Gamma-polyglutamic acid synergistic dyeing diammonium phosphate fertilizer, preparation method and application

Abstract

The invention discloses a gamma-polyglutamic acid synergistic dyeing diammonium phosphate fertilizer as well as a preparation method and application thereof, the preparation method comprises the steps of gamma-polyglutamic acid fermentation liquor preparation, fertilizer dyeing and fertilizer forming, and the prepared diammonium phosphate fertilizer comprises gamma-polyglutamic acid fermentation liquor, a diammonium phosphate fertilizer and a yellow dye. Compared with the prior art, the coloring agent and the dye of the diammonium phosphate fertilizer are low in dosage, the coloring cost is effectively reduced, the coloring operation is simple, the existing production process and equipment are not required to be greatly adjusted, the market competitiveness of the product is further improved, the fertilizer efficiency of the diammonium phosphate is improved, and the production cost is reduced. The fertilizer has an obvious promotion effect on growth, development and yield improvement of crops.

Description

Technical Field

[0001] The invention belongs to the technical field of fertilizer production, and in particular relates to a gamma-polyglutamic acid synergistic dyeing diammonium phosphate fertilizer, a preparation method and an application thereof. Background Art

[0002] At present, most phosphate fertilizers are produced with wet phosphoric acid as raw material. However, due to the unstable quality of phosphate rock, its impurity content is unstable, which directly leads to the instability of the appearance color of phosphate fertilizer products during the production process, thereby reducing the market competitiveness of phosphate fertilizer products. Therefore, the appearance color of the products can be unified by dyeing. Taking the dyeing of diammonium phosphate fertilizer (DAP) as an example, most companies use the "internal dyeing and external packaging" technology process for coloring, where "internal dyeing" refers to adding raw materials containing "pigment" in a certain process before granulation; and "external packaging" refers to wrapping a layer of oil film on the surface of the particles after granulation, which can increase the slow-release effect of the fertilizer and prevent the fertilizer from absorbing moisture and agglomerating. However, in actual production, it was found that the above-mentioned internal dyeing and external packaging technology process has the problem of large amount of colorants and dyes used and high cost, and the dyeing effect is not good, and the appearance color of the product is unstable. Summary of the invention

[0003] The first purpose of the present invention is to provide a γ-polyglutamate synergistic dyeing diammonium phosphate fertilizer, the second purpose is to provide a preparation method of the γ-polyglutamate synergistic dyeing diammonium phosphate fertilizer, and the third purpose is to provide an application of the γ-polyglutamate synergistic dyeing diammonium phosphate fertilizer in crop planting.

[0004] The first objective of the present invention is achieved through the following technical scheme: the diammonium phosphate fertilizer comprises the following components by weight percentage: 0.4-0.7% of gamma-polyglutamic acid fermentation liquid, 98-99.5% of diammonium phosphate fertilizer, and 1.2-1.3% of yellow dye.

[0005] The second objective of the present invention is achieved through the following technical solutions: 1) Preparation of γ-polyglutamic acid fermentation liquid: activating, diluting and fermenting Bacillus velez YWF-075 strain to obtain γ-polyglutamic acid fermentation liquid; 2) Fertilizer dyeing: During the neutralization process of producing diammonium phosphate in wet-process phosphoric acid, add γ-polyglutamic acid fermentation liquid and yellow dye in proportion, and then continue to stir and dissolve. Under the continuous stirring condition, pass ammonia into the wet-process phosphoric acid containing γ-polyglutamic acid fermentation liquid and yellow dye to react to the end point of diammonium phosphate (DAP) fertilizer product; and continue to pass ammonia for 25-35 minutes; 3) Fertilizer molding: the slurry is granulated into diammonium phosphate (DAP) granular product by spray coating, which is diammonium phosphate fertilizer. The finished product has a uniform yellow color.

