CN115259958A - Microbial granular fertilizer with polyglutamic acid adsorbed by charcoal and preparation method thereof - Google Patents

Abstract

The invention discloses a microbial granular fertilizer for adsorbing polyglutamic acid by biochar and a preparation method thereof. The fertilizer comprises a certain proportion of biochar, polyglutamic acid fermentation broth, microbial bacteria, urea, monoammonium phosphate, potassium chloride, Humic acid, auxiliary materials, etc.; the preparation method is as follows: using straw as raw material to prepare biochar; inoculating activated polyglutamic acid-producing Bacillus subtilis for fermentation in a liquid fermentation medium, and adding biochar during the fermentation process; fermentation; After the end, add urea, monoammonium phosphate, potassium chloride, humic acid, auxiliary materials, etc. in a certain proportion, mix well, granulate with a swing granulator, and dry at low temperature to obtain granular fertilizer. The biochar adsorbed polyglutamic acid microbial granular fertilizer can effectively promote the growth and development of crops, take root and strengthen seedlings, and significantly improve the drought resistance and fertilizer utilization efficiency of crops.

Description

A kind of microbial granular fertilizer with biochar adsorption of polyglutamic acid and preparation method thereof

technical field

The invention belongs to the technical field of fertilizers, and in particular relates to a microbial granular fertilizer for absorbing polyglutamic acid by biochar and a preparation method thereof.

Background technique

The production and consumption of nitrogen and phosphorus fertilizers in my country rank first in the world, but their utilization rates are very low. Among them, the utilization efficiency of nitrogen fertilizers is only 30% to 50%. Lost in soluble or volatile form. The utilization rate of phosphate fertilizer is only 10% to 25%. In recent years, the problem of excessive application of nitrogen and phosphate fertilizer has become more and more serious, the loss rate has become larger, and the residual fertilizer has brought serious pollution load to the environment. Therefore, to solve the problem of low utilization rate of nitrogen and phosphorus fertilizers and to explore the application of synergists to agriculture has become a focus of attention.

γ-polyglutamic acid is a pure natural biopolymer substance formed by the polymerization of glutamic acid monomers through γ-amide bonds. Its main chain contains a large number of free carboxyl groups, making it have the characteristics of general anionic surfactants , can bond with NH4 ⁺ , PO ₄ ³⁺ , K+, Ca ²⁺ , Mg ²⁺ and other cations in fertilizers to form a stable γ-polyglutamate solution, which has the functions of adsorption, integration and storage. Store unused nutrients in the early stage of crop growth and release them slowly in the later stage, thereby increasing the utilization rate of NH ⁴⁺ , K ⁺ , ^Ca 2+ , and Mg ²⁺ , reducing fertility waste and effectively improving fertilizer efficiency. On the other hand, γ-polyglutamic acid can also reduce the fixation of phosphorus fertilizer in the soil, increase the content of available phosphorus, promote crop growth, improve plant stress resistance, and enhance product quality. Therefore, the characteristics of γ-polyglutamic acid make it a synergist for new biological fertilizers and green environmental protection fertilizers that replace traditional chemical fertilizers.

Biochar is a porous material produced by decomposing agricultural and forestry waste, sawdust and other biomass materials under high temperature and oxygen-limited conditions. It contains extremely rich carbon and has strong adsorption capacity. After absorbing γ-polyglutamic acid, it can reduce γ- The degradation rate of polyglutamic acid, after being applied to the soil, can be further improved to improve the water retention, fertilizer retention performance and fertilizer efficiency of the soil.

Contents of the invention

The purpose of the invention is to overcome the deficiencies in the prior art, to provide a kind of preparation method that can improve fertilizer utilization rate, improve soil fertility, improve soil, and promote the microbial granular fertilizer of charcoal-adsorbed polyglutamic acid containing polyglutamic acid of plant growth.

