Scallop skirt chitosan glycosaminoglycan, and separation and purification method and application thereof
By combining ion exchange chromatography and stepwise acid hydrolysis with alcohol precipitation and ultrafiltration, glycosaminoglycans from scallop skirts were separated and purified, solving the problem of unclear structure and obtaining high-purity glycosaminoglycans for application in the pharmaceutical field, exhibiting pro-inflammatory activity and immunomodulatory effects.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- INST OF OCEANOLOGY - CHINESE ACAD OF SCI
- Filing Date
- 2026-03-17
- Publication Date
- 2026-06-09
Smart Images
Figure CN122167614A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of marine bioengineering technology, and specifically relates to a scallop skirt glycosaminoglycan, its separation and purification method, and its application. Background Technology
[0002] The human immune system is a vital defense barrier for maintaining health, undertaking key functions such as recognizing and eliminating exogenous pathogens, monitoring and eliminating abnormal or tumor cells, and maintaining homeostasis within the body. It also participates extensively in various physiological processes. Developing and screening safe and effective immunomodulators to improve the body's immune status has become an important direction in current research on immunity and functional substances.
[0003] Glycosaminoglycans (GAGs), also known as acidic mucopolysaccharides, are a class of linear polyanionic animal heteropolysaccharides composed of repeating units of hexuronic acid and hexosamine. Based on their disaccharide composition and glycosidic bonds, they can be classified into heparin, heparan sulfate, hyaluronic acid, chondroitin sulfate, dermatan sulfate, and keratin sulfate. Current research indicates that GAGs are widely involved in various key life processes in the body, possessing diverse biological functions such as anticoagulation, antitumor, antiviral, and antioxidant effects. These diverse structures and unique properties make them valuable for applications in physiological regulation, functional food development, and biomedicine. However, scallop skirts, as a low-value byproduct of marine organisms with abundant resources, are often directly discarded, causing resource waste and environmental pollution; this situation urgently needs improvement.
[0004] Previous studies on scallop-derived glycosaminoglycans have mainly focused on crude polysaccharides, with no reports on isolation techniques for scallop skirt glycosaminoglycans with clearly defined chemical structures. The unclear structural characteristics of scallop-derived glycosaminoglycans, such as sulfation sites, substitution positions, and molecular weight distribution, lead to unclear structure-activity relationships, hindering their development and application. Summary of the Invention
[0005] The purpose of this invention is to provide a glycosaminoglycan from scallop skirts, its separation and purification method, and its application, to solve the problems existing in the prior art. The separation and purification method and application provided by this invention selectively enriches acidic polysaccharides through separation techniques such as ion exchange chromatography to obtain purified glycosaminoglycan components; further, by combining methods such as stepwise acid hydrolysis, its main chain composition and structural characteristics are clarified, thus facilitating subsequent fine structural analysis of the glycosaminoglycan. This also has significant implications for the study of the immunostimulatory activity of glycosaminoglycans with specific structures.
[0006] To achieve the above objectives, the present invention provides the following solution: This invention provides a method for separating and purifying glycosaminoglycans from scallop skirts, comprising the following steps: After mixing and complexing the enzymatic hydrolysate of scallop skirt with a solution of hexadecylpyridine chloride, the crude polysaccharide of scallop skirt was obtained by alcohol precipitation. The crude polysaccharide from scallop skirt was separated by anion exchange column chromatography and ultrafiltration to obtain purified scallop skirt polysaccharide. The purified scallop skirt polysaccharide was subjected to stepwise acid hydrolysis to obtain the scallop skirt glycosaminoglycan.
[0007] Optionally, the stepwise acid hydrolysis treatment includes the step of hydrolyzing the purified scallop skirt polysaccharide sequentially in trifluoroacetic acid at concentrations of 0.05 M, 0.2 M, 0.5 M and 2 M; The hydrolysis is performed at a temperature of 90-120℃ for 1-3 hours.
[0008] The stepwise acid hydrolysis method used in this invention is simple to operate and has obvious effects. It can significantly reduce the molecular weight while gradually removing the side-chain oligosaccharide structure that is unstable to acid, thereby preserving the stable backbone structure of the polysaccharide to a large extent.
