Use of a chaga extract in the preparation of a medicament for preventing and treating alzheimer's disease

Abstract

The application provides application of Qiamagu extract in preparation of medicines for preventing and treating Alzheimer's disease, and belongs to the technical field of biological medicines. The Qiamagu extract has good anti-Alzheimer's disease activity, and has a good application prospect in the medicines for preventing and treating Alzheimer's disease.

Description

Technical Field

[0001] This invention belongs to the field of biomedical technology, specifically relating to the application of Chamaegu extract in the preparation of drugs for the prevention and treatment of Alzheimer's disease. Background Technology

[0002] Alzheimer's Disease (AD) is a neurodegenerative disease characterized by memory and cognitive impairment, commonly known as senile dementia. Unlike typical aging, AD patients experience rapid memory decline, sometimes even completely losing their logical thinking ability, and in later stages, becoming unable to care for themselves. AD is a complex disease with an unclear pathogenesis; the most typical pathological features of the brain are Aβ amyloid protein deposition and neurofibrillary tangles formed by Tau protein hyperphosphorylation.

[0003] Currently, the main drugs used in clinical treatment of Alzheimer's disease (AD) are chemical drugs, which can only slow down the disease progression and have problems such as toxic side effects and drug resistance. Traditional Chinese medicine and ethnic minority medicines, with their multi-component, multi-target, and multi-pathway characteristics, have certain advantages in the treatment of complex diseases like AD. Therefore, research on anti-AD drugs based on traditional Chinese medicine and ethnic minority medicines has become a current hot topic.

[0004] Turnip (Brassicarapa L.), a biennial herbaceous plant belonging to the Brassicaceae family, is distributed throughout China and is a popular vegetable. Its fleshy root is the edible part and is also recorded in traditional Chinese medicine and ethnic minority pharmacopoeias as a medicinal component, possessing high nutritional and medicinal value. Modern research indicates that the fleshy root of turnip contains flavonoids, phenolic acids, saponins, and other compounds, exhibiting various pharmacological effects such as antioxidant, anti-hypoxia, anti-tumor, anti-inflammatory, hypoglycemic, and immunomodulatory properties. Currently, there are no reports on the anti-AD effects of turnip extract. Summary of the Invention

[0005] The purpose of this invention is to provide an application of Chamaegu extract in the preparation of drugs for the prevention and treatment of Alzheimer's disease. The Chamaegu extract described in this invention exhibits good anti-Alzheimer's activity and shows promising application prospects in drugs for the prevention and treatment of Alzheimer's disease.

[0006] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0007] This invention provides the application of Chamaegu extract in the preparation of drugs for the prevention and treatment of Alzheimer's disease;

[0008] The preparation method of the Chamaegu extract includes the following steps:

[0009] Chamaegu was mixed with an ethanol-water solution for extraction to obtain an extract;

[0010] The extract was first concentrated to obtain extract A;

[0011] The extract A is mixed with water to obtain extract B;

[0012] Extract B is extracted with petroleum ether, and the petroleum ether extract residue is collected.

[0013] The petroleum ether extract residue was extracted with ethyl acetate, and the ethyl acetate extract was collected.

[0014] The ethyl acetate extract was further concentrated to obtain the Chamaegu extract.

[0015] Preferably, the volume fraction of the ethanol aqueous solution is 60-90%.

[0016] Preferably, the extraction is performed 2 to 5 times; the material-to-liquid ratio for each extraction is 1g:5 to 50mL.

[0017] Preferably, the extraction includes sequential ultrasonic-assisted extraction and immersion extraction; the ultrasonic-assisted extraction has a power of 60-900W, a temperature of 30-80℃, and a time of 10-60min; the immersion extraction has a temperature of 50-80℃ and a time of 1-4h.

[0018] Preferably, the volume ratio of extract A to water is 1:0.5-10; the volume ratio of extract B to petroleum ether is 1:0.5-10; and the volume ratio of petroleum ether extract residue to ethyl acetate is 1:0.5-10.

[0019] Preferably, the boiling point of the petroleum ether is 60–90°C.

[0020] Preferably, both the first concentration and the second concentration are vacuum concentrations.

[0021] Preferably, the total flavonoid content of the Chamaegu extract is not less than 40 mg rutin equivalents / g Chamaegu extract.

