Amino acid water-soluble fertilizer and production process thereof

Abstract

The invention discloses an amino acid water-soluble fertilizer and a production process thereof, and relates to the technical field of water-soluble fertilizers. Free amino acid is used as an organic nitrogen source, and the medium element calcium is combined, so that the crop quality is improved. The formula is low in cost, high in absorptivity, suitable for crop growth, simple and convenient to use and high in cost performance, and promotes the synergistic effect of nutrient elements. The method takes amino acid and calcium as raw materials, and has the characteristics of wide applicability, high output-input ratio and easiness in market promotion. The product is completely water-soluble, environment-friendly and safe, can regulate the physiological function of crops, increase the yield and amino acid content and improve the quality, and has remarkable economic benefits. In addition, activated ricinoleic acid carboxyl is combined with fucoidan enzymatic hydrolysis oligosaccharide to construct the microcapsule, so that efficient utilization of resources is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of water-soluble fertilizers, in particular to an amino acid water-soluble fertilizer and a production process thereof. Background Art

[0002] As modern agriculture's requirements for crop quality, yield and environmental friendliness continue to increase, water-soluble fertilizers have been widely used in modern agriculture, especially in facility agriculture and high-efficiency agriculture, due to their high efficiency, precise fertilization, and easy absorption and utilization.

[0003] However, traditional water-soluble fertilizers primarily rely on inorganic nitrogen sources or simple organic nitrogen compounds. While inorganic nitrogen fertilizers are quick to act, they are susceptible to leaching and volatilization, resulting in low utilization rates. Long-term, excessive use can easily lead to soil acidification and salinization, and may increase the risk of nitrate accumulation in agricultural products. Some water-soluble fertilizers that incorporate amino acids often use them as auxiliary ingredients (such as enhancers or chelating agents) at relatively low concentrations, failing to fully utilize the core role of free amino acids as a high-quality organic nitrogen source. Free amino acids can be directly absorbed and utilized by crops, offering advantages such as stimulating growth, enhancing stress resistance, and improving quality. However, existing products still fall short in utilizing free amino acids as the primary nitrogen source and in scientifically combining them with other nutrients for synergistic absorption.

[0004] Furthermore, water-soluble fertilizers containing microbial agents or biostimulants (such as seaweed extracts, oligosaccharides, and betaine) exhibit excellent biological activity, promoting crop rooting, improving nutrient absorption efficiency, and enhancing stress resistance. However, these bioactive ingredients are easily inactivated during fertilizer production, storage, and application, resulting in unstable or even complete loss of effectiveness. Conventional physical mixing or simple encapsulation techniques fail to provide sufficient and effective protection.

[0005] In summary, the development of an amino acid water-soluble fertilizer with excellent comprehensive performance, which can efficiently provide an organic nitrogen source, significantly improve the utilization rate and cost-effectiveness of secondary elements, effectively protect and deliver bioactive ingredients, and achieve efficient multi-stage utilization of functional materials, and has a feasible production process, controllable costs, and simple application, is of great practical significance for meeting the needs of improving the quality and efficiency of modern agricultural production and achieving green and sustainable development. Therefore, there is an urgent need to develop a new amino acid water-soluble fertilizer and its production process to overcome the above-mentioned shortcomings of the existing technology. Summary of the Invention

[0006] The object of the present invention is to provide an amino acid water-soluble fertilizer and a production process thereof, so as to solve the problems existing in the prior art.

[0007] In order to solve the above technical problems, the present invention provides the following technical solutions: On the one hand, an amino acid water-soluble fertilizer includes an aqueous fertilizer and bacteria-containing microcapsules, wherein the aqueous fertilizer includes the following components in the following concentrations: 100-200 g / L amino acid, 30-50 g / L calcium chloride, 3-5 g / L diatomaceous earth, 10-20 g / L potassium fulvate, 3-6 g / L magnesium sulfate heptahydrate, 0.5-1 g / L boric acid, and the balance is water; The amino acids are polyglutamic acid, methionine, cystine, lysine, tryptophan, phenylalanine, threonine, valine, leucine and isoleucine in a mass ratio of 10-15:2-4:8-9:5-8:0.1-1:2-5:0.5-2:7.5-8.2:1-3:4-7.

