A copper N-hydroxymethyl glycine antibacterial agent

Abstract

The application relates to the field of agricultural fungicides, in particular to a preparation method and application of a copper N-hydroxymethyl glycine antibacterial agent. The effective component of the fungicide is copper N-hydroxymethyl glycine, and the antibacterial agent is prepared into an aqueous agent according to the physical and chemical properties of the effective component. In the copper N-hydroxymethyl glycine antibacterial agent, copper ions have bacteriostatic activity, N-hydroxymethyl glycine can enhance the bactericidal performance of copper ions, and can also release formaldehyde, and under the dual bactericidal action, effects are achieved on various bacterial diseases and part of fungal diseases. The application has the characteristics of low residue, small pollution, remarkable bacteriostatic effect and good biocompatibility, and has a very broad application prospect.

Description

Technical Field

[0001] This invention belongs to the field of agricultural antibacterial agents, specifically relating to a preparation method and application of an N-hydroxymethylglycine copper antibacterial agent. Background Technology

[0002] Glycine, also known as aminoacetic acid, is a non-essential amino acid with the chemical formula C2H5NO2. It is one of the simplest amino acids, a white to off-white crystalline powder, odorless and non-toxic, readily soluble in water, and practically insoluble in ethanol or ether. Glycine is widely used in the pharmaceutical industry, biochemical experiments, and organic synthesis.

[0003] Sodium N-hydroxymethylglycinate, with the molecular formula C3H6NNaO3 and CAS number 70161-44-3, possesses strong antibacterial and preservative properties. It can effectively inhibit the growth and reproduction of microorganisms such as bacteria, molds, and yeasts, thereby extending the shelf life of products. Sodium N-hydroxymethylglycinate is widely used in various products including personal care products, cosmetics, and detergents.

[0004] Copper preparations have long played a vital role in the field of agricultural antibacterial agents. As early as 1807, B. Prevost discovered the antibacterial activity of copper sulfate, but it wasn't until 1885 that it was used to protect plant leaves from disease. In 1882, Millarder A. discovered Bordeaux mixture, a solution of copper sulfate and lime water, which also possessed antibacterial activity and was safer than copper sulfate. Subsequently, many copper-containing antibacterial agents emerged, and the antibacterial function of copper ions was widely applied. In 2008, copper was officially recognized as a metallic antibacterial agent by the U.S. Environmental Protection Agency.

[0005] The antibacterial effect of copper ions is mainly due to their ability to enter pathogen cells and react with groups such as -SH, -N2H, -COOH, and -OH in fungal or bacterial proteins, causing protein denaturation and thus inhibiting metabolism, leading to pathogen death. Copper ions can also disrupt enzymes in cells, preventing normal metabolic processes in pathogens. Furthermore, copper ions can damage the cell membrane of pathogens, causing cell contents to leak out and resulting in cell death. Copper ions can also inhibit spore germination and hyphal development, preventing the spread of subsequent diseases. Because copper ions possess multiple bactericidal mechanisms and are unlikely to induce resistance with long-term use, copper-based preparations have remained in use to this day.

[0006] Currently, there are no reports on the preparation of N-hydroxymethylglycine copper antibacterial agents or their application in agriculture. Summary of the Invention

[0007] The purpose of this invention is to prepare and synthesize an N-hydroxymethylglycine copper antibacterial agent with a broad antibacterial spectrum, high safety and reliability, and in line with the direction of green and environmentally friendly development. The ligand of this invention can enhance the antibacterial properties of copper ions. Experiments have demonstrated that this invention has significant antibacterial effects against plant pathogens such as gray mold of leeks, white mold of celery, and wilt of strawberries. This invention features low residue, low pollution, significant antibacterial effect, and good biocompatibility, and has a very broad application prospect.

[0008] The technical solution adopted in this invention is as follows: the effective component of the antibacterial agent is N-hydroxymethylglycine copper, which is used to prevent and control various bacterial diseases and some fungal diseases of rice, melons, vegetables, fruits and vegetables, such as leaf blight, canker, and downy mildew.

[0009] The antibacterial agent of the present invention may be in the form of an aqueous solution, a soluble powder, or a soluble liquid.

[0010] Preferably, the antibacterial agent of the present invention is specifically a water suspension.

[0011] The formulation of the N-hydroxymethylglycine copper aqueous suspension of the present invention is composed of the following raw materials in the indicated mass ratios: N-hydroxymethylglycine copper 0.1% to 50%, wetting and dispersing agent 0.1% to 10%, thickener 0.1% to 5%, antifreeze agent 0.1% to 10%, defoamer 0.1% to 5%, and the remainder being water;

[0012] In the aqueous suspension of the present invention, the dispersant is one or more of sodium polynaphthalene sulfonate, sodium lignin sulfonate, and sodium polycarboxylate; the thickener is one or more of polyacrylate, methylcellulose, hydroxyethylcellulose, and hydroxypropyl methylcellulose; the antifreeze is one or more of ethylene glycol, propylene glycol, and glycerol; and the defoamer is one or more of organosilicon defoamers and polyether-modified organosilicon defoamers.

[0013] Preferably, the formulation of the N-hydroxymethylglycine copper aqueous suspension by weight is as follows: 30% N-hydroxymethylglycine copper, 7% sodium polynaphthalene sulfonate, 0.4% hydroxypropyl methylcellulose, 5% glycerol, 0.3% polyether-modified silicone defoamer, and the balance being water.

