Swim bladder collagen antioxidant polypeptide as well as screening method and antioxidant performance testing method thereof
By using PepFuncML software for screening and chemical synthesis technology, the antioxidant peptide sequences of fish swim bladder collagen were accurately identified, solving the problems of low screening efficiency and inaccurate testing in existing technologies. This enabled efficient and accurate peptide screening and testing, and the peptides exhibited excellent antioxidant effects.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- GUANGDONG GUANZHAN NUTRITION & HEALTH TECHNOLOGY CO LTD
- Filing Date
- 2026-01-27
- Publication Date
- 2026-05-01
AI Technical Summary
Existing technologies are inefficient and costly in the screening of fish swim bladder peptides, and the screened peptides have unstable activity. Furthermore, the methods for testing antioxidant properties are not precise enough.
PepFuncML software was used for big data analysis and machine learning to screen fish swim bladder collagen antioxidant peptides. Combined with phylogenetic tree construction and chemical synthesis technology, antioxidant peptide sequences were accurately identified, and their performance was tested by DPPH and ABTS methods.
This method improves the efficiency and accuracy of peptide screening, ensuring that the selected peptide sequences have strong and stable antioxidant properties, which is significantly better than traditional methods.
Smart Images
Figure CN121949522A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of biochemistry, specifically to a class of fish swim bladder collagen antioxidant peptides, their screening methods, and antioxidant performance testing methods. Background Technology
[0002] Fish swim bladders, a byproduct of fish production, are rich in collagen and have seen widespread application in the food, health product, and pharmaceutical industries in recent years. The collagen in fish swim bladders and its degradation products—collagen peptides—have attracted increasing attention due to their outstanding biological activity, particularly in anti-oxidation, anti-aging, and skin repair. These collagen peptides possess natural antioxidant properties, capable of scavenging free radicals in the body, slowing down the cellular aging process, and playing a crucial role in skin repair and delaying aging.
[0003] However, despite existing research attempting to discover peptide sequences with antioxidant and anti-aging activities from fish swim bladders, current technologies still face numerous challenges in peptide screening. Traditional screening methods typically rely on extraction or chemical synthesis of peptides followed by experimental verification. These methods suffer from low screening efficiency, high experimental costs, and unstable peptide activity, resulting in poor peptide stability. Furthermore, methods for testing the antioxidant properties of screened peptides are not precise enough. Therefore, how to efficiently and accurately screen peptide sequences with significant anti-aging effects, and how to test the antioxidant properties of screened peptide sequences, remain pressing technical challenges in this field. Summary of the Invention
[0004] To address the aforementioned problems, the main objective of this invention is to provide a class of fish swim bladder collagen antioxidant peptides, a screening method thereof, and a method for testing their antioxidant properties. This screening method for obtaining fish swim bladder collagen antioxidant peptides not only improves screening efficiency but also ensures the antioxidant activity of the screened peptide sequences and provides a method for accurately testing the antioxidant properties of fish swim bladder collagen peptides.
[0005] To achieve the above objectives, this invention provides a class of fish swim bladder collagen antioxidant polypeptides, wherein the polypeptides are natural peptide segments from two type I collagen sequences of fish swim bladder, and the amino acid sequences of the natural peptide segments are any of the following: Polypeptide 1: ARMCRDLRMC; SEQ ID NO. 1; Polypeptide 2: EPCRICV; SEQ ID NO. 2; Polypeptide 3: VWKPEPCRIC; SEQ ID NO. 3; Polypeptide 4: WKPEPCRICV; SEQ ID NO. 4.
[0006] In addition, this invention also provides a method for screening fish swim bladder collagen antioxidant peptides, the operation steps of which include: Step S1, screening of peptide sequences: Step S11, Construction of fish swim bladder collagen short peptide database: Two type I collagen sequences of fish swim bladder are extracted, and then all sequences are deduplicated to obtain a non-redundant type I collagen database of fish swim bladder. Step S12: Use the PepFuncML program to score the antioxidant probability of collagen peptides in the database. The score represents the probability that the sequence has antioxidant properties. Step S13: phylogenetic tree screening of high-scoring sequences: First, the sequences scored in step S12 are sorted; then, sequences are selected for phylogenetic tree construction; finally, multiple polypeptide sequences are selected for chemical synthesis. Step S2, chemical synthesis of peptides, involves synthesizing the target peptides one by one from the peptide sequences obtained in step S13.