[0008] Furthermore, the preparation method of the bacteria-containing microcapsules is as follows: (1) 100 g of ricinoleic acid was mixed with 0.5 mol / L NHS / DMF solution, stirred at 25 °C for 30 min, and then fucoidan oligosaccharide was added, with the mass ratio of fucoidan oligosaccharide to ricinoleic acid being 5:3-5. 0.1 mol / L EDC / DMF solution was then added as a catalyst, and the mixture was reacted at 45 °C under 0.1 MPa nitrogen protection for 4 h to generate ricinoleic acid-fucoidan oligosaccharide. The reaction solution was concentrated by dialysis to a solid content of 40% to obtain a wall material solution. (2) Azospirillum and Pseudomonas fluorescens were compounded in a ratio of 3:0.5-2.5 according to the number of viable bacteria, and culture medium was added to prepare a bacterial suspension; then, 5-8 g / L of brown algae polyphenols, 20-30 g / L of betaine, and 40-50 g / L of trehalose were added to the bacterial suspension and stirred for 5 minutes to prepare a mixed core material liquid; the mixed core material liquid was added to the wall material solution with a core material to wall material mass ratio of 1:2, and then 0.8% of the total mass of the core material and wall material was added as an emulsifier for emulsification, freezing, drying, and dehydration to obtain bacteria-containing microcapsules.

[0009] Furthermore, in step (1), the molar ratio of NHS to ricinoleic acid carboxyl group is 1.2:1.

[0010] Furthermore, in step (1), the molar ratio of EDC to ricinoleic acid carboxyl is 1:1.

[0011] Furthermore, the dialysis step in step (1) is as follows: the reaction solution is purified through a dialysis bag with a molecular weight cut-off of 3500Da, and the dialysis external solution is replaced every 4 hours.

[0012] Furthermore, the dialysis external fluid is a phosphate buffer solution with a pH of 7.0 and a concentration of 0.05 mol / L.

[0013] Furthermore, the specific steps of emulsification, freezing, drying and dehydration in step (2) are as follows: emulsification is performed under high-speed shearing of 8000 rpm to form an emulsion with a particle size of 30 μm, the emulsion is sprayed into a -40°C cold trap at a pressure of 0.4 MPa through an atomizer, and the droplets are instantly frozen; and then freeze-dried in a vacuum freeze dryer at a temperature of -50°C and a vacuum degree of 0.02 MPa for 24 hours.

[0014] Furthermore, the live bacteria concentration of the bacterial suspension in step (2) is 6×10 9 CFU / mL.

[0015] On the other hand, a production process of amino acid water-soluble fertilizer includes the following process steps: adding amino acids, water, potassium humate, and diatomaceous earth according to the formula, heating to 40°C, stirring for 0.5 hours, adding calcium chloride, magnesium sulfate heptahydrate, and boric acid, stirring for 1 hour to obtain aqueous fertilizer, and finally adding bacteria-containing microcapsules 0.08 times the mass of the aqueous fertilizer.

[0016] Compared with the prior art, the beneficial effects achieved by the present invention are: The present invention uses free amino acids as an organic nitrogen source, which is one of the key fertilizer sources for improving crop quality. By adopting a ratio design of free amino acids and secondary elements, the secondary element content is higher, the cost is lower, the absorption and utilization rate is further improved, and each nutrient element promotes absorption and synergistically enhances efficiency. Compared with the use of organic fertilizers and inorganic fertilizers alone, the present invention is more suitable for crop growth, has a simple method of use, and is cost-effective. The present invention uses amino acids as the main raw material, has wide applicability, a high output-input ratio, and is easy to market.

[0017] The invention is carefully formulated from amino acids and calcium in a specific ratio. It is fully water-soluble, environmentally friendly, and safe. It regulates crop physiological functions, increases yield, increases amino acid content in crops, improves crop quality, and offers significant economic benefits.