[0009] Optionally, the anion exchange column includes Q Sepharose Fast Flow; This invention uses a Q Sepharose Fast Flow anion exchange column to rapidly separate polysaccharides, which can selectively retain acidic polysaccharide components, thereby effectively improving the purity of the final product.
[0010] The chromatographic separation includes the step of gradient elution of the scallop skirt polysaccharide using an eluent; The gradient elution uses sodium chloride solutions of 0 M, 0.2 M, and 3 M in sequence. The flow rate of the eluent is 1-3 mL / min.
[0011] Optionally, the ultrafiltration tube used is a 3000 Da ultrafiltration tube.
[0012] Optionally, the method for preparing the scallop skirt enzymatic hydrolysate includes the step of mixing scallop skirt and compound enzyme solution and then performing enzymatic hydrolysis to obtain the enzymatic hydrolysate; The composite enzyme solution includes neutral protease and composite protease; the mass ratio of neutral protease to composite protease in the composite enzyme solution is 3:1; The activity of both the neutral protease and the complex protease is 200,000 U / g; the amount of the complex enzyme solution added is 4,000 U / g (based on substrate mass).
[0013] The enzymatic hydrolysis treatment was carried out at a temperature of 50°C for 5 hours.
[0014] Optionally, the volume ratio of the scallop skirt enzymatic hydrolysate to the chlorohexadecylpyridine solution is 25:6; The mass percentage of hexadecylpyridine in the chlorohexadecylpyridine solution is 8-15%.
[0015] This invention provides scallop skirt glycosaminoglycans prepared by the above separation and purification method.
[0016] Optionally, the polysaccharide structure of the scallop skirt glycosaminoglycan includes →4)-α-D-GlcNAc6S-(1→4)-β-D-GlcA-(1→ and →3)-β-D-GalNAc6S-(1→4)-β-D-GlcA[3-O-(α-L-Fuc3S4S)]-(1→).
[0017] More preferably, the scallop skirt glycosaminoglycan includes glucosamine, glucuronic acid, galactosamine, and fucose; The molar ratio of glucosamine, glucuronic acid, galactosamine, and fucose is 0.5:0.9:1:0.2.
[0018] The scallop skirt glycosaminoglycan obtained by this invention possesses a fucoidylated chondroitin sulfate structure. This structure is frequently found in polysaccharides extracted from sea cucumbers, and this is the first time such a unique structure has been discovered in scallops. Furthermore, it exhibits typical sulfation structural characteristics, laying an important structural foundation for subsequent research on its bioactivity and structure-activity relationship. Moreover, the scallop skirt glycosaminoglycan obtained by this invention is free of nucleic acids and proteins, has high purity, good water solubility, and good pro-inflammatory activity, making it suitable for development in the pharmaceutical field and providing a new approach for the high-value utilization of shellfish.
[0019] This invention provides the application of the above-mentioned scallop skirt glycosaminoglycan in the preparation of immunomodulators.
[0020] The present invention provides an immunomodulator comprising the above-mentioned scallop skirt glycosaminoglycan.
[0021] The present invention discloses the following technical effects: This invention provides a method for separating and purifying glycosaminoglycans from scallop skirts. The steps are as follows: Scallop skirts are used as raw material for enzymatic hydrolysis. Acidic polysaccharides are selectively bound and precipitated using a quaternary ammonium salt complexation method to obtain a preliminarily separated and purified crude polysaccharide. The crude polysaccharide is then separated by anion exchange column, and the glycosaminoglycan components are collected. Further ultrafiltration membrane separation technology is used to collect the main components with uniform molecular weight. Finally, the components are desalted by dialysis and freeze-dried to obtain a high-purity scallop skirt glycosaminoglycan. The obtained glycosaminoglycan is further purified using a stepwise acid hydrolysis method to obtain a scallop skirt glycosaminoglycan containing a complex structure of heparan sulfate-like compounds and fucosylated chondroitin sulfate. This invention uses a quaternary ammonium salt complexation method to selectively remove interference from other polysaccharides, followed by ion exchange chromatography and membrane separation technology to separate and purify the target polysaccharide, obtaining an acidic glycosaminoglycan with a uniform molecular weight distribution. This avoids the problem of large amounts of coexisting acidic and neutral sugars during the traditional direct alcohol precipitation method for polysaccharide extraction, which leads to difficulties in structural analysis.