[0014] The preparation steps of the N-hydroxymethylglycine copper antibacterial agent of the present invention are as follows:

[0015] (1) Preparation of N-hydroxymethylglycine copper: 12.7 kg of N-hydroxymethylglycine sodium and 10.0 kg of copper acetate monohydrate were added to the reaction vessel, 100 kg of distilled water was added, and the mixture was heated at 60 °C and stirred continuously for 3 h. Then it was cooled to room temperature (25 °C) to crystallize, filtered, washed with a small amount of water, and dried to obtain 16.3 kg of N-hydroxymethylglycine copper.

[0016] (2) Preparation of 30% N-hydroxymethylglycine copper aqueous suspension: By weight, 30% N-hydroxymethylglycine copper, 7% sodium polynaphthalene sulfonate, 0.4% hydroxypropyl methylcellulose, 5% glycerol, and 0.3% polyether modified silicone defoamer are mixed, with the remainder being water. The above materials are added to an open bottle and subjected to high shear to refine and homogenize them, thus obtaining N-hydroxymethylglycine copper aqueous suspension.

[0017] 30% N-hydroxymethylglycine copper aqueous suspension can prevent and control various bacterial diseases and some fungal diseases of rice, melons, vegetables, fruits and vegetables, such as leaf blight, canker, and downy mildew. The antibacterial agent can be applied by watering, spraying, or misting.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] The N-hydroxymethylglycine copper antibacterial agent of this invention utilizes copper ions to exhibit antibacterial activity. N-hydroxymethylglycine enhances the bactericidal properties of copper ions and also releases formaldehyde. This dual bactericidal action is effective against various bacterial diseases and some fungal diseases. This invention features low residue, minimal pollution, significant antibacterial effect, and good biocompatibility, making it a promising candidate for widespread application.

[0020] Attached image:

[0021] Figure 1 Infrared spectrum of N-hydroxymethylglycine copper;

[0022] Figure 2 : Results of indoor virulence testing of gray mold in leeks;

[0023] Figure 3 : Results of indoor virulence assay for celery white mold pathogen;

[0024] Figure 4 Figure: Results of indoor virulence determination of strawberry wilt pathogen. Detailed Implementation

[0025] The present invention will be further explained and illustrated below with reference to specific embodiments:

[0026] "kg" represents the weight unit "kilogram"; "h" represents the time unit "hour"; "℃" represents the temperature unit "degrees Celsius"; "mm" represents the length unit "millimeter"; the "N-hydroxymethylglycine sodium" was purchased from "Shanghai Yuanye Biotechnology Co., Ltd."; the "copper acetate monohydrate" was purchased from "Shanghai Maclean Biochemical Technology Co., Ltd."; the "15% copper oxychloride aqueous solution" was purchased from Shanxi Kexing Pesticide & Fertilizer Co., Ltd., pesticide registration number PD20111191; the "10% mixed amino acid copper aqueous solution" was purchased from Shandong Heze Beilian Pesticide Manufacturing Co., Ltd., pesticide registration number PD20101391; the "20% guanidine copper sulfate aqueous solution" was purchased from Henan Guofeng Jianyuan Agricultural Technology Co., Ltd., pesticide registration number PD20100185.

[0027] Example 1:

[0028] An N-hydroxymethylglycine copper antibacterial agent, comprising the following steps:

[0029] Step 1: Preparation of N-hydroxymethyl amino acid copper: 12.7 kg of N-hydroxymethylglycine sodium and 10.0 kg of copper acetate monohydrate were added to a reaction vessel, along with 100 kg of distilled water. The mixture was heated at 60°C and stirred continuously for 3 hours. Then, it was cooled to room temperature (25°C) to crystallize. The mixture was filtered, washed with a small amount of water, and dried to obtain 16.3 kg of N-hydroxymethylglycine copper.

[0030] Step 2: Preparation of 30% N-hydroxymethylglycine copper aqueous suspension: By weight, 30% N-hydroxymethylglycine copper, 7% sodium polynaphthalene sulfonate, 0.4% hydroxypropyl methylcellulose, 5% glycerol, and 0.3% polyether-modified silicone defoamer are mixed, with the remainder being water. The above materials are added to an open bottle and subjected to high shear to refine and homogenize them, thus obtaining the 30% N-hydroxymethylglycine copper aqueous suspension.

[0031] Example 2:

[0032] Indoor toxicity test of 30% N-hydroxymethylglycine copper aqueous suspension

[0033] Test pathogens: Gray mold of leeks, white mold of celery, and wilt of strawberries.

[0034] Experimental Method: The mycelial growth rate method was used for determination. The test solution was 30% N-hydroxymethylglycine copper aqueous suspension, and the control solutions were 15% copper oxychloride aqueous solution, 10% mixed amino acid copper aqueous solution, and 20% guanidine·copper sulfate aqueous solution. The test and control solutions were diluted with water to prepare solutions with copper elemental weight contents of 1600 μg / mL, 800 μg / mL, 400 μg / mL, 200 μg / mL, 100 μg / mL, and 50 μg / mL, respectively, for later use. The above solutions were diluted with PDA agar medium cooled to 55℃±1℃ at a ratio of 1:9 to prepare test plate media for later use. Sterile water and PDA agar medium were mixed as described above to prepare blank control media for later use. A 5 mm diameter mycelial cake was taken and inoculated into the test plate media and blank control media respectively, ensuring that the side containing colonies was in full contact with the medium.

[0035] The mycelial diameter was measured using the cross-cross method. The mycelial growth inhibition rate was calculