Brassica rapa polysaccharide as well as extraction method and application thereof

Abstract

The invention provides brassica rapa polysaccharide as well as an extraction method and application thereof. The structure of the brassica rapa polysaccharide is as follows: # imgabs0 #. The Brassica rapa polysaccharide has good potential of reducing uric acid, so that a new thought of the Brassica rapa extract in research and development of foods, health care products and new drugs for reducing uric acid is developed.

Description

Technical Field

[0001] The present invention relates to the technical field of drug development and functional food, and in particular to chamacarp polysaccharide and an extraction method and application thereof. Background Art

[0002] With the acceleration of modern life and changes in eating habits, the incidence of hyperuricemia and gout has increased year by year, becoming an important metabolic disease affecting human health. Uric acid is the final product of purine metabolism, and its balance in the body mainly depends on the production and excretion of uric acid. Hyperuricemia is the biochemical basis of gout, and the deposition of urate in joints and other tissues will trigger an acute attack of gout.

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

[0004] Chamagu (Brassica rapa. L.), as a traditional medicinal plant, contains polysaccharides, flavonoids, glucosinolates and other bioactive ingredients in its roots, stems, leaves and seeds. Polysaccharides are considered to be a class of potential uric acid-lowering active substances due to their unique biological activity and low toxic side effects. However, there are relatively few studies on chamagu polysaccharides, and their structure and uric acid-lowering activity have not been fully elucidated. Summary of the invention

[0005] The present invention aims to solve one of the technical problems in the prior art at least to 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] According to the chamagu polysaccharide of the above 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.

[0008] In some embodiments of the present invention, the molecular weight of the chamagu polysaccharide is 57.56 kDa.

[0009] In some embodiments of the present invention, 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.

[0010] In a second aspect of the present invention, the present invention provides a method for extracting the above-mentioned chamagu polysaccharide. According to an embodiment of the present invention, the method comprises: (1) After crushing the chamagu, the chamagu is subjected to defatting, ultrasonic alkali extraction, decolorization, protein removal, alcohol precipitation and dialysis in sequence to obtain chamagu crude polysaccharide; (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.

[0011] According to the method for extracting chamaguli polysaccharides according to the above embodiment of the present invention, the method has the advantages of simple operation, low cost and high efficiency. The obtained chamaguli polysaccharides have high purity and strong activity, and are expected to play an important role in the treatment of hyperuricemia and gout.

[0012] In some embodiments of the present invention, in step (1), the degreasing includes: soaking the chamagu in anhydrous ethanol.

[0013] As an example, fresh chamaguchi 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 and stirred at 45 to 55 ° C for 2 h to 2.5 h, repeated twice, filtered and dried to obtain chamaguchi defatted powder.

[0014] In some embodiments of the present invention, in step (1), the ultrasonic alkali extraction comprises: ultrasonically extracting the defatted chamagu powder obtained after defatting in an alkali solution to obtain an extract. The inventors have found that the chamagu polysaccharide of the structure of the present application can be obtained by using the ultrasonic alkali extraction method.

[0015] In some embodiments of the present invention, in the ultrasonic alkali extraction, the concentration of the alkali in the alkali solution is 0.08mol / L to 0.12mol / L, for example, 0.08mol / L, 0.09mol / L, 0.10mol / L, 0.11mol / L, 0.12mol / L, etc.

[0016] In some embodiments of the present invention, the alkali in the alkaline solution includes at least one of NaOH and KOH.

[0017] 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.

[0018] In some embodiments of the present invention, the temperature of the ultrasonic extraction is 55°C to 65°C, and the time is 2h to 4h, so as to improve the yield of the chamagu polysaccharide of the present application.

[0019] 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.

[0020] 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.

[0021] 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 extraction and centrifugal protein removal can be repeated several times to remove the protein as much as possible.

[0022] 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, making the ethanol concentration in the mixed solution 75% to 85%, and then standing, centrifuging to obtain a precipitate. Furthermore, after the above standing, 80% ethanol is used again for precipitation for 12 hours, and centrifuging to obtain a precipitate.