[0022] This invention is the first to identify a novel structure of fucosylated chondroitin sulfate in scallop skirt glycosaminoglycans, clarifying the sulfation site and laying a structural foundation for elucidating its pro-inflammatory activity and mechanism of action. The scallop skirt glycosaminoglycans obtained in this invention contain a fucosylated chondroitin sulfate structure, a structure frequently found in polysaccharides extracted from sea cucumbers. This is the first time this unique structure has been discovered in scallops, exhibiting typical sulfation structural characteristics, providing an important structural basis for subsequent research on bioactivity and structure-activity relationships. Furthermore, the scallop skirt glycosaminoglycans obtained in this invention are free of nucleic acids and proteins, possess high purity, good water solubility, and good pro-inflammatory activity, making them suitable for development in the pharmaceutical field and providing a new approach for the high-value utilization of shellfish.
[0023] Meanwhile, the results of specific embodiments of this invention show that the scallop skirt glycosaminoglycans provided by this invention have been proven to have good immunostimulatory activity, and are expected to become a good natural immunomodulator. Therefore, this invention is the first to isolate and purify a complex glycosaminoglycan from the marine byproduct scallop skirt. The obtained glycosaminoglycan has high purity, a novel structure, and strong immunomodulatory activity, providing a new technical path and research idea for the functional exploration and high-value utilization of active polysaccharides in scallop skirt. Attached Figure Description
[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0025] Figure 1This is an anion exchange chromatography elution curve of glycosaminoglycans from scallop skirts provided in Example 2 of the present invention; Figure 2 The infrared spectrum of the isolated and purified scallop skirt glycosaminoglycan provided in Example 3 of the present invention; Figure 3 The NMR spectra of the glycosaminoglycans after stepwise acid hydrolysis provided in Example 3 of the present invention are shown; wherein, (a) is a one-dimensional NMR and (b) is a two-dimensional NMR. Figure 4 Ultraviolet spectral analysis of scallop skirt glycosaminoglycans provided in Example 3 of this invention; Figure 5 Immunostimulatory activity analysis of the scallop skirt glycosaminoglycan isolated and purified in Example 1 of this invention; Figure 6 Flowchart for the separation and purification of glycosaminoglycans from scallop skirts. Detailed Implementation
[0026] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.
[0027] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Any stated value or intermediate value within a stated range, as well as each smaller range between any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.
[0028] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.
[0029] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be apparent to those skilled in the art. This specification and embodiments are merely exemplary.
[0030] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.
[0031] The process for separating and purifying glycosaminoglycans from scallop skirts is as follows: Figure 6 As shown in the following example, the specific steps are as follows: Example 1: Preparation of crude polysaccharide from scallop skirt The scallop skirt and a compound enzyme solution (the compound enzyme solution contained neutral protease (manufacturer: Yuanye Biotechnology Co., Ltd., product number: S10013-250g) and compound protease (manufacturer: Solarbio Technology Co., Ltd., product number: C8800-100g) with an enzyme activity of 200,000 U / g) were mixed and then subjected to enzymatic hydrolysis to obtain an enzymatic hydrolysate; the enzymatic hydrolysis was carried out at a temperature of 50℃ for 5 h, and the amount of compound enzyme solution added was 4000 U / g (based on substrate mass); Add 240 mL of 8-15 wt% hexadecyl chloride pyridine (10 wt% hexadecyl chloride pyridine was added in this example) to 1000 mL of enzymatic hydrolysate, mix well and let stand overnight, centrifuge at 8000 rpm for 15 min, collect the precipitate, add 500 mL of sodium chloride solution containing 10-20% (v / v) anhydrous ethanol (sodium chloride solution containing 15% (v / v) anhydrous ethanol was added in this example) to reconstitute, centrifuge at 8000 rpm for 15 min, collect the precipitate, add 2-4 times the volume of 95% (v / v) ethanol and precipitate overnight (2 times the volume was added in this example), dialyze through a 3000 Da dialysis bag, freeze dry at -75℃ for 24 h to obtain crude polysaccharide from scallop skirt.
