A kind of Lactobacillus plantarum HP-ZW2 and its application

Abstract

The present application relates to the field of biotechnology, and specifically discloses a plant lactobacillus HP-ZW2 and its application. A plant lactobacillus HP-ZW2 (Lactobacillus plantarumHP-ZW2), the strain is deposited in the China Center for Type Culture Collection, the depository address is Wuhan University, Wuhan, China, the deposit number is CCTCCNO: M20221790, and the deposit date is November 14, 2022. The present application also provides the application of plant lactobacillus HP-ZW2 in the preparation of shrimp feed, which improves the intestinal health of shrimp, promotes the growth of shrimp, and increases the survival rate of shrimp.

Description

Technical Field

[0001] The present application relates to the field of biotechnology, and more specifically, to a Lactobacillus plantarum HP-ZW2 and an application thereof. Background Art

[0002] Lactobacillus plantarum is a lactic acid bacterium belonging to the genus Lactobacillus. It is a probiotic that is widely found in the natural environment, food, and animal intestines. Lactobacillus plantarum has multiple biological functions and health benefits, including regulating the balance of intestinal flora, enhancing immunity, inhibiting the growth of pathogens, producing antibacterial substances, degrading harmful substances, and promoting the absorption of nutrients.

[0003] In the feed industry, Lactobacillus plantarum HP-ZW2 can be used to ferment feed to improve the nutritional value and flavor of feed. Crayfish has delicate meat, delicious taste, rich nutrition and unique flavor, making it a favorite table delicacy. In the process of breeding crayfish, feed is usually used, which has the advantages of comprehensive and balanced nutrition, increased growth rate and enhanced survival rate. However, due to the deterioration of water ecology, more and more crayfish intestinal diseases such as enteritis and white stool are caused, which seriously affects the vitality of shrimp intestinal immune cells, leading to a significant increase in the mortality rate of crayfish. Summary of the invention

[0004] In order to improve the problem of increasing intestinal diseases in crayfish, which leads to a significantly increased mortality rate of crayfish, the present application provides a Lactobacillus plantarum HP-ZW2 and its application.

[0005] In the first aspect, the present application provides a Lactobacillus plantarum HP-ZW2 (Lactobacillus plantarumHP-ZW2), which is deposited in the China Center for Type Culture Collection, the address of the depository is Wuhan University, Wuhan, China, the deposit number is CCTCCNO: M20221790, and the deposit date is November 14, 2022.

[0006] By adopting the above technical solution, Lactobacillus plantarum HP-ZW2 has good acid resistance, helps to play a probiotic role in the digestive tract, can produce lactic acid and hydrogen peroxide, helps to maintain the balance of intestinal microecology, inhibits the growth of harmful bacteria, promotes intestinal health, and has a relatively wide application value.

[0007] In a second aspect, the present application provides an application of Lactobacillus plantarum HP-ZW2 in preparing shrimp feed.

[0008] By adopting the above technical scheme, Lactobacillus plantarum HP-ZW2 can be used as a feed additive to improve the digestibility of shrimp for feed, reduce the feed coefficient, and promote the growth and survival of shrimp; it can also increase the thickness of shrimp intestinal epithelial cells, promote intestinal health, increase digestive enzyme activity, help the absorption of nutrients, and promote shrimp growth; it can also help improve the quality of aquaculture water, reduce the accumulation of harmful substances, and create a more suitable growth environment.

[0009] Optionally, the shrimp feed includes the following raw materials in parts by weight: 28-33 parts of fish meal, 1-3 parts of multivitamins, 2-5 parts of soybean lecithin powder, 18-22 parts of fermented material, 4-8 parts of pineapple extract, 1-2 parts of monocalcium phosphate, and 2-4 parts of sucrose;

[0010] The raw materials of the fermented product include elodea, lotus root powder, protein powder and the plant lactobacillus HP-ZW2.

[0011] By adopting the above technical solutions, fish meal is rich in high-quality protein and fatty acids, providing essential amino acids for shrimp growth. The nutrients are easy to digest and absorb, which helps to improve the utilization rate of shrimp feed and promote growth. It can also reduce the nitrogen content in shrimp excrement, help improve aquaculture water quality, and reduce environmental pollution. Multivitamins provide a variety of vitamins required for shrimp growth, help promote the growth and development of shrimp, enhance shrimp immunity, increase its growth rate and survival rate, and shorten the breeding cycle.