[0023] 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 h to 80 h. Furthermore, the dialysis is performed at room temperature.

[0024] In some embodiments of the present invention, in step (2), the eluents used for purification by 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. The above-mentioned DEAE-52 cellulose anion exchange column purification process can be used to purify the chamagu crude polysaccharide of the present application.

[0025] 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 and filtered through a 0.45µm filter membrane after centrifugation, thereby removing excess impurities as much as possible and obtaining a higher purity chamagu polysaccharide.

[0026] 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 eluent was 0, 0.1, 0.2, 0.3, and 0.4 M sodium chloride solution. The elution rate was 5 mL / min, and equal amounts were collected (50 mL / tube). The polysaccharide content was detected by the phenol-sulfuric acid method, and the eluent was collected, then concentrated and vacuum freeze-dried to obtain the ultrapure water elution component for further separation and purification.

[0027] 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. The chamagu polysaccharide of the present application can be purified by using the above-mentioned Sephadex G-150 gel chromatography column purification process.

[0028] In some embodiments of the present invention, before purification by Sephadex G-150 gel chromatography column, the sample purified by DEAE-52 cellulose anion exchange column is centrifuged and filtered through a 0.45µm filter membrane, thereby removing excess impurities as much as possible and obtaining a higher purity of chamagu crude polysaccharide.

[0029] As an example, the above eluted freeze-dried sample with a concentration of 15 mg / mL was centrifuged at 10,000 rpm for 5 min, 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 eluent was collected, then concentrated and vacuum-freeze-dried to obtain Chamaglucoside polysaccharide.

[0030] 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.

[0031] The present invention has at least the following technical effects: (1) The present invention uses a xanthine oxidase model to explore the activity of chamagu polysaccharides, indicating that the chamagu polysaccharides of the present application have 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.

[0032] (2) The method for extracting chamaguli polysaccharides of the present invention has the advantages of simple operation, low cost and high efficiency. The obtained chamaguli polysaccharides have high purity and strong activity, and are expected to play an important role in the treatment of hyperuricemia and gout. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces 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 creative work.

[0034] Figure 1 This is the elution curve of the Chamagu polysaccharide BRPA-1 of Example 1 of the present invention; Figure 2 is a high performance liquid chromatogram of the chamagu polysaccharide BRPA-1 of Example 1 of the present invention; Figure 3 is an infrared spectrum of the chamagu polysaccharide BRPA-1 of Example 1 of the present invention; Figure 4 This is a monosaccharide composition analysis diagram of the chamagu polysaccharide BRPA-1 of Example 1 of the present invention; Figure 5 This is the GC-MS total ion current diagram of the chamagu polysaccharide BRPA-1 of Example 1 of the present invention; Figure 6 This is a graph showing the uric acid lowering activity of the chamacarp polysaccharide BRPA-1 of Example 1 of the present invention. DETAILED DESCRIPTION

[0035] Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. The present invention is 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.

[0036] Example 1

[0037] (1) Extraction of chamagu polysaccharides

[0038] Fresh chamagu was cut into 1 cm thick chamagu slices, freeze-dried and crushed with a pulverizer, heated and stirred with anhydrous ethanol in a magnetic stirrer at 50 ° C for 2 h, and the above operation was repeated twice. After filtration, the defatted chamagu powder was dried in an oven at 40 ° C. 0.1 mol / L NaOH was added at a mass ratio of 1:20 between the defatted chamagu powder and the sodium hydroxide solution, and the weight was recorded. After soaking for 30 min, ultrasonic extraction was performed at 200w and 60 ° C for 3 h. After the extraction, 0.1 mol / L NaOH was added to the original weight, and then centrifuged at 10000 r / min for 15 min. After centrifugation, the filter residue was extracted again, and the filtrates from the two extractions were combined. Next, the combined filtrate was concentrated to 1 / 4 of the original volume using a rotary evaporator. The concentrate was added with 4% activated carbon, decolorized at 40℃ for 1 h, centrifuged at 10000r / min for 15min, and the supernatant was obtained. Then, 1 / 4 volume of sevage reagent (chloroform: n-butanol = 4:1) of the supernatant was added for extraction several times until no protein layer was precipitated after standing for a period of time. The supernatant was aspirated, rotary evaporated, and the organic reagent was removed. Then, 4 times the volume of anhydrous ethanol was slowly added, and it was fully stirred at the same time, and then stood at 4℃ overnight. After overnight, the precipitate was collected and repeatedly washed with 80% ethanol. Finally, the precipitate was dried at room temperature, and the precipitate was re-dissolved with ultrapure water. After dissolution, it was placed in a dialysis bag with a molecular weight cutoff of 8000Da, dialyzed for three days, and the dialysis water was changed every 4h. After being stored at -80℃ for one day, it was freeze-dried to obtain the crude polysaccharide of Chamagu.

