Aquaculture nutritional agent and preparation method thereof

Abstract

The invention provides an aquaculture nutritional agent and a preparation method thereof, and belongs to the technical field of aquaculture. The invention provides an aquaculture nutritional agent. The aquaculture nutritional agent comprises calcium superphosphate, urea, sodium humate, a bacillus subtilis bacterial solution, a composite mineral agent and a nutritional supplement, the composite mineral agent comprises ferrous sulfate, zinc sulfate, manganese sulfate, copper sulfate and calcium carbonate; the nutritional supplement at least comprises lysine, methionine, vitamin C, a baicalein derivative and apigenin-7-glucoside. The aquaculture nutrient provided by the invention not only can improve the water quality and reduce the content of ammonia nitrogen in aquaculture water, but also can promote the growth performance of cultured animals and increase the weight gain rate of the cultured animals.

Description

Technical Field

[0001] The present invention relates to the technical field of aquaculture, and in particular to an aquaculture nutrient and a preparation method thereof. Background Art

[0002] Aquaculture systems are ecosystems subject to human intervention, and their primary productivity is primarily limited and regulated by key nutrients such as carbon (C), nitrogen (N), phosphorus (P), and potassium (K). Nutrient content in natural waters is generally low, often requiring external sources to meet the growth needs of aquatic organisms. When the biomass of aquaculture waters is maximized, the nutrients present in the water often fall short of demand, making appropriately increasing nutrient salt content crucial to aquaculture success. Nutrient deficiency in aquaculture waters leads to insufficient biomass of feed, chronic starvation of aquacultured animals, hindering growth and leading to nutrient deficiencies or even death. Excessive nutrient levels can lead to excessive feed intake, deteriorating water quality, and harmful effects on farmed animals. Therefore, the rational use of nutrients is crucial to achieving a balanced development between feed supply and the aquaculture ecosystem.

[0003] Traditional aquaculture nutrients are primarily based on animal excrement, plant residues, and various fermented organic matter. While their effects are long-lasting and mild, they contain a large number of pathogens, parasites, and other harmful substances, which can easily cause aquaculture diseases. Furthermore, these nutrients are complex, with slow decomposition of organic matter, high oxygen consumption, and a high level of residual material, which can easily cause water pollution. Therefore, there is an urgent need for aquaculture nutrients that can provide a sufficient food source for the growth and development of farmed animals while reducing water pollution and promoting the healthy circulation and development of aquaculture water ecosystems. Summary of the Invention

[0004] The present invention aims to provide an aquaculture nutrient and a preparation method thereof, which can not only improve water quality and reduce the ammonia nitrogen content in aquaculture water, but also promote the growth of aquaculture animals and increase their weight gain rate.

[0005] The technical solutions adopted by the present invention to achieve the above-mentioned purpose are: An aquaculture nutrient agent comprises superphosphate, urea, sodium humate, Bacillus subtilis liquid, a composite mineral agent and a nutritional supplement; the composite mineral agent comprises ferrous sulfate, zinc sulfate, manganese sulfate, copper sulfate and calcium carbonate; the nutritional supplement comprises at least lysine, methionine, vitamin C, a baicalein derivative and apigenin-7-glucoside; the baicalein derivative has a flavonoid group and a pyridine group.

[0006] The aquaculture nutrient provided by the present invention includes probiotics and nutrients. The nutrients can provide the nutrients required for the reproduction of the probiotics, allowing the probiotics to multiply in large quantities, helping to degrade harmful substances such as ammonia nitrogen in the water, improving water quality, and reducing toxic effects on aquatic animals. In addition, the nutrients used in the present invention can provide the nutrients required for the growth of plankton in the water, increase the biomass of the basic bait required for farmed animals, and improve the weight gain rate of farmed animals. The present invention uses baicalein derivatives and apigenin-7-glucoside in the aquaculture nutrient, which helps to increase the primary productivity of the water body, enhance the degradation effect of harmful substances such as ammonia nitrogen, improve the ecological environment of the water body, promote the healthy growth of farmed animals, and increase the weight gain rate of farmed animals.

[0007] Preferably, in the preparation of the baicalein derivative, baicalein is reacted with cis-2-methylcyclopropanecarboxylic acid in the presence of 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride and 4-dimethylaminopyridine to obtain the baicalein derivative.

