Qiamagu polysaccharide and its extraction method and application

Abstract

The present invention provides chamagu polysaccharide, its extraction method, and applications. The structure of chamagu polysaccharide is as follows: #imgabs0#. Chamagu polysaccharide has significant uric acid-lowering potential, thus opening up new avenues for the development of chamagu extracts in food and health products, as well as new uric acid-lowering drugs.

Description

Technical Field

[0001] The present invention relates to the fields of drug development and functional food technology, and in particular to a chamagu polysaccharide and an extraction method and application thereof. Background Art

[0002] With the accelerated pace of modern life and changes in dietary habits, the incidence of hyperuricemia and gout has increased annually, becoming major metabolic diseases affecting human health. Uric acid is the end product of purine metabolism, and its balance in the body depends primarily on its production and excretion. Hyperuricemia is the biochemical basis of gout, and urate deposition in joints and other tissues can trigger acute attacks of gout.

[0003] Currently, the main treatments for hyperuricemia and gout include medication and lifestyle adjustments. However, long-term use of certain medications may cause side effects, and some patients may develop tolerance or intolerance to the medications. Therefore, the development of new, safe and effective uric acid-lowering active substances is of great clinical significance.

[0004] Chamagu (Brassica rapa L.), a traditional medicinal plant, contains a variety of bioactive components, including polysaccharides, flavonoids, and glucosinolates, in its roots, stems, leaves, and seeds. Due to their unique bioactivity and minimal toxicity, these polysaccharides are considered a promising class of uric acid-lowering substances. However, relatively little research has been conducted on chamagu polysaccharides, and their structure and uric acid-lowering activity remain largely unstudied. Summary of the Invention

[0005] The present invention aims to solve one of the technical problems in the prior art to at least a certain extent. To this end, one object of the present invention is to provide a chamagu polysaccharide and an extraction method and application thereof.

[0006] In the first aspect of the present invention, the present invention provides a chamagu polysaccharide. According to an embodiment of the present invention, the structure of the chamagu polysaccharide is as follows:

[0007] .

[0008] According to the above-mentioned embodiment of the present invention, the activity of Chamagu polysaccharide was explored using a xanthine oxidase model, indicating that the Chamagu polysaccharide of the present application has good uric acid-lowering potential, thereby opening up new ideas for the development of Chamagu extracts in food and health products, and new drugs for lowering uric acid.

[0009] In some embodiments of the present invention, the molecular weight of the chamagu polysaccharide is 57.56 kDa.

[0010] In some embodiments of the present invention, the molar ratio of the monosaccharides in the chamagu polysaccharide is: fucose: arabinose: galactose: glucose: galacturonic acid: glucuronic acid = 0.1: 0.45: 0.27: 98.53: 0.27: 0.30.

[0011] In a second aspect of the present invention, a method for extracting the above-mentioned chamagu polysaccharide is provided. According to an embodiment of the present invention, the method comprises:

[0012] (1) After crushing the chamagu, it is subjected to defatting, ultrasonic alkali extraction, decolorization, protein removal, alcohol precipitation and dialysis in sequence to obtain the crude chamagu polysaccharide;

[0013] (2) The crude chamagu polysaccharide is purified by a DEAE-52 cellulose anion exchange column and a Sephadex G-150 gel chromatography column in sequence to obtain chamagu polysaccharide.

[0014] According to the method for extracting chamagu polysaccharide according to the above embodiment of the present invention, the method has the advantages of simple operation, low cost and high efficiency. The obtained chamagu polysaccharide has high purity and strong activity, and is expected to play an important role in the treatment of hyperuricemia and gout.

[0015] In some embodiments of the present invention, in step (1), the degreasing includes: soaking the chamagu in anhydrous ethanol.

[0016] As an example, fresh chamagu can be sliced, freeze-dried and crushed, then 8 to 12 times the amount of anhydrous ethanol is added, soaked for 0.5 h to 0.8 h, placed in a magnetic stirrer at 45 to 55 ° C and stirred for 2 h to 2.5 h, repeated twice, filtered and dried to obtain chamagu defatted powder.

