Computer-aided rapid screening method based on peptidomics, collagen antifreeze peptide and its application

Abstract

The present invention discloses a computer-aided rapid screening method based on peptidomics, a collagen antifreeze peptide and its application, which relates to the fields of food biotechnology and bioinformatics. The amino acid sequence of the collagen antifreeze peptide is shown as any one of SEQ ID NO.1-5. The present invention provides a computer-aided rapid screening method for antifreeze peptides based on peptidomics. By performing peptidomics analysis on the cod collagen hydrolysate containing a large number of polypeptides, and according to its physicochemical properties, amino acid composition of the primary structure and molecular docking results, a multi-faceted scoring of the interaction ability between the cod collagen hydrolysate and ice crystals is carried out, so as to rapidly screen out antifreeze peptides with strong interaction ability with ice crystals. The antifreeze peptide provided by the present invention can form multiple hydrogen bonds with ice crystals, and has extremely strong interaction ability with ice crystals, and can be used to prepare antifreeze agents, and then applied to frozen surimi products.

Description

Technical Field

[0001] The present invention relates to the fields of food biotechnology and bioinformatics, and particularly to a computer-aided rapid screening method based on peptidomics, a collagen antifreeze peptide, and its applications. Background Art

[0002] Freezing is a main method for the processing and preservation of aquatic products. However, during frozen storage, protein freeze-denaturation occurs, resulting in deterioration of quality. Generally, adding antifreeze agents is regarded as an effective strategy to improve the water-holding capacity of aquatic products and prevent protein freeze-denaturation. Currently, commonly used antifreeze agents mainly include sugars, proteins, protein hydrolysates, and polyphosphates. However, sugar-based antifreeze agents have limitations such as high calorie content and sweetness; and long-term intake of phosphates will affect the absorption of calcium by the human body. Therefore, the food industry urgently needs new, safe, and efficient antifreeze agents for preventing protein freeze-denaturation. Antifreeze peptides, a type of protein hydrolysates with antifreeze activity, can effectively regulate ice crystal growth and are regarded as high-quality ice crystal regulators. Their raw materials mainly come from food-derived proteins, which have advantages such as rich raw materials, wide sources, and the ability to obtain highly active polypeptide fragments through enzymatic hydrolysis technology, laying a solid foundation for the industrial production and wide application of antifreeze peptides.

[0003] In the processing and preservation of aquatic products, freezing is one of the core methods. However, during frozen storage, protein freeze-denaturation often occurs in aquatic products, leading to a significant decline in quality. To address this challenge, introducing antifreeze agents has become a core strategy to improve the water-holding performance of aquatic products and prevent protein freeze-denaturation. Currently, there are various common antifreeze agents on the market, mainly including sugars, proteins, protein hydrolysates, and polyphosphates. However, the use of sugar-based antifreeze agents is accompanied by problems such as high calorie content and unnecessary sweetness; at the same time, long-term intake of phosphate-based antifreeze agents may also have an adverse impact on human calcium absorption. Given the above limitations, the food industry is committed to developing new, safe, and efficient antifreeze agents for preventing protein freeze-denaturation. Antifreeze peptides, as a type of protein hydrolysates with significant antifreeze activity, stand out among many candidates with their unique ice crystal regulation ability and become a highly regarded ice crystal regulator. Notably, the raw materials of antifreeze peptides mainly come from food-derived proteins, which not only endows them with the significant advantages of rich raw material resources and wide sources, but also provides strong guarantees for food safety and sustainability. In addition, with the continuous progress and innovation of enzymatic hydrolysis technology, we can obtain highly active polypeptide fragments more efficiently, which further consolidates the potential of antifreeze peptides in industrial production and wide application. Looking ahead, antifreeze peptides are expected to become popular in the food industry, bringing a revolutionary change to the field of aquatic product processing and preservation.

[0004] The classical workflow for the identification and characterization of antifreeze peptides includes enzymatic hydrolysis, separation, purification, and qualitative analysis of the purified components, which have been proven to be inefficient and time-consuming. In addition, the antifreeze activity of antifreeze peptides is related to their structure. Although the structural features affecting antifreeze activity have not been clearly defined yet, screening based on the reported characteristics of antifreeze peptides can also yield antifreeze peptides with high antifreeze activity. Therefore, it is of great significance to quickly and accurately identify antifreeze peptides with high antifreeze activity from collagen hydrolysates. However, proteomics can obtain all the identified polypeptide sequences in the hydrolysates through high-resolution mass spectrometry, and a series of database screening can quickly obtain polypeptides that meet the reported characteristics of antifreeze peptides. In addition, molecular docking can be used as an indicator to measure the strength of the interaction between polypeptides and ice crystals. However, the current process for quickly and accurately screening high-activity antifreeze peptides from hydrolysates still needs to be standardized.

