Saline-alkali water fish compound feed based on curcumin-lactic acid bacteria and preparation method thereof

Abstract

The invention discloses a compound feed for fishes in saline-alkaline water based on curcumin-lactic acid bacteria and a preparation method of the compound feed, and belongs to the technical field of aquaculture. The compound feed is prepared from curcumin microcapsules, a lactic acid bacteria complex microbial inoculant, fructo-oligosaccharide and a basal feed. The preparation method comprises the following steps: embedding sodium alginate to prepare curcumin microcapsules; preparing a lactic acid bacteria complex microbial inoculant; and mixing the curcumin microcapsule, the lactic acid bacteria complex microbial inoculant, the fructo-oligosaccharide and the basal feed. According to the saline-alkaline water fish compound feed based on curcumin-lactic acid bacteria, a sodium alginate embedding technology is adopted in the preparation process, and the stability and bioavailability of curcumin are improved; fructo-oligosaccharide is added to serve as prebiotics, and the synergistic interaction of lactic acid bacteria colonization and curcumin is promoted. The feed additive has the effects of oxidation resistance synergy, intestinal barrier repair, flora regulation and control and efficient relieving of saline-alkali stress. The cost is low and safe, and the production cost is reduced by 30% compared with that of a traditional scheme. The feed is suitable for livestock and aquatic feed, and is especially suitable for saline-alkali soil centralized culture areas.

Description

Technical Field

[0001] The present invention belongs to the technical field of aquaculture; specifically, it relates to a compound feed for saline-alkali water fish based on curcumin-lactic acid bacteria and a preparation method thereof. Background Art

[0002] Carbonate-type saline-alkali water is one of the main challenges in inland saline-alkali aquaculture. Among them, the high alkalinity directly harms the physiological functions of aquatic organisms. The high Na + , K + / HCO 3 - ratio imbalance forces fish to consume a large amount of energy for ion regulation, resulting in growth retardation and reduced feed conversion rate; the high pH environment inhibits the digestive enzyme activities in the gills and intestines of fish, interferes with nutrient absorption, and increases the toxicity of ammonia nitrogen (NH 3 ), causing hepatopancreas damage; under high-alkali stress, reactive oxygen species (ROS) accumulate in fish bodies, causing tissue oxidative damage (such as apoptosis of gill filament cells), while reducing the activities of lysozyme and complement and increasing the risk of pathogen infection. Existing technologies mostly rely on chemical growth promoters (such as hormones, antibiotics), which have problems of ecological pollution and drug residues.

[0003] In view of the above problems, functional feed additives show important application values. For example, antioxidants (curcumin, vitamin E): scavenge free radicals and protect organs such as gills and livers from oxidative damage; intestinal health regulators (probiotics, organic acids): improve the intestinal microenvironment, enhance the activities of digestive enzymes and nutrient utilization rates; immune enhancers (β-glucan, chitosan oligosaccharide): activate the innate immune signaling pathway and enhance disease resistance. Research shows that compound additives can have synergistic effects, increasing the weight gain rate of farmed animals by 25% - 40%, reducing the feed coefficient by 15% - 20%, and significantly reducing the mortality rate at the same time. Curcumin has functions such as anti-inflammatory, antioxidant, and regulation of lipid metabolism, but its application in saline-alkali water fish has not been reported. Therefore, the use of curcumin and probiotic compound additives not only alleviates the saline-alkali water environmental stress but also promotes the sustainable development of fishery resources in saline-alkali land, with significant economic and ecological benefits. Currently, it is urgent to further optimize the formula to solve the problems of slow fish growth rate and low fry survival rate in saline-alkali water aquaculture, and then combine with precise feeding strategies to meet the aquaculture needs of diverse saline-alkali water qualities. Summary of the Invention

[0004] The purpose of the present invention is to provide a compound feed for saline-alkali water fish based on curcumin-lactic acid bacteria and a preparation method thereof to solve the problems of slow fish growth rate and low fry survival rate in existing saline-alkali water aquaculture.

[0005] A compound feed for saline-alkali water fish based on curcumin-lactic acid bacteria, which is made of 0.04% - 0.16% curcumin microcapsules, 0.1% - 0.5% lactic acid bacteria complex agent, 0.1% - 0.5% fructooligosaccharide (FOS) and the balance of basic feed by mass percentage.

