Preparation of radix astragali extract powder and application of radix astragali extract powder in nuclide excretion promotion and protection medicines

Abstract

The invention discloses preparation of radix astragali extract powder and application of the radix astragali extract powder in nuclide excretion promotion and protection drugs, and the preparation method comprises the following steps: crushing radix astragali decoction pieces into particles, and extracting to obtain a radix astragali extract I and a radix astragali extract II; and mixing and grinding the radix astragali extract I and the radix astragali extract II to obtain the radix astragali extract powder. The astragalus extract powder disclosed by the invention has double functions of promoting excretion and resisting radioactive injury, can promote the excretion of nuclides in a body, reduces the retention of the nuclides in blood, liver, kidney or lung, reduces active oxygen of oxidative stress rise in a living body caused by uranium, and improves the safety of the living body. Meanwhile, the reduced cell mitochondrial membrane potential caused by uranium in a living body is effectively improved, and the excellent damage repairing capacity is achieved; compared with a broad-spectrum discharge promoting agent EDTA-CaNa2, the radix astragali extract and the powder thereof have lower cytotoxicity and better discharge promoting and protecting effects, and have a good application prospect in nuclide discharge promoting and protecting.

Description

Technical Field

[0001] The present invention belongs to the technical field of nuclide processing, and more specifically, to the preparation of an astragalus extract powder and its application in nuclide stimulating and protective drugs. Background Art

[0002] Uranium is used in large quantities as an important raw material for the nuclear industry. Uranium has high biochemical toxicity and is radioactive. After entering the human body, uranium migrates in the human body environment and quickly accumulates in organs and tissues, which will cause serious harm to human health. Uranium and its compounds cause both chemical damage and radiation damage to the body. The most effective treatment method at present is chelation therapy, which is to take a drug that can efficiently chelate with radioactive nuclides to promote the excretion of nuclides. However, while chelating drugs accelerate the excretion of radioactive nuclides from the body, they also have toxic side effects on the body. Therefore, it is of great significance to develop drugs with low toxicity and high efficiency that promote the excretion of radioactive nuclides and reduce radiation damage.

[0003] Astragalus membranaceus (Fisch.) Bunge is a perennial herb in the genus Astragalus of the Leguminosae family. Astragalus has medicinal value. According to the Chinese Pharmacopoeia and the Chinese Materia Medica Dictionary, Astragalus has the effects of replenishing qi and raising yang, consolidating the exterior and stopping sweating, promoting diuresis and reducing swelling, promoting fluid and nourishing blood, relieving stagnation and relieving numbness, expelling toxins and expelling pus, and healing sores and promoting tissue regeneration. It is mainly used to treat all symptoms of qi deficiency and blood deficiency, and can be used to treat qi deficiency and fatigue, poor appetite and loose stools, sinking of qi in the middle, chronic diarrhea and prolapse of the anus, bloody stool and metrorrhagia, spontaneous sweating due to exterior deficiency, edema, internal heat and thirst, sallow complexion due to blood deficiency, hemiplegia, pain and numbness, carbuncle and carbuncle that are difficult to ulcerate, long-term ulceration that does not heal, and cough due to lung deficiency. However, there are few studies on the use of Astragalus extracts in radionuclide excretion promotion and anti-radiation damage. Summary of the invention

[0004] An object of the present invention is to solve at least the above problems and / or disadvantages and to provide at least the advantages which will be described hereinafter.

[0005] In order to achieve these purposes and other advantages of the present invention, a method for preparing an astragalus extract powder is provided, comprising the following steps:

[0006] Step 1: Take the slices of Astragalus, crush them into particles, soak them in water, continue to add water, heat and heat to perform the first extraction, filter, set aside the filtrate, add water again, heat and heat to perform the second extraction, filter, combine the filtrate, concentrate under reduced pressure, cool to room temperature, then add 95% ethanol, leave at room temperature, and collect the precipitate;

[0007] Step 2, adding an equal amount of water to the precipitate obtained in step 1, stirring while adding, after the precipitate is dissolved, adding 95% ethanol, stirring evenly, precipitating with alcohol, collecting the precipitate and the supernatant respectively, and drying the precipitate to obtain Astragalus extract I;

[0008] Step 3, adding 95% ethanol to the supernatant obtained in step 2, stirring evenly, precipitating with alcohol, collecting the precipitate, and drying to obtain Astragalus extract II;

[0009] Step 4: Mix and grind the Astragalus extract I obtained in step 2 and the Astragalus extract II obtained in step 3 to obtain an Astragalus extract powder.

[0010] Preferably, in step 1, the soaking in water specifically comprises: adding water 2 to 4 times the mass of the astragalus and soaking for 1 to 2 hours; and continuing to add water so that the total mass of the water is 8 to 12 times the mass of the astragalus.

[0011] Preferably, in step 1, the extraction temperature of the first extraction and the second extraction are both 90-100° C., and the extraction time is both 1-3 hours.

[0012] Preferably, in the step 1, the reduced pressure is used for concentration to a density of 1.11 to 1.19.

[0013] Preferably, in step 1, 95% ethanol is added to make the ethanol content 70%; and the mixture is left at room temperature for 20 to 28 hours.

[0014] Preferably, in the step 2, 95% ethanol is added to make the ethanol content 35%; and the alcohol precipitation is carried out for 20 to 28 hours.

[0015] Preferably, in the step three, 95% ethanol is added to make the ethanol content 70%; and the alcohol precipitation is carried out for 20 to 28 hours.

[0016] In order to further enhance the ovulation-promoting effect of the Astragalus extract powder, the Astragalus extract powder prepared by the above preparation method was treated as follows: the Astragalus extract powder was placed in a low-temperature corona irradiation device for 20 to 40 minutes, the treatment atmosphere was air, the temperature was 15 to 30°C, the voltage was 6 to 10 KV, and the distance was 2 to 5 cm; the irradiated Astragalus extract powder and distilled water were mixed at a mass volume ratio of 1g:150 to 300mL, stirred and dissolved to obtain solution A; sodium polyphosphate and trimetaphosphoric acid were added. The obtained mixed phosphate was mixed with distilled water at a mass volume ratio of 1g:10-50mL, and the mixture was stirred to dissolve to obtain solution B; according to the mass ratio of astragalus extract powder and mixed phosphate of 1:10-20, solution A and solution B were evenly mixed, 0.1mol / L NaOH solution was added to adjust the pH to 7.5-8.5, and the mixture was reacted in a constant temperature water bath at 70-80°C for 2-4h. After the reaction was completed, the mixture was dialyzed with distilled water for 72h and freeze-dried to obtain modified astragalus extract powder.

[0017] An application of the astragalus extract powder prepared by the preparation method as described above in the preparation of radionuclide ovulation promoting and protective drugs.

[0018] Preferably, the nuclide is uranium.

