Polypeptide NPAAKMSPKPATP and application thereof in biological preservative

Abstract

The invention discloses a polypeptide NPAAKMSPKPATP and application thereof in a biological fresh-keeping agent, and the method comprises the following steps: S1, preparation of a Paenibacillus provens PP-2 metabolite: solidifying Paenibacillus provens PP-2 in an LB solid culture medium, carrying out inoculation streak, placing the Paenibacillus provens PP-2 in a constant temperature incubator, carrying out inverted culture for 48 h, picking single colonies, inoculating the single colonies into an LB liquid culture medium, and carrying out freeze drying to obtain the Paenibacillus provens PP-2 metabolite. And then inoculating into an LB liquid culture medium according to the addition amount of 1%, and culturing for 7 days. Then centrifuging for 10 minutes at the speed of 8000 r / min and the temperature of 4 DEG C, discarding the precipitate, remaining the supernate, and filtering and sterilizing by using a 0.22 mu m filter membrane, so as to obtain the paenibacillus provenensis PP-2 metabolite; p. The biological fresh-keeping agent is prepared by adopting the polypeptide prepared from the paenibacillus provenensis PP-2 metabolite and matching with the procyanidine and the agaro-oligosaccharide, has a good fresh-keeping effect and a good antibacterial effect, and can overcome the defects of a traditional fresh-keeping method.

Description

Technical Field

[0001] The present invention relates to the technical field of the preparation of biological preservatives, and particularly to a polypeptide NPAAKMSPKPATP and its application in biological preservatives. Background Art

[0002] Due to the high water content, fresh aquatic products are usually susceptible to the influence of endogenous enzymes and microorganisms under the storage condition of 4°C, resulting in spoilage and affecting the edible value. The disadvantages of traditional preservation methods are obvious when dealing with this problem. For example, chemical preservatives may leave harmful substances in food, thus bringing potential food safety hazards; physical preservation methods have the problem of high cost, and there are also certain limitations in the preservation effect, making it difficult to meet the requirements of long-term and efficient preservation; while biological preservatives, with their natural, green and safe characteristics, have gradually become the development trend in the current preservation field.

[0003] At present, there is no systematic report on the metabolites of Paenibacillus provencensis PP-2 in the preservation of aquatic products, and there is a large research gap and exploration space. Conducting in-depth research on the metabolites of Paenibacillus provencensis PP-2 opens up a broad prospect for the development of new and efficient biological preservatives, and has extremely high research value and application potential. Biological preservatives, with their natural, green and safe characteristics, have gradually become a research hotspot in the field of aquatic product preservation. As a potential source of natural polypeptides, the metabolites of Paenibacillus provencensis PP-2 are expected to overcome the deficiencies of traditional preservation methods in the biological preservatives developed in combination with proanthocyanidins and agar oligosaccharides, providing a new direction for the innovation of aquatic product preservation technology.

[0004] In addition, proanthocyanidins are a powerful natural antioxidant that can effectively scavenge free radicals and slow down the oxidation process, which helps to extend the shelf life of fish, maintain its color, flavor and nutritional components. As a natural water-soluble polysaccharide, agar oligosaccharides can form gels, enhance the water-holding capacity of fish, reduce water loss, and thus prevent fish from drying and texture deterioration. Proanthocyanidins also have certain antibacterial properties, which can inhibit the growth of microorganisms on the surface and inside of fish, helping to reduce the risk of food spoilage, and the viscosity of agar oligosaccharides can form a protective film to further block the invasion of microorganisms.

[0005] The present invention provides a polypeptide NPAAKMSPKPATP derived from the metabolites of Paenibacillus provencensis PP-2 and its application in the preparation of biological preservatives for the above technical problems. Summary of the Invention

[0006] The present invention provides a polypeptide NPAAKMSPKPATP and its application in biological preservatives, solving the problems in the background art.