[0007] Preferably, the sequence truncation length in step S11 is 2-50 amino acids, and the fish swim bladder non-redundant type I collagen database contains 130,000-140,000 sequences.
[0008] Preferably, in step S13, 200 sequences are selected and a phylogenetic tree is constructed by maximizing the difference. The basis for maximizing the difference is the difference matrix constructed after pairwise sequence alignment.
[0009] Preferably, step S2, during peptide synthesis, also includes confirming the purity and structure of the target peptide.
[0010] Furthermore, this invention also provides a method for testing the antioxidant properties of fish swim bladder collagen antioxidant peptides, specifically including the following steps: (1) Sample preparation: To prepare the test sample solutions, each polypeptide sample was weighed and diluted to distilled water, and then thoroughly mixed to prepare a stock solution. The stock solution was then diluted with distilled water to 10 times and 100 times, respectively, to obtain three different concentrations of test sample solutions. To prepare the glutathione solution, weigh the glutathione sample and dilute it to the volume of distilled water, mix thoroughly to prepare a stock solution; dilute the stock solution 10 times with distilled water to obtain the diluted glutathione test solution. (2) Measurement: Control group: Three test tubes were taken and numbered 1, 2 and 3 respectively. Test tube 1 was filled with DPPH solution and glutathione solution and was used as the experimental group (A). s ); Glutathione solution and anhydrous ethanol solution were added to test tube No. 2 as the control group (A) c ); DPPH solution and distilled water were added to test tube No. 3 as the blank group (A).b After thoroughly mixing in the three test tubes, the mixture was allowed to react at room temperature in the dark, and then its absorbance was measured using a UV spectrophotometer. Sample group: Different concentrations of peptide 1, peptide 2, peptide 3 and peptide 4 solutions obtained from the preparation of the sample solution to be tested were used to replace the glutathione solution. After preparing the sample group solutions according to the preparation steps of the control group, their absorbance values were measured by ultraviolet spectrophotometer. (3) Experimental data processing: Calculate the clearance rate using the following formula: Where P is the clearance rate; A s A represents the absorbance of the mixture of the test solution and DPPH solution; c A is the absorbance of the mixture of the test solution and anhydrous ethanol solution; b The absorbance is the value of the mixture of DPPH solution and sample solvent solution (distilled water).
[0011] Preferably, in the sample preparation step, 1.0 mg of the sample to be tested is weighed and diluted to 1 mL of distilled water to prepare a stock solution with a concentration of 1.0 mg / mL; in the glutathione solution preparation step, 1.0 mg of L-reduced glutathione sample is weighed and diluted to 1 mL of distilled water to prepare a stock solution with a concentration of 1.0 mg / mL, which is then diluted 10 times to obtain a glutathione test solution with a concentration of 0.1 mg / mL.
[0012] Preferably, the mixed solution of the control group and the sample group is reacted at room temperature in the dark for 30 min, and then its absorbance value is measured at a wavelength of 517 nm.
[0013] Furthermore, this invention also provides a method for testing the antioxidant properties of fish swim bladder collagen antioxidant peptides, specifically including the following steps: (1) Sample preparation To prepare the test sample solutions, each polypeptide sample was weighed and diluted to distilled water, and then thoroughly mixed to prepare a stock solution. The stock solution was then diluted with distilled water to 10 times and 100 times, respectively, to obtain three different concentrations of test sample solutions. To prepare the glutathione solution, weigh the glutathione sample and dilute it to the volume of distilled water, mix thoroughly to prepare a stock solution; dilute the stock solution 100 times with distilled water to obtain the diluted glutathione test solution. (2) Measurement: Control group: Two test tubes were taken and numbered 1 and 2 respectively. Test tube 1 contained ABTS solution and glutathione solution, serving as the experimental group (A...). s ); Add ABTS solution and sample solvent solution (distilled water) to test tube No. 2 as the blank group (A bAfter thoroughly mixing the two test tubes, the reaction was carried out at room temperature in the dark, and then the absorbance value was measured using a UV spectrophotometer. Sample group: Different concentrations of peptide 1, peptide 2, peptide 3 and peptide 4 solutions obtained from the preparation of the sample solution to be tested were used to replace the glutathione solution. After preparing the sample group solutions according to the preparation steps of the control group, their absorbance values were measured by ultraviolet spectrophotometer. (3) Experimental data processing: Calculate the clearance rate using the following formula: Where P is the clearance rate; A s A represents the absorbance of the mixture of the test solution and ABTS solution; b The absorbance is the value of the mixture of ABTS solution and sample solvent solution.
