstic acid. The morphology of the ultraamphiphilic molecule-mediated high-performance curcumin supports prepared in this invention was observed at 80,000x TEM under an accelerating voltage of 100 kV. The results of transmission electron microscopy show that both sodium caseinate and β-cyclodextrin exhibit relatively uniform spherical structures. The results of Examples 4-5 show that the system contains spherical structures of varying sizes, with smaller spheres embedded in larger ones. This indicates that smaller β-cyclodextrin particles enter the sodium caseinate particles, thus proving that the sodium caseinate and β-cyclodextrin inclusion complexes undergo supramolecular interactions to form supraamphiphilic curcumin nanoparticles.

[0080] Experiment Example 6: Atomic Force Microscope

[0081] Sodium caseinate, β-cyclodextrin, and the samples from Examples 4-5 were used for atomic force microscopy testing. 10 μl of the sample was added to a mica sheet, dried with nitrogen, and the microscopic images were scanned by tapping. The results from atomic force microscopy are similar to those from transmission electron microscopy. Sodium caseinate and β-cyclodextrin exhibit spherical structures with some aggregation. The systems of Examples 4 and 5 contain larger and non-uniformly sized particles that are spherical, indicating the formation of a sodium caseinate-curcumin-β-cyclodextrin complex with a particle size larger than that of sodium caseinate and β-cyclodextrin particles.

[0082] The above are merely preferred embodiments of the present invention and are used only to specifically explain the present invention. Any improvements, modifications, and optimizations made to the present invention based on its principles should also be considered within the scope of protection of the present invention.

[0083] Experiment Example 7 Load Rate

[0084] Using the high-performance curcumin support based on the modular construction of amphiphilic molecular base prepared in Examples 1-5 as experimental samples, the concentration of curcumin was determined by spectrophotometry, and the loading rate of curcumin was calculated.

[0085] pass The loading rate results show that the loading rates of Examples 1-5 are all greater than 5%, and the loading rates of Examples 3-5 are greater than 9%. The above results indicate that the high-performance curcumin support based on the modular construction of the superamphilic molecular base prepared in this invention has extremely high curcumin loading capacity.

[0086] Experimental Example 8: Average Particle Size and Zeta Potential

[0087] The water-soluble curcumin prepared in Examples 1-5 was used as the experimental sample. The average particle size and zeta potential of the particles were measured by a Zetasizer Nano ZS90 nanoparticle size potentiometer.

[0088] pass The average particle size results show that the average particle size of Examples 1-5 is less than 250 nm, indicating that the water-soluble curcumin particles prepared in Examples 1-5 are small, less prone to aggregation, and relatively stable. The maltodextrin introduced in Example 5 significantly reduced the average particle size of the system. The zeta potential results show that the absolute values ​​of the zeta potentials in Examples 1-5 are all greater than 25 mV, which indicates that the curcumin particles are more stable due to strong electrostatic repulsion.

[0089] Experimental Example 9: Resolubility

[0090] Using the water-soluble curcumin prepared in Examples 4-5 as the experimental sample, the curcumin support was redissolved in warm water at 35 °C. Under low-speed stirring, the powder was completely dissolved within 5 min. The water resolubility effects of the powders prepared in Examples 4 and 5 are respectively compared. The reconstitution results show that the reconstitution of Examples 4-5 is good, and they can be completely dissolved within 5 minutes without obvious clumping, sticking to the wall, or precipitation.

[0091] Experimental Example 10: Hygroscopicity

[0092] Using the water-soluble curcumin prepared in Examples 4-5 as experimental samples, 0.5 g of the prepared curcumin support powder was weighed and placed in a petri dish, spread evenly, and placed in a desiccator containing saturated sodium chloride solution for 7 days. The samples were then weighed and the hygroscopicity (percentage increase in weight) was calculated. The hygroscopicity of the curcumin support powder prepared in Examples 4-5 was 21.98% and 5.25%, respectively, which showed high resistance to moisture absorption and met the storage requirements of the food industry. In Example 5, the hygroscopicity was further reduced after the introduction of maltodextrin, indicating that maltodextrin has excellent resistance to moisture absorption.

[0093] Experimental Example 11: Light Transmittance

[0094] Using the water-soluble curcumin prepared in Examples 4-5 as experimental samples, the transmittance performance was tested. The curcumin support powder prepared in Examples 4-5 was dissolved in water to obtain a 1‰ sample aqueous solution. The absorbance in the system was measured at 680 nm, and the transmittance was calculated to be 85.42% and 95.28%, respectively. The results show that the reconstituted transmittance of Examples 4-5 is good, with high sensory value, which can meet the sensory needs of consumers for functional beverages.

