Use of phoebe extract in preparation of drugs for preventing and / or treating chronic colitis

Abstract

The application relates to application of spondias mombin extract in preparation of medicines for preventing and / or treating chronic colitis, and belongs to the technical field of biological medicines. The spondias mombin extract with a polysaccharide content of more than 60% can relieve the shortening of the colon, reduce intestinal inflammatory cell infiltration, surface epithelial damage and loss of goblet cells, and reduce the DAI score and the histological double-blind score of an animal model, so that the spondias mombin extract can play a role in treating chronic colitis.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of biological medicine, and particularly relates to application of Livistona chinensis seed extract in preparation of drugs for preventing and / or treating chronic colitis. BACKGROUND

[0002] Chronic colitis is a chronic, recurrent, multiple, inflammatory edema of the intestinal tract caused by various pathogenic reasons, ulceration, hemorrhagic lesions, and clinical manifestations of chronic diarrhea, repeated abdominal pain, and complications of other inflammations such as arthritis, iridocyclitis, liver dysfunction, etc. The etiology of chronic colitis is complex, and common causes are non-specific enteritis, such as irritable bowel syndrome, inflammatory bowel disease, intestinal flora imbalance, and small intestinal malabsorption. It is generally believed that chronic colitis is related to infection, immune inheritance, environment, food allergy, prevention dysfunction, and mental factors.

[0003] Livistona chinensis seed is the seed of Livistona chinensis (Jacq.) R. Br. in the family Arecaceae, with sweet and bitter tastes, and neutral property, which enters the lung, liver, kidney and stomach meridians, and has the effects of activating blood circulation to resolve stasis, softening and resolving masses, and is used for treating chronic hepatitis. Modern medical research has found that Livistona chinensis seed has the effects of antioxidation, liver protection and anti-nasopharyngeal carcinoma, but there is no related report on the prevention and treatment of chronic colitis by Livistona chinensis seed extract mainly containing polysaccharides. SUMMARY

[0004] The present application aims at overcoming the deficiencies of the prior art and providing application of Livistona chinensis seed extract in preparation of drugs for preventing and / or treating chronic colitis.

[0005] To achieve the above object, the technical scheme adopted by the present application is as follows:

[0006] In the first aspect, the present application provides application of Livistona chinensis seed extract in preparation of drugs for preventing and / or treating chronic colitis, wherein the Livistona chinensis seed extract contains polysaccharides.

[0007] The present application first discovers that Livistona chinensis seed extract can effectively treat chronic colitis at the animal experiment level, and it is found that the Livistona chinensis seed extract can significantly reduce the colon shortening, inflammatory cell infiltration, surface epithelial damage and loss of goblet cells caused by chronic colitis, and reduce the DAI score and histological double-blind score of the animal model by treating the chronic colitis animal model with the Livistona chinensis seed extract.

[0008] As a preferred embodiment of the application, the mass percentage of the polysaccharides in the Livistona chinensis seed extract is greater than 60%, and the relative molecular mass of the polysaccharides is 8000-14000 kDa.

[0009] As a preferred embodiment of the application, the dosage form of the medicine for preventing and / or treating chronic colitis is at least one of a capsule, a tablet, an oral preparation, a microcapsule preparation, an injection, a suppository, a spray, an ointment, a gel, a solution, a powder, a lotion, a tincture, an oil, a cream, and an aerosol.

[0010] As a preferred embodiment of the application, the medicine for preventing and / or treating chronic colitis is used for oral administration.

[0011] As a preferred embodiment of the application, the dosage of the medicine for preventing and / or treating chronic colitis for oral administration is 50-100 mg per 1 kg of body weight of the organism. It is found in the experiment that 50-100 mg of the extract of Sterculia lychnophora Hance can significantly reduce the DAI score of the animal model of chronic colitis, and the oral administration dosage of 50-100 mg of the extract of Sterculia lychnophora Hance per 1 kg of body weight of the organism can effectively relieve the symptoms of chronic colitis.

[0012] As a preferred embodiment of the application, the extract of Sterculia lychnophora Hance can reduce intestinal inflammatory cell infiltration, relieve intestinal surface epithelial damage, and loss of goblet cells.