[0019] Preferably, the use of the astragalus extract powder in the preparation of radionuclide stimulating and protective drugs includes at least one of the following specific uses:

[0020] (1) Promote the excretion of radionuclides with feces and urine;

[0021] (2) Reduce the retention of radionuclides in the blood, liver, kidneys, or lungs;

[0022] (3) reduce ROS caused by radionuclides in vivo, which increases oxidative stress;

[0023] (4) Improve the mitochondrial membrane potential of cells in the body that is reduced by radionuclides.

[0024] The present invention includes at least the following beneficial effects: the present invention prepares an Astragalus extract and an Astragalus extract powder, which have the dual functions of promoting excretion and resisting radiation damage, can promote the excretion of nuclides in the body, reduce the retention of nuclides in the blood, liver, kidneys or lungs, effectively reduce the reactive oxygen species increased by oxidative stress in the body caused by uranium, and effectively improve the reduced cell mitochondrial membrane potential in the body caused by uranium, and have excellent damage repair ability; compared with the broad-spectrum excretion promoter EDTA-CaNa2, the Astragalus extract and the powder of the present invention have lower cytotoxicity and better excretion promotion and protection effects, and have good application prospects in nuclide excretion promotion and protection.

[0025] Other advantages, objectives and features of the present invention will be embodied in part through the following description, and in part will be understood by those skilled in the art through study and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 The infrared spectra of Astragalus extract I and Astragalus extract II prepared in Example 1 of the present invention;

[0027] Figure 2 SEM images of Astragalus extract I (a) and Astragalus extract II (b) prepared in Example 1 of the present invention;

[0028] Figure 3 It is the retention time curve diagram of Astragalus extract in GPC analysis;

[0029] Figure 4 GC-MS spectra of Astragalus extract I and Astragalus extract II prepared in Example 1 of the present invention;

[0030] Figure 5The effects of the astragalus extract and astragalus extract powder prepared in Example 1 of the present invention and EDTA-CaNa2 on the induced ovulation of IEC-6 cells, wherein a is a dosing concentration of 175 μg / mL, b is a dosing concentration of 550 μg / mL, *: indicates comparison with the negative control group, **: P < 0.01, ***: P < 0.001;

[0031] Figure 6 The excretion rate of uranium in mice with different U poisoning concentrations by the Astragalus extract and Astragalus extract powder prepared in Example 1 of the present invention and EDTA-CaNa2, wherein a: the poisoning dose is 2.96 μmol 238 U / kg; b: The toxic dose is 9.24 μmol 238 U / kg; c: The toxic dose is 16.64 μmol 238 U / kg; *: compared with the negative control group, **: P < 0.01, **: P < 0.001; #: compared with the EDTA-CaNa2 group, ##: P < 0.01, ###: P < 0.001; ns: no significant difference;

[0032] Figure 7 The astragalus extract and astragalus extract powder prepared in Example 1 of the present invention, EDTA-CaNa2, and the concentration of U poisoning were 2.96 μmol 238 U / kg of uranium in the liver (a), lung (b), kidney (c) and blood (d) of mice, where *: indicates comparison with the negative control group, **: P < 0.01;

[0033] Figure 8 The astragalus extract and astragalus extract powder prepared in Example 1 of the present invention, EDTA-CaNa2, and the U poisoning concentration were 9.24 μmol 238 U / kg of uranium in the liver (a), lung (b), kidney (c) and blood (d) of mice, where *: indicates comparison with the negative control group, **: P < 0.01;

[0034] Fig. 9 The effect of uranium on the survival rate of IEC-6 cells;

[0035] Fig.10 The effects of the astragalus extract and astragalus extract powder and EDTA-CaNa2 prepared in Example 1 of the present invention on the survival rate of IEC-6 cells, wherein a: cytotoxicity curves of astragalus extract and EDTA-CaNa2; b: cytotoxicity curve of astragalus extract powder;

[0036] Fig.11The comprehensive effects of the astragalus extract and astragalus extract powder prepared in Example 1 of the present invention, EDTA-CaNa2 and uranyl nitrate on the survival rate of IEC-6 cells;

[0037] Fig.12 The astragalus extract prepared in Example 1 of the present invention and the statistical graph of the intracellular reactive oxygen species level and fluorescence intensity of IEC-6 cells after EDTA-CaNa2 treatment;

[0038] Fig.13 The diagram of the mitochondrial membrane potential level of IEC-6 cells after the astragalus extract prepared in Example 1 of the present invention and EDTA-CaNa2 treatment;

[0039] Fig.14 This is a statistical graph of the fluorescence intensity of mitochondrial membrane potential of IEC-6 cells after the astragalus extract prepared in Example 1 of the present invention and EDTA-CaNa2 treatment;

[0040] Fig.15 The graph of the level of reactive oxygen species in NRK-52E cells after the astragalus extract prepared in Example 1 of the present invention and EDTA-CaNa2 treatment;

[0041] Fig.16 The statistical graph of the fluorescence intensity of reactive oxygen species in NRK-52E cells after the astragalus extract prepared in Example 1 of the present invention and EDTA-CaNa2 treatment;

[0042] Fig.17 Statistical graphs of mitochondrial membrane potential level and fluorescence intensity of NRK-52E cells after the Astragalus extract prepared in Example 1 of the present invention and EDTA-CaNa2 treatment. DETAILED DESCRIPTION

[0043] The present invention is further described in detail below in conjunction with the accompanying drawings so that those skilled in the art can implement the invention with reference to the description.

[0044] It should be understood that terms such as “having”, “including” and “comprising” used herein do not exclude the existence or addition of one or more other elements or combinations thereof.

[0045] Example 1

[0046] A method for preparing an astragalus extract powder comprises the following steps:

[0047] Step 1, take the astragalus slices, crush them into particles, place them in a multifunctional extraction, concentration and recovery device, add 3 times the weight of water and soak them for 1.5 hours, continue to add water to make the total mass of water added 10 times the mass of the astragalus particles, heat them with water vapor to 90°C, maintain the extraction temperature at 90-100°C, extract for 2 hours, filter, and set aside the filtrate, add 10 times the mass of the astragalus particles to the residue again, continue to heat the water vapor to 90°C, maintain the extraction temperature at 90-100°C, extract again for 2 hours, filter, combine the filtrate, filter, and concentrate the filtrate under reduced pressure, cool the concentrate to room temperature to a density of 1.15, then add 95% ethanol to make the ethanol content in the concentrate reach 70%, leave it at room temperature for 24 hours, and collect the precipitate;

[0048] Step 2: add water of equal weight to the precipitate obtained in step 1, stir while adding, and after the precipitate is fully dissolved, add 95% ethanol to make the ethanol content in the dissolved material 35%, stir evenly, and precipitate with alcohol for 24 hours, collect the precipitate and the supernatant respectively, and dry the precipitate to obtain Astragalus extract I (ASP I);

[0049] Step 3: Add 95% ethanol to the supernatant obtained in step 2 to make the ethanol content 70%, stir while adding, and precipitate with alcohol for 24 hours, remove the supernatant, collect the precipitate, and dry it to obtain Astragalus extract II

[0050] (ASPⅡ);

[0051] Step 4. Grind ASPⅠ obtained in step 2 and ASPⅡ obtained in step 3 thoroughly by ball mill. To ensure the accurate content of the prepared powder, stir the powder by mixing drum and mix the powder by equal incremental mixing method. Grind the two components of the astragalus extract by grinding method vigorously and persistently to make the components fully mixed in the powder to obtain the dual-function astragalus extract powder (ASP powder) of nuclide promotion and anti-radiation damage. Take an appropriate amount of astragalus extract powder on smooth paper, flatten its surface, observe it in a bright place, and check the quality of the powder. The product has uniform color and no patterns or spots. Pass the astragalus extract powder through an automatic packaging machine and store it in aluminum-plated light-proof packaging bags to delay moisture absorption and oxidation of the astragalus extract powder.