[0008] More preferably, the molar ratio of baicalein to cis-2-methylcyclopropanecarboxylic acid is 1:0.5-2.

[0009] More preferably, the molar ratio of baicalein to 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride is 1:1-3.

[0010] More preferably, the molar ratio of baicalein to 4-dimethylaminopyridine is 1:0.2-1.

[0011] Preferably, the mass ratio of superphosphate to urea is 1:0.5-1.

[0012] Preferably, the mass ratio of sodium humate to calcium superphosphate is 1:4-16.

[0013] Preferably, the usage ratio of Bacillus subtilis liquid and sodium humate is 1 μL:30-120 g.

[0014] Preferably, the mass ratio of the composite mineral agent to sodium humate is 1:3-12.

[0015] Preferably, the mass ratio of the nutritional supplement to sodium humate is 1:10-40.

[0016] Preferably, the preparation of baicalein derivatives is specifically as follows: Baicalein and cis-2-methylcyclopropanecarboxylic acid are dissolved in methanol, 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride and 4-dimethylaminopyridine are added, and the mixture is reacted for 8-16 hours under a nitrogen atmosphere. After the reaction, dichloromethane is used for extraction 3-5 times. The organic layer is retained and washed with a saturated sodium chloride solution until the pH is neutral, filtered, and dried to obtain a baicalein derivative.

[0017] More preferably, the molar ratio of baicalein to cis-2-methylcyclopropanecarboxylic acid is 1:0.5-2.

[0018] More preferably, the usage ratio of baicalein and methanol is 1 mmol:10-20 mL.

[0019] More preferably, the molar ratio of baicalein to 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride is 1:1-3.

[0020] More preferably, the molar ratio of baicalein to 4-dimethylaminopyridine is 1:0.2-1.

[0021] More preferably, the volume ratio of methanol to dichloromethane is 1:1-2.

[0022] Preferably, the aquaculture nutrient includes superphosphate, urea, sodium humate, Bacillus subtilis liquid, complex mineral agent, and nutritional supplement.

[0023] More preferably, the mass ratio of superphosphate to urea is 1:0.5-1.

[0024] More preferably, the mass ratio of sodium humate to calcium superphosphate is 1:4-16.

[0025] More preferably, the usage ratio of Bacillus subtilis liquid and sodium humate is 1 μL:30-120 g.

[0026] More preferably, the mass ratio of the composite mineral agent to sodium humate is 1:3-12.

[0027] More preferably, the mass ratio of the nutritional supplement to sodium humate is 1:10-40.

[0028] More preferably, the complex mineral agent includes ferrous sulfate, zinc sulfate, manganese sulfate, copper sulfate and calcium carbonate.

[0029] More preferably, the mass ratio of ferrous sulfate to zinc sulfate is 1:1-2.

[0030] More preferably, the mass ratio of ferrous sulfate to manganese sulfate is 1:0.1-0.4.

[0031] More preferably, the mass ratio of ferrous sulfate to copper sulfate is 1:0.2-1.

[0032] More preferably, the mass ratio of ferrous sulfate to calcium carbonate is 1:3-15.

[0033] More preferably, the nutritional supplement includes lysine, methionine, vitamin C, and at least one of a baicalein derivative, apigenin-7-glucoside, and dihydroquercetin. The present invention further incorporates dihydroquercetin into the nutritional supplement to increase the beneficial ingredients in the aquaculture nutrient, thereby further promoting the growth of plankton in the water and increasing primary productivity in the water, thereby further improving the degradation efficiency of harmful substances such as ammonia nitrogen in the water and promoting the growth of farmed animals.

[0034] More preferably, the mass ratio of lysine to methionine is 1:1-2.

[0035] More preferably, the mass ratio of lysine to vitamin C is 1:1-2.

[0036] More preferably, the mass ratio of lysine to baicalein derivative is 1:0.3-0.5.

[0037] More preferably, the mass ratio of lysine to apigenin-7-glucoside is 1:0.1-0.3.

[0038] More preferably, the mass ratio of lysine to dihydroquercetin is 1:0.1-0.2.