[0022] Preferably, the total phenolic content of the Chamaegu extract is not less than 20 mg gallic acid equivalent / g Chamaegu extract.

[0023] Preferably, the dosage form of the drug for preventing and treating Alzheimer's disease includes at least one of tablets, pills, granules, suspensions, oral liquids, and sprays.

[0024] This invention provides an application of Chamaegu extract in the preparation of drugs for the prevention and treatment of Alzheimer's disease. The Chamaegu extract described in this invention exhibits good anti-Alzheimer's activity and shows promising application prospects in the preparation of Alzheimer's disease drugs. Experimental studies show that in an in vitro PC12 cell model, the Chamaegu extract prepared in this invention can reduce intracellular reactive oxygen species (ROS) levels by improving cellular antioxidant capacity, thereby reducing cell apoptosis. In an in vivo mouse model, the prepared Chamaegu extract can maintain the integrity of nerve cells and reduce Aβ deposition and p-Tau protein production in the hippocampus by reducing the levels of acetylcholinesterase (AChE), β-secretase 1 (BACE1), malondialdehyde (MDA), and inflammatory factors in the brain tissue of Alzheimer's mice, while increasing the levels of antioxidant enzymes such as glutathione peroxidase, superoxide dismutase, and catalase. Furthermore, the anti-AD efficacy of the Chamaegu extract is comparable to that of the positive control drug donepezil hydrochloride, making it an ideal raw material for anti-AD drugs.

[0025] The preparation method of Chamaegu extract according to the present invention includes the following steps: Chamaegu is mixed with an ethanol-water solution for extraction to obtain an extract; the extract is first concentrated to obtain extract A; extract A is mixed with water to obtain extract B; extract B is extracted with petroleum ether, and the petroleum ether extract residue is collected; the petroleum ether extract residue is extracted with ethyl acetate, and the ethyl acetate extract is collected; the ethyl acetate extract is second concentrated to obtain the Chamaegu extract. The present invention, through ethanol-water solution extraction, petroleum ether extraction, and ethyl acetate extraction, can effectively promote the dissolution of flavonoids and phenolic active ingredients, preparing a Chamaegu extract rich in flavonoids and phenolic active ingredients, and the operation is simple. Example results show that the Chamaegu extract prepared by the method provided by the present invention has a total flavonoid content of not less than 40 mg rutin equivalent / g Chamaegu extract and a total phenol content of not less than 20 mg gallic acid equivalent / g Chamaegu extract, exhibiting significant anti-AD activity. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 Figure 1 shows the effect of Chamaegu extract on the survival rate of PC12 cells damaged by H2O2.

[0028] Figure 2Figure 1 shows the effect of Chamaegu extract on ROS in PC12 cells damaged by H2O2 as measured by flow cytometry.

[0029] Figure 3 Figure 1 shows the effect of Chamaegu extract on the intracellular ROS fluorescence intensity of PC12 cells damaged by H2O2.

[0030] Figure 4 Figure showing the effect of Chamaegu extract on H2O2-damaged PC12 cells;

[0031] Figure 5 The graph shows the changes in body weight of mice after different concentrations of Chaga mushroom extract.

[0032] Figure 6 Figure showing the effect of different concentrations of Chaga mushroom extract on the latency period of mice in the plateau hiding phase;

[0033] Figure 7 The graph shows the effects of different concentrations of Chaga extract on the movement trajectory, number of times the original plateau was crossed, and percentage of time spent in the original plateau quadrant of mice without a plateau phase.

[0034] Figure 8 The graph shows the effect of the same concentration of Chamaegu extract on the activities of AChE and BACE1 in the mouse brain.

[0035] Figure 9 The figure shows the effects of different concentrations of Chaga mushroom extract on superoxide dismutase activity, glutathione peroxidase activity, peroxidase activity and MDA level in mouse brain.

[0036] Figure 10 Figure showing the effects of different concentrations of Chaga mushroom extract on the inflammatory factors TNF-α and IL-6 in the mouse brain;

[0037] Figure 11 Image showing HE staining results of mouse brain tissue sections from each group;

[0038] Figure 12 Image showing the Aβ immunohistochemical staining results of brain tissue sections from each group of mice;

[0039] Figure 13 Immunohistochemical staining results of p-Tau protein in brain tissue sections of mice in each group. Detailed Implementation

[0040] This invention provides the application of Chamaegu extract in the preparation of drugs for the prevention and treatment of Alzheimer's disease;

[0041] The preparation method of the Chamaegu extract includes the following steps:

[0042] Chamaegu was mixed with an ethanol-water solution for extraction to obtain an extract;

[0043] The extract was first concentrated to obtain extract A;

[0044] The extract A is mixed with water to obtain extract B;

[0045] Extract B is extracted with petroleum ether, and the petroleum ether extract residue is collected.

