Lactobacillus plantarum LF001 and application thereof

Abstract

The invention discloses a lactobacillus plantarum LF001, the preservation number of the lactobacillus plantarum LF001 is GDMCC No.67171, and the lactobacillus plantarum LF001 integrates the functions of a high-efficiency fermentation agent and a high-efficiency biological preservative into a whole. According to the method, conventional lactic acid fermentation can be completed, the novel performance of high-yield antibacterial peptide can be achieved, broad-spectrum pathogenic bacteria and putrefying bacteria can be actively and effectively inhibited, the preservative and fresh-keeping effect which can only be achieved by common lactic acid bacteria and chemical preservatives / exogenous bacteriocin in the past can be achieved by using a single LF001 strain, the process is simplified, the cost is reduced, and the method is suitable for industrial production. And real'no chemical addition 'is realized.

Description

Technical Field

[0001] This invention relates to the field of microbial technology, and more specifically, to a Lactobacillus plantarum LF001 and its applications. Background Technology

[0002] If the lactic acid bacteria used during feed fermentation and in the storage and transportation stages after fermentation are not strong enough to quickly and effectively inhibit mold, yeast, and other putrefactive and pathogenic bacteria (such as Escherichia coli and Salmonella), the feed will become moldy and rancid, which will not only reduce its nutritional value but may also produce toxins that directly harm the health of farmed animals.

[0003] Many Lactobacillus plantarum strains used in fermented feed primarily function to produce acid and lower the pH value. However, relying solely on acid production limits their antibacterial spectrum and provides insufficient and lasting preservative effects. This invention aims to provide a strain that can not only rapidly produce acid but also simultaneously and efficiently secrete broad-spectrum antimicrobial peptides, achieving "dual protection" for feed and significantly improving fermentation success rate and product stability.

[0004] Under the "antibiotic-free" policy, the livestock industry urgently needs feed additives that can truly replace the growth-promoting and disease-preventing functions of antibiotics. Many existing probiotic products have mild effects and cannot achieve disease prevention effects comparable to antibiotics. This invention, through its potent antimicrobial peptides, directly targets and inhibits pathogenic bacteria in the gut, providing a superior solution for achieving "antibiotic-free farming."

[0005] In the field of fermented feed, existing solutions to the above problems mainly include: Using common fermentation agents: Fermentation is carried out using common strains of Lactobacillus plantarum, Lactobacillus acidophilus, etc., which mainly rely on organic acids such as lactic acid and acetic acid produced by their metabolism to inhibit other bacteria.

[0006] Combined use of chemical preservatives: Add additional chemical anti-mold agents such as calcium propionate and potassium sorbate to the fermented feed to prevent mold growth later.

[0007] Add other probiotics or antibacterial substances: compound Bacillus, yeast, etc. in feed, or directly add biological preservatives such as nisin and lysozyme.

[0008] Continued illegal or restricted use of antibiotics: In some areas with lax regulations, antibiotics are still being used illegally as growth promoters and preventative drugs.

[0009] Existing solutions have the following specific drawbacks when applied to fermented feed: 1. For common fermentation inoculants: Narrow and short-lived antibacterial spectrum: Common Lactobacillus plantarum mainly produces acid, resulting in poor inhibitory effects against acid-resistant bacteria (such as certain yeasts and molds). As the feed is ingested by animals and enters the neutral intestinal environment, its acidic antibacterial effect rapidly weakens. Insufficient competitiveness: In the complex microbial environment of feed, common strains may not be able to effectively compete with native microorganisms, leading to fermentation failure or secondary fermentation.

[0010] 2. For the combined use of chemical preservatives: Not labeled "all-natural": Adding chemical preservatives contradicts the original intention of fermented feed being "natural and green," affecting the product's selling points and value. Increased costs and process complexity: Requires additional equipment and mixing steps. Potentially affects feed palatability and intestinal microecology: Chemical preservatives may also have a slight inhibitory effect on beneficial bacteria in the animal's gut.

[0011] 3. Regarding the addition of other probiotics or antibacterial substances: High cost: Exogenous purified bacteriocins (such as Nisin) are very expensive and unsuitable for bulk feed products. Risk of interstrain antagonism: Complex combinations of bacterial agents may pose a risk of interstrain inhibition, affecting core fermentation functions. Delayed action: Exogenously added antimicrobial substances cannot establish an advantage in the early stages of fermentation like in-situ produced antimicrobial peptides.