[0052] 1. Performance test of Astragalus extract

[0053] (1) Infrared analysis

[0054] Analysis method: The sample powder was prepared by potassium bromide disc pressing method and the infrared spectrum was obtained by scanning on Nicolet 6700 FT-IR spectrometer (Thermo Scientific Instrument) with a scanning range of 400-4000 cm -1 , resolution 4cm -1 , the test results are as follows Figure 1 shown.

[0055] from Figure 1 It can be seen that the ASPⅠ of Astragalus extract is at 3378cm -1 There is a strong broadband at 2931cm -1 The peak at 1629 cm is characteristic of CH stretching vibration in CH2 group; -1 The band at 1411 cm is the characteristic peak of C=O stretching vibration, which indicates that ASPⅠ contains uronic acid. -1 There are symmetrical deformation vibration and asymmetrical bending of methyl at 1024cm -1 The strong absorption peak at 577 cm indicates the stretching vibration of the α-pyranose ring in the glycosyl residue; -1 The absorption peak at 1629 cm indicates the existence of C-CO-C vibration. -1 The peak at 1287 cm is the C=O stretching vibration. -1 There is an absorption peak at 1026cm, which is the stretching vibration structure of the carbon-oxygen-carbon bond of ether; -1 The absorption peak at indicates the presence of an asymmetric vibration peak of COC and the stretching vibration of the α-pyranose ring in the sugar residue.

[0056] (2) Scanning electron microscope test

[0057] Analytical method: The astragalus extract was fixed on the sample holder with the help of double-sided carbon tape and sputtered with gold for 180 s using an ion sputtering system (SC7620, Emitech, Great Britain) in vacuum, and then the morphological characteristics of the astragalus extract were examined using a scanning electron microscope (EVO 18, Zeiss, Germany). The test results are shown in Figure 2. Figure 2 As shown, a is ASPⅠ and b is ASPⅡ.

[0058] (3) Molecular weight analysis

[0059] Analytical method: Take an appropriate amount of astragalus extract sample and disperse it in 10mL of mixed eluent containing 0.01% NaNO3 and 0.02% NaN3, filter it through a 0.45μm microporous filter membrane, and use gel permeation chromatography (Agilent 1200, Agilent, USA) to determine the molecular weight. The test conditions are as follows: chromatographic column: SEC Start-up Kit (300mm×7.5mm); wavelength: 658nm; flow rate: 1.0mL / min; refractive index increment (dn / dc): 0.135.

[0060] The molecular weight of polysaccharides is closely related to their properties. The polarity and biological activity of polysaccharides are affected by their molecular weight. Figure 3 As shown in Figure 2, the weight average molecular weight of Astragalus extract was measured by gel permeation chromatography, and the weight average molecular weight of ASPⅠ was 1.48×10 5 g / mol, polydispersity index M W / Mn is 17.84, indicating that the molecular weight distribution of ASPⅠ is relatively dispersed. The weight average molecular weight of ASPⅡ is 3.27×10 4 g / mol, polydispersity index M W / Mn is 1.90, and the molecular weight is relatively concentrated.

[0061] (4) Monosaccharide composition analysis

[0062] Analytical method: The monosaccharide composition in Astragalus extract was determined by the sugar nitrile acetate derivatization method. The operation was as follows: first, the Astragalus extract (about 5 mg) was added to 3 mL of 2 mol / L trifluoroacetic acid (TFA) solution and hydrolyzed in an oil bath at 120 ° C for 2 h. The hydrolyzate was concentrated under reduced pressure, and then methanol was added and concentrated under reduced pressure and vacuum at less than 40 ° C until the trifluoroacetic acid was completely removed. Next, pyridine (2 mL), hydroxylamine hydrochloride (10 mg) and inositol (3 mg) were added and heated in a 90 ° C water bath for 30 min. After the water bath ended, the sample solution was taken out and cooled to room temperature, 1 mL of acetic anhydride was added and continued to be in a 90 ° C water bath for 30 min, and then the solvent was removed by reduced pressure and vacuum concentration. Finally, 2 mL of chloroform was added to re-dissolve the derivatized sample and filtered through a 0.45 μm microporous filter membrane and analyzed by gas chromatography-mass spectrometry (GC-MS) (Varian 3900GC-Saturn 2000, Varian, USA). The monosaccharide standard was used as a reference and inositol was used as an internal standard. The analysis conditions of the gas chromatograph (GC) and mass spectrometer (MS) are shown in Table 1.

[0063] Table 1

[0064]

[0065] The results of the analysis of monosaccharide composition in Astragalus extract by sugar nitrile acetate derivatization are as follows: Figure 4 As shown in the figure, ASPⅠ is composed of arabinose, fructose, mannose, glucose and galactose. ASPⅡ is composed of fructose, glucuronic acid, mannose, glucose and galactose.

[0066] 2. Uses of Astragalus Extract Powder

[0067] (1) Cell proliferation-promoting effects of Astragalus extract and Astragalus extract powder

[0068] Analysis method: IEC-6 cells in the logarithmic growth phase were collected and analyzed at a rate of approximately 2×105 The cells were inoculated at a density of 100 μg / well in a 6-well culture plate and cultured at 37°C and 5% CO2 for 12 h until the cells adhered to the wall. The culture medium was then removed and 2.0 mL of culture medium containing 903 μM uranyl and 175 μg / mL or 550 μg / mL of Astragalus extract (or ASP powder) prepared from the culture medium was added. Only 2.0 mL of culture medium containing 903 μM uranyl was added to the negative control group. EDTA-CaNa2 was set as the positive control. Three parallel experiments were set up for each group of experiments. After administration, the cells were cultured in a carbon dioxide incubator for 24 h. The original culture medium was discarded and 1 mL of PBS was added to each well to rinse the plate. The rinse was repeated twice. Then 0.5 mL of 0.25% trypsin was added to the plate and the plate was kept warm in a 37°C carbon dioxide incubator for 2 min. When the cells were observed to be "round and bright" under a microscope, 1 mL of complete culture medium was added. The cells were gently blown and the cell suspension was collected, counted, digested, and the uranium content was determined by ICP-MS. The measured data was converted into U(VI) content of ng / 10 6 cells.