[0007] To achieve the above object, the present invention adopts the following technical solutions: A polypeptide NPAAKMSPKPATP, comprising the following steps: S1. Preparation of metabolites of Paenibacillus provencensis PP-2: Paenibacillus provencensis PP-2 was inoculated and streaked after the LB solid medium solidified, and then placed in an incubator at a constant temperature for inverted culture for 48 h. Single colonies were picked and inoculated into the LB liquid medium, and cultured in a sterile shaker for 24 h. Then, it was inoculated into the LB liquid medium at an addition amount of 1% and cultured for 7 d. Subsequently, centrifuged at 8000 r / min and 4 °C for 10 min, the precipitate was discarded and the supernatant was retained, and filtered and sterilized with a 0.22 μm filter membrane to obtain the metabolites of Paenibacillus provencensis PP-2; S2. Isolation and purification of the polypeptide NPAAKMSPKPATP from the metabolites in step S1: Gel column chromatography was used to further screen the antibacterial components of the metabolites of Paenibacillus provencensis PP-2 to obtain peptide segments, and then the peptide sequences were identified and analyzed, and the polypeptide NPAAKMSPKPATP was synthesized after analysis.

[0008] Further, in step S2, the LC-MS method was used to identify the peptide sequences, and the mobile phase A of the peptide sequences was 0.1% formic acid and 2% acetonitrile; the mobile phase B was 0.1% formic acid and 80% acetonitrile.

[0009] Further, in step S2, the de novo method was used to analyze the peptide sequences, and mass spectrometry analysis was performed using a Q-Exactive HF-X mass spectrometer in the data-dependent acquisition mode.

[0010] Further, in step S2, the polypeptide NPAAKMSPKPATP was synthesized by the Fmoc solid-phase synthesis method.

[0011] Another object of the present invention is to provide an application of the polypeptide NPAAKMSPKPATP in a biological preservative.

[0012] Further, a preparation method of a biological preservative containing the polypeptide NPAAKMSPKPATP: The polypeptide NPAAKMSPKPATP powder was dissolved in sterile distilled water, and proanthocyanidins and agar oligosaccharides were added and mixed evenly to obtain a composite biological preservative.

[0013] Further, the concentration of the polypeptide NPAAKMSPKPATP powder after being dissolved in sterile distilled water is 180 mg / mL.

[0014] Further, the mass concentration of the proanthocyanidins is 0.2% w / v.

[0015] Furthermore, the mass concentration of the agar oligosaccharide is 0.5% w / v.

[0016] In summary, due to the adoption of the above technical solutions, the beneficial effects of the present invention are as follows: The present invention uses the metabolites of Paenibacillus provencensis PP-2 to prepare polypeptides, and combines them with procyanidins and agar oligosaccharides to make a biological preservative. This biological preservative has good preservation and antibacterial effects and can overcome the deficiencies of traditional preservation methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is the mass spectrometry diagram of polypeptide NPAAKMSPKPATP; Figure 2 It is the curve diagram of bacterial survival rate under different treatment conditions; Figure 3 It is the transmission electron microscopy diagram of Stenotrophomonas acidaminiphila under different treatment conditions and different action conditions; Figure 4 It is the diagram of the influence of different conditions on the cell activity of Stenotrophomonas acidaminiphila; Figure 5 It is the diagram of the change of SDS-PAGE electrophoresis results of myofibrillar protein over time; Figure 6 It is the diagram of the change of the microstructure of myofibrillar protein over time; Figure 7 It is the diagram of the influence of the composite biological preservative on the microstructure of protein gel. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0018] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.

[0019] The preparation process of a polypeptide NPAAKMSPKPATP is as follows: Step 1, preparation of metabolites of Paenibacillus provencensis PP-2 and separation and purification of polypeptide NPAAKMSPKPATP: Paenibacillus provencensis PP-2 was isolated from sturgeon caviar prepared by Xinglong Technology Co., Ltd. in Quzhou City, Zhejiang Province, and was deposited in the China Center for Type Culture Collection with the deposit number CCTCC NO: M 20211109. The preservation information and specific details of this strain are recorded in the Chinese invention patent CN 114134085A. CN 114134085 A discloses its application in inhibiting the formation of nitrosamines in food. Paenibacillus provencensis PP-2 was inoculated and streaked after the LB solid medium solidified, and then placed in an incubator at a constant temperature for inverted culture for 48 h. Single colonies were picked and inoculated into LB liquid medium, cultured in a sterile shaker for 24 h, and then inoculated into LB liquid medium at an addition amount of 1% and cultured for 7 d. Subsequently, centrifuged at 8000 r / min at 4 °C for 10 min, the precipitate was discarded and the supernatant was retained, and filtered through a 0.22 μm filter membrane to remove bacteria to obtain the metabolites of Paenibacillus provencensis PP-2. Gel column chromatography was used to further screen the antibacterial components of the metabolites of Paenibacillus provencensis PP-2 to obtain the peptide segment with the best antibacterial effect. The peptide sequence was identified by LC-MS method. Mobile phase A was 0.1% formic acid and 2% acetonitrile; mobile phase B was 0.1% formic acid and 80% acetonitrile; the peptide sequence was analyzed by the de novo method. Mass spectrometry analysis was performed using a Q-Exactive HF-X mass spectrometer in the data-dependent acquisition mode; after separation and identification, the content of NPAAKMSPKPATP (Asp-Pro-Ala-Ala-Lys-Met-Ser-Pro-Lys-Pro-Ala-Thr-Pro) was the highest, indicating that this peptide segment was closely related to the antibacterial activity of the metabolites of Paenibacillus provencensis PP-2. The polypeptide was synthesized by the Fmoc solid-phase synthesis method.