[0032] Example 2 Preparation of glycosaminoglycans from scallop skirts 50 mg of the crude polysaccharide from scallop skirt prepared in Example 1 was completely dissolved in 1 mL of pure water, filtered through a 0.22 μm filter membrane, and then loaded onto a Q Sepharose Fast Flow anion exchange column. Gradient elution was performed using 0 M, 0.2 M, and 3 M NaCl solutions, with 600 mL of each solution used at a flow rate of 3 mL / min. The eluent was analyzed using the phenol-sulfuric acid method, and elution curves were plotted. The eluent fraction with the highest detected acidic sugar content, i.e., the liquid eluted from the 3 M eluent (denoted as fraction C), was collected. Figure 1 ).
[0033] The elution fraction C was ultrafiltered using an ultrafiltration tube with a molecular weight cutoff of 100 kDa, and the fractions with a molecular weight of 100 kDa or higher were collected to remove low molecular weight impurities. The upper retentate of the ultrafiltration tube was freeze-dried at -75°C for 24 h to remove moisture, thus obtaining the purified scallop skirt glycosaminoglycan product with uniform molecular weight—purified scallop skirt glycosaminoglycan.
[0034] The purified scallop skirt glycosaminoglycans were prepared into a 10 mg / mL solution, and an equal volume of 0.05 M trifluoroacetic acid was added. Hydrolysis was carried out at 90-120℃ (110℃ in this example) for 1 h. After adjusting the pH to neutral, the hydrolysate was separated by ultrafiltration through a 3000 Da ultrafiltration tube. The lower filtrate was analyzed for monosaccharide composition to obtain the hydrolysis status of polysaccharide branched oligosaccharides, gradually screening out sugars located in the core structure. Then, an equal volume of 0.2 M trifluoroacetic acid was added to the ultrafiltration retentate, and hydrolysis continued at 110℃ for 1 h. After adjusting the pH to neutral, the hydrolysate was separated by ultrafiltration through a 3000 Da ultrafiltration tube. Finally, an equal volume of 0.5 M trifluoroacetic acid was added to the ultrafiltration retentate, and hydrolysis continued at 110℃ for 1 h. After adjusting the pH to neutral, the hydrolysate was separated by ultrafiltration through a 3000 Da ultrafiltration tube. Finally, an equal volume of 2 M trifluoroacetic acid was added to the ultrafiltration retentate, and hydrolysis was continued at 110 °C for 1 h. After adjusting the pH to neutral, the hydrolysate was dialyzed through a 500 Da dialysis bag to remove salts. After freeze-drying (-75 °C for 24 h), scallop skirt glycosaminoglycans with uniform molecular weight, which are easy to analyze for their main structure, were obtained.
[0035] Example 3 Preparation of glycosaminoglycans from scallop skirts 50 mg of the crude polysaccharide from scallop skirt prepared in Example 1 was completely dissolved in 1 mL of pure water, filtered through a 0.22 μm filter membrane, and then loaded onto a Q Sepharose Fast Flow anion exchange column. Gradient elution was performed using 0 M, 0.2 M, and 3 M NaCl solutions, with 600 mL of each solution used at a flow rate of 2 mL / min. The eluent was analyzed using the phenol-sulfuric acid method, and elution curves were plotted. The eluent fraction with the highest detected acidic sugar content (denoted as fraction C) was collected.
[0036] The elution fraction C was ultrafiltered using an ultrafiltration tube with a molecular weight cutoff of 100 kDa, and the fractions with a molecular weight of 100 kDa or higher were collected to remove low molecular weight impurities. The upper retentate of the ultrafiltration tube was freeze-dried at -75°C for 24 h to remove moisture, thus obtaining the purified scallop skirt glycosaminoglycan product with uniform molecular weight—purified scallop skirt glycosaminoglycan.
