Preparation method of arginine premix

Abstract

The invention discloses a preparation method of an arginine premix, and relates to the technical field of biology. The preparation method comprises the following steps: adjusting the pH value of arginine fermentation liquor to 3-5, and concentrating to obtain concentrated liquor; adding a carrier into the concentrated solution while stirring, and continuously stirring uniformly to obtain a mixed solution; granulating the mixed solution through a fluidized bed to obtain an arginine premix precursor; and uniformly mixing the arginine premix precursor with a moisture-proof agent to obtain the arginine premix. The preparation method has the advantages of greenness, environmental protection, low cost, continuous production and the like, and the prepared arginine premix has the advantages of high granularity, uniform particles, high moisture absorption resistance and the like.

Description

Technical Field

[0001] The invention relates to the field of biotechnology, in particular to a method for preparing an arginine premix. Background Art

[0002] L-arginine is a basic amino acid with important biochemical and physiological significance. It is an essential amino acid for newborn mammals and a conditionally essential amino acid for adult mammals. It plays an important role in the growth, development and metabolism of humans and animals. At present, L-arginine has been widely used in the pharmaceutical, food and feed industries, especially in the field of amino acid feed additives, making it the fifth largest feed additive after methionine, lysine, threonine and tryptophan.

[0003] The main production methods of L-arginine include microbial fermentation, animal hair extraction and chemical synthesis. Among them, animal hair extraction and chemical synthesis require a large amount of toxic and harmful reagents, and the production cost is high, and they have been gradually eliminated by the market. In recent years, with the development of biotechnology, strains with high L-arginine production have been developed, making microbial fermentation production of L-arginine the mainstream production method.

[0004] Most of the arginine feed additive products currently sold on the market are made by mixing 98 fine arginine with other auxiliary materials. The production cost is high and the price is expensive, which is difficult for most feed companies to afford. At the same time, due to the extremely strong water solubility of arginine, its granular products are very easy to absorb moisture, affecting the use of the product. The arginine fermentation broth obtained by microbial fermentation contains not only a high dose of arginine, but also bacterial protein, vitamins, trace elements and other various amino acids, which are all important ingredients required in compound feed. The present invention intends to obtain a low hygroscopic arginine feed additive product by improving the preparation process while rationally utilizing the effective ingredients in the fermentation broth. Summary of the invention

[0005] The purpose of the present invention is to provide a method for preparing an arginine premix to solve the problems existing in the above-mentioned prior art. The preparation method has the advantages of being green, environmentally friendly, low cost, and continuous production, and the prepared arginine premix has the advantages of high particle size, uniform particles, and strong moisture absorption resistance.

[0006] To achieve the above object, the present invention provides the following solutions:

[0007] The present invention provides a method for preparing an arginine premix, comprising the following steps:

[0008] The pH of the arginine fermentation broth is adjusted to 3-5, and concentrated to obtain a concentrated solution;

[0009] Adding the concentrated solution to the carrier while stirring, and continuing to stir evenly to obtain a mixed solution;

[0010] granulating the mixed solution in a fluidized bed to obtain an arginine premix precursor;

[0011] The arginine premix precursor and the moisture-proof agent are mixed evenly to obtain the arginine premix.

[0012] Furthermore, the pH of the arginine fermentation broth is adjusted using a sulfuric acid solution.

[0013] Furthermore, the solid content of the concentrated liquid is 30-40%.

[0014] Furthermore, the proportion of arginine in the total solids of the mixed solution is 30-35%.

[0015] Furthermore, the concentration equipment used for the concentration is a triple-effect concentrator, a quadruple-effect evaporator, a plate evaporator or an MVR evaporator.

[0016] Furthermore, the carrier includes heavy calcium carbonate and corn cob powder.

[0017] Furthermore, the mass ratio of the heavy calcium carbonate to the corn cob powder is 1:(3-4).

[0018] Furthermore, the carrier also includes magnesium silicate.

[0019] Furthermore, the mass ratio of the magnesium silicate, the corncob powder and the heavy calcium carbonate is 1:3:1.

[0020] The present invention also provides an arginine premix prepared according to the above preparation method.

