Modified pseudo-ginseng exosome as well as intestinal conditioning gel composition and application thereof

Abstract

The invention relates to the technical field of functional food and biological medicine, in particular to a modified pseudo-ginseng exosome and an intestinal conditioning gel composition and application thereof. According to the gel beverage, an exosome derived from panax notoginseng callus cultured in a laboratory is used as a core active component, is modified through phosphatidylserine-aminated pectin-genipin and is embedded into a hydrogel matrix composed of carboxymethyl chitosan and sodium alginate, so that the exosome is protected from being degraded in the stomach, and the activity of the exosome in the stomach is improved. The exosome can be effectively released under the intestinal pH and flora environment, so that the targeted delivery of the intestinal tract is realized, and the preparation method is suitable for improving the intestinal inflammation and maintaining the intestinal health. The invention can effectively solve the technical problems of uncontrollable raw material quality and safety, low oral delivery stability and active ingredient availability and poor medication compliance of the existing plant exosome.

Description

Technical Field

[0001] This invention relates to the fields of functional food and biomedicine, and in particular to a modified Panax notoginseng exosome and its intestinal conditioning gel composition and application. Background Technology

[0002] Inflammatory bowel disease (IBD) is a group of diseases characterized by chronic intestinal inflammation, primarily including ulcerative colitis and Crohn's disease. Existing anti-inflammatory drugs for IBD, such as aminosalicylic acids, corticosteroids, and immunosuppressants, while able to control symptoms to some extent, have significant limitations. First, these drugs are usually administered systemically, lacking direct targeting to the intestines, and are prone to causing serious systemic side effects such as liver and kidney toxicity and bone marrow suppression. Second, long-term use easily leads to drug resistance, and their efficacy is limited for many patients.

[0003] In recent years, plant exosome-like nanoparticles have emerged as a novel bioactive delivery carrier, exhibiting excellent biocompatibility, low immunogenicity, and cross-species regulatory capabilities, showing great potential in disease treatment. Panax notoginseng, a traditional Chinese medicine, has had its extracts proven to possess anti-inflammatory, antioxidant, and tissue-repair-promoting effects. However, developing Panax notoginseng exosomes into oral formulations faces the following significant challenges: (1) Poor gastric environment stability: As a phospholipid bilayer structure, exosomes are easily destroyed by the strong acid environment of the stomach and the action of pepsin after oral administration, resulting in leakage of contents and loss of biological activity, making it difficult to reach the target site of the intestine intact.

[0004] (2) Low targeted delivery efficiency: Even if the exosomes are not destroyed in the stomach, they are easily cleared or non-specifically distributed in the gastrointestinal tract and cannot be effectively enriched in the intestinal inflammatory area, resulting in low bioavailability.

[0005] (3) Raw material quality and safety are uncontrollable: It is difficult to remove heavy metals and pesticide residues from Panax notoginseng grown in traditional fields during the exosome extraction process, making it impossible to achieve standardization and safety of the effective components of plant exosomes.

[0006] (4) Poor medication compliance: Some existing local intestinal drug formulations, such as suppositories and enemas, are inconvenient to use and have poor comfort, which seriously affects patients' long-term treatment compliance.

[0007] Therefore, there is a need to develop a novel oral formulation of Panax notoginseng exosomes that can overcome the above-mentioned defects. This formulation can effectively protect the exosomes as they pass through the stomach, be accurately delivered to the intestines and released slowly, and also have the characteristics of safe raw materials, stable quality and high patient compliance. Summary of the Invention

[0008] To address the shortcomings of existing technologies, the present invention aims to provide a modified Panax notoginseng exosome and its intestinal conditioning gel composition and application. This modified Panax notoginseng exosome exhibits high stability and good targeting, enabling targeted sustained release in the intestine, and can be used for the adjunctive improvement of IBD and intestinal health conditioning. The present invention effectively solves the technical problems of uncontrollable quality and safety of existing plant exosome raw materials, low oral delivery stability and utilization of active ingredients, and poor medication adherence.

[0009] To achieve the above-mentioned technical objectives, the present invention adopts the following technical solution: One technical solution of the present invention provides a modified Panax notoginseng exosome, the raw materials for preparation include Panax notoginseng exosome, phosphatidylserine, aminated pectin, and genipin; wherein, the mass ratio of Panax notoginseng exosome to phosphatidylserine is 1:(5-50); the mass ratio of phosphatidylserine, aminated pectin, and genipin is 1:(3.3-4.8):(2.0-3.5).

[0010] Furthermore, the mass ratio of Panax notoginseng exosomes to phosphatidylserine was 1:(10-20); the mass ratio of phosphatidylserine, aminolated pectin, and genipin was 1:(3.7-4.5):(2.5-2.9).

[0011] In some possible implementations, Panax notoginseng exosomes can be prepared by at least the following steps: After the Panax notoginseng callus tissue was broken and juiced, it was subjected to gradient centrifugation and filtration for sterilization to obtain purified Panax notoginseng exosomes.

[0012] Furthermore, the preparation steps of Panax notoginseng exosomes include: (1) After collecting the Panax notoginseng callus tissue grown in the clean laboratory, wash it with pure water, break the cell wall at room temperature, filter it, and obtain Panax notoginseng juice. (2) Perform low-speed gradient centrifugation on the Panax notoginseng juice sequentially: First, centrifuge at 1500-2500×g for 5-15 minutes, discard the precipitate, and take the supernatant; Centrifuge at 2500-3500×g for 20-40 minutes, discard the precipitate, and take the supernatant; Centrifuge at 10000-15000×g at 2-5℃ for 20-40 min, discard the precipitate, take the supernatant, and obtain a clear liquid containing Panax notoginseng exosomes; (3) Ultracentrifugation step (2) Filter the collected liquid containing Panax notoginseng exosomes, remove the supernatant, resuspend the precipitate with PBS, add trehalose at a mass-volume ratio of 3-8% as a protective agent, mix evenly, filter to remove bacteria, freeze dry, and obtain the exosomes containing Panax notoginseng.

[0013] In some possible implementations, in step (3), the ultracentrifugation conditions are: centrifugation temperature of 2-5℃, centrifugation force of 80000-120000×g, and centrifugation time of 0.5-1.5h.

[0014] In some possible implementations, in step (3), the filter membrane used for filtration and sterilization has a pore size of 0.22 μm.

[0015] This invention uses Panax notoginseng callus cultured in a clean laboratory as the source of exosomes, which can avoid the accumulation of heavy metals and the impact of pesticide residues. It also has high purity and large yield of effective substances, which can ensure the standardization and safety of the effective components of Panax notoginseng exosomes.

[0016] In some possible implementations, the preparation steps of aminated pectin include: (1) Dissolve pectin in water, add coupling agent 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) and catalyst N-hydroxysuccinimide (NHS), stir at room temperature to form an ester intermediate; (2) Add glucosamine to the ester intermediate obtained in step (1), stir until the reaction is complete, purify and freeze dry to obtain aminated pectin.