[0012] 4. Regarding the illegal use of antibiotics: Legal risks and food safety hazards: This is a behavior that is expressly prohibited by the state, and it will result in drug residues and drug resistance, endangering public health. Summary of the Invention

[0013] To solve the above-mentioned technical problems, the present invention provides a *Lactobacillus plantarum* (… Lactiplantibacillus plantarum LF001, with accession number GDMCC No.67171.

[0014] In some embodiments of the present invention, the *Lactobacillus plantarum* ( Lactiplantibacillus plantarum LF001 is derived from pig manure.

[0015] This invention also provides a fermentation product, the preparation method of which includes: taking the above-mentioned *Lactobacillus plantarum* (… Lactiplantibacillus plantarum LF001 was used for liquid fermentation. After the fermentation was completed, the fermentation liquid was taken to obtain the fermentation product.

[0016] The present invention also provides the above-mentioned Lactobacillus plantarum ( Lactiplantibacillus plantarum The application of LF001 and / or the above-mentioned fermentation products in the production of antimicrobial peptides.

[0017] In some embodiments of the present invention, the antimicrobial peptide is a protein-based antimicrobial peptide.

[0018] The present invention also provides the above-mentioned Lactobacillus plantarum ( Lactiplantibacillus plantarum The use of LF001 and / or the above-mentioned fermentation products and / or the above-mentioned antimicrobial peptides in antibacterial and / or preservative purposes.

[0019] In some embodiments of the present invention, the antibacterial target is Gram-negative pathogens and Gram-positive pathogens.

[0020] The present invention also provides the above-mentioned Lactobacillus plantarum ( Lactiplantibacillus plantarum The application of LF001 and / or the above-mentioned fermentation products and / or the above-mentioned antimicrobial peptides in antibacterial and / or preservative purposes in fermented feed.

[0021] Effective gain: In the technical solution of this invention, strain LF001 integrates the functions of "high-efficiency fermentation agent" and "powerful biological preservative". It can not only complete conventional lactic acid fermentation, but its new property of "high production of antimicrobial peptides" enables it to actively and effectively inhibit a wide range of pathogens and putrefactive bacteria. The high-efficiency, broad-spectrum antimicrobial peptides secreted in situ by strain LF001 provide a more effective and long-lasting biological preservative guarantee than the simple acid effect. In addition, Lactobacillus plantarum LF001 can continuously produce antimicrobial peptides, which directly inhibit pathogenic bacteria such as Escherichia coli and Salmonella in the animal intestine, providing a definite solution for achieving antibiotic-free farming.

[0022] The LF001 single strain of the present invention can achieve the same preservation effect as in the past, which required "ordinary lactic acid bacteria + chemical preservatives / exogenous bacteriocins", simplifying the process, reducing costs, and achieving true "no chemical additives".

[0023] The strain of this invention not only acts as a preservative in feed containers, but also continues to secrete antimicrobial peptides in the intestines of animals after ingestion, inhibiting pathogens and thus playing a role in replacing antibiotics and promoting intestinal health, achieving a seamless connection from "feed preservation" to "animal health care". Attached Figure Description

[0024] To more clearly illustrate the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly described below. Obviously, the drawings described below are merely some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without any creative effort.

[0025] Figure 1 The colony morphology characteristics of the *Lactobacillus plantarum* strain LF001 of this invention; Figure 2 The present invention describes the individual morphological characteristics of the *Lactobacillus plantarum* strain LF001. Figure 3 The growth curve and pH value diagram of Lactobacillus plantarum LF001 strain provided in Example 1; Figure 4 Phylogenetic tree of 16S rDNA sequences of Lactobacillus plantarum LF001 and related model strains provided in Example 1 of this invention; Figure 5 Phylogenetic analysis of the recA gene sequence of Lactobacillus plantarum LF001 and related model strains provided in Example 1 of this invention; Figure 6 The Lactobacillus plantarum LF001 gene sequence provided in Example 1 of this invention; Figure 7 This is a bar chart showing the antibacterial effects of Lactobacillus plantarum LF001 on different plant Lactobacillus species provided in Example 2 of the present invention. Figure 8 This is a comparison of the antibacterial effect of Lactobacillus plantarum LF001 provided in Example 4 of the present invention in fermented feed. Detailed Implementation

[0026] This application discloses a *Lactobacillus plantarum* LF001 and its applications. Those skilled in the art can refer to this document and appropriately modify the process parameters to achieve the desired results. It should be particularly noted that all similar substitutions and modifications are obvious to those skilled in the art and are considered to be included in this invention. The methods and applications of this invention have been described through preferred embodiments. Those skilled in the art can clearly modify or appropriately change and combine the methods and applications described herein without departing from the content, spirit, and scope of this application to realize and apply the technology of this invention.