[0018] The present invention activates the carboxyl group of ricinoleic acid and combines it with oligosaccharides obtained by enzymatic hydrolysis of fucoidan, and uses the result as the wall material to emulsify and encapsulate the bacterial flora of a combination of Azospirillum and Pseudomonas fluorescens, brown algae polyphenols, betaine, trehalose and other ingredients to form microcapsules. Ricinoleic acid acts as a protective agent during storage and becomes a colonization inducer after being decomposed during use. This clever functional transformation enables efficient resource utilization. DETAILED DESCRIPTION

[0019] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0020] In order to more clearly illustrate the method provided by the present invention, the following examples are used to describe in detail the various index testing methods of an amino acid water-soluble fertilizer prepared in the following examples. Growth condition: Take 5m 2 The soil was used as an experimental plot, and 5 Chinese cabbages were evenly distributed in each plot. Fertilization was carried out every 5 days, with 400 ml of amino acid water-soluble fertilizer applied to each plot each time. The total cultivation was 30 days. The soil compaction was observed and the average height of the Chinese cabbages was measured.

[0021] Microbial survival: One week after fertilization, soil samples from the cabbage root area were dug out and the soil around the roots was shaken off. The soil sample close to the root surface was taken as the rhizosphere soil. The number of microorganisms was determined by the plate gradient dilution method, and beef extract peptone agar medium was used to determine the bacteria. Soil samples were taken from each treatment area three times and the average data was measured.

[0022] Microcapsule storage and preservation: The bacteria-containing microcapsules of the examples and comparative examples were stored in the dark at 25°C and 60% humidity for 3 months. The amino acid water-soluble fertilizer was then prepared. The number of microorganisms in the fertilizer after 3 months was determined using a plate gradient dilution method. The bacteria were determined using beef extract peptone agar medium, with three samples taken and the average data obtained. The survival rates of Azospirillum and Pseudomonas fluorescens were then calculated. The microcapsules, after storage for three months, were then mixed with the aqueous fertilizer for growth testing.

