A process for extracting uric acid-lowering polypeptide from sunflower disk

Abstract

The invention provides a process for extracting uric acid-lowering polypeptides from sunflower disks, and belongs to the technical field of plant polypeptides. Sunflower disks are dried and crushed to obtain sunflower disk powder, the sunflower disk powder is dispersed in a mixed solvent and soaked, and then ultrasonically treated to obtain defatted sunflower disk powder, the defatted sunflower disk powder and a protein extractant are dispersed in anhydrous ethanol in an inert gas protection environment, stirred for 8 to 12 hours in an environment of 23 to 25°C, and then an intermediate product is obtained by magnetic separation, and the intermediate product is hydrolyzed by acid to obtain sunflower disk protein; alkaline protease and papain are sequentially enzymolyzed once and twice on the sunflower disk protein, centrifuged and the supernatant is retained, the supernatant is decolorized, and the sunflower disk protein hydrolyzate is obtained by centrifugal filtration and freeze drying; the sunflower disk protein hydrolyzate is separated and purified by column chromatography, and the eluate is collected and freeze-dried to obtain the uric acid-lowering polypeptide.

Description

Technical Field

[0001] The invention relates to the technical field of plant polypeptides, and in particular to a process for extracting uric acid-lowering polypeptides from sunflower disks. Background Art

[0002] Hyperuric acid is the fourth "high" metabolic disorder after hypertension, hyperglycemia, and hyperlipidemia. It is mainly caused by the imbalance of uric acid (salt) production and excretion in the human body. Long-term accumulation of urate in joints can also cause gout. Uric acid is the end product of purine metabolism in the body. When its concentration is higher than 7mg / dL (male) or 6mg / dL (female), it will cause damage to the body and can be identified as a person with hyperuricemia. Currently, the drugs used clinically are divided into three categories: inhibiting uric acid synthesis (allopurinol and febuxostat), promoting uric acid excretion (probenecid and benzbromarone) and uricase. These drugs are only allowed to be used in people with hyperuricemia who have gout and related symptoms, and will cause side effects such as liver and kidney damage. There is currently no clear intervention for asymptomatic people with hyperuricemia, but long-term hyperuricemia increases the risk of cardiovascular and kidney diseases.

[0003] As a natural plant resource, sunflower discs have been found by scientists in recent years to have potential active ingredients for lowering uric acid. By extracting active ingredients such as proteins, alkaloids, flavonoids and small molecule peptides from sunflower discs, effective treatment of hyperuricemia can be achieved. Among them, small molecule peptides, as enzyme preparations that can be directly absorbed by the intestine, have strong biological activity and can enter the blood to regulate uric acid metabolism and renal tubular transporters, thereby controlling uric acid production and increasing uric acid excretion. This discovery provides a new idea for the treatment of hyperuricemia.

[0004] In the process of extracting protein peptides from sunflower discs, the key problem faced is the low protein yield, which leads to a decrease in peptide yield and loss of peptide activity. Sunflower discs are rich in protein resources, but their complex cell structure and diverse chemical composition make effective protein extraction extremely challenging. Traditional extraction methods, such as acid-base method and solvent extraction method, often lead to low protein extraction efficiency due to imprecise control of operating conditions, such as high temperature, pH value deviating from the optimal range, and long extraction time, and a large number of valuable proteins and peptides cannot be effectively released. In addition, these unfavorable extraction conditions can easily destroy the polypeptide structure in the protein, resulting in the loss of polypeptide biological activity. This not only limits the economy and practicality of extracting protein peptides from sunflower discs, but also hinders the widespread application of biologically active polypeptides in the fields of medicine and health products.

[0005] Therefore, developing a process that can not only improve the yield of peptides extracted from sunflower discs, but also effectively protect the biological activity of the extracted peptides is of great significance for achieving in-depth development and efficient utilization of sunflower disc resources. Summary of the invention

[0006] In order to solve the problems existing in the prior art, the present invention provides a process for extracting uric acid-lowering polypeptides from sunflower discs, which not only improves the extraction efficiency of uric acid-lowering polypeptides, but also effectively maintains the biological activity of uric acid-lowering polypeptides.

[0007] To achieve the above object, the present invention adopts the following technical solution:

[0008] A process for extracting uric acid-lowering polypeptide from a sunflower disk comprises the following steps:

[0009] The sunflower disk is dried and crushed to obtain sunflower disk powder, the sunflower disk powder is dispersed in a mixed solvent, soaked and ultrasonically treated to obtain defatted sunflower disk powder, the defatted sunflower disk powder and a protein extractant are dispersed in anhydrous ethanol in an inert gas protection environment, stirred for 8 to 12 hours in an environment of 23 to 25° C., and an intermediate product is obtained by magnetic separation, and the intermediate product is hydrolyzed with acid to obtain sunflower disk protein; the sunflower disk protein is enzymatically hydrolyzed once and twice with alkaline protease and papain in sequence, centrifuged and the supernatant is retained, the supernatant is decolorized, and a sunflower disk protein hydrolyzate is obtained by centrifugal filtration and freeze drying; the sunflower disk protein hydrolyzate is separated and purified by column chromatography, and the eluate is collected and freeze-dried to obtain the uric acid-lowering polypeptide;

[0010] The preparation of the protein extractant comprises the following steps:

[0011] Disperse ferric chloride hexahydrate, ferrous chloride tetrahydrate and anhydrous ethanol in deionized water, stir for 10-20 minutes in an inert gas protection environment, adjust the pH to 10-11, and then heat to 85-55°C and stir for 1-2 hours. After the reaction is completed, magnetic separation is performed to obtain hydroxyl-modified ferrosoferric oxide; in an inert gas protection environment, disperse hydroxyl-modified ferrosoferric oxide and N-oleoylsarcosine in dichloromethane, add 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride Salt, 4-dimethylaminopyridine and triethylamine are stirred and reacted in an environment of 23-25° C. for 24-48 hours, and then N-oleoylsarcosine-modified ferroferric oxide is obtained by magnetic separation; in an inert gas protection environment, N-oleoylsarcosine-modified ferroferric oxide, citral and sodium dodecyl sulfate are dispersed in deionized water, stirred in an environment of 65-75° C. for 20-40 minutes, and then benzoyl peroxide is added, the temperature is raised to 80-85° C., and the reaction is stirred for 5-7 hours to obtain the protein extractant.

[0012] Furthermore, the weight ratio of the ferric chloride hexahydrate, ferrous chloride tetrahydrate and anhydrous ethanol is 1:0.3~0.5:0.1~0.3.

[0013] Furthermore, the weight ratio of the hydroxyl-modified ferrosoferric oxide to N-oleoylsarcosine is 1:0.2-0.4.

[0014] Furthermore, the weight ratio of the hydroxyl-modified ferrosoferric oxide, 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride, 4-dimethylaminopyridine and triethylamine is 1: 0.018-0.024: 0.053-0.071: 0.042-0.056.

[0015] Furthermore, the weight ratio of the N-oleoylsarcosine-modified ferroferric oxide, citral and sodium dodecyl sulfate is 81-82:1.4-1.6:25-40.

[0016] Furthermore, the weight ratio of the benzoyl peroxide to the N-oleoylsarcosine-modified ferrosoferric oxide is 0.01-0.1:1.

[0017] Furthermore, the ultrasonic treatment time is 15 to 30 minutes.

[0018] Furthermore, the weight ratio of the defatted sunflower disk powder, the protein extractant and the anhydrous ethanol is 1:25~35:30~50.

[0019] Furthermore, the conditions of the acid hydrolysis include a hydrolysis pH of 4-5, a hydrolysis temperature of 40-60° C., and a hydrolysis time of 6-8 h.

[0020] Furthermore, the weight ratio of the sunflower disc protein to deionized water is 1:100.

[0021] Furthermore, the weight ratio of the alkaline protease to deionized water is 0.6-1.4:100.

[0022] Preferably, the weight ratio of the alkaline protease to deionized water is 1:100.

[0023] Furthermore, the enzyme activity of the alkaline protease is 9000 U / g.

[0024] Furthermore, the conditions of the primary enzymatic hydrolysis include an enzymatic hydrolysis pH of 7-11, an enzymatic hydrolysis temperature of 45-65° C., and an enzymatic hydrolysis time of 1.5-3 h.

[0025] Preferably, the conditions for the primary enzymatic hydrolysis are as follows: the enzymatic hydrolysis pH is 9, the enzymatic hydrolysis temperature is 50° C., and the enzymatic hydrolysis time is 2.5 h.

[0026] Furthermore, the weight ratio of the papain to the primary enzymatic hydrolysis solution is 0.4:100.

[0027] Furthermore, the enzyme activity of the papain is 9000 U / g.

[0028] Furthermore, the conditions of the secondary enzymolysis include an enzymolysis pH of 6.9-7.1, an enzymolysis temperature of 37-45° C., and an enzymolysis time of 2.5-3 h.

[0029] Preferably, the conditions for the secondary enzymolysis are enzymolysis pH of 7, enzymolysis temperature of 45° C. and enzymolysis time of 3 h.

[0030] Furthermore, the decolorization treatment conditions include a decolorization pH of 2-3, a decolorization temperature of 45-55° C., and a decolorization time of 0.5-1.5 h.

[0031] Furthermore, the mixed solvent is prepared by mixing n-hexane and anhydrous ethanol in a weight ratio of 1:1.

[0032] Furthermore, the inert gas is nitrogen.

[0033] Furthermore, the filler is dextran gel G-50.

[0034] Furthermore, the flow rate of the loading is 0.25~0.3mL / min.

[0035] Furthermore, the elution flow rate is 0.25-0.3 mL / min.

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

[0037] (1) The surface of the hydroxyl-modified ferroferric oxide prepared by the present invention contains hydroxyl groups, which can react chemically with the carboxyl group of N-oleoylsarcosine, so that N-oleoylsarcosine is adsorbed on the surface of the hydroxyl-modified ferroferric oxide. Citral reacts with the double bond of N-oleoylsarcosine through copolymerization to obtain a protein extractant. The aldehyde group on the surface of the protein extractant forms an imine structure with the amino group in the sunflower disc protein. The sunflower disc protein and the protein extractant are extracted from the solvent by magnetic separation. The imine structure can be hydrolyzed again to restore the original aldehyde group and amino group after acid hydrolysis, thereby realizing the separation of the sunflower disc protein and the protein extractant.

[0038] (2) One end of N-oleoylsarcosine is adsorbed on the surface of hydroxyl-modified ferroferric oxide, and the long chain hydrocarbon forms a steric hindrance, which can prevent the hydroxyl-modified ferroferric oxide from agglomerating, and is helpful to form a stable dispersion system. Citral can further prevent the leakage of hydroxyl-modified ferroferric oxide by copolymerizing with the double bonds in N-oleoylsarcosine. The protein extractant synthesized by the present invention has good recyclability and can be reused after proper washing, thereby avoiding waste of resources.

[0039] (3) Through the results of the content detection and activity test of the uric acid-lowering polypeptide, it can be found that the process provided by the present invention not only improves the extraction efficiency of the uric acid-lowering polypeptide, but also retains the good biological activity of the uric acid-lowering polypeptide. DETAILED DESCRIPTION

[0040] The technical solution of the present invention will be clearly and completely described below through the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0041] Unless otherwise specified, the raw materials and reagents used in the present invention are commercially available or can be prepared by known methods.

[0042] Preparation Example 1:

[0043] The preparation of the mixed solvent comprises the following steps:

[0044] 100 parts by weight of n-hexane and 100 parts by weight of anhydrous ethanol were stirred and mixed for 5 minutes to prepare a mixed solvent.

[0045] Preparation Example 2:

[0046] The preparation of the protein extractant comprises the following steps:

[0047] Disperse 50 parts by weight of ferric chloride hexahydrate, 15 parts by weight of ferrous chloride tetrahydrate and 5 parts by weight of anhydrous ethanol in 100 parts by weight of deionized water, stir for 10 minutes in a nitrogen atmosphere, adjust the pH to 10, heat to 85°C and stir for 1-2 hours, and after the reaction is completed, obtain hydroxyl-modified ferrosoferric oxide by magnetic separation; in a nitrogen atmosphere, disperse 100 parts by weight of hydroxyl-modified ferrosoferric oxide and 20 parts by weight of N-oleoylsarcosine in 200 parts by weight of dichloromethane, add 1.8 parts by weight of 1-ethyl-(3-dimethylaminopropyl) Carbodiimide hydrochloride, 5.3 parts by weight of 4-dimethylaminopyridine and 4.2 parts by weight of triethylamine are stirred and reacted at 23°C for 24 hours, and then N-oleoylsarcosine-modified ferrosoferric oxide is obtained by magnetic separation; in a nitrogen protection environment, 81 parts by weight of N-oleoylsarcosine-modified ferrosoferric oxide, 1.4 parts by weight of citral and 25 parts by weight of sodium dodecyl sulfate are dispersed in 100 parts by weight of deionized water, stirred at 65°C for 20 minutes, and then 0.81 parts by weight of benzoyl peroxide are added, and the temperature is raised to 80°C and stirred for 5 hours to obtain a protein extractant.

[0048] Preparation Example 3:

[0049] The preparation of the protein extractant comprises the following steps:

[0050] 50 parts by weight of ferric chloride hexahydrate, 20 parts by weight of ferrous chloride tetrahydrate and 10 parts by weight of anhydrous ethanol were dispersed in 200 parts by weight of deionized water, stirred for 15 minutes in a nitrogen atmosphere, and then the pH was adjusted to 10.5, and then the temperature was raised to 90°C and stirred for 1.5 hours. After the reaction was completed, hydroxyl-modified ferrosilicate was obtained by magnetic separation; in a nitrogen atmosphere, 100 parts by weight of hydroxyl-modified ferrosilicate and 30 parts by weight of N-oleoylsarcosine were dispersed in 200 parts by weight of dichloromethane, and 2 parts by weight of 1-ethyl-(3-dimethylaminopropyl) carbonyl were added. Diimine hydrochloride, 6 parts by weight of 4-dimethylaminopyridine and 4.5 parts by weight of triethylamine are stirred and reacted at 23°C for 36 hours, and then N-oleoylsarcosine-modified ferrosoferric oxide is obtained by magnetic separation; in a nitrogen-protected environment, 81.5 parts by weight of N-oleoylsarcosine-modified ferrosoferric oxide, 1.5 parts by weight of citral and 30 parts by weight of sodium dodecyl sulfate are dispersed in 100 parts by weight of deionized water, stirred at 70°C for 30 minutes, and then 3.26 parts by weight of benzoyl peroxide are added, and the temperature is raised to 82°C and stirred for 6 hours to obtain a protein extractant.

[0051] Preparation Example 4:

[0052] The preparation of the protein extractant comprises the following steps:

[0053] 50 parts by weight of ferric chloride hexahydrate, 20 parts by weight of ferrous chloride tetrahydrate and 15 parts by weight of anhydrous ethanol were dispersed in 200 parts by weight of deionized water, stirred for 17 minutes in a nitrogen atmosphere, and then the pH was adjusted to 10.8, and then the temperature was raised to 85°C and stirred for 1.7 hours. After the reaction was completed, hydroxyl-modified ferrosoferric oxide was obtained by magnetic separation; in a nitrogen atmosphere, 100 parts by weight of hydroxyl-modified ferrosoferric oxide and 35 parts by weight of N-oleoylsarcosine were dispersed in 200 parts by weight of dichloromethane, and 2.2 parts by weight of 1-ethyl-(3-dimethylaminopropyl) carbonyl were added. Diimine hydrochloride, 6.5 parts by weight of 4-dimethylaminopyridine and 5 parts by weight of triethylamine are stirred and reacted at 24°C for 48 hours, and then N-oleoylsarcosine-modified ferrosoferric oxide is obtained by magnetic separation; in a nitrogen protection environment, 81.2 parts by weight of N-oleoylsarcosine-modified ferrosoferric oxide, 1.5 parts by weight of citral and 35 parts by weight of sodium dodecyl sulfate are dispersed in 100 parts by weight of deionized water, stirred at 70°C for 25 minutes, and then 4.06 parts by weight of benzoyl peroxide are added, and the temperature is raised to 83°C and stirred for 6 hours to obtain the protein extractant.

[0054] Preparation Example 5:

[0055] The preparation of the protein extractant comprises the following steps:

[0056] 50 parts by weight of ferric chloride hexahydrate, 25 parts by weight of ferrous chloride tetrahydrate and 15 parts by weight of anhydrous ethanol were dispersed in 200 parts by weight of deionized water, stirred for 20 minutes in a nitrogen atmosphere, and then the pH was adjusted to 11, and then the temperature was raised to 95°C and stirred for 2 hours. After the reaction was completed, hydroxyl-modified ferrosoferric oxide was obtained by magnetic separation. In a nitrogen atmosphere, 100 parts by weight of hydroxyl-modified ferrosoferric oxide and 40 parts by weight of N-oleoylsarcosine were dispersed in 300 parts by weight of dichloromethane, and 2.4 parts by weight of 1-ethyl-(3-dimethylaminopropyl)carbodiimide were added. Imine hydrochloride, 7.1 parts by weight of 4-dimethylaminopyridine and 5.6 parts by weight of triethylamine are stirred and reacted at 25° C. for 48 hours, and then N-oleoylsarcosine-modified ferrosoferric oxide is obtained by magnetic separation; in a nitrogen protection environment, 82 parts by weight of N-oleoylsarcosine-modified ferrosoferric oxide, 1.6 parts by weight of citral and 40 parts by weight of sodium dodecyl sulfate are dispersed in 100 parts by weight of deionized water, stirred at 75° C. for 40 minutes, and then 8.2 parts by weight of benzoyl peroxide are added, and the temperature is raised to 85° C. and stirred and reacted for 7 hours to obtain the protein extractant.

[0057] Embodiment 1:

[0058] A process for extracting uric acid-lowering polypeptide from sunflower comprises the following steps:

[0059] The sunflower disk is dried in the sun and then crushed, and the sunflower disk powder is obtained by screening with a 40-mesh sieve. 10 parts by weight of the sunflower disk powder is dispersed in the mixed solvent prepared in Preparation Example 1, soaked for 9 hours, and then ultrasonically treated for 15 minutes to obtain defatted sunflower disk powder. In a nitrogen-protected environment, 1 part by weight of the defatted sunflower disk powder and 25 parts by weight of the protein extractant prepared in Preparation Example 2 are dispersed in 30 parts by weight of anhydrous ethanol, stirred for 8 hours at 23° C., and then magnetically separated to obtain an intermediate product. The intermediate product is dispersed in deionized water, adjusted to pH 4, and then hydrolyzed at 40° C. for 6 hours. The protein extractant and the reaction solution are obtained by magnetic separation, and the reaction solution is freeze-dried to obtain sunflower disk protein.

[0060] 2 parts by weight of sunflower disc protein were dispersed in 200 parts by weight of deionized water, heated to 95°C and stirred for 8 min, then cooled to 23°C, 0.6 parts by weight of alkaline protease with an enzyme activity of 9000 U / g was added to adjust the pH to 7, the sunflower disc protein was subjected to a primary enzymolysis in an environment of 45°C for 1.5 h, the supernatant was collected by centrifugation at a speed of 6000 rpm for 10 min to obtain a primary enzymolysis solution, 0.4 parts by weight of papain with an enzyme activity of 9000 U / g was added to 100 parts by weight of the primary enzymolysis solution to adjust the pH to 6.9, and the mixture was stirred for 10 min. The secondary enzymolysis was carried out at 37°C for 2.5 hours, and the supernatant was collected by centrifugation to obtain a secondary enzymolysis solution. The secondary enzymolysis solution was stirred at 95°C for 10 minutes, cooled to 23°C, and centrifuged at 6000 rpm for 10 minutes to collect the supernatant to obtain a secondary enzymolysis product. 1.5% activated carbon was added and the pH was adjusted to 2. The secondary enzymolysis product was decolorized at 45°C for 0.5 hours. After the decolorization, it was centrifuged at 6000 rpm for 10 minutes, the pH was adjusted to 7.3, and freeze-dried to obtain a sunflower disc protein hydrolysate.

[0061] The chromatography column (1.6×20cm) was fixed vertically and the water outlet of the chromatography column was closed. After the polysaccharide gel G-50 was swollen with distilled water for 3h, the bubbles in the filler were removed by ultrasonic treatment at 200W for 15min at 23℃, and then added to the chromatography column. It was allowed to settle to a fixed height and then stand for 9h. The chromatography column was balanced with pure water before use, and the injection was started after the pH of the system and the column volume were stable. 25mg / mL of sunflower disc protein hydrolysate was loaded at a flow rate of 0.25mL / min. After loading, double distilled water was used for elution at a flow rate of 0.25mL / min. The eluate between 180 and 300min was collected and freeze-dried to obtain the uric acid-lowering polypeptide.

[0062] Embodiment 2:

[0063] A process for extracting uric acid-lowering polypeptide from sunflower comprises the following steps:

[0064] The sunflower disk is dried in the sun and then crushed, and the sunflower disk powder is obtained by screening with a 40-mesh sieve. 10 parts by weight of the sunflower disk powder is dispersed in the mixed solvent prepared in Preparation Example 1, soaked for 10 hours, and then ultrasonically treated for 25 minutes to obtain defatted sunflower disk powder. In a nitrogen-protected environment, 1 part by weight of the defatted sunflower disk powder and 30 parts by weight of the protein extractant prepared in Preparation Example 3 are dispersed in 40 parts by weight of anhydrous ethanol, stirred for 10 hours in an environment of 24° C., and then magnetically separated to obtain an intermediate product. The intermediate product is dispersed in deionized water, adjusted to pH 4.5, and then hydrolyzed in an environment of 50° C. for 7 hours, and the protein extractant and the reaction solution are obtained by magnetic separation. The reaction solution is freeze-dried to obtain sunflower disk protein.

[0065] 2 parts by weight of sunflower disc protein were dispersed in 200 parts by weight of deionized water, heated to 97°C and stirred for 9 minutes, then cooled to 24°C, 1 part by weight of alkaline protease with an enzyme activity of 9000 U / g was added to adjust the pH to 8, and the sunflower disc protein was subjected to a primary enzymolysis in an environment of 50°C for 2 hours, and the supernatant was collected by centrifugation at a speed of 7000 rpm for 15 minutes to obtain a primary enzymolysis solution, 0.4 parts by weight of papain with an enzyme activity of 9000 U / g was added to 100 parts by weight of the primary enzymolysis solution to adjust the pH to 6.9, and the mixture was stirred at 4 °C for 15 minutes. The secondary enzymolysis was carried out in a 0°C environment for 2.7 hours, and the supernatant was collected by centrifugation to obtain a secondary enzymolysis solution. The secondary enzymolysis solution was stirred in a 96°C environment for 12 minutes, cooled to 24°C, and centrifuged at 7000 rpm for 15 minutes to collect the supernatant to obtain a secondary enzymolysis product. After adding 2% activated carbon, the pH was adjusted to 2.5, and the secondary enzymolysis product was decolorized in a 47°C environment for 1 hour. After the decolorization treatment, it was centrifuged at 7000 rpm for 15 minutes, the pH was adjusted to 7.5, and freeze-dried to obtain a sunflower disc protein hydrolysate.

[0066] The chromatography column (1.6×20cm) was fixed vertically and the water outlet of the chromatography column was closed. After the polysaccharide gel G-50 was swollen with distilled water for 3.5h, the bubbles in the filler were removed by ultrasonic treatment at 200W for 17min at 24℃, and then added to the chromatography column. It was allowed to settle to a fixed height and then stand for 10h. The chromatography column was balanced with pure water before use, and the injection was started after the pH of the system and the column volume were stable. 27mg / mL of sunflower disc protein hydrolysate was loaded at a flow rate of 0.28mL / min. After loading, double distilled water was used for elution at a flow rate of 0.28mL / min. The eluate between 180 and 300min was collected and freeze-dried to obtain the uric acid-lowering polypeptide.

[0067] Embodiment 3:

[0068] A process for extracting uric acid-lowering polypeptide from sunflower comprises the following steps:

[0069] The sunflower disk is dried in the sun and then crushed, and the sunflower disk powder is obtained by screening with a 40-mesh sieve. 10 parts by weight of the sunflower disk powder is dispersed in the mixed solvent prepared in Preparation Example 1, soaked for 10.5 hours, and then ultrasonically treated for 20 minutes to obtain defatted sunflower disk powder. In a nitrogen protection environment, 1 part by weight of the defatted sunflower disk powder and 32 parts by weight of the protein extractant prepared in Preparation Example 4 are dispersed in 45 parts by weight of anhydrous ethanol, stirred for 8 hours at 24° C., and then magnetically separated to obtain an intermediate product. The intermediate product is dispersed in deionized water, adjusted to pH 4, and then hydrolyzed at 55° C. for 6.5 hours. The protein extractant and the reaction solution are obtained by magnetic separation, and the reaction solution is freeze-dried to obtain sunflower disk protein.

[0070] 2 parts by weight of sunflower disc protein were dispersed in 200 parts by weight of deionized water, heated to 97°C and stirred for 9 minutes, then cooled to 24°C, 1.4 parts by weight of alkaline protease with an enzyme activity of 9000 U / g was added to adjust the pH to 11, and the sunflower disc protein was subjected to a primary enzymolysis in an environment of 65°C for 3 hours, and the supernatant was collected by centrifugation at a speed of 6000 rpm for 20 minutes to obtain a primary enzymolysis solution, 0.4 parts by weight of papain with an enzyme activity of 9000 U / g was added to 100 parts by weight of the primary enzymolysis solution to adjust the pH to 7.1, and the mixture was stirred at 4 °C for 3 hours. The secondary enzymolysis was carried out in a 5°C environment for 2.5 hours, and the supernatant was collected by centrifugation to obtain a secondary enzymolysis solution. The secondary enzymolysis solution was stirred in a 95°C environment for 10 minutes, cooled to 23°C, and centrifuged at a speed of 6000 rpm for 20 minutes to collect the supernatant to obtain a secondary enzymolysis product. After adding 2.5% activated carbon, the pH was adjusted to 2.5, and the secondary enzymolysis product was decolorized in a 55°C environment for 1 hour. After the decolorization treatment, it was centrifuged at a speed of 6000 rpm for 20 minutes, the pH was adjusted to 7.5, and freeze-dried to obtain a sunflower disc protein hydrolysate.

[0071] The chromatography column (1.6×20cm) was fixed vertically and the water outlet of the chromatography column was closed. After the polysaccharide gel G-50 was swollen with distilled water for 3.5h, the bubbles in the filler were removed by ultrasonic treatment at 200W for 20min at 24℃, and then added to the chromatography column. It was allowed to settle to a fixed height and then stand for 10h. The chromatography column was balanced with pure water before use, and the injection was started after the pH of the system and the column volume were stable. 30mg / mL of sunflower disc protein hydrolysate was loaded at a flow rate of 0.3mL / min. After loading, double distilled water was used for elution at a flow rate of 0.3mL / min. The eluate between 180 and 300min was collected and freeze-dried to obtain the uric acid-lowering polypeptide.

[0072] Embodiment 4:

[0073] A process for extracting uric acid-lowering polypeptide from sunflower comprises the following steps:

[0074] The sunflower disk is dried in the sun and then crushed, and the sunflower disk powder is obtained by screening with a 40-mesh sieve. 10 parts by weight of the sunflower disk powder is dispersed in the mixed solvent prepared in Preparation Example 1, soaked for 11 hours, and then ultrasonically treated for 30 minutes to obtain defatted sunflower disk powder. In a nitrogen-protected environment, 1 part by weight of the defatted sunflower disk powder and 35 parts by weight of the protein extractant prepared in Preparation Example 5 are dispersed in 50 parts by weight of anhydrous ethanol, stirred for 12 hours at 25° C., and then magnetically separated to obtain an intermediate product. The intermediate product is dispersed in deionized water, adjusted to pH 5, and then hydrolyzed at 60° C. for 8 hours, and the protein extractant and reaction solution are obtained by magnetic separation. The reaction solution is freeze-dried to obtain sunflower disk protein.

[0075] 2 parts by weight of sunflower disc protein were dispersed in 200 parts by weight of deionized water, heated to 100° C. and stirred for 10 min, then cooled to 25° C., 1 part by weight of alkaline protease with an enzyme activity of 9000 U / g was added to adjust the pH to 9, and the sunflower disc protein was subjected to a primary enzymolysis in an environment of 50° C. for 2.5 h, and the supernatant was collected by centrifugation at a speed of 8000 rpm for 20 min to obtain a primary enzymolysis solution, and 0.4 parts by weight of papain with an enzyme activity of 9000 U / g was added to 100 parts by weight of the primary enzymolysis solution to adjust the pH to 7, and then the mixture was stirred for 2 hours. The secondary enzymolysis was carried out at 45°C for 3 hours, and the supernatant was collected by centrifugation to obtain a secondary enzymolysis solution. The secondary enzymolysis solution was stirred at 100°C for 10 minutes, cooled to 25°C, and centrifuged at 8000 rpm for 20 minutes to collect the supernatant to obtain a secondary enzymolysis product. After adding 3% activated carbon, the pH was adjusted to 3, and the secondary enzymolysis product was decolorized at 50°C for 1.5 hours. After the decolorization treatment, the product was centrifuged at 8000 rpm for 20 minutes, the pH was adjusted to 7.7, and freeze-dried to obtain a sunflower disc protein hydrolysate.

[0076] The chromatography column (1.6×20cm) was fixed vertically and the water outlet of the chromatography column was closed. After the polysaccharide gel G-50 was swollen with distilled water for 4 hours, the bubbles in the filler were removed by ultrasonic treatment at 200W for 20 minutes at 25°C, and then added to the chromatography column. It was allowed to settle to a fixed height and then stand for 11 hours. The chromatography column was balanced with pure water before use, and the injection was started after the pH of the system and the column volume were stable. 30mg / mL of sunflower disc protein hydrolysate was loaded at a flow rate of 0.3mL / min. After loading, double distilled water was used for elution at a flow rate of 0.3mL / min. The eluate between 180 and 300min was collected and freeze-dried to obtain the uric acid-lowering polypeptide.

[0077] Comparative Example 1:

[0078] A process for extracting uric acid-lowering polypeptide from sunflower comprises the following steps:

[0079] The papain in Example 4 was replaced by pepsin, the enzymatic hydrolysis pH was adjusted to 3, the enzymatic hydrolysis temperature was adjusted to 37° C., and the other operations were consistent with Example 4.

[0080] Comparative Example 2:

[0081] A process for extracting uric acid-lowering polypeptide from sunflower comprises the following steps:

[0082] The papain in Example 4 was replaced by trypsin, the enzymatic hydrolysis pH was adjusted to 8, the enzymatic hydrolysis temperature was adjusted to 37° C., and the other operations were consistent with Example 4.

[0083] Comparative Example 3:

[0084] A process for extracting uric acid-lowering polypeptide from sunflower comprises the following steps:

[0085] The papain in Example 4 was replaced by alkaline protease, the enzymatic hydrolysis pH of the first enzymatic hydrolysis was adjusted to 8, the enzymatic hydrolysis temperature was adjusted to 50° C., and the other operations were consistent with Example 4.

[0086] Comparative Example 4:

[0087] A process for extracting uric acid-lowering polypeptide from sunflower comprises the following steps:

[0088] The sunflower disk is dried in the sun and then crushed, and the sunflower disk powder is obtained by screening with a 40-mesh sieve. 10 parts by weight of the sunflower disk powder is dispersed in the mixed solvent prepared in Preparation Example 1, soaked for 11 hours, and then ultrasonically treated for 30 minutes to obtain defatted sunflower disk powder. In a nitrogen-protected environment, 1 part by weight of the defatted sunflower disk powder and 35 parts by weight of the protein extractant prepared in Preparation Example 5 are dispersed in 50 parts by weight of anhydrous ethanol, stirred for 12 hours at 25° C., and then magnetically separated to obtain an intermediate product. The intermediate product is dispersed in deionized water, adjusted to pH 5, and then hydrolyzed at 60° C. for 8 hours, and the protein extractant and reaction solution are obtained by magnetic separation. The reaction solution is freeze-dried to obtain sunflower disk protein.

[0089] Disperse 2 parts by weight of sunflower disc protein in 200 parts by weight of deionized water, heat to 100°C, stir for 10 minutes, and then cool to 25°C, add 1 part by weight of alkaline protease with an enzyme activity of 9000U / g to adjust the pH to 9, react in a 50°C environment for 2.5 hours to enzymolyze the sunflower disc protein, centrifuge at 8000rpm for 20 minutes to collect the supernatant to obtain an enzymolyzate, stir the enzymolyzate in a 100°C environment for 10 minutes, cool to 25°C, centrifuge at 8000rpm for 20 minutes to collect the supernatant to obtain an enzymolyzate, add 3% activated carbon, adjust the pH to 3, and then decolorize the enzymolyzate in a 50°C environment for 1.5 hours, centrifuge at 8000rpm for 20 minutes after the decolorization, adjust the pH to 7.7, and freeze-dry to obtain a sunflower disc protein hydrolyzate;

[0090] The chromatography column (1.6×20cm) was fixed vertically and the water outlet of the chromatography column was closed. After the polysaccharide gel G-50 was swollen with distilled water for 4 hours, the bubbles in the filler were removed by ultrasonic treatment at 200W for 20 minutes at 25°C, and then added to the chromatography column. It was allowed to settle to a fixed height and then stand for 11 hours. The chromatography column was balanced with pure water before use, and the injection was started after the pH of the system and the column volume were stable. 30mg / mL of sunflower disc protein hydrolysate was loaded at a flow rate of 0.3mL / min. After loading, double distilled water was used for elution at a flow rate of 0.3mL / min. The eluate between 180 and 300min was collected and freeze-dried to obtain the uric acid-lowering polypeptide.

[0091] Comparative Example 5:

[0092] A process for extracting uric acid-lowering polypeptide from sunflower comprises the following steps:

[0093] The sunflower disk is dried in the sun and then crushed, and the sunflower disk powder is obtained by screening with a 40-mesh sieve. 10 parts by weight of the sunflower disk powder is dispersed in the mixed solvent prepared in Preparation Example 1, soaked for 11 hours, and then ultrasonically treated for 30 minutes to obtain defatted sunflower disk powder. In a nitrogen protection environment, 1 part by weight of the defatted sunflower disk powder and 35 parts by weight of the protein extractant prepared in Preparation Example 5 are dispersed in 50 parts by weight of anhydrous ethanol, stirred at 25° C. for 12 hours, and then magnetically separated to obtain an intermediate product. The intermediate product is dispersed in deionized water and the pH is adjusted to 5, and then hydrolyzed at 60° C. for 8 hours, and the protein extractant and the reaction solution are obtained by magnetic separation. The reaction solution is freeze-dried to obtain sunflower disk protein.

[0094] Disperse 2 parts by weight of sunflower disc protein in 200 parts by weight of deionized water, heat to 100°C, stir for 10 minutes, and then cool to 25°C, add 1 part by weight of 0.4 parts by weight of papain with an enzyme activity of 9000U / g, adjust the pH to 7, react in a 45°C environment for 3 hours for enzymolysis, collect the supernatant by centrifugation to obtain an enzymolysis solution, stir the enzymolysis solution in a 100°C environment for 10 minutes, cool to 25°C, centrifuge at 8000rpm for 20 minutes to collect the supernatant to obtain an enzymolysis product, add 3% activated carbon, adjust the pH to 3, and then decolorize the enzymolysis product in a 50°C environment for 1.5 hours, centrifuge at 8000rpm for 20 minutes after the decolorization, adjust the pH to 7.7, and freeze-dry to obtain a sunflower disc protein hydrolysate;

[0095] The chromatography column (1.6×20cm) was fixed vertically and the water outlet of the chromatography column was closed. After the polysaccharide gel G-50 was swollen with distilled water for 4 hours, the bubbles in the filler were removed by ultrasonic treatment at 200W for 20 minutes at 25°C, and then added to the chromatography column. It was allowed to settle to a fixed height and then stand for 11 hours. The chromatography column was balanced with pure water before use, and the injection was started after the pH of the system and the column volume were stable. 30mg / mL of sunflower disc protein hydrolysate was loaded at a flow rate of 0.3mL / min. After loading, double distilled water was used for elution at a flow rate of 0.3mL / min. The eluate between 180 and 300min was collected and freeze-dried to obtain the uric acid-lowering polypeptide.

[0096] Comparative Example 6:

[0097] A process for extracting uric acid-lowering polypeptide from sunflower comprises the following steps:

[0098] The sunflower disk is dried in the sun and then crushed, and the powder is screened through a 40-mesh sieve to obtain sunflower disk powder. 10 parts by weight of the sunflower disk powder is dispersed in 100 parts by weight of the mixed solvent prepared in Preparation Example 1 and soaked for 11 hours to obtain defatted sunflower disk powder, and then 100 parts by weight of deionized water are added, stirred and extracted for 12 hours, and then centrifuged, and the supernatant is retained by vacuum filtration, and 180.5 parts by weight of ammonium sulfate is added to 50 parts by weight of the supernatant, stirred for 30 minutes, and then precipitated for 10 hours, and the precipitate is collected by centrifugation, redissolved, dialyzed, and freeze-dried to obtain sunflower disk protein;

[0099] 2 parts by weight of sunflower disc protein were dispersed in 200 parts by weight of deionized water, heated to 100° C. and stirred for 10 min, then cooled to 25° C., 1 part by weight of alkaline protease with an enzyme activity of 9000 U / g was added to adjust the pH to 9, and the sunflower disc protein was subjected to a primary enzymolysis in an environment of 50° C. for 2.5 h, and the supernatant was collected by centrifugation at a speed of 8000 rpm for 20 min to obtain a primary enzymolysis solution, and 0.4 parts by weight of papain with an enzyme activity of 9000 U / g was added to 100 parts by weight of the primary enzymolysis solution to adjust the pH to 7, and then the mixture was stirred for 2 hours. The secondary enzymolysis was carried out at 45°C for 3 hours, and the supernatant was collected by centrifugation to obtain a secondary enzymolysis solution. The secondary enzymolysis solution was stirred at 100°C for 10 minutes, cooled to 25°C, and centrifuged at 8000 rpm for 20 minutes to collect the supernatant to obtain a secondary enzymolysis product. After adding 3% activated carbon, the pH was adjusted to 3, and the secondary enzymolysis product was decolorized at 50°C for 1.5 hours. After the decolorization treatment, the product was centrifuged at 8000 rpm for 20 minutes, the pH was adjusted to 7.7, and freeze-dried to obtain a sunflower disc protein hydrolysate.

[0100] The chromatography column (1.6×20cm) was fixed vertically and the water outlet of the chromatography column was closed. After the polysaccharide gel G-50 was swollen with distilled water for 4 hours, the bubbles in the filler were removed by ultrasonic treatment at 200W for 20 minutes at 25°C, and then added to the chromatography column. It was allowed to settle to a fixed height and then stand for 11 hours. The chromatography column was balanced with pure water before use, and the injection was started after the pH of the system and the column volume were stable. 30mg / mL of sunflower disc protein hydrolysate was loaded at a flow rate of 0.3mL / min. After loading, double distilled water was used for elution at a flow rate of 0.3mL / min. The eluate between 180 and 300min was collected and freeze-dried to obtain the uric acid-lowering polypeptide.

[0101] Comparative Example 7:

[0102] A process for extracting uric acid-lowering polypeptide from sunflower comprises the following steps:

[0103] The sunflower disks were dried in the sun and then crushed, and sieved through a 40-mesh sieve to obtain sunflower disk powder, 10 parts by weight of the sunflower disk powder were dispersed in 80 parts by weight of deionized water, the pH was adjusted to 9 with sodium hydroxide, and ultrasonic extraction was performed at an ultrasonic power of 200 W in an environment of 55° C. for 2 h to obtain a sunflower disk protein isolate liquid;

[0104] The sunflower disc protein isolate solution obtained above was heated in an environment of 90° C. for 20 minutes and then cooled to 40° C., and then 1 weight portion of alkaline protease with an enzyme activity of 9000 U / g was added to adjust the pH to 9, and the solution was reacted in an environment of 50° C. for 2.5 hours. After the reaction was completed, the solution was centrifuged at a speed of 8000 rpm for 20 minutes to obtain a sunflower disc protein hydrolysate;

[0105] The above-obtained sunflower disc protein hydrolysate is filtered through a ceramic membrane with a molecular weight cutoff of 2000000Da, and the intermediate clear liquid is taken, and the intermediate clear liquid is ultrafiltered through an ultrafiltration membrane with a molecular weight cutoff of 1500Da to obtain a filtrate with a molecular weight less than 1500Da, and the filtrate is concentrated to a quarter of its original volume, and spray-dried to obtain a sunflower disc oligopeptide uric acid-lowering polypeptide.

[0106] Test Example 1:

[0107] The uric acid-lowering polypeptides obtained in Examples 1 to 4 and Comparative Examples 1 to 7 were determined by high performance liquid chromatography to determine the content of the uric acid-lowering polypeptides in the products, wherein Comparative Example 7 was a uric acid-lowering polypeptide extracted from a sunflower disc by prior art, and the determination results are shown in Table 1.

[0108] Table 1. Uric acid-lowering polypeptide content in the products of Examples 1 to 4 and Comparative Examples 1 to 7

[0109]

[0110] As shown in Table 1, the content of uric acid-lowering polypeptide in the product obtained by Example 1~4 is higher than the content of uric acid-lowering polypeptide in the product obtained by Comparative Example 1~6. By comparing Example 1~4 with Comparative Example 6, it is illustrated that the protein extractant synthesized by the present invention is stronger than ammonium sulfate salting out to extract sunflower disc protein for the extraction effect of sunflower disc protein, and effectively promotes the extraction, separation and purification of uric acid-lowering polypeptide in the subsequent process. By comparing Example 1~4 with Comparative Example 1~5, it is illustrated that alkaline protease and papain are twice enzymolyzed to improve the yield of uric acid-lowering polypeptide. By comparing Example 1~4 with Comparative Example 7, it is illustrated that the process method provided by the present invention can effectively extract uric acid-lowering polypeptide from sunflower disc compared with the prior art.

[0111] Test Example 2: Xanthine oxidase inhibition rate of uric acid-lowering polypeptide

[0112] The xanthine oxidase inhibition rate (XOI) of the uric acid-lowering polypeptides prepared in Examples 1 to 4 and Comparative Examples 1 to 7 was measured, wherein Comparative Example 7 was a uric acid-lowering polypeptide extracted from a sunflower disc by the prior art. The measurement results are shown in Table 2.

[0113] Table 2. Xanthine oxidase inhibition rate

[0114]

[0115] As shown in Table 2, the inhibition rate of the uric acid-lowering polypeptides prepared in Examples 1 to 4 on xanthine oxidase is greater than that of the uric acid-lowering polypeptides prepared in Comparative Examples 1 to 7. The uric acid-lowering polypeptides obtained in the present invention have good xanthine oxidase inhibition effect, which indicates that the uric acid-lowering polypeptides obtained by the process method of the present invention still retain good biological activity.