[0014] Preferably, in the sample preparation step, 1.0 mg of the sample to be tested is weighed and diluted to 1 mL of distilled water to prepare a stock solution with a concentration of 1.0 mg / mL; in the glutathione solution preparation step, 1.0 mg of L-reduced glutathione sample is weighed and diluted to 1 mL of distilled water to prepare a stock solution with a concentration of 1.0 mg / mL, which is then diluted 100 times to obtain a glutathione test solution with a concentration of 0.01 mg / mL; the mixed solution of the control group and the sample group is reacted at room temperature in the dark for 5 min, and then its absorbance value is measured at a wavelength of 734 nm.
[0015] The beneficial effects of the present invention through the above technical solution include: (1) The present invention provides a class of fish swim bladder collagen antioxidant polypeptides, which contain four different types of polypeptides and have strong and stable antioxidant properties.
[0016] (2) In addition, PepFuncML achieves precise screening of peptide sequences through big data analysis and machine learning technology. The software incorporates advanced bioinformatics algorithms, enabling systematic evaluation of short peptide sequences from fish swim bladder collagen and the identification of peptide sequences with potential antioxidant activity. Compared to traditional manual screening methods, PepFuncML automatically identifies peptide sequences with the strongest antioxidant activity through machine learning models, processing large amounts of data in a short time, greatly improving screening efficiency and accuracy. PepFuncML's core advantage lies in its efficient and precise peptide screening function, avoiding the inefficiencies and errors commonly found in traditional screening methods.
[0017] (3) In addition, during the screening process, the PepFuncML program calculates the antioxidant score of each candidate peptide sequence by analyzing various antioxidant indicators, such as free radical scavenging ability and reducing ability. Combined with deep learning algorithms and bioactivity prediction models, the software can accurately identify the most promising antioxidant peptide sequences and provide important basis for subsequent synthesis and experimental verification. This screening process not only improves the screening speed of antioxidant peptides, but also ensures that the selected peptide sequences have high bioactivity and application potential.
[0018] (4) After screening out polypeptide sequences with significant antioxidant properties, these sequences are chemically synthesized. Chemical synthesis can precisely control the amino acid sequence of the polypeptide, thereby ensuring that the polypeptide has the expected antioxidant activity. After synthesis, the polypeptide will be tested for antioxidant performance by the test method of the present invention to further verify its biological activity. The test results show that these screened polypeptide sequences have excellent antioxidant effects, significantly exceeding the effects of traditional antioxidants. Attached Figure Description
[0019] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.
[0020] Figure 1 This is a schematic diagram of a screening method for a type of fish swim bladder collagen antioxidant polypeptide according to the present invention.
[0021] Figure 2 This is a data graph of type I collagen antioxidant polypeptide DPPH in fish swim bladder of the present invention.
[0022] Figure 3 This is a data graph of ABTS, a type I collagen antioxidant polypeptide in fish swim bladder, according to the present invention. Detailed Implementation
[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.
[0024] First Embodiment like Figure 1 The diagram shown illustrates a method for screening a class of fish swim bladder collagen antioxidant peptides according to the present invention. The specific operation steps are as follows: Step S1, screening of peptide sequences, is divided into the following steps: Step S11, Construction of fish swim bladder collagen short peptide database: Two type I collagen sequences from fish swim bladder are truncated, with a length range of 2 to 50 amino acids. Then, all truncated sequences are deduplicated to obtain a non-redundant type I collagen database from fish swim bladder. This database contains 130,000 to 140,000 sequences, and in this embodiment, it contains 130,665 sequences. Step S12: Use the PepFuncML program to score the antioxidant probability of collagen peptides in the database. Specifically, use the sequences in the fish swim bladder non-redundant type I collagen database from step S11 as input sequences. Use the PepFuncML online AI software to score all sequences in the database. The score represents the probability that the sequence has antioxidant properties. Sort the sequences from high to low according to the scores. Step S13: phylogenetic tree selection is performed on the 200 highest-scoring sequences: First, the sequences with the highest scores in step S12 are sorted; then, the 200 sorted sequences are selected to construct a phylogenetic tree by maximizing differences, based on the difference matrix constructed after pairwise sequence alignment; finally, the 15 polypeptide sequences with the greatest differences are selected for subsequent chemical synthesis. Step S2, chemical synthesis of the peptide: The peptide sequences obtained in step S13 are synthesized one by one into the target peptide using solid-phase synthesis or liquid-phase synthesis. Chemical synthesis methods ensure the high purity and accuracy of the synthesized peptide sequences. After synthesis, the synthesized peptides are quality controlled and their structure verified using mass spectrometry, HPLC (high performance liquid chromatography), and mass spectrometry (MS) to ensure that the synthesized peptides are consistent with the designed sequences and have a purity of over 95%, as shown in the table below. Table 1. Purity of chemically synthesized polypeptide samples from type I collagen fraction in fish swim bladders. The screening method of this invention specifically utilizes PepFuncML software to screen for polypeptide sequences with antioxidant properties. In particular, by screening for short collagen peptides in fish swim bladders, several polypeptide sequences with excellent antioxidant properties are discovered and protected.