In order to achieve the above object, the present invention provides the following technical scheme: a microbial granular fertilizer for biochar adsorption of polyglutamic acid, comprising the following raw materials in parts by weight: 15-20 parts of urea, 10-20 parts of monoammonium phosphate, chlorinated Potassium 15-20 parts, biochar 10-15 parts, polyglutamic acid 0.1-3 parts, Bacillus subtilis live bacteria 100 million/g, humic acid 5-10 parts, auxiliary materials 30-50 parts.

Preferably, the strain used for fermentation is Bacillus subtilis capable of producing γ-polyglutamic acid.

Preferably, the polyglutamic acid is a fermentation broth containing polyglutamic acid produced by fermentation of Bacillus subtilis in a liquid fermentation medium.

The content of polyglutamic acid in it is 4%; the strain used for fermentation is classified as Bacillus Subtilis SCP0101-1, which has been preserved in the China General Microorganism Culture Collection Center (CGMCC), and the address is Chaoyang District, Beijing No. 3, No. 1 Yard, Beichen West Road, strain preservation number CGMCC24347, preservation date is January 19, 2022;

Another technical solution provided in this scheme is to provide a preparation method of microbial granular fertilizer that absorbs polyglutamic acid by biochar, and the preparation process of described microbial granular fertilizer comprises the following steps:

(1) Preparation of biochar: put the dried straw in a muffle furnace, heat up to 400-500°C under anaerobic conditions, pyrolyze it for 90-180min, cool to room temperature, take out the carbonized product, pulverize and sieve, Preparation of biochar;

(2) Preparation of biochar-adsorbed polyglutamic acid fermentation broth: Inoculate polyglutamic acid-producing Bacillus subtilis on a nutrient-rich solid seed medium, culture at 37°C for 18-24 hours, and prepare strains , inoculate in liquid activated culture medium, shake culture at 37°C for 18-24 hours to obtain activated bacterial liquid, put the activated bacterial liquid into a fermenter equipped with liquid fermentation medium, culture with shaking at 37°C for 36 hours, add a certain A certain amount of biochar adsorbs polyglutamic acid, and continues to cultivate for 12 hours to prepare a fermentation broth for biochar adsorbing polyglutamic acid;

(3) Granulation and molding of granular fertilizers: after fermentation, add urea, monoammonium phosphate, potassium chloride, humic acid, auxiliary materials, etc. in proportion, mix well, granulate with a swing machine, and dry at low temperature to obtain granular fertilizer.

Preferably, the biochar is prepared from one of corn stalks, pepper stalks, sunflower stalks or wheat stalks.

Preferably, the auxiliary material is one or more of soluble starch, bentonite, sodium silicate solution, talcum powder, β-cyclodextrin, added powder, and decomposed cow dung.

Preferably, the solid seed culture medium components described in the step (2) are 1% peptone, 0.5% yeast powder, 0.5% sodium chloride, 2% agar powder, pH7.0;

The activated culture medium does not contain agar powder, and the remaining components are the same as the solid seed medium. The components of the liquid fermentation medium are 90g/L of sucrose, 10g/L of yeast powder, 50g/L of monosodium glutamate, and 5g of ammonium chloride. /L, urea 6g/L, dipotassium hydrogen phosphate 1.5g/L, potassium dihydrogen phosphate 0.5g/L, magnesium sulfate 0.208g/L, calcium chloride 0.01g/L, pH 6.8-7.2.

Preferably, for the granulation and molding of the granular fertilizer described in the step (3), according to the specific content of polyglutamic acid in the fermentation broth, urea, monoammonium phosphate, potassium chloride, humic acid, and auxiliary materials are added in proportion , deionized water, etc. Finally, the content of polyglutamic acid is between 0.1% and 3%, and the water content of the mixture is between 20% and 35%.