[0023] Example 1: A production process for amino acid water-soluble fertilizer, comprising the following process steps: (1) The RC2-3mut strain of Flavobacterium was inoculated into a liquid culture medium and cultured in a shaking incubator at 30°C and 200 rpm for 24 h to obtain a seed solution; the seed solution was then inoculated into a fermentation medium at a 10 wt% inoculation rate and fermented in a 5 L fermenter at 30°C and 200 rpm for 72 h; the fermentation liquid was centrifuged at 4°C and 10,000 rpm for 5 min, the supernatant was discarded, and the precipitate was dissolved with 5 times the volume of 20 mM Tris-HCl solution with a pH of 8.0. The cells were ultrasonically disrupted at 800 W for 10 min under ice bath protection, and centrifuged at 4°C and 10,000 rpm for 5 min. The supernatant was taken to obtain fucoidanase; The components of the liquid culture medium include 10 g / L of fucoidan, 10 g / L of peptone, and 5 g / L of ammonium nitrate, which is prepared with permeated seawater and has a natural pH. The fermentation culture medium includes: 1% fucoidan (accounting for the mass ratio of the culture medium) and 2% beef extract (accounting for the mass ratio of the culture medium), which is prepared with permeated seawater and has a natural pH. A PBS buffer solution with a pH of 8.0 and a concentration of 24 mM is prepared, and fucoidan with a molecular weight of 5000 is dissolved in the above buffer to prepare a 1 wt% fucoidan solution. A PBS buffer solution with a pH of 8.0 and a concentration of 24 mM is prepared, and fucoidanase is dissolved in the above buffer solution to prepare an active concentration of 1000 U / m L of fucoidanase solution; add 1 mL of 1000 U / mL fucoidanase to 10 mL of 1 wt% fucoidan solution, react at 30°C and 100 rpm in a water bath for 2 hours, and then water bath at 100°C for 10 minutes to terminate the reaction; after cooling, centrifuge at 8000 rpm for 10 minutes, take the supernatant, filter out oligosaccharides with a molecular weight of less than 100 kDa using an ultrafiltration membrane system, and freeze-dry at -40°C for 2 hours to obtain fucoidan oligosaccharides; take 100 g of ricinoleic acid and dissolve it in 500 mL of anhydrous DMF, add 0.5 mol / L NHS / DMF solution and mix, the molar ratio of NHS to ricinoleic acid carboxyl group is 1.2:1, then stirred at 25°C for 30 minutes to activate the carboxyl group at a stirring speed of 120 rpm; then added fucoidan oligosaccharide, the mass ratio of fucoidan oligosaccharide to ricinoleic acid was 5:3, and then added 0.1 mol / L EDC / DMF solution as a catalyst, the molar ratio of EDC to ricinoleic acid carboxyl was 1:1, and reacted at 45°C under 0.1 MPa nitrogen protection for 4 hours to generate ricinoleic acid-fucoidan oligosaccharide, and the reaction solution was purified by a dialysis bag with a molecular weight cutoff of 3500 Da. The dialysis external solution was a phosphate buffer solution with a pH of 7.0 and a concentration of 0.05 mol / L. The dialysis external solution was replaced every 4 hours and concentrated to a solid content of 40% to obtain a wall material solution; (2) Azospirillum and Pseudomonas fluorescens were mixed at a live bacterial count ratio of 3:0.5 and added to the culture medium to prepare a bacterial suspension with a live bacterial concentration of 6×10 9CFU / mL; then, 5 g / L of brown algae polyphenols, 20 g / L of betaine, and 40 g / L of trehalose were added to the bacterial suspension, and stirred at 60 rpm for 5 minutes to obtain a mixed core material liquid; the mixed core material liquid was added to the wall material solution, with the mass ratio of the core material to the wall material being 1:2, and then 0.8% of the total mass of the core material and the wall material was added as an emulsifier to emulsify under high-speed shear at 8000 rpm to form an emulsion with a particle size of 30 μm, and the emulsion was sprayed into a -40°C cold trap at a pressure of 0.4 MPa through an atomizer, and the droplets were instantly frozen; then, the mixture was freeze-dried in a vacuum freeze dryer at a temperature of -50°C and a vacuum degree of 0.02 MPa for 24 hours to obtain bacteria-containing microcapsules; the components of the culture solution included 0.5 wt% of rhamnolipid, 0.1 wt% of sodium glutamate, 5 wt% of starch, and the rest was a PBS buffer solution with a pH of 7.0 and a concentration of 100 mM. The components of the culture solution include 0.5wt% rhamnolipid, 0.1wt% sodium glutamate, 5wt% starch, and the rest is a PBS buffer solution with a pH of 7.0 and a concentration of 100mM; (3) According to the following concentrations of components: 180 g / L amino acid, 35 g / L calcium chloride, 3 g / L diatomaceous earth, 10 g / L potassium humate, 3 g / L magnesium sulfate heptahydrate, 1 g / L boric acid, and the balance being water, weigh amino acids, water, potassium humate, and diatomaceous earth, heat to 40°C, stir for 0.5 h, then add calcium chloride, magnesium sulfate heptahydrate, and boric acid, stir for 1 h to obtain an aqueous fertilizer, and finally add 0.08 times the mass of the aqueous fertilizer containing microcapsules, wherein the amino acids are polyglutamic acid, methionine, cystine, lysine, tryptophan, phenylalanine, threonine, valine, leucine, and isoleucine in a mass ratio of 10:3:8:7:1:3:1:8:2:5.