[0012] Soybean lecithin powder can make up for the low fat digestion ability of young shrimps due to lack of bile, and help improve the digestion and absorption efficiency of fat. Bromelain in pineapple extract can decompose protein and improve the digestion and absorption efficiency of shrimps to protein in feed, thereby improving feed utilization, enhancing shrimps' immunity, improving intestinal health, and improving growth performance. Calcium dihydrogen phosphate can provide the minerals necessary for shrimps' growth and development, and improve the hardness and strength of shrimp shells. Sucrose regulates the palatability of feed, enhances shrimps' appetite, and promotes their feeding.

[0013] In the fermentation product, Elodea, lotus root powder and protein powder are used as raw materials for fermentation, providing a variety of nutrients required for shrimp growth, including protein, amino acids, vitamins and minerals. The beneficial bacteria and enzymes produced in the fermentation process can improve the intestinal microecology of shrimp, promote intestinal health, improve the digestion and absorption rate of feed, promote the growth and development of shrimp, enhance the immunity of shrimp, improve the water quality of aquaculture water, and thus increase the growth rate of shrimp. Plant lactobacillus HP-ZW2 can grow and reproduce rapidly in the fermentation matrix, start the fermentation process, and ensure the smooth progress of fermentation. During the fermentation process, nutrients such as vitamin B group, amino acids, peptides, etc. can be synthesized to improve the nutritional value of fermented food. Antimicrobial peptides, bacteriocins and other substances produced by plant lactobacillus HP-ZW2 can inhibit the growth of pathogens and spoilage bacteria, protect fermented food from contamination, and extend the shelf life.

[0014] Optionally, the mass ratio of the fish meal, the fermented product and the pineapple extract is 4-7:3-5:1.

[0015] By adopting the above technical scheme, the mass ratio of fish meal, fermentation product and pineapple extract is further limited within a certain range. Fish meal is rich in high-quality protein and fatty acids. The fermentation product has a high nutritional value, provides additional nutrition, improves digestion and absorption of shrimps, optimizes intestinal microecology, enhances immunity, improves water quality, and thus helps shrimps absorb and eat fish meal. Pineapple extract not only provides the fiber required for shrimp growth, but also promotes shrimp digestion and helps them eat more. The combination of fish meal, fermentation product and pineapple extract helps shrimps eat and promotes their growth.

[0016] Optionally, the method for preparing the fermented product comprises the following steps:

[0017] S1, grinding Elodea, lotus root powder and protein powder separately, and then mixing to obtain a mixture;

[0018] S2. Disperse the mixture in water, add Lactobacillus plantarum HP-ZW2 at an inoculum amount of 3×107-6×107 cfu / L, and ferment at a temperature of 36-38°C for 24-26h to obtain a fermentation product.

[0019] By adopting the above technical solutions, Elodea contains rich nutrients, including protein, carbohydrates, vitamins and minerals, which can be converted into beneficial metabolites during the fermentation process. As a fermentation raw material, the metabolites of Elodea can promote the growth of aquatic animals such as river crabs and lobsters, and improve their yield and quality. During the fermentation process, Elodea can absorb nutrients such as nitrogen and phosphorus in the water, which helps to improve water quality and reduce eutrophication of water bodies.

[0020] Lotus root powder is used as a fermentation raw material to promote fermentation, natural preservation, and improve nutritional value. Lotus root powder is rich in nutrients such as starch, protein, vitamins and minerals. These ingredients can serve as a high-quality matrix for microbial growth during the fermentation process and promote fermentation efficiency. The amino acids in protein powder can be converted into more complex metabolites such as amino acids, peptides, vitamins, etc. during the fermentation process, thereby improving the nutritional value and functionality of the fermentation products. Protein powder is rich in amino acids, which can promote microbial activity and metabolic efficiency during the fermentation process.

[0021] The combination of Elodea, lotus root powder and protein powder not only provides nutrients, but also helps to improve the fermentation efficiency. As a fermentation agent, Lactobacillus plantarum HP-ZW2 can quickly grow and reproduce in the fermentation matrix, start the fermentation process, and ensure the smooth progress of fermentation. The fermented product has rich nutritional value and promotes the growth of shrimp.

[0022] Optionally, the mass ratio of the Elodea, lotus root powder and protein powder is 1:0.4-0.6:0.2-0.3.