[0006] Beneficial Effects

[0007] 1) The γ-polyglutamic acid of the present invention is a glutamic acid polymer, which is a biopolymer containing a large number of amide bonds and free carboxyl groups in its molecular structure. It can not only effectively absorb water vapor in the air, but also be degraded by microorganisms in the environment. The γ-polyglutamic acid absorbs moisture in the soil and then degrades it, effectively improving the slow-release effect of diammonium phosphate fertilizer. On the other hand, polyglutamic acid itself has a certain viscosity, which can significantly improve the coloring effect of diammonium phosphate fertilizer, further ensure the uniformity and stability of the coloring of diammonium phosphate fertilizer, and achieve a unified appearance color of the product. 2) Compared with the prior art, the amount of colorant and dye used in the diammonium phosphate fertilizer of the present invention is low, which effectively reduces the coloring cost. The coloring operation is simple and can be achieved without major adjustments to the existing production process and equipment, further improving the market competitiveness of the product; 3) In order to solve the problem of unstable appearance color of phosphate fertilizer products, 0.4~0.7% of γ-polyglutamic acid (3.5%) is added during the phosphate fertilizer production process, especially in the process of wet phosphoric acid and ammonia reaction to produce diammonium phosphate (DAP) fertilizer. This is not only conducive to uniform coloring of the dye, but also helps to improve the efficiency of diammonium phosphate fertilizer, and has a significant promoting effect on crop growth and development and yield increase. DETAILED DESCRIPTION

[0008] In order to enable those skilled in the art to better understand the technical solution of the present invention, the specific implementation methods are described in detail below in conjunction with embodiments.

[0009] The gamma-polyglutamic acid synergistic dyed diammonium phosphate fertilizer of the invention has an appearance of uniformly colored yellow granules. The diammonium phosphate fertilizer comprises the following components by weight percentage: 0.4-0.7% of gamma-polyglutamic acid fermentation liquid, 98-99.5% of diammonium phosphate fertilizer, and 1.2-1.3% of yellow dye.

[0010] The classification name of the Bacillus Velez YWF-075 of the present invention is: Bacillus Velez ( Bacillus from Velez )YWF-075, the deposit registration number is CCTCC NO: M 20242105, the deposit date is September 27, 2024, the status is: alive, the depository unit is China Center for Type Culture Collection, and the deposit address is Wuhan University, China.

[0011] Example 1

[0012] The preparation method of γ-polyglutamic acid fermentation broth comprises the following steps: 1) Plate culture: Take the Bacillus Velez YWF-075 preserved in a glycerol tube and spread it on the LB slant medium. The LB slant medium is prepared using a known formula. Culture at 33°C for 24-48 hours until the bacterial growth logarithmic phase. 2) Preparation of bacterial suspension: Use sterile water to elute the bacterial moss on the LB slant medium to make an effective bacterial count of 10 8 ~10 9 cfu / ml bacterial suspension; 3) γ-polyglutamic acid seed tank fermentation: After the seed culture medium is sterilized and cooled to about 33°C, the bacterial suspension is inoculated into the seed tank at a 5% inoculation rate for seed culture to obtain the seed liquid. The culture process is as follows: after standing for 10 hours, start stirring at 220 rpm / min, the temperature is 33°C, and the pH is natural; 4) Fermentation culture: After the fermentation medium is sterilized and cooled to 33°C, the seed liquid is introduced into the fermentation tank at a 10% inoculation rate to finally obtain γ-polyglutamic acid fermentation liquid. The culture process is shown in Table 1. Sampling: 0h, 4h, 8h, ... Take samples every 4 hours and record the pH value, DO value, temperature, tank pressure, stirring speed, until the tank is released, and record the volume of the tank released.

[0013] Canning indicators: After the bacterial OD has grown for 48 hours and reaches above 0.6, it begins to drop rapidly and is sterilized at 121℃ for 5 minutes before canning.

[0014] The seed culture medium formula of step 1 includes: yeast extract 5-10 g / L, tryptone 6-15 g / L, magnesium sulfate heptahydrate 0.1-0.5 g / L, dipotassium hydrogen phosphate 0.1-0.5 g / L, glucose (separated and digested separately) 20-30 g / L, and the pH is adjusted to 7.2-7.4 with 20% NaOH.