[0017] In some embodiments of the present invention, in step (1), the ultrasonic alkaline extraction comprises: ultrasonically extracting the defatted chamagu powder obtained after defatting in an alkaline solution to obtain an extract. The inventors have discovered that the chamagu polysaccharide of the structure of the present application can be obtained by using the ultrasonic alkaline extraction method.

[0018] In some embodiments of the present invention, in the ultrasonic alkali extraction, the concentration of the alkali in the alkali solution is 0.08 mol / L to 0.12 mol / L, for example, 0.08 mol / L, 0.09 mol / L, 0.10 mol / L, 0.11 mol / L, 0.12 mol / L, etc.

[0019] In some embodiments of the present invention, the alkali in the alkaline solution includes at least one of NaOH and KOH.

[0020] In some embodiments of the present invention, the mass ratio of the defatted chamagu powder to the alkaline solution is 1:(15-25), thereby increasing the yield of the chamagu polysaccharide of the present application.

[0021] In some embodiments of the present invention, the ultrasonic extraction is performed at a temperature of 55° C. to 65° C. for 2 h to 4 h, thereby increasing the yield of the chamagu polysaccharide of the present application.

[0022] In some embodiments of the present invention, the power of the ultrasonic extraction is 150W to 250W, thereby increasing the yield of the chamagu polysaccharide of the present application.

[0023] In some embodiments of the present invention, in step (1), the decolorization comprises: adding activated carbon to the extract and decolorizing at 35°C to 40°C for 0.8 to 1.5 hours to obtain a supernatant. Furthermore, the amount of activated carbon added is 4% to 6% of the mass of the extract.

[0024] In some embodiments of the present invention, in step (1), the protein removal comprises: adding 0.3 to 1 times the volume of the supernatant to the supernatant for extraction, wherein the sevage reagent is composed of chloroform and n-butanol in a volume ratio of 4:1, centrifuging to remove the protein layer, and then rotary evaporating to remove the organic reagent to obtain a protein-removed solution. Furthermore, the above-mentioned extraction and centrifugal protein removal can be repeated several times to remove as much protein as possible.

[0025] In some embodiments of the present invention, in step (1), the alcohol precipitation comprises: adding 3 to 5 times the volume of anhydrous ethanol to the deproteinized solution to adjust the ethanol concentration in the mixed solution to 75% to 85%, allowing the solution to stand, and centrifuging to obtain a precipitate. Furthermore, after the above-mentioned standing, precipitation is again performed with 80% ethanol for 12 hours, and centrifuging to obtain a precipitate.

[0026] In some embodiments of the present invention, in step (1), the precipitate is dissolved in ultrapure water and dialyzed in a dialysis bag with a molecular weight cut-off of 8000 Da for 60 to 80 hours. Furthermore, the dialysis is performed at room temperature.

[0027] In some embodiments of the present invention, in step (2), the eluents used for purification using the DEAE-52 cellulose anion exchange column are 0 mol / L, 0.1 mol / L, 0.2 mol / L, 0.3 mol / L, and 0.4 mol / L sodium chloride solutions, respectively, and the volumes of the sodium chloride solutions of different concentrations are independently 1.5 to 2 L. Furthermore, the elution rate of the eluent is 4 ml / min to 6 ml / min. Using the above-mentioned DEAE-52 cellulose anion exchange column purification process, the crude chamagu polysaccharide of the present application can be purified.

[0028] In some embodiments of the present invention, before the crude chamagu polysaccharide is purified by the DEAE-52 cellulose anion exchange column, the crude chamagu polysaccharide is dissolved in ultrapure water, centrifuged, and filtered through a 0.45 μm filter membrane. This removes as much excess impurities as possible and obtains a higher purity chamagu polysaccharide.

[0029] As an example, 3 g of chamagu crude polysaccharide was dissolved in an appropriate amount of ultrapure water, centrifuged at 10,000 rpm for 5 min, filtered through a 0.45 µm filter membrane, and purified using a DEAE-52 cellulose anion exchange column (5× 100 cm). The eluents were 0, 0.1, 0.2, 0.3, and 0.4 M sodium chloride solutions at an elution rate of 5 mL / min. Equal amounts were collected (50 mL / tube), and the polysaccharide content was detected by the phenol-sulfuric acid method. The eluents were collected, concentrated, and vacuum-freeze-dried to obtain ultrapure water elution components for further separation and purification.