[0116] Experimental Example 3: Effect of uric acid-lowering polypeptide on the alleviation of hyperuricemia in mice

[0117] After one week of adaptive feeding of mice, 60 mice were gavaged with potassium oxonate (250 mg / kg bw) and adenine (40 mg / kg bw) at fixed time points for ten consecutive days to construct a hyperuric acid model, and mice in the control group were gavaged with an equal amount of normal saline. On the ninth day of modeling, fasting was performed overnight in advance. On the tenth day, blood was collected from the orbits to measure the serum uric acid of mice, and the mice with successful modeling were randomly divided into 12 groups (5 mice in each group), one of which was orally gavaged with deionized water daily as a model group, and the remaining 11 groups were orally gavaged with 40 mg / kg of uric acid-lowering polypeptides prepared in Examples 1 to 4 and Comparative Examples 1 to 7 daily, wherein Comparative Example 7 was a uric acid-lowering polypeptide extracted from a sunflower disk by the prior art. To ensure the stability of the model, all mice need to continue to be gavaged with potassium oxonate and adenine daily. After three weeks of continuous gavage, they were killed, and serum was collected to detect the serum uric acid level and serum xanthine oxidase activity of hyperuricemia mice, and the test results are shown in Table 3.

[0118] Table 3. Serum uric acid levels and serum xanthine oxidase activity in hyperuricemia mice

[0119]

[0120] As shown in Table 3, the serum uric acid index and serum xanthine oxidase activity of the hyperuricemia mice gavaged with the uric acid-lowering polypeptide obtained in Examples 1 to 4 were lower than those of the hyperuricemia mice constructed in the model group, indicating that the process method provided by the present invention can effectively extract the uric acid-lowering polypeptide from the sunflower disk. By comparing the serum uric acid index and serum xanthine oxidase activity of the hyperuricemia mice gavaged with Examples 1 to 4 and Comparative Examples 1 to 7, it can be further illustrated that the process method of the present invention can effectively improve the yield of the uric acid-lowering polypeptide extracted from the sunflower disk, and can effectively protect the biological activity of the uric acid-lowering polypeptide.

[0121] The above-described embodiments provide a detailed description of the technical solutions and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected.

Claims

1. A process for extracting uric acid-lowering polypeptide from sunflower discs, characterized in that: The following steps are involved: The sunflower disk is dried and crushed to obtain sunflower disk powder, the sunflower disk powder is dispersed in a mixed solvent, soaked and ultrasonically treated to obtain defatted sunflower disk powder, the defatted sunflower disk powder and a protein extractant are dispersed in anhydrous ethanol in an inert gas protection environment, stirred for 8 to 12 hours in an environment of 23 to 25° C., and an intermediate product is obtained by magnetic separation, and the intermediate product is hydrolyzed with acid to obtain sunflower disk protein; the sunflower disk protein is enzymatically hydrolyzed once and twice with alkaline protease and papain in sequence, centrifuged and the supernatant is retained, the supernatant is decolorized, and a sunflower disk protein hydrolyzate is obtained by centrifugal filtration and freeze drying; the sunflower disk protein hydrolyzate is separated and purified by column chromatography, and the eluate is collected and freeze-dried to obtain the uric acid-lowering polypeptide; The preparation method of the protein extractant comprises the following steps: Disperse ferric chloride hexahydrate, ferrous chloride tetrahydrate and anhydrous ethanol in deionized water, stir for 10-20 minutes in an inert gas protection environment, adjust the pH to 10-11, then heat to 85-95°C and stir for 2-3 hours. After the reaction is completed, magnetic separation is performed to obtain hydroxyl-modified ferrosoferric oxide. Disperse ferrosoferric oxide and N-oleoylsarcosine in dichloromethane in an inert gas protection environment, add 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride, 4-dimethylaminopyridine and triethylamine are stirred and reacted in an environment of 23-25°C for 24-48 hours, and then N-oleoylsarcosine-modified ferroferric oxide is obtained by magnetic separation; in an inert gas protection environment, N-oleoylsarcosine-modified ferroferric oxide, citral and sodium dodecyl sulfate are dispersed in deionized water, stirred in an environment of 65-75°C for 20-40 minutes, and then benzoyl peroxide is added, the temperature is raised to 80-85°C, and the reaction is stirred for 5-7 hours to obtain the protein extractant.

2. A process for extracting uric acid-lowering polypeptide from a sunflower disk as claimed in claim 1, characterized in that: The weight ratio of the ferric chloride hexahydrate, ferrous chloride tetrahydrate and anhydrous ethanol is 1:0.3-0.5:0.1-0.

3.

3. The process for extracting uric acid-lowering polypeptide from sunflower discs according to claim 1, characterized in that: The weight ratio of the hydroxyl-modified ferrosoferric oxide to N-oleoylsarcosine is 1:0.2-0.

4.

4. The process for extracting uric acid-lowering polypeptide from sunflower discs according to claim 1, characterized in that: The weight ratio of the N-oleoylsarcosine-modified ferroferric oxide, citral and sodium dodecyl sulfate is 81-82:1.4-1.6:25-40.

5. The process for extracting uric acid-lowering polypeptide from sunflower discs according to claim 1, characterized in that: The weight ratio of the defatted sunflower disk powder, the protein extractant and the anhydrous ethanol is 1:25-35:30-50.

6. The process for extracting uric acid-lowering polypeptide from sunflower discs according to claim 1, characterized in that: The conditions of the acid hydrolysis include a hydrolysis pH of 4-5, a hydrolysis temperature of 40-60° C., and a hydrolysis time of 6-8 hours.

7. The process for extracting uric acid-lowering polypeptide from sunflower discs according to claim 1, characterized in that: The conditions of the primary enzymatic hydrolysis include an enzymatic hydrolysis pH of 7-11, an enzymatic hydrolysis temperature of 45-65° C., and an enzymatic hydrolysis time of 1.5-3 h.

8. The process for extracting uric acid-lowering polypeptide from sunflower discs according to claim 1, characterized in that: The conditions of the secondary enzymolysis include an enzymolysis pH of 6.9-7.1, an enzymolysis temperature of 37-45° C., and an enzymolysis time of 2.5-3 h.

9. The process for extracting uric acid-lowering polypeptide from sunflower discs according to claim 1, characterized in that: The decolorization treatment conditions include a decolorization pH of 2-3, a decolorization temperature of 45-55° C., and a decolorization time of 0.5-1.5 h.

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