[0015] The fermentation medium formula includes: 50-80 g / L sodium glutamate, 5-15 g / L ammonium sulfate, 2-6 g / L tryptone, 0.2-0.5 g / L magnesium sulfate heptahydrate, 0.01-0.06 g / L ferrous sulfate heptahydrate, 5-10 g / L yeast extract, 5-15 g / L potassium sulfate, 0.1-0.5 g / L calcium sulfate, 0.10-0.20 ml / L defoaming agent, and 50-100 g / L glucose (separated and defoamed separately).

[0016] Example 2

[0017] The specific steps of the preparation method of γ-polyglutamic acid synergistic dyeing diammonium phosphate fertilizer are as follows: 1) Preparation of γ-polyglutamic acid fermentation liquid: activating, diluting and fermenting Bacillus velez YWF-075 strain to obtain γ-polyglutamic acid fermentation liquid, i.e., the γ-polyglutamic acid fermentation liquid obtained by the method described in Example 1; 2) Fertilizer dyeing: During the neutralization process of the wet-process phosphoric acid to produce diammonium phosphate (Due to the existing known production process of the wet-process phosphoric acid to produce diammonium phosphate, no additional details are given here), 0.4-0.7% of γ-polyglutamic acid fermentation broth and 1.2-1.3% of yellow dye are added in proportion, and the yellow dye is lemon yellow, based on the total weight percentage, and then stirred and dissolved continuously. Under the continuous stirring condition, a certain amount of ammonia is continuously introduced into the wet-process phosphoric acid containing the γ-polyglutamic acid fermentation broth and the yellow dye to react to the end point of the diammonium phosphate (DAP) fertilizer product; and the ammonia is continued for 25-35 minutes to ensure sufficient reaction; 3) Fertilizer molding: the slurry is granulated into diammonium phosphate (DAP) granular product by spray coating. The granular product is diammonium phosphate fertilizer, and the finished product has a uniform yellow appearance.

[0018] 4) Detection of γ-polyglutamic acid content in the diammonium phosphate fertilizer prepared in Example 2 The diammonium phosphate fertilizer prepared by high performance liquid chromatography according to Example 2 is tested for gamma-polyglutamic acid content, with sodium sulfate solution as mobile phase, with different contents of gamma-polyglutamic acid standard solution ultraviolet absorption value as detection object, high performance liquid chromatography is used to measure gamma-polyglutamic acid content, and the detection result is gamma-polyglutamic acid content ≥3.5%, and the appearance is yellow uniform yellow liquid with certain viscosity. And when the detection content ≥35g / L, the viscosity is detected by viscometer between 3800mPa.s~4100mPa.s. Because of its viscosity and color, there are certain advantages in uniformly mixing yellow dyes and diammonium phosphate products, and the detection of gamma-polyglutamic acid provides material for the next step of polyglutamic acid fermentation liquid as diammonium phosphate fertilizer coloring synergist.

[0019] The γ-polyglutamic acid content of the diammonium phosphate fertilizer prepared in Example 2 was detected by high performance liquid chromatography. The theoretical content was 175 mg / kg, and the detected γ-polyglutamic acid content was ≥150 mg / Kg, which met the technical index requirements of polyglutamic acid diammonium phosphate.

[0020] Example 3

[0021] Effects of γ-polyglutamic acid diammonium phosphate fertilizer on the growth and development of Chinese cabbage The potted cabbage was used as the test object, and three treatments were set up in the test, wherein treatment 1 was a blank control, treatment 2 was a conventional diammonium phosphate fertilizer without γ-polyglutamic acid, and treatment 3 was a diammonium phosphate fertilizer containing γ-polyglutamic acid prepared by method 2. The experimental results are shown in Table 2 below. After 30 days of treatment, the agronomic traits of each cabbage were measured, including plant height, leaf length, leaf width, SPAD value and single plant weight. The results showed that treatments 3 and 2 had a significant promoting effect compared with the blank control treatment 1; and at the same fertilizer application rate, treatment 3 was superior to treatment 2 in plant height, leaf length, leaf width, SPAD value and single plant weight, especially in single plant weight.