[0030] In some embodiments of the present invention, in step (2), the eluent used in the Sephadex G-150 gel chromatography column purification is ultrapure water. Furthermore, the elution rate of the eluent is 0.4 ml / min to 0.6 ml / min. Using the above-mentioned Sephadex G-150 gel chromatography column purification process, the chamagu polysaccharide of the present application can be purified.

[0031] In some embodiments of the present invention, before purification on a Sephadex G-150 gel chromatography column, the sample purified on a DEAE-52 cellulose anion exchange column is centrifuged and then filtered through a 0.45 µm filter membrane to remove excess impurities as much as possible and obtain a higher purity of the chamagu crude polysaccharide.

[0032] As an example, the above-mentioned eluted freeze-dried sample with a concentration of 15 mg / mL was centrifuged at 10,000 rpm for 5 minutes, passed through a 0.45 µm filter membrane, and purified using a Sephadex G-150 gel chromatography column (2.6× 50 cm). The eluent was ultrapure water at an elution rate of 0.5 mL / min. Equal amounts were collected (5 mL / tube), and the polysaccharide content was detected by the phenol-sulfuric acid method. The eluate was collected, then concentrated and vacuum-freeze-dried to obtain Chamagu polysaccharide.

[0033] In the third aspect of the present invention, the present invention proposes the use of the above-mentioned Chamagu polysaccharide or the Chamagu polysaccharide extracted by the above-mentioned method in the fields of medicine, food, health care products or cosmetics.

[0034] The present invention has at least the following technical effects:

[0035] (1) The present invention uses a xanthine oxidase model to explore the activity of chamagu polysaccharide, indicating that the chamagu polysaccharide of the present application has good uric acid-lowering potential, thereby opening up new ideas for the development of chamagu extracts in food and health products, and new drugs for lowering uric acid.

[0036] (2) The method for extracting chamagu polysaccharide of the present invention has the advantages of simple operation, low cost and high efficiency. The obtained chamagu polysaccharide has high purity and strong activity, and is expected to play an important role in the treatment of hyperuricemia and gout. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions in the present invention or the prior art, a brief introduction is given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0038] Figure 1 This is the elution curve of the Qiamagu polysaccharide BRPA-1 of Example 1 of the present invention;

[0039] Figure 2 This is a high performance liquid chromatogram of the Qiamagu polysaccharide BRPA-1 of Example 1 of the present invention;

[0040] Figure 3 This is an infrared spectrum of the Qiamagu polysaccharide BRPA-1 of Example 1 of the present invention;

[0041] Figure 4 This is a monosaccharide composition analysis diagram of the chamagu polysaccharide BRPA-1 of Example 1 of the present invention;

[0042] Figure 5 This is the GC-MS total ion current diagram of the Qiamagu polysaccharide BRPA-1 of Example 1 of the present invention;

[0043] Figure 6 This is a graph showing the uric acid-lowering activity of the Chamagu polysaccharide BRPA-1 according to Example 1 of the present invention. DETAILED DESCRIPTION

[0044] Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative work shall fall within the scope of protection of the present invention. The present invention will be described below with reference to specific embodiments. It should be noted that these embodiments are merely illustrative and do not limit the present invention in any way. Example

