Fructus liquidambaris triterpenoid microcapsule as well as preparation method and application thereof

Abstract

The invention provides a liquidambar formosana hance triterpenoid microcapsule and a preparation method thereof.The preparation method comprises the following steps that liquidambar formosana hance powder serves as a raw material, ultrasonic extraction is conducted through ethyl alcohol, then extraction is conducted through ethyl acetate, and a liquidambar formosana hance triterpenoid is obtained; maltodextrin and Arabic gum are mixed, water is added for dissolution, and a wall material solution is obtained; adding a fructus liquidambaris triterpenoid into the wall material solution, then adding glyceryl monostearate, and stirring to obtain an emulsion; and carrying out spray drying on the emulsion to obtain the liquidambar formosana triterpenoid microcapsule. The invention also provides application of the microcapsule in preparation of antibacterial drugs or antioxidant active drugs. The fructus liquidambaris triterpenoid extracted by the invention and the microcapsule based on the compound have better antibacterial and antioxidant activity; according to the microencapsulation method disclosed by the invention, the micro-capsule has better water solubility, is prevented from being invaded by gastric acid, achieves the effect of fully releasing in small intestines at a fixed point, and has the advantages of high slow-release stability and high utilization rate of effective components.

Description

Technical Field

[0001] The present invention relates to the field of biomedicine, and in particular to a microcapsule of a sedum triterpenoid compound and a preparation method and application thereof. Background Art

[0002] The Chinese herbal medicine Liquidambar formosana Hance is the dried mature infructescence of Liquidambar formosana Hance, a plant of the Hamamelidaceae family. It contains a variety of active ingredients, including triterpenoids, flavonoids, phenolic acids, volatile oils, etc. Among them, triterpenoids are important active substances in Liquidambar formosana, and have important application value in the fields of medicine, chemical industry, and agriculture.

[0003] Microencapsulation technology is a packaging technology that encapsulates active ingredients in tiny capsule shells, aiming to improve the stability and bioavailability of active ingredients. This technology can effectively control the release rate of drugs and prolong the half-life of drugs in the body, thereby increasing the efficacy of drugs and reducing side effects.

[0004] Based on this, we can try to develop a microcapsule of triterpenoid compounds of Lulutong for use in the field of biomedicine. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a microcapsule of triterpenoid compound of Lulutong and a preparation method and application thereof.

[0006] The present invention adopts the following technical solutions to solve the above technical problems:

[0007] A method for preparing microcapsules of triterpenoid compounds of Lulutong, comprising the following steps:

[0008] S1. Using the powder of Lulutong as raw material, firstly ultrasonic extraction was performed with ethanol, and then extraction was performed with ethyl acetate to obtain the triterpenoid compounds of Lulutong;

[0009] S2, mixing maltodextrin and gum arabic evenly, and then adding water to dissolve them to obtain a wall material solution;

[0010] S3, adding the fennel triterpenoid compound obtained in step S1 to the wall material solution, and then adding glyceryl monostearate, stirring to obtain an emulsion;

[0011] S4. The emulsion is subjected to spray drying treatment to obtain the desired microcapsules of the triterpenoid compound of Lulutong.

[0012] As one of the preferred embodiments of the present invention, in step S1, the specific preparation method of the triterpenoid compound of Lulutong is:

[0013] (1) Take fennel powder, add ethanol, the alcohol-water ratio is 80%, the solid-liquid ratio is 1:10 (g / mL), ultrasonic time is 0.5h, and the ultrasonic temperature is 60°C to obtain ethanol extract, filter and reduce the pressure to recover ethanol to obtain ethanol crude extract;

[0014] (2) suspending the crude ethanol extract with distilled water, and then extracting with petroleum ether, dichloromethane, ethyl acetate, and n-butanol in sequence, taking the ethyl acetate layer, and then recovering the ethyl acetate under reduced pressure to obtain the ethyl acetate extract, which is the triterpenoid compound of the Rhizoma Lulutongae.

[0015] As one of the preferred embodiments of the present invention, in step S1, the obtained Rhizoma Lulutong triterpenoids have antibacterial and antioxidant activities.

[0016] As one of the preferred embodiments of the present invention, in step S2, the mixing mass ratio of maltodextrin to gum arabic is 1:1 (g / g), and the concentration of the wall material solution is 2-10%.

[0017] As one of the preferred embodiments of the present invention, in step S3, the radix lupulinae triterpenoids are used as the core material, maltodextrin and gum arabic are used as the wall material, and the core-to-wall mass ratio is 1:(5-25) (g / g).

[0018] As one of the preferred embodiments of the present invention, in step S3, the amount of glyceryl monostearate added is such that the final concentration reaches 1%.

[0019] As one of the preferred embodiments of the present invention, in step S4, the inlet air temperature of the spray drying is 160-200°C.

[0020] As one of the preferred embodiments of the present invention, the wall material solution concentration, core-to-wall mass ratio, and spray drying temperature are all determined by single-factor experiments combined with response surface analysis and actual operations; the final wall material solution concentration is 5.7%, the core-to-wall mass ratio is 1:12, and the inlet air temperature is 181°C.

[0021] A kind of Lulutong triterpenoid compound microcapsule is prepared according to the preparation method.

[0022] A use of the above-mentioned Lulutong triterpenoid compound microcapsules in the preparation of antibacterial drugs or antioxidant active drugs.

[0023] The advantages of the present invention compared to the prior art are:

[0024] The prepared microcapsules of the triterpenoid compound of Lulutong have good morphology, good fluidity, no agglomeration, and a special aromatic smell. The microcapsules meet the requirements of oral drugs in terms of solubility, bioavailability, targeting, biocompatibility, slow-release and other aspects.