[0020] The application of a polypeptide NPAAKMSPKPATP in a biological preservative was studied as follows: Using Stenotrophomonas acidaminiphila as the experimental strain, the antibacterial activity of the metabolites of PP-2 was determined by the microdilution method. Nisin and the polypeptide NPAAKMSPKPATP were respectively added to the activated fermentation broth to make the metabolite concentration 50 mg / mL, 60 mg / mL, 70 mg / mL, 80 mg / mL, 90 mg / mL, 100 mg / mL, 150 mg / mL, 180 mg / mL, 200 mg / mL, 250 mg / mL. After mixing, 200 μL was taken and added to a 96-well plate. The medium containing the fermentation broth of Stenotrophomonas acidaminiphila at the same concentration was used as the blank control group. Incubated in a sterile shaker at 30 °C for 12 h, and OD was measured. 600Size.

[0021] The antibacterial activities of different treatment conditions against Stenotrophomonas acidaminiphila. As the concentration of the polypeptide NPAAKMSPKPATP increased continuously, the antibacterial rate showed a trend of first increasing and then stabilizing. When the concentration of the polypeptide NPAAKMSPKPATP was 180 mg / mL, the antibacterial rate against Stenotrophomonas acidaminiphila reached 73.11 ± 1.77%. When the concentration was greater than 180 mg / mL, the antibacterial rate did not change significantly. Therefore, the minimum inhibitory concentration of the polypeptide NPAAKMSPKPATP against Stenotrophomonas acidaminiphila was determined to be 180 mg / mL. The minimum inhibitory concentration of the control group Nisin was 100 mg / mL.

[0022] As Figure 2 shown, the morphological changes of Stenotrophomonas acidaminiphila cells were observed by transmission electron microscopy. Samples were taken at 6 h of culture, centrifuged at 8000 r / min and 4 °C for 10 min, and then the supernatant was discarded and the precipitate was retained. Sterile PBS solution was added to the precipitate, centrifuged, and the supernatant was discarded and the precipitate was retained. This washing process was repeated three times. 2.5% (v:v) glutaraldehyde fixative was added to the cell pellet, and the cells were fixed overnight at 4 °C. 10 μL of the bacterial solution was dropped on a copper mesh. After it dried, it was washed with sterile PBS solution and dried again. Finally, the treated sample was placed under a transmission electron microscope to observe the morphological changes of S-1 cells.

[0023] Based on transmission electron microscopy technology, the morphological changes of the cells of Stenotrophomonas acidaminiphila treated with the blank control group, the Nisin group, and the polypeptide NPAAKMSPKPATP group were observed as shown in the figure. The cells in the blank control group were plump and the cell morphology was intact; the cell morphology in the Nisin group was relatively intact with no obvious changes. After treatment with the polypeptide NPAAKMSPKPATP group, the cell membrane was dissolved, the bacteria were severely damaged, cavities appeared in the cells, the contents leaked, and the normal growth and metabolism of the cells could not be maintained, resulting in cell death. This result confirmed that the polypeptide NPAAKMSPKPATP could achieve antibacterial effects by destroying the integrity of the cell membrane.