[0017] Furthermore, the preparation steps of aminated pectin include: (1) At room temperature, completely dissolve pectin in deionized water and adjust the pH of the system to 5.5-6.0 using 2-morpholinoethanesulfonic acid (MES) buffer. (2) At room temperature, EDC and NHS are dissolved in a small amount of MES buffer. Then, under continuous stirring, a mixed solution of EDC and NHS is added to the solution obtained in step (1). The mixture is stirred at 300-500 rpm for 30-60 min to generate a highly active NHS-ester intermediate. (3) Dissolve glucosamine hydrochloride in MES buffer to obtain glucosamine solution; add glucosamine solution to NHS-ester intermediate, and stir at 300-500 rpm for 12-24 h at room temperature in the dark. After the reaction is completed, purify and freeze dry to obtain loose, white aminated pectin powder.

[0018] In some possible embodiments, the mass ratio of pectin, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide, N-hydroxysuccinimide, and glucosamine is 1:0.5-1.0:0.2-0.7:1.0-1.5.

[0019] This invention provides a method for preparing modified Panax notoginseng exosomes according to any of the above-mentioned schemes, comprising at least the following steps: (1) Phosphatidylserine was embedded into the phospholipid bilayer of Panax notoginseng exosomes to obtain phosphatidylserine-modified exosomes; (2) The phosphatidylserine-modified exosomes from step (1) were mixed with an amino pectin aqueous solution, and then a genipin aqueous solution was added to carry out a cross-linking reaction to obtain modified Panax notoginseng exosomes.

[0020] Furthermore, the method for preparing modified Panax notoginseng exosomes includes at least the following steps: (1) Phosphatidylserine was dissolved in an organic solvent to form a lipid membrane. Then, PBS resuspension of Panax notoginseng exosomes was added and incubated at 35-40℃ with constant temperature shaking. After centrifugation, resuspension and sterilization, phosphatidylserine-modified exosome resuspension was obtained. (2) In an ice-water bath environment, an amino-modified pectin aqueous solution was added to the phosphatidylserine-modified exosomes, and after mixing evenly, a genipin aqueous solution was added, stirred and incubated in the dark. After centrifugation, resuspension, sterilization and freeze-drying, modified Panax notoginseng exosomes were obtained.

[0021] Furthermore, the preparation method of modified Panax notoginseng exosomes includes at least the following specific steps: (1) Dissolve phosphatidylserine (soybean source, purity ≥98%) in anhydrous ethanol, and sonicate it at 100-300W for 5-15 min in a water bath at 35-45℃ to obtain a homogeneous solution. Remove the anhydrous ethanol to obtain a phosphatidylserine lipid membrane. Add Panax notoginseng exocrine resuspension (pH 7.4, resuspended in PBS) to the phosphatidylserine lipid membrane, and incubate it at 35-40℃ with constant temperature shaking for 0.5-2.5 h. Then, centrifuge it at 2-5℃ with a centrifugal force of 80000-120000×g for 50-70 min to leave a precipitate. Resuspend the precipitate with a small amount of PBS and filter it through a 0.22μm filter membrane to obtain a high-purity phosphatidylserine-modified Panax notoginseng exocrine resuspension.

[0022] (2) In an ice-water bath at 2-5℃, add an amino-modified pectin aqueous solution to the phosphatidylserine-modified Panax notoginseng exosome suspension in step (1), mix thoroughly for 10-30 min to obtain a mixed solution; then add a genipin aqueous solution to the mixed solution, stir at 50-80 rpm and incubate in the dark for 15-20 min to obtain a clear solution containing modified Panax notoginseng exosomes; (3) The modified Panax notoginseng exosomes obtained in step (2) are subjected to ultracentrifugation. The precipitate is resuspended in PBS solution. Trehalose at a mass-volume ratio of 3-8% is added as a protective agent. After mixing evenly, the mixture is filtered to remove bacteria and then freeze-dried to obtain a loose white powder, which is the modified Panax notoginseng exosomes.

[0023] In some possible implementations, in step (3), the ultracentrifugation conditions are: centrifugation temperature of 2-5℃, centrifugation force of 80000-120000×g, and centrifugation time of 50-70min.

[0024] In some possible implementations, in step (3), the filter membrane used for filtration and sterilization has a pore size of 0.22 μm.

[0025] In the modified Panax notoginseng exosomes of this invention, phosphatidylserine is embedded in the phospholipid bilayer of the exosomes, forming a more stable membrane structure and enhancing membrane stability and gastric acid resistance. The carboxyl and hydroxyl groups in the aminated pectin structure can bridge with the phosphatidylserine on the exosome surface through ionic and hydrogen bonds, respectively, helping the exosomes to be more stably anchored in the mixed gel matrix. Simultaneously, the amino groups in the aminated pectin structure can react with genipin, bridging with stable CN covalent bonds, ultimately yielding modified Panax notoginseng exosomes with good stability, strong gastric acid resistance, and anti-inflammatory, antioxidant, and intestinal mucosal repair functions.

[0026] The present invention also provides an intestinal conditioning gel composition, the raw materials of which include modified Panax notoginseng exosomes, hydrogel matrix and water; In some possible implementations, the modified Panax notoginseng exosomes are the modified Panax notoginseng exosomes in the above scheme or the modified Panax notoginseng exosomes prepared by the above method; In some possible implementations, the hydrogel matrix includes carboxymethyl chitosan and sodium alginate; In some possible embodiments, the above-described intestinal conditioning gel composition further includes citric acid, erythritol, ascorbic acid, green tea polyphenols, red bean and blueberry leaf extract, potassium sorbate, and edible flavoring.

[0027] In some possible implementations, the intestinal conditioning gel composition comprises the following components by weight-volume percentage, based on the total volume of the composition: Modified Panax notoginseng exosomes 5-15%; Carboxymethyl chitosan 0.4-1%; Sodium alginate 0.2-0.8%; Citric acid 0.1-0.6%; Erythritol 1-5%; Ascorbic acid 0.02-0.15%; Green tea polyphenols: 0.01-0.1%; Red bean and blueberry leaf extract 0.01-0.1%; Potassium sorbate 0.03-0.1%; Food flavoring 0.02-0.2%; The remainder is water.

[0028] Furthermore, based on the total volume of the intestinal conditioning gel composition, the intestinal conditioning gel composition comprises the following components by weight-volume percentage: Modified Panax notoginseng exosomes 5-15%; Carboxymethyl chitosan 0.6-0.8%; Sodium alginate 0.3-0.5%; Citric acid 0.3-0.4%; Erythritol 2-3%; Ascorbic acid 0.08-0.12%; Green tea polyphenols: 0.02-0.05%; Red bean and blueberry leaf extract 0.05-0.08%; Potassium sorbate 0.05-0.07%; Edible flavoring 0.08-0.12%; The remainder is water.

[0029] In the intestinal conditioning gel composition of the present invention, carboxymethyl chitosan serves as the gelling main component, and sodium alginate and amino pectin-genipin complex are compounded together. The three components can form a polyelectrolyte complex through electrostatic interaction, which enhances the mechanical strength of the gel and forms a more stable gel network.

[0030] The red bean and blueberry leaf extract in this invention is rich in proanthocyanidins, which can undergo oxidative coupling reactions with catechins in tea polyphenols to generate novel dimer or polymer derivatives (the ortho-diphenol structure of anthocyanin is oxidized to quinone, which binds to the nucleophilic site of catechin to form stable CC or CO coupling products). These derivatives can be specifically degraded by probiotics such as Bifidobacteria and Lactobacillus, serving as a carbon source to promote their proliferation. After fermentation by probiotics, they generate short-chain fatty acids (SCFAs) such as butyric acid, which lower the intestinal pH and inhibit the growth of harmful bacteria. As end products of bacterial metabolism, SCFAs (butyric acid and propionic acid) can provide energy for intestinal epithelial cells and repair the mucosal barrier.

[0031] The addition of citric acid in this invention can adjust pH and improve flavor; ascorbic acid is used for antioxidation and protection of exosomes; erythritol is used to enhance sweetness while reducing calories; potassium sorbate can inhibit microorganisms, be used for system preservation, and extend storage time; edible flavorings such as lemon or passion fruit can be selected for flavoring, and the choice can be made according to needs, without specific restrictions on the types.

[0032] The intestinal conditioning gel composition based on modified Panax notoginseng exosomes in this invention can effectively block the erosion of exosomes by gastric acid and improve the stability of exosomes. At the same time, there are electrostatic interactions, hydrogen bonds or hydrophobic interactions between exosomes and carboxymethyl chitosan, which can enhance the density and viscoelasticity of the gel network. The phospholipid vesicle structure of the exosomes themselves provides additional water retention capacity, making the gel system more palatable and stable in storage. The gel composition can gradually swell or degrade under the environment of intestinal pH, enzymes, and flora, realizing the slow release of Panax notoginseng exosomes, improving bioavailability, and the resulting formulation is a gel jelly, which is more acceptable to consumers, has good medication compliance, and meets the development trend of modern functional foods.

[0033] The present invention also provides a method for preparing the intestinal conditioning gel composition of the above-mentioned scheme, comprising at least the following steps: (a) Carboxymethyl chitosan and sodium alginate were mixed evenly to obtain a hydrogel matrix; (b) Add citric acid, erythritol, and ascorbic acid to a portion of the water, stir and dissolve to obtain solution A; add green tea polyphenols and red bean and blueberry leaf extract to a portion of the water, stir and dissolve to obtain solution B; add potassium sorbate and edible flavoring to the remaining water, stir and dissolve to obtain solution C; (c) Mix the modified Panax notoginseng exosomes, solution B and solution C evenly, then add the hydrogel matrix, stir evenly, add solution A, stir and mix evenly, and then degas, fill and sterilize to obtain the intestinal conditioning gel composition.

[0034] In some possible implementations, the stirring speed in step (c) does not exceed 100 rpm and the stirring time is controlled between 2 and 10 min. In step (c), degassing is performed using a vacuum degassing machine with a vacuum degree of 0.08-0.1 MPa and a degassing time of 2-8 min; sterilization is performed using a water bath at 50-70℃ for 20-40 min.

[0035] The modified Panax notoginseng exosomes and intestinal conditioning gel composition provided by the present invention, as well as the modified Panax notoginseng exosomes and intestinal conditioning gel composition prepared by the preparation method provided by the above technical solution, can all be used to prepare food or medicine for improving intestinal inflammation or maintaining intestinal health.

[0036] The present invention has the following beneficial effects: (1) This invention uses phosphatidylserine, aminated pectin, and genipin to modify Panax notoginseng exosomes, which can effectively improve the stability and intestinal targeting of Panax notoginseng exosomes. The possible reason is that phosphatidylserine is embedded in the phospholipid bilayer of Panax notoginseng exosomes, forming a more stable membrane structure and enhancing membrane stability, thus providing the exosomes with the first layer of gastric acid resistance. Simultaneously, aminated pectin and genipin have good gastric acid resistance, and the aminated pectin-genipin complex coating layer constructed on the surface of the exosomes can further resist the damage of gastric acid to the exosome activity, providing the exosomes with the second layer of gastric acid resistance. Together, they improve the gastric acid resistance of the exosomes, helping to deliver more active exosomes into the intestine. Under the action of enzymes, the aminated pectin-genipin complex wrapped on the surface of exosomes will be gradually degraded, helping to release active exosomes more quickly, act on the lesion site, and improve the improvement effect. In addition, the carboxyl and hydroxyl groups in the aminated pectin structure can be bridged with phosphatidylserine on the surface of exosomes by ionic bonds and hydrogen bonds, respectively, and the amino groups in its structure can react with genipin to synergistically improve the intestinal targeting of Panax notoginseng exosomes, and finally obtain modified Panax notoginseng exosomes with good stability, gastric acid resistance and intestinal targeting.

[0037] (2) Using modified Panax notoginseng exosomes as the core active ingredient, combined with a hydrogel matrix and ingredients such as green tea polyphenols, ascorbic acid, and red bean and blueberry leaf extract, a multi-protection and delivery system was constructed. This system can encapsulate the exosomes to reduce their contact with gastric acid. During the gradual transport to the intestine, the gel layer containing the amino-pectin-genipin complex dissolves and slowly releases the exosomes, ensuring the activity and precise targeted release of the exosomes. Utilizing the advantages of the gel formulation, the stability and activity of the exosomes in the stomach are protected, allowing them to act directly on the intestinal inflammatory sites, exerting anti-inflammatory and immunomodulatory effects, and significantly improving the efficacy of inflammation improvement. (3) Safe and controllable source of exosomes: This invention first uses an industrially controllable plant callus culture method to obtain Panax notoginseng callus and its exosomes, which effectively avoids the problems of heavy metal enrichment and pesticide residue pollution; then, through specific extraction process, preparation process and formulation design, the structure and stability of Panax notoginseng exosomes are protected by multi-type membrane structure engineering design, realizing the standardized production of effective components of Panax notoginseng exosomes, and ensuring that the quality of each batch of products is stable, safe and reliable.

[0038] (4) Comfortable and convenient administration method: Compared with traditional intestinal administration gels such as suppositories, which have great inconvenience and discomfort, the product of this invention adopts an oral administration method, which can effectively improve the gastric acid resistance of exosomes and release exosomes in the intestine. This solves the problem of inconvenience in administration and achieves precise intestinal release, improving patient medication compliance and improvement effect, and is suitable for mass production. Attached Figure Description

[0039] Figure 1 TEM image of the prepared Panax notoginseng exosomes (Example 1); Figure 2 The particle size distribution diagram of the exosomes prepared in Example 1; Figure 3 TEM image of the modified Panax notoginseng exosomes prepared in Example 1; Figure 4 The particle size distribution diagram for the modified Panax notoginseng exosomes prepared in Example 1. Detailed Implementation

[0040] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. Although the description of the present invention will be presented in conjunction with preferred embodiments, this does not mean that the features of the invention are limited to these embodiments.

[0041] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments of the present invention are described in further detail below. Unless otherwise specified, the raw materials used in the following examples are all commercially available products, and the reagents are analytical grade reagents.

[0042] To address the issues of low quality and safety controllability of existing Panax notoginseng exosomes, poor stability after oral delivery to the intestine, and the inconvenience and poor comfort of existing local intestinal drug delivery formulations, which affect patients' long-term treatment adherence, this invention provides modified Panax notoginseng exosomes with high stability and good targeting. The modified Panax notoginseng exosomes are combined with carboxymethyl chitosan and sodium alginate hydrogel matrix, and scientifically combined with green tea polyphenols, red bean and blueberry leaf extract, ascorbic acid and other ingredients to prepare a gel composition, which can form an intelligent oral delivery system that protects exosomes in the gastric acid environment and provides sustained release in the intestinal environment, and can be used for the adjuvant improvement of IBD and intestinal health conditioning.

[0043] Preparation Example 1 This preparation example provides a modified Panax notoginseng exosome, which, by weight, comprises 5 parts Panax notoginseng exosome, 75 parts phosphatidylserine, 300 parts aminated pectin, and 200 parts genipin.

[0044] The mass ratio of Panax notoginseng exosomes to phosphatidylserine was 1:15; the mass ratio of phosphatidylserine, aminolated pectin, and genipin was 1:4:2.7.

[0045] In this preparation example, the above-mentioned Panax notoginseng exosomes were prepared through the following steps: (1) After collecting the Panax notoginseng callus tissue grown in the clean laboratory, wash it with pure water, break the cell wall and extract the juice at room temperature, and then filter it with medical gauze and nylon cloth in turn to remove plant residues and obtain Panax notoginseng juice. (2) The filtered Panax notoginseng juice was subjected to low-speed gradient centrifugation in sequence: Centrifuge at 2000×g for 10 min, discard the precipitate, and take the supernatant; Centrifuge at 3000×g for 30 minutes, discard the precipitate, and take the supernatant; Centrifuge at 12000×g at 4℃ for 30 min, discard the precipitate, take the supernatant, and obtain a clear liquid containing Panax notoginseng exosomes; (3) The supercentrifuged solution containing Panax notoginseng exosomes in step (2) was resuspended with PBS, and 5% trehalose was added as a protective agent. After mixing evenly, the solution was filtered through a 0.22 μm filter membrane and freeze-dried to obtain a loose white powder, which is Panax notoginseng exosomes. The supercentrifugation conditions were: centrifugation temperature of 4℃, centrifugation force of 100000×g, and centrifugation time of 1h. The aminated pectin described above in this preparation example was prepared through the following steps: (1) Weigh pectin, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide, N-hydroxysuccinimide and glucosamine in a mass ratio of 1:0.8:0.4:1.2. Stir the pectin magnetically for 3 hours at room temperature until it is completely dissolved in deionized water to form a homogeneous solution. Adjust the pH of the system to 6.0 using MES buffer. (2) Dissolve EDC and NHS in a small amount of MES buffer beforehand, and then add the mixed solution of EDC and NHS to the solution obtained in step (1) under continuous stirring. Stir at 400 rpm for 45 min at room temperature to generate a highly active NHS-ester intermediate. (3) Dissolve glucosamine hydrochloride in MES buffer to obtain glucosamine solution; slowly add glucosamine solution to NHS-ester intermediate by injection pump, stir at 400 rpm for 20 h at room temperature in the dark to allow the amino group of glucosamine to fully react with the activated ester group to form a stable amide bond. After the reaction is completed, transfer the crude product solution to a dialysis bag for purification, dialyze thoroughly with deionized water to remove unreacted small molecule reagents and byproducts, and then freeze dry to obtain loose, white aminated pectin powder.

[0046] The preparation method of modified Panax notoginseng exosomes provided in this example is as follows: (1) Dissolve phosphatidylserine powder (soybean source, purity ≥98%) in anhydrous ethanol, sonicate at 200W for 10 min in a 40℃ water bath to form a homogeneous solution, and then remove the anhydrous ethanol by rotary evaporation to obtain a phosphatidylserine lipid membrane; add Panax notoginseng exosome PBS resuspension to the phosphatidylserine lipid membrane, pH 7.4, incubate at 37℃ with constant temperature shaking for 1 h, and then centrifuge at 100000×g for 60 min at 4℃ to leave a precipitate; resuspend the precipitate with a small amount of PBS, and then filter through a 0.22μm filter membrane to obtain a high-purity phosphatidylserine-modified Panax notoginseng exosome resuspension; (2) In a 4℃ ice-water bath environment, add an amino-modified pectin aqueous solution (using water as solvent to prepare an amino-modified pectin aqueous solution with a mass-volume ratio of 0.3%) to the phosphatidylserine-modified Panax notoginseng exosome suspension in step (1), mix thoroughly for 20 min to obtain a mixed solution; then add a genipin aqueous solution (using water as solvent to prepare a genipin aqueous solution with a mass-volume ratio of 0.2%) to the mixed solution, stir at 60 rpm and incubate in the dark for 15 min to obtain a clear solution containing modified Panax notoginseng exosomes; (3) Centrifuge the solution containing modified Panax notoginseng exosomes in step (2) at 4°C with a centrifugal force of 100000×g for 60 minutes, resuspend the precipitate with PBS solution, add 5% trehalose by mass / volume ratio as a protective agent, mix well, filter with a filter membrane with a pore size of 0.22 μm, freeze dry to obtain a loose white powder, which is the modified Panax notoginseng exosomes.

[0047] Preparation Example 2 This preparation example provides a modified Panax notoginseng exosome, which, by weight, comprises 2 parts Panax notoginseng exosome, 20 parts phosphatidylserine, 90 parts aminolated pectin, and 50 parts genipin.

[0048] The mass ratio of Panax notoginseng exosomes to phosphatidylserine was 1:10; the mass ratio of phosphatidylserine, aminolated pectin, and genipin was 1:4.5:2.5.

[0049] In this preparation example, the preparation of Panax notoginseng exosomes, the preparation of aminated pectin, and the preparation of modified Panax notoginseng exosomes are all done using the same methods as in Preparation Example 1.

[0050] Preparation Example 3 This preparation example provides a modified Panax notoginseng exosome, which, by weight, comprises 7 parts Panax notoginseng exosome, 140 parts phosphatidylserine, 520 parts aminated pectin, and 400 parts genipin.

[0051] The mass ratio of Panax notoginseng exosomes to phosphatidylserine was 1:20; the mass ratio of phosphatidylserine, aminolated pectin, and genipin was 1:3.7:2.9.

[0052] In this preparation example, the preparation of Panax notoginseng exosomes, the preparation of aminated pectin, and the preparation of modified Panax notoginseng exosomes are all done using the same methods as in Preparation Example 1.

[0053] Preparation Example 4 This preparation example provides a modified Panax notoginseng exosome, which, by weight, comprises 5 parts Panax notoginseng exosome, 75 parts phosphatidylserine, 350 parts aminated pectin, and 150 parts genipin.

[0054] The mass ratio of Panax notoginseng exosomes to phosphatidylserine was 1:15; the mass ratio of phosphatidylserine, aminolated pectin, and genipin was 1:4.7:2.0.

[0055] In this preparation example, the preparation of Panax notoginseng exosomes, the preparation of aminated pectin, and the preparation of modified Panax notoginseng exosomes are all done using the same methods as in Preparation Example 1.

[0056] Preparation Example 5 This preparation example provides a modified Panax notoginseng exosome, which, by weight, comprises 5 parts Panax notoginseng exosome, 75 parts phosphatidylserine, 251 parts aminated pectin, and 249 parts genipin.

[0057] The mass ratio of Panax notoginseng exosomes to phosphatidylserine was 1:15; the mass ratio of phosphatidylserine, amino-modified pectin, and genipin was 1:3.3:3.3.

[0058] In this preparation example, the preparation of Panax notoginseng exosomes, the preparation of aminated pectin, and the preparation of modified Panax notoginseng exosomes are all done using the same methods as in Preparation Example 1.

[0059] Comparative Example 1 This comparative example provides a modified Panax notoginseng exosome without the addition of phosphatidylserine. By weight, its raw materials include 5.7 parts of Panax notoginseng exosome, an aqueous solution containing 344 parts of aminated pectin, and an aqueous solution containing 230.3 parts of genipin.

[0060] In this comparative example, the preparation of Panax notoginseng exosomes and the preparation of aminated pectin were carried out using the same methods as in Preparation Example 1.

[0061] The method for preparing modified Panax notoginseng exosomes in this comparative example is as follows: Aminated pectin aqueous solution was added to the resuspension of Panax notoginseng exosomes at 4℃ in an ice-water bath and mixed thoroughly for 20 min to obtain a mixed solution. Genipin aqueous solution was then added to the mixed solution, stirred at 60 rpm and incubated in the dark for 15 min. The mixture was then centrifuged at 100,000 × g for 60 min at 4℃, and the supernatant was discarded. The precipitate was resuspended in PBS, and trehalose at a mass-volume ratio of 5% was added as a freeze-drying protectant. After mixing evenly, the mixture was filtered through a 0.22 μm pore size filter membrane and freeze-dried to obtain the modified Panax notoginseng exosomes of this comparative example.

[0062] Comparative Example 2 This comparative example provides a modified Panax notoginseng exosome without added amino pectin, the raw materials of which, by weight, include 10.4 parts Panax notoginseng exosome, 155 parts phosphatidylserine, and an aqueous solution containing 414.6 parts genipin.

[0063] The mass ratio of Panax notoginseng exosomes to phosphatidylserine is 1:15.

[0064] In this comparative example, the preparation of Panax notoginseng exosomes was carried out using the same method as in Preparation Example 1.

[0065] The method for preparing modified Panax notoginseng exosomes in this comparative example is as follows: (1) Dissolve phosphatidylserine powder (soybean source, purity ≥98%) in anhydrous ethanol, sonicate at 200W for 10 min in a 40℃ water bath to form a homogeneous solution, and then remove the anhydrous ethanol by rotary evaporation to obtain a phosphatidylserine lipid membrane; add 1 mg / mL Panax notoginseng exosome PBS resuspension to the phosphatidylserine lipid membrane, pH 7.4, and incubate at 37℃ with constant temperature shaking for 1 hour, then centrifuge at 100000×g for 60 min at 4℃ to remove the unmodified lipid PS on the Panax notoginseng exosome membrane, leaving a precipitate; resuspend the precipitate with a small amount of PBS, and then filter through a 0.22μm filter membrane to obtain a high-purity phosphatidylserine-modified Panax notoginseng exosome resuspension; (2) In an ice-water bath at 4°C, add genipin aqueous solution to the phosphatidylserine-modified Panax notoginseng exosome suspension in step (1), stir at 60 rpm and incubate in the dark for 15 min to obtain a clear solution containing modified Panax notoginseng exosomes. (3) The solution containing modified Panax notoginseng exosomes in step (2) was centrifuged at 100,000 × g for 60 minutes at 4°C. The precipitate was resuspended with PBS solution. Trehalose at a mass-volume ratio of 5% was added as a freeze-drying protectant. After mixing evenly, the solution was filtered through a filter membrane with a pore size of 0.22 μm and freeze-dried to obtain the modified Panax notoginseng exosomes of this comparative example.

[0066] Comparative Example 3 This comparative example provides a modified Panax notoginseng exosome without the addition of genipin, which, by weight, comprises 7.6 parts of Panax notoginseng exosome, 115.5 parts of phosphatidylserine, and an aqueous solution containing 456.9 parts of aminated pectin.

[0067] The mass ratio of Panax notoginseng exosomes to phosphatidylserine is 1:15.

[0068] In this comparative example, the preparation of Panax notoginseng exosomes and the preparation of aminated pectin were carried out using the same methods as in Preparation Example 1.

[0069] The method for preparing modified Panax notoginseng exosomes in this comparative example is as follows: (1) Dissolve phosphatidylserine powder (soybean source, purity ≥98%) in anhydrous ethanol, sonicate at 200W for 10 min in a 40℃ water bath to form a homogeneous solution, and then remove the anhydrous ethanol by rotary evaporation to obtain a phosphatidylserine lipid membrane; add 1 mg / mL Panax notoginseng exosome PBS resuspension to the phosphatidylserine lipid membrane, pH 7.4, and incubate at 37℃ with constant temperature shaking for 1 hour, then centrifuge at 100000×g for 60 min at 4℃ to leave a precipitate; resuspend the precipitate with a small amount of PBS, and then filter through a 0.22μm filter membrane to obtain a high-purity phosphatidylserine-modified Panax notoginseng exosome resuspension; (2) In a 4℃ ice-water bath environment, add an amino-modified pectin aqueous solution to the phosphatidylserine-modified Panax notoginseng exosome suspension in step (1), mix thoroughly for 20 min to obtain a mixed solution; then stir at 60 rpm and incubate the mixed solution in the dark for 15 min to obtain a clear solution containing modified Panax notoginseng exosomes. (3) Centrifuge the solution containing modified Panax notoginseng exosomes in step (2) at 4°C with a centrifugal force of 100000×g for 60 minutes, resuspend the precipitate with PBS solution, add 5% trehalose by mass / volume ratio as a protective agent, mix well, filter with a filter membrane with a pore size of 0.22 μm, freeze dry, and obtain a loose white powder, which is the modified Panax notoginseng exosomes.

[0070] Comparative Example 4 This comparative example provides a modified Panax notoginseng exosome, which replaces the aqueous solution of aminated pectin with pectin. By weight, the raw materials include 5 parts of Panax notoginseng exosome, 75 parts of phosphatidylserine, an aqueous solution containing 300 parts of pectin, and an aqueous solution containing 200 parts of genipin.

[0071] The mass ratio of Panax notoginseng exosomes to phosphatidylserine is 1:15.

[0072] In this comparative example, the preparation of Panax notoginseng exosomes was carried out using the same method as in Preparation Example 1.

[0073] In this comparative example, the preparation method of modified Panax notoginseng exosomes is the same as in preparation example 1, except that the aminated pectin aqueous solution is replaced with a pectin aqueous solution.

[0074] Example 1 This embodiment provides an intestinal conditioning gel composition, which, based on the total volume of the intestinal conditioning gel composition, contains the following components by weight-volume percentage: The composition includes 10% modified Panax notoginseng exosomes, 0.7% carboxymethyl chitosan, 0.4% sodium alginate, 0.33% citric acid, 2.5% erythritol, 0.1% ascorbic acid, 0.04% green tea polyphenols, 0.07% red bean and blueberry leaf extract, 0.06% potassium sorbate, 0.1% food flavoring, and 85.7% purified water.

[0075] The modified Panax notoginseng exosomes used in this embodiment are the modified Panax notoginseng exosomes provided in Preparation Example 1.

[0076] The preparation method of the above-mentioned intestinal conditioning gel composition is as follows: (a) Mix 0.7 parts of carboxymethyl chitosan and 0.4 parts of sodium alginate evenly to obtain a hydrogel matrix; (b) Add 0.33 parts citric acid, 2.5 parts erythritol, and 0.1 parts ascorbic acid to a portion of purified water, stir and dissolve to obtain solution A; add 0.04 parts green tea polyphenols and 0.07 parts red bean and blueberry leaf extract to a portion of purified water, stir and dissolve to obtain solution B; add 0.06 parts potassium sorbate and 0.1 parts food flavoring to the remaining purified water, stir and dissolve to obtain solution C.

[0077] (c) Mix the modified Panax notoginseng exosomes, solution B and solution C evenly, then add the hydrogel matrix and stir at 70 rpm for 12 min. Then add solution A and stir gently at 70 rpm for 10 min. Place the resulting gel under a vacuum of 0.09 MPa for 5 minutes to degas, then immediately fill it into a 60℃ constant temperature water bath for 30 min to sterilize, and seal it to obtain the intestinal conditioning gel composition.

[0078] Example 2 This embodiment provides an intestinal conditioning gel composition, the components and the mass-volume percentage of each component are the same as in Example 1, the difference being that: the modified Panax notoginseng exosomes used in this embodiment are the modified Panax notoginseng exosomes provided in Preparation Example 2.

[0079] The preparation method of the intestinal conditioning gel composition in this embodiment is the same as that in Example 1.

[0080] Example 3 This embodiment provides an intestinal conditioning gel composition, the components and the mass-volume percentage of each component are the same as in Example 1, the difference being that: the modified Panax notoginseng exosomes used in this embodiment are the modified Panax notoginseng exosomes provided in Preparation Example 3.

[0081] The preparation method of the intestinal conditioning gel composition in this embodiment is the same as that in Example 1.

[0082] Example 4 This embodiment provides an intestinal conditioning gel composition, the components and the mass-volume percentage of each component are the same as in Example 1, the difference being that: the modified Panax notoginseng exosomes used in this embodiment are the modified Panax notoginseng exosomes provided in Preparation Example 4.

[0083] The preparation method of the intestinal conditioning gel composition in this embodiment is the same as that in Example 1.

[0084] Example 5 This embodiment provides an intestinal conditioning gel composition, the components and the mass-volume percentage of each component are the same as in Example 1, the difference being that: the modified Panax notoginseng exosomes used in this embodiment are the modified Panax notoginseng exosomes provided in Preparation Example 5.

[0085] The preparation method of the intestinal conditioning gel composition in this embodiment is the same as that in Example 1.

[0086] Example 6 This embodiment provides an intestinal conditioning gel composition, which, based on the total volume of the intestinal conditioning gel composition, contains the following components by weight-volume percentage: The composition of the product is as follows: modified Panax notoginseng exosomes 12.5%, carboxymethyl chitosan 0.6%, sodium alginate 0.3%, citric acid 0.3%, erythritol 2%, ascorbic acid 0.09%, green tea polyphenols 0.03%, red bean and blueberry leaf extract 0.05%, potassium sorbate 0.05%, edible flavor 0.08%, and purified water 84%.

[0087] The modified Panax notoginseng exosomes used in this embodiment are the modified Panax notoginseng exosomes provided in Preparation Example 1.

[0088] The preparation method of the above-mentioned intestinal conditioning gel composition is as follows: (a) Mix 0.6 parts of carboxymethyl chitosan and 0.3 parts of sodium alginate evenly to obtain a hydrogel matrix; (b) Add 0.3 parts citric acid, 2 parts erythritol, and 0.09 parts ascorbic acid to a portion of purified water, stir and dissolve to obtain solution A; add 0.03 parts green tea polyphenols and 0.05 parts red bean and blueberry leaf extract to a portion of purified water, stir and dissolve to obtain solution B; add 0.05 parts potassium sorbate and 0.08 parts food flavoring to the remaining purified water, stir and dissolve to obtain solution C.

[0089] (c) Mix 12.5 parts of modified Panax notoginseng exosomes, solution B and solution C evenly, then add hydrogel matrix, stir at 30 rpm for 20 min, then add solution A, stir at 30 rpm for 15 min, place the resulting gel under 0.08 MPa vacuum for 8 minutes to degas, then immediately fill into a container, place in a 50℃ constant temperature water bath for 40 min to sterilize, and seal to obtain the intestinal conditioning gel composition.

[0090] Example 7 This embodiment provides an intestinal conditioning gel composition, which, based on the total volume of the intestinal conditioning gel composition, contains the following components by weight-volume percentage: The composition includes 15% modified Panax notoginseng exosomes, 0.8% carboxymethyl chitosan, 0.5% sodium alginate, 0.4% citric acid, 3% erythritol, 0.12% ascorbic acid, 0.05% green tea polyphenols, 0.08% red bean and blueberry leaf extract, 0.07% potassium sorbate, 0.12% food flavoring, and 79.86% purified water.

[0091] The modified Panax notoginseng exosomes used in this embodiment are the modified Panax notoginseng exosomes provided in Preparation Example 1.

[0092] The preparation method of the above-mentioned intestinal conditioning gel composition is as follows: (a) Mix 0.8 parts of carboxymethyl chitosan with 0.5 parts of sodium alginate evenly to obtain a hydrogel matrix; (b) Add 0.4 parts citric acid, 3 parts erythritol, and 0.12 parts ascorbic acid to a portion of purified water, stir and dissolve to obtain solution A; add 0.05 parts green tea polyphenols and 0.08 parts red bean and blueberry leaf extract to a portion of purified water, stir and dissolve to obtain solution B; add 0.07 parts potassium sorbate and 0.12 parts food flavoring to the remaining purified water, stir and dissolve to obtain solution C.

[0093] (c) Mix 15 parts of modified Panax notoginseng exosomes, solution B and solution C evenly, then add hydrogel matrix, stir at 90 rpm for 8 min, then add solution A, stir at 90 rpm for 5 min, place the resulting gel under 0.1 MPa vacuum for 3 minutes to degas, then immediately fill into a container, place in a 70℃ constant temperature water bath for 20 min to sterilize, and seal to obtain the intestinal conditioning gel composition.

[0094] Comparative Example 1 This comparative example provides a gel composition whose components and the mass-volume percentage of each component are the same as those in Example 1, except that the modified Panax notoginseng exosomes used in this comparative example are the modified Panax notoginseng exosomes provided in Comparative Example 1.

[0095] The preparation method of the gel composition in this comparative example is the same as that in Example 1.

[0096] Comparative Example 2 This comparative example provides a gel composition whose components and the mass-volume percentage of each component are the same as those in Example 1, except that the modified Panax notoginseng exosomes used in this comparative example are the modified Panax notoginseng exosomes provided in Comparative Example 2.

[0097] The preparation method of the gel composition in this comparative example is the same as that in Example 1.

[0098] Comparative Example 3 This comparative example provides a gel composition whose components and the mass-volume percentage of each component are the same as those in Example 1, except that the modified Panax notoginseng exosomes used in this comparative example are the modified Panax notoginseng exosomes provided in Comparative Example 3.

[0099] The preparation method of the gel composition in this comparative example is the same as that in Example 1.

[0100] Comparative Example 4 This comparative example provides a gel composition whose components and the mass-volume percentage of each component are the same as those in Example 1, except that the modified Panax notoginseng exosomes used in this comparative example are the modified Panax notoginseng exosomes provided in Comparative Example 4.

[0101] The preparation method of the gel composition in this comparative example is the same as that in Example 1.

[0102] Performance testing The microstructure of the Panax notoginseng exosomes prepared in Example 1 and the modified Panax notoginseng exosomes were tested using transmission electron microscopy (TEM) and a particle size analyzer. The results are shown in [reference needed]. Figure 1-4 It can be seen that the modified Panax notoginseng exosomes have a decreased surface regularity and a larger average particle size compared to the original Panax notoginseng exosomes. This may be because phosphatidylserine is embedded in the lipid bilayer of the Panax notoginseng exosomes and plays a bridging role, forming an aminated pectin-genipin complex coating layer on the surface of the exosomes. Therefore, the surface regularity of the modified Panax notoginseng exosomes is worse and the average particle size is larger.

[0103] The performance of the gel compositions extracted in Examples 1-7 and Comparative Examples 1-4 was tested sequentially, as follows: (1) Gel strength: Inject the gel sample into a standard cylindrical sample cup, ensuring a smooth, bubble-free surface and consistent height across all sample groups. Place the gel sample in the center of the texture analyzer stage, aligning the probe with the sample center (using a planar cylindrical probe in uniaxial compression mode), and start the test. The probe compresses the sample vertically at a set rate (0.5 mm / s), recording the force-displacement curve in real time until the preset compressive strain (15%) is reached. Each sample is repeated at least three times, and the average value is taken. The slope of the linear elastic zone, i.e., the compressive modulus, is calculated in Pa (N / m²). The gel strength is expressed as the average compressive modulus (Pa) ± standard deviation. The results are shown in Table 1.

[0104] (2) Resistance to gastric acid and intestinal targeting: To verify the protective and sustained-release effects of the gel composition of the present invention on exosomes in the gastrointestinal environment, an in vitro simulated digestion experiment was conducted.

[0105] Experimental methods: The gel compositions extracted from Examples 1-7 and Comparative Examples 1-4 were subjected to gastric acid resistance tests and intestinal targeting tests in sequence.

[0106] Gastric acid resistance test conditions: simulated gastric juice, pH 1.5, containing pepsin, 37℃, shaking for 2 hours, and the exosome residual rate was measured. The calculation formula is: exosome residual rate (%) = exosome concentration in gel after artificial gastric acid treatment / exosome concentration in original gel * 100%; Intestinal targeting test conditions: simulated artificial intestinal fluid, pH 6.8, containing pancreatic enzymes and bile salts, 37℃, shaken for 2 hours, exosome release rate was measured, and exosome morphological integrity rate was observed by TEM. The exosome release rate was calculated as follows: exosome release rate (%) = exosome concentration in simulated intestinal fluid / exosome concentration in gel after artificial gastric acid treatment * 100%; exosome morphological integrity rate (%) = number of morphologically intact exosomes in the selected area / total number of exosomes in the selected area * 100%.

[0107] The test results are shown in Table 1.

[0108] Table 1. Properties of the gel composition

[0109] As shown in Table 1, the gel compositions obtained in Examples 1-3 and 6-7 possess excellent gel strength, gastric acid resistance, and intestinal targeting properties. Specifically, the gel strength is 1160-1370 Pa; after 2 hours in gastric fluid, the residual rate of modified Panax notoginseng exosomes is ≥72.2±3.1%, indicating that the gel composition can effectively block the destruction by gastric acid and significantly improve the gastric acid resistance of exosomes; after 2 hours in intestinal fluid, the release rate of modified Panax notoginseng exosomes is ≥61.5±5.0%, and the morphological integrity rate of modified Panax notoginseng exosomes is ≥81.3%, indicating that after entering the intestinal fluid, the gel composition can gradually swell and degrade, releasing exosomes, and the exosomes are relatively intact, demonstrating that this application can achieve the intestinal-targeted release effect of modified Panax notoginseng exosomes.

[0110] Compared with Example 1, the performance of Examples 4 and 3 shows that reducing or eliminating the amount of genipin is detrimental to the improvement of gel strength, gastric acid resistance, and intestinal targeting of the gel composition. This may be because: In the modified Panax notoginseng exosomes, reducing or eliminating the amount of genipin weakens its interaction with carboxymethyl chitosan and sodium alginate in the system, reducing the cross-linking density of the gel network and thus worsening gel strength. Furthermore, it affects the construction of the aminated pectin-genipin complex coating layer on the exosome surface, reducing the exosome's secondary gastric acid resistance. Combined with the relatively loose gel structure, gastric juice can more easily penetrate the gel and continuously damage the exosomes within it. Therefore, the exosome retention rate after 2 hours in gastric juice and the exosome morphological integrity rate after 2 hours in intestinal juice are reduced. Additionally, because the aminated pectin-genipin complex coating layer on the exosome surface is relatively sparse, it can be degraded by intestinal enzymes in a short time, helping to release the exosomes. Therefore, the exosome release rate after 2 hours in intestinal juice is higher.

[0111] Compared to Example 1, the performance of Examples 5 and 2 shows that the reduction or absence of aminated pectin is detrimental to the improvement of gel strength, gastric acid resistance, and intestinal targeting of the gel composition. This may be because the reduction or absence of aminated pectin reduces its reaction with genipin, resulting in a relative scarcity of genipin on the surface of the modified Panax notoginseng exosomes. On the one hand, this leads to a poorer interaction between the modified Panax notoginseng exosomes and carboxymethyl chitosan and sodium alginate, resulting in a lower cross-linking density of the gel network and thus a weaker gel strength. On the other hand… Given the relatively loose gel network and the sparse encapsulation layer of the aminated pectin-genipin complex on the surface of exosomes, the exosomes exhibit a second layer of reduced gastric acid resistance. This makes it easier for gastric juice to penetrate the gel and cause continuous damage to the exosomes. Consequently, the exosome retention rate after 2 hours in gastric juice and the exosome morphology integrity rate after 2 hours in intestinal juice both decreased. In addition, the sparse aminated pectin-genipin complex layer on the surface of exosomes is also more easily degraded by intestinal enzymes, thereby shortening the exosome release time. Therefore, the exosome release rate after 2 hours in intestinal juice increased.

[0112] Compared to Example 1, the gel composition obtained in Comparative Example 1 exhibited decreased gel strength, gastric acid resistance, and intestinal targeting. This may be due to the following reasons: The absence of phosphatidylserine hinders the formation of an aminated pectin-genipin complex coating layer on the exosome surface. On one hand, it affects the interaction between genipin and carboxymethyl chitosan and sodium alginate, reducing the density of the gel cross-linking network and resulting in a looser gel structure. This makes the gel more susceptible to gastric acid infiltration. Combined with the decreased gastric acid resistance of the exosomes themselves, this leads to the extensive destruction of exosomes during the gastric juice stage, significantly reducing the number of active exosomes entering the intestinal juice. Furthermore, the residual gastric juice in the gel may cause continuous damage to the exosome structure. Therefore, the gel strength, the exosome retention rate after 2 hours in gastric juice, and the exosome morphology integrity rate after 2 hours in intestinal juice all decreased significantly. In addition, since an aminated pectin-genipin complex coating layer cannot be formed on the exosome surface, the exosomes can be directly released into the intestinal juice without the action of intestinal enzymes, thus significantly increasing the exosome release rate after 2 hours in intestinal juice.

[0113] Compared to Example 1, the gel composition obtained in Comparative Example 4 showed decreased gel strength, gastric acid resistance, and intestinal targeting. This may be because: non-amino pectin cannot interact with genipin, and only a pectin coating layer can be formed on the surface of exosomes. Compared to the amino pectin-genipin complex coating layer, the cross-linking density of the gel structure synergistically constructed by the pectin layer, carboxymethyl chitosan, and sodium alginate is significantly reduced, resulting in decreased gel strength. Furthermore, the secondary gastric acid resistance provided by the pectin layer to the exosomes is weak and more easily decomposed by intestinal enzymes. Therefore, the exosome residual rate after 2 hours in gastric juice and the exosome morphological integrity rate after 2 hours in intestinal juice are significantly reduced, while the exosome release rate after 2 hours in intestinal juice is significantly increased.

[0114] Application examples The intestinal conditioning gel composition provided by this invention can be used to prepare foods or medicines that improve inflammatory bowel disease or maintain intestinal health. To further verify the biological efficacy of this invention, a colitis mouse model was induced using sodium dextran sulfate (DSS), and the improvement effect in the colitis mouse model was compared.

[0115] Modeling: Mice in the model group drank a 2.5% DSS solution for 7 days, while mice in the blank group drank physiological saline for 7 days.

[0116] Experimental groups: Mice with colitis were treated by gavage for 7 days with PBS (negative control group), the gel composition of Example 1 above (experimental group), and mesalazine (positive control group), respectively. 200 μL was administered by gavage daily. The degree of improvement of colitis in mice was detected. The results are shown in Table 2.

[0117] Table 2 Comparison of treatment results in mouse models of colitis

[0118] Based on the experimental phenomena and the data in Table 2, we can conclude that: The control group of normal healthy mice had the longest colon, the lowest level of inflammatory factors, and were in a normal physiological state, resulting in the lowest clinical score.

[0119] Negative control group: No treatment was given after DSS modeling. The colon was severely shortened, the level of inflammatory factors was the highest, about 4.5 times the normal level, and the clinical symptoms were the most severe, including rectal bleeding and weight loss.

[0120] Positive control group: The treatment effect was the best, the colon length was close to the normal level of the blank group, the inflammation control was the best, close to the normal level, and the clinical symptoms basically disappeared, close to the normal state.

[0121] Experimental group: The effect was close to that of the traditional drug mesalazine, indicating that the exosome gel composition of the present invention can effectively improve inflammatory bowel disease. However, compared with mesalazine, a first-line clinical drug, the exosome gel composition of this application has a higher safety profile. Specifically, mesalazine, as a chemically synthesized drug, can cause systemic side effects such as headache, nausea, and kidney damage with long-term use. In contrast, the gel composition of the present invention uses Panax notoginseng exosomes derived from natural plants as the core component, combined with food-grade formulations such as antioxidants, exhibiting excellent biocompatibility and safety, and avoiding the systemic toxicity problems of chemical drugs.

[0122] The excellent improvement effect of the intestinal conditioning gel composition of this application is due to the multiple biological activities of exosomes, such as anti-oxidation, immune regulation and mucosal repair, as well as the synergistic effect of ingredients such as green tea polyphenols, ascorbic acid, red bean and blueberry leaf extract in the formula, forming a complete improvement chain of "protection-targeting-repair", thus achieving good verified improvement effect.

[0123] Although the preferred embodiments of the present invention have been disclosed above, they are not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications to the technical solutions of the present invention by utilizing the methods and techniques disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solutions of the present invention shall fall within the protection scope of the technical solutions of the present invention.

Claims

1. A modified Panax notoginseng exosome, characterized in that, The raw materials for preparing the modified Panax notoginseng exosomes include Panax notoginseng exosomes, phosphatidylserine, aminolated pectin, and genipin; The mass ratio of Panax notoginseng exosomes to phosphatidylserine is 1:(5-50); the mass ratio of phosphatidylserine, aminolated pectin and genipin is 1:(3.3-4.8):(2.0-3.5).

2. The modified Panax notoginseng exosomes according to claim 1, characterized in that, The aminated pectin is prepared by at least the following steps: (1) Dissolve pectin in water, add coupling agent 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide and catalyst N-hydroxysuccinimide, stir at room temperature to form ester intermediate; (2) Add glucosamine to the ester intermediate obtained in step (1), stir until the reaction is complete, purify and freeze dry to obtain aminated pectin.

3. The modified Panax notoginseng exosomes according to claim 2, characterized in that, The mass ratio of pectin, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide, N-hydroxysuccinimide, and glucosamine is 1:0.5-1.0:0.2-0.7:1.0-1.

5.

4. A method for preparing the modified Panax notoginseng exosomes according to any one of claims 1-3, characterized in that, At least the following steps are included: (1) Phosphatidylserine was embedded into the phospholipid bilayer of Panax notoginseng exosomes to obtain phosphatidylserine-modified exosomes; (2) The phosphatidylserine-modified exosomes from step (1) are mixed with an amino pectin aqueous solution, and then a genipin aqueous solution is added to carry out a cross-linking reaction to obtain the modified Panax notoginseng exosomes.

5. An intestinal conditioning gel composition, characterized in that, Its raw materials include modified Panax notoginseng exosomes, hydrogel matrix and water; The modified Panax notoginseng exosomes are the modified Panax notoginseng exosomes according to any one of claims 1-3 or the modified Panax notoginseng exosomes prepared according to the method of claim 4; The hydrogel matrix comprises carboxymethyl chitosan and sodium alginate.

6. The intestinal conditioning gel composition according to claim 5, characterized in that, The gel composition also includes citric acid, erythritol, ascorbic acid, green tea polyphenols, red bean and blueberry leaf extract, potassium sorbate, and food flavoring.

7. The intestinal conditioning gel composition according to claim 6, characterized in that, Based on the total volume of the gel composition, it contains the following components by weight-volume percentage: Modified Panax notoginseng exosomes 5-15%; Carboxymethyl chitosan 0.4-1%; Sodium alginate 0.2-0.8%; Citric acid 0.1-0.6%; Erythritol 1-5%; Ascorbic acid 0.02-0.15%; Green tea polyphenols: 0.01-0.1%; Red bean and blueberry leaf extract 0.01-0.1%; Potassium sorbate 0.03-0.1%; Food flavoring 0.02-0.2%; The remainder is water.

8. A method for preparing the intestinal conditioning gel composition as described in claim 6 or 7, characterized in that, Includes the following steps: (a) Carboxymethyl chitosan and sodium alginate were mixed evenly to obtain a hydrogel matrix; (b) Add citric acid, erythritol, and ascorbic acid to a portion of the water, stir and dissolve to obtain solution A; add green tea polyphenols and red bean and blueberry leaf extract to a portion of the water, stir and dissolve to obtain solution B; add potassium sorbate and edible flavoring to the remaining water, stir and dissolve to obtain solution C; (c) Mix the modified Panax notoginseng exosomes, solution B and solution C evenly, then add the hydrogel matrix, stir evenly, add solution A, stir and mix evenly, and then degas, fill and sterilize to obtain the intestinal conditioning gel composition.

9. The method for preparing the intestinal conditioning gel composition according to claim 8, characterized in that, In step (c), the stirring speed does not exceed 100 rpm and the stirring time is controlled between 5 and 20 minutes. In step (c), degassing is performed using a vacuum degassing machine with a vacuum degree of 0.08-0.1 MPa and a degassing time of 2-8 min; sterilization is performed using a water bath at 50-70℃ for 20-40 min.

10. The intestinal conditioning gel composition of any one of claims 5-7, or the intestinal conditioning gel composition prepared by the method of any one of claims 8-9, for use in the preparation of food or medicine for improving intestinal inflammation or maintaining intestinal health.

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