[0069] The cells were cultured in complete medium and the concentration of uranyl nitrate was 903 μM. The uranium content in the cells was as follows: Figure 5 As shown, a is the dosing concentration of 175 μg / mL, and b is the dosing concentration of 550 μg / mL. Negative control group 10 6 Each cell contained 11242.8±618.0ng of uranium. When the drug concentration was 175μg / mL, every 10 6 The uranium content of each cell was 9043.8±542.1ng, 2256.6±498.0ng, 5354.1±23.1ng and 3878.9±134.4ng, respectively. Calculation showed that ASP powder could effectively remove 64.5%±1.2% of the uranium in the cells, while ASPⅠ, ASPⅡ and EDTA-CaNa2 could remove 80.0%±3.4%, 52.3%±2.5% and 19.3%±8.6% of the uranium in the cells, respectively. When the drug concentration was 550μg / mL, the EDTA-CaNa2 group, ASPⅠ group, ASPⅡ group and ASP powder group had no significant difference in uranium content per 10 6The uranium content of each cell was 6301.4±618.0ng, 4269.6±1336.5ng, 4770.5±481.6ng and 3658.4±228.0ng respectively. Calculation showed that ASP powder could effectively remove 66.5%±2.1% of uranium in cells, and ASPⅠ, ASPⅡ and EDTA-CaNa2 removed 61.6%±13.6%, 57.6%±2.4% and 44.0%±4.5% of uranium in cells respectively. At a higher dosage, ASP powder had a better effect of preventing cells from taking up uranium and promoting the excretion of uranium in cells.

[0070] (2) Effect of Astragalus Extract and Astragalus Extract Powder on Promoting Ovarian Function in Mice

[0071] Study on the effect of promoting ovulation in mice exposed to different uranium doses:

[0072] Analytical method: The uranyl poisoning doses for mice were 2.96μmol / kg, 9.24μmol / kg, and 16.64μmol / kg, respectively. The model control group was only given the same volume of saline; the mice in the negative control group were given 0.2mL of uranyl solution of different concentrations, and no medication was given; the mice in the experimental group were given 0.2mL of uranyl solution for 15 minutes, and then gavaged with 0.25g / mL of ASPⅠ, ASPⅡ, and ASP powder, respectively. The volume of each mouse was 0.4mL, and the same dose of EDTA-CaNa2 was used as the positive control. The mice were fasted but not watered for 12 hours before the poisoning. After the administration, the mice were given normal food and water. The administration was continued for three days, once every 24 hours, and feces and urine were collected every day. The collected mouse feces were dried at 105℃, and the feces weight was recorded after drying to constant weight, and the feces were crushed for digestion. 24 hours after the last administration, blood was collected from the eyeballs, the mice were killed, and the kidneys, livers, lungs, hearts and other tissues were taken to record the weight of each organ. The uranium content of blood, kidney, liver, lung and other organs, urine and feces was determined by ICP-MS after microwave digestion. Figure 6 shown.

[0073] from Figure 6 a It can be seen that when the poisoning dose is 2.96μmol 238 U / kg, the uranium excretion rate in feces and urine of negative control group was 25.75±3.41%, that of EDTA-CaNa2 group was 49.84±2.80%, that of ASPⅠ group was 51.21±3.80%, that of ASPⅡ group was 56.39±2.39%, and that of ASP powder was 87.14±3.02%; ASPⅠ and ASPⅡ were better than EDTA-CaNa2 in uranium excretion, and the uranium excretion rate of mice in ASP powder group was better than that of ASPⅠ, ASPⅡ and EDTA-CaNa2;

[0074] Figure 6 b is when the exposure dose is 9.24 μmol 238 U / kg, the uranium excretion rate in the feces and urine of the negative control group was 25.14±5.80%, the excretion rate in the EDTA-CaNa2 group was 30.49±4.87%, the excretion rates of ASPⅠ, ASPⅡ and ASP powder were 47.78±2.03%, 68.77±5.09% and 86.50±8.71% respectively. Compared with the negative control group, the excretion rate of the mice in the ASP powder group was significantly increased (P<0.01), and the uranium excretion rate in the mice in the ASP powder group was significantly higher than that in the EDTA-CaNa2 group.

[0075] When the exposure dose was 16.64 μmol 238 U / kg The uranium excretion rate in mice is as follows Figure 6 As shown in c, the uranium excretion rate in feces and urine of the negative control group was 45.71±2.27%, the excretion rate in the EDTA-CaNa2 group was 64.71±4.56%, and the excretion rates of ASPⅠ, ASPⅡ and ASP powder were 52.53±3.68%, 79.77±0.68% and 90.93±3.41% respectively; compared with the EDTA-CaNa2 group, the uranium excretion rate of ASP powder in mice was significantly higher than that of EDTA-CaNa2;

[0076] In general, ASP powder has a better excretion-promoting effect on uranium contamination in the digestive tract of mice than the broad-spectrum excretion-promoting agent EDTA-CaNa2, and is also better than ASPⅠ and ASPⅡ. ASP powder has a better excretion-promoting effect.

[0077] The exposure dose was 2.96 μmol 238 U / kg, the amount of uranium in each organ of the mouse is as follows Figure 7 The amount of uranium in the liver is as shown. Figure 7 As shown in a, the uranium content in the liver of the EDTA-CaNa2 group was significantly higher than that of the negative control and test groups. The uranium content in the liver of the EDTA-CaNa2 group was 27.50±2.44μg / g, while the uranium content in the liver of the ASPⅠ, ASPⅡ and ASP powder groups was 5.23±2.33μg / g, 4.37±0.80μg / g and 2.57±0.90μg / g, respectively, which was significantly lower than that of the EDTA-CaNa2 group. The uranium content in the liver of the EDTA-CaNa2 group mice was not only not reduced but increased compared with the negative control group. The reason may be that the metabolism of the drug changes the metabolic rate of uranium, causing the redistribution of uranium in biological tissues, which increases the uranium content in the liver. The uranium content in the lungs is as follows: Figure 7As shown in b, the uranium content in the lungs of mice in the negative control group and EDTA-CaNa2 group was 8.56±1.25μg / g tissue and 4.55±1.41μg / g tissue, respectively; the uranium content in the lungs of the ASPⅡ group was 4.22±1.02μg / g tissue, and the uranium content in the lungs of the ASP powder group was 3.22±1.75μg / g tissue. The uranium content in the lungs of mice in the ASP powder group was significantly different from that in the negative control group (P<0.05). ASP powder promoted the excretion of 62.32±20.44% of uranium in the lungs, and the excretion rate of the EDTA-CaNa2 group was 46.83±16.54% compared with the negative control group. This shows that ASP powder has a certain excretion effect on uranium deposited in the lungs in vivo. Figure 7 As shown in c, the U content in the kidneys of mice in the ASP powder group was significantly lower than that in the negative control group and the EDTA-CaNa2 group. Compared with the negative control group, it could promote the excretion of 71.02±8.78% of uranium in the kidneys.