[0006] Further, the basic feed is Tongwei expanded compound feed for fish.

[0007] The preparation method of the above-mentioned compound feed for saline-alkali water fish based on curcumin-lactic acid bacteria is realized according to the following steps:

[0008] I. Preparation of curcumin microcapsules:

[0009] Mix curcumin with absolute ethanol, then mix the obtained mixture with sodium alginate, then carry out embedding and freeze-drying, and then pass through an 80-mesh sieve to make microcapsules with a particle size ≤ 0.2 mm, which are curcumin microcapsules.

[0010] II. Lactic acid bacteria complex agent:

[0011] Expand and culture Lactobacillus plantarum L1 in a basic medium containing 10 - 15 mmol / L Na 2 HCO 3 until the viable count ≥ 1 × 10 9 CFU / g, after centrifugation, mix the thallus, sodium alginate and distilled water, and then carry out freeze-drying to obtain the lactic acid bacteria complex agent.

[0012] III. Compound:

[0013] Mix the above-mentioned curcumin microcapsules, lactic acid bacteria complex agent, fructooligosaccharide and basic feed, and then make granular or powdery feed, thus completing the preparation method.

[0014] Further, in step I, the curcumin and absolute ethanol are mixed at a volume ratio of 1:500, and the mixture and sodium alginate are mixed at a volume ratio of 50:1.

[0015] Further, Lactobacillus plantarum L1 in step II has been deposited in the China Center for Type Culture Collection, with the deposit number: CCTCC NO: M 20242780, the deposit time is December 10, 2024, and the deposit address is Wuhan University, Wuhan, China. It is Lactobacillus plantarum HRFRI-L1.

[0016] Further, the basic medium in step II is MRS medium.

[0017] Further, the conditions for the expansion culture in step II are: culture at 35 - 37 °C for 2 - 3 d.

[0018] Further, in step two, the centrifugation is carried out at 3000 rpm for 10 min.

[0019] Further, in step two, the bacterial cells, sodium alginate and distilled water are mixed at a volume ratio of 1:20:1000.

[0020] Further, in step three, the mass of the curcumin microcapsules accounts for 0.04% - 0.16% of the mass of the basal diet; the mass of the lactic acid bacteria complex bacterial agent accounts for 0.1% - 0.5% of the mass of the basal diet; the mass of the fructooligosaccharide accounts for 0.1% - 0.5% of the mass of the basal diet.

[0021] Further, in step three, the basal diet is Tongwei expanded compound fish feed.

[0022] Advantages of the present invention:

[0023] In the present invention, for the compound feed for saline-alkali water fish based on curcumin-lactic acid bacteria, the embedding technology is adopted in the preparation to improve the stability and bioavailability of curcumin; fructooligosaccharide is added as a prebiotic to promote the colonization of lactic acid bacteria and the synergistic effect of curcumin.

[0024] Antioxidant synergy: Curcumin scavenges free radicals, and lactic acid bacteria secrete superoxide dismutase (SOD), jointly reducing oxidative damage.

[0025] Intestinal barrier repair: Lactic acid bacteria regulate the intestinal osmotic pressure, and curcumin inhibits the NF-κB pathway, reducing intestinal inflammation.

[0026] Microflora regulation: Fructooligosaccharide promotes the proliferation of lactic acid bacteria and inhibits the colonization of harmful bacteria under saline-alkali stress.

[0027] Effectively alleviating saline-alkali stress: Through the synergistic effect of curcumin and lactic acid bacteria, the antioxidant capacity, intestinal barrier function and growth performance of animals are significantly improved.

[0028] Low cost and safe: Natural ingredients have no residue risk,

[0029] The dosage of curcumin is reduced, and the production cost is reduced by 30% compared with the traditional scheme.

[0030] Wide applicability: It can be adapted to livestock, poultry and aquatic feeds, especially suitable for concentrated aquaculture areas in saline-alkali land.