[0024] Example 2: A production process for an amino acid water-soluble fertilizer, comprising the following process steps: (1) Fucoido oligosaccharide was prepared by the same method as in Example 1; 100 g of ricinoleic acid was dissolved in 500 mL of anhydrous DMF, and 0.5 mol / L of NHS / DMF solution was added and mixed, with the molar ratio of NHS to ricinoleic acid carboxyl being 1.2:1, and then the carboxyl groups were activated by stirring at 25°C for 30 min at a stirring speed of 120 rpm; fucoido oligosaccharide was then added, with the mass ratio of fucoido oligosaccharide to ricinoleic acid being 5:4, and 0.1 mol / L of EDC / DMF solution was added as a catalyst, with the molar ratio of EDC to ricinoleic acid carboxyl being 1:1, and the reaction was carried out at 45°C under 0.1 MPa nitrogen protection for 4 h to generate ricinoleic acid-fucoido oligosaccharide, and the reaction solution was purified by a dialysis bag with a molecular weight cutoff of 3500 Da, and the dialysis external solution was a phosphate buffer solution with a pH of 7.0 and a concentration of 0.05 mol / L. The dialysis external solution was replaced every 4 h and concentrated to a solid content of 40% to obtain a wall material solution; (2) Azospirillum and Pseudomonas fluorescens were mixed at a live bacterial count ratio of 3:1.5 and added to the culture medium to prepare a bacterial suspension with a live bacterial concentration of 6×10 9 CFU / mL; then, 7 g / L of brown algae polyphenols, 25 g / L of betaine, and 45 g / L of trehalose were added to the bacterial suspension, and stirred at 60 rpm for 5 min to obtain a mixed core material liquid; the mixed core material liquid was added to the wall material solution, with the mass ratio of the core material to the wall material being 1:2, and then 0.8% of the total mass of the core material and the wall material was added as an emulsifier to emulsify at 8000 rpm under high-speed shear to form an emulsion with a particle size of 30 μm, and the emulsion was sprayed into a -40°C cold trap at a pressure of 0.4 MPa through an atomizer, and the droplets were instantly frozen; then, the mixture was freeze-dried in a vacuum freeze dryer at a temperature of -50°C and a vacuum degree of 0.02 MPa for 24 h to obtain bacteria-containing microcapsules; the components of the culture solution included 0.5 wt% of rhamnolipid, 0.1 wt% of sodium glutamate, 5 wt% of starch, and the rest was a PBS buffer solution with a pH of 7.0 and a concentration of 100 mM; (3) According to the following concentrations of components: 180 g / L amino acid, 35 g / L calcium chloride, 3 g / L diatomaceous earth, 10 g / L potassium humate, 3 g / L magnesium sulfate heptahydrate, 1 g / L boric acid, and the balance being water, weigh amino acids, water, potassium humate, and diatomaceous earth, heat to 40°C, stir for 0.5 h, then add calcium chloride, magnesium sulfate heptahydrate, and boric acid, stir for 1 h to obtain an aqueous fertilizer, and finally add 0.08 times the mass of the aqueous fertilizer containing microcapsules, wherein the amino acids are polyglutamic acid, methionine, cystine, lysine, tryptophan, phenylalanine, threonine, valine, leucine, and isoleucine in a mass ratio of 10:3:8:7:1:3:1:8:2:5.

[0025] Example 3: A production process for amino acid water-soluble fertilizer, comprising the following process steps: (1) Fucoido oligosaccharide was prepared by the same method as in Example 1; 100 g of ricinoleic acid was dissolved in 500 mL of anhydrous DMF, and 0.5 mol / L of NHS / DMF solution was added and mixed, with the molar ratio of NHS to ricinoleic acid carboxyl being 1.2:1, and then the carboxyl groups were activated by stirring at 25°C for 30 min at a stirring speed of 120 rpm; fucoido oligosaccharide was then added, with the mass ratio of fucoido oligosaccharide to ricinoleic acid being 5:3, and 0.1 mol / L of EDC / DMF solution was added as a catalyst, with the molar ratio of EDC to ricinoleic acid carboxyl being 1:1, and the reaction was carried out at 45°C under 0.1 MPa nitrogen protection for 4 h to generate ricinoleic acid-fucoido oligosaccharide, and the reaction solution was purified by a dialysis bag with a molecular weight cutoff of 3500 Da, and the dialysis external solution was a phosphate buffer solution with a pH of 7.0 and a concentration of 0.05 mol / L. The dialysis external solution was replaced every 4 h and concentrated to a solid content of 40% to obtain a wall material solution; (2) Azospirillum and Pseudomonas fluorescens were mixed at a live bacterial count ratio of 3:2.5 and added to the culture medium to prepare a bacterial suspension with a live bacterial concentration of 6×10 9 CFU / mL; then, 8 g / L of brown algae polyphenols, 30 g / L of betaine, and 50 g / L of trehalose were added to the bacterial suspension, and stirred at 60 rpm for 5 min to obtain a mixed core material liquid; the mixed core material liquid was added to the wall material solution, with the mass ratio of the core material to the wall material being 1:2, and then 0.8% of the total mass of the core material and the wall material was added as an emulsifier to emulsify at 8000 rpm under high-speed shear to form an emulsion with a particle size of 30 μm, and the emulsion was sprayed into a -40°C cold trap at a pressure of 0.4 MPa through an atomizer, and the droplets were instantly frozen; then, the mixture was freeze-dried in a vacuum freeze dryer at a temperature of -50°C and a vacuum degree of 0.02 MPa for 24 h to obtain bacteria-containing microcapsules; the components of the culture solution included 0.5 wt% of rhamnolipid, 0.1 wt% of sodium glutamate, 5 wt% of starch, and the rest was a PBS buffer solution with a pH of 7.0 and a concentration of 100 mM; (3) According to the following concentrations of components: 180 g / L amino acid, 35 g / L calcium chloride, 3 g / L diatomaceous earth, 10 g / L potassium humate, 3 g / L magnesium sulfate heptahydrate, 1 g / L boric acid, and the balance being water, weigh amino acids, water, potassium humate, and diatomaceous earth, heat to 40°C, stir for 0.5 h, then add calcium chloride, magnesium sulfate heptahydrate, and boric acid, stir for 1 h to obtain an aqueous fertilizer, and finally add 0.08 times the mass of the aqueous fertilizer containing microcapsules, wherein the amino acids are polyglutamic acid, methionine, cystine, lysine, tryptophan, phenylalanine, threonine, valine, leucine, and isoleucine in a mass ratio of 10:3:8:7:1:3:1:8:2:5.