[0027] It should be understood that the expression “one or more of…” individually includes each of the objects described after the expression, as well as various different combinations of two or more of the described objects, unless otherwise understood from the context and usage. The expression “and / or” combined with three or more described objects should be understood to have the same meaning, unless otherwise understood from the context.

[0028] The terms “including,” “having,” or “containing,” including the use of their grammatical synonyms, should generally be understood as open-ended and non-restrictive, for example, not excluding other unstated elements or steps, unless otherwise specifically stated or understood from the context.

[0029] It should be understood that the order of steps or the sequence of actions is not important as long as this application remains operational. Furthermore, two or more steps or actions can be performed simultaneously.

[0030] The use of any and all instances or exemplary language such as “e.g.” or “include” in this document is intended merely to better illustrate the application and does not constitute a limitation on the scope of the application. No language in this specification should be construed as indicating that any unclaimed element is essential to the practice of this application.

[0031] Furthermore, the numerical ranges and parameters used to define this application are approximate values, and the relevant values ​​in the specific embodiments have been presented as precisely as possible. However, any numerical value inevitably contains standard deviations due to individual test methods. Therefore, unless otherwise explicitly stated, it should be understood that all ranges, quantities, values, and percentages used in this disclosure are modified with the word "approximately." Here, "approximately" generally means that the actual value is within 10%, 5%, 1%, or 0.5% of a specific value or range.

[0032] Unless otherwise specified, the raw materials, reagents, consumables and instruments involved in this application are all commercially available products and can be purchased from the market.

[0033] This invention provides a *Lactobacillus plantarum* ( Lactiplantibacillus plantarum LF001, with accession number GDMCC No. 67171. *Lactobacillus plantarum* ( Lactiplantibacillus plantarum Lactobacillus plantarum LF001 (hereinafter referred to as Lactobacillus plantarum LF001) is a genera of Lactobacillus plantarum.

[0034] Lactobacillus plantarum LF001 is derived from pig feces. It is Gram-positive, and its colonies are milky white, smooth, with obvious ridges and regular edges. Under microscopic morphology, it is rod-shaped and has no spores or flagella.

[0035] According to another aspect of the present invention, a fermentation product is also provided, the preparation method of which includes: liquid fermentation of the above-mentioned Lactobacillus plantarum LF001, and taking the fermentation broth after the fermentation is completed to obtain the fermentation product.

[0036] In some specific embodiments, liquid fermentation includes pre-culturing *Lactobacillus plantarum* LF001, and then inoculating the pre-cultured *Lactobacillus plantarum* LF001 into a liquid culture medium for liquid fermentation. In some specific embodiments, the pre-culturing includes inoculating a single colony of *Lactobacillus plantarum* LF001 into the liquid culture medium and culturing it for at least 24 hours. In some specific embodiments, the inoculum amount of the pre-cultured *Lactobacillus plantarum* LF001 inoculated into the liquid culture medium is 0.05 wt% to 0.15 wt%, preferably 0.1 wt%.

[0037] MRS medium can be used for the liquid culture medium of Lactobacillus plantarum LF001.

[0038] In some specific embodiments, a single colony of strain LF001 is picked and inoculated into 20 mL of liquid MRS medium and cultured overnight at 37°C and 150 rpm to serve as the seed culture. The seed culture is then inoculated into 3 L of liquid MRS medium at an inoculation rate of 0.1 wt% and cultured statically at 37°C for 72 h to obtain the fermentation product of Lactobacillus plantarum LF001.

[0039] According to another aspect of the present invention, an antimicrobial peptide is also provided, comprising the above-described Lactobacillus plantarum LF001 or the above-described fermentation product.

[0040] Among them, antimicrobial peptides are proteins.

[0041] According to another aspect of the present invention, the use of the above-mentioned Lactobacillus plantarum LF001, the above-mentioned fermentation product, or the above-mentioned antimicrobial peptide in inhibiting and / or preserving putrefactive bacteria is also provided.

[0042] The plant lactobacillus LF001 can inhibit putrefactive bacteria including Staphylococcus aureus, Escherichia coli, Listeria, Bacillus subtilis, Pseudomonas aeruginosa, Enterococcus faecalis, Salmonella, and Salmonella typhimurium.