[0022] Example 4

[0023] Effects of fertilizer containing γ-polyglutamic acid and diammonium phosphate on potato production According to the fertilizer field demonstration method, two treatments were set up, and fertilizers containing γ-polyglutamic acid diammonium phosphate and fertilizers without γ-polyglutamic acid diammonium phosphate were applied respectively. The fertilizer without γ-polyglutamic acid diammonium phosphate was used as the control, and the fertilizer containing γ-polyglutamic acid diammonium phosphate was used as the treatment to compare their yield-increasing effects on potatoes. The results are shown in Table 3 below.

[0024] The results are: the fertilizer product containing γ-polyglutamate diammonium phosphate performed excellently in potato yield. Compared with the treatment without γ-polyglutamate diammonium phosphate fertilizer, the average yield per mu increased by about 23%. The fertilizer containing γ-polyglutamate diammonium phosphate can not only promote the robust growth of the aboveground part, but also promote the development of the underground part, thereby increasing potato yield and significantly increasing production and income.

Claims

1. A γ-polyglutamic acid synergistic dyeing diammonium phosphate fertilizer, characterized in that: The diammonium phosphate fertilizer comprises the following components by weight percentage: 0.4-0.7% of gamma-polyglutamic acid fermentation liquid, 98-99.5% of diammonium phosphate fertilizer, and 1.2-1.3% of yellow dye.

2. The γ-polyglutamic acid synergistic dyeing diammonium phosphate fertilizer according to claim 1, characterized in that: The diammonium phosphate fertilizer is in the form of evenly colored yellow granules.

3. A method for preparing the γ-polyglutamic acid synergistic dyeing diammonium phosphate fertilizer according to claim 1, characterized in that: 1) Preparation of γ-polyglutamic acid fermentation liquid: activating, diluting and fermenting Bacillus velezensis YWF-075 strain to obtain γ-polyglutamic acid fermentation liquid; 2) Fertilizer dyeing: During the neutralization process of producing diammonium phosphate in wet-process phosphoric acid, add γ-polyglutamic acid fermentation liquid and yellow dye in proportion, and then continue to stir and dissolve. Under the continuous stirring condition, pass ammonia into the wet-process phosphoric acid containing γ-polyglutamic acid fermentation liquid and yellow dye to react to the end point of diammonium phosphate (DAP) fertilizer product; and continue to pass ammonia for 25-35 minutes; 3) Fertilizer molding: the slurry is granulated into diammonium phosphate (DAP) granular product by spray coating, which is diammonium phosphate fertilizer. The finished product has a uniform yellow color.

4. The method for preparing the γ-polyglutamic acid synergistic dyeing diammonium phosphate fertilizer according to claim 3, characterized in that: In step 1, the activated Bacillus subtilis YWF-075 was diluted with sterile water to prepare an effective bacterial count of 10 8 ~10 9 cfu / ml bacterial suspension.

5. The method for preparing the γ-polyglutamic acid synergistic dyeing diammonium phosphate fertilizer according to claim 3, characterized in that: In the step 1, the bacterial suspension is firstly inoculated into a seed tank at a 5% inoculation amount for seed culture for 10 hours to obtain a seed solution, the temperature is 33° C., and the pH is natural; then the seed solution is inoculated into a fermentation tank at a 10% inoculation amount for culture, the culture time is not less than 48 hours, the temperature is 33° C., and the pH is 6.3±0.1~6.8±0.1; when the DO value of the cultured bacteria reaches 0.55~0.65, the γ-polyglutamic acid fermentation solution is obtained.

6. The method for preparing the γ-polyglutamic acid synergistic dyeing diammonium phosphate fertilizer according to claim 3, characterized in that: The content of γ-polyglutamic acid in the diammonium phosphate fertilizer obtained in step 3 is ≥3.5%.

7. The method for preparing the γ-polyglutamic acid synergistic dyeing diammonium phosphate fertilizer according to claim 3, characterized in that: The content of γ-polyglutamic acid in the diammonium phosphate fertilizer obtained in step 3 is ≥150 mg / Kg.

8. Use of the γ-polyglutamic acid synergistic dyeing diammonium phosphate fertilizer according to any one of claims 1 to 7 in crop planting.

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