[0046] The petroleum ether extract residue was extracted with ethyl acetate, and the ethyl acetate extract was collected.

[0047] The ethyl acetate extract was further concentrated to obtain the Chamaegu extract.

[0048] In this invention, unless otherwise specified, all raw materials used are commercially available products well known to those skilled in the art or prepared using methods well known to those skilled in the art.

[0049] This invention involves extracting *Chamaegu* (a type of wild herb) by mixing it with an ethanol-water solution. Before extraction, *Chamaegu* is preferably pulverized and dried to obtain *Chamaegu* powder. The particle size of the *Chamaegu* powder is preferably not less than 40 mesh. In an embodiment of this invention, the specific steps include: washing fresh *Chamaegu* with clean water, air-drying it, cutting it into 3-5 mm thin slices, air-drying it, pulverizing the slices with a pulverizer, and passing them through a 40-mesh sieve to obtain *Chamaegu* powder for later use. After obtaining the *Chamaegu* powder, this invention involves extracting it by mixing it with an ethanol-water solution. In this invention, the volume fraction of the ethanol-water solution is preferably 60-90%, more preferably 80%. In this invention, the number of extractions is preferably 2-5 times, more preferably 3 times; the material-to-liquid ratio for each extraction is preferably 1g:5-50mL, more preferably 1g:10-25mL. The extraction of this invention preferably includes sequential ultrasonic-assisted extraction and maceration. The preferred power for ultrasonic-assisted extraction in this invention is 60-900W, more preferably 300-500W; the preferred temperature is 30-80℃, more preferably 50-60℃; and the preferred time is 10-60min, more preferably 20-30min. The preferred extraction temperature is 50-80℃, more preferably 50-60℃; and the preferred time is 1-4h, more preferably 2-3h. After each extraction, this invention preferably performs solid-liquid separation to obtain a supernatant and a filter residue, and uses the filter residue for the next extraction; the supernatants obtained from each extraction are combined to obtain the extract. The preferred method of solid-liquid separation in this invention is filtration.

[0050] After obtaining the extract, the present invention performs a first concentration to obtain extract A. In the present invention, the first concentration is preferably vacuum concentration; the temperature of the vacuum concentration is preferably 30–80°C, more preferably 50–60°C. The present invention preferably concentrates the extract under reduced pressure until no alcohol odor remains, obtaining extract A. In the present invention, the instrument for performing the first concentration is preferably a vacuum rotary evaporator.

[0051] After obtaining extract A, the present invention mixes extract A with water to obtain extract B. In the present invention, the volume ratio of extract A to water is preferably 1:0.5 to 10, more preferably 1:1 to 5.

[0052] After obtaining extract B, the present invention extracts extract B with petroleum ether and collects the petroleum ether raffinate. In the present invention, the boiling point of the petroleum ether is preferably 60–90°C, more preferably 70–80°C. In the present invention, the volume ratio of extract B to petroleum ether is preferably 1:0.5–10, more preferably 1:1–5. The present invention preferably extracts until the petroleum ether extract is colorless, then discards the petroleum ether extract to obtain the petroleum ether raffinate.

[0053] After obtaining the petroleum ether raffinate, the present invention extracts the petroleum ether raffinate with ethyl acetate and collects the ethyl acetate extract. In the present invention, the volume ratio of the petroleum ether raffinate to ethyl acetate is preferably 1:0.5–10, more preferably 1:1–5. The present invention preferably extracts until the ethyl acetate extract is colorless, then discards the ethyl acetate raffinate to obtain the ethyl acetate extract.

[0054] After obtaining the ethyl acetate extract, the present invention further concentrates the ethyl acetate extract to obtain the Chamaegu extract. In the present invention, the second concentration is preferably vacuum concentration, and the temperature of the vacuum concentration is preferably 40–65°C, more preferably 50–60°C. After the second concentration, the present invention preferably dries the obtained concentrated material. In the present invention, the drying is preferably vacuum freeze-drying (lyophilization).