[0025] The present invention has found that the extracted Rhizoma Lulutong triterpenoids have good antibacterial and antioxidant activities. The present invention adopts the Rhizoma Lulutong triterpenoids as the active ingredient, so that the prepared microcapsules have antibacterial and antioxidant activities, and through the microencapsulation method of the present invention, it can be made to have good water solubility, avoid being attacked by gastric acid, achieve the effect of full release in the small intestine, and have the advantages of high sustained-release stability and high utilization rate of effective ingredients, which can effectively reduce the dosage and toxic side effects. In addition, the embedding structure of the microcapsule of the present invention protects the antibacterial biomolecules, can prevent the destruction of the internal antibacterial components by ultraviolet light, and improve the stability of the effective ingredients. At the same time, the preparation process of the present invention is simple, the degree of automation is high, it is easy to expand production, and has very good application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is the morphological structure of the microcapsules of triterpenoid compounds of Lulutong under scanning electron microscope;

[0027] Figure 2 This is the infrared spectrum of the microcapsules of triterpenoid compounds of Lulutong;

[0028] Figure 3 This is the liquid chromatography-mass spectrometry analysis spectrum of the microcapsules of the triterpenoid compounds of Lulutong (in the figure, Figure A is the negative ion flow diagram; Figure B is the positive ion flow diagram);

[0029] Figure 4 This is the particle size distribution diagram of the microcapsules of the triterpenoid compounds of Lulutong;

[0030] Figure 5 is the standard curve of oleanolic acid;

[0031] Figure 6 This is the in vitro release state diagram of the microcapsules of triterpenoid compounds of Lulutong;

[0032] Figure 7 Effect of different temperatures on the antibacterial activity of ingredients before and after microencapsulation;

[0033] Figure 8 Effect of different treatment times on the antibacterial activity of ingredients before and after microencapsulation;

[0034] Fig. 9 The figure shows the effect of different UV irradiation time on the antibacterial activity of the ingredients before and after microencapsulation;

[0035] Fig.10 This is a graph showing the DPPH clearance test results of Lulutong triterpenoid compound microcapsules;

[0036] Fig.11 This is the result of the ABTS clearance test of Lulutong triterpenoid compound microcapsules;

[0037] Fig.12 OH for the microcapsules of triterpenoid compounds of Lulutong - Figure 1. Results of the clearance assay.

[0038] Fig.13 This is the effect of wall material concentration on embedding rate;

[0039] Fig.14 This is the effect of the core-to-wall ratio on the embedding rate;

[0040] Fig.15 The effect of inlet air temperature on embedding rate

[0041] Fig.16 It is a response surface diagram (in the figure, Figure A shows the effect of the interaction between wall material concentration and core-to-wall ratio on the embedding rate; Figure B shows the effect of the interaction between wall material concentration and inlet air temperature on the embedding rate; Figure C shows the effect of the interaction between core-to-wall ratio and inlet air temperature on the embedding rate). DETAILED DESCRIPTION

[0042] The following is a detailed description of the embodiments of the present invention. The embodiments are implemented based on the technical solution of the present invention, and detailed implementation methods and specific operation processes are given, but the protection scope of the present invention is not limited to the following embodiments. At the same time, the experimental methods used in the following embodiments are conventional methods unless otherwise specified; the materials, reagents, etc. used can be obtained from commercial channels unless otherwise specified.

[0043] Example 1

[0044] Preparation of Lulutong triterpenoids:

[0045] (1) Take the 60-mesh sieve of the tonglutong powder, add ethanol, the alcohol-water ratio is 80%, the solid-liquid ratio is 1:10 (g / mL), the ultrasonic time is 0.5 h, the ultrasonic temperature is 60°C, and the ethanol extract is obtained. After filtering, the ethanol is recovered under reduced pressure to obtain a crude ethanol extract.

[0046] (2) Take the crude ethanol extract, suspend it with twice the mass of distilled water, and then extract it with equal volumes of petroleum ether, dichloromethane, ethyl acetate, and n-butanol in sequence, then take the petroleum ether layer, dichloromethane layer, ethyl acetate layer, n-butanol layer, and water layer, and recover the solvent under reduced pressure to obtain a petroleum ether extract (yield 2.88±0.05%), a dichloromethane extract (yield 2.57±0.02%), an ethyl acetate extract (yield 0.99±0.03%), an n-butanol extract (yield 1.17±0.07%), and a water extract (yield 0.58±0.09%), wherein the ethyl acetate extract is the Spleen triterpenoid compound.

[0047] Example 2

[0048] Preparation of Lulutong triterpenoid compound microcapsules:

[0049] (1) Maltodextrin and gum arabic were mixed uniformly in a mass ratio of 1:1 (g / g), and then dissolved in water to obtain a wall material solution with a concentration of 2 wt %.

[0050] (2) According to the core-to-wall mass ratio of 1:5 (g / g), the Lulutong triterpenoid compound (core material) prepared in Example 1 was added to the wall material solution, and then monostearate was added to make its concentration 1wt%, and then stirred and high-speed sheared to form an emulsion.

[0051] (3) Setting the air inlet temperature to 160° C. for spray drying, thereby obtaining Lulutong triterpenoid compound microcapsules.

[0052] Example 3

[0053] Preparation of Lulutong triterpenoid compound microcapsules:

[0054] (1) Maltodextrin and gum arabic were mixed uniformly in a mass ratio of 1:1 (g / g), and then dissolved in water to obtain a wall material solution with a concentration of 10 wt %.