[0013] In a second aspect, the application provides a preparation method of the extract of Sterculia lychnophora Hance, comprising the following steps:

[0014] (1) adding the powder of Sterculia lychnophora Hance into ethanol for defatting, and obtaining the defatted Sterculia lychnophora Hance after the ethanol is volatilized;

[0015] (2) mixing the defatted Sterculia lychnophora Hance obtained in step (1) with water for leaching, filtering, and obtaining the extract of Sterculia lychnophora Hance;

[0016] (3) concentrating the extract of Sterculia lychnophora Hance obtained in step (2), adding ethanol for precipitation, filtering, washing the obtained filter residue, and drying to obtain the crude extract of Sterculia lychnophora Hance;

[0017] (4) decolorizing the crude extract of Sterculia lychnophora Hance obtained in step (3) to obtain the decolorized crude extract of Sterculia lychnophora Hance;

[0018] (5) removing the protein in the decolorized crude extract of Sterculia lychnophora Hance obtained in step (4), then dialyzing, and drying the dialyzed solution to obtain the extract of Sterculia lychnophora Hance.

[0019] The extract of Sterculia lychnophora Hance with a polysaccharide content of more than 60% is successfully extracted and purified by defatting, leaching, alcohol precipitation, decolorization, protein removal, and dialysis, and can be applied in preventing and treating chronic colitis.

[0020] As a preferred embodiment of the preparation method of the present application, in step (1), the defatting method is: mixing the Phoenix tree seed powder with ethanol, and transferring into a reflux device, and refluxing twice in a water bath at 80°C, each time for 2h;

[0021] In step (3), the washing is washing twice with anhydrous ethanol, diethyl ether and acetone;

[0022] In step (4), the decolorizing method is: adding polyamide to the Phoenix tree seed crude extract aqueous solution, and stirring at 50°C for 30min to decolorize; the mass ratio of the Phoenix tree seed crude extract in the Phoenix tree seed crude extract aqueous solution to the polyamide is Phoenix tree seed crude extract: polyamide = 1:4;

[0023] In step (5), the dialysis method is: transferring the protein-removed Phoenix tree seed crude extract into a dialysis bag, dialyzing for 48h under running water at room temperature, and then dialyzing for 24h with distilled water; the specification of the dialysis bag is 8000-14000kDa.

[0024] As a preferred embodiment of the preparation method of the present application, in step (1), the Phoenix tree seed powder is passed through a 60-mesh sieve, and dried at 40°C for 3-4h to obtain;

[0025] In step (2), the mixing method of the defatted Phoenix tree seed and water is: mixing at 30°C for 20min under ultrasonic;

[0026] In step (2), the extraction method is: water bath reflux extraction at 90°C for 2h;

[0027] In step (3), the concentration method is: concentration under reduced pressure at 50°C to a volume of the concentrated Phoenix tree seed extract that is one-fifth of the volume before concentration.

[0028] As a preferred embodiment of the application of the present application, in step (1), the ratio of the Phoenix tree seed powder and ethanol is Phoenix tree seed powder: ethanol = 1g: 10ml, and the ethanol is anhydrous ethanol;

[0029] In step (2), the ratio of the defatted Phoenix tree seed and water is defatted Phoenix tree seed: water = 1g: 20ml;

[0030] In step (3), the addition of ethanol is adding ethanol to the mixture of the Phoenix tree seed extract and ethanol, and the alcohol content is 80%, and the ethanol is anhydrous ethanol.

[0031] As a preferred embodiment of the preparation method of the present application, in step (5), the method for removing the protein in the decolorized crude extract of Phoenix roebelii is: dissolving the decolorized crude extract of Phoenix roebelii into a crude extract solution of Phoenix roebelii, adding a chloroform-n-butanol mixture, standing for stratification after oscillation for 30 min, taking the supernatant after centrifugation, adding the chloroform-n-butanol mixture again and oscillating, and repeating the operation for 8-12 times to remove the protein in the crude extract of Phoenix roebelii.

[0032] The chloroform-n-butanol mixture can destroy the protein structure in the crude extract of Phoenix roebelii, so that the protein loses solubility and can be removed by filtration. The multiple standing for stratification and oscillation can make the protein in the crude extract of Phoenix roebelii react completely with the chloroform-n-butanol mixture, thereby improving the removal rate of the protein. The chloroform-n-butanol mixture has poor solubility for polysaccharides and will not affect the structure of the polysaccharides and cause the precipitation of the polysaccharides, so the chloroform-n-butanol mixture is used to remove the protein in the crude extract of Phoenix roebelii.