[0005] The classical workflow for the identification and characterization of antifreeze peptides encompasses enzymatic hydrolysis, separation, purification, and qualitative analysis of the purified components, which have been demonstrated to be of low efficiency and time-consuming. Additionally, the antifreeze activity of antifreeze peptides is closely associated with their unique structural characteristics. Although there is currently no clear conclusion on which structural features specifically affect antifreeze activity, screening based on the reported characteristics of antifreeze peptides in existing research can still effectively screen out peptides with high antifreeze activity. Therefore, it is of great significance to rapidly and precisely identify antifreeze peptides with high antifreeze activity from collagen hydrolysates for related research and applications. Proteomics technology, leveraging the powerful capabilities of high-resolution mass spectrometry, can comprehensively analyze all polypeptide sequences in the hydrolysates. Subsequently, through a series of sophisticated database screening processes, polypeptides that match the known characteristics of antifreeze peptides can be quickly identified. Furthermore, molecular docking technology can serve as a powerful tool for evaluating the strength of the interaction between polypeptides and ice crystals. However, there is an urgent need for standardization and regularization in the current process of quickly and accurately screening high-activity antifreeze peptides from hydrolysates.

[0006] The present invention intends to construct a computer-aided rapid screening method for antifreeze peptides based on proteomics, which aims to accurately screen out antifreeze peptides with significant interaction ability with ice crystals from cod collagen hydrolysates, thereby providing strong technical support for the research and development of new antifreeze agents. Summary of the Invention

[0007] The objective of the present invention is to provide a computer-aided rapid screening method based on proteomics, collagen antifreeze peptides, and their applications to solve the problems existing in the above-mentioned prior art. Five antifreeze peptides have been screened from the collagen hydrolysates of cod, which can form multiple hydrogen bonds with ice crystals, have extremely strong interaction ability with ice crystals, the thermal hysteresis activity values are all greater than 1.0 °C, and the residual enzyme activity of catalase is above 50% after adding these antifreeze peptides.

[0008] To achieve the above object, the present invention provides the following solutions:

[0009] The present invention provides a collagen antifreeze peptide AFP-1, and its amino acid sequence is shown as SEQ ID NO.1.

[0010] The present invention also provides a collagen antifreeze peptide AFP-2, and its amino acid sequence is shown as SEQ ID NO.2.

[0011] The present invention also provides a collagen antifreeze peptide AFP-3, and its amino acid sequence is shown as SEQ ID NO.3.

[0012] The present invention also provides a collagen antifreeze peptide AFP-4, and its amino acid sequence is shown as SEQ ID NO.4.

[0013] The present invention also provides a collagen antifreeze peptide AFP-5, and its amino acid sequence is shown as SEQ ID NO.5.

[0014] The present invention also provides the use of the above-mentioned collagen antifreeze peptide AFP-1, collagen antifreeze peptide AFP-2, collagen antifreeze peptide AFP-3, collagen antifreeze peptide AFP-4 or collagen antifreeze peptide AFP-5 in the preparation of antifreeze agents.

[0015] The present invention also provides an antifreeze agent, and its active ingredients include at least one of collagen antifreeze peptide AFP-1, collagen antifreeze peptide AFP-2, collagen antifreeze peptide AFP-3, collagen antifreeze peptide AFP-4 or collagen antifreeze peptide AFP-5.

[0016] The present invention also provides the use of the above-mentioned collagen antifreeze peptide AFP-1, collagen antifreeze peptide AFP-2, collagen antifreeze peptide AFP-3, collagen antifreeze peptide AFP-4 and / or collagen antifreeze peptide AFP-5 in the preparation of frozen surimi products.

[0017] The present invention also provides the use of the above-mentioned antifreeze agent in the preparation of frozen surimi products.