[0031] The present invention is applicable to the preparation of compound feed for saline-alkali water fish based on curcumin-lactic acid bacteria. Description of the drawings

[0032] Figure 1Effects of curcumin-lactic acid bacteria complex on antioxidant enzyme activities and MDA content in the liver of carp under high-alkali stress in the examples, where A: SOD enzyme activity in the liver; B: CAT enzyme activity in the liver; C: MDA content in the liver;

[0033] Figure 2 Effects of curcumin-lactic acid bacteria complex on the intestine of carp under high-alkali stress in the examples; where A: Microscopic structure of the control group; B: Microscopic structure of the high-alkali group; C: Microscopic structure of the curcumin-lactic acid bacteria complex plus alkali group. Specific implementation manners

[0034] The technical solution of the present invention is not limited to the specific implementation manners listed below, and also includes any combination between the specific implementation manners.

[0035] Specific implementation manner one: A saline-alkali water fish compound feed based on curcumin-lactic acid bacteria in this implementation manner is made of 0.04% - 0.16% curcumin microcapsules, 0.1% - 0.5% lactic acid bacteria complex agent, 0.1% - 0.5% fructooligosaccharide and the balance of basic feed by mass percentage.

[0036] Specific implementation manner two: The difference between this implementation manner and specific implementation manner one is that the basic feed is Tongwei fish-expanding compound feed. Other steps and parameters are the same as those in specific implementation manner one.

[0037] Specific implementation manner three: A preparation method of a saline-alkali water fish compound feed based on curcumin-lactic acid bacteria in this implementation manner is realized according to the following steps:

[0038] I. Preparation of curcumin microcapsules:

[0039] Mix curcumin with absolute ethanol, then mix the obtained mixture with sodium alginate, then carry out embedding and freeze-drying, and then pass through an 80-mesh sieve to make microcapsules with a particle size ≤ 0.2 mm, which are curcumin microcapsules;

[0040] II. Lactic acid bacteria complex agent:

[0041] Culture Lactobacillus plantarum L1 in a basic medium containing 10 - 15 mmol / L Na 2 HCO 3 for subculture until the viable count ≥ 1 × 10 9 CFU / g, after centrifugation, mix the bacterial cells, sodium alginate and distilled water, and then carry out freeze-drying to obtain the lactic acid bacteria complex agent;

[0042] III. Compound:

[0043] Mix the above-mentioned curcumin microcapsules, lactic acid bacteria complex agent, fructooligosaccharide, and basic feed, and then make granular or powdered feed, thus completing the preparation method.

[0044] In this embodiment, MRS medium, fructooligosaccharide, and basic feed are all commercially available products.

[0045] The compound feed for saline-alkali water fish based on curcumin-lactic acid bacteria prepared in this embodiment is stored at a low temperature of 4°C.

[0046] The compound feed for saline-alkali water fish based on curcumin-lactic acid bacteria prepared in this embodiment adopts a conventional feeding method and dosage.

[0047] Specific Embodiment 4: The difference between this embodiment and Specific Embodiment 3 is that in Step 1, the curcumin and absolute ethanol are mixed at a volume ratio of 1:500, and the mixture and sodium alginate are mixed at a volume ratio of 50:1. Other steps and parameters are the same as those in Specific Embodiment 3.

[0048] Specific Embodiment 5: The difference between this embodiment and Specific Embodiment 3 is that in Step 2, Lactobacillus plantarum L1 has been deposited in the China Center for Type Culture Collection, with the deposit number: CCTCC NO: M 20242780, the deposit time being December 10, 2024, and the deposit address being Wuhan University, Wuhan, China. It is Lactobacillus plantarum HRFRI-L1. Other steps and parameters are the same as those in Specific Embodiment 3.

[0049] Specific Embodiment 6: The difference between this embodiment and Specific Embodiment 3 is that in Step 2, the basic medium is MRS medium. Other steps and parameters are the same as those in Specific Embodiment 3.

[0050] Specific Embodiment 7: The difference between this embodiment and Specific Embodiment 3 is that in Step 2, the conditions for enlarged culture are: culture at 35 - 37°C for 2 - 3 days. Other steps and parameters are the same as those in Specific Embodiment 3.

[0051] Specific Embodiment 8: The difference between this embodiment and Specific Embodiment 3 is that in Step 2, the centrifugation is carried out at 3000 rpm for 10 min. Other steps and parameters are the same as those in Specific Embodiment 3.