[0033] As a preferred embodiment of the preparation method of the present application, the volume ratio of chloroform to n-butanol in the chloroform-n-butanol mixture is chloroform:n-butanol = 4:1, and the volume ratio of the crude extract solution of Phoenix roebelii to the chloroform-n-butanol mixture is crude extract solution of Phoenix roebelii:chloroform-n-butanol mixture = 5:1.

[0034] In a third aspect, the present application provides a medicine for treating chronic colitis, which comprises the extract of Phoenix roebelii.

[0035] As a preferred embodiment of the medicine of the present application, the medicine further comprises a pharmaceutically acceptable carrier.

[0036] Compared with the prior art, the present application has the following beneficial effects:

[0037] The present application first proves at the animal level that the extract of Phoenix roebelii with a polysaccharide content of more than 60% can treat chronic colitis by relieving the shortening of the colon, reducing the intestinal inflammatory cell infiltration, surface epithelial damage and loss of goblet cells, and lowering the DAI score and the histological double-blind score of the animal model. BRIEF DESCRIPTION OF DRAWINGS

[0038] Figure 1 The weight analysis results of the mice in different treatment groups in Example 3 after the 45th day of administration are shown in the figure, where "**" indicates that there is a significant difference between the model group and the control group, P<0.01;

[0039] Figure 2The disease activity index (DAI) analysis results of the mice in different treatment groups in Experimental Example 3 are shown in the figure. "#" indicates a significant difference compared with the control group, P<0.05; "*" indicates a significant difference compared with the model group, P<0.05; "**" indicates a significant difference compared with the model group, P<0.01;

[0040] Figure 3 The colon length comparison chart of the mice in different treatment groups in Experimental Example 3 after 45 days of administration is shown in the figure;

[0041] Figure 4 The colon length statistical results of the mice in different treatment groups in Experimental Example 3 after 45 days of administration are shown in the figure. "####" indicates a significant difference compared with the control group, P<0.0001; "*" indicates a significant difference compared with the model group;

[0042] Figure 5 The colon HE staining results of the mice in different treatment groups in Experimental Example 3 after 45 days of administration are shown in the figure;

[0043] Figure 6 The histopathology score of the mice in different treatment groups in Experimental Example 3 after 45 days of administration is shown in the figure. "####" indicates a significant difference compared with the control group, P<0.0001; "****" indicates a significant difference compared with the model group, P<0.0001;

[0044] Figure 7 The liver toxicity index determination results of the mice in different treatment groups in Experimental Example 3 after 45 days of administration are shown in the figure. DETAILED DESCRIPTION

[0045] In order to better illustrate the purpose, technical scheme and advantages of the present application, the present application will be further described below in conjunction with specific examples.

[0046] The reagents and consumables used in the following experimental examples are commercially available unless otherwise specified.

[0047] Experimental Example 1: Extraction and identification of Phoenix tree fruit extract

[0048] I. Extraction of Phoenix tree fruit extract

[0049] S1, dry the Phoenix tree fruit and crush it with a crusher, then dry it at 40°C for 3-4h after passing through a 60 mesh sieve to obtain Phoenix tree fruit powder;

[0050] S2, the obtained Phoenix tree seed powder in step S1 is added into anhydrous ethanol, and transferred into a reflux device, and refluxed in a water bath at 80℃ for two times, each for 2h, to obtain defatted Phoenix tree seed; the ratio of Phoenix tree seed powder to anhydrous ethanol is Phoenix tree seed powder: anhydrous ethanol = 1g: 10ml;

[0051] S3, the defatted Phoenix tree seed obtained in step S2 is mixed with water at a ratio of defatted Phoenix tree seed: water = 1g: 20ml under ultrasonic at 30℃ for 20min, and transferred into a reflux device, and refluxed in a water bath at 90℃ for 2h, and filtered to obtain Phoenix tree seed extract;

[0052] S4, the Phoenix tree seed extract obtained in step S4 is concentrated by evaporation at 50℃ under reduced pressure to a volume of one fifth of the volume before concentration, anhydrous ethanol is added to the mixture of Phoenix tree seed extract and ethanol to make the alcohol content in the mixture 80%, and precipitated at 4℃ overnight, and filtered, and the obtained filter residue is washed with anhydrous ethanol, diethyl ether and acetone for two times, and dried to obtain Phoenix tree seed crude extract;

[0053] S5, the Phoenix tree seed crude extract obtained in step S4 is prepared into a Phoenix tree seed crude extract aqueous solution, and polyamide is added, and stirred at 50℃ for 30min to decolorize, to obtain decolorized Phoenix tree seed crude extract; the mass ratio of Phoenix tree seed crude extract to polyamide in the Phoenix tree seed crude extract aqueous solution is Phoenix tree seed crude extract: polyamide = 1:4;

[0054] S6, the decolorized Phoenix tree seed crude extract obtained in step S5 is dissolved into a Phoenix tree seed crude extract solution, and chloroform-n-butanol mixed solution (chloroform: n-butanol = 4:1, v / v) is added, and oscillated for 30min, and then separated by standing, and centrifuged, and the supernatant is taken and added with chloroform-n-butanol mixed solution and oscillated again, and the operation is repeated for 8-12 times to remove the protein in the Phoenix tree seed crude extract, and transferred into a dialysis bag, and dialyzed at room temperature under flowing water for 48h, and then dialyzed with distilled water for 24h to obtain Phoenix tree seed extract; the volume ratio of Phoenix tree seed crude extract solution to chloroform-n-butanol mixed solution is Phoenix tree seed crude extract solution: chloroform-n-butanol mixed solution = 5:1; the specification of the dialysis bag is 8000-14000kDa.

[0055] II. Identification of Phoenix tree seed extract.

[0056] The polysaccharide content in the extracted Phoenix tree seed extract is determined by sulfuric acid-phenol method, and the determination result is that the polysaccharide content in the Phoenix tree seed extract obtained in the experimental example is 62.17%, which proves that the Phoenix tree seed extract with polysaccharide content of more than 60% is successfully extracted.

[0057] Experimental example 2 Influence of Phoenix tree seed extract on chronic colitis mice

[0058] In order to verify whether the sago fruit extract has the effect of treating chronic colitis, the effect of the sago fruit extract on treating chronic colitis is evaluated through an animal experiment, and the specific scheme is as follows:

[0059] I. Establishment of a mouse model of chronic colitis

[0060] SPF level C57BL / 6J male mice (8 weeks old, 20-22g BW) were used as experimental objects, and after weighing, they were divided into a modeling group and an untreated group.

[0061] On day 0, the mice in the modeling group were given 1-3% dextran sodium sulfate salt (DSS) for drinking, and the mice in the untreated group were given normal water for drinking;

[0062] On the 2nd day of the experiment, the mice in the modeling group were replaced with 1.5% DSS drinking water;

[0063] On the 4th day of the experiment, the mice in the modeling group were replaced with 1.5% DSS drinking water;

[0064] On the 7th day of the experiment, the mice in the modeling group were replaced with DSS-free drinking water;

[0065] On days 17-21, the operations on days 0-4 were repeated;

[0066] On days 31-35, the operations on days 0-4 were repeated, and the DSS concentration was increased to 3%;

[0067] On day 38, the mice in the modeling group were replaced with DSS-free drinking water.

[0068] The mice had a significant decrease in body weight, and their stools were in a liquid state and had severe occult blood, indicating that the mouse model of chronic colitis was successfully established.

[0069] II. Effect of sago fruit extract on body weight and DAI score of mice

[0070] The following treatment groups were set up in this experiment: a control group, a model group, a low-dose sago fruit extract group, and a high-dose sago fruit extract group. The mice in the control group were given DSS-free drinking water, and the mice in the other treatment groups were given DSS-containing drinking water according to the method of establishing the animal model of chronic colitis. The mice in the low-dose sago fruit extract group were given sago fruit extract at a dose of 50mg / kg, and the mice in the high-dose sago fruit extract group were given sago fruit extract at a dose of 100mg / kg.

[0071] The model group, the low-dose P. subopposita extract group and the high-dose P. subopposita extract group were administered intragastrically from day 0, with a drug solution volume of 0.1 ml / g, for 45 days. The first phase was from day 7 to day 17, the second phase was from day 24 to day 31, and the third phase was from day 38 to day 45. The disease activity index (DAI) of the mice in the three phases was evaluated, and the DAI scoring standard is shown in Table 1. The occult blood in the stool was determined by the test paper method. The results of the body weight of the mice after administration on day 45 are shown in Figure 1 , and the DAI score results are shown in Figure 2 .

[0072] Table 1 DAI Scoring Standard

[0073]

[0074]

[0075] As shown in Figure 1 , compared with the control group, the body weight of the mice in the model group, the low-dose P. subopposita extract group and the high-dose P. subopposita extract group was lower, among which the evaluation body weight of the high-dose P. subopposita extract group was the highest, followed by the low-dose P. subopposita extract group, and then the model group, indicating that P. subopposita extract can alleviate the body weight loss caused by chronic colitis.