[0039] The present invention uses superphosphate, urea, sodium humate, Bacillus subtilis liquid, composite mineral agent and nutritional supplement to form an aquaculture nutrient agent, wherein the composite mineral agent includes ferrous sulfate, zinc sulfate, manganese sulfate, copper sulfate and calcium carbonate; the nutritional supplement includes lysine, methionine, vitamin C, baicalein derivatives, apigenin-7-glucoside and dihydroquercetin, thereby having the following beneficial effects: the aquaculture nutrient provided by the present invention can not only promote the reproduction of Bacillus subtilis, improve water quality, and facilitate the absorption and utilization of harmful substances such as ammonia nitrogen in the water body, reducing the ammonia nitrogen content in the aquaculture water to 0.148-0.243 mg / L; but also can promote the growth of plankton in the water body, increase the biomass in the water body, and improve the weight gain rate of aquaculture animals, with the weight gain rate being 188.4-229.7%. Therefore, the present invention provides an aquaculture nutrient agent with excellent water quality improvement performance and excellent growth promotion performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 It is the ammonia nitrogen content in the aquaculture water. DETAILED DESCRIPTION

[0041] The present invention will be further described in detail below in conjunction with specific embodiments. The examples provided are only for illustrating the present invention and are not intended to limit the scope of the present invention. The examples provided below can serve as a guide for further improvements by those skilled in the art and are not intended to limit the present invention in any way.

[0042] The experimental methods in the following examples are conventional methods unless otherwise specified. The materials and reagents used in the following examples are commercially available unless otherwise specified.

[0043] Example 1: Aquaculture nutrients, including, Superphosphate, urea, sodium humate, Bacillus subtilis culture fluid, complex mineral agents, and nutritional supplements. The mass ratio of superphosphate to urea is 1:0.86; the mass ratio of sodium humate to superphosphate is 1:8; the dosage ratio of Bacillus subtilis culture fluid to sodium humate is 1 μL:60g (Bacillus subtilis culture fluid was purchased from Shanghai Biyuntian Biotechnology Co., Ltd.); the mass ratio of complex mineral agents to sodium humate is 1:6; the mass ratio of nutritional supplements to sodium humate is 1:20. The complex mineral agents include ferrous sulfate, zinc sulfate, manganese sulfate, copper sulfate, and calcium carbonate. The mass ratio of ferrous sulfate to zinc sulfate is 1:1, the mass ratio of ferrous sulfate to manganese sulfate is 1:0.2, the mass ratio of ferrous sulfate to copper sulfate is 1:0.5, and the mass ratio of ferrous sulfate to calcium carbonate is 1:7. The nutritional supplement includes lysine, methionine and vitamin C, the mass ratio of lysine to methionine is 1:1, and the mass ratio of lysine to vitamin C is 1:1.

[0044] Example 2: Preparation of baicalein derivatives, comprising: Baicalein and cis-2-methylcyclopropanecarboxylic acid were dissolved in methanol, and 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride and 4-dimethylaminopyridine were added. The mixture was reacted under a nitrogen atmosphere for 12 hours. After completion of the reaction, the mixture was extracted three times with dichloromethane. The organic layer was retained, washed with saturated sodium chloride solution until the pH was neutral, filtered, and dried to obtain a baicalein derivative. The molar ratio of baicalein to cis-2-methylcyclopropanecarboxylic acid was 1:1.2, the amount of baicalein to methanol was 1 mmol:10 mL, the molar ratio of baicalein to 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride was 1:1.5, the molar ratio of baicalein to 4-dimethylaminopyridine was 1:0.5, and the volume ratio of methanol to dichloromethane was 1:1.

[0045] Aquaculture nutrients, including, Superphosphate, urea, sodium humate, Bacillus subtilis culture fluid, complex mineral agents, and nutritional supplements. The mass ratio of superphosphate to urea is 1:0.86; the mass ratio of sodium humate to superphosphate is 1:8; the dosage ratio of Bacillus subtilis culture fluid to sodium humate is 1 μL:60g (Bacillus subtilis culture fluid was purchased from Shanghai Biyuntian Biotechnology Co., Ltd.); the mass ratio of complex mineral agents to sodium humate is 1:6; the mass ratio of nutritional supplements to sodium humate is 1:20. The complex mineral agents include ferrous sulfate, zinc sulfate, manganese sulfate, copper sulfate, and calcium carbonate. The mass ratio of ferrous sulfate to zinc sulfate is 1:1, the mass ratio of ferrous sulfate to manganese sulfate is 1:0.2, the mass ratio of ferrous sulfate to copper sulfate is 1:0.5, and the mass ratio of ferrous sulfate to calcium carbonate is 1:7. The nutritional supplement includes lysine, methionine, vitamin C, baicalein derivatives and apigenin-7-glucoside. The mass ratio of lysine to methionine is 1:1, the mass ratio of lysine to vitamin C is 1:1, the mass ratio of lysine to baicalein derivatives is 1:0.5, and the mass ratio of lysine to apigenin-7-glucoside is 1:0.3.