[0018] The present invention also provides a computer-aided rapid screening method for antifreeze peptides based on peptidomics, comprising the following steps:

[0019] The polypeptide sequence is obtained by peptidomic analysis of the collagen hydrolysate;

[0020] The physicochemical properties of the polypeptide are predicted by inputting the polypeptide sequence into the Expasy server to obtain the instability index and the total average hydrophilicity of the polypeptide;

[0021] Each polypeptide is scored according to the peptide chain length, the instability index, the total average hydrophilicity, whether it contains hydrophilic amino acids, whether it contains hydrophobic amino acids, whether it contains acidic amino acids, and whether it contains basic amino acids, to obtain a physicochemical property score;

[0022] According to the score of each amino acid and the amino acid sequence of the polypeptide, the amino acid composition of each polypeptide is scored to obtain an amino acid composition score;

[0023] Statistical analysis is performed on the molecular docking results of the interaction between each polypeptide and ice crystals, and a score is given to obtain a molecular docking score;

[0024] The physicochemical property score, the amino acid composition score, and the molecular docking score are added together to obtain a total score;

[0025] Antifreeze peptides with strong interaction ability with ice crystals are screened according to the total score of each polypeptide.

[0026] The present invention discloses the following technical effects:

[0027] The present invention provides a computer-aided rapid screening method for antifreeze peptides based on peptidomics. By performing peptidomics analysis on the cod collagen hydrolysate containing a large number of polypeptides, and according to their physicochemical properties, the amino acid composition of the primary structure, and the molecular docking results, a multi-faceted score is given to the interaction ability between the polypeptides and ice crystals, so as to rapidly screen out antifreeze peptides with strong interaction ability with ice crystals. This screening method has the characteristics of simple operation, fast screening speed, and high accuracy, and can become a reference for the standardized screening of antifreeze peptides.

[0028] The present invention has screened out 5 antifreeze peptides from the collagen hydrolysate of cod, which can form multiple hydrogen bonds with ice crystals, have extremely strong interaction ability with ice crystals, the thermal hysteresis activity values are all greater than 1.0 °C, and the residual enzyme activity of catalase is above 50% after adding these antifreeze peptides.

[0029] The antifreeze peptides provided by the present invention can be used to prepare antifreeze agents, and then applied to frozen surimi products. Description of the Drawings

[0030] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required to be used in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0031] Figure 1 It is a statistical chart of the detection results of the cryoprotective effect of cod collagen hydrolysate, P1 component, and P2 component on catalase;

[0032] Figure 2 It is the first - level mass spectrum of the polypeptide sourced from cod fish collagen;

[0033] Figure 3 It is the molecular docking diagram of the polypeptide KDARTSDW and ice crystals; among them, A is the 3D schematic diagram of the interaction between KDARTSDW and ice crystals; B is the 2D schematic diagram of the interaction between KDARTSDW and ice crystals;

[0034] Figure 4 It is the molecular docking diagram of the polypeptide LGDGGFQR and ice crystals; among them, A is the 3D schematic diagram of the interaction between LGDGGFQR and ice crystals; B is the 2D schematic diagram of the interaction between LGDGGFQR and ice crystals;

[0035] Figure 5 It is the molecular docking diagram of the polypeptide DKQNTMGD and ice crystals; among them, A is the 3D schematic diagram of the interaction between DKQNTMGD and ice crystals; B is the 2D schematic diagram of the interaction between DKQNTMGD and ice crystals;

[0036] Figure 6 It is the molecular docking diagram of the polypeptide DEVQKAVA and ice crystals; among them, A is the 3D schematic diagram of the interaction between DEVQKAVA and ice crystals; B is the 2D schematic diagram of the interaction between DEVQKAVA and ice crystals;

[0037] Figure 7 It is the molecular docking diagram of the polypeptide DGAPGKDGIR and ice crystals; among them, A is the 3D schematic diagram of the interaction between DGAPGKDGIR and ice crystals; B is the 2D schematic diagram of the interaction between DGAPGKDGIR and ice crystals;

[0038] Figure 8 It is the statistical chart of the cryoprotective effect of the antifreeze peptide on catalase and the detection results of thermal hysteresis activity. Detailed implementation manners

[0039] Now, various exemplary implementation manners of the present invention will be described in detail. This detailed description should not be regarded as a limitation of the present invention, but should be understood as a more detailed description of certain aspects, characteristics, and implementation schemes of the present invention.

[0040] It should be understood that the terms described in the present invention are only for describing specific implementation manners and are not used to limit the present invention. Additionally, for the numerical ranges in the present invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Each intermediate value within any stated value or stated range, as well as each smaller range between any other stated value or intermediate value within the stated range, is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded from the range.