[0025] PepFuncML software utilizes big data analytics and machine learning to achieve precise screening of peptide sequences. This software incorporates advanced bioinformatics algorithms to systematically evaluate the sequences of short peptides from fish swim bladder collagen and identify peptide sequences with potential antioxidant activity. Compared to traditional manual screening methods, PepFuncML automatically identifies peptide sequences with the strongest antioxidant activity through machine learning models, processing large amounts of data in a short time, significantly improving screening efficiency and accuracy. PepFuncML's core advantage lies in its efficient and precise peptide screening function, avoiding the inefficiencies and errors commonly found in traditional screening methods.
[0026] During the screening process, PepFuncML analyzes various antioxidant indicators, such as free radical scavenging capacity and reducing capacity, to calculate the antioxidant score of each candidate peptide sequence. Combining deep learning algorithms and bioactivity prediction models, the software can accurately identify the most promising antioxidant peptide sequences, providing crucial information for subsequent synthesis and experimental validation. PepFuncML's screening process not only improves the speed of antioxidant peptide screening but also ensures that the selected peptide sequences possess high bioactivity and application potential.
[0027] The technical solution of this invention innovatively combines the artificial intelligence screening capability of PepFuncML with chemical synthesis technology to achieve efficient screening and preparation of antioxidant peptides. This method not only improves the screening efficiency of antioxidant peptides, but also ensures the antioxidant properties of the selected peptides, thereby providing new and efficient antioxidant components for applications in related fields (such as food, health products, and medicine).
[0028] Furthermore, the screening method described above in this invention breaks through the limitations of traditional methods, significantly improving screening efficiency and accuracy. The polypeptide sequences obtained through the above screening method have strong antioxidant effects. These polypeptides have broad application potential and can be used in the food, health product, and pharmaceutical fields, providing efficient and stable natural antioxidant components while reducing production costs and enhancing the market competitiveness of related industries.
[0029] Second Embodiment Furthermore, this invention also provides a method for testing the antioxidant properties of fish swim bladder collagen antioxidant peptides, the specific details of which are as follows: 1. Testing Principle The antioxidant capacity of peptide sequences was detected using the DPPH method. DPPH is a dark purple prismatic crystal that appears deep purple in anhydrous ethanol solution. DPPH free radicals exhibit a strong absorption peak at a certain wavelength in the visible light region. This method involves the binding of a stable DPPH free radical, provided by DPPH, to an electron provided by the antioxidant peptide, causing the characteristic purple color of the DPPH free radical to disappear, turning it colorless or pale yellow. The absorbance after the reaction was measured using a UV-Vis spectrophotometer, and the free radical scavenging rate P was calculated accordingly.