[0078] like Figure 7 As shown in Figure d, after treatment with Astragalus extract and EDTA-CaNa2, trace amounts of uranium remained in the blood of mice. The uranium content in the blood of the negative control group was 1.25±0.30μg / g, and the uranium content in the blood of mice in the EDTA-CaNa2 group, ASPⅠ group, ASPⅡ group and ASP powder group was 0.02±0.00μg / g, 0.21±0.03μg / g, 0.63±0.17μg / g and 0.33±0.06μg / g, respectively. The blood excretion rate of EDTA-CaNa2 reached 98.51±0.14%, which greatly reduced the content of uranium in the blood. The blood excretion rate of the ASP powder group was 71.97±0.09%, which reduced the content of uranium in the blood. In summary, both EDTA-CaNa2 and ASP powder can prevent the absorption of uranium into the blood or promote its distribution and excretion to a certain extent, but EDTA-CaNa2 has a greater biological toxicity.

[0079] The exposure dose was 9.24 μmol 238 U / kg, the uranium content in each organ of the mouse is as follows Figure 8 As shown, the liver (a), lung (b), kidney (c) and blood (d). The uranium content in the liver of the ASP powder group reached 9.47±2.42μg / g, which was higher than that of the negative control group. At a certain dosage concentration, the drug's effect on promoting uranium excretion was weakened by increasing the toxic concentration. The uranium content in the lungs of the negative control group and the EDTA-CaNa2 group of mice was 4.28±0.70 and 7.84±0.80μg / g, respectively. The uranium content in the lungs was significantly higher than that of the negative control group, while the comparative toxic dose was 2.96μmol 238U / kg, the uranium exposure dose increased, and the rate of uranium excretion from the mouse lungs by the test drug decreased; the uranium content in the lungs of mice in the ASPⅡ group was 3.49±0.85μg / g, and the ASP powder had no obvious effect on the excretion of uranium deposited in the mouse lungs at this exposure dose. Compared with the negative control group, the rate of uranium excretion in the kidneys of the ASP powder group was 57.68±14.24%, which shows that Astragalus extract has a certain ability to promote the excretion of uranium in the kidneys. The uranium content per gram of blood samples in the negative control, EDTA-CaNa2 and ASP powder groups was 0.74±0.13μg, 0.45±0.10μg and 0.32±0.11μg, respectively. The residual uranium in the blood was still small, which shows that blood is not the main place for uranium distribution in organisms.

[0080] (3) Effects of Astragalus extract and Astragalus extract powder on radiation damage

[0081] Uranium cytotoxicity to IEC-6 cells:

[0082] Rat small intestinal epithelial cells (IEC-6 cells) in logarithmic growth phase were cultured at 5×10 3 The cells were evenly inoculated in a 96-well plate and cultured at 37°C and 5% CO2 for 12 hours. The test was performed after the cells adhered to the wall. The original culture medium of the 96-well plate was removed, and culture medium containing different concentrations of uranium (the concentration was set to 12, 20, 50, 100, 199, 398, 797, 1195, and 1594 μM) was added to each group of 6 replicate wells. The culture medium without uranium was used as a control. After culturing in an incubator at 37°C and 5% CO2 for 24 hours, 10 μL of CCK-8 solution was added and cultured for another 2 hours. The absorbance value A was measured at a wavelength of 450 nm using an enzyme reader, and the cell survival rate was calculated as follows:

[0083]

[0084] The results of the cytotoxicity test of uranium on IEC-6 cells are as follows Fig. 9 As shown in Figure 2, as the concentration of uranyl nitrate increased, the cell survival rate decreased. When the concentration of uranyl nitrate was 797 μM, the cell survival rate was 58.5 ± 4.0%. The half-maximal inhibitory concentration was calculated by Graphpad and the IC 50 The value is 903μM. Because cells are more sensitive to drug stimulation at the half inhibitory concentration, the cell mortality rate caused by uranyl is at a medium level. If the cell mortality rate is too high, too few cells will be collected in the ovulation promotion test, and the accuracy of the ovulation promotion test data cannot be ensured. Therefore, 903μM was selected as the concentration for the comprehensive toxicity and cell ovulation promotion test.

[0085] Cytotoxicity study of Astragalus extract and ASP powder:

[0086] Rat small intestinal epithelial cells (IEC-6 cells) in the logarithmic growth phase were seeded in a 96-well plate, with 5×10 3 Cells were cultured at 37°C and 5% CO2 for 12 hours, and the test was performed after the cells attached to the wall. The original culture medium was removed, and the culture medium was replaced with a culture medium containing different concentrations of astragalus extract, ASP powder or EDTA-CaNa2 for 24 hours (drug concentrations were 5.5, 17.5, 55, 175, 550, 1750, 5000 μg / mL), with 6 replicates per group, and cultured in an incubator at 37°C and 5% CO2 for 24 hours. After culture, 10 μL of CCK-8 solution was added, and culture was continued for 2 hours. The absorbance value A was measured at a wavelength of 450 nm by an enzyme marker, and the cell survival rate was calculated according to Formula 1.

[0087] like Fig.10As shown in the figure, a is the cytotoxicity curve of Astragalus extract and EDTA-CaNa2; b is the cytotoxicity curve of ASP powder. With the increase of drug concentration, cell survival first remained at a certain value and then decreased. Astragalus extract has the characteristics of low cytotoxicity compared with EDTA-CaNa2. When the drug concentration is in the range of 250-750μg / mL, ASPⅡ shows a certain effect of promoting cell growth. When the concentration of ASPⅡ is 250μg / mL, the cell survival rate is 128.3%±10.2%, while the cell survival rate of EDTA-CaNa2 group is only 44.8%±5.8%. When the drug concentration was 750μg / mL, the cell survival rates of ASPⅠ and ASPⅡ were 103.4%±9.1% and 110.9%±7.9%, respectively; when the drug concentration was 250-1000μg / mL, both ASPⅠ and ASPⅡ had good biocompatibility and were almost non-toxic to cells. However, under the same conditions, the cell survival rate of EDTA-CaNa2 was less than 50%, which caused serious damage to the small intestinal epithelial cells. The toxicity of EDTA-CaNa2 was significantly higher than that of Astragalus extract. From the perspective of cytotoxicity, Astragalus extract is a substance with low cytotoxicity. In the range of 250-750μg / mL, ASPⅡ did not show cytotoxicity and showed cell proliferation effect, so ASPⅡ had good biocompatibility. As the drug concentration increased, the cell survival of ASP powder first remained at a certain value and then decreased. Compared with EDTA-CaNa2, ASP powder has the characteristics of low cytotoxicity. When the drug concentration was within the range of 5.5-550 μg / mL, the cells treated with ASP powder showed no cytotoxic effect. When the ASP powder concentration was 5.5 μg / mL, the cell survival rate was 102.7%±7.5%. When the drug concentration was 550 μg / mL, the cell survival rate after the ASP powder treatment was 101.9%±3.4%. When the ASP powder concentration was between 5.5-1750 μg / mL, it had good biocompatibility and was almost non-toxic to cells. However, under the same culture conditions, when the EDTA-CaNa2 concentration was 550 μg / mL, the cell survival rate was less than 50%, causing serious damage to the small intestinal epithelial cells. The toxicity of EDTA-CaNa2 was significantly higher than that of the Astragalus extract powder. From the aspect of cytotoxicity, it was shown that the Astragalus extract powder was a substance with low cytotoxicity.