[0055] (2) According to the core-to-wall mass ratio of 1:25 (g / g), the Lulutong triterpenoid compound (core material) prepared in Example 1 was added to the wall material solution, and then monostearate was added to make its concentration 1wt%, and then stirred and high-speed sheared to form an emulsion.

[0056] (3) Setting the air inlet temperature to 200° C. for spray drying, thereby obtaining Lulutong triterpenoid compound microcapsules.

[0057] Example 4

[0058] Preparation of Lulutong triterpenoid compound microcapsules:

[0059] (1) Maltodextrin and gum arabic were mixed evenly in a mass ratio of 1:1 (g / g), and then dissolved in water to obtain a wall material solution with a concentration of 6%.

[0060] (2) According to the core-to-wall mass ratio of 1:10 (g / g), the Lulutong triterpenoid compound (core material) prepared in Example 1 was added to the wall material solution, and then monostearate was added to make its concentration 1wt%, and then stirred and high-speed sheared to form an emulsion.

[0061] (3) Setting the air inlet temperature to 180° C. for spray drying, thereby obtaining Lulutong triterpenoid compound microcapsules.

[0062] Example 5

[0063] Pharmacological experiments on triterpenoid compounds of Lulutong:

[0064] 1. Antibacterial test

[0065] Solution preparation required for the experiment:

[0066] LB (Luria-Bertain) medium: Tryptone 10 g, sodium chloride 10 g, yeast extract 5 g, distilled water to 1000 mL, adjust pH to 7.0, and sterilize.

[0067] Sample solution: 100 mg / L Lulutong triterpenoid compound (Example 1).

[0068] Inhibition zone diameter experiment: In a single-person clean bench, take 4 sterilized stoppered test tubes, put 5 mL of LB liquid culture medium in each, then aspirate 20 μL of E. coli and S. aureus into the test tubes, blow evenly with a pipette, cover tightly with a rubber cap, wrap with newspaper and seal, and place in a desktop constant temperature oscillator for culture. When E. coli and S. aureus are cultured to OD 600 When the value is about 0.5±0.2, you can spread the plate (take 50μL of cultured E.coli and S.aureus and spread it on LB solid medium with a spreader). Take the sterilized filter paper and place it evenly on the top, lower left and lower right of the culture dish, add the drug, blank control and positive control (kanamycin sulfate) to 30μL on the filter paper in small amounts and multiple times, place it in a 37℃ incubator and culture it for one day, observe, take pictures, and record the diameter of the inhibition zone.

[0069] The results showed that the diameter of the inhibition zone of the group of Lulutong triterpenoids was 8.2±0.37 (E. coli) and 8.1±0.26 cm (S. aureus). The inhibition rates of the other groups were inferior to that of the Lulutong triterpenoids group.

[0070] 2. Antioxidant Activity Test

[0071] The following antioxidant test was performed on different concentrations (0.125 mg / mL, 0.25 mg / mL, 0.5 mg / mL, 1 mg / mL, 2 mg / mL) of the triterpenoid sample solutions of Lulutong (Example 1) (with L-ascorbic acid solution as the positive control).

[0072] (1) Determination of DPPH free radical scavenging ability

[0073] Take 3mL DPPH solution (with anhydrous ethanol as solvent) (concentration 0.05mg / mL), add 1mL of sample solution of different concentrations, shake well, store at room temperature in the dark for 30min, and measure the absorbance at a wavelength of 517nm, which is recorded as A S; Take another 3mL DPPH solution, add 1mL anhydrous ethanol, and measure the absorbance A C ; Simultaneously measure 3mL of anhydrous ethanol solution, add 1mL of sample solution of different concentrations, and record the absorbance A j The above test was repeated three times and the average value was taken.

[0074] The DPPH free radical scavenging rate was calculated according to the following formula:

[0075]

[0076] Where A C : Blank control absorbance; A j : Background absorbance of solutions with different concentrations; A S : Absorbance at different concentrations.

[0077] The results showed that the DPPH free radical scavenging ability of Lulutong triterpenoids increased with the concentration after embedding. At a high concentration of more than 0.5 mg / mL, there was no significant difference in the free radical scavenging rate before and after embedding (P>0.05).

[0078] (2) Determination of ABTS free radical scavenging ability

[0079] Preparation of ABTS: Take 5mL 7mmol / L ABTS (3.84mg / mL), add 88μL 140mmol / L potassium persulfate (3.77mg / mL) and mix, and place in dark place at room temperature for 12-16h to obtain ABTS mother solution; take anhydrous ethanol and mix with the mother solution, dilute at a ratio of 1:60, adjust the absorbance at 734nm to 0.700±0.020, and obtain ABTS working solution, preheat at 30℃ and set aside.

[0080] Pipette 10 μL of sample solution of different concentrations, add 100 μL of ABTS working solution to each concentration, mix well, react for 6 minutes at room temperature in the dark, and measure the absorbance A at a wavelength of 734 nm. C ; Control group: Take 10 μL of anhydrous ethanol, add 100 μL of ABTS working solution, mix well, react at room temperature in the dark for 6 minutes, and measure the absorbance A at a wavelength of 734 nm B The results were measured three times in parallel and the average value was taken.

[0081] The ABTS free radical scavenging rate was calculated according to the following formula:

[0082]

[0083] The results showed that the ABTS free radical scavenging ability of Lulutong triterpenoid compounds increased slightly with the increase of concentration before and after encapsulation. Except for the significant decrease in free radical scavenging rate after encapsulation at a concentration of 1 mg / mL (P<0.05), there was almost no significant difference in free radical scavenging rate before and after encapsulation at other concentrations greater than 0.25 mg / mL (P>0.05).