[0024] As Figure 3As shown in the figure, the lethal effect of polypeptide NPAAKMSPKPATP on Stenotrophomonas acidaminiphila was detected by propidium iodide (PI) single staining method. The samples were taken out when cultured for 6 h, centrifuged at 8000 r / min at 4°C for 10 min, the supernatant was discarded and the precipitate was left. The precipitate was washed with sterile PBS solution and repeated three times, and finally resuspended in sterile PBS solution. The PI cell viability and cytotoxicity detection kit was used for the experiment. 100 μL of bacterial suspension and 30 μL of PI staining solution were added to a sterile centrifuge tube, reacted in a dark incubator for 30 min, centrifuged at 5000 r / min at 4°C for 10 min, the supernatant was discarded and the precipitate was left, and washed three times with sterile PBS solution and resuspended in sterile PBS solution. 10 μL of the resuspended bacterial solution was aspirated onto a glass slide, an anti-fluorescence quenching mounting medium was added, and an electric fluorescence microscope was used for observation.

[0025] Propidium iodide (PI) is a class of fluorescent dyes that can embed in DNA. When the cell membrane maintains its integrity, PI cannot enter the cell interior due to the blockage of the cell membrane. Once the cell membrane structure is damaged and its integrity is impaired, the PI dye can enter the cell and bind to DNA, thereby generating a fluorescent signal. Therefore, after the PI staining operation is completed, by monitoring the change of fluorescence intensity, it is possible to evaluate whether the cell membrane is damaged and the degree of damage. As shown in the figure, Stenotrophomonas acidaminiphila in the Nisin group showed less red fluorescence, and most of the cells with red fluorescence were observed after treatment with polypeptide NPAAKMSPKPATP. It indicates that polypeptide NPAAKMSPKPATP can change the cell membrane permeability, leading to cell death, and enabling the PI dye to enter the cell and bind to DNA, emitting red fluorescence.

[0026] The method for the biological preservative containing polypeptide NPAAKMSPKPATP is as follows: Take the polypeptide NPAAKMSPKPATP powder and dissolve it in sterile distilled water at 180 mg / mL, add 0.2% (w / v) of procyanidins and 0.5% (w / v) of agarooligosaccharides, and mix evenly to obtain a composite biological preservative.

[0027] Table 1 Formulation ratio of each experimental group solution

[0028] The following experiment was carried out on the biological preservative containing polypeptide NPAAKMSPKPATP: Verification of preservation effect: Fresh tilapia were used, each fish weighing 500 g ± 30 g, with a body length of 32 cm ± 0.5 cm and a body width of 14 cm ± 0.5 cm. Sterile distilled water was used as the blank control group. A certain number of tilapia fish slices were placed in each group of solutions (the mass ratio of fish slices to solution was 1:10) and soaked for 30 min under constant temperature conditions at 4°C. After soaking, the surface moisture of the samples was drained using a sterile operating table, vacuum-packed with sterile vacuum packaging bags, and stored under constant temperature conditions at 4°C. Samples were taken on the 0th, 1st, 3rd, 5th, and 9th days respectively for the determination of various indicators.

[0029] The fish slices were taken out and minced. Exactly 10.00 g of fish meat samples were weighed and 40 mL of pre-cooled protein buffer (10 mmol / L Na3PO4, 0.1 mol / L NaCl, 2 mmol / L MgCl2, 1 mmol / L EGTA, pH 7.0) was added. Homogenization was carried out at 10000 rpm for 1 min, with three pauses during this period. Subsequently, centrifugation was carried out at 5000 rpm and 4°C for 10 min. The supernatant was removed, and the precipitate was resuspended in 40 mL of buffer. The above extraction - centrifugation steps were repeated 3 times. Finally, the precipitate was resuspended in 40 mL of 0.1 mol / L NaCl solution, and homogenization treatment was carried out under the same conditions to remove connective tissues. After centrifugation at 4°C and 5000 rpm for 10 min, the collected precipitate was the purified myofibrillar protein.