[0023] By adopting the above technical scheme, the mass ratio of Elodea, lotus root powder and protein powder is further limited, and the obtained fermentation product has high nutritional value, which is conducive to the growth of shrimps and improves water quality. Elodea contains protein, carbohydrates, vitamins and minerals, etc., and can absorb nutrients such as nitrogen and phosphorus in the water during the fermentation process, which helps to improve water quality; lotus root powder is rich in nutrients such as starch, protein, vitamins and minerals, which promotes fermentation efficiency; the amino acids in the protein powder can be converted into more complex metabolites during the fermentation process, which promotes the microbial activity and metabolic efficiency during the fermentation process.

[0024] Optionally, the preparation method of the pineapple extract comprises the following steps:

[0025] (1) Peeling, washing, crushing and filtering the pineapple to obtain juice, dispersing the juice in deionized water, adding ginger juice and pectinase for enzymolysis, wherein the enzymolysis temperature is 40-45° C., the enzymolysis time is 3-4 h, after the enzymolysis is completed, inactivating the enzyme at 90° C. for 30 min, filtering and obtaining an extract;

[0026] (2) dispersing the extract in acetic acid solution, stirring at 70-80° C. for 1-2 h, adding chitosan and modified shell powder, stirring for 2-3 h, drying and grinding to obtain pineapple extract.

[0027] By adopting the above technical scheme, ginger juice is added to pineapple juice, and the enzyme components contained in ginger juice and pineapple juice respectively. Pineapple juice contains bromelain, and ginger juice contains gingerol and gingerol, etc. These components cooperate to improve the activity of pectinase, promote the enzymolysis of pectinase, and improve the enzymolysis efficiency.

[0028] The enzymatically hydrolyzed extract is dispersed in an acetic acid solution and chitosan is added. Chitosan has natural antibacterial properties, can inhibit the growth of a variety of bacteria and fungi, has antioxidant capacity, can scavenge free radicals, protect the active ingredients in the pineapple extract from oxidative damage, and extend its shelf life. Subsequently, the antibacterial activity of shrimp feed is improved, immune function is enhanced, intestinal health is promoted, and growth performance is improved.

[0029] The modified shell powder can be dispersed in the pineapple extract, and chitosan has a certain viscosity. In the obtained pineapple extract, the extract is closely connected with the modified shell powder, which helps to improve the comprehensive nutritional value of the extract. The modified shell powder is rich in calcium and can be used as a supplementary source of calcium to improve the nutritional value of the pineapple extract, which helps to subsequently increase the calcium content of the shrimp feed. The shell powder acts as a stabilizer to help maintain the structure and function of the pineapple extract. It also has a certain antibacterial activity, which helps to inhibit the growth of microorganisms in the pineapple extract and prolong its shelf life. The prepared pineapple extract has high antibacterial properties and nutritional value, which helps to subsequently improve the corresponding performance of the shrimp feed.

[0030] Optionally, the mass ratio of the extract, chitosan and modified shell powder is 1:0.3-0.5:0.4-0.6.

[0031] By adopting the above technical scheme, the mass ratio of the extract, chitosan and modified shell powder is further limited within a certain range, thereby improving the nutritional value and antibacterial properties of the extract, and subsequently improving the corresponding performance of the shrimp feed. The extract is closely connected with the modified shell powder, which helps to improve the comprehensive nutritional value of the extract. The modified shell powder is rich in calcium and can be used as a supplementary source of calcium. The combination of the extract, chitosan and modified shell powder has high antibacterial properties and nutritional value, which helps to subsequently improve the corresponding performance of the shrimp feed.

[0032] Optionally, the preparation method of the modified shell powder includes the following steps: dispersing the shell powder in a sodium hydroxide solution, stirring for 1-2 hours, washing with water, drying, and then dispersing the shell powder in deionized water, adding xanthan gum and astragalus powder, stirring at a temperature of 80-85°C for 1-2 hours, and drying to obtain modified shell powder.

[0033] By adopting the above technical solution, sodium hydroxide erodes the shell powder to a certain extent, improves the porosity and adsorption of the shell powder, and helps the adsorption of the shell powder. Xanthan gum has a certain viscosity, so that the astragalus powder is stably loaded on the surface of the shell powder, which improves the nutritional value and antibacterial activity of the shell powder. Moreover, the antibacterial activity of the shell powder is combined with the stability of xanthan gum, which may enhance the antiseptic ability of the system and extend the shelf life of the product. In addition, the combination of calcium in the shell powder and xanthan gum can improve the nutritional value of the product. At the same time, the characteristics of xanthan gum help to improve the taste and texture of the mixture and promote shrimp eating.

[0034] Astragalus powder is rich in various nutrients, such as flavonoids, polysaccharides, amino acids, etc., which, combined with calcium in shell powder, can provide a more comprehensive nutritional supplement, which helps to supplement the nutrients needed by shrimp. It also has antibacterial and antiseptic properties, which may help to enhance the antiseptic ability of the system and extend the shelf life of the product while maintaining the medicinal value of astragalus powder. The modified shell powder obtained by combining various components has a more comprehensive nutritional value and extends the storage period of shrimp feed.

[0035] Optionally, the mass ratio of the shell powder, xanthan gum and astragalus powder is 1:0.05-0.07:0.1-0.2.

[0036] By adopting the above technical scheme, the mass ratio of shell powder, xanthan gum and astragalus powder is further limited within a certain range, and the obtained modified shell powder has a higher nutritional value. Shell powder is rich in calcium, and astragalus powder is rich in various nutrients, such as flavonoids, polysaccharides, amino acids, etc., which combined with the calcium in shell powder can provide a more comprehensive nutritional supplement. Xanthan gum has a certain viscosity, which makes the astragalus powder stably loaded on the surface of shell powder, thereby improving the nutritional value and antibacterial activity of shell powder. The combination of the three improves the nutritional value and antibacterial activity of the mixture.

[0037] In summary, this application has the following beneficial effects:

[0038] 1. The present application provides a Lactobacillus plantarum HP-ZW2, which has good acid resistance, helps to play a probiotic role in the digestive tract, can produce lactic acid and hydrogen peroxide, helps to maintain the balance of intestinal microecology, inhibits the growth of harmful bacteria, promotes intestinal health, and has a wide range of application value.

[0039] 2. The present application provides an application of Lactobacillus plantarum HP-ZW2 in the preparation of shrimp feed. As a feed additive, Lactobacillus plantarum HP-ZW2 can improve the digestibility of shrimp for feed, reduce the feed coefficient, and promote the growth and survival of shrimp; it can also increase the thickness of shrimp intestinal epithelial cells, promote intestinal health, increase digestive enzyme activity, help the absorption of nutrients, and promote the growth of shrimp.

[0040] 3. In the fermentation product of the present application, Elodea, lotus root powder and protein powder are used as fermentation raw materials to provide a variety of nutrients required for shrimp growth, including protein, amino acids, vitamins and minerals. The beneficial bacteria and enzymes produced during the fermentation process can improve the intestinal microecology of shrimp, promote intestinal health, and improve the digestion and absorption rate of feed. It can promote the growth and development of shrimp, enhance the immunity of shrimp, and improve the water quality of aquaculture water, thereby increasing the growth rate of shrimp. DETAILED DESCRIPTION

[0041] Example

[0042] 1. Culture medium

[0043] MRS solid culture medium: peptone 10.0 g, beef extract 10.0 g, yeast extract powder 5.0 g, glucose 20.0 g, Tween-80 1.0 mL, K2HPO4·3H2O, anhydrous sodium acetate 5.0 g, diammonium citrate 2.0 g, MnSO4·H2O 0.058 g, MgSO4·7H2O 0.29 g, agar 15.0 g. Add the above ingredients into distilled water, make up to 1000 mL, heat to dissolve, adjust the pH to 6.4, and sterilize at 121°C for 20 min after aliquoting.

[0044] MRS liquid culture medium: peptone 10.0g, beef extract 10.0g, yeast extract powder 5.0g, glucose 20.0g, Tween-80 1.0mL, K2HPO4·3H2O, anhydrous sodium acetate 5.0g, diammonium citrate 2.0g, MnSO4·H2O 0.058g, MgSO4·7H2O 0.29g. Add the above ingredients into distilled water, make up to 1000mL, heat to dissolve, adjust the pH to 6.4, and sterilize at 121℃ for 20min after aliquoting.