[0043] According to another aspect of the present invention, the use of the above-mentioned Lactobacillus plantarum LF001, the above-mentioned fermentation product, or the above-mentioned antimicrobial peptide in antibacterial and / or preservative purposes in fermented feed is also provided.

[0044] The present invention will be further illustrated by the following examples. Unless otherwise specified, the materials in the examples are prepared according to existing methods or purchased directly from the market.

[0045] GYP solid culture medium consists of the following components by weight percentage: glucose 1%, peptone 0.5%, beef extract 0.2%, yeast extract 1%, sodium acetate 0.2%, Tween 80 0.1%, diammonium citrate 0.1%, magnesium sulfate 0.02%, manganese sulfate 0.005%, agar powder 1.5%, calcium carbonate 0.5%, and the balance being distilled water.

[0046] MRS solid culture medium consists of the following components by weight percentage: glucose 1%, peptone 0.5%, beef extract 0.2%, yeast extract 1%, sodium acetate 0.2%, Tween 80 0.1%, diammonium citrate 0.1%, magnesium sulfate 0.02%, manganese sulfate 0.005%, agar powder 1.5%, and the balance being distilled water.

[0047] LB agar medium: 1% tryptone, 1% sodium chloride, 0.5% yeast extract, 2% agar powder, pH adjusted to 7.0±0.1, the remainder being distilled water.

[0048] Example 1 1.1 Isolation and Identification of Lactic Acid Bacteria The pig fecal samples were diluted 10-fold with sterile physiological saline. 100 μL of the kimchi brine dilutions (10⁻⁴, 10⁻⁵, and 10⁻⁶ dilutions) were spread onto GYP solid medium and incubated at 37°C for 48 h. Single colonies forming clear zones were picked and repeatedly isolated and purified using the streak plating method. The morphological characteristics of each colony were recorded, and Gram staining was performed for microscopic examination.

[0049] like Figure 1 and Figure 2 As shown, the colony morphology of strain LF001 is as follows: the colonies are milky white, round, raised, smooth, and have neat edges. The individual morphology of strain LF001 is as follows: Gram-positive (G+), short rod-shaped, single or in pairs, without spores, and without flagella.

[0050] 1.2 Growth curve of strain LF001 A single colony of strain LF001 was picked and inoculated into 20 mL of liquid MRS medium and cultured overnight at 37°C and 150 rpm to serve as the seed culture. The seed culture was then inoculated into 3 L of liquid MRS medium at a rate of 0.1 wt% and incubated statically at 37°C for 72 h. During the incubation period, 100 mL samples were taken every 6 h to determine the pH of the bacterial suspension and the absorbance at OD600 nm using a spectrophotometer.

[0051] The results are as follows Figure 3 As shown, strain LF001 exhibits a typical growth curve: it is in the lag phase for the first 12 hours, in the logarithmic growth phase from 12 to 24 hours, and enters the stationary phase after 24 hours. Throughout the fermentation process, the pH of the fermentation broth gradually decreases from pH 6.8, eventually stabilizing at around pH 3.4.

[0052] 1.3 Identification of microbial strains The LF001 strain was inoculated into MRS liquid medium and cultured at 37°C for 12 h. Using the bacterial culture as a template, 16S rDNA was amplified using 27F (SEQ ID No. 1) and 1495R (SEQ ID No. 2) primers, and the PCR amplification products were sequenced for analysis.

[0053] The 16S rDNA sequence of strain LF001 obtained is as follows: Figure 4 , Figure 5 and Figure 6As shown, BLAST alignment analysis was performed in the NCBI database. The results showed that the 16S rRNA gene sequence obtained from sample LF001 was 1374 bp. Nucleotide homology comparison with already registered sequences in Genebank using the BLAST program showed that the 16S rRNA gene sequence of this bacterium had 99.60% homology with Lactobacillus plantarum. Therefore, strain LF001 is identified as Lactobacillus plantarum and named LF001. It was deposited on October 27, 2025, at the China General Microbiological Culture Collection Center (GDMCC, address: 5th Floor, Building 59, No. 100 Xianlie Middle Road, Guangzhou), with accession number GDMCCNo. 67171.