[0039] (2) Purification of Chamagu polysaccharide

[0040] Weigh 100g of DEAE-52 cellulose and add ultrapure water that has been ultrasonicated to swell for 2h, several times until there is no impurity in the upper layer. The filter residue was first soaked in 0.5mol / L NaOH solution for 2h, and then washed with ultrapure water until neutral. Then continue to soak in 0.5mol / L HCl solution for 2h, and then wash with ultrapure water until neutral. Finally, soak the filter residue again in 0.5mol / L NaOH solution for 2h, and thoroughly wash with ultrapure water until neutral. When loading the column, use a funnel to slowly pour DEAE-52 cellulose into the chromatography column (50×1000 mm), flush the column with 5 times the column volume of ultrapure water for 12h, and all eluents are ultrasonically treated. The chamagu polysaccharide was prepared into a 15mg / mL aqueous solution, centrifuged at 10000r / min for 5min, and the supernatant was filtered through a 0.45µm needle filter and loaded. The sample volume was 50 mL each time, and 0 M, 0.1 M, 0.2 M, 0.3 M and 0.4 M NaCl solutions were used for gradient elution. The eluate was collected by an automatic collector at a flow rate of 4-6 mL / min, and equal amounts were collected (50 mL / tube). The polysaccharide content was detected by the phenol-sulfuric acid method. Each sample was loaded several times, and the corresponding tube array fraction with the highest peak of the water elution curve was collected, concentrated, dialyzed, and stored after vacuum freeze drying to obtain a water-washed fraction.

[0041] Weigh 25g of Sephadex G-150 dextran gel, add 2L of ultrapure water to swell for three days, boil at 90℃ for 0.5h, and slowly pour into a chromatography column (2.6×50 cm) after ultrasonic treatment. The chamagu polysaccharide purified by the above DEAE-52 cellulose anion exchange column was prepared into a 15mg / mL aqueous solution, centrifuged at 10000r / min for 5min, and the supernatant was filtered through a 0.45µm needle filter and loaded. The loading volume was 5mL each time, eluted with ultrapure water, and the eluate was collected by an automatic collector at a flow rate of 0.4~0.6mL / min, and equal amounts were collected (5mL / tube). The polysaccharide content was detected by the phenol-sulfuric acid method. Each sample was loaded several times, the components were collected, concentrated, and stored after vacuum freeze-drying to obtain the chamagu polysaccharide BRPA-1.

[0042] The elution curve of the Qiamagu polysaccharide BRPA-1 of Example 1 is as follows: Figure 1 shown.

[0043] The structure of the chamagu polysaccharide BRPA-1 prepared in Example 1 was characterized: (1) Determination of molecular weight

[0044] High performance liquid chromatography was used, equipped with a Waters HPLC system connected in series with a size exclusion chromatography and a multi-angle laser light scattering detector and a Shodex806 column, with 0.1M sodium chloride solution as the mobile phase, column temperature of 35°C, and a flow rate of 0.5mL / min. 10mg of polysaccharide was weighed and dissolved in 5mL of mobile phase, filtered through a 0.45µm water 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.