[0037] The purified scallop skirt glycosaminoglycans were prepared into a 10 mg / mL solution, and an equal volume of 0.05 M trifluoroacetic acid was added. Hydrolysis was carried out at 90-120℃ (100℃ was selected in this example) for 1 h. After adjusting the pH to neutral, the hydrolysate was separated by ultrafiltration through a 3000 Da ultrafiltration tube. The lower filtrate was analyzed for monosaccharide composition to obtain the hydrolysis status of polysaccharide branched oligosaccharides, gradually screening out sugars located in the core structure. An equal volume of 0.2 M trifluoroacetic acid was added to the ultrafiltration retentate, and hydrolysis continued at 100℃ for 1 h. After adjusting the pH to neutral, the hydrolysate was separated by ultrafiltration through a 3000 Da ultrafiltration tube. Then, an equal volume of 0.5 M trifluoroacetic acid was added to the ultrafiltration retentate, and hydrolysis continued at 100℃ for 1 h. After adjusting the pH to neutral, the hydrolysate was separated by ultrafiltration through a 3000 Da ultrafiltration tube. Finally, an equal volume of 2 M trifluoroacetic acid was added to the ultrafiltration retentate, and hydrolysis was continued at 100 °C for 1 h. After adjusting the pH to neutral, the hydrolysate was dialyzed through a 500 Da dialysis bag to remove salts. After freeze-drying (-75 °C for 24 h), scallop skirt glycosaminoglycans with uniform molecular weight, which are easy to analyze for their main structure, were obtained.
[0038] Example 4: Compositional testing of glycosaminoglycans from scallop skirts Fourier transform infrared spectra of scallop skirt glycosaminoglycans obtained in Example 3 (e.g.) Figure 2 Analysis (as shown) indicates that the scallop skirt glycosaminoglycan obtained in this invention has a density of 3284 cm⁻¹. -1 The characteristic peak at 2936 cm⁻¹ represents the OH stretching vibration; -1 The characteristic peak at 1672 cm⁻¹ represents the CH stretching vibration; -1 The characteristic peak at 1545 cm⁻¹ represents the C=O stretching vibration of the carboxyl and acetyl groups. -1 The characteristic peak at 1206 cm⁻¹ represents the NH vibration of the N-acetyl group. -1 The characteristic peak at 1031 cm⁻¹ represents the S=O asymmetric stretching vibration in the sulfate ester group, and all of these correspond to typical characteristic absorption peaks of glycosaminoglycans. -1 The characteristic peak at 838 cm⁻¹ represents the COC stretching vibration, indicating a pyran ring conformation; -1 The characteristic peak at this location indicates the presence of COS symmetric stretching vibration, possibly indicating sulfation. The monosaccharide composition of the scallop skirt glycosaminoglycans isolated in Example 3 was analyzed, and the results are as follows: Figure 3 As shown, the glycosaminoglycans in the scallop skirt contain four monosaccharides: glucosamine, glucuronic acid, galactosamine, and fucose, in a molar ratio of 0.5:0.9:1:0.2. UV scanning showed no obvious absorption peaks at 260 nm and 280 nm. Figure 4This indicates that the isolated scallop skirt glycosaminoglycan has high purity and does not contain large molecular proteins and nucleic acids. The fine structure of the scallop skirt glycosaminoglycan was resolved using 1D and 2D NMR, revealing that it contains sulfated heparan sulfate and fucosylated chondroitin sulfate structures at specific sites, with structural formulas of →4)-α-D-GlcNAc6S-(1→4)-β-D-GlcA-(1→) and →3)-β-D-GalNAc6S-(1→4)-β-D-GlcA[3-O-(α-L-Fuc3S4S)]-(1→).