[0026] Comparative Example 1; The difference between Comparative Example 1 and Example 2 lies in the difference in steps (1) and (2). Steps (1) and (2) are changed to: (1) 2.0% chitosan acetate solution with a pH of 5.0 and 3.5% fucoidan aqueous solution with a pH of 6.8 are mixed in a volume ratio of 3:2, and stirred at a high speed of 500 rpm for 30 min in a 45°C water bath to form a uniform milky white colloid, and then 0.5% glycerol of the total mass is added as a plasticizer, and stirring is continued for 10 min to obtain a composite colloid; the composite colloid is cooled to 25°C, and 1.0% sodium tripolyphosphate solution is added dropwise at a rate of 2 ml / min, the volume of the sodium tripolyphosphate solution being one-sixth of the total amount of the colloid, while maintaining a stirring speed of 300 rpm. After the addition is completed, the mixture is allowed to stand for cross-linking for 60 min to obtain an elastic gel block; (2) Azospirillum and Pseudomonas fluorescens were mixed at a live bacterial count ratio of 3:1.5 and added to the culture medium to prepare a bacterial suspension with a live bacterial concentration of 6×10 9CFU / mL; then, 7g / L of brown algae polyphenols, 25g / L of betaine, and 45g / L of trehalose were added to the bacterial suspension, stirred at 60rpm for 5min to prepare a mixed core liquid, which was then evenly dispersed into the composite gel; granulation was performed using a screw extruder with a 30μm pore size template, and the wet granules were collected and transferred to a freeze dryer for sublimation dehydration at -50°C and 10Pa vacuum for 24h to obtain bacteria-containing microcapsules; the components of the culture solution included 0.5wt% rhamnolipid, 0.1wt% sodium glutamate, 5wt% starch, and the rest was a PBS buffer solution with a pH of 7.0 and a concentration of 100mM. The remaining steps were the same as in Example 2.

[0027] Comparative Example 2: The difference between Comparative Example 2 and Example 2 is that step (2) is different. Step (2) is changed to: adding Azospirillum to the culture medium to prepare a bacterial suspension with a viable bacterial concentration of 6×10 9 CFU / mL; then, 7g / L of brown algae polyphenols, 25g / L of betaine, and 45g / L of trehalose were added to the bacterial suspension and stirred at 60rpm for 5min to obtain a mixed core material liquid; the mixed core material liquid was added to the wall material solution, the core material to wall material mass ratio was 1:2, and 0.8% of the total mass of the core material and wall material was added as an emulsifier to form an emulsion with a particle size of 30μm under 8000rpm high shear, and the emulsion was sprayed into a -40℃ cold trap at a pressure of 0.4MPa through an atomizer, and the droplets were instantly frozen; then, in a vacuum freeze dryer, freeze-dried for 24h at a temperature of -50℃ and a vacuum degree of 0.02MPa to obtain bacteria-containing microcapsules; the components of the culture solution included 0.5wt% of rhamnolipid, 0.1wt% of sodium glutamate, 5wt% of starch, and the rest was a PBS buffer solution with a pH of 7.0 and a concentration of 100mM. The remaining steps were the same as in Example 2.