[0045] (1) Extraction of Qiamagu polysaccharides

[0046] Fresh chamagu was cut into 1 cm thick slices, freeze-dried, and then crushed in a grinder. The slices were then heated with anhydrous ethanol in a magnetic stirrer at 50°C for 2 h. This process was repeated twice. After filtration, the defatted chamagu powder was dried in a 40°C oven. 0.1 mol / L sodium hydroxide was added at a mass ratio of 1:20 for the defatted chamagu powder to sodium hydroxide solution, and the weight was recorded. After soaking for 30 min, ultrasonic extraction was performed at 200 W and 60°C for 3 h. After extraction, the original weight was replenished with 0.1 mol / L sodium hydroxide, and the mixture was centrifuged at 10,000 rpm for 15 min. After centrifugation, the residue was extracted again, and the filtrates from the two extractions were combined. The combined filtrates were then concentrated to 1 / 4 of their original volume using a rotary evaporator. The concentrate was added to 4% activated carbon, decolorized at 40°C for 1 hour, and centrifuged at 10,000 rpm for 15 minutes to obtain the supernatant. Extraction was then performed several times with 1 / 4 volume of sevage reagent (chloroform: n-butanol = 4:1) until no protein precipitated after standing for a period of time. The supernatant was aspirated and rotary evaporated to remove the organic reagent. Next, 4 volumes of anhydrous ethanol were slowly added with thorough stirring, and the mixture was allowed to stand at 4°C overnight. The resulting precipitate was collected and repeatedly washed with 80% ethanol. Finally, the precipitate was dried at room temperature and reconstituted with ultrapure water. After dissolution, it was placed in a dialysis bag with a molecular weight cutoff of 8,000 Da and dialyzed for three days, with the dialysis water changed every four hours. After storage at -80°C for one day, the crude chamagu polysaccharide was freeze-dried.

[0047] (2) Purification of Chamagu polysaccharide

[0048] 100 g of DEAE-52 cellulose was weighed and swollen in sonicated ultrapure water for 2 hours, repeated several times until the upper layer was free of impurities. The filter residue was first soaked in 0.5 mol / L NaOH solution for 2 hours and then washed with ultrapure water until neutral. It was then soaked in 0.5 mol / L HCl solution for another 2 hours and then washed with ultrapure water until neutral. Finally, the filter residue was soaked in 0.5 mol / L NaOH solution for another 2 hours and thoroughly washed with ultrapure water until neutral. For column loading, DEAE-52 cellulose was slowly poured into a 50 × 1000 mm chromatography column using a funnel. The column was then flushed with 5 column volumes of ultrapure water for 12 hours. All eluates were sonicated. Chamagu polysaccharide was prepared into a 15 mg / mL aqueous solution and centrifuged at 10,000 rpm for 5 minutes. The supernatant was filtered through a 0.45 µm syringe filter and loaded. Each sample volume was 50 mL. Gradient elution was performed using 0 M, 0.1 M, 0.2 M, 0.3 M, and 0.4 M NaCl solutions. The eluate was collected using an automated collector at a flow rate of 4–6 mL / min, with equal amounts (50 mL / tube) collected. Polysaccharide content was determined using the phenol-sulfuric acid method. Each sample was loaded several times, and the fraction corresponding to the highest peak in the water elution curve was collected. The fraction was concentrated, dialyzed, freeze-dried, and stored under vacuum to obtain a water-wash fraction.

[0049] Weigh 25 g of Sephadex G-150 dextran gel and swell it in 2 L of ultrapure water for three days. Boil it at 90°C for 0.5 h, and then sonicate it. Slowly pour it into a chromatography column (2.6 × 50 cm). The chamagu polysaccharide purified on the DEAE-52 cellulose anion exchange column was prepared into a 15 mg / mL aqueous solution. The solution was centrifuged at 10,000 rpm for 5 min, and the supernatant was filtered through a 0.45 µm syringe filter and loaded. Each load was 5 mL. The eluate was eluted with ultrapure water and collected in an automated collection system at a flow rate of 0.4–0.6 mL / min. A constant amount of 5 mL was collected per tube. Polysaccharide content was determined using the phenol-sulfuric acid method. Each sample was loaded several times, and the fractions were collected, concentrated, freeze-dried, and stored under vacuum to obtain the chamagu polysaccharide BRPA-1.

[0050] The elution curve of the Qiamagu polysaccharide BRPA-1 of Example 1 is as follows: Figure 1 shown.