[0088] Astragalus extract and ASP powder and uranyl comprehensive toxicity:

[0089] IEC-6 cells in logarithmic growth phase were cultured at 5×10 3Each well was inoculated on a 96-well culture plate and cultured at 37°C and 5% CO2 for 12 hours. The test was performed after the cells adhered to the wall. The original culture medium was removed, and complete culture medium was used to prepare uranyl nitrate and astragalus extract or ASP powder, respectively. The uranyl concentration was 903 μM, and the drug concentration was 5.5, 17.5, 55, 175, 550, 1750 and 5000 μg / mL. Six replicate wells were set for each concentration group, and they were placed in an incubator at 37°C and 5% CO2 for 24 hours. The absorbance A was measured at a wavelength of 450nm using a microplate reader using the CCK-8 method, and the cell survival rate was calculated according to formula 1.

[0090] The results of the comprehensive cytotoxicity test of Astragalus extract and ASP powder with uranyl are as follows Fig.11 As shown in the figure. The cell survival rate of the combined toxicity of ASPⅡ and uranyl slowly decreased after the concentration of ASPⅡ reached 55μg / mL, and dropped sharply when the concentration reached 550μg / mL. Considering the effect of uranyl on cell activity, ASPⅡ had a certain therapeutic effect on the cytotoxicity caused by uranyl at 5.5-550μg / mL, and acted on cells with uranyl toxicity at higher concentrations. After 550μg / mL, Astragalus extract and uranyl showed cytotoxicity together, and the cell survival rate decreased. At 5.5-550μg / mL, the highest cell survival rate of ASPⅡ was 117.1±8.5%, while the highest cell survival rate of ASPⅠ was 94.1±9.9%. ASPⅡ was better than ASPⅠ in alleviating uranium-induced cell death, and its combined toxicity with uranyl was less than that of ASPⅠ and uranyl before 1750μg / mL. When the concentration of ASPⅠ reached 1750μg / mL, the cell survival rate could still reach 68.5%±8.7%, and then the cell survival rate dropped sharply with the increase of concentration. The combined toxicity of ASP powder and uranyl was less than that of uranyl alone at the same concentration, and the cell survival rate showed a certain concentration dependence. When the uranyl concentration remained unchanged, the cell survival rate showed a trend of first decreasing, then increasing, and then decreasing as the ASP powder concentration increased. When the ASP powder concentration was 55 μg / mL, the cell survival rate was 54.1% ± 8.3%; when the ASP powder concentration was 550 μg / mL, the cell survival rate was 106.9% ± 7.1%, reaching the highest value, and then decreased again. When the uranyl nitrate concentration was 903 μM, the cell survival rate of ASP powder was 550 μg / mL. ASP powder had a good therapeutic effect on cell death caused by uranyl nitrate at this concentration, and subsequent studies were conducted at this concentration.

[0091] Study on the protective effect of Astragalus extract on oxidative stress of IEC-6 cells induced by uranyl nitrate:

[0092] Analysis method: IEC-6 cells in the logarithmic growth phase were collected and analyzed at a rate of approximately 2×10 5The cells were inoculated at a density of 100 / well in a 6-well culture plate and cultured at 37°C and 5% CO2 for 12 hours. The culture medium was then removed and 2.0 mL of culture medium containing 903 μM uranyl and 550 μg / mL Astragalus extract (ASPⅠ, ASPⅡ) or EDTA-CaNa2 was added. Only 2.0 mL of 903 μM uranyl was added to the control group. After administration, the cells were cultured in a carbon dioxide incubator (37°C, 5% CO2) for 24 hours. The culture medium was collected by aspiration and 1 mL of PBS was added to each well to rinse the plate. The original culture medium in the 6-well plate was removed and 1 mL of PBS was added to each well to gently rinse the plate. 1 mL of serum-free culture medium and 1 μL of DCFH-DA were added and incubated in a carbon dioxide incubator in the dark for 30 minutes. After the incubation, the original culture medium was removed by aspiration and the cells were washed twice with serum-free culture medium. The fluorescence intensity was observed under a fluorescence microscope.

[0093] When the uranyl nitrate poisoning concentration was 903 μM and the drug administration concentration was 550 μg / mL, the level of reactive oxygen species and fluorescence intensity in IEC-6 cells were as follows: Fig.12 As shown in the figure, the DCFH-DA probe detects the level of intracellular reactive oxygen species. The higher the level of intracellular oxidative stress, the stronger the fluorescence intensity. It was observed that the fluorescence level of cells treated with Astragalus extract was significantly lower than that of the uranyl treatment group, indicating that the level of reactive oxygen species in ASPⅠ and ASPⅡ cells was lower than that in the uranyl control group, indicating that Astragalus extract can effectively prevent uranyl from causing oxidative damage to IEC-6 cells or has a certain therapeutic effect on uranium-induced cell oxidative damage. The fluorescence intensity of the cells in the EDTA-CaNa2 group was lower, but the number of cells decreased and the cells shrank from the bright field of the microscope. The morphology of some cells changed from round to long spindle with some tentacles. The reason may be that the combined toxicity of uranyl and EDTA-CaNa2 is more toxic to cells, the cells die, and the survival of living cells decreases, so the fluorescence intensity of reactive oxygen species detected is weaker than that of other experimental groups.

[0094] Study on the protective effect of Astragalus extract on mitochondrial membrane potential of IEC-6 cells oxidized by uranyl nitrate:

[0095] Analysis method: IEC-6 cells in the logarithmic growth phase were collected and analyzed at a rate of approximately 2×10 6 The cells were inoculated at a density of 100 / well in a 6-well culture plate and cultured at 37°C and 5% CO2 for 12 hours. The culture medium was then removed and a blank untreated well was set up. Only 2.0 mL of culture medium containing 903 μM uranyl was added to the control group. Mixed culture medium containing 903 μM uranyl and 550 μg / ml of astragalus extract (ASPⅠ, ASPⅡ) or EDTA-CaNa2 was added to the remaining wells. After administration, the cells were cultured in a carbon dioxide incubator (37°C, 5% CO2) for 24 hours. The original culture medium in the 6-well plate was removed and 1 mL of PBS was added to each well to gently rinse the plate.

[0096] Fluorescence microscopy observation method: add 1.0 mL of TMRE staining working solution, incubate at 37°C in a cell culture incubator for 35 minutes, then add 0.5 mL of DAPI staining solution, continue to culture in a carbon dioxide incubator for 10 minutes, then wash twice with 37°C preheated cell culture solution, and observe the fluorescence under a fluorescence microscope.

[0097] When the uranyl nitrate poisoning concentration was 903 μM and the drug administration concentration was 550 μg / mL, the cell mitochondrial membrane potential level was as follows: Fig.13 As shown, the statistical graph of cell mitochondrial membrane potential fluorescence level is as follows Fig.14 As shown. DAPI was used to locate the nucleus, and TMRE staining was used to observe the mitochondrial activity level in the cell. Under normal conditions, there are a large number of negative charges inside the mitochondria. TMRE is a cationic probe that accumulates in the mitochondrial matrix after entering the cell, and can emit bright orange-red fluorescence; but when cells undergo apoptosis, the mitochondrial membrane potential is lost, the mitochondrial permeability transition pore (MPTP) continues to open, TMRE is released into the cytoplasm, and the intensity of orange-red fluorescence in the mitochondria decreases. The orange-red fluorescence in the uranium treatment group was weak, indicating that uranyl caused the mitochondrial membrane potential of IEC-6 cells to be lost and the mitochondrial activity of the cells to be reduced. There was no significant difference in the fluorescence intensity of mitochondrial membrane potential between the ASPⅠ and ASPⅡ treatment groups and the control group. In contrast, the mitochondrial membrane potential of the uranium treatment group increased significantly, indicating that Astragalus extract has a positive therapeutic effect on the loss of cell mitochondrial membrane potential caused by uranium, and can prevent cell mitochondria from being damaged by uranium. In the group treated with uranium and EDTA-CaNa2, no orange-red fluorescence was observed, indicating that the mitochondrial membrane potential was completely lost. Combining bright field and DAPI staining of the nucleus, it was observed that the number of cells decreased, the nucleus shrank, and small bubbles were observed around it. The nucleus shrank, indicating that the combined toxicity of uranium and EDTA-CaNa2 was high and the cells died. Astragalus extract has the effect of inhibiting the loss of mitochondrial membrane potential of IEC-6 cells, and has a certain role in protecting mitochondrial radiation damage caused by uranium, and has no biological toxicity.

[0098] Study on the protective effect of Astragalus extract on oxidative stress of NRK-52E cells induced by uranyl nitrate:

[0099] Analysis method: Rat renal tubular epithelial cells (NRK-52E cells) in logarithmic growth phase were cultured at a rate of approximately 2×10 5The cells were inoculated at a density of 100 / well in a laser confocal culture dish and cultured at 37°C, 5% CO2 for 12 hours. The culture medium was then removed and 2.0 mL of culture medium containing 903 μM uranyl and 550 μg / mL astragalus extract (ASPⅠ, ASPⅡ) or EDTA-CaNa2 was added. Only 2.0 mL of 903 μM uranyl was added to the control group. After administration, the cells were cultured in a carbon dioxide incubator (37°C, 5% CO2) for 24 hours. The culture medium was collected by aspiration and 1 mL of PBS was added to each well to rinse the culture dish. The original culture medium in the culture dish was removed and 1 mL of PBS was added to the culture dish to gently rinse the well plate. 1 mL of serum-free culture medium and 1 μL of DCFH-DA were added and incubated in a carbon dioxide incubator in the dark for 30 minutes. After the incubation, the original culture medium was removed by aspiration and the cells were washed twice with serum-free culture medium. The fluorescence intensity of active oxygen in the cells was observed under a laser confocal microscope.

[0100] The level of reactive oxygen species and fluorescence intensity in NRK-52E cells Figures 15-16 As shown in the figure, the intracellular reactive oxygen level was detected by DCFH-DA probe. The higher the intracellular oxidative stress level, the stronger the intracellular fluorescence intensity. The intracellular fluorescence intensity of the uranium treatment group was higher than that of other groups, the number of cells decreased significantly, and the cells may die. The fluorescence levels of ASPⅠ and ASPⅡ groups were lower than those of the uranyl treatment group, indicating that the level of cell reactive oxygen in ASPⅠ and ASPⅡ groups was lower than that of the uranyl group, indicating that both ASPⅠ and ASPⅡ could effectively prevent uranyl from causing oxidative damage to NRK-52E cells or had a certain therapeutic effect on uranium-induced cell oxidative damage. In the ASPⅠ treatment group, it was observed that the nuclear fluorescence was stronger than the cytoplasm, and the oxidative stress in the nucleus of NRK-52E cells was stronger than that in the cytoplasm. Obvious dot fluorescence was observed in the cytoplasm of the ASPⅡ treatment group. ASPⅡ had a certain effect on reducing the oxidative stress caused by uranium on cells, but the level of mitochondrial ROS in the cytoplasm was still relatively high. The fluorescence intensity of the cells in the EDTA-CaNa2 group was lower, but the cell morphology changed, the cytoplasm expanded and became foggy, the cell membrane boundary was not obvious, the cells were severely damaged and the cell amount decreased. The reason may be that the combined toxicity of uranyl and EDTA-CaNa2 is more toxic to cells, causing cell death and reduced survival of living cells, so the fluorescence intensity of reactive oxygen species detected is weaker than that of other test groups. ASPⅠ has a better anti-oxidative stress effect on NRK-52E cells than ASPⅡ.

[0101] Study on the protective effect of Astragalus extract on mitochondrial membrane potential of NRK-52E cells oxidized by uranyl nitrate:

[0102] Analysis method: NRK-52E cells in logarithmic growth phase were collected and analyzed at a rate of approximately 2×10 6The cells were inoculated at a density of 100 / well in a laser confocal culture dish and cultured for 12 hours at 37°C and 5% CO2 concentration. The culture medium was then removed and a blank untreated well was set. The control group only added 2.0 mL of culture medium containing 903 μM uranyl, and the other groups added culture medium with a concentration of 903 μM uranyl and 550 μg / ml of Astragalus extract (ASPⅠ, ASPⅡ) or EDTA-CaNa2. After administration, the cells were cultured in a carbon dioxide incubator (37°C, 5% CO2) for 24 hours. The original culture medium in the 6-well plate was removed, and 1 mL of PBS was added to each well to gently rinse the plate. 1.0 mL of TMRE staining working solution was added, and the cells were incubated at 37°C in a cell culture incubator for 35 minutes. Then 0.5 mL of DAPI staining solution was added, and the cells were cultured in a carbon dioxide incubator for 10 minutes. The cells were then washed twice with cell culture solution preheated at 37°C, and the fluorescence was observed under a laser confocal microscope.