[0028] Comparative Example 3: The difference between Comparative Example 3 and Example 2 is that step (2) is different. Step (2) is changed to: Pseudomonas fluorescens is added to the culture medium to prepare a bacterial suspension with a live bacterial concentration of 6×10 9CFU / mL; then, 7g / L of brown algae polyphenols, 25g / L of betaine, and 45g / L of trehalose were added to the bacterial suspension and stirred at 60rpm for 5min to obtain a mixed core material liquid; the mixed core material liquid was added to the wall material solution, the core material to wall material mass ratio was 1:2, and 0.8% of the total mass of the core material and wall material was added as an emulsifier to form an emulsion with a particle size of 30μm under 8000rpm high shear, and the emulsion was sprayed into a -40℃ cold trap at a pressure of 0.4MPa through an atomizer, and the droplets were instantly frozen; then, in a vacuum freeze dryer, freeze-dried for 24h at a temperature of -50℃ and a vacuum degree of 0.02MPa to obtain bacteria-containing microcapsules; the components of the culture solution included 0.5wt% of rhamnolipid, 0.1wt% of sodium glutamate, 5wt% of starch, and the rest was a PBS buffer solution with a pH of 7.0 and a concentration of 100mM. The remaining steps were the same as in Example 2.

[0029] Comparative Example 4 The difference between Comparative Example 4 and Example 2 is that urea is used instead of amino acid. The remaining steps are the same as those in Example 2.

[0030] Effect Examples Tables 1 and 2 below show the performance analysis results of a water-soluble amino acid fertilizer using Examples 1 to 3 of the present invention and Comparative Examples 1 to 4.

[0031] Table 1 Test data of microcapsule fertilizer before storage

[0032] Table 2 Fertilizer test data after three months of storage

[0033] The present invention combines activated ricinoleic acid carboxyl groups with enzymatically hydrolyzed oligosaccharides from fucoidan to create microcapsules that encapsulate components such as Azospirillum and Pseudomonas fluorescens. The ricinoleic acid acts as a protective agent during storage and a colonization inducer during use, achieving efficient resource utilization. During storage, the dense hydrophobic film formed by ricinoleic acid on the surface of the microcapsules effectively isolates the intrusion of external water and oxygen. Combined with trehalose, it ensures that the bacterial flora maintains extremely high survival activity during long-term storage, protecting the active factors from oxidation and inactivation. Amino acids then form a hydrated gel network with water-retention capacity. By tailoring the ratio of amino acids to microcapsules, the amino acids effectively buffer the impact of external humidity fluctuations on the internal bacterial cells. When the fertilizer is applied to the soil, microbial enzymes in the environment begin to break down ricinoleic acid. The product, a precursor to jasmonic acid, effectively stimulates the secretion of large amounts of extracellular polysaccharides by Azospirillum, forming a biofilm and significantly enhancing its colonization ability on crop root surfaces. The released Pseudomonas fluorescens in the core material dissolves insoluble phosphorus in the soil, synergizing with Azospirillum to significantly improve the efficiency of nitrogen and phosphorus nutrient acquisition by crops. Polyglutamic acid exhibits excellent water- and nutrient-retention properties in the soil, forming a slow-release zone around the roots, greatly improving water and nutrient absorption by crops.

[0034] Example 4 The same method as in Example 2 was used to prepare the bacteria-containing microcapsules. The process of preparing the amino acid water-soluble fertilizer was the same as in Example 2, but the ratio of amino acids to calcium chloride was changed. The effects of the amino acid and calcium chloride formula design on crops can be seen in Table 3: Table 3 Effects of amino acid and calcium chloride formulation design on crops

[0035] In the present invention, amino acids (nitrogen source) and calcium chloride (calcium source) have a synergistic relationship. Calcium chloride can stabilize the cell wall structure and promote the transport and absorption of amino acids. Through formula design, the optimal nutrient ratio under this fertilizer system is achieved, thereby achieving optimized crop growth.