[0084] (3) Hydroxyl radical scavenging ability

[0085] The Fenton method was used to determine the ultrasonic extraction of volatile oil. · OH scavenging ability:

[0086] Pipette 10μL 4.5mmol / L ferrous sulfate and 10μL 4.5mmol / L salicylic acid-ethanol solution, add 15μL sample solution and 105μL distilled water, and finally add 10μL 10mmol / L hydrogen peroxide; heat in a 37℃ water bath for 30min; measure the absorbance at 510nm, recorded as A X Same as above, but 10 μL of distilled water is used instead of 10 μL of 10 mmol / L hydrogen peroxide, which is recorded as A. X0 Set the blank control variable, replace the sample solution with 15 μL of distilled water as A0, and calculate according to the following formula:

[0087]

[0088] The results showed that the triterpenoids of Lulutong had an effect on OH before and after embedding. - The free radical scavenging ability increased with the increase of concentration. When the concentration was 2 mg / mL, there was no significant difference in the free radical scavenging rate before and after embedding (P>0.05). When the concentration was lower than this, the free radical scavenging rate after embedding decreased slightly (P<0.05).

[0089] Example 6

[0090] Determination of Lulutong triterpenoid microcapsules:

[0091] The microcapsules of the triterpenoid compound of Lulutong prepared in the present invention (Example 4) were subjected to scanning electron microscopy, infrared spectrometry, liquid chromatography-mass spectrometry analysis and particle size analysis, and the results were as follows:

[0092] 1. Scanning electron microscopy analysis of microcapsule morphology

[0093] Scanning electron microscopy images of the microcapsules of triterpenoid compounds of Lulutong Figure 1 shown.

[0094] 2. Infrared spectrum analysis of microcapsules

[0095] The infrared spectrum of the microcapsules of triterpenoid compounds of Lulutong is shown in Figure 2As shown in the infrared spectrum of the core material, 3428cm -1 The OH bond stretching vibration absorption peak is at 2935cm, which indicates the widespread existence of hydroxyl groups in the extract of triterpenoid compounds of Lulutong. These hydroxyl groups are important functional groups in the structure of triterpenoid compounds and are closely related to their water solubility and biological activity; -1 The stretching vibration of the CH bond reflects the presence of alkyl components in triterpenoids, indicating that the molecule contains a long carbon chain structure; 1704cm -1 The peak at 1614cm is the stretching vibration peak of carbonyl C=O, indicating the possible presence of keto or acidic carbonyl functional groups in the structure of triterpenoids, which is an important functional group in triterpenoids; -1 1515cm is the stretching vibration peak of C=C double bond, especially in aromatic ring or unsaturated fatty chain; -1 and 1459cm -1 The 1380 cm-1 region is the bending vibration of the CH bond, especially in alkyl and aromatic rings; -1 The bending vibration of the CH bond, especially in the methyl (CH3) group, indicates the presence of methyl groups in the triterpenoids of Lulutong (core material); 1208cm -1 and 1121cm -1 1037cm is the stretching vibration peak of CO bond, especially in ether, alcohol or phenol, indicating the presence of oxygenated functional groups such as ether or alcohol groups; 1037cm -1 The peak at 586 cm is the stretching vibration peak of the COC bridge bond, indicating a possible ether connection or sugar connection, which is a typical structural feature of triterpenoids; -1 The difference may be related to some special environment or impurities of the sample.

[0096] From the infrared spectrum of the wall material, we can see that 3425cm -1 The OH bond stretching vibration absorption peak is at 2924cm. In maltodextrin and gum arabic, hydroxyl groups are abundant, which is part of their structure and is responsible for forming hydrogen bonds and maintaining water solubility. -1 The stretching vibration of the CH bond indicates that there are long carbon chains or alkyl components in maltodextrin and gum arabic; 1642 cm -1 The peak at 1423cm is the stretching vibration peak of C=O, indicating the existence of amide bond, which may come from the protein component in gum arabic. -1 The bending vibration of the CH bond reflects the presence of the alkyl component; 1158cm -1 The stretching vibration of the C-O-C bond is at 1023 cm. In maltodextrin and gum arabic, this may represent the glycosidic bond in the polysaccharide structure. -1854cm is the stretching vibration peak of CO bond, especially in polyols and polysaccharides, indicating the rich carbohydrate structure in maltodextrin and gum arabic; -1 The peak at 577cm is the stretching vibration peak of the COC bond, especially the characteristic vibration of the α-glycosidic bond, indicating the ring structure of the sugar molecule; -1 The presence of these sites may be related to impurities or specific structural features of a particular sample.

[0097] From the infrared spectrum of the microcapsules, we can see that 3425cm -1 The OH bond stretching vibration absorption peak is at 2921cm, which may be the hydroxyl vibration of triterpenoids or other phenolic acid compounds; -1 The stretching vibration of the CH bond should be present, indicating that the microcapsules contain aliphatic organic compounds; 1735cm -1 The peak at 1631 cm is the stretching vibration peak of carbonyl C=O, which may indicate the degree of esterification in the microcapsule material or the ketone group in the triterpenoid compound; -1 The peak at 1420cm is the stretching vibration peak of the C=C double bond, which is common in unsaturated fatty acids or aromatic rings. This may reflect the unsaturated nature of triterpenoids or the presence of other aromatic compounds; -1 The bending vibration of the CH bond may indicate the methyl and methylene groups in the microcapsule wall material or the lulutong component; 1251 cm -1 The peak at 1025cm is the stretching vibration peak of CO bond, which may indicate the degree of glycosylation in maltodextrin and gum arabic and the presence of triterpenoids; 1 The stretching vibration peak of the COC bond at 577 cm suggests the presence of polysaccharide or carbohydrate structure, which is the characteristic of maltodextrin and gum arabic. -1 The presence of impurities or specific structural features of the specific sample may be related to this. For Lulutong microcapsules, this may point to special structures or impurities formed during the microcapsule preparation process.