[0103] After Astragalus extract was treated in NRK-52E cells, TMRE had an effect on the mitochondrial membrane potential level and fluorescence intensity. Fig.17 As shown. DAPI was used to locate the cell nucleus and observe the mitochondrial activity level in the cell; the mitochondria in the normal state emitted bright orange-red fluorescence, but when the mitochondrial membrane potential was lost, the orange-red fluorescence intensity in the mitochondria decreased. The mitochondrial membrane potential level of the cells in the ASPⅠ and ASPⅡ treatment groups was significantly higher than that in the uranium treatment group, indicating that the use of both kept the mitochondria in the cells active and the cells were not seriously damaged. The fluorescence intensity of the ASPⅡ treatment group was significantly higher than that of the control group cells, and ASPⅡ may also have the effect of activating cell mitochondria. The orange-red fluorescence in the uranium treatment group was weak, indicating that uranyl would cause the mitochondrial membrane potential of NRK-52E cells to be lost, resulting in reduced cell activity and possible apoptosis, while ASPⅠ and ASPⅡ significantly improved the mitochondrial membrane potential. In the group with the combined action of uranium and EDTA-CaNa2, weak orange-red fluorescence was observed, indicating that the mitochondrial membrane potential was completely lost. Combined with DAPI staining of the cell nucleus, it was observed that the number of cells decreased and the cytoplasm was enlarged, indicating that the combined toxicity of uranium and EDTA-CaNa2 was high and the cells died.

[0104] Example 2

[0105] The astragalus extract powder obtained in Example 1 was treated as follows: the astragalus extract powder prepared in Example 1 was placed in a low-temperature corona irradiation device for 30 minutes, the treatment atmosphere was air, the temperature was 20°C, the voltage was 8KV, and the distance was 3cm; the irradiated astragalus extract powder and distilled water were mixed at a mass volume ratio of 1g:200mL, stirred and dissolved to obtain solution A; sodium polyphosphate and sodium trimetaphosphate were mixed at a mass ratio of 5:1, the obtained mixed phosphate was mixed with distilled water at a mass volume ratio of 1g:20mL, stirred and dissolved to obtain solution B; solution A and solution B were mixed evenly at a mass ratio of 1:15 between the astragalus extract powder and the mixed phosphate, 0.1mol / L NaOH solution was added to adjust the pH to 8.0, and the reaction was carried out in a constant temperature water bath at 75°C for 3h. After the reaction was completed, it was dialyzed with distilled water for 72h and freeze-dried to obtain a modified astragalus extract powder.

[0106] In this embodiment, the astragalus extract powder is first treated with low-temperature corona irradiation to improve its water solubility and surface activity, which is beneficial to the subsequent reaction. The astragalus extract powder is then modified using sodium polyphosphate and sodium trimetaphosphate. The two have a synergistic effect and can effectively improve the solubility and biological activity of the astragalus extract powder and enhance its uranium excretion-promoting effect.

[0107] Example 3

[0108] The astragalus extract powder obtained in Example 1 was treated as follows: the astragalus extract powder prepared in Example 1 was mixed with distilled water at a mass volume ratio of 1 g: 200 mL, stirred and dissolved to obtain solution A; sodium polyphosphate and sodium trimetaphosphate were mixed at a mass ratio of 5: 1, and the obtained mixed phosphate was mixed with distilled water at a mass volume ratio of 1 g: 20 mL, stirred and dissolved to obtain solution B; solution A and solution B were evenly mixed at a mass ratio of 1:15 between the astragalus extract powder and the mixed phosphate, 0.1 mol / L NaOH solution was added to adjust the pH to 8.0, and the mixture was reacted in a constant temperature water bath at 75°C for 3 h. After the reaction was completed, the mixture was dialyzed with distilled water for 72 h and freeze-dried to obtain a modified astragalus extract powder.

[0109] The modified astragalus extract powders prepared in Examples 2-3 were tested for their excretion-promoting effects on mice exposed to different uranium doses, and the results of the uranium excretion rates in mice are shown in Table 2. It can be seen that the excretion rates of uranium in mice with feces and urine at different exposure doses were calculated, and the modified astragalus extract powders prepared in Examples 2-3 were better than those in Example 1 in promoting the excretion of uranium in the digestive tract of mice, among which the modified astragalus extract powder in Example 2 had the best excretion-promoting effect.

[0110] Table 2

[0111]

[0112]

[0113] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and the implementation modes, and they can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and the illustrations shown and described herein.

Claims

1. A method for preparing an astragalus extract powder, characterized in that: The following steps are involved: Step 1: Take the slices of Astragalus, crush them into particles, soak them in water, continue to add water, heat and heat to perform the first extraction, filter, set aside the filtrate, add water again, heat and heat to perform the second extraction, filter, combine the filtrate, concentrate under reduced pressure, cool to room temperature, then add 95% ethanol, leave at room temperature, and collect the precipitate; Step 2, adding an equal amount of water to the precipitate obtained in step 1, stirring while adding, after the precipitate is dissolved, adding 95% ethanol, stirring evenly, precipitating with alcohol, collecting the precipitate and the supernatant respectively, and drying the precipitate to obtain Astragalus extract I; Step 3, adding 95% ethanol to the supernatant obtained in step 2, stirring evenly, precipitating with alcohol, collecting the precipitate, and drying to obtain Astragalus extract II; Step 4: Mix and grind the Astragalus extract I obtained in step 2 and the Astragalus extract II obtained in step 3 to obtain an Astragalus extract powder.

2. The method for preparing an astragalus extract powder according to claim 1, characterized in that: In the step 1, soaking in water specifically includes: adding water 2 to 4 times the mass of the Astragalus and soaking for 1 to 2 hours.

3. The method for preparing an astragalus extract powder according to claim 1, characterized in that: In the step 1, water is continuously added so that the total mass of the water is 8 to 12 times the mass of the astragalus.

4. The method for preparing an astragalus extract powder according to claim 1, characterized in that: In the step 1, the extraction temperature of the first extraction and the second extraction are both 90-100° C., and the extraction time is both 1-3 hours.

5. The method for preparing an astragalus extract powder according to claim 1, characterized in that: In the step 1, the reduced pressure is used for concentration to a density of 1.11 to 1.

19.

6. The method for preparing an astragalus extract powder according to claim 1, characterized in that: In the step 1, 95% ethanol is added to make the ethanol content 70%; and the mixture is left at room temperature for 20 to 28 hours.

7. The method for preparing an astragalus extract powder according to claim 1, characterized in that: In the step 2, 95% ethanol is added to make the ethanol content 35%; and the alcohol precipitation is carried out for 20 to 28 hours.

8. The method for preparing an astragalus extract powder according to claim 1, characterized in that: In the step 3, 95% ethanol is added to make the ethanol content 70%; and the alcohol precipitation is carried out for 20 to 28 hours.

9. Use of the astragalus extract powder prepared by the preparation method according to any one of claims 1 to 8 in the preparation of radionuclide stimulating and protective drugs.

10. The use of the astragalus extract powder according to claim 9 in the preparation of radionuclide stimulating and protective drugs, characterized in that: The nuclide is uranium.

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