[0055] In this invention, the total flavonoid content of the Chamaegu extract is preferably not less than 40 mg rutin equivalent / g Chamaegu extract, and the total phenol content is preferably not less than 20 mg gallic acid equivalent / g Chamaegu extract.

[0056] In this invention, the dosage form of the drug for preventing and treating Alzheimer's disease includes at least one of tablets, pills, granules, suspensions, oral liquids, and sprays.

[0057] The technical solutions of this invention will be clearly and completely described below with reference to the embodiments thereof. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0058] Example 1

[0059] (1) Wash fresh Chamaegu with clean water, dry it, cut it into 3-5mm thin slices, air dry it, crush the slices with a pulverizer and pass them through a 40-mesh sieve to obtain Chamaegu powder for later use.

[0060] Accurately weigh 1 kg of Chamaegu powder, add 80% ethanol aqueous solution (material-liquid ratio of 1:10 g / mL), first extract with ultrasonic assistance for 20 min (temperature of 50℃, power of 300W), turn off the ultrasonic device, and then extract in a 60℃ water bath for 2 h to obtain the extract.

[0061] The extract was filtered through gauze to obtain a supernatant and a filter residue. The filter residue was then extracted twice more under the above conditions. The supernatants obtained after the three extractions were combined and concentrated at 50°C using a vacuum rotary evaporator until no alcohol odor was detected, to obtain extract A.

[0062] (2) Add an equal volume of distilled water to extract A, mix well, and a free-flowing extract B is formed.

[0063] (3) Extract B with an equal volume of petroleum ether (bp, 60-90℃) until the petroleum ether extract is colorless. Discard the petroleum ether extract to obtain the petroleum ether extract residue.

[0064] (4) Extract the petroleum ether extract with an equal volume of ethyl acetate until the ethyl acetate extract is colorless. Discard the ethyl acetate extract and collect the ethyl acetate extract.

[0065] (5) The ethyl acetate extract was concentrated under reduced pressure at 50°C, and the concentrated material was freeze-dried to obtain Chamaegu extract.

[0066] The total flavonoid content in *Chamaegu* extract was determined by the aluminum trichloride colorimetric method, and was 55 mg rutin equivalent / g *Chamaegu* extract. The total phenol content in *Chamaegu* extract was determined by the Folin-Ciocalteu method, and was 25 mg gallic acid equivalent / g *Chamaegu* extract.

[0067] Test Example 1

[0068] The in vitro anti-AD activity of the Chamaegu extract prepared in Example 1 was evaluated:

[0069] Rat adrenal pheochromocytoma cells (PC12 cells) were treated with different concentrations of Chaga mushroom extract (25 μg / mL, 50 μg / mL, 100 μg / mL and 200 μg / mL). After 24 h, the supernatant was removed, and 100 μL of 200 μmol / L H2O2 was added to each well for 4 h. The PC12 cells were then analyzed as follows:

[0070] (1) The morphology of the treated PC12 cells was observed under a microscope, and the results are as follows: Figure 1 As shown in (A) in the diagram.

[0071] Experimental results showed that cells in the H2O2-damaged model group became rounder and their numbers decreased, while the extract of Chamaegu could reduce the degree of cell damage.

[0072] (2) The viability of PC12 cells after treatment was detected by the 3-(4,5-dimethylthiazol-2)-2,5-diphenyltetrazolium bromide method (MTT method), and the results are as follows: Figure 1 As shown in (B) (significant differences in the figure are marked as follows: compared with the blank group, **** is p<0.0001; compared with the H2O2 group, ## is p<0.01, ### is p<0.001, and #### is p<0.0001).

[0073] The experimental results showed that the low and medium dose groups of Chaga extract (25 μg / mL, 50 μg / mL and 100 μg / mL) could significantly improve the survival rate of PC12 cells, and the low dose group (25 μg / mL) had the best effect.

[0074] (3) The detection results of oxidative damage indicators such as MDA, lactate dehydrogenase, glutathione peroxidase, superoxide dismutase, and intracellular reactive oxygen species (ROS) in the treated PC12 cells are as follows: Figures 2-3 As shown.

[0075] Figure 2 The figure shows the effect of Chamaegu extract on ROS in PC12 cells damaged by H2O2, as measured by flow cytometry.

[0076] Figure 3 The figure shows the effect of Chamaegu extract on the intracellular ROS fluorescence intensity of PC12 cells damaged by H2O2.