[0098] 3. Microcapsule liquid chromatography-mass spectrometry analysis spectrum

[0099] The composition of the microcapsules of triterpenoid compounds in Lulutong Figure 3As shown, first, the data file was opened using Xcalibur software to view the primary mass spectrum to obtain the mass-to-charge ratio and relative abundance of the compound. Then, the characteristic peaks were selected for secondary mass spectrometry analysis, and the compound structure was inferred by fragment ions. The compound name was finally determined by combining the relevant literature on Lulutong with databases such as HMDB and PubChem for matching. The output results included key data such as mass-to-charge ratio, retention time, response value, and metabolite information. The triterpenes (oleanolic acid, xinganximoside, scutellaria baicalensis glycoside, etc.) and phenolic acids (gallic acid, ellagic acid, etc.) in the Lulutong triterpenoid compound microcapsules had higher responses. In addition, there were active substances such as flavonoids (liquiritigenin), anthraquinones (Catenarin), and esters (cinnamyl cinnamate, quassinolide).

[0100] 4. Microcapsule particle size analysis

[0101] The particle size distribution range of the microcapsules of the triterpenoid compound of Lulutong prepared by the present invention is 1.61 μm to 20.09 μm. Figure 4 shown.

[0102] 5. Microcapsule embedding rate

[0103] The embedding rate of the Lulutong triterpenoid compound microcapsules prepared by the invention is 89.87%±0.23%.

[0104] 6. Microcapsule simulated in vitro gastrointestinal digestion sustained release test

[0105] Preparation of simulated gastric juice: Use a pipette to take 8.5 mL of concentrated hydrochloric acid with a mass concentration of 36-38%, and dilute it to 1000 mL with distilled water to obtain 0.1 mol / L hydrochloric acid (pH=1.2).

[0106] Preparation of simulated intestinal fluid: Take 6.8g of potassium dihydrogen phosphate, dissolve it in 250mL of distilled water by ultrasonication, add 190mL of 0.2mol / L NaOH and 400mL of distilled water, adjust the pH to 7.5, and continue to add water to make up to 1000mL.

[0107] In order to further explore the relationship between the in vitro sustained release after embedding and the triterpenoid components, oleanolic acid was used as an indicator, and the absorbance value was measured at a wavelength of 552nm by ultraviolet spectrophotometry. The absorbance values ​​corresponding to the oleanolic acid concentration range of 0.01, 0.04, 0.07, 0.10, 0.12, and 0.15 (mg / mL) were 0.056, 0.135, 0.234, 0.339, 0.411, and 0.494, respectively. The results showed that there was a good linear relationship within the concentration range of oleanolic acid. The regression equation results are as follows: Figure 5 , displayed as: y = 3.41079x-0.00595, r 2 =0.99546.

[0108] from Figure 6 It can be seen that in artificial gastric juice, the release rate is stable within 10%, indicating that under strong acidic conditions, the microcapsules have good protection of active substances and are not easily destroyed. Under artificial intestinal juice digestion, the release rate first increases with time and then tends to be flat. After 2.5 hours, the release rate of the microcapsules increases to more than 20%, indicating that the active substance is easier to release under weakly acidic conditions.

[0109] 7. Analysis of antibacterial activity of microcapsules

[0110] The turbidity observation of Lulutong triterpenoids (a) and Lulutong triterpenoids microencapsulated (b) in 96-well plates is shown in Table 1. Through turbidity observation, both the encapsulated and unencapsulated drugs have better effects on S. aureus, and the antibacterial rate increases with the increase of drug concentration. The minimum inhibitory concentration of Lulutong triterpenoids on E. coli is 25 mg / mL, and the minimum inhibitory concentration on S. aureus is 3.13 mg / mL. The minimum inhibitory concentration of Lulutong triterpenoids after microencapsulation on E. coli is 25 mg / mL, and the minimum inhibitory concentration on S. aureus is 6.25 mg / mL, indicating that the antibacterial activity before and after encapsulation has not changed significantly, and the active antibacterial components before encapsulation still exist after encapsulation.

[0111] Table 1 Drug concentration and antibacterial effect before and after embedding Turbidimetric observation

[0112]

[0113] Note: (a) indicates Lulutong triterpenoids; (b) indicates Lulutong triterpenoids microcapsules; “-” indicates no turbidity; “+” indicates turbidity.

[0114] The specific antibacterial rate is shown in Table 2. The specific antibacterial data before and after embedding are available. The specific antibacterial effect of the microcapsules after embedding is slightly lower than that before embedding at the same mass concentration, but overall, there is a certain antibacterial effect at the same concentration. We need to focus on protecting the stability of these substances and controlling their release behavior, rather than directly enhancing the antibacterial effect through technical treatment. It is worth noting that the embedding technology does not change the essential properties of the antibacterial substance, that is, its antibacterial effect mainly depends on the chemical structure and mechanism of action of the antibacterial substance itself. The embedding process only provides a more stable and controllable environment for the antibacterial substance to maintain the durability and stability of its antibacterial effect.

[0115] Table 2 Antibacterial rate of samples before and after embedding

[0116]

[0117] Note: (a) represents the triterpenoids of P. lupulina; (b) represents the microcapsules of the triterpenoids of P. lupulina; inhibition rate / %.

