Green preparation process of high pressure homogenization modified astragalus extract suitable for nuclear emergency uranium excretion

Abstract

In view to the technical problems that the existing astragalus extract nano modification usually adopts chemical modification and exists residual toxicity, and the conventional high pressure homogenization process parameter setting is blind and easy to cause particle secondary aggregation, the present application discloses a kind of green preparation process of high pressure homogenization modified astragalus extract suitable for nuclear emergency uranium excretion promotion, the present application uses astragalus decoction as raw material, prepares micron grade crude extract by water extraction and alcohol precipitation, prepares crude extract precursor solution, completes nanocrystallization modification by using 200 bar optimal pressure, in 35 DEG C constant temperature, 6 times circulation high pressure homogenization system, then is prepared by spray drying finished product.The present application optimizes parameters by cooperation, fully breaks up raw material agglomerates, retains active functional groups completely, avoids active component damage caused by high pressure excessive modification at the same time, and the specific surface area and uranium complexing potential of product are significantly improved.The whole process is green and residue-free, has strong repeatability, can be industrialized batch preparation, can stably supply qualified raw materials for nuclear emergency oral uranium excretion preparation, and has outstanding industrialization and emergency reserve value.

Description

Technical Field

[0001] This invention belongs to the field of green modification and large-scale preparation technology of natural plant extracts. Specifically, it relates to a high-pressure homogenized nano-Astragalus extract preparation process based on physical modification of a pure water system without the addition of chemical additives. It is suitable for the standardized and industrialized production of nuclear emergency evacuation raw materials. Background Technology

[0002] Astragalus extract, rich in polysaccharides, flavonoids, and other active components, possesses potential heavy metal chelation and antioxidant capabilities, making it a potential candidate raw material for promoting the elimination of radionuclide contamination. However, traditional water-extraction and alcohol-precipitation crude extracts of Astragalus have significant drawbacks: the particles exist in a micron-sized aggregate form, with active functional groups encapsulated and blocked, greatly limiting subsequent radionuclide chelation performance. Currently, mainstream nano-modification processes for natural extracts mostly employ chemical cross-linking and organic reagent-induced modification, which easily lead to chemical residues and cannot meet the safety requirements of oral nuclear emergency preparations.

[0003] Existing high-pressure homogenization technologies are mostly used in food texture improvement and emulsion refinement, but there is no directional homogenization process system optimized for uranyl ion complexation function. Conventional homogenization processes suffer from parameter blindness; too low a pressure fails to break up particle agglomeration and expose active sites, while too high a pressure leads to the degradation of Astragalus polysaccharides and flavonoid active components, and also causes secondary particle agglomeration, resulting in unstable final product performance and hindering large-scale, standardized production of nuclear emergency feedstock. Therefore, there is an urgent need to develop a high-pressure homogenization modification preparation process with controllable parameters, green and residue-free characteristics, and stable performance. Summary of the Invention

[0004] The technical problem this invention aims to solve is to address the shortcomings of existing technologies, such as severe agglomeration of crude Astragalus extract, blockage of active sites, residual chemical modification, lack of targeted homogenization process parameters, and unstable product performance. This invention provides a green preparation process for high-pressure homogenization modification of Astragalus extract that is suitable for nuclear emergency uranium venting. The entire process uses a pure water system for physical modification. By precisely controlling core parameters such as homogenization pressure, number of cycles, and temperature, the extract is nanoscale modified while retaining active components. The process is green, safe, and can be mass-produced.

[0005] Technical solution: A green preparation process for high-pressure homogenized modified Astragalus extract adapted for nuclear emergency uranium efflux, comprising the following steps: S1, Preparation of crude extract of Astragalus membranaceus: Astragalus membranaceus slices were selected and subjected to multi-stage water extraction. The optimal material-liquid ratio was 1:10, 1:10, and 1:5. The samples were extracted three times at a constant temperature of 80-95 °C for 1 h each time. All extract filtrates were combined, concentrated under reduced pressure, and then subjected to alcohol precipitation with 70% ethanol. After centrifugation and vacuum drying, unmodified micron-sized Astragalus membranaceus extract ARE was obtained. S2, preparation of homogeneous precursor solution: The prepared ARE powder is completely dissolved in water to prepare a homogeneous aqueous solution of 1.95~2.05 mg / mL. The solution is magnetically stirred at room temperature for 2 h to completely eliminate the agglomeration of solid particles and obtain a uniform and stable precursor solution. S3, Directional High-Pressure Homogenization Modification: The precursor liquid is injected into a high-pressure homogenizer, the equipment is set to a constant temperature of 35 ℃, the homogenization pressure is precisely controlled at 200 bar, the material is circulated and homogenized 6 times, and the homogenization flow rate is kept constant at 100 mL / min; the entire process uses only water as the dispersion medium and does not add any surfactants, chemical crosslinking agents, organic solvents or other chemical additives. S4, Drying treatment: After the homogenized modified aqueous solution was concentrated under reduced pressure, anhydrous ethanol was added to adjust the ethanol concentration of the system to 70%, and it was placed in a 4 ℃ environment for 12 h to be purified again. After centrifugation at 5000 r / min for 10 min, the precipitate was collected and vacuum dried to finally obtain the nano-sized high-pressure homogenized modified Astragali Radix Extract (HP-ARE).

[0006] Preferably, within the S3 pressure range of 50-600 bar, 200 bar is the optimal modification pressure: below 200 bar, the mechanical shear force and cavitation effect are insufficient, failing to effectively break up micron-sized particle aggregates, resulting in poor exposure of active functional groups; above 300 bar, the high-intensity mechanical action will damage the molecular structure of Astragalus polysaccharides and flavonoids, causing degradation of antioxidant active components and inducing secondary aggregation of nanoparticles, significantly reducing the product's nuclide complexation performance. Six cycles of homogenization can achieve uniform and refined particle size, ensuring consistent and stable product particle size and dispersibility. Below 200 bar, particle breakage is insufficient; above 300 bar, active ingredients degrade and particles agglomerate secondary.

[0007] Preferably, no surfactants, organic solvents, or crosslinking agents are added throughout the process, and only pure water is used as the dispersion medium.

[0008] The present invention has at least the following beneficial effects: it adopts a pure physical high-pressure homogenization modification process, with no chemical reagents added or residual pollution throughout the process, making it green and safe. The product can be directly used for the preparation of oral formulations, which is suitable for the safe medication needs of nuclear emergency populations.

[0009] This invention has at least the following beneficial effects: by precisely controlling parameters, the extract is transformed from micron to nanoscale while fully preserving the active functional groups of hydroxyl and carboxyl groups of Astragalus membranaceus, resulting in a significant increase in specific surface area and solving the problem of blocked active sites in traditional crude extracts. The present invention has at least the following beneficial effects: standardized and highly controllable process parameters, mild reaction conditions that do not damage the structure of active components, stable product performance, adaptability to large-scale industrial production, and meeting the needs of large-scale nuclear emergency material reserves.

[0010] The present invention has at least the following beneficial effects: the raw materials are conventional Chinese medicinal materials, which are widely available, inexpensive, and easy to store, and have extremely high industrialization and promotion value. Attached Figure Description

[0011] Figure 1 This is a flow chart of the high-pressure homogenization modified Astragalus membranaceus extract preparation process.

[0012] Figure 2 This is a comparison chart of the effect of homogenization pressure on the particle size and polydispersity index (PDI) of the product HP-ARE.

[0013] Figure 3 This is a particle size distribution diagram of the product HP-ARE under homogenization pressure.

[0014] Figure 4 This is a graph comparing the number of cycles with the particle size and polydispersity index (PDI) of the product HP-ARE.

[0015] Figure 5 This is a particle size distribution diagram of the product HP-ARE as a function of the number of cycles.

[0016] Figure 6 This is a graph comparing the concentration of the product HP-ARE with its particle size and polydispersity index (PDI).

[0017] Figure 7 This is a particle size distribution diagram of the product HP-ARE as a function of concentration.

[0018] Figure 8 The response surface and contour plots of HP-ARE particle size as a function of homogenization pressure, solution concentration, and number of homogenization cycles are shown. Detailed Implementation

[0019] The present invention will now be described in further detail with reference to the accompanying drawings, so that those skilled in the art can implement it based on the description.

[0020] It should be understood that terms such as “having,” “comprising,” and “including” as used herein do not exclude the presence or addition of one or more other elements or combinations thereof.

[0021] Example 1: An optimal standard process for the green preparation of high-pressure homogenized modified Astragalus extract adapted for nuclear emergency uranium euthanasia includes the following steps: S1. Take Astragalus membranaceus slices, pulverize them, and then perform multi-stage water extraction. The preferred material-to-liquid ratio is 1:10, 1:10, and 1:5. Extract three times at 80-95℃ for 1 h each time. Combine all the extract filtrates, concentrate under reduced pressure to a density of 1.13-1.18 g / mL, slowly add anhydrous ethanol to adjust the ethanol concentration to 70%, let stand for 24 h for alcohol precipitation, centrifuge at 5000 r / min for 10 min, collect the precipitate and vacuum dry to obtain micron-sized crude Astragalus membranaceus extract ARE. S2, weigh ARE powder, dissolve it in deionized water to prepare a homogeneous aqueous solution of 2.0 mg / mL, stir at room temperature for 2 h to fully disperse and eliminate particle agglomeration, and obtain a clear and stable precursor solution; S3, the precursor liquid is fed into a high-pressure homogenizer, the equipment is set to a constant temperature of 35 ℃, a homogenization pressure of 200 bar, material is circulated and homogenized 6 times, and a constant flow rate of 100 mL / min. Water is used as the dispersion medium throughout the process, and no chemical additives are added, thus completing the pure physical nano-modification. S4. The homogenized modified aqueous solution was placed in a low temperature environment of 4 ℃ and allowed to stand for 12 h. The ethanol concentration was adjusted to 70% again for secondary alcohol precipitation. The mixture was centrifuged at 5000 r / min for 10 min, the bottom precipitate was collected, and vacuum dried to finally obtain the nano-scale high-pressure homogenized modified Astragalus extract HP-ARE.

[0022] The HP-ARE particles prepared in this embodiment are uniformly dispersed, without obvious agglomeration, and have good stability, fully meeting the safety and performance requirements of emergency oral ovulation induction raw materials.

[0023] Comparative Example 1 (Control Group without Homogenization Modification): Unmodified micron-sized Astragalus membranaceus crude extract ARE was prepared directly using step S1 of this invention without high-pressure homogenization modification. The remaining purification and drying operations were completely consistent with Example 1. The results showed that the unmodified ARE particles were severely aggregated, had a small specific surface area, insufficient exposure of active functional groups, and a significantly lower ability to complex uranyl ions than the modified sample.

[0024] Comparative Example 2 (Low-Pressure Homogenization Control Group): The homogenization pressure was set to 50 bar, and the remaining process parameters and operating steps were the same as in Example 1. The results showed that the low-pressure shear force and cavitation effect were insufficient, which could not effectively break up micron-sized agglomerates. The product particle size was not uniform, the active sites were not fully exposed, and the improvement effect on uranium complexation performance was limited.

[0025] Comparative Example 3 (High-Pressure Over-Modification Control Group): The homogenization pressure was set to 600 bar, and the remaining process parameters and operating steps were the same as in Example 1. The results showed that ultra-high pressure induced secondary agglomeration of nanoparticles, verifying that 200 bar was the optimal modification pressure of the present invention.

[0026] Process validation results: Through multiple sets of parallel experiments, the process parameters defined in this invention have excellent stability and repeatability. Compared with low-pressure, high-pressure modified and unmodified samples, the HP-ARE prepared by the optimal process has a uniform structure, complete activity retention, and significantly improved uranium complexation potential. Moreover, the entire process is green and leaves no chemical residues, and can stably meet the needs of industrial mass production and nuclear emergency material reserves.

Claims

1. A green preparation process for high-pressure homogenized modified Astragalus extract adapted for nuclear emergency uranium euthanasia, characterized in that, Includes the following steps: S1, Preparation of crude extract of Astragalus membranaceus: Astragalus membranaceus slices were extracted by multi-stage constant temperature reflux with pure water, the filtrate was concentrated under reduced pressure, precipitated with alcohol to 70%, allowed to stand at 4 ℃ for 24 h to precipitate, the precipitate was collected and freeze-dried to obtain unmodified Astragalus membranaceus extract ARE; S2, preparation of homogeneous precursor solution: Dissolve ARE powder in deionized water to prepare a homogeneous aqueous solution of 1.95~2.05 mg / mL, and stir at room temperature until no solid agglomeration occurs; S3, High-pressure homogenization modification treatment: The homogenizer is kept at a constant temperature of 35 ℃, the homogenization pressure is controlled at 200 bar, the material is circulated and homogenized 6 times, and the flow rate is 100 mL / min; no surfactants or chemical crosslinking agents are added throughout the process. S4, spray drying: After homogenization, the aqueous solution was concentrated under reduced pressure, and anhydrous ethanol was added to adjust the concentration to 70%. The solution was allowed to stand at 4 ℃ to precipitate, centrifuged at 5000 r / min, and the precipitate was freeze-dried under vacuum to obtain nano-scale high-pressure homogenized Astragalus extract HP-ARE.

2. The preparation process according to claim 1, characterized in that, The extraction process in step S1 is to extract the material at a constant temperature of 80 ℃ for 1 h in three separate extractions with a material-to-liquid ratio of 1:10, 1:10, and 1:

5.

3. The preparation process according to claim 1, characterized in that, The homogenization pressure is limited to 50~600 bar, with only 200 bar being the optimal modification pressure. Excessive pressure can cause secondary agglomeration of particles and degradation of antioxidant activity.

4. The preparation process according to claim 1, characterized in that, In step S4, the centrifugation speed is 5000 r / min, the centrifugation time is 10 min, and the settling time is 12 h.

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