[0077] Figure 4 The figure shows the effect of Chaga mushroom extract on H2O2-damaged PC12 cells. Figure 4(A) shows the effect of Chaga mushroom extract on malondialdehyde content in PC12 cells damaged by H2O2; (B) shows the effect of Chaga mushroom extract on lactate dehydrogenase activity in PC12 cells damaged by H2O2; (C) shows the effect of Chaga mushroom extract on superoxide dismutase level in PC12 cells damaged by H2O2; and (D) shows the effect of Chaga mushroom extract on glutathione peroxidase in PC12 cells damaged by H2O2.

[0078] Experimental results showed that Chamaegu extract could increase the levels of glutathione peroxidase and superoxide dismutase in a concentration-dependent manner, and decrease the levels of malondialdehyde and lactate dehydrogenase, thereby reducing intracellular ROS and effectively reducing cell apoptosis.

[0079] Test Example 2

[0080] Evaluation of the in vivo anti-AD activity of Chamaegu extract:

[0081] To evaluate the anti-AD effect of Chaga mushroom extract in vivo, an Alzheimer's disease model was established by intraperitoneal injection of D-galactose (120 mg / kg) and NaNO2 (90 mg / kg) 0.2 mL for 60 days, and the weight changes of mice were recorded during the experiment. Thirty days after modeling, mice were randomly divided into a model group, a positive control group, a low-dose group (25 μg / mL), a medium-dose group (50 μg / mL), and a high-dose group (100 μg / mL). Each group of mice was administered the corresponding test drug by gavage (0.2 mL), while the blank control group and the model group were administered physiological saline by gavage (0.2 mL). Behavioral tests were conducted half an hour after the last administration. The day after the behavioral experiments, mice were euthanized by cervical dislocation, and the brain was cut along the midline. One half of the brain tissue was homogenized with cold physiological saline to form a 10% brain tissue homogenate, and the other half was fixed in 4% paraformaldehyde fixative for section preparation.

[0082] (1) Effects of different concentrations of Chamaegu extract on mice.

[0083] Figure 5 The graph shows the changes in body weight of mice after different concentrations of Chaga mushroom extract.

[0084] Figure 6 The figure shows the effect of different concentrations of Chaga mushroom extract on the latency period of mice in the plateau hidden phase.

[0085] Figure 7 The graph shows the effects of different concentrations of Chaga mushroom extract on the movement trajectory, number of times the original plateau was crossed, and percentage of time spent in the original plateau quadrant of mice without a plateau phase. Figure 7(A) shows the effect of different concentrations of Chaga extract on the movement trajectory of mice without a plateau phase; (B) shows the effect of different concentrations of Chaga extract on the number of times mice without a plateau phase cross the original plateau; and (C) shows the effect of different concentrations of Chaga extract on the percentage of time mice without a plateau phase spend in the original plateau quadrant.

[0086] The results showed that administration of Chamaegu extract had no significant effect on the change in body weight in mice. Figure 5 Compared with Alzheimer's disease model mice, the latency of the plateau hiding period was reduced in the medium-dose group of mice. Figure 6 ), and memory and cognitive abilities without plateaus significantly improved ( Figure 7 ).

[0087] (2) Detection results of relevant physicochemical indicators in the mouse brain.

[0088] Figure 8 The figure shows the effect of the same concentration of Chaga mushroom extract on the activities of AChE and BACE1 in the mouse brain. Figure 8 (A) shows the effect of different concentrations of Chaga extract on AChE activity in the mouse brain, and (B) shows the effect of different concentrations of Chaga extract on BACE1 activity in the mouse brain.

[0089] Figure 9 The figure shows the effects of different concentrations of Chaga mushroom extract on superoxide dismutase activity, glutathione peroxidase activity, peroxidase activity, and MDA levels in the mouse brain. Figure 9 (A) shows the effect of different concentrations of Chaga mushroom extract on the activity of superoxide dismutase in the mouse brain; (B) shows the effect of different concentrations of Chaga mushroom extract on the activity of glutathione peroxidase in the mouse brain; (C) shows the effect of different concentrations of Chaga mushroom extract on the activity of peroxidase in the mouse brain; and (D) shows the effect of different concentrations of Chaga mushroom extract on the level of MDA in the mouse brain.

[0090] Figure 10 The figure shows the effects of different concentrations of Chaga mushroom extract on the inflammatory factors TNF-α and IL-6 in the mouse brain. Figure 10 (A) shows the effect of different concentrations of Chaga extract on the inflammatory factor TNF-α in the mouse brain, and (B) shows the effect of different concentrations of Chaga extract on the inflammatory factor IL-6 in the mouse brain.

[0091] The results showed that, compared with the Alzheimer's disease model group of mice, Chaga mushroom extract could reduce the levels of AChE and BACE1 in the brain tissue of mice. Figure 8 ), and increase the activity of antioxidant enzymes such as glutathione peroxidase, superoxide dismutase, and catalase. Figure 8(A), (B), and (C) in the text reduce the content of lipid peroxidation product MDA. Figure 9 (D) and inflammation level ( Figure 10 These results indicate that Chaga mushroom extract at 20 mg / kg can maximally protect the memory capacity of Alzheimer's mice and enhance their cognitive function.

[0092] (3) Staining results of mouse brain tissue sections

[0093] Figure 11 Image showing the results of hematoxylin-eosin (HE) staining of brain tissue sections from each group of mice.

[0094] HE staining results showed that the number of cells in the hippocampus of Alzheimer's mice was reduced, the cell morphology was shrunken, and there was vacuolation in the cortex. Treatment with a medium dose of Chaga extract could significantly improve this phenomenon, and the hippocampus and cortex of the mice were close to those of the normal group of mice.

[0095] Figure 12 Image showing the Aβ immunohistochemical staining results of brain tissue sections from each group of mice; Figure 13 Immunohistochemical staining results of p-Tau protein in brain tissue sections of mice in each group.

[0096] Immunohistochemical staining results showed that Alzheimer's mice had significant deposits of Aβ protein and phosphorylated Tau protein in the hippocampus and cortex, with prominent brown spots. Moderate-dose treatment improved the deposition of Aβ protein and phosphorylated Tau protein in the hippocampus and cerebral cortex, reducing the number of brown spots. Figure 12 and Figure 13 ).

[0097] This invention evaluated the anti-AD activity of Chaga mushroom extract using different methods, including detailed verification through in vitro and in vivo experiments, and elucidated its mechanism of action, finding that Chaga mushroom extract has good anti-AD activity.

[0098] Although the above embodiments have provided a detailed description of the present invention, they are only some embodiments of the present invention, and not all embodiments. People can obtain other embodiments based on these embodiments without creative effort, and these embodiments all fall within the protection scope of the present invention.

Claims

1. The application of a Chamaegu extract in the preparation of drugs for the prevention and treatment of Alzheimer's disease; The preparation method of the Chamaegu extract consists of the following steps: Chamaegu was mixed with an ethanol-water solution for extraction to obtain an extract; The extract was first concentrated to obtain extract A; The extract A is mixed with water to obtain extract B; Extract B is extracted with petroleum ether, and the petroleum ether extract residue is collected. The petroleum ether extract residue was extracted with ethyl acetate, and the ethyl acetate extract was collected. The ethyl acetate extract was further concentrated to obtain the Chamaegu extract. The volume fraction of the ethanol aqueous solution is 60-90%; The extraction is performed 2 to 5 times; the material-to-liquid ratio for each extraction is 1g:5 to 50mL. The extraction process includes sequential ultrasonic-assisted extraction and immersion extraction; the ultrasonic-assisted extraction has a power of 60–900W, a temperature of 30–80℃, and a time of 10–60 min; the immersion extraction has a temperature of 50–80℃ and a time of 1–4 h. The volume ratio of extract A to water is 1:0.5-10; the volume ratio of extract B to petroleum ether is 1:0.5-10; the volume ratio of petroleum ether extract residue to ethyl acetate is 1:0.5-10. The boiling point of the petroleum ether is 60–90°C; The total flavonoid content of the Chamaegu extract is not less than 40 mg rutin equivalents / g Chamaegu extract; The total phenolic content of the Chamaegu extract shall not be less than 20 mg gallic acid equivalent / g Chamaegu extract.

2. The application according to claim 1, characterized in that, The first and second concentrations are vacuum concentrations.

3. The application according to claim 1, characterized in that, The dosage forms of the drugs for preventing and treating Alzheimer's disease include at least one of tablets, pills, granules, suspensions, oral liquids, and sprays.

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