[0030] 2. The specific steps of the antioxidant performance test are as follows: (1) Sample preparation: Preparation of test sample solutions: Weigh 1.0 mg of each peptide sample and dilute to 1.0 mL of distilled water, mix thoroughly to prepare a stock solution with a concentration of 1.0 mg / mL; then dilute the stock solution with distilled water to 10 times and 100 times respectively to obtain three different concentrations of test sample solutions, namely 1.0 mg / mL, 0.1 mg / mL and 0.01 mg / mL; Preparation of glutathione solution: 1.0 mg of L-reduced glutathione sample was diluted to 1 mL of distilled water and mixed thoroughly to prepare a stock solution with a concentration of 1.0 mg / mL; the stock solution was diluted 10 times with distilled water to obtain a glutathione test solution with a concentration of 0.1 mg / mL after dilution. (2) Measurement: Control group: Take three test tubes, numbered 1, 2 and 3 respectively, and add reagents to each test tube as shown in Table 2 below: Table 2. Types and amounts of reagents added to the control group. Specifically, 3.0 mL of DPPH solution and 1.0 mL of prepared glutathione solution were added to test tube 1 as the experimental group (A). s Add 1.0 mL of the prepared glutathione solution and 3.0 mL of anhydrous ethanol solution to test tube No. 2 as the control group (A). c Add 3.0 mL of DPPH solution and 1.0 mL of distilled water to test tube No. 3 as the blank group (A). b After the three test tubes were thoroughly mixed, they were reacted at room temperature in the dark for 30 minutes. The absorbance was then measured using a UV spectrophotometer at a wavelength of 517 nm. Sample group: Different concentrations of peptide 1, peptide 2, peptide 3, and peptide 4 solutions obtained from the preparation of the test sample solution were used to replace the glutathione solution. The sample group solutions were prepared following the same preparation steps as the control group. Their absorbance values were then measured using a UV spectrophotometer under the same conditions as the control group, as shown in Tables 3 to 6 below. Table 3. Types and amounts of reagents added to the polypeptide 1 sample group Table 4. Types and amounts of reagents added to the polypeptide 2 sample group Table 5. Types and amounts of reagents added to the polypeptide 3 sample group Table 6. Types and amounts of reagents added to peptide 4 sample group (3) Experimental data processing: Calculate the clearance rate using the following formula: Where P is the clearance rate; A s A represents the absorbance of the mixture of the test solution and DPPH solution; c A is the absorbance of the mixture of the test solution and anhydrous ethanol solution; b The absorbance is the value of the mixture of DPPH solution and sample solvent solution (i.e., distilled water).
[0031] Please see Figure 2 The figure shows the DPPH data of type I collagen antioxidant peptides in fish swim bladders. As can be seen from the figure, the free radical scavenging rates of gz-1 (peptide 1), gz-2 (peptide 2), gz-3 (peptide 3) and gz-6 (peptide 4) at concentrations of 1.0 mg / mL and 0.1 mg / mL are higher than those of the control group glutathione (DPPH: 0.1 mg / mL).
[0032] Third Embodiment Furthermore, this invention also provides a method for testing the antioxidant properties of fish swim bladder collagen antioxidant peptides, the details of which are as follows: 1. Testing Principle After oxidation, ABTS generates relatively stable blue-green ABTS+ free radicals, which have a maximum absorption peak at a certain wavelength in the visible light region. When the antioxidant peptides react with the ABTS+ free radicals, they decolorize, and the absorbance at that wavelength decreases. The absorbance after the reaction is measured using a UV-Vis spectrophotometer, and the free radical scavenging rate P is calculated.
[0033] 2. The specific steps of the antioxidant performance testing method in this embodiment are as follows: (1) Sample preparation Preparation of test sample solutions: Weigh 1.0 mg of each peptide sample and dilute to 1 mL of distilled water, mix thoroughly to prepare a stock solution with a concentration of 1.0 mg / mL; then dilute the stock solution with distilled water to 10 times and 100 times respectively to obtain three different concentrations of test sample solutions, namely 1 mg / mL, 0.1 mg / mL and 0.01 mg / mL. Preparation of glutathione solution: Weigh 1.0 mg of L-reduced glutathione sample and dilute to 1 mL of distilled water. Mix thoroughly to prepare a stock solution with a concentration of 1.0 mg / mL. Dilute the stock solution 100 times with distilled water to obtain a glutathione test solution with a concentration of 0.01 mg / mL after dilution. (2) Measurement: Control group: Take two test tubes, numbered 1 and 2 respectively, and add reagents to each test tube as shown in Table 7 below: Table 3. Reagent dosage for control group In test tube 1, 3.6 mL of ABTS solution and 0.4 mL of glutathione solution were added as the experimental group (A). s Add 3.6 mL of ABTS solution and 0.4 mL of sample solvent solution (i.e., distilled water) to test tube No. 2 as the blank group (A). b After the two test tubes were thoroughly mixed, they were reacted at room temperature in the dark for 5 minutes, and then the absorbance was measured by ultraviolet spectrophotometer at a wavelength of 734 nm. Sample groups: Different concentrations of peptide 1, peptide 2, peptide 3, and peptide 4 solutions obtained from the preparation of the test sample solution were used to replace the glutathione solution. The sample group solutions were prepared following the same preparation steps as the control group, and their absorbance values were measured using a UV spectrophotometer under the same conditions as the control group. The details are shown in Tables 8 to 11 below. Table 9. Dosage of Peptide 1 Reagent Table 10. Dosage of Peptide 2 Reagent Added Table 11. Dosage of Peptide 3 Reagent Added Table 12. Dosage of Peptide 4 Reagent Added (3) Experimental data processing: Calculate the clearance rate using the following formula: Where P is the clearance rate; A s A represents the absorbance of the mixture of the test solution and ABTS solution; b The absorbance is the value of the mixture of ABTS solution and sample solvent solution (i.e., distilled water).