[0054] Example 2 2.1 Antibacterial activity of bacterial cells To further analyze the antibacterial compounds of LF001, the pH of the fermentation supernatant of strain LF001 was adjusted to 6.0 using sodium hydroxide to eliminate the potential antibacterial effect of organic acids. Subsequently, the fermentation supernatant was treated with catalase, trypsin, and pepsin, respectively, as follows: Catalase treatment method: Catalase was added to the fermentation supernatant at a final concentration of 10 mg / mL to eliminate the influence of hydrogen peroxide; Treatment of pepsin and trypsin: Pepsin and trypsin were added to the fermentation supernatant at a final concentration of 1 mg / mL. The pH of the supernatant was adjusted to the optimal pH of 2.0 for pepsin and 8.0 for trypsin. The fermentation broths treated with enzymes were incubated in a water bath at 37°C for 2 hours. Then the pH of the supernatant was adjusted back to the original pH value. After the above treatment, the inhibition zone experiment was carried out using the same method as described above, with the untreated fermentation supernatant as a blank control. The results are shown in Table 1.

[0055] Table 1. Analysis of antimicrobial substances in Lactobacillus plantarum LF001 Table 1 shows that after pH adjustment or catalase treatment, the antibacterial activity of strain LF001 decreased slightly but not significantly, indicating that organic acids have little effect on antibacterial activity and that hydrogen peroxide is not the main antibacterial component in the fermentation supernatant of strain LF001. However, after treatment with trypsin or pepsin, the antibacterial activity decreased significantly. This suggests that the main antibacterial component in the fermentation supernatant of strain LF001 is protein-like, and it is speculated that there may be protein-like antibacterial peptides in the fermentation supernatant of strain LF001.

[0056] 2.2 Antimicrobial activity of antimicrobial peptides secreted by LF001 into the fermentation broth Four strains of *Lactobacillus plantarum* (numbered B01, B02, B03, and B04) were purchased from the market and cultured with the *Lactobacillus plantarum* strain LF001 of this invention. Each strain was inoculated into 200 ml of MRS liquid medium and cultured at 37°C for 36 h. The cell-free supernatant was then collected by centrifugation. The antibacterial properties of each *Lactobacillus plantarum* strain were determined using the Oxford cup method, with *Staphylococcus aureus*, *Escherichia coli*, *Listeria*, *Bacillus subtilis*, *Pseudomonas aeruginosa*, *Enterococcus faecalis*, *Salmonella*, and *Salmonella typhimurium* as indicator bacteria. The specific procedure is as follows: Mix the standard indicator bacteria (1.0×10⁷ CFU / mL, as shown in Table 1) with LB agar medium, punch holes in Oxford cups (8 mm in diameter), add 200 μL of supernatant, and incubate at 37°C for 12 h. Measure the diameter of the inhibition zone to evaluate the antibacterial activity.

[0057] The results are as follows Figure 7 As shown in Table 2, all five strains exhibited significant broad-spectrum antibacterial activity, with specific results illustrating their effectiveness in inhibiting the growth of various Gram-positive and Gram-negative bacteria. Among them, strains B01, B02, B03, and B04 showed inhibition zones ranging from 14 to 18 mm against most indicator bacteria, with some showing inhibition zones smaller than 14 mm. In contrast, strain LF001 exhibited inhibition zones ranging from 22 to 30 mm against most indicator bacteria, demonstrating broad-spectrum and potent antibacterial activity.

[0058] Table 2. Statistical analysis of the antibacterial effects of different Lactobacillus plantarum strains. Example 3 Inhibitory effects of Lactobacillus plantarum LF001 antimicrobial peptides on various pathogenic bacteria in fermented feed: (1) The inhibitory effect of Lactobacillus plantarum LF001 antimicrobial peptides on multiple pathogenic bacteria in fermented feed: Lactobacillus plantarum LF001 bacterial solution was prepared by the method described in Example 2. The supernatant containing antimicrobial peptides produced by Lactobacillus plantarum LF001 was obtained by centrifugation. The ability of it to control multiple pathogenic bacteria in fermented feed was determined according to the following steps: Prepare fermented feed according to the table below; Prepare 18kg of fermented feed carrier according to the table below, and divide it into 9 bags, each bag weighing 2kg: (2) Escherichia coli, Listeria, and Salmonella cultured to OD600nm=0.5 were resuspended in physiological saline at a concentration of 106 CFU / mL. The suspensions of these three bacteria were then mixed in a volume ratio of 1:1:1 to obtain a mixture of pathogenic bacteria. (3) Take 6 bags of fermented feed substrate from step (1), pour 200ml of pathogenic bacteria mixture from step (2) into each bag, and mix thoroughly. Three portions of bacterial supernatant containing pathogenic bacteria are mixed thoroughly and are the antimicrobial treatment group. The other three portions of fermented feed substrate containing pathogenic bacteria are added to 400ml of fresh MRS medium and mixed thoroughly and are the non-antimicrobial treatment group. The remaining three portions of fermented feed substrate from step (1) are added to 200ml of physiological saline and 400ml of fresh MRS medium and mixed thoroughly and are the control group. (4) Starting from day 0, samples were taken and tested every 24 hours. 50g of each fermented feed was taken from each group and tested for a total of 10 days. The test method was as follows: the fermented feed was placed in an Erlenmeyer flask and 50mL of sterile physiological saline was added to the Erlenmeyer flask. The flask was then shaken for 1 minute on a shaker. 1mL of the sample solution was taken into a 1.5mL centrifuge tube and serially diluted 10 times with physiological saline. Each sample was diluted to 10⁻⁷. Four appropriate dilutions were selected for each of the three groups. 100μL of the diluted solution was taken and spread on LB medium. At the same time, the diluted solutions of the antimicrobial treatment group and the non-antimicrobial treatment group were spread on Salmonella selective medium (bismuth sulfite agar), Escherichia coli selective medium (MacConkey medium), and Listeria selective medium (PALCAM medium), respectively. Three plates were repeated for each dilution. After spreading, the plates were placed at 37℃ and incubated for 24-48 hours. Colony counting was performed at dilutions with 30-300 colonies.