[0021] The present invention discloses the following technical effects:

[0022] In view of the shortcomings of conventional feed-grade arginine preparation process, such as high cost and strong hygroscopicity of the product, the present invention provides a method for preparing an arginine premix, wherein a fermentation broth with high arginine content is obtained by fermentation, sulfuric acid is used to adjust the pH to improve the fluidity of the fermentation broth and prevent arginine degradation, the fermentation broth is concentrated to remove a large amount of water in the fermentation broth, a carrier is added to form an arginine premix mixed solution, and finally fluidized bed granulation is performed to obtain an arginine premix that meets the specifications. The preparation method of the present invention has the following advantages:

[0023] 1. The preparation method of the present invention does not require the use of a large amount of organic solvents, does not generate a large amount of organic wastewater, and the organic matter in the fermentation liquid is fully utilized without generating waste residue. The preparation method of the present invention is green and environmentally friendly, and saves the cost of treating wastewater and waste residue, and all the arginine in the fermentation liquid is utilized.

[0024] 2. The arginine premix of the present invention has the advantages of high particle size, uniform particles, strong moisture absorption resistance, etc.

[0025] 3. Each step of the preparation method of the present invention has the characteristics of continuous production, and there is no need to interrupt between the steps, which reduces labor costs, has high production efficiency and high output. DETAILED DESCRIPTION

[0026] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as limiting the present invention, but should be understood as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0027] It should be understood that the terms described in the present invention are only for describing a particular embodiment and are not intended to limit the present invention. In addition, for the numerical range in the present invention, it should be understood that each intermediate value between the upper and lower limits of the scope is also specifically disclosed. The intermediate value in any stated value or stated range, and each smaller range between any other stated value or intermediate value in the described range is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded in the scope.

[0028] Unless otherwise indicated, all technical and scientific terms used herein have the same meanings as those generally understood by those skilled in the art. Although the present invention describes only preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of a conflict with any incorporated document, the content of this specification shall prevail.

[0029] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments of the present invention description without departing from the scope or spirit of the present invention. Other embodiments derived from the present invention description will be apparent to those skilled in the art. The present invention description and examples are exemplary only.

[0030] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0031] The arginine-producing bacteria used in the present invention are Escherichia coli JA-6, which was deposited in the General Microbiology Center of China National Microbiological Culture Collection Committee on September 3, 2024, with the deposit address at No. 3, Yard No. 1, Beichen West Road, Chaoyang District, Beijing, and the deposit number is CGMCC No. 31851.

[0032] Example 1

[0033] Preparation of fermentation broth:

[0034] The activated arginine production bacteria (Escherichia coli) strains after seed bottle culture and seed tank culture are inoculated and fermented to obtain arginine fermentation liquid. The culture temperature of seed bottle culture is 37°C, the shaking speed is 220 rpm, and the culture time is 12h; the culture temperature of seed tank culture is 37°C, the pH value is 6.8, the tank pressure is 0.05MPa, the stirring speed is 200 rpm, the ventilation volume is 2L / min, and the culture time is 8h; the culture temperature of fermentation culture is 37°C, the pH value is 6.8, the tank pressure is 0.05MPa, the stirring speed is 300 rpm, the ventilation volume is 13L / min, and the culture time is 48-50h. After the fermentation is completed, the fermentation liquid is collected for use.

[0035] LB medium was used for both bottle culture and seed tank culture.

[0036] Fermentation medium: glucose 20g / L, magnesium sulfate heptahydrate 2g / L, beet molasses 6.719g / L, ammonium sulfate 8.072g / L, yeast extract 1g / L, corn steep liquor powder 6.711g / L, potassium dihydrogen phosphate 2g / L, threonine 0.75g / L, ferrous sulfate 0.02g / L, manganese sulfate 0.075g / L, biotin 0.003g / L, and the balance water.

[0037] Example 2

[0038] 1. Pretreatment and concentration of fermentation broth

[0039] Take the arginine fermentation liquid prepared in Example 1 (wherein the arginine content is 120 g / L and the solid content is 14%), and adjust the pH to 3.5 with dilute sulfuric acid (the pH can reach the same effect in the range of 3-5). Heat the fermentation liquid after pH adjustment to 65°C, keep warm for 30 minutes, and sterilize for use.