[0118] The results of the effects of different temperatures on the antibacterial activity of microencapsulated triterpenoids of Lulutong are shown in Figure 2. Figure 7 As shown. It can be obtained that with the increase of treatment temperature, the antibacterial effect of the embedded Lulutong triterpenoids is more stable than that of the unembedded Lulutong triterpenoids. When the temperature reaches 80°C, it can be seen that the antibacterial activity of the unembedded components begins to decrease significantly. When it reaches 100°C, the antibacterial effect of the unembedded components is greatly weakened, indicating that it does not show antibacterial effect under high temperature conditions and is sensitive to high temperature. The antibacterial effect of the embedded Lulutong triterpenoids is relatively gentle as the temperature increases, indicating that the active ingredients can still be well protected under high temperature conditions, so that it maintains a high efficiency of antibacterial ability.

[0119] The results of the effects of different time on the antibacterial activity of microencapsulated Lulutong triterpenoids are shown in Figure 2. Figure 8 The samples were placed in an oven at 25°C for different treatment times. It can be observed that with the increase of treatment time, the antibacterial ability of the unencapsulated samples of P. lulutong triterpenoids is gradually weakened. This shows that the unencapsulated samples are more susceptible to the influence of the external environment temperature and humidity, resulting in the gradual degradation or inactivation of the active ingredients (such as volatile active ingredients), while the embedded samples can maintain a good balance, indicating that the embedding technology effectively protects the active ingredients in the samples from the influence of the external environment.

[0120] Effect of ultraviolet irradiation on the antibacterial activity of microencapsulated triterpenoids of Lulutong Fig. 9 As shown. The samples were placed under ultraviolet light for different irradiation times. It can be observed that with the increase of treatment time, the antibacterial ability of the unembedded samples of Lulutong triterpenoids is in a trend of obvious weakening. This may be because the ultraviolet light has a destructive effect on certain antibacterial components in the sample, causing these components to lose or weaken their antibacterial ability. Since ultraviolet light is a high-energy electromagnetic wave, it can destroy the structure of biological molecules, including those with antibacterial functions; while the antibacterial ability of the microcapsules embedded with Lulutong triterpenoids remains stable, indicating that the embedding structure of the microcapsules plays a protective role and prevents the ultraviolet light from destroying the internal antibacterial components.

[0121] 8. Analysis of Antioxidant Activity of Microcapsules

[0122] Depend on Fig.10 , Fig.11 , Fig.12It can be seen that the DPPH scavenging rate of the Chinese medicine Lulutong extract increases with the increase of concentration. The positive control ascorbic acid can achieve a good antioxidant effect at a low concentration. The microcapsules and Lulutong triterpenoids have good scavenging ability when the concentration reaches 1mg / mL. The ABTS scavenging rate of the Chinese medicine Lulutong extract slowly increases with the increase of concentration. The positive control ascorbic acid has a good antioxidant effect at 0.5mg / mL. The microcapsules and Lulutong triterpenoids have weak overall ABTS scavenging ability. The hydroxyl radical scavenging rate of the Chinese medicine Lulutong extract increases with the increase of concentration. The positive control ascorbic acid has a strong antioxidant effect at a low concentration. The concentration of microcapsules and Lulutong triterpenoids needs to reach 1mg / mL to have a good hydroxyl radical scavenging effect. In summary, a comprehensive comparison of the microcapsules encapsulating active ingredients and the unencapsulated Rulutong triterpenoids shows that the antioxidant scavenging rates of both increase with increasing concentrations. The clearance rates of microcapsules and Rulutong triterpenoids are relatively close at high concentrations, and the microcapsules are slightly inferior to Rulutong triterpenoids at low concentrations. This may be due to the particle size distribution of the microcapsules, which causes their performance to fluctuate. It may also be because the encapsulated microcapsules have not been completely and effectively released, and the release time is not sufficient, resulting in a low antioxidant efficiency. In the future, we can further study the encapsulation material and reaction time to verify the relationship between the two in order to achieve the best antioxidant effect.

[0123] Example 7

[0124] Experiment on the influence of various factors on the performance of microcapsules:

[0125] 1. Effect of wall material concentration on microcapsule embedding efficiency

[0126] The wall material maltodextrin was mixed with gum arabic at a ratio of 1:1 (g / g), and water was added to stir to fully dissolve it. The wall material concentration was set to 2%, 4%, 6%, 8%, and 10%, and 1% monostearate was added. The stirring time was preferably 6 hours. The drug was accurately weighed and added to the wall material. The core-wall ratio was 1:15 (g / g). The stirring was continued by a magnetic stirrer for 6 hours to obtain a sample solution. The sample solution was placed in a spray dryer, and the air inlet temperature was set to 180°C for spray drying. The triterpenoid compounds of Lulutong were microencapsulated. Under different wall material concentration conditions, the microcapsule encapsulation rate was determined, and the influence of the conditions on the encapsulation rate was studied and analyzed. This experiment was repeated for 3 groups, and the results were averaged.

[0127] The microcapsule embedding rate of triterpenoid compounds in Lulutong was analyzed by using different wall material concentrations as the measurement index, such as Fig.13 As shown. Fig.13It can be seen that when the wall material concentration reaches 6%, the encapsulation rate is the highest, and the encapsulation rate trend increases first and then decreases with the increase of wall material concentration. When the wall material concentration is low, the encapsulation rate gradually increases with the increase of wall material concentration. This is because the proper increase in wall material concentration can provide more wall material molecules, which helps to form a more complete and dense encapsulation structure, thereby enhancing the encapsulation effect of triterpenoid compounds of Lulutong. However, when the wall material concentration is too high, the encapsulation rate will decrease instead.