[0041] Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. Although this invention only describes preferred methods and materials, any methods and materials similar or equivalent to those described herein can also be used in the practice or testing of this invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials related to the said documents. In case of conflict with any incorporated document, the content of this specification shall prevail.

[0042] Without departing from the scope or spirit of this invention, various improvements and changes can be made to the specific embodiments of the description of this invention, which are obvious to those skilled in the art. Other embodiments obtained from the description of this invention are obvious to those skilled in the art. The description and examples of this invention are merely exemplary.

[0043] Regarding the use of "comprising", "including", "having", "containing", etc. herein, they are all open-ended terms, meaning including but not limited to.

[0044] The method for verifying the antifreeze activity of the polypeptide adopted in this invention is as follows:

[0045] 1. Detection method for the cryoprotective effect of catalase

[0046] Dilute catalase by a certain multiple and prepare a solution with a polypeptide concentration of 1 - 5 mg / mL. Add catalase to the polypeptide solution, and do not add the polypeptide solution to the blank group. Measure the initial activity of catalase before freezing at 240 nm. Put the catalase solution into a -20°C refrigerator and freeze it for 12 h, quickly thaw it and then put it back into the -20°C refrigerator for freezing for 3 h. Repeat the freeze-thaw cycle three times and measure the activity of catalase. By measuring the residual activity of catalase in (1) and (2), its antifreeze activity can be represented.

[0047]

[0048] 2. Detection method for thermal hysteresis activity

[0049] Use differential scanning calorimetry to analyze the thermal hysteresis activity of the antifreeze peptide of cod collagen obtained by screening. Dissolve the polypeptide in pure water to prepare a solution with a concentration of 5 - 20 mg / mL. Take bovine serum albumin as a comparison, pipette the sample into a crucible with a pipette gun, measure the melting point and crystallization point of the sample, record the initial crystallization temperature, and calculate the thermal hysteresis activity according to formula (3).

[0050] Thermal hysteresis activity = T h - T0 (3)

[0051] In the formula: T hT is the temperature, (°C); T0 is the initial crystallization temperature (°C).

[0052] Example 1

[0053] The 200 - 3000 Da cod fish collagen hydrolysate used in this example was purchased from Zhengzhou Jiangda Biotechnology Co., Ltd.

[0054] Preparation method of the collagen antifreeze component:

[0055] S1. Using the 200 - 3000 Da cod fish collagen hydrolysate as the raw material, prepare it into a 10 mg / mL solution.

[0056] S2. Configure the mobile phase, Phase A: 0.01 mol Tris - HCl pH = 8.0; Phase B: 1.0 mol NaCl, 0.01 mol Tris - HCl pH = 8.0.

[0057] S3. Use the ion exchange method to separate and purify the 10 mg / mL solution obtained in step S1. The Capto Q anion column separates the cod fish collagen hydrolysate under the conditions of a detection wavelength of 220 nm and a flow rate of 5 mL / min.

[0058] S4. Name the two separated component solutions as Component P1 and Component P2 respectively. Concentrate them separately using a rotary evaporator, and then place them in a vacuum freeze dryer for freeze - drying to obtain the ion exchange method purified product powder, and store it in a 4°C refrigerator.

[0059] Measure the cryoprotective effects of the 200 - 3000 Da cod fish collagen hydrolysate, Component P1, and Component P2 on catalase. The results are shown in Figure 1 . The results show that Component P1 has a stronger cryoprotective effect on catalase.

[0060] Example 2

[0061] Identify polypeptides by mass spectrometry. The method is as follows:

[0062] Polypeptide sequence identification of Component P1 by mass spectrometry

[0063] Liquid chromatography conditions: Chromatographic column: Thermo - scientific EASY column C18 (3μm i.d.×75μm, Thermo - Fisher scientific, USA); Mobile phase A: 0.1% formic acid; Mobile phase B: 0.1% formic acid, 84% acetonitrile; Flow rate: 250 nL / min; 0 - 110 min, linear gradient of liquid B from 0 - 35%; 110 - 118 min, linear gradient of liquid B from 35 - 100%; 118 - 120 min, liquid B remains at 100%.