[0076] As shown in Figure 2 , in the DAI score of the three phases, the mice in the control group were completely normal, while the score of the model group was significantly increased. The scores of the low-dose and high-dose P. subopposita extract groups decreased to different degrees. In the third phase, the DAI scores of the low-dose and high-dose P. subopposita extract groups decreased by 35.56% and 44.45% respectively compared with the model group, which indicated that P. subopposita extract can significantly reduce the DAI score of chronic colitis mice, i.e. P. subopposita extract has the effect of relieving and treating chronic colitis.

[0077] III. Effect of P. subopposita extract on colon length, spleen weight and histopathology of mice

[0078] The mice in each treatment group in Experiment III were randomly selected and sacrificed and dissected on day 45 of the experiment. The colon tissue, spleen tissue and liver tissue were removed. The colon length of the mice was measured, the colon tissue was subjected to HE and PAS staining and histological double-blind scoring (the scoring standard is shown in Table 2); the ALT, AST and AST / ALT indexes of the liver of the mice were determined, and the above results are shown in Figures 3-7 .

[0079] Table 2 Scoring Standard for Apparent Pathological Changes of Animal Colon Tissue (Histological Double-Blind Scoring)

[0080] Score Epithelial integrity Inflammatory cell infiltration 0 Normal morphology No infiltration 1 Absence of goblet cells Pericryptal infiltration 2 Most goblet cells absent Infiltration of mucosa layer 3 Absence of crypts Massive infiltration of mucosa layer 4 Most crypts absent Submucosal infiltration

[0081] As shown in Figure 3 , the colon of the control group mice was observed to have an intact inner wall, regular folds, and clear blood vessel texture, with no visible erosion, ulcer, or granuloma, and only slight hyperemia in a few cases. The colon of the model group was observed to be shortened, with a thin intestinal wall, significant mucosal hyperemia and edema, scattered erosion or ulcer with bleeding, and a large area of ulceration. The colon length of the model group was significantly shorter than that of the control group. The colon of the mice in the low- and high-dose groups of the Phoenix Tree Fruit Extract was also observed to have varying degrees of pathological damage, but the colon length and thinning of the intestinal wall were improved to varying degrees.

[0082] As shown in Figure 4 , compared with the model group, the average colon length of the mice in the high-dose group of the Phoenix Tree Fruit Extract was significantly increased, and the average colon length of the mice in the low-dose group of the Phoenix Tree Fruit Extract was not significantly changed, indicating that the high dose of the Phoenix Tree Fruit Extract can effectively improve the shortening of the colon length caused by chronic colitis.

[0083] As shown in Figure 5 , the colon mucosal epithelial cells of the control group mice were arranged in an orderly manner, and no atrophy, deformation, necrosis, or inflammatory cell infiltration was observed. The goblet cells were abundant, and the lamina propria had capillaries and a small amount of inflammatory cells. The pathological sections of the DSS model group had typical acute stage pathological manifestations, including multiple colon ulcers, reduced or absent goblet cells, crypt destruction and abscess formation, complete loss of epithelium or only a small amount of residual epithelium, and inflammatory cell infiltration of the mucosa and submucosa. The colon surface mucosa of the mice in the low- and high-dose groups of the Phoenix Tree Fruit Extract was basically restored, the ulcers healed well, the goblet cells increased, the crypt inflammation significantly decreased, and the neutrophils in the mucosa and submucosa significantly decreased, but the interstitium still had a small amount of lymphocyte infiltration.

[0084] As shown in Figure 6 , the histological double-blind score of the control group was very low, the score of the model group was significantly higher than that of the control group, and the score of the high-dose group of the Phoenix Tree Fruit Extract was significantly lower than that of the model group, but the score of the low-dose group of the Phoenix Tree Fruit Extract had no significant difference from that of the model group.

[0085] The above data indicates that the Phoenix Tree Fruit Extract can relieve chronic colitis by healing colon ulcers and reducing inflammation.

[0086] As shown in Figure 7 , the different treatment groups had no significant effect on the ALT and AST indicators of the mice, indicating that the Phoenix Tree Fruit Extract of the present application does not affect the liver function of animals.