[0095] Experimental Example 12 Thermal Stability

[0096] Using the water-soluble curcumin prepared in Examples 4-5 as experimental samples, a high-temperature destructive test was conducted. 60 mg of the water-soluble curcumin powder was dissolved in 10 ml of water and placed in a glass bottle. The sample was then heated at 95 °C for 120 min. The retention rate of curcumin was determined spectrophotometrically, and the average particle size was measured using a Zetasizer Nano ZS90 nanoparticle size potentiometer. The curves showing the retention rates of curcumin after rehydration in water of the powders prepared in Examples 4-5 are shown. The results indicate that the curcumin retention rates are 78.01% and 74.42%, respectively, demonstrating that Examples 4-5 exhibit excellent thermal stability. The figures show the average particle size variation over time after the powders prepared in Examples 4-5 were reconstituted in water. The results indicate that the average particle size of the powders prepared in Examples 4-5 changed little under high-temperature heat treatment. The system did not show significant changes in appearance or produce any undesirable phenomena such as precipitation under high-temperature heating.

[0097] Experimental Example 13: Light Stability

[0098] Using the water-soluble curcumin prepared in Examples 4-5 as experimental samples, a photodestructive test was conducted. 60 mg of the water-soluble curcumin powder was dissolved in 10 ml of water and placed in a glass bottle. The sample was then irradiated under a D65 light source (18 W) at a distance of 15 cm. Samples were taken out at specific time intervals, and the retention rate of curcumin was determined by spectrophotometry. The photodegradation retention curves obtained after the light-induced destructive test of Examples 4-5 are shown. After 120 h, the curcumin retention rates were measured to be 57.48% and 61.74%, respectively, indicating that Examples 4-5 have excellent photostability.

[0099] Experimental Example 14: Biological Accessibility

[0100] Using the water-soluble curcumin prepared in Examples 4-5 as experimental samples, the bioavailability of curcumin was tested by in vitro static digestion (the test method can refer to the standard INFOOGS 2.0 in vitro digestion method Brodkorb A. et al.[J]. Nature Protocols, 2019, 14(4): 991-1014.). The bioavailability of curcumin after digestion in Example 4 was 7.76%, which was 5.5 times higher than that of free curcumin after digestion; the bioavailability of curcumin after digestion in Example 5 was 12.26%, which was 8.7 times higher than that of free curcumin after digestion. The results show that Examples 4-5 have excellent bioavailability.

[0101] Experimental Example 15: Sugar-Acid Stability

[0102] Using the water-soluble curcumin prepared in Examples 4-5 as experimental samples, a sugar-acid stability destructive test was conducted. 12 mg of water-soluble curcumin powder was dissolved in 2 ml of water and placed in a glass bottle. 100 mg of sucrose was added to each sample solution. After stirring evenly, the pH was adjusted to 3 with citric acid. The resulting dispersions were allowed to stand for 30 min. The results showed that after 30 min, the curcumin retention rate of Example 4 was 92.98%, and the average particle size was 203.5 nm. The curcumin retention rate of Example 5 was 91.47%, and the average particle size was 140.3 nm. Examples 4-5 showed higher stability under sugar-acid conditions (pH=3) and smaller changes in average particle size.

[0103] Experimental Example 16: ABTS Free Radical Scavenging Rate

[0104] Using the water-soluble curcumin prepared in Examples 4-5 as the experimental sample, ABTS (7 mM) and K2S2O8 (2.45 mM) were mixed in deionized water to prepare an ABTS radical solution. The solution was incubated in the dark at 25 °C for 12 h and then diluted with 5 mM PBS (pH 7.4) to an absorbance of 0.70 ± 0.02 at 734 nm. 50 μl of the sample was added to 1 ml of the diluted ABTS+ solution, shaken for 0.5 min, and incubated in the dark for 5 min. The absorbance at 734 nm was measured. The total concentration of the sample was fixed at 2 mg / ml, and the curcumin concentration was fixed at 0.1 mg / ml. Free curcumin was prepared by dissolving curcumin (0.1 mg / ml) in ethanol. The formula for calculating the ABTS radical scavenging ability is as follows:

[0105]

[0106] Among them, A b Absorbance of ABTS blank at 734 nm before processing; As The absorbance of ABTS at 734 nm after treatment;

[0107] The ABTS radical scavenging rate of Example 4 was 82.43%, the ABTS radical scavenging rate of Example 5 was 76.69%, and the ABTS radical scavenging rate of free curcumin was 48.02%. The results show that the ABTS radical scavenging rates of Example 4 and Example 5 were significantly improved compared with those of free curcumin, which indicates that Example 4 and Example 5 have high antioxidant properties.