[0039] Example 5: Test of the pro-inflammatory activity of glycosaminoglycans from scallop skirts Take 1×10⁻⁶ RAW264.7 cells in logarithmic growth phase. 5 Cells / mL suspension were seeded at 100 μL per well in 96-well plates and incubated at 37°C for 12 h in a CO2 incubator, after which the culture medium was discarded. Using the scallop skirt glycosaminoglycan isolated in Example 3 as a sample, a stock solution of 5 mg / mL was prepared and diluted to 25 μg / mL, 50 μg / mL, 100 μg / mL, and 150 μg / mL in DMEM high-glucose medium, respectively, and added to cells in 96-well plates, labeled 25, 50, 100, and 150. Lipopolysaccharide (LPS) 1 μg / mL was used as a positive control, and a blank group (DMEM high-glucose medium) was used as a negative control. After incubation for 24 h, the supernatant was collected. The NO release was determined using the Griess method to observe its pro-inflammatory effect. The results are as follows: Figure 5 As shown. By Figure 5 As can be seen from the records, the glycosaminoglycans in the scallop skirt have good immunostimulatory activity.
[0040] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.
Claims
1. A method for separating and purifying glycosaminoglycans from scallop skirts, characterized in that, Includes the following steps: After mixing and complexing the enzymatic hydrolysate of scallop skirt with a solution of hexadecylpyridine chloride, the crude polysaccharide of scallop skirt was obtained by alcohol precipitation. The crude polysaccharide from scallop skirt was separated by anion exchange column chromatography and ultrafiltration to obtain purified scallop skirt polysaccharide. The purified scallop skirt polysaccharide was subjected to stepwise acid hydrolysis to obtain the scallop skirt glycosaminoglycan.
2. The separation and purification method according to claim 1, characterized in that, The stepwise acid hydrolysis treatment includes the step of hydrolyzing the purified scallop skirt polysaccharide sequentially in trifluoroacetic acid at concentrations of 0.05 M, 0.2 M, 0.5 M and 2 M; The hydrolysis is performed at a temperature of 90-120℃ for 1-3 hours.
3. The separation and purification method according to claim 1, characterized in that, The anion exchange column includes QSepharose Fast Flow; The chromatographic separation includes the step of gradient elution of the scallop skirt polysaccharide using an eluent; The gradient elution uses sodium chloride solutions of 0 M, 0.2 M, and 3 M in sequence. The flow rate of the eluent is 1-3 mL / min.
4. The separation and purification method according to claim 1, characterized in that, The ultrafiltration tube used is a 3000 Da ultrafiltration tube.
5. The separation and purification method according to claim 1, characterized in that, The method for preparing the scallop skirt enzymatic hydrolysate includes the steps of mixing scallop skirt and compound enzyme solution and then performing enzymatic hydrolysis to obtain the enzymatic hydrolysate. The composite enzyme solution includes neutral protease and composite protease; the mass ratio of neutral protease to composite protease in the composite enzyme solution is 3:1; The activity of both the neutral protease and the complex protease is 200,000 U / g; the amount of the complex enzyme solution added is 4,000 U / g. The enzymatic hydrolysis treatment was carried out at a temperature of 50°C for 5 hours.
6. The separation and purification method according to claim 1, characterized in that, The volume ratio of the scallop skirt enzymatic hydrolysate to the chlorohexadecylpyridine solution is 25:6; The mass percentage of hexadecylpyridine in the chlorohexadecylpyridine solution is 8-15%; The solvent used for the alcohol precipitation is ethanol.
7. Scallop skirt glycosaminoglycan prepared by the separation and purification method according to any one of claims 1-6.
8. The scallop skirt glycosaminoglycan according to claim 7, characterized in that, The polysaccharide structure of the scallop skirt glycosaminoglycan includes →4)-α-D-GlcNAc6S-(1→4)-β-D-GlcA-(1→ and →3)-β-D-GalNAc6S-(1→4)-β-D-GlcA[3-O-(α-L-Fuc3S4S)]-(1→).
9. The use of the scallop skirt glycosaminoglycan according to claim 7 or 8 in the preparation of immunomodulators.
10. An immunomodulatory agent, characterized in that, The immunomodulator includes the scallop skirt glycosaminoglycan as described in claim 7 or 8.