[0034] Please see Figure 3 The figure shows the ABTS data of type 1 collagen antioxidant peptides in fish swim bladders. As can be seen from the figure, the free radical scavenging rates of gz-1 (peptide 1), gz-2 (peptide 2), gz-3 (peptide 3) and gz-6 (peptide 4) at concentrations of 1.0 mg / mL and 0.1 mg / mL are higher than those of the control group glutathione (ABTS: 0.01 mg / mL).
[0035] Therefore, the synthesized peptides underwent antioxidant tests using DPPH and ABTS experiments to further verify their biological activity. The test results showed that these screened peptide sequences exhibited excellent antioxidant effects, significantly exceeding the effects of traditional antioxidants. After screening for peptide sequences with significant antioxidant activity, these sequences were chemically synthesized. Chemical synthesis allows for precise control of the peptide's amino acid sequence, thereby ensuring that the peptide possesses the expected antioxidant activity.
[0036] Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.
Claims
1. A type of fish swim bladder collagen antioxidant polypeptide, characterized in that, The polypeptide is a natural peptide segment from two type I collagen sequences of fish swim bladder, and the amino acid sequence of the natural peptide segment is any one of the following: Polypeptide 1: ARMCRDLRMC; SEQ ID NO. 1; Polypeptide 2: EPCRICV; SEQ ID NO. 2; Polypeptide 3: VWKPEPCRIC; SEQ ID NO. 3; Polypeptide 4: WKPEPCRICV; SEQ ID NO.
4.
2. The screening method for a class of fish swim bladder collagen antioxidant peptides according to claim 1, characterized in that, The operating steps include: Step S1, screening of peptide sequences: Step S11, Construction of fish swim bladder collagen short peptide database: Two type I collagen sequences of fish swim bladder are extracted, and then all sequences are deduplicated to obtain a non-redundant type I collagen database of fish swim bladder. Step S12: Use the PepFuncML program to score the antioxidant probability of collagen peptides in the database. The score represents the probability that the sequence has antioxidant properties. Step S13: phylogenetic tree screening of high-scoring sequences: First, the sequences scored in step S12 are sorted; then, sequences are selected for phylogenetic tree construction; finally, polypeptide sequences including SEQ ID NO. 1 to 4 are selected for chemical synthesis. Step S2, chemical synthesis of peptides, involves synthesizing the target peptides one by one from the peptide sequences obtained in step S13.
3. The screening method for a class of fish swim bladder collagen antioxidant peptides according to claim 2, characterized in that, In step S11, the sequence truncation length is 2 to 50 amino acids, and the fish swim bladder non-redundant type I collagen database contains 130,000 to 140,000 sequences.
4. The screening method for a class of fish swim bladder collagen antioxidant peptides according to claim 2, characterized in that, In step S13, 200 sequences are selected and a phylogenetic tree is constructed by maximizing the difference. The basis for maximizing the difference is the difference matrix constructed after pairwise sequence alignment.
5. The screening method for a class of fish swim bladder collagen antioxidant peptides according to claim 2, characterized in that, In step S2, the polypeptide synthesis process also includes confirming the purity and structure of the target polypeptide.