[0040] The sterilized fermentation liquid is directly concentrated by a four-effect evaporator, wherein the first effect temperature is 100° C. and the fourth effect temperature is 60° C., and a concentrated liquid with a solid content of 40% is obtained for standby use.

[0041] 2. Mixing of concentrate and carrier

[0042] Take the prepared concentrated solution, add a carrier mixture of heavy calcium carbonate and corn cob powder (mass ratio 1:3) while stirring until the arginine accounts for 30% of the total solids, continue stirring until the feed liquid is evenly mixed, and obtain a mixed solution for use.

[0043] 3. Fluidized bed granulation

[0044] The prepared mixed solution was taken and pumped to a fluidized bed granulator with the hot air inlet temperature being 180° C. and the outlet temperature being 100° C. to prepare an arginine premix precursor.

[0045] 4. Mixed moisture-proof agent

[0046] Take the prepared arginine premix precursor, add silicon dioxide (final content is 2.5‰), mix thoroughly and evenly, and obtain the final product arginine premix.

[0047] Example 3

[0048] 1. Pretreatment and concentration of fermentation broth

[0049] Take the arginine fermentation liquid prepared in Example 1, and adjust the pH to 3.5 with dilute sulfuric acid (the pH can reach the same effect within the range of 3.5±0.5). Heat the fermentation liquid after pH adjustment to 65°C, keep warm for 30 minutes, and sterilize for later use.

[0050] The sterilized fermentation liquid is directly concentrated by a four-effect evaporator, wherein the first effect temperature is 100° C. and the fourth effect temperature is 60° C., and a concentrated liquid with a solid content of 30% is obtained for standby use.

[0051] 2. Mixing of concentrate and carrier

[0052] Take the prepared concentrated solution, add a carrier mixture of magnesium silicate, corn cob powder and heavy calcium carbonate (mass ratio 1:3:1) while stirring until arginine accounts for 32% of the total solids, continue stirring until the feed liquid is evenly mixed, and obtain a mixed solution for use.

[0053] 3. Fluidized bed granulation

[0054] The prepared mixed solution was taken and pumped to a fluidized bed granulator with the hot air inlet temperature being 180° C. and the outlet temperature being 100° C. to prepare an arginine premix precursor.

[0055] 4. Mixed moisture-proof agent

[0056] Take the prepared arginine premix precursor, add silicon dioxide (final content is 5‰), mix thoroughly and evenly, and obtain the final product arginine premix.

[0057] Example 4

[0058] 1. Pretreatment and concentration of fermentation broth

[0059] Take the arginine fermentation liquid prepared in Example 1, and adjust the pH to 3.5 with dilute sulfuric acid (the pH can reach the same effect within the range of 3.5±0.5). Heat the fermentation liquid after pH adjustment to 65°C, keep warm for 30 minutes, and sterilize for later use.

[0060] The sterilized fermentation liquid is directly concentrated by a four-effect evaporator, wherein the first effect temperature is 100° C. and the fourth effect temperature is 60° C., and a concentrated liquid with a solid content of 35% is obtained for standby use.

[0061] 2. Mixing of concentrate and carrier

[0062] Take the prepared concentrated solution, add a carrier mixture of heavy calcium carbonate and corn cob powder (mass ratio 1:4) while stirring until the arginine accounts for 35% of the total solids, continue stirring until the feed liquid is evenly mixed, and obtain a mixed solution for use.

[0063] 3. Fluidized bed granulation

[0064] The prepared mixed solution was taken and pumped to a fluidized bed granulator with the hot air inlet temperature being 180° C. and the outlet temperature being 100° C. to prepare an arginine premix precursor.

[0065] 4. Mixed moisture-proof agent

[0066] Take the prepared arginine premix precursor, add silicon dioxide (final content is 5‰), mix thoroughly and evenly, and obtain the final product arginine premix.

[0067] Comparative Example 1

[0068] The same as Example 2, except that the pH of the arginine fermentation broth is not adjusted, and the concentration treatment is directly performed, and the addition amounts of the carrier mixture and the concentrated solution in step 2 are the same as those in Example 2.