[0087] In summary, the experiment found that the sago palm fruit extract can significantly alleviate the shortening of the colon caused by chronic colitis, indicating that the treatment effect of the sago palm fruit extract is mainly aimed at the intestinal tract; through further research, it was found that the sago palm fruit extract with a polysaccharide content of more than 60% has the effect of repairing the inflamed intestinal tract, specifically manifested as significantly alleviating the shortening of the colon, reducing inflammatory cell infiltration, surface epithelial damage and loss of goblet cells, and it can be seen that the sago palm fruit extract has the effect of preventing and / or treating chronic colitis.

[0088] Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the present application and are not a limitation on the protection scope of the present application. Although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can be modified or replaced by equivalents without departing from the essence and scope of the technical solutions of the present application.

Claims

1. The use of fan palm seed extract in the preparation of drugs for the prevention and / or treatment of chronic colitis; wherein the fan palm seed extract contains fan palm seed polysaccharides; The mass percentage of fan palm seed polysaccharide in the fan palm seed extract is greater than 60%; the relative molecular mass of the fan palm seed polysaccharide is 8000-14000 kDa.

2. The application as described in claim 1, characterized in that, The dosage form of the drug for the prevention and / or treatment of chronic colitis is at least one of the following: capsules, tablets, microcapsules, suppositories, sprays, ointments, gels, solutions, powders, lotions, tinctures, oils, creams, and aerosols.

3. The application as described in claim 1, characterized in that, The medication for the prevention and / or treatment of chronic colitis is for oral administration.

4. The application as described in claim 3, characterized in that, The oral dosage of the drug for the prevention and / or treatment of chronic colitis is 50-100 mg per kg of body weight.

5. A method for preparing a fan palm seed extract, characterized in that, Includes the following steps: (1) Add the palm seed powder to ethanol to defatt the seeds, and after the ethanol evaporates, the defatted palm seeds are obtained. (2) The defatted palm seeds obtained in step (1) are mixed with water and then extracted and filtered to obtain palm seed extract; (3) Concentrate the extract of fan palm seeds obtained in step (2), add ethanol to precipitate, filter, wash the obtained filter residue, dry, and obtain crude extract of fan palm seeds; (4) Decolorize the crude extract of fan palm seeds obtained in step (3) to obtain the decolorized crude extract of fan palm seeds; (5) Remove the protein from the decolorized crude extract of fan palm seeds obtained in step (4), then dialyze it, and dry the dialyzed solution to obtain fan palm seed extract; In step (4), the decolorization method is as follows: polyamide is added to the aqueous solution of crude extract of fan palm seeds, and the mixture is stirred at 50°C for 30 min to decolorize; the mass ratio of crude extract of fan palm seeds to polyamide in the aqueous solution of crude extract of fan palm seeds is crude extract of fan palm seeds: polyamide = 1:4; In step (5), the dialysis method is as follows: the crude extract of palm seeds after protein removal is transferred into a dialysis bag and dialyzed at room temperature and running water for 48 hours, followed by dialysis with distilled water for 24 hours; the dialysis bag has a specification of 8000-14000 kDa.

6. The preparation method according to claim 5, characterized in that, In step (1), the degreasing method is as follows: mix the palm seed powder with ethanol, transfer it into a reflux device, and reflux it twice in a water bath at 80°C, each time for 2 hours; In step (3), the washing is performed twice using anhydrous ethanol, ether, and acetone.

7. The preparation method according to claim 5, characterized in that, In step (1), the ratio of the fan palm seed powder to ethanol is fan palm seed powder: ethanol = 1g: 10ml, and the ethanol is anhydrous ethanol; In step (2), the ratio of defatted palm seeds to water is defatted palm seeds: water = 1g: 20ml; In step (3), the addition of ethanol means adding ethanol until the alcohol content in the mixture of palm seed extract and ethanol is 80%, and the ethanol is anhydrous ethanol.

8. The preparation method according to claim 5, characterized in that, In step (5), the method for removing protein from the decolorized crude extract of fan palm seeds is as follows: dissolve the decolorized crude extract of fan palm seeds into a solution, add chloroform-n-butanol mixture, shake for 30 minutes, allow to stand for layering, centrifuge, take the supernatant, add chloroform-n-butanol solution again and shake, repeat 8-12 times to remove protein from the crude extract of fan palm seeds.

9. The preparation method according to claim 8, characterized in that, The volume ratio of chloroform to n-butanol in the chloroform-n-butanol mixture is chloroform:n-butanol = 4:1, and the volume ratio of the crude extract solution of fan palm seeds to the chloroform-n-butanol mixture is 5:1.

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