[0064] Mass spectrometry conditions: For the first-level mass spectrometry, the resolution is 70000, the AGC target is 3e6, the maximum limit is 10 ms, and the scanning range is 300 - 1800 m / z; for the second-level mass spectrometry, the resolution is 17500, the normalized collision energy is 30 eV, and the bottom fill rate is 0.1%.

[0065] The original mass spectrometry identification file was used to search the Uniprot database with Maxquant software to obtain the polypeptide sequences belonging to the collagen source, and the first-level mass spectrometry map was obtained ( Figure 2 ).

[0066] Example 3

[0067] 1. Screening of antifreeze peptides

[0068] 1.1 Preliminary screening

[0069] According to the ion scores of the polypeptides in the mass spectrometry data of the peptidomics analysis in Example 2, all the identified polypeptides were ranked. The higher the ion score, the higher the confidence and accuracy of the identification of the polypeptide in the mass spectrometry. The top 100 polypeptides with the highest ion scores were selected for the next step of screening.

[0070] 1.2 Score according to the physicochemical properties of the polypeptide, and the steps are as follows:

[0071] S1. Use a nano-liquid chromatography - quadrupole orbitrap mass spectrometer to identify the amino acid sequence, peptide chain length, amino acid composition and other physicochemical properties of the polypeptides contained in the P1 component in Example 1; and rank the polypeptides according to the ion scores, and select the top 100 polypeptides with the highest ion scores for the next step of screening;

[0072] S2. Input the polypeptide sequences identified in S1 into the Uniport database to analyze the polypeptide sources, and screen out the polypeptide sequences from the collagen source;

[0073] S3. Predict the instability index and the total average hydrophilicity (GRAVY) of the polypeptide sequences identified in S2 through the Expasy server (https: / / web.expasy.org / protparam / );

[0074] S4. Score each polypeptide according to its physicochemical properties, including the following three indicators: polypeptides with a peptide chain length of 7 - 14 amino acids, containing hydrophilic amino acids, hydrophobic amino acids and an instability index < 40, and each of the above three indicators is 5 points;

[0075] S5. Score according to the amino acid composition of the polypeptide, including the following four indicators: containing hydrophilic amino acids, hydrophobic amino acids, and each of the above two indicators is 5 points; and polypeptides containing basic amino acids and acidic amino acids, and each of the above two indicators is 10 points;

[0076] S6. Score each identified polypeptide according to the criteria in S3 and S4. Among them, the total score for the physicochemical property part is 50 points. The scores of each polypeptide are statistically sorted to obtain Table 1.

[0077] Table 1 Polypeptide Physicochemical Property Scoring Table

[0078]

[0079]

[0080]

[0081] 1.3 Score according to the amino acid composition of the polypeptide. The steps are as follows:

[0082] S1. Score each amino acid according to the C=O, OH, and NH functional groups contained in the amino acid. Score each amino acid according to the following criteria. The number of O atoms, the number of C=O functional groups, the number of OH functional groups, and the number of NH functional groups in the amino acid are all 1 point per unit;

[0083] S2. Calculate the score of each amino acid according to the criteria given in S1 to obtain Table 2;

[0084] S3. Calculate the amino acid composition score of each polypeptide according to the polypeptide amino sequence in Table 1 and the amino acid scores in Table 2 to obtain Table 3.

[0085] Table 2 Amino Acid Scoring Table According to Its Contained Functional Groups

[0086]

[0087] Table 3 Polypeptide Sequence Amino Acid Composition Scoring Table

[0088]

[0089]

[0090]

[0091] 1.4 Score according to the polypeptide molecular docking results. The steps are as follows:

[0092] S1. Use AlphaFold2 to construct the secondary structure model of the polypeptide sequences in Table 1. Construct 5 models for each polypeptide, and select the polypeptide model with the highest PLDDT value as the secondary structure of the polypeptide;

[0093] S2. Download the cubic ice crystal structure from GenIce 1.0.10 for subsequent molecular docking with the polypeptide;

[0094] S3. Use the molecular docking software Autodock 1.5.6 to perform molecular docking between the polypeptide and ice crystal to obtain the optimal conformation;

[0095] S4. Use Discovery studio 19.1.0 to visualize the optimal conformation of the molecular docking between the polypeptide obtained in S3 and the ice crystal molecule;

[0096] S5. After visualizing the docking results in S4, count the number of hydrogen bonds formed by the interaction between the polypeptide and the ice crystal, and the interaction forces formed between amino acid residues, such as salt bridges, electrostatic interactions, and alkyl side chains;