Compared with the prior art, the beneficial effects of the present invention are: the biochar-adsorbed polyglutamic acid microbial granular fertilizer and the preparation method thereof, γ-polyglutamic acid has improved soil structure, and is effective for NH ⁴⁺ , PO ₄ ³⁺ and K+ have the function of adsorption integration and storage, improve the utilization rate of NH ⁴⁺ , K ⁺ and Ca ²⁺ , Mg ²⁺ , reduce the waste of fertility and effectively improve fertilizer efficiency. In particular, it can also reduce the fixation of phosphorus fertilizer in the soil, increase the content of available phosphorus, and promote the effective utilization of phosphorus fertilizer. Biochar is a porous material with rich carbon content and strong adsorption capacity, which can effectively adsorb γ-polyglutamic acid and delay the degradation time of γ-polyglutamic acid. Fertilizer performance.

The present invention is directly based on the fermentation liquid containing polyglutamic acid, mixed with various components, the process flow is simple, no special extraction of polyglutamic acid is needed, and fertilizer granules are prepared, and the bacterial content of Bacillus subtilis reaches 200 million/g, which is effective. It is beneficial to reduce pathogen invasion and reproduction opportunities, so as to achieve the purpose of reducing crop diseases.

Description of drawings

Fig. 1 is the schematic diagram of the loose porous structure presented by the biochar prepared by the present invention under a SEM scanning electron microscope magnified 500 times;

Fig. 2 is a schematic diagram of the loose porous structure of the biochar prepared by the present invention under a SEM scanning electron microscope magnified 1500 times.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

Embodiment one:

A microbial granular fertilizer containing carbon-adsorbed polyglutamic acid and a preparation method thereof, specifically comprising the following steps:

(1) Strain cultivation: Inoculate polyglutamic acid-producing Bacillus subtilis on LB solid seed medium and culture at 37°C for 24 hours to prepare the strain;

(2) Preparation of activated bacterial liquid: Bacillus subtilis colonies were picked, inoculated into liquid activated culture liquid, and shaken at 37°C for 24 hours to obtain activated bacterial liquid;

(3) Fermentation culture: get the activated bacterium liquid, according to the inoculum size of 5%, insert in the fermenter that liquid fermentation medium is housed, carry out fermentation culture according to the following conditions:

Dissolved oxygen: air flow 0.5vvmm, dissolved oxygen 36%; stirring speed 450r/m;

Temperature: 37°C;

pH value: Use filter-sterilized ammonia water to control the pH to 6.8;

Tank pressure: 0.04MPa;

32 hours before the fermentation process, according to the consumption of sucrose and glutamic acid, supplement the content of sucrose and glutamic acid so that the concentration is not lower than 10g/L. After 32 hours of fermentation, biochar was added in a certain proportion to absorb polyglutamic acid in the fermentation broth, and after 16 hours of continuous cultivation, a fermentation broth in which biochar adsorbed polyglutamic acid was finally prepared.

(4) Granulation molding of granular fertilizer: in the fermentation liquid of biochar adsorption polyglutamic acid prepared above, add 15 parts of urea, 15 parts of monoammonium phosphate, 15 parts of potassium chloride, humic Mix 5 parts of acid, 20 parts of bentonite, 20 parts of soluble starch, and 10 parts of decomposed cow dung, pour them into a swing machine in batches for granulation; dry at low temperature to obtain chicken bouillon columnar granular fertilizer.

Embodiment two:

A microbial granular fertilizer containing carbon-adsorbed polyglutamic acid and a preparation method thereof, specifically comprising the following steps:

(1) Strain cultivation: Inoculate polyglutamic acid-producing Bacillus subtilis on LB solid seed medium and culture at 37°C for 24 hours to prepare the strain;

(2) Preparation of activated bacterial liquid: Bacillus subtilis colonies were picked, inoculated into liquid activated culture liquid, and shaken at 37°C for 24 hours to obtain activated bacterial liquid;

(3) Fermentation culture: get the activated bacterium liquid, according to the inoculum size of 5%, insert in the fermenter that liquid fermentation medium is housed, carry out fermentation culture according to the following conditions:

Dissolved oxygen: air flow 0.6vvmm, dissolved oxygen 35%; stirring speed 400r/m;

Temperature: 37°C;

pH value: Use filter-sterilized ammonia water to control the pH to 6.8;

Tank pressure: 0.04MPa;

32 hours before the fermentation process, according to the consumption of sucrose and glutamic acid, supplement the content of sucrose and glutamic acid so that the concentration is not lower than 10g/L. After 32 hours of fermentation, biochar was added in a certain proportion to absorb polyglutamic acid in the fermentation broth, and after 16 hours of continuous cultivation, a fermentation broth in which biochar adsorbed polyglutamic acid was finally prepared.