[0046] Example 3: The preparation of baicalein derivatives is the same as in Example 2.

[0047] Compared with Example 2, the aquaculture nutrient supplement is the same as Example 2 except that the mass ratio of lysine to the baicalein derivative in the nutrient supplement is changed to 1:0.3.

[0048] Example 4: The preparation of baicalein derivatives is the same as in Example 2.

[0049] Compared with Example 2, the aquaculture nutrient is the same as Example 2 except that the mass ratio of lysine to apigenin-7-glucoside in the nutrient supplement is changed to 1:0.1. Other conditions are the same as those in Example 2.

[0050] Example 5: The preparation of baicalein derivatives is the same as in Example 2.

[0051] Aquaculture nutrients, including, Superphosphate, urea, sodium humate, Bacillus subtilis culture fluid, complex mineral agents, and nutritional supplements. The mass ratio of superphosphate to urea is 1:0.86; the mass ratio of sodium humate to superphosphate is 1:8; the dosage ratio of Bacillus subtilis culture fluid to sodium humate is 1 μL:60g (Bacillus subtilis culture fluid was purchased from Shanghai Biyuntian Biotechnology Co., Ltd.); the mass ratio of complex mineral agents to sodium humate is 1:6; the mass ratio of nutritional supplements to sodium humate is 1:20. The complex mineral agents include ferrous sulfate, zinc sulfate, manganese sulfate, copper sulfate, and calcium carbonate. The mass ratio of ferrous sulfate to zinc sulfate is 1:1, the mass ratio of ferrous sulfate to manganese sulfate is 1:0.2, the mass ratio of ferrous sulfate to copper sulfate is 1:0.5, and the mass ratio of ferrous sulfate to calcium carbonate is 1:7. The nutritional supplements include lysine, methionine, vitamin C, baicalein derivatives, apigenin-7-glucoside and dihydroquercetin. The mass ratio of lysine to methionine is 1:1, the mass ratio of lysine to vitamin C is 1:1, the mass ratio of lysine to baicalein derivatives is 1:0.5, the mass ratio of lysine to apigenin-7-glucoside is 1:0.3, and the mass ratio of lysine to dihydroquercetin is 1:0.2.

[0052] Example 6: The preparation of baicalein derivatives is the same as in Example 2.

[0053] Compared with Example 5, the aquaculture nutrient is the same as Example 5 except that the mass ratio of lysine to dihydroquercetin in the nutritional supplement is changed to 1:0.1.

[0054] Comparative Example 1: The aquaculture nutrient, compared with Example 2, is the same as Example 2 except that the baicalein derivative is not added.

[0055] Comparative Example 2: The preparation of baicalein derivatives is the same as in Example 2.

[0056] Compared with Example 2, the aquaculture nutrient is the same as Example 2 except that apigenin-7-glucoside is not added.

[0057] Comparative Example 3: The aquaculture nutrient, compared with Example 5, is the same as Example 5 except that the baicalein derivative and apigenin-7-glucoside are not added. Other conditions are the same as Example 5.

[0058] Experimental example: 1. Ammonia nitrogen content detection For 9 aquaculture ponds (bottom area of ​​4.5m 2 , with a volume of 5.4m 3) to clean and remove the silt deposited at the bottom of the aquaculture pond, and then add potassium permanganate to the aquaculture pond for soaking and disinfection. The ratio of potassium permanganate usage to the volume of the aquaculture pond is 1g:0.05m 3 After cleaning, the nine aquaculture ponds were filled with water to a depth of 1m. The nine aquaculture ponds were numbered 1-9 and treated with the aquaculture nutrients of Examples 1-6 and Comparative Examples 1-3 for 7 days. The volume ratio of the aquaculture nutrients to the water in the aquaculture ponds was 1g:4m 3 After the treatment, water samples with a depth of about 0.5 m were collected from four randomly selected sampling points in the aquaculture pond, and the ammonia nitrogen content in the water samples was determined by Nessler's reagent spectrophotometry.