6. The method for testing the antioxidant properties of a class of fish swim bladder collagen antioxidant peptides according to claim 1, characterized in that, Specifically, the steps include the following: (1) Sample preparation: To prepare the test sample solutions, each polypeptide sample was weighed and diluted to distilled water, and then thoroughly mixed to prepare a stock solution. The stock solution was then diluted with distilled water to 10 times and 100 times, respectively, to obtain three different concentrations of test sample solutions. To prepare the glutathione solution, weigh the glutathione sample and dilute it to the volume of distilled water, mix thoroughly to prepare a stock solution; dilute the stock solution 10 times with distilled water to obtain the diluted glutathione test solution. (2) Measurement: Control group: Three test tubes were taken and numbered 1, 2 and 3 respectively. Test tube 1 was filled with DPPH solution and glutathione solution and was used as the experimental group (A). s ); Glutathione solution and anhydrous ethanol solution were added to test tube No. 2 as the control group (A) c ); DPPH solution and distilled water were added to test tube No. 3 as the blank group (A). b After thoroughly mixing in the three test tubes, the mixture was allowed to react at room temperature in the dark, and then its absorbance was measured using a UV spectrophotometer. Sample group: Different concentrations of peptide 1, peptide 2, peptide 3 and peptide 4 solutions obtained from the preparation of the sample solution to be tested were used to replace the glutathione solution. After preparing the sample group solutions according to the preparation steps of the control group, their absorbance values were measured by ultraviolet spectrophotometer. (3) Experimental data processing: Calculate the clearance rate using the following formula: Where P is the clearance rate; A s A represents the absorbance of the mixture of the test solution and DPPH solution; c A is the absorbance of the mixture of the test solution and anhydrous ethanol solution; b The absorbance is the value of the mixture of DPPH solution and sample solvent solution (distilled water).
7. The method for testing the antioxidant properties of a type of fish swim bladder collagen antioxidant polypeptide according to claim 6, characterized in that, In the sample preparation step, 1.0 mg of the sample to be tested is weighed and diluted to 1 mL of distilled water to prepare a stock solution with a concentration of 1.0 mg / mL. In the glutathione solution preparation step, 1.0 mg of L-reduced glutathione sample is weighed and diluted to 1 mL of distilled water to prepare a stock solution with a concentration of 1.0 mg / mL. After diluting 10 times, a glutathione test solution with a concentration of 0.1 mg / mL is obtained.
8. The method for testing the antioxidant properties of a class of fish swim bladder collagen antioxidant peptides according to claim 6, characterized in that, The mixed solution of the control group and the sample group was reacted at room temperature in the dark for 30 min, and then its absorbance value was measured at a wavelength of 517 nm.
9. The method for testing the antioxidant properties of a class of fish swim bladder collagen antioxidant peptides according to claim 1, characterized in that, Specifically, the steps include the following: (1) Sample preparation To prepare the test sample solutions, each polypeptide sample was weighed and diluted to distilled water, and then thoroughly mixed to prepare a stock solution. The stock solution was then diluted with distilled water to 10 times and 100 times, respectively, to obtain three different concentrations of test sample solutions. To prepare the glutathione solution, weigh the glutathione sample and dilute it to the volume of distilled water, mix thoroughly to prepare a stock solution; dilute the stock solution 100 times with distilled water to obtain the diluted glutathione test solution. (2) Measurement: Control group: Two test tubes were taken and numbered 1 and 2 respectively. Test tube 1 contained ABTS solution and glutathione solution, serving as the experimental group (A...). s Add ABTS solution and sample solvent solution (distilled water) to test tube No. 2 as blank group (Ab); after the two test tubes are thoroughly mixed, react at room temperature in the dark, and then measure their absorbance values with a UV spectrophotometer. Sample group: Different concentrations of peptide 1, peptide 2, peptide 3 and peptide 4 solutions obtained from the preparation of the sample solution to be tested were used to replace the glutathione solution. After preparing the sample group solutions according to the preparation steps of the control group, their absorbance values were measured by ultraviolet spectrophotometer. (3) Experimental data processing: Calculate the clearance rate using the following formula: Where P is the clearance rate; A s A represents the absorbance of the mixture of the test solution and ABTS solution; b The absorbance is the value of the mixture of ABTS solution and sample solvent solution.
10. The method for testing the antioxidant properties of a class of fish swim bladder collagen antioxidant peptides according to claim 9, characterized in that, In the sample preparation step, 1.0 mg of the sample to be tested was weighed and diluted to 1 mL of distilled water to prepare a stock solution with a concentration of 1.0 mg / mL. In the glutathione solution preparation step, 1.0 mg of L-reduced glutathione sample was weighed and diluted to 1 mL of distilled water to prepare a stock solution with a concentration of 1.0 mg / mL. After diluting 100 times, a glutathione test solution with a concentration of 0.01 mg / mL was obtained. The mixed solution of the control group and the sample group was reacted at room temperature in the dark for 5 min, and then its absorbance value was measured at a wavelength of 734 nm.