[0128] 2. Effect of core-to-wall ratio on microcapsule embedding efficiency

[0129] The wall material maltodextrin was mixed with gum arabic at a ratio of 1:1 (g / g), and water was added to stir to fully dissolve it. The wall material concentration was fixed at 6%, and 1% monostearate was added. The stirring time was preferably 6 hours. The drug was accurately weighed and added to the wall material. The core-wall ratio was set at 1:5, 1:10, 1:15, 1:20, and 1:25 (g / g). The stirring was continued by a magnetic stirrer for 6 hours to obtain a sample solution. The sample solution was placed in a spray dryer, and the air inlet temperature was set to 180°C for spray drying. The triterpenoid compounds of Lulutong were microencapsulated. Under different core-wall ratios, the encapsulation efficiency of the microcapsules was determined, and the influence of the conditions on the encapsulation efficiency was studied and analyzed. This experiment was repeated for 3 groups, and the results were averaged.

[0130] By comparing the concentrations of different core-to-wall ratios, microcapsules of triterpenoids were prepared and their encapsulation efficiency was evaluated. Fig.14 shown.

[0131] When the core-to-wall ratio reaches 1:10 (g / g), the encapsulation rate is the highest. The encapsulation rate trend increases first and then decreases with the increase of wall material. When the wall material gradually increases (that is, the core-to-wall ratio gradually decreases), the encapsulation rate also increases, because the wall material can better wrap the core material. However, when the wall material increases to a certain extent, continuing to increase the amount of wall material will lead to a decrease in the encapsulation rate. This may be because excessive wall material will accumulate, overlap or form unnecessary structures when forming microcapsules, thereby affecting the overall quality and encapsulation effect of the microcapsules. When the core-to-wall ratio is 1:10 (g / g), the ratio of wall material to core material reaches a relatively ideal balance. The wall material can fully wrap the core material without being wasted due to excess, thus achieving the highest encapsulation rate.

[0132] 3. Effect of air inlet temperature on microcapsule embedding rate

[0133] Prepare a wall material of maltodextrin and gum arabic in a ratio of 1:1 (g / g), add water and stir to fully dissolve it, wherein the wall material concentration is fixed at 6%, add 1% monostearate glyceryl, and preferably stir for 6 hours, then accurately weigh the drug and add it to the wall material, the core-wall ratio is 1:15 (g / g), continue stirring with a magnetic stirrer, and stir for 6 hours to obtain a sample solution, place the sample solution in a spray dryer, set the inlet air temperature to 160℃, 170℃, 180℃, 190℃, and 200℃ for spray drying, and microencapsulate the triterpenoid compounds of Lulutong. Under different inlet air temperature conditions, the microcapsule encapsulation rate was determined, and the effect of this condition on the encapsulation rate was studied and analyzed. This experiment was repeated for 3 groups, and the results were averaged. The encapsulation rate formula is as follows:

[0134] Encapsulation efficiency % = m A / m0 (the ratio of the loaded drug mass to the total drug input).

[0135] Preparation of Lulutong triterpenoid microcapsules, comparison of the embedding rate at different inlet air temperatures, and analysis of Fig.15 As shown. When the inlet air temperature reaches 190°C, the encapsulation rate is the highest. The encapsulation rate trend increases first and then decreases with the increase of the inlet air temperature. Therefore, the inlet air temperatures of 180°C, 190°C, and 200°C were selected in this response surface experiment. As the inlet air temperature increases, the drying speed increases, which helps to complete the drying process in a shorter time, thereby avoiding the degradation or denaturation of the core material during the drying process. When the inlet air temperature is moderate (such as 190°C), the drying speed is fast enough to ensure that the wall material of the microcapsule forms a complete and dense mesh membrane structure before the core material degrades, thereby achieving a higher encapsulation rate, promoting the increase in drying speed and the complete formation of the microcapsule wall material. However, when the inlet air temperature is too high, the thermal effect begins to dominate, resulting in deformation or rupture of the microcapsule wall material, thereby reducing the encapsulation rate.

[0136] 4. Response surface experiment to optimize the preparation process

[0137] Through the results of single factor experiments, the wall material concentration of 2%, 4%, and 6%, the air inlet temperature of 180℃, 190℃, and 200℃, and the core-wall ratio of 1:5 (g / g), 1:10 (g / g), and 1:15 (g / g) were finally selected, and the encapsulation rate of triterpenoids of Lulutong was used as an indicator to screen out the best encapsulation process. The response surface factor level table is designed, as shown in Table 3.

[0138] Table 3 Response surface factor level table

[0139]

[0140] The Box-Behnken Design software was used for design and the optimized results were obtained through software analysis.

[0141] Combined with the single factor results, three-factor three-level response surface optimization was performed, and 17 experimental schemes were designed by Box-Behnken Design. The final equation represented by the coding factors was obtained by the response surface software result analysis: the encapsulation efficiency of active ingredients of Lulutong = 72.23 + 9.29A + 19.65B-2.36C + 1.57AB + 0.87AC-1.74BC + 2.84A 2 -20.88B 2 +3.04C 2 , where the absolute value of the coefficient indicates the significant effect of the factor on the response variable, the square term indicates the nonlinear effect of the factor, and the interaction term indicates the effect of the interaction between different factors on the response variable. Therefore: In this experimental result, the core-to-wall ratio factor has the most significant effect on the response variable.