[0059] Figure 1 The ammonia nitrogen content in the aquaculture water. Figure 1 It can be seen that the aquaculture nutrient agent of Example 2-4 is better than that of Example 1 in reducing the ammonia nitrogen content in the water sample because, in the aquaculture nutrient agent, baicalein derivatives and apigenin-7-glucoside are additionally added to the aquaculture nutrient agent, while Example 1 does not add baicalein derivatives and apigenin-7-glucoside; the aquaculture nutrient agent of Example 2-4 is better than that of Comparative Example 1 and Comparative Example 2 in reducing the ammonia nitrogen content in the water sample because, in the aquaculture nutrient agent, Comparative Example 1 only additionally adds apigenin-7-glucoside, while Comparative Example 2 only additionally adds baicalein derivatives; the aquaculture nutrient agent of Example 2 is better than that of Example 3 and Example 4 in reducing the ammonia nitrogen content in the water sample because, in the aquaculture nutrient agent, the amounts of baicalein derivatives and apigenin-7-glucoside used are different. This shows that the introduction of baicalein derivatives and apigenin-7-glucoside into aquaculture nutrients can effectively reduce the ammonia nitrogen content in water, and compared with the use of baicalein derivatives and apigenin-7-glucoside alone, the synergistic use of baicalein derivatives and apigenin-7-glucoside makes the aquaculture nutrient provided by the present invention more effective in reducing the ammonia nitrogen content in water samples.

[0060] The aquaculture nutrient of Examples 5-6 is superior to that of Example 2 in reducing the ammonia nitrogen content in the water sample because baicalein derivatives, apigenin-7-glucoside, and dihydroquercetin are additionally added to the aquaculture nutrient, while Example 2 only additionally adds baicalein derivatives and apigenin-7-glucoside; the aquaculture nutrient of Examples 5-6 is superior to that of Comparative Example 3 in reducing the ammonia nitrogen content in the water sample because baicalein derivatives and apigenin-7-glucoside are not added to the aquaculture nutrient. The aquaculture nutrient of Example 5 is superior to that of Example 6 in reducing the ammonia nitrogen content in the water sample because the amount of dihydroquercetin used in the aquaculture nutrient is different. This shows that the further addition of dihydroquercetin to the aquaculture nutrient of the present invention helps to further reduce the ammonia nitrogen content in the water.

[0061] 2. Survival rate of farmed animals Healthy crucian carp were randomly divided into 9 treatment groups, with 30 crucian carp allocated to each treatment group. The 9 treatment groups were numbered 1 to 9, and the aquaculture nutrient agents of Examples 1-6 and Comparative Examples 1-3 were added in sequence. The ratio of the amount of aquaculture nutrient used to the volume of water in the aquaculture pond was 1g:4m 3 After adding aquaculture nutrients to the aquaculture ponds, crucian carp were reared for 14 days. The survival rate of crucian carp in each treatment group was calculated on the 15th day of rearing. Survival rate (%) = (number of surviving crucian carp - initial number of crucian carp) / initial number of crucian carp × 100%.

[0062] After being treated with the aquaculture nutrient agents of Examples 1-6 and Comparative Examples 1-3, the survival rates of crucian carp in the nine treatment groups were 91.4-98.7%, which indicates that the aquaculture nutrient agent of the present invention has good biosafety.

[0063] 3. Weight gain rate of farmed animals Healthy crucian carp were randomly divided into 9 treatment groups, with 30 crucian carp allocated to each treatment group. Before treatment, the average weight of each group of crucian carp was measured, and the average weight of each group of crucian carp was recorded as W1. The 9 treatment groups were numbered 1 to 9 in sequence, and the aquaculture nutrient agents of Examples 1-6 and Comparative Examples 1-3 were used for treatment for 56 days, and the aquaculture nutrient agent was added once every 14 days into the aquaculture ponds where the 9 treatment groups were located. The ratio of the amount of aquaculture nutrient used each time to the water volume in the aquaculture pond was 1g:4m 3 During the treatment period, the fish were fed a crucian carp diet that was 2% of their total weight daily. After the treatment period, the average weight of each group of crucian carp was measured and recorded as W2. The weight gain rate (%) of crucian carp was calculated as (W2 - W1) / W1 × 100%.