[0052] Specific Embodiment 9: The difference between this embodiment and Specific Embodiment 3 is that in Step 2, the bacterial cells, sodium alginate, and distilled water are mixed at a volume ratio of 1:20:1000. Other steps and parameters are the same as those in Specific Embodiment 3.

[0053] Embodiment 10: The difference between this embodiment and Embodiment 3 is that in Step 3, the mass of the curcumin microcapsules accounts for 0.04% - 0.16% of the mass of the basic feed; the mass of the lactic acid bacteria complex bacterium agent accounts for 0.1% - 0.5% of the mass of the basic feed; the mass of the fructooligosaccharide accounts for 0.1% - 0.5% of the mass of the basic feed. Other steps and parameters are the same as those in Embodiment 3.

[0054] Embodiment 11: The difference between this embodiment and Embodiment 3 is that in Step 3, the basic feed is Tongwei fish puffed compound feed. Other steps and parameters are the same as those in Embodiment 3.

[0055] The beneficial effects of the present invention are verified through the following examples:

[0056] Example:

[0057] A preparation method of a saline-alkali water fish compound feed based on curcumin-lactic acid bacteria is realized according to the following steps:

[0058] I. Preparation of curcumin microcapsules:

[0059] Mix curcumin with absolute ethanol, then mix the obtained mixture with sodium alginate, then carry out embedding and freeze-drying, and then pass through an 80-mesh sieve to make microcapsules with a particle size ≤ 0.2 mm, which are curcumin microcapsules;

[0060] II. Lactic acid bacteria complex bacterium agent:

[0061] Expand and culture Lactobacillus plantarum L1 in a basic medium containing 15 mmol / L Na 2 HCO 3 until the viable bacteria count ≥ 1×10 9 CFU / g, after centrifugation, mix the bacterial cells, sodium alginate and distilled water, and then carry out freeze-drying to obtain the lactic acid bacteria complex bacterium agent;

[0062] III. Compound:

[0063] Mix the above-mentioned curcumin microcapsules, lactic acid bacteria complex bacterium agent, fructooligosaccharide and basic feed, and then make granular or powdery feed, thus completing the preparation method.

[0064] In Step I of this example, the curcumin and absolute ethanol are mixed at a volume ratio of 1:500, and the mixture and sodium alginate are mixed at a volume ratio of 50:1.

[0065] In step two of this example, Lactobacillus plantarum L1 has been deposited at the China Center for Type Culture Collection. The deposit number is: CCTCC NO: M 20242780. The deposit date is December 10, 2024, and the deposit address is Wuhan University, Wuhan, China. It is Lactobacillus plantarum HRFRI-L1.

[0066] The basal medium described in step two of this example is MRS medium.

[0067] The conditions for the enlarged culture described in step two of this example are: culturing at 37 °C for 3 days.

[0068] The centrifugation described in step two of this example: centrifuging at 3000 rpm for 10 min.

[0069] The bacterial cells, sodium alginate, and distilled water described in step two of this example are mixed at a volume ratio of 1:20:1000.

[0070] The mass of the curcumin microcapsules described in step three of this example accounts for 0.08% of the basal feed; the mass of the lactic acid bacteria complex agent accounts for 0.3% of the basal feed; the mass of fructooligosaccharide accounts for 0.1% - 0.5% of the basal feed.

[0071] The basal feed described in step three of this example is an extruded compound feed for fish, purchased from Tongwei Co., Ltd.

[0072] 180 common carps were divided into three groups (3 replicates in each group), a control group (basal feed), a high-alkali stress group (basal feed + 50 mmol / L alkaline water), and a high-alkali + curcumin-lactic acid bacteria complex agent group (i.e., the saline-alkali water fish compound feed based on curcumin-lactic acid bacteria prepared in this example + 50 mmol / L alkaline water). After feeding for 56 days, it was found that the saline-alkali water fish compound feed based on curcumin-lactic acid bacteria prepared in this example could improve the growth performance and the antioxidant capacity of the liver and intestine of common carps cultured in saline-alkali water. As shown in Table 1, alkali stress significantly reduced the final body weight of common carps. However, after feeding the curcumin-lactic acid bacteria complex agent, it could alleviate the high-alkali stress and improve the growth rate.