[0045] Rescreening culture medium: (lower layer) 1.5% plain agar, (upper layer) 10.0 g peptone, 5.0 g yeast extract, 10.0 g sodium chloride, 20.0 g agar. Add the above ingredients into distilled water, make up to 1000 mL, heat to dissolve, and sterilize at 121°C for 20 min after aliquoting.

[0046] 2. Isolation of lactic acid bacteria strains

[0047] Under sterile conditions, 10.0 g of kimchi was placed in 90.0 mL of sterile physiological saline, and fully shaken for 5 minutes. A ring was picked with an inoculation loop and streaked on a 1.0% CaCO3 MRS solid medium, and cultured at 37°C for 48 hours. White colonies with calcium-dissolving circles were picked for further separation and purification. Gram-positive and catalase-negative colonies were selected for rescreening through Gram staining and catalase test to isolate and obtain plant lactobacillus.

[0048] 3. Identification of strain HP-ZW2 Physiological and biochemical identification: Referring to the "Classification and Identification of Lactic Acid Bacteria and Experimental Methods", the selected strain HP-ZW2 was cultured in MRS liquid culture medium at 37°C for 24 hours, inoculated into the corresponding bacterial micro-reaction tube with a bacterial loop, cultured at 37°C for 24 hours, and the color change of the reaction tube was recorded. Identification was performed according to the "Common Bacterial System Identification Manual". Table 1 shows the physiological and biochemical reaction results of strains STM1-3. Table 1 Physiological and biochemical reaction results of strain HP-ZW2

[0049] project result project result project result sucrose + Arabinose - D-Fructose + Glucose Acid Candy - Cellobiose + maltose + lactose + Songsantang + Xylose + Mannitol + Galactose + Escin + Mannose + Sorbitol - glucose +

[0050] Identification results: strain HP-ZW2 is a Gram-positive bacillus, and was preliminarily identified as Lactobacillus plantarum based on physiological and biochemical reaction results.

[0051] Application Examples

[0052] Application Example 1

[0053] A shrimp feed, comprising the following raw materials by weight: 28 kg of fish meal, 1 kg of multivitamins, 2 kg of soybean lecithin powder, 18 kg of fermented material, 4 kg of pineapple extract, 1 kg of calcium dihydrogen phosphate, and 2 kg of sucrose;

[0054] The raw materials of the fermentation product include Elodea, lotus root powder, protein powder and Lactobacillus plantarum HP-ZW2.

[0055] The method for preparing a fermented product comprises the following steps:

[0056] S1, grinding 20 kg of Elodea, lotus root powder and protein powder respectively, and then mixing to obtain a mixture;

[0057] S2, disperse the mixture in 20L of water, and inoculate at a rate of 3×10 7 cfu / L was added into Lactobacillus plantarum HP-ZW2 and fermented at 36°C for 24h to obtain a fermentation product.

[0058] The mass ratio of Elodea, lotus root powder and protein powder is 1:0.4:0.2.

[0059] Pineapple Extract Xi'an Prius Bioengineering Co., Ltd.

[0060] Application Example 2

[0061] A shrimp feed, which is different from the application example 1 in that it includes the following raw materials by weight: 33 kg of fish meal, 3 kg of multivitamins, 5 kg of soybean lecithin powder, 22 kg of fermented material, 8 kg of pineapple extract, 2 kg of monocalcium phosphate, and 4 kg of sucrose;

[0062] The method for preparing a fermented product comprises the following steps:

[0063] S1, grinding 24 kg of Elodea, lotus root powder and protein powder respectively, and then mixing to obtain a mixture;

[0064] S2, disperse the mixture in 35L of water, inoculate at a rate of 6×10 7 cfu / L was added into Lactobacillus plantarum HP-ZW2 and fermented at 38°C for 26h to obtain a fermentation product.

[0065] The mass ratio of Elodea, lotus root powder and protein powder is 1:0.6:0.3.

[0066] Application Example 3

[0067] A shrimp feed, which is different from Application Example 1 in that the mass ratio of fish meal, fermentation product and pineapple extract is 4:5:1.

[0068] Application Example 4

[0069] A shrimp feed, which is different from Application Example 1 in that the mass ratio of fish meal, fermentation product and pineapple extract is 7:3:1.

[0070] Application Example 5

[0071] A shrimp feed, which is different from Application Example 1 in that the mass ratio of Elodea, lotus root powder and protein powder is 1:0.9:0.1.