(4) Granulation and molding of granular fertilizer: In the fermentation liquid prepared above by biochar adsorption of polyglutamic acid, add 20 parts of urea, 15 parts of monoammonium phosphate, 15 parts of potassium chloride, humic acid 10 parts, 10 parts of soluble starch, 20 parts of bentonite, 5 parts of sodium silicate solution, 10 parts of talcum powder, 5 parts of β-cyclodextrin, etc., mix well, pour into the shaker in batches for granulation; dry at low temperature, The columnar granular fertilizer of chicken bouillon is obtained.

Embodiment three:

A microbial granular fertilizer containing carbon-adsorbed polyglutamic acid and a preparation method thereof, specifically comprising the following steps:

(1) Strain cultivation: Inoculate polyglutamic acid-producing Bacillus subtilis on LB solid seed medium and culture at 37°C for 24 hours to prepare the strain;

(2) Preparation of activated bacterial liquid: Bacillus subtilis colonies were picked, inoculated into liquid activated culture liquid, and shaken at 37°C for 24 hours to obtain activated bacterial liquid;

(3) Fermentation culture: get the activated bacterium liquid, according to the inoculum size of 5%, insert in the fermenter that liquid fermentation medium is housed, carry out fermentation culture according to the following conditions:

Dissolved oxygen: air flow 0.6vvmm, dissolved oxygen 35%; stirring speed 400r/m;

Temperature: 37°C;

pH value: Use filter-sterilized ammonia water to control the pH to 6.8;

Tank pressure: 0.04MPa;

32 hours before the fermentation process, according to the consumption of sucrose and glutamic acid, supplement the content of sucrose and glutamic acid so that the concentration is not lower than 10g/L. After 32 hours of fermentation, biochar was added in a certain proportion to absorb polyglutamic acid in the fermentation broth, and after 16 hours of continuous cultivation, a fermentation broth in which biochar adsorbed polyglutamic acid was finally prepared.

(4) Granulation molding of granular fertilizer: in the fermentation liquid of biochar adsorption polyglutamic acid prepared above, add 12 parts of urea, 20 parts of monoammonium phosphate, 20 parts of potassium chloride, humic acid 5 parts, 15 parts of bentonite, 15 parts of talcum powder, 5 parts of β-cyclodextrin, 5 parts of Jiayi powder, 10 parts of decomposed cow dung, mix well, pour into the shaker in batches for granulation; dry at low temperature to get Chicken essence columnar granular fertilizer.

Embodiment four:

A microbial granular fertilizer containing carbon-adsorbed polyglutamic acid and a preparation method thereof, specifically comprising the following steps:

(1) Strain cultivation: Inoculate polyglutamic acid-producing Bacillus subtilis on LB solid seed medium and culture at 37°C for 24 hours to prepare the strain;

(2) Preparation of activated bacterial liquid: Bacillus subtilis colonies were picked, inoculated into liquid activated culture liquid, and shaken at 37°C for 24 hours to obtain activated bacterial liquid;

(3) Fermentation culture: get the activated bacterium liquid, according to the inoculum size of 5%, insert in the fermenter that liquid fermentation medium is housed, carry out fermentation culture according to the following conditions:

Dissolved oxygen: air flow 0.6vvmm, dissolved oxygen 35%; stirring speed 400r/m;

Temperature: 37°C;

pH value: Use filter-sterilized ammonia water to control the pH to 7.2;

Tank pressure: 0.04MPa;

32 hours before the fermentation process, according to the consumption of sucrose and glutamic acid, supplement the content of sucrose and glutamic acid so that the concentration is not lower than 10g/L. After 32 hours of fermentation, biochar was added in a certain proportion to absorb polyglutamic acid in the fermentation broth, and after 16 hours of continuous cultivation, a fermentation broth in which biochar adsorbed polyglutamic acid was finally prepared.