[0073]

[0074] Note: Different letters (a, b) represent significant differences, P < 0.05. n = 5.

[0075] The antioxidant enzyme activity of the common carp liver was tested, and the results are as Figure 1 shown. The saline-alkali water fish compound feed based on curcumin-lactic acid bacteria prepared in this example could enhance the antioxidant enzyme activity of the liver and resist the influence of high-alkali stress on the common carp liver.

[0076] The intestinal tissue samples of carp were subjected to HE staining, and the results are as Figure 2 shown. It was found that high-alkali stress led to the atrophy of intestinal villi and the thinning of the intestinal wall, damaging intestinal health. However, the curcumin-lactic acid bacteria compound could relieve intestinal damage and improve the survival rate.

[0077] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A curcumin-lactic acid bacteria-based saline-alkali water fish compound feed, characterized in that The invention is prepared from 0.04% to 0.16% of curcumin microcapsules, 0.1% to 0.5% of lactic acid bacteria compound agents, 0.1% to 0.5% of oligofructose and the remainder of basic feed according to mass percentage.

2. The method for preparing a compound feed for saline-alkali water fish based on curcumin-lactic acid bacteria according to claim 1, characterized in that The basic feed is an expanded compound feed for fish.

3. A method for preparing a curcumin-lactic acid bacteria-based saline-alkali water fish compound feed as claimed in claim 1, characterized in that It is implemented as follows:

1. Preparation of curcumin microcapsules: The curcumin is mixed with anhydrous ethanol, and the obtained mixture is mixed with sodium alginate, and then embedded and freeze-dried, and then passed through an 80-mesh sieve to prepare microcapsules with a particle size of ≤0.2 mm, namely, curcumin microcapsules; 2. Lactic acid bacteria compound agent: Lactobacillus plantarum L1 was cultured in a basic medium containing 10-15 mmol / L Na2HCO3 until the viable count was ≥1×10 9 CFU / g, and after centrifugation, the bacteria, sodium alginate and distilled water were mixed and then freeze-dried to prepare a lactic acid bacteria composite agent; 3. Compound: The preparation method is completed by mixing the curcumin microcapsules, the lactic acid bacteria compound agent, oligofructose and the basic feed, and then preparing the feed into granules or powders.

4. The method for preparing a compound feed for saline-alkali water fish based on curcumin-lactic acid bacteria according to claim 3, characterized in that The curcumin described in step 1 is mixed with anhydrous ethanol at a volume ratio of 1:500, and the mixture is mixed with sodium alginate at a volume ratio of 50:

1.

5. The method for preparing a compound feed for saline-alkali water fish based on curcumin-lactic acid bacteria according to claim 3, characterized in that The Lactobacillus plantarum L1 in step 2 has been deposited in the China Center for Type Culture Collection with a deposit number of CCTCC NO: M 20242780, a deposit date of December 10, 2024, and a deposit address of Wuhan University, Wuhan, China. It is Lactobacillus plantarum HRFRI-L1.

6. The method for preparing a compound feed for saline-alkali water fish based on curcumin-lactic acid bacteria according to claim 3, characterized in that The basic culture medium in step 2 is MRS culture medium.

7. The method for preparing a compound feed for saline-alkali water fish based on curcumin-lactic acid bacteria according to claim 3, characterized in that The conditions for the expanded culture in step 2 are: culture at 35-37° C. for 2-3 days.

8. The method for preparing a compound feed for saline-alkali water fish based on curcumin-lactic acid bacteria according to claim 3, characterized in that Centrifugation in step 2: 3000 rpm for 10 min.

9. The method for preparing a compound feed for saline-alkali water fish based on curcumin-lactic acid bacteria according to claim 3, characterized in that The bacteria, sodium alginate and distilled water described in step 2 are mixed in a volume ratio of 1:20:1000.

10. The method for preparing a compound feed for saline-alkali water fish based on curcumin-lactic acid bacteria according to claim 3, characterized in that The mass of the curcumin microcapsules described in step three accounts for 0.04% to 0.16% of the mass of the basic feed; the mass of the lactic acid bacteria compound agent accounts for 0.1% to 0.5% of the mass of the basic feed; and the mass of the oligofructose accounts for 0.1% to 0.5% of the mass of the basic feed.

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