[0072] Application Example 6

[0073] A shrimp feed, which is different from Application Example 1 in that a method for preparing a pineapple extract comprises the following steps:

[0074] (1) 15 kg of pineapple was peeled, washed, crushed, and filtered to obtain juice, which was dispersed in 18 L of deionized water, and 0.3 kg of ginger juice and 0.1 kg of pectinase were added for enzymolysis at a temperature of 45° C. for 4 h. After the enzymolysis was completed, the enzyme was inactivated at 90° C. for 30 min, and the extract was filtered to obtain the extract;

[0075] (2) The extract was dispersed in 20 L of acetic acid solution with a mass fraction of 20%, stirred at 76° C. for 2 h, chitosan and modified shell powder were added, stirred for 3 h, dried and ground to obtain pineapple extract.

[0076] The mass ratio of the extract, chitosan and modified shell powder is 1:0.3:0.4.

[0077] The preparation method of modified shell powder includes the following steps: dispersing 10 kg of shell powder in 15 L of 10% sodium hydroxide solution by mass, stirring for 1.5 hours, washing with water, drying, and then dispersing in 12 L of deionized water, adding xanthan gum and astragalus powder, stirring at a temperature of 85°C for 2 hours, and drying to obtain modified shell powder.

[0078] The mass ratio of shell powder, xanthan gum and astragalus powder is 1:0.05:0.2.

[0079] Application Example 7

[0080] A shrimp feed, which is different from Application Example 6 in that chitosan is not added.

[0081] Application Example 8

[0082] A shrimp feed, which is different from Application Example 6 in that modified shell powder is not added.

[0083] Application Example 9

[0084] A shrimp feed, which is different from Application Example 6 in that the mass ratio of the extract, chitosan and modified shell powder is 1:0.5:0.6.

[0085] Application Example 10

[0086] A shrimp feed, which is different from Application Example 6 in that the mass ratio of the extract, chitosan and modified shell powder is 1:0.8:0.1.

[0087] Application Example 11

[0088] A shrimp feed, which is different from Application Example 6 in that xanthan gum is not added in the preparation method of the modified shell powder.

[0089] Application Example 12

[0090] A shrimp feed, which is different from Application Example 6 in that no astragalus powder is added in the preparation method of the modified shell powder.

[0091] Application Example 13

[0092] A shrimp feed, which is different from Application Example 6 in that the mass ratio of shell powder, xanthan gum and astragalus powder is 1:0.07:0.1.

[0093] Application Example 14

[0094] A shrimp feed, which is different from Application Example 6 in that the mass ratio of shell powder, xanthan gum and astragalus powder is 1:0.2:0.05.

[0095] Application Comparative Example 1

[0096] A shrimp feed, which is different from Application Example 1 in that no fermentation product is added.

[0097] Application Comparative Example 2

[0098] A shrimp feed, which is different from Application Example 1 in that pineapple extract is not added.

[0099] Performance test experiment

[0100] 40-day feeding experiment of crayfish

[0101] Location: Yueyang crayfish breeding base Experimental method: Use crayfish seedlings from the same batch, release them on the same day, mix and feed them with the shrimp feed prepared in this application, mix and feed them twice a day in the morning and evening, and collect dead shrimps from the bottom sewage pipe net every day and count them.

[0102] The average salinity of the aquaculture water is 1.0 / 1000 and the average water temperature is 28.2℃.

[0103] Table 2 Various test results of crayfish

[0104]

[0105]

[0106] The shrimp feed prepared in Application Examples 1-2, Application Examples 5, Application Examples 9, and Application Examples 13 of the present application, the fermented product adopts the preparation method of the present application, the pineapple extract is commercially available, and the shrimp farming test is carried out. As can be seen from Table 2, in Application Example 1, the average unit weight in 20 days is 37g, the average unit weight in 38 days is 50g, and the mortality rate is 4%, indicating that the fermented product of the present application provides a variety of nutrients required for shrimp growth, including protein, amino acids, vitamins and minerals. The beneficial bacteria and enzymes produced in the fermentation process can improve the intestinal microecology of shrimp, promote intestinal health, improve the digestion and absorption rate of feed, and promote the growth and development of shrimp.