[0051] The structure of the chamagu polysaccharide BRPA-1 prepared in Example 1 was characterized:

[0052] (1) Determination of molecular weight

[0053] High-performance liquid chromatography was used using a Waters HPLC system equipped with size exclusion chromatography and a multi-angle laser light scattering detector connected to a Shodex806 column. 0.1 M sodium chloride solution was used as the mobile phase, the column temperature was 35°C, and the flow rate was 0.5 mL / min. 10 mg of polysaccharide was weighed and dissolved in 5 mL of mobile phase, filtered through a 0.45 µm aqueous filter, and placed in an injection bottle for chromatographic analysis. Figure 2 As shown, the measurement result is a single peak with a symmetrical peak shape and a molecular weight of 57.56 kDa.

[0054] (2) Infrared spectroscopy analysis

[0055] 1.00 mg of polysaccharide sample and 100 mg of dried anhydrous potassium bromide powder were accurately weighed in a mortar and quickly ground into a uniform powder. The powder was transferred into a mold to obtain a uniform, transparent, crack-free thin sheet. The thin sheet was analyzed by Fourier transform infrared spectrometer at 4000 cm -1 ~400cm -1 Scan 60 times within the range with a resolution of 4cm -1 , observe the absorption characteristic peaks of the infrared spectrum to analyze the sample (such as Figure 3 The results show that at 3393.56cm -1 and 2927.86cm -1 The strong absorption peaks at 1644.43 cm-1 are caused by the stretching vibrations of OH and CH in polysaccharides; -1 and 1415.66cm -1 The vicinity is attributed to C=O and C=H stretching vibrations; at 1081.62 cm -1 The absorption peak at 853.71 cm-1 can be attributed to the absorption peak caused by CO stretching vibration, indicating the presence of glucopyranose ring in BRPA-1. -1 The absorption peak at α-glycosidic bond is a polysaccharide with α-glycosidic bond and glucopyranose ring.

[0056] (3) Monosaccharide composition analysis

[0057] Accurately weigh 10.00 mg of polysaccharide into a hydrolysis tube. Add 4 mL of 4 mol / L trifluoroacetic acid. Purge the tube with nitrogen for 1 minute to expel air. Tighten the screw cap and hydrolyze at 120°C for 4 hours. After cooling, blow dry the hydrolyzate with nitrogen. Add an appropriate amount of methanol and continue blowing with nitrogen to remove excess trifluoroacetic acid. Add ultrapure water to a volume of 10 mL. Dilute 20-fold, filter through a 0.2 µm filter, and inject. Chromatographic separation conditions: CarboPacTM PA20 3×150 mm column; eluent: 250 mM NaOH and 1 M NaAC; detector: pulsed amperometric detector, gold electrode; flow rate: 0.5 mL / min; injection volume: 10 µL; column temperature: 35°C; mobile phase A: water, B: 250 mM NaOH, C: 1 M NaAC; elution conditions: 0-20 min, 94% A, 6% B, 0% C; 20-20.1 min, 89% A, 6% B, 5% C; 20.1-35 min, 74% A, 6% B, 20% C; 35-35.1 min, 20% A, 80% B, 0% C; 35.1-45 min, 20% A, 80% B, 0% C; 45-45.1 min, 94% A, 6% B, 0% C; 45.1-55 min, 94% A, 6% B, 0% C. Figure 4 As shown, six monosaccharides were identified in BRPA-1, namely fucose, arabinose, galactose, glucose, galacturonic acid, and glucuronic acid, with the ratios of 0.1:0.45:0.27:98.53:0.27:0.30, respectively.