[0045] (2) Infrared spectroscopy analysis

[0046] 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 flake. The flake 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 the polysaccharide; -1 and 1415.66cm -1 The vicinity is attributed to C=O and C=H stretching vibrations; at 1081.62 cm -1 The absorption at 853.71 cm-1 can be attributed to the absorption peak caused by CO stretching vibration, indicating the presence of a glucopyranose ring in BRPA-1. -1 The absorption peak at is the α-glycosidic bond. Therefore, BRPA-1 is a polysaccharide connected by α-glycosidic bonds and having a glucopyranose ring.

[0047] (3) Monosaccharide composition analysis

[0048] Weigh 10.00 mg of polysaccharide accurately into a hydrolysis tube, add 4 mL of 4 mol / L trifluoroacetic acid, fill with nitrogen for 1 minute to expel the air in the tube, tighten the screw cap, hydrolyze at 120°C for 4 hours, blow dry the hydrolyzate with nitrogen after cooling, add an appropriate amount of methanol and blow nitrogen again to remove excess trifluoroacetic acid, add ultrapure water to make up to 10 mL, dilute 20 times, filter with 0.2µm filter membrane, and inject. Chromatographic separation conditions: CarboPacTMPA20 3×150mm column; eluent: 250mM NaOH and 1M NaAC; detector: pulsed amperometric detector, gold electrode; flow rate: 0.5mL / min; injection volume: 10µL; column temperature: 35℃; mobile phase A: water, B: 250mM NaOH, C: 1M 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; 35-35.1min, 20% A, 80% B, 0% C; 35.1-45min, 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, and their ratios were 0.1:0.45:0.27:98.53:0.27:0.30, respectively.

[0049] (4) Methylation analysis

[0050] 10 mg of completely dried polysaccharide sample was added to 1 mL of DMSO solution with 20 mg of fine powdered NaOH, and N2 was filled. Each mixture was stirred in a magnetic stirrer to completely dissolve. 2 mL of iodomethane was slowly dripped in, and ultrasonic reaction was carried out for 30 min. After the reaction was completed, it was allowed to stand for 30 min, and 2 mL of purified water was added to terminate the reaction. The reactant was taken out and dialyzed for 48 h. The product was sucked out with a dropper, extracted with dichloromethane, and the organic phase was placed in a round-bottom flask and rotary evaporated to dryness. The evaporated product was placed in a vacuum drying oven and vacuum dried 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, then reduced with NaBD4, and then acetylated with acetic anhydride to obtain partially methylated alditol acetate. 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 methylated sugar alcohol acetyl ester obtained (such as Figure 5 GC-MS detected 11 alditol acetates, that is, there are 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 ratio of each alditol acetate and monosaccharide analysis, it can be inferred that BRPA-1 is mainly composed of 1,4-Glcp.

[0051] (5) Nuclear magnetic resonance spectroscopy analysis

[0052] The polysaccharide was completely dissolved in 500 µL D2O. 1H NMR, 13C NMR, COSY, HSQC, and HMBC spectra were scanned using a Bruker spectrometer (700 MHz).

[0053] The 1H NMR spectrum of BRPA-1 showed 6 hydrogen signal peaks of sugar terminal groups. The relevant carbon signals in the HSQC spectrum and 13C NMR spectrum were matched, and the H and C signal correlation signals of each sugar residue fragment A, B, C, D, and E were determined by 1H NMR, HMBC, and 1H-1H COSY spectrum. Combined with the results of monosaccharide composition and methylation determination of BRPA-1, the structure of BRPA-1 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→).

[0054] (6) Biological activity

[0055] Xanthine was used as a substrate, and the XOD inhibitory activity of the samples was detected by an ELISA instrument. A blank group, an enzyme reaction group, an experimental group, and a control group were set up. 50 µL of xanthine was added to all groups as a reaction substrate. Different concentrations of polysaccharide solutions (1, 2, 4, 6, 8, and 10 µg / mL) were added to the experimental group and the control group. The blank group and the enzyme reaction group replaced the chaga polysaccharide aqueous solution with 0.01M PBS buffer. After pre-incubation at 37°C in the dark for 15 min, 50 µL of 0.1 U / mL XOD was added to the enzyme reaction group and the experimental group to initiate the reaction. The blank group and the control group replaced XOD with 0.01M PBS buffer. After mixing evenly, the mixture was reacted at 37°C for 15 min, and the absorbance was measured at 295 nm. All measurements were repeated three times. The inhibition rate of different concentrations of chaga polysaccharide on xanthine oxidase was calculated according to the following method.