[0064] Table 1 Weight gain rate of crucian carp (%)

[0065] As can be seen from Table 1, the aquaculture nutrient of Example 2-4 is better than that of Example 1 in terms of the effect of improving the weight gain rate of crucian carp, because in the aquaculture nutrient, Example 2-4 additionally adds baicalein derivatives and apigenin-7-glucoside, while Example 1 does not add baicalein derivatives and apigenin-7-glucoside; the aquaculture nutrient of Example 2-4 is better than that of Comparative Example 1 and Comparative Example 2 in terms of the effect of improving the weight gain rate of crucian carp, because in the aquaculture nutrient, Comparative Example 1 only additionally adds apigenin-7-glucoside, while Comparative Example 2 only additionally adds baicalein derivatives; the aquaculture nutrient of Example 2 is better than that of Example 3 and Example 4 in terms of the effect of improving the weight gain rate of crucian carp, because in the aquaculture nutrient, the amounts of baicalein derivatives and apigenin-7-glucoside used in the aquaculture nutrient are different. This shows that the introduction of baicalein derivatives and apigenin-7-glucoside into aquaculture nutrients can effectively improve the weight gain rate of crucian carp, and compared with the use of baicalein derivatives and apigenin-7-glucoside alone, the synergistic use of baicalein derivatives and apigenin-7-glucoside makes the aquaculture nutrient provided by the present invention more effective in improving the weight gain rate of crucian carp.

[0066] The aquaculture nutrient of Example 5-6 is superior to Example 2 in terms of the effect of improving the weight gain rate of crucian carp, because in the aquaculture nutrient, Example 5-6 additionally adds baicalein derivatives, apigenin-7-glucoside and dihydroquercetin, while Example 2 only additionally adds baicalein derivatives and apigenin-7-glucoside; the aquaculture nutrient of Example 5-6 is superior to Comparative Example 3 in terms of the effect of improving the weight gain rate of crucian carp, because in the aquaculture nutrient, Comparative Example 3 only additionally adds dihydroquercetin, but does not add baicalein derivatives and apigenin-7-glucoside; the aquaculture nutrient of Example 5 is superior to Example 6 in terms of the effect of improving the weight gain rate of crucian carp, because the amount of dihydroquercetin used in the aquaculture nutrient is different. This shows that the further addition of dihydroquercetin to the aquaculture nutrient of the present invention helps to further improve the weight gain rate of crucian carp.

[0067] The conventional operations in the operating steps of the present invention are well known to those skilled in the art and will not be described in detail here.

[0068] The embodiments described above provide a detailed description of the technical solutions of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, supplements or similar substitutions made within the scope of the principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. An aquaculture nutrient agent, comprising: superphosphate, urea, sodium humate, Bacillus subtilis culture fluid, a composite mineral agent and a nutritional supplement; the composite mineral agent comprises ferrous sulfate, zinc sulfate, manganese sulfate, copper sulfate and calcium carbonate; the nutritional supplement comprises at least lysine, methionine, vitamin C, a baicalein derivative and apigenin-7-glucoside; the baicalein derivative has a flavonoid group and a pyridine group.

2. An aquaculture nutrient according to claim 1, characterized in that: In the preparation of the baicalein derivative, baicalein is reacted with cis-2-methylcyclopropanecarboxylic acid under the action of 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride and 4-dimethylaminopyridine to obtain the baicalein derivative.

3. An aquaculture nutrient according to claim 2, characterized in that: The molar ratio of baicalein to cis-2-methylcyclopropanecarboxylic acid is 1:0.5-2.

4. An aquaculture nutrient according to claim 2, characterized in that: The molar ratio of baicalein to 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride is 1:1-3.

5. An aquaculture nutrient according to claim 2, characterized in that: The molar ratio of baicalein to 4-dimethylaminopyridine is 1:0.2-1.

6. The aquaculture nutrient according to claim 1, characterized in that: The mass ratio of the superphosphate to urea is 1:0.5-1.

7. The aquaculture nutrient according to claim 1, characterized in that: The mass ratio of the sodium humate to the superphosphate is 1:4-16.

8. The aquaculture nutrient according to claim 1, characterized in that: The usage ratio of the Bacillus subtilis liquid and sodium humate is 1 μL: 30-120 g.

9. The aquaculture nutrient according to claim 1, characterized in that: The mass ratio of the composite mineral agent to sodium humate is 1:3-12.

10. The aquaculture nutrient according to claim 1, characterized in that: The mass ratio of the nutritional supplement to sodium humate is 1:10-40.

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