[0058] (4) Methylation analysis

[0059] A 10 mg sample of completely dried polysaccharide was dissolved in 1 mL of DMSO solution and 20 mg of finely powdered NaOH was added. The mixture was stirred in a magnetic stirrer until completely dissolved. 2 mL of iodomethane was slowly added dropwise, and the mixture was sonicated for 30 minutes. After completion, the reaction was allowed to stand for 30 minutes, and then 2 mL of purified water was added to terminate the reaction. The product was then removed and dialyzed for 48 hours. The product was aspirated with a pipette and extracted with dichloromethane. The organic phase was placed in a round-bottom flask and rotary evaporated to dryness. The evaporated product was dried in a vacuum oven at 60°C overnight. The methylation reaction was repeated twice. After treatment, the product was hydrolyzed with 2 M TFA at 120°C for 2 hours, reduced with NaBD4, and acetylated with acetic anhydride to obtain partially methylated alditol acetates. These acetates were analyzed by gas chromatography-mass spectrometry using an HP-5 MS fused silica capillary column (30 m × 0.25 mm, 0.25 µm, Agilent). The column temperature was set at 120°C during injection, then raised to 280°C at a rate of 4°C per minute and maintained at 280°C for 5 minutes. The carrier gas was helium. The GC-MS total ion chromatogram of the obtained methylated sugar alcohol acetyl ester (e.g. Figure 5 GC-MS detected 11 alditol acetates, indicating the presence of 11 bonding modes in BRPA-1, namely Araf-(1, Glcp-(1, 5)-Araf-(1, 2)-Glcp-(1, 3)-Glcp-(1, 4)-Glcp-(1, 6-Glcp-(1, 3, 4)-Glcp-(1, 2, 4)-Glcp-(1, 4, 6)-Glcp-(1 and 3, 4, 6)-Glcp-(1. Based on the relative molar ratios of the various alditol acetates and monosaccharide analysis, it can be inferred that BRPA-1 is mainly composed of 1,4-Glcp.

[0060] (5) Nuclear magnetic resonance spectroscopy analysis

[0061] The polysaccharide was completely dissolved in 500 μL of D2O. 1H NMR, 13C NMR, COSY, HSQC, and HMBC spectra were scanned using a Bruker spectrometer (700 MHz).

[0062] The 1H NMR spectrum of BRPA-1 revealed six hydrogen signal peaks at the sugar terminal groups. The relevant carbon signals in the HSQC and 13C NMR spectra were matched, and the H and C signals of the sugar residues A, B, C, D, and E were determined using 1H NMR, HMBC, and 1H-1H COSY spectra. Combined with the monosaccharide composition and methylation analysis results of BRPA-1, the structure of the chamagu polysaccharide BRPA-1 was determined as follows: It mainly includes (4)-α-D-Glcp-(1→, →4,6)-α-D-Glcp-(1→), α-D-Glcp(1→, →3,4)-β-D-Glcp-(1→, →4)-β-D-Glcp-(1→), and α-L-Araf(1→).

[0063]

[0064] (6) Biological activity

[0065] Xanthine oxidase (XOD) inhibitory activity was measured using a microplate reader using xanthine as a substrate. Blank, enzyme reaction, experimental, and control groups were set up. 50 µL of xanthine as a substrate was added to all groups. The experimental and control groups were treated with different concentrations of polysaccharide solutions (1, 2, 4, 6, 8, and 10 µg / mL). The blank and enzyme reaction groups were replaced with 0.01 M PBS buffer. After preincubation at 37°C for 15 minutes in the dark, 50 µL of 0.1 U / mL XOD was added to the enzyme reaction and experimental groups to initiate the reaction. The blank and control groups were replaced with 0.01 M PBS buffer. After mixing, the samples were reacted at 37°C for 15 minutes. The absorbance was measured at 295 nm. All measurements were repeated three times. The inhibition rate of different concentrations of chamagu polysaccharide against xanthine oxidase was calculated according to the following method.

[0066] Inhibition rate (%) = (1-[A3-A4] / [A1-A2]) × 100%, where A1, A2, A3, and A4 represent the absorbance at 295 nm of the enzyme reaction group, blank group, experimental group, and control group, respectively.

[0067] The inhibitory effect of BRPA-1 on xanthine oxidase is as follows Figure 6 As shown in the results, the addition of gradient concentrations of chamagu polysaccharide BRPA-1 can significantly inhibit the activity of xanthine oxidase, and the inhibitory effect increases with the increase of BRPA-1 concentration.