[0056] Inhibition rate (%) = (1-[A3-A4] / [A1-A2]) × 100%, where A1, A2, A3, and A4 represent the absorbance of the enzyme reaction group, blank group, experimental group, and control group at 295 nm, respectively.

[0057] The inhibitory effect of BRPA-1 on xanthine oxidase is as follows Figure 6 As shown, 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.

[0058] In addition, the biological activity of alkaline-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 on lowering blood uric acid levels, this study successfully revealed that Chamagu polysaccharide has a good effect in inhibiting uric acid production through an in vitro xanthine oxidase model experiment. 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.

[0059] 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 embodiments of the present invention.

Claims

1. A chamagu polysaccharide, characterized in that The structure of the chamagu polysaccharide is as follows: 。 2. The chamagu polysaccharide according to claim 1, characterized in that The molecular weight of the chamagu polysaccharide is 57.56 kDa.

3. The chamagu polysaccharide according to claim 1 or 2, characterized in that 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.

4. A method for extracting chamagu polysaccharide according to any one of claims 1 to 3, characterized in that: include: (1) After crushing the chamagu, the chamagu is subjected to defatting, ultrasonic alkali extraction, decolorization, protein removal, alcohol precipitation and dialysis in sequence to obtain chamagu crude polysaccharide; (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.

5. The method according to claim 4, characterized in that: In step (1), the degreasing comprises: soaking the chamagu in anhydrous ethanol; And / or, the ultrasonic alkali extraction comprises: ultrasonically extracting the defatted chamagu powder obtained after defatting in an alkali solution to obtain an extract; And / or, the decolorization comprises: adding activated carbon to the leaching solution for decolorization at 35° C. to 40° C. for 0.8 to 1.5 hours to obtain a supernatant; And / or, 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; And / or, the alcohol precipitation comprises: adding 3 to 5 times the volume of anhydrous ethanol to the deproteinizing solution, making the ethanol concentration in the mixed solution 75% to 85%, then standing, and centrifuging to obtain a precipitate; And / or, dissolving the precipitate in ultrapure water and dialyzing it in a dialysis bag with a molecular weight cut-off of 8000 Da for 60 h to 80 h.

6. The method according to claim 5, characterized in that: In the ultrasonic alkali extraction, the concentration of alkali in the alkali solution is 0.08mol / L~0.12mol / L; And / or, the alkali in the alkali solution includes at least one of NaOH and KOH; And / or, the mass ratio of the chamagu defatted powder to the alkaline solution is 1:(15-25); And / or, the temperature of the ultrasonic extraction is 55°C to 65°C, and the time is 2h to 4h; And / or, the power of the ultrasonic extraction is 150W~250W.

7. The method according to claim 4, characterized in that: In step (2), the eluents used for purification by 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; And / or, the elution rate of the eluent is 4 ml / min~6 ml / min.

8. The method according to claim 4, characterized in that: In step (2), the eluent used in the Sephadex G-150 gel chromatography column purification is ultrapure water; And / or, the elution rate of the eluent is 0.4 ml / min~0.6 ml / min.

9. The method according to claim 4, characterized in that: Before the crude chamagu polysaccharide is purified by the DEAE-52 cellulose anion exchange column, the crude chamagu polysaccharide is dissolved in ultrapure water, and then centrifuged and filtered through a 0.45 μm filter membrane; And / or, before purification by Sephadex G-150 gel chromatography column, the sample purified by DEAE-52 cellulose anion exchange column is centrifuged and then filtered through a 0.45 µm filter membrane.

10. Use of the chamagu polysaccharide described in any one of claims 1 to 3 or the chamagu polysaccharide extracted by the method described in any one of claims 4 to 9 in the fields of medicine, food, health care products or cosmetics.

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