(4) Granulation and molding of granular fertilizer: in the fermentation liquid of biochar adsorption polyglutamic acid prepared above, add 12 parts of urea, 20 parts of monoammonium phosphate, 18 parts of potassium chloride, humic acid 10 parts of starch, 10 parts of soluble starch, 10 parts of bentonite, 10 parts of talcum powder, 10 parts of decomposed cow dung, etc., mix well, pour into the swing machine in batches for granulation; dry at low temperature to obtain granular fertilizer.

Fertilizer experiment

Taking small rapeseed as the experimental object, the pot planting experiment was carried out. Three treatments were set up in the experiment, treatment 1 did not fertilize, treatment 2 applied ordinary compound fertilizer, and treatment 3 applied the microbial granular fertilizer of biochar-adsorbed polyglutamic acid of the present invention, and the amount of fertilizer applied per kilogram of soil was: 2g. Comparing the amount of nitrogen, phosphorus, and potassium absorbed by the plants after harvesting rapeseed with the application amount of nitrogen, phosphorus, and potassium fertilizers before sowing, and calculating the utilization rate of fertilizers, the experimental results are as follows:

Table 1 Analysis of nitrogen, phosphorus, and potassium utilization rates of microbial granular fertilizers adsorbed with polyglutamic acid by biochar

As can be seen from Table 1, the microbial granular fertilizer of biochar adsorption polyglutamic acid prepared by the present invention, its nitrogen, phosphorus, potassium utilization rate have improved respectively 46.3%, 36.3%, 23.2%, so the compound fertilizer that the present invention obtains can effectively Improve the utilization rate of fertilizer.

Table 2 Effects of different treatments on fresh weight, dry weight, plant height and chlorophyll content of small rapeseed

deal with Fresh weight per plant (g) Single plant dry weight (g) Plant height (mm) Chlorophyll content (SPAD) processing 1 16.3±2.5 1.4±0.21 45±4 37.5±0.24 processing 2 26.7±3.4 3.2±0.25 48±3 41.2±0.15 processing 3 32.1±3.6 3.8±0.30 58±3 47.7±0.25

The experimental group treated with the microbial granular fertilizer of biochar adsorption polyglutamic acid prepared by the present invention, fresh weight, dry weight, plant height and leaf element content are all higher than the unfertilized control group and the experimental group using common compound fertilizer . It shows that the application of the microbial granular fertilizer prepared by the present invention with biochar-adsorbed polyglutamic acid can significantly increase the fresh weight, dry weight, plant height and chlorophyll content of crops, and has the effect of promoting the growth and development of crops.

The content that is not described in detail in this specification belongs to the prior art known to those skilled in the art. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still implement the foregoing Modifications to the technical solutions recorded in the examples, or equivalent replacements for some of the technical features, within the spirit and principles of the present invention, any modifications, equivalent replacements, improvements, etc., shall be included in the scope of protection of the present invention within.

Claims (8)

1. The microbial granular fertilizer with the polyglutamic acid adsorbed by the biochar is characterized by comprising the following raw materials in parts by weight: 15-20 parts of urea, 10-20 parts of monoammonium phosphate, 15-20 parts of potassium chloride, 10-15 parts of charcoal, 0.1-3 parts of polyglutamic acid, 1 hundred million/g of live bacillus subtilis, 5-10 parts of humic acid and 30-50 parts of auxiliary materials.

2. The microbial granular fertilizer with polyglutamic acid adsorbed by biochar as claimed in claim 1, wherein: the strain for fermentation is bacillus subtilis capable of producing gamma-polyglutamic acid.