[0068] In addition, the biological activity of alkali-extracted Chamagu polysaccharide is closely related to its inherent properties, including monosaccharide composition, molecular weight, type of glycosidic bond, main chain structure, etc. The present invention discloses a new structure Chamagu polysaccharide BRPA-1, which not only contains →4)-α-D-Glcp-(1→, →4,6)-α-D-Glcp-(1→, α-D-Glcp-(1→, 3,4)-α-D-Glcp-(1→, →4)-β-D-Glcp-(1→, but also contains α-L-Araf(1→. Although there are relatively few studies on the effect of Chamagu polysaccharide in lowering blood uric acid levels, this study successfully revealed that Chamagu polysaccharide has a good effect in inhibiting uric acid production through in vitro xanthine oxidase model experiments. This discovery not only enriches the understanding of the biological activity of Chamagu polysaccharide, but also provides a new perspective and potential direction for the further development and application of Chamagu in the field of medical health.

[0069] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A chamagu polysaccharide, characterized in that The structure of the Qiamagu polysaccharide is as follows: ； The molar ratio of each monosaccharide in the chamagu polysaccharide is: fucose: arabinose: galactose: glucose: galacturonic acid: glucuronic acid = 0.1: 0.45: 0.27: 98.53: 0.27: 0.

30.

2. The Qiamagu polysaccharide according to claim 1, characterized in that The molecular weight of the chamagu polysaccharide is 57.56 kDa.

3. A method for extracting the chamagu polysaccharide according to claim 1 or 2, characterized in that: include: (1) After crushing the chamagu, it is subjected to defatting, ultrasonic alkali extraction, decolorization, protein removal, alcohol precipitation and dialysis in sequence to obtain chamagu crude polysaccharide; in the ultrasonic alkali extraction, the concentration of the alkali solution used is 0.08mol / L~0.12mol / L; the alcohol precipitation comprises: adding 3~5 times the volume of anhydrous ethanol to the protein removal solution obtained after protein removal, making the ethanol concentration in the mixed solution 75%~85%, and then standing, and obtaining a precipitate after centrifugation; (2) Purify the crude chamagu polysaccharide through a DEAE-52 cellulose anion exchange column, collect the water elution fraction, and then purify the water elution fraction through a Sephadex G-150 gel chromatography column to obtain chamagu polysaccharide.

4. The method according to claim 3, characterized in that In step (1), the degreasing comprises: soaking the chamagu in anhydrous ethanol; The ultrasonic alkali extraction comprises: ultrasonically extracting the defatted chamagu powder obtained after defatting in an alkali solution to obtain an extract; The decolorization comprises: adding activated carbon to the extract and decolorizing at 35° C. to 40° C. for 0.8 to 1.5 hours to obtain a supernatant; The protein removal comprises: adding 0.3 to 1 times the volume of the supernatant to the supernatant for extraction, wherein the sevage reagent is composed of chloroform and n-butanol in a volume ratio of 4:1, centrifuging to remove the protein layer, and then rotary evaporating to remove the organic reagent to obtain a protein removal solution; The precipitate was dissolved in ultrapure water and dialyzed in a dialysis bag with a molecular weight cut-off of 8000 Da for 60 to 80 hours.

5. The method according to claim 4, characterized in that: The alkali in the alkali solution includes at least one of NaOH and KOH; The mass ratio of the Qiamagu defatted powder to the alkaline solution is 1: (15-25); The ultrasonic extraction temperature is 55°C to 65°C, and the time is 2h to 4h; The power of the ultrasonic extraction is 150W~250W.

6. The method according to claim 5, characterized in that In step (2), the eluent used for the Sephadex G-150 gel chromatography column purification is ultrapure water; The elution rate of the eluent is 0.4 ml / min to 0.6 ml / min.

7. The method according to claim 3, characterized in that Before the crude polysaccharide of Qiamagu is purified by the DEAE-52 cellulose anion exchange column, the crude polysaccharide of Qiamagu is dissolved in ultrapure water, centrifuged and filtered through a 0.45 μm filter membrane; Before purification on the Sephadex G-150 gel chromatography column, the sample purified on the DEAE-52 cellulose anion exchange column was centrifuged and then filtered through a 0.45 µm filter membrane.

8. Use of the chamagu polysaccharide described in claim 1 or 2 or the chamagu polysaccharide extracted by the method described in any one of claims 3 to 7 in the medical field, food field or health care product field for non-therapeutic purposes.

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