[0108] Experimental Example 17: Cohesion and Fluidity

[0109] Using the water-soluble curcumin prepared in Examples 4-5 as the experimental sample, cohesion and flowability tests were conducted. mg of nanoparticle powder was placed in a 10 ml graduated cylinder, the cylinder was gently tapped to remove powder adhering to the walls, and the volume (V) was recorded. B Then manually tap the graduated cylinder 50 times until the powder volume (V) is reached. T The bulk density (ρ) no longer changes. B ), bulk density (ρ) T The Carr index (C) and Hausnerby (HR) are calculated using the following formulas:

[0110]

[0111]

[0112]

[0113]

[0114] Example 4: The bulk density of the powder is 0.11 g / cm³. 3 The tap density is 0.14 g / cm³. 3 The Carr index was 0.19 and the Hausner-Nabi index was 1.23, indicating that the powder has good flowability and filling properties and can be easily transported through pipelines; the bulk density of the powder in Example 5 was 0.08 g / cm³. 3 The tap density is 0.10 g / cm³. 3 The Carr index was 0.16 and the Hausner index was 1.19, indicating that the powder has good flowability and filling properties and can be easily transported through pipelines.

[0115] It should be noted that 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 preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A high-performance curcumin support based on a modularly constructed superamphilic molecular base, characterized in that, It is composed of β-cyclodextrin, alkali-treated sodium caseinate, and curcumin; The method for preparing the curcumin support is as follows: β-cyclodextrin is used to encapsulate curcumin through host-guest interactions. Sodium caseinate is treated with alkali to expose hydrophobic groups and mix with the inclusion complex. The rigid macrocycle of the inclusion complex and the flexible open chain of the alkali-treated sodium caseinate are combined through non-covalent interactions to form a superamphilic molecule. Then, some curcumin is added to interact with the unbound hydrophobic sites. After stirring and sonication, the mixture is adjusted back to neutral with citric acid to induce the assembly into nanoparticles. Maltodextrin is added and the mixture is stirred, centrifuged, and spray-dried to obtain the final product. Specifically, the following steps are included: (1) Dissolve curcumin completely in ethanol solution to obtain solution A. Add β-cyclodextrin to deionized water and stir until completely dissolved to obtain solution B. Slowly add solution A dropwise to solution B and stir at 60°C until the ethanol is completely evaporated and the liquid color is uniform to obtain solution C. (2) Sodium caseinate was completely dissolved in deionized water and hydrated overnight. The pH was then adjusted to alkaline to obtain solution D. Curcumin was completely dissolved in solution D. Solution C was added to solution D and the pH was adjusted to 12. After sonication, the solution was stirred until the liquid color was uniform to obtain solution E. (3) Adjust the pH of solution E to neutral, stir until the liquid color is uniform, centrifuge and obtain the supernatant to obtain solution F; (4) Add the maltodextrin to the continuously stirred liquid F until the system is homogeneous; (5) The above homogeneous system is spray-dried to obtain the final product.

2. A method for preparing a high-performance curcumin support based on a modularly constructed amphiphilic molecular base, characterized in that, The curcumin support is composed of β-cyclodextrin, alkali-treated sodium caseinate, and curcumin. The preparation method involves encapsulating curcumin with β-cyclodextrin through host-guest interactions. Sodium caseinate is treated with alkali to expose hydrophobic groups, which are then mixed with the inclusion compound. The rigid macrocycle of the inclusion compound binds to the flexible open chain of the alkali-treated sodium caseinate through non-covalent interactions, forming a supraamophilic molecule. Then, some curcumin is added to interact with the unbound hydrophobic sites. After stirring and sonication, the mixture is adjusted back to neutral with citric acid to induce the assembly into nanoparticles. Maltodextrin is then added, followed by stirring, centrifugation, and spray drying to obtain the final product. Specifically, the following steps are included: (1) Dissolve curcumin completely in ethanol solution to obtain solution A. Add β-cyclodextrin to deionized water and stir until completely dissolved to obtain solution B. Slowly add solution A dropwise to solution B and stir at 60°C until the ethanol is completely evaporated and the liquid color is uniform to obtain solution C. (2) Sodium caseinate was completely dissolved in deionized water and hydrated overnight. The pH was then adjusted to alkaline to obtain solution D. Curcumin was completely dissolved in solution D. Solution C was added to solution D and the pH was adjusted to 12. After sonication, the solution was stirred until the liquid color was uniform to obtain solution E. (3) Adjust the pH of solution E to neutral, stir until the liquid color is uniform, centrifuge and obtain the supernatant to obtain solution F; (4) Add the maltodextrin to the continuously stirred liquid F until the system is homogeneous; (5) The above homogeneous system is spray-dried to obtain the final product.

3. The method for preparing curcumin support according to claim 2, characterized in that, In step (1), the mass ratio of β-cyclodextrin to curcumin is (1.6~4):

1.

4. The method for preparing curcumin support according to claim 2, characterized in that, In step (2), the mass ratio of sodium caseinate to curcumin in solution D is (2.4~4.8):

1.

5. The method for preparing curcumin support according to claim 2, characterized in that, In step (2), the solution is stirred at 500 rpm for 1 h.

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