3. The microbial granular fertilizer with polyglutamic acid adsorbed by biochar as claimed in claim 1, wherein: the polyglutamic acid is fermentation liquor containing the polyglutamic acid, which is generated by fermenting the bacillus subtilis in a liquid fermentation culture medium.

4. A method for preparing the microorganism granular fertilizer with the biological carbon adsorbing polyglutamic acid as the claim 1, which is characterized in that: the preparation process of the microbial granular fertilizer comprises the following steps:

(1) Preparing the biochar: placing the dried straw in a muffle furnace, heating to 400-500 ℃ under anaerobic condition, pyrolyzing for 90-180min, cooling to normal temperature, taking out carbide, crushing, and sieving to obtain biochar;

(2) Preparing fermentation liquor for adsorbing polyglutamic acid by using charcoal: inoculating bacillus subtilis producing polyglutamic acid on a solid seed culture medium rich in nutrition, culturing at 37 ℃ for 18-24 hours to prepare a strain, inoculating the strain in a liquid activated culture solution, performing oscillation culture at 37 ℃ for 18-24 hours to obtain an activated bacterial solution, inoculating the activated bacterial solution into a fermentation tank filled with a liquid fermentation culture medium, performing oscillation culture at 37 ℃ for 36 hours, adding a certain amount of charcoal, adsorbing the polyglutamic acid, and continuously culturing for 12 hours to prepare a fermentation liquid of the charcoal adsorbing the polyglutamic acid;

(3) Granulating and molding the granular fertilizer: after fermentation, adding urea, monoammonium phosphate, potassium chloride, humic acid, auxiliary materials and the like according to a certain proportion, uniformly mixing, granulating by using a swing machine, and drying at a low temperature to obtain the granular fertilizer.

5. The method for preparing the microbial granular fertilizer with polyglutamic acid adsorbed by biochar as claimed in claim 4, wherein the biochar is used for preparing the microbial granular fertilizer with polyglutamic acid adsorbed by the biochar as follows: the biochar is prepared from one of corn straw, pepper straw, sunflower straw or wheat straw.

6. The method for preparing the microbial granular fertilizer with polyglutamic acid adsorbed by biochar as claimed in claim 4, wherein the biochar is used for preparing the microbial granular fertilizer with polyglutamic acid adsorbed by the biochar as follows: the auxiliary materials are one or more of soluble starch, bentonite, sodium silicate solution, talcum powder, beta-cyclodextrin, benefical powder and decomposed cow dung.

7. The method for preparing the microbial granular fertilizer with polyglutamic acid adsorbed by biochar as claimed in claim 4, wherein the biochar is used for preparing the microbial granular fertilizer with polyglutamic acid adsorbed by the biochar as follows: the components of the solid seed culture medium in the step (2) are 1% of peptone, 0.5% of yeast powder, 0.5% of sodium chloride, 2% of agar powder and pH7.0;

the activated culture solution does not contain agar powder, the rest components are the same as those of a solid seed culture medium, and the components of the liquid fermentation culture medium are 90g/L of sucrose, 10g/L of yeast powder, 50g/L of monosodium glutamate, 5g/L of ammonium chloride, 6g/L of urea, 1.5g/L of dipotassium hydrogen phosphate, 0.5g/L of monopotassium phosphate, 0.208g/L of magnesium sulfate, 0.01g/L of calcium chloride and the pH value of the activated culture solution is 6.8-7.2.

8. The method for preparing the microbial granular fertilizer with polyglutamic acid adsorbed by biochar according to claim 4, wherein the biochar is characterized in that: and (3) granulating and forming the granular fertilizer, namely adding urea, monoammonium phosphate, potassium chloride, humic acid, auxiliary materials, deionized water and the like according to the specific content of the polyglutamic acid in the fermentation liquor in proportion to ensure that the content of the polyglutamic acid is between 0.1 and 3 percent and the water content of the mixture is between 20 and 35 percent.

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