[0030] 10 times the volume of 15 mmol / L PIPES buffer (containing 0.6 mol / L NaCl, pH 6.25) was added to the precipitate, homogenized at 10000 rpm for 1 min, left standing at 4°C for 30 min, filtered through two layers of gauze, and then centrifuged to collect the supernatant for storage at 4°C for subsequent determination. Experiment 1 - Effect on the total number of colonies of tilapia fish slices The reproduction of microorganisms is one of the important factors leading to the spoilage of aquatic products. Therefore, the freshness can be evaluated by the total number of colonies. According to the national health standard regulations, the total number of colonies in first-class fresh meat ≤ 10 6 CFU / g, the total number of colonies in second-class fresh meat ranges from 10 6 CFU / g - 10 8 CFU / g, when the total number of colonies reaches 10 8 CFU / g or more, it is determined to be spoiled meat.

[0031] The total number of colonies of refrigerated tilapia fillets under different treatment conditions is shown in the table. As the storage time increases, the total number of colonies continuously increases and shows an upward trend. At the 0th day, the initial total number of colonies in experimental group 1, experimental group 2, and experimental group 3 was 3.88±0.31 log CFU / g, 3.79±0.14 log CFU / g, and 3.84±0.05 log CFU / g, respectively, all at the level of first-class fresh meat; at the 5th day of storage, the total number of colonies in experimental group 1 and experimental group 2 was 7.30±0.56 log CFU / g and 6.81±0.01 log CFU / g, respectively, both at the level of second-class fresh meat. In experimental group 3, it was 5.72±0.15 log CFU / g, lower than the other two groups and at the level of first-class fresh meat; at the 9th day, the total number of colonies of the fillets in experimental group 3 reached 8.39±0.05 log CFU / g, reaching the degree of spoilage. Through comparison, it can be seen that experimental group 3 has significant advantages in inhibiting the growth of the total number of colonies of tilapia fillets and extending the shelf life. The polypeptide NPAAKMSPKPATP can inhibit the growth and reproduction of microorganisms, delay the deterioration of the quality of refrigerated tilapia fillets, and effectively extend its shelf life.

[0032]

[0033] Experiment 2 - Effect of compound biological preservatives on the degradation bands of myofibrillar proteins in tilapia fillets Samples of 3×3×3 mm were cut from the dorsal muscles of tilapia in each group and immersed in 10% formalin for 24 h for fixation to prevent tissue spoilage and maintain tissue morphology. After fixation, the tissue samples were dehydrated with ethanol at increasing concentrations (50%, 60%, 70%, 80%, 90%, 100%), with each concentration for about 1 h to remove the fixative and gradually make the tissue in an anhydrous state. After dehydration, the samples were embedded and sectioned. First, the tissue samples were immersed in paraffin solution with the cut surface facing down, and air bubbles should be avoided throughout the process. After infiltration was completed, the solution was poured into a mold and placed on a cooling table to solidify the paraffin. After shaping, the samples were taken out and sectioned with a microtome into thin slices about 5 μm thick. The sections were floated on a 40°C warm water bath to flatten them and attached to glass slides for observing and analyzing tissue structure. Subsequently, they were stained with hematoxylin and eosin, and after all treatments were completed, they were observed and photographed with an optical microscope.

[0034] It can be seen that in the early stage of storage, the structure of myofibrillar protein is compact, arranged neatly, and there are no obvious gaps; in the middle stage of storage, the myofibrillar protein tissues in each group become smaller, with clear boundaries, and gaps begin to appear; in the late stage of storage, larger extracellular spaces and irregular pores are observed in the myofibrillar protein structure of experimental group 1, while experimental group 2 and experimental group 2 inhibited the structural changes to varying degrees. Compared with experimental group 3, experimental group 2 maintained smaller and fewer gaps in the tissue, effectively reducing the structural disintegration during refrigeration. This result also reflects that the polypeptide NPAAKMSPKPATP can effectively inhibit the degradation of myofibrillar protein.

[0035] Experiment 3 - Observation on the Microstructure of Myofibrillar Protein Gel of Tilapia Fillets The treated myofibrillar protein was adjusted to 40 mg / mL with 15 mmol / L PIPES buffer (containing 0.6 mol / L NaCl, pH 6.25), filled into glass bottles, heated from 25 °C to 80 °C at a rate of 1 °C / min, maintained for 30 min of heating, cooled in a cold water bath, and then placed in a 4 °C refrigerator overnight for 12 h for use.

[0036] Take the gel sample to be tested, fix it in 2.5% (v / v) glutaraldehyde (0.1 M, pH 7.2) in a 4 °C refrigerator for 24 h, wash it three times with PBS buffer (0.1 M, pH 6.8), 10 min each time. Then dehydrate the gel sample three times with ethanol at concentrations of 40%, 50%, 60%, 70%, 80%, 90%, and 100%, 10 min each time. Then dry and sputter the sample with gold, and observe the microstructure of the sample under a scanning electron microscope at 500 times magnification.

[0037] The microstructure of the protein gel can reveal the interaction and aggregation degree of protein molecules, and can also reflect the degree of protein denaturation. The results show that the microstructures of experimental group 2 and experimental group 3 are compact and smooth, while the structure of experimental group 1 is the loosest and roughest. It shows that oxidation can damage the network structure of the protein gel, and experimental group 2 and experimental group 3 can inhibit protein oxidation, thereby inhibiting structural damage. After compounding, the network structure of the gel will be more uniform and the porosity will decrease, resulting in an improved texture of the gel. Compared with experimental group 3, experimental group 2 can form more connection points with protein molecules, enhancing the continuity and integrity of the gel network, indicating that on the one hand, the polypeptide NPAAKMSPKPATP can promote protein cross-linking and reduce the formation of large pores, and on the other hand, it can fill small pores, making the gel structure more uniform and dense.

[0038] As described above, it is only the preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, making equivalent substitutions or changes should be covered within the protection scope of the present invention.

Claims

1. A polypeptide NPAAKMSPKPATP, characterized in that: It includes the following steps: S1. Preparation of metabolites of Paenibacillus provencensis PP-2: Paenibacillus provencensis PP-2 is inoculated and streaked after the LB solid medium solidifies, and then placed in an incubator for inverted culture for 48 h. Single colonies are picked and inoculated into LB liquid medium, and cultured in a sterile shaker for 24 h. Then, it is inoculated into LB liquid medium at an addition amount of 1% and cultured for 7 d. Subsequently, it is centrifuged at 8000 r / min at 4 °C for 10 min, the precipitate is discarded and the supernatant is retained, and filtered and sterilized with a 0.22 μm filter membrane to obtain metabolites of Paenibacillus provencensis PP-2; S2. Isolation and purification of polypeptide NPAAKMSPKPATP from the metabolites in step S1: Gel column chromatography is used to further screen the antibacterial components of the metabolites of Paenibacillus provencensis PP-2 to obtain peptide segments, then the peptide sequence is identified, and the peptide sequence is analyzed. After analysis, polypeptide NPAAKMSPKPATP is synthesized.

2. The polypeptide NPAAKMSPKPATP according to claim 1, characterized in that: In step S2, the LC-MS method is used to identify the peptide sequence. The mobile phase A of the peptide sequence is 0.1% formic acid and 2% acetonitrile; the mobile phase B is 0.1% formic acid and 80% acetonitrile.

3. A polypeptide NPAAKMSPKPATP according to claim 1, characterized in that: In step S2, the de novo method is used to analyze the peptide sequence, and mass spectrometry analysis is carried out using a Q-Exactive HF-X mass spectrometer in the data-dependent acquisition mode.

4. A polypeptide NPAAKMSPKPATP according to claim 1, characterized in that: In step S2, polypeptide NPAAKMSPKPATP is synthesized by the Fmoc solid-phase synthesis method.

5. Application of a polypeptide NPAAKMSPKPATP according to any one of claims 1-4 in a biological preservative.

6. Use of the polypeptide NPAAKMSPKPATP according to claim 5 in a biological preservative, characterized in that: Preparation method of a biological preservative containing polypeptide NPAAKMSPKPATP: Take polypeptide NPAAKMSPKPATP powder and dissolve it with sterile distilled water, add procyanidins and agar oligosaccharides and mix evenly to obtain a composite biological preservative.

7. Use of the polypeptide NPAAKMSPKPATP according to claim 6 in a biological preservative, characterized in that: The concentration of the polypeptide NPAAKMSPKPATP powder after being dissolved with sterile distilled water is 180 mg / mL.

8. Use of the polypeptide NPAAKMSPKPATP according to claim 6 in a biological preservative, characterized in that: The mass concentration of the procyanidins is 0.2% w / v.

9. Use of the polypeptide NPAAKMSPKPATP according to claim 6 in a biological preservative, characterized in that: The mass concentration of the agar oligosaccharides is 0.5% w / v.

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