[0059] The results are as follows Figure 8 As shown, for the total number of colonies ( Figure 8 A) In the control group, the total bacterial count of the fermented feed gradually increased with prolonged storage time, approaching that of the antibiotic-free treatment group. Compared with the antibiotic-free treatment group, the total bacterial count in the antibiotic-treated group was below the detection limit on both day 0 and day 10, meaning that antibiotic treatment reduced the total bacterial count by more than 99.99%. For *Escherichia coli* (… Figure 8 (B) In the group without antibiotic treatment, the count peaked on day 6 with increasing storage time and remained at a high level from day 6 to day 10. In contrast, in the antibiotic-treated group, the viable E. coli count remained below the detection limit throughout the 10-day storage period. Regarding Listeria monocytogenes (…),… Figure 8 C) In the group without antibiotic treatment, the viable count of Listeria monocytogenes gradually increased during the 0-5 day storage period, peaking on day 5, and stabilizing between days 6-10. In the antibiotic-treated group, the viable count remained below the detection limit throughout. For Salmonella (… Figure 8D) In ​​the untreated group, the colony count increased rapidly within 2 days and remained at a high level for 3-10 days. In contrast, in the antibiotic-treated group, the Salmonella viable count remained below the detection limit throughout the 10-day storage period. This demonstrates that the Lactobacillus plantarum LF001 broad-spectrum antimicrobial metabolite mixture can completely inhibit the growth of Gram-negative pathogens (Escherichia coli, Salmonella) and Gram-positive pathogens (Listeria).

[0060] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A type of Lactobacillus plantarum ( Lactiplantibacillus plantarum LF001, characterized in that, The accession number is GDMCC No. 67171.

2. The *Lactobacillus plantarum* according to claim 1 ( Lactiplantibacillus plantarum LF001, characterized in that, The plant lactobacillus ( Lactiplantibacillus plantarum LF001 is derived from pig manure.

3. A fermentation product, characterized in that, The preparation method includes: using the *Lactobacillus plantarum* as described in claim 1 or 2 (… Lactiplantibacillus plantarum LF001 was used for liquid fermentation. After the fermentation was completed, the fermentation liquid was taken to obtain the fermentation product.

4. The *Lactobacillus plantarum* as described in claim 1 or 2 ( Lactiplantibacillus plantarum The application of the fermentation product as described in LF001 or claim 3 in the production of antimicrobial peptides.

5. The application according to claim 4, characterized in that, The antimicrobial peptide is a protein-based antimicrobial peptide.

6. The *Lactobacillus plantarum* according to claim 1 or 2 ( Lactiplantibacillus plantarum LF001, the application of the fermentation product of claim 3 or the antimicrobial peptide of claim 4 or 5 in antibacterial and / or preservative purposes.

7. The application according to claim 6, characterized in that, The targets of the antibacterial activity are Gram-negative pathogens and Gram-positive pathogens.

8. The *Lactobacillus plantarum* according to claim 1 or 2 ( Lactiplantibacillus plantarum LF001, the application of the fermentation product of claim 3 or the antimicrobial peptide of claim 4 or 5 in antibacterial and / or preservative purposes in fermented feed.

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