[0142] The 3D response surface diagram was obtained by response surface software analysis. Fig.16 . Through the observation of the surface slope, the interaction between the wall material concentration and the inlet air temperature is small, which means that in the embedding process and in the optimization process, these two parameters can be adjusted relatively independently without worrying that the interaction between them will significantly affect the embedding effect; the wall material concentration and the core-to-wall ratio have a large interaction. When the wall material concentration and the core-to-wall ratio change at the same time, the interaction between them will have a significant effect on the performance of the microcapsule. For example, increasing the wall material concentration while keeping the core-to-wall ratio unchanged may improve the stability and encapsulation rate of the microcapsule, but if the core-to-wall ratio is reduced while the wall material concentration is increased, it may lead to insufficient drug loading, thereby reducing the embedding effect; the core-to-wall ratio and the inlet air temperature also have a large interaction, which is mainly reflected in the impact on the microcapsule drying process and the stability of the active ingredients of the drug. For example, increasing the core-to-wall ratio while keeping the inlet air temperature unchanged may increase the content of the drug inside the microcapsule, but it may also increase the difficulty of the drying process and the risk of drug degradation; while increasing the core-to-wall ratio and appropriately reducing the inlet air temperature, the risk of drug degradation can be reduced, but the drying time may be prolonged. Therefore, by rationally adjusting these parameters and their interactions, better encapsulation effects can be achieved, thereby ensuring the stability and effectiveness of the active ingredients of traditional Chinese medicine.

[0143] Table 4 Response surface model variance analysis of microencapsulation efficiency

[0144]

[0145]

[0146] Note: R 2 =0.9905; Radj 2 =0.9783

[0147] Table 5 Credibility analysis of microcapsule encapsulation efficiency model

[0148] average value / % Standard Deviation <![CDATA[R 2 ]]> <![CDATA[Adjusted R 2 > CV / % Precision 65.18 2.80 0.9905 0.9783 4.30 28.909

[0149] Combining the results in Table 4 and Table 5, it is known that the wall material concentration and the core-to-wall ratio have significant effects, among which the core-to-wall ratio has the greatest influence. The influencing factors were verified by variance analysis, and the final optimized conditions were obtained as follows: wall material concentration 5.75%, core-to-wall ratio = 1:11.947, inlet air temperature 180.81°C, and embedding efficiency 90.96%. For the convenience of the experiment, the wall material concentration was adjusted to 5.7%, core-to-wall ratio = 1:12, and inlet air temperature 181°C. The adjusted optimal process conditions were verified three times in parallel, and the microencapsulation embedding efficiency of Lulutong active substance was 89.87%.

[0150] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for preparing microcapsules of triterpenoid compounds of Lulutong, characterized in that: The steps include: S1. Using the powder of Lulutong as raw material, firstly ultrasonic extraction was performed with ethanol, and then extraction was performed with ethyl acetate to obtain the triterpenoid compounds of Lulutong; S2, mixing maltodextrin and gum arabic evenly, and then adding water to dissolve them to obtain a wall material solution; S3, adding the fennel triterpenoid compound obtained in step S1 to the wall material solution, and then adding glyceryl monostearate, stirring to obtain an emulsion; S4. The emulsion is subjected to spray drying treatment to obtain the desired microcapsules of the triterpenoid compound of Lulutong.

2. The method for preparing the microcapsules of Lulutong triterpenoid compounds according to claim 1, characterized in that: In the step S1, the specific preparation method of the triterpenoid compound of Lentulacus is as follows: (1) taking fennel powder, adding ethanol, the alcohol-water ratio is 80%, the solid-liquid ratio is 1:10, the ultrasonic time is 0.5 h, the ultrasonic temperature is 60° C., to obtain an ethanol extract, filtering and recovering ethanol under reduced pressure to obtain an ethanol crude extract; (2) suspending the crude ethanol extract with distilled water, and then extracting with petroleum ether, dichloromethane, ethyl acetate, and n-butanol in sequence, taking the ethyl acetate layer, and then recovering the ethyl acetate under reduced pressure to obtain the ethyl acetate extract, which is the triterpenoid compound of the Rhizoma Lulutongae.

3. The method for preparing the microcapsules of Lulutong triterpenoid compounds according to claim 1, characterized in that: In the step S1, the obtained Rhizoma Lulutong triterpenoids have antibacterial and antioxidant activities.

4. The method for preparing the microcapsules of Lulutong triterpenoid compounds according to claim 1, characterized in that: In the step S2, the mixing mass ratio of maltodextrin to gum arabic is 1:1, and the concentration of the wall material solution is 2-10%.

5. The method for preparing the microcapsules of Lulutong triterpenoid compounds according to claim 1, characterized in that: In the step S3, the triterpenoid compound of Lulutong is used as the core material, maltodextrin and gum arabic are used as the wall material, and the mass ratio of the core to the wall is 1:(5-25).

6. The method for preparing the microcapsules of Lulutong triterpenoid compounds according to claim 1, characterized in that: In the step S3, the amount of glyceryl monostearate added is such that the final concentration reaches 1%.

7. The method for preparing the microcapsules of Lulutong triterpenoid compounds according to claim 1, characterized in that: In step S4, the inlet air temperature of the spray drying is 160-200°C.

8. The method for preparing microcapsules of Lulutong triterpenoid compounds according to any one of claims 1 to 7, characterized in that: The wall material solution concentration, core-to-wall mass ratio, and spray drying temperature are all determined by single factor experiments combined with response surface analysis and actual operations; the final wall material solution concentration is 5.7%, the core-to-wall mass ratio is 1:12, and the inlet air temperature is 181°C.

9. A microcapsule of triterpenoid compound of Lulutong, characterized in that: It is prepared according to the preparation method according to any one of claims 1 to 8.

10. Use of the Lulutong triterpenoid compound microcapsules as claimed in claim 9 in the preparation of antibacterial drugs or antioxidant drugs.

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