[0069] Compared with Example 2, the arginine content of the arginine premix prepared by the method of this comparative example is reduced from 30% to 25%. At the same time, the uniformity of the arginine concentrate of this comparative example is reduced, the fluidity of the material is poor, which is not conducive to the atomization during the subsequent fluidized bed granulation, and the uniformity and quality stability of the prepared arginine premix are reduced.

[0070] Comparative Example 2

[0071] Same as Example 2, except that step 4 is not performed.

[0072] This comparative example successfully prepared an arginine premix that met the specifications, but because no moisture-proofing agent was added during the preparation process, its moisture-proof ability failed to meet expectations.

[0073] Comparative Example 3

[0074] Same as Example 2, except that the carrier mixture is replaced by heavy calcium carbonate.

[0075] Since corn cob powder was not added as a shaping carrier, the mesh size of the particles obtained in this comparative example was smaller, and step 4 took longer, resulting in a darker product color and a lower product content than expected.

[0076] Comparative Example 4

[0077] Same as Example 2, except that the carrier mixture is replaced with corncob powder.

[0078] Since corn cob powder was used as the carrier, the agglomeration phenomenon was obvious during the granulation process in this comparative example. In addition, due to the lower specific gravity of corn cob powder, a large amount of corn cob powder rose during the granulation process, and the product content was higher than expected.

[0079] Comparative Example 5

[0080] The same as Example 2, except that the solid content of the concentrated solution prepared in step 1 is 60%.

[0081] Since the concentration ratio is too high, the concentrated liquid of this comparative example has a large viscosity, so that step 3 cannot be carried out smoothly. At the same time, the mixed material is dough-like and has no fluidity, so the subsequent step 4 cannot be carried out.

[0082] Comparative Example 6

[0083] The same as Example 2, except that the solid content of the concentrated solution prepared in step 1 is 20%.

[0084] Since the concentration ratio is too low, step 4 takes too long and the water content of the product is too high to meet the preset product standards.

[0085] The hygroscopic parameters of Examples 2-4, Comparative Examples 1-4 and similar products purchased on the market were compared under the conditions of 20° C. and 65% humidity. The results are shown in Table 1.

[0086] Specific moisture absorption rate = Δm / (m 0 ×t);

[0087] Where Δm is the change in sample mass; m 0 is the initial sample mass; t is the measurement interval.

[0088] The maximum specific moisture absorption rate is the maximum value of the specific moisture absorption rate during the measurement process.

[0089] Saturated moisture absorption rate = Δm B / m 0 ×100%;

[0090] In the formula, Δm B is the change in sample mass when the sample reaches saturation due to moisture absorption, m 0 is the initial sample mass.

[0091] Table 1 Comparison of hygroscopic parameters of Examples 2-4, Comparative Examples 1-4 and similar products purchased on the market

[0092]

[0093] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A method for preparing an arginine premix, characterized in that: The following steps are involved: The pH of the arginine fermentation broth is adjusted to 3-5, and concentrated to obtain a concentrated solution; Adding the concentrated solution to the carrier while stirring, and continuing to stir evenly to obtain a mixed solution; granulating the mixed solution in a fluidized bed to obtain an arginine premix precursor; The arginine premix precursor and the moisture-proof agent are mixed evenly to obtain the arginine premix.

2. The preparation method according to claim 1, characterized in that: The pH of the arginine fermentation broth was adjusted using a sulfuric acid solution.

3. The preparation method according to claim 1, characterized in that: The solid content of the concentrated liquid is 30-40%.

4. The preparation method according to claim 1, characterized in that: Arginine accounts for 30-35% of the total solids in the mixed solution.

5. The preparation method according to claim 1, characterized in that: The concentration equipment used in the concentration is a triple-effect concentrator, a quadruple-effect evaporator, a plate evaporator or an MVR evaporator.

6. The preparation method according to claim 1, characterized in that: The carrier includes heavy calcium carbonate and corn cob powder.

7. The preparation method according to claim 6, characterized in that: The mass ratio of the heavy calcium carbonate to the corn cob powder is 1:(3-4).

8. The preparation method according to claim 6, characterized in that: The carrier also includes magnesium silicate.

9. The preparation method according to claim 8, characterized in that: The mass ratio of the magnesium silicate, the corncob powder and the heavy calcium carbonate is 1:3:

1.

10. An arginine premix prepared according to the preparation method according to any one of claims 1 to 9.

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