[0036] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be encompassed therein. Any reference in a claim should not be construed as limiting the claim to which it relates.

Claims

1. An amino acid water-soluble fertilizer, comprising an aqueous fertilizer and bacteria-containing microcapsules, characterized in that: The aqueous fertilizer comprises the following components in the following concentrations: 100-200 g / L amino acid, 30-50 g / L calcium chloride, 3-5 g / L diatomaceous earth, 10-20 g / L potassium fulvate, 3-6 g / L magnesium sulfate heptahydrate, 0.5-1 g / L boric acid, and the balance is water; The amino acids are polyglutamic acid, methionine, cystine, lysine, tryptophan, phenylalanine, threonine, valine, leucine and isoleucine in a mass ratio of 10-15:2-4:8-9:5-8:0.1-1:2-5:0.5-2:7.5-8.2:1-3:4-7.

2. A water-soluble amino acid fertilizer according to claim 1, characterized in that, The preparation method of the bacteria-containing microcapsules is as follows: (1) 100 g of ricinoleic acid was mixed with 0.5 mol / L NHS / DMF solution, stirred at 25 °C for 30 min, and then fucoidan oligosaccharide was added, with the mass ratio of fucoidan oligosaccharide to ricinoleic acid being 5:3-5. 0.1 mol / L EDC / DMF solution was then added as a catalyst, and the mixture was reacted at 45 °C under 0.1 MPa nitrogen protection for 4 h to generate ricinoleic acid-fucoidan oligosaccharide. The reaction solution was concentrated by dialysis to a solid content of 40% to obtain a wall material solution. (2) Azospirillum and Pseudomonas fluorescens were compounded in a ratio of 3:0.5-2.5 according to the number of viable bacteria, and culture medium was added to prepare a bacterial suspension; then, 5-8 g / L of brown algae polyphenols, 20-30 g / L of betaine, and 40-50 g / L of trehalose were added to the bacterial suspension and stirred for 5 minutes to prepare a mixed core material liquid; the mixed core material liquid was added to the wall material solution with a core material to wall material mass ratio of 1:2, and then 0.8% of the total mass of the core material and wall material was added as an emulsifier for emulsification, freezing, drying, and dehydration to obtain bacteria-containing microcapsules.

3. A water-soluble amino acid fertilizer according to claim 2, characterized in that, The molar ratio of NHS to ricinoleic acid carboxyl in step (1) is 1.2:

1.

4. A water-soluble amino acid fertilizer according to claim 2, characterized in that, In the step (1), the molar ratio of EDC to ricinoleic acid carboxyl is 1:

1.

5. A water-soluble amino acid fertilizer according to claim 4, characterized in that, The dialysis step in step (1) is as follows: the reaction solution is purified through a dialysis bag with a molecular weight cut-off of 3500Da, and the dialysis external solution is replaced every 4 hours.

6. A water-soluble amino acid fertilizer according to claim 2, characterized in that, The dialysis external fluid is a phosphate buffer solution with a pH of 7.0 and a concentration of 0.05 mol / L.

7. A water-soluble amino acid fertilizer according to claim 2, characterized in that, The specific steps of emulsification, freezing, drying and dehydration in step (2) are as follows: emulsification under high-speed shearing of 8000 rpm to form an emulsion with a particle size of 30 μm, the emulsion is sprayed into a -40°C cold trap at a pressure of 0.4 MPa through an atomizer, and the droplets are instantly frozen; and then freeze-dried in a vacuum freeze dryer at a temperature of -50°C and a vacuum degree of 0.02 MPa for 24 hours.

8. A water-soluble amino acid fertilizer according to claim 2, characterized in that, The live bacteria concentration of the bacterial suspension in step (2) is 6×10 9 CFU / mL.

9. A production process for amino acid water-soluble fertilizer, characterized in that: The process comprises the following steps: adding amino acids, water, potassium fulvic acid and diatomaceous earth according to the formula, heating to 40°C, stirring for 0.5 hours, adding calcium chloride, magnesium sulfate heptahydrate and boric acid, stirring for 1 hour to obtain aqueous fertilizer, and finally adding bacteria-containing microcapsules in an amount 0.08 times the mass of the aqueous fertilizer.

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