[0097] S6. Score the statistical results in S5 according to the following criteria. Hydrogen bonds formed by the oxygen atom of the amino acid and the hydrogen atom of the water molecule are 1 point per bond, carbon-hydrogen bonds are 2 points per bond, hydrogen bonds formed by the amino group of the amino acid and the oxygen atom of the water molecule are 5 points per bond, hydrogen bonds formed by the hydrogen atom of the amino acid and the oxygen atom of the water molecule are 1 point per bond, salt bridges are 5 points per bond, electrostatic interactions are 5 points per bond, and alkyl side chains are 2 points per bond. Among them, only when the docking affinity is less than -5 kcal / mol is it considered that the polypeptide can stably bind to the ice crystal.

[0098] S7. Sum up the scores in S6, calculate the score of the molecular docking result between the polypeptide and the ice crystal molecule, and obtain Table 4.

[0099] Schematic diagrams of the molecular docking of polypeptides KDARTSDW, LGDGGFQR, DKQNTMGD, DEVQKAVA, and DGAPGKDGIR with ice crystals are shown respectively in Figures 3 - 7 .

[0100] Table 4 Scoring Table for Molecular Docking Results

[0101]

[0102]

[0103]

[0104] 1.5 Screening of Antifreeze Peptides According to Calculated Scores

[0105] Calculate the total scores of the physicochemical properties, amino acids composing the polypeptide, and molecular docking results of each polypeptide respectively, and then perform the final screening according to the scores of each peptide. The higher the score, the higher the confidence that the polypeptide is an antifreeze peptide and the stronger its ability to interact with ice crystals. Finally, collagen antifreeze peptides with strong interaction ability with ice crystals are screened according to the scores of each peptide. The specific steps are as follows:

[0106] S1. Sum the scores of each polypeptide in Examples 1.2, 1.3, and 1.4, that is, sum the scores of each polypeptide in Tables 1, 3, and 4.

[0107] S2. Statistically analyze the scores obtained by summing each polypeptide in S1. Evaluate the ability of the polypeptide to interact with ice crystals from three aspects: physical and chemical properties, amino acid composition, and molecular docking results, and obtain Table 5.

[0108] S3. Select the top 5 polypeptides with the highest scores from Table 5, KDARTSDW (named AFP-1, SEQ ID NO.1), LGDGGFQR (named AFP-2, SEQ ID NO.2), DKQNTMGD (named AFP-3, SEQ ID NO.3), DEVQKAVA (named AFP-4, SEQ ID NO.4), DGAPGKDGIR (named AFP-5, SEQ ID NO.5) and prepare to verify their antifreeze activities in the next step.

[0109] Table 5 Total scores of physical and chemical properties of polypeptides, amino acids constituting the polypeptides, and molecular docking results

[0110]

[0111]

[0112]

[0113] 2. Verification of antifreeze activities of antifreeze peptides

[0114] Prepare solutions of the screened antifreeze peptides at 10 mg / mL and verify their antifreeze activities respectively (using bovine serum albumin and the catalase dilution without peptide mixture as the control groups), including detecting their cryoprotective effects on catalase and thermal hysteresis activities. The results are shown in Figure 8 . The results show that the screened antifreeze peptides KDARTSDW, LGDGGFQR, DKQNTMGD, DEVQKAVA, and DGAPGKDGIR of the present invention all have strong cryoprotective effects on catalase and thermal hysteresis activities.

[0115] The above-described embodiments are only descriptions of the preferred modes of the present invention and do not limit the scope of the present invention. Without departing from the design spirit of the present invention, various deformations and improvements made by those of ordinary skill in the art to the technical solutions of the present invention shall fall within the protection scope determined by the claims of the present invention.

Claims

1. A collagen antifreeze peptide AFP-1, characterized in that: The amino acid sequence is shown in SEQ ID NO.

1.

2. Use of the collagen antifreeze peptide AFP-1 as claimed in claim 1 in the preparation of antifreeze agents.

3. An antifreeze agent, characterized in that: The active ingredient comprises the collagen antifreeze peptide AFP-1 as claimed in claim 1.

4. Use of the collagen antifreeze peptide AFP-1 as claimed in claim 1 in the preparation of frozen surimi products.

5. Use of the antifreeze agent as claimed in claim 3 in the preparation of frozen surimi products.

Images