[0107] In Application Example 3-4, the mass ratio of fish meal, fermentation product and pineapple extract was further changed. As can be seen from Table 2, compared with Application Example 1-2, the average unit weight in 20 days was 39 g, the average unit weight in 38 days was 53 g, and the mortality rate was 3%, indicating that fish meal is rich in high-quality protein and fatty acids, and the fermentation product has a high nutritional value, improves the digestion and absorption of shrimps, optimizes the intestinal microecology, and helps shrimps absorb and eat fish meal. The pineapple extract not only provides the fiber required for shrimp growth, but also promotes shrimp digestion and helps to eat more. The combination of fish meal, fermentation product and pineapple extract helps shrimps eat and promotes the growth of shrimps.

[0108] The pineapple extract in Application Example 6 is self-made. As shown in Table 2, compared with Application Examples 1-2, the average unit weight is 45g in 20 days, the average unit weight is 60g in 38 days, and the mortality rate is 1%, indicating that the components in the pineapple extract cooperate with each other, chitosan inhibits the growth of various bacteria and fungi, has antioxidant capacity, protects the active ingredients in the pineapple extract from oxidative damage, and prolongs its shelf life. The modified shell powder is used as a supplementary source of calcium to improve the nutritional value of the pineapple extract, which helps to subsequently increase the calcium content of the shrimp feed. The prepared pineapple extract has high antibacterial properties and nutritional value, which helps to subsequently improve the corresponding properties of the shrimp feed.

[0109] In the preparation method of pineapple extract in Application Example 7, chitosan is not added. As can be seen from Table 2, compared with Application Example 6, the average unit weight in 20 days is 42g, the average unit weight in 38 days is 55g, and the mortality rate is 2%, indicating that chitosan has natural antibacterial properties, can inhibit the growth of various bacteria and fungi, has antioxidant capacity, can scavenge free radicals, and subsequently improve the antibacterial activity of shrimp feed, enhance immune function, promote intestinal health, and improve growth performance.

[0110] In the preparation method of pineapple extract in Application Example 8, modified shell powder is not added. As can be seen from Table 2, compared with Application Example 6, the average unit weight at 20 days is 41 g, the average unit weight at 38 days is 54 g, and the mortality rate is 2%, indicating that the modified shell powder is rich in calcium and can be used as a supplementary source of calcium to improve the nutritional value of pineapple extract, which is helpful to subsequently increase the calcium content of shrimp feed and subsequently improve the corresponding performance of shrimp feed.

[0111] Application Example 10 changes the mass ratio of the extract, chitosan and modified shell powder. As can be seen from Table 2, compared with Application Example 6, the average single weight after 20 days is 43g, the average single weight after 38 days is 56g, and the mortality rate is 2%, indicating that the extract is closely connected with the modified shell powder, which helps to improve the comprehensive nutritional value of the extract. The modified shell powder is rich in calcium and can be used as a supplementary source of calcium. The combination of extract, chitosan and modified shell powder has high antibacterial properties and nutritional value, which helps to subsequently improve the corresponding performance of shrimp feed.

[0112] In the preparation method of modified shell powder in Application Example 11, xanthan gum is not added. As can be seen from Table 2, compared with Application Example 6, the average single weight in 20 days is 44g, the average single weight in 38 days is 57g, and the mortality rate is 2%, indicating that xanthan gum has a certain viscosity, so that the astragalus powder can be stably loaded on the surface of the shell powder, thereby improving the nutritional value and antibacterial activity of the shell powder. Moreover, the antibacterial activity of the shell powder combined with the stability of xanthan gum may enhance the anti-corrosion ability of the system and extend the shelf life of the product.

[0113] In the preparation method of modified shell powder in Application Example 12, astragalus powder is not added. As can be seen from Table 2, compared with Application Example 6, the average unit weight at 20 days is 43g, the average unit weight at 38 days is 56g, and the mortality rate is 2%, indicating that astragalus powder is rich in various nutrients, such as flavonoids, polysaccharides, amino acids, etc., which combined with the calcium in shell powder can provide a more comprehensive nutritional supplement, help supplement the nutrients needed by shrimp, and have antibacterial and preservative properties.

[0114] Application Example 14 changes the mass ratio of shell powder, xanthan gum and astragalus powder. As can be seen from Table 2, compared with Application Example 6, the average single weight in 20 days is 44g, the average single weight in 38 days is 58g, and the mortality rate is 2%, indicating that shell powder is rich in calcium. Astragalus powder is rich in various nutrients, such as flavonoids, polysaccharides, amino acids, etc., which can provide more comprehensive nutritional supplements when combined with the calcium in shell powder. Xanthan gum has a certain viscosity, which makes the astragalus powder stably loaded on the surface of shell powder, thereby improving the nutritional value and antibacterial activity of shell powder. The combination of the three improves the nutritional value and antibacterial activity of the mixture.

[0115] In the comparative example 1, no fermentation product is added. As can be seen from Table 2, compared with the application example 6, the average unit weight after 20 days is 27 g, the average unit weight after 38 days is 40 g, and the mortality rate is 9%, indicating that the plant lactobacillus HP-ZW2 can grow and reproduce rapidly in the fermentation matrix, start the fermentation process, and ensure the smooth progress of the fermentation. The prepared fermentation product provides a variety of nutrients required for the growth of shrimps, promotes intestinal health, improves the digestion and absorption rate of feed, can promote the growth and development of shrimps, enhance the immunity of shrimps, and improve the water quality of aquaculture water, thereby increasing the growth rate of shrimps.

[0116] In Comparative Example 2, no pineapple extract was added. As can be seen from Table 2, compared with Application Example 6, the average unit weight after 20 days was 30 g, the average unit weight after 38 days was 43 g, and the mortality rate was 7%, indicating that the pineapple extract prepared in the present application has high antibacterial properties and nutritional value, which is helpful to subsequently improve the corresponding performance of shrimp feed and promote the growth of shrimp.

[0117] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make modifications to the present embodiment without any creative contribution as needed, but such modifications are protected by the patent law as long as they are within the scope of the claims of the present application.

Claims

1. An application of Lactobacillus plantarum HP-ZW2 in preparing shrimp feed, characterized in that: The strain is deposited in China Center for Type Culture Collection, the depository address is Wuhan University, Wuhan, China, the deposit number is CCTCCNO: M20221790, and the deposit date is November 14, 2022; The shrimp feed comprises the following raw materials in parts by weight: 28-33 parts of fish meal, 1-3 parts of multivitamins, 2-5 parts of soybean lecithin powder, 18-22 parts of fermented material, 4-8 parts of pineapple extract, 1-2 parts of calcium dihydrogen phosphate, and 2-4 parts of sucrose; The raw materials of the fermented product include Elodea, lotus root powder, protein powder and the plant lactobacillus HP-ZW2.

2. The use according to claim 1, characterized in that: The mass ratio of the fish meal, the fermented product and the pineapple extract is 4-7:3-5:

1.

3. The use according to claim 1, characterized in that: The method for preparing the fermented product comprises the following steps: S1, grinding Elodea, lotus root powder and protein powder separately, and then mixing to obtain a mixture; S2, disperse the mixture in water, according to the inoculation amount of 3×10 7 -6×10 7 cfu / L was added into Lactobacillus plantarum HP-ZW2 and fermented at 36-38°C for 24-26h to obtain a fermentation product.

4. The use according to claim 3, characterized in that: The mass ratio of the elodea, lotus root powder and protein powder is 1:0.4-0.6:0.2-0.

3.

5. The use according to claim 1, characterized in that: The preparation method of the pineapple extract comprises the following steps: (1) Peeling, washing, crushing and filtering the pineapple to obtain juice, dispersing the juice in deionized water, adding ginger juice and pectinase for enzymolysis at a temperature of 40-45° C. for 3-4 h. After the enzymolysis is completed, inactivating the enzyme, filtering and obtaining an extract; (2) Dispersing the extract in acetic acid solution, stirring at 70-80°C for 1-2 hours, adding chitosan and modified shell powder, stirring for 2-3 hours, drying and grinding to obtain pineapple extract.

6. The use according to claim 5, characterized in that: The mass ratio of the extract, chitosan and modified shell powder is 1:0.3-0.5:0.4-0.

6.

7. The use according to claim 5, characterized in that: The preparation method of the modified shell powder comprises the following steps: dispersing the shell powder in a sodium hydroxide solution, stirring for 1-2 hours, washing with water, drying, and then dispersing in deionized water, adding xanthan gum and astragalus powder, stirring at a temperature of 80-85° C. for 1-2 hours, and drying to obtain the modified shell powder.

8. The use according to claim 7, characterized in that: The mass ratio of the shell powder, xanthan gum and astragalus powder is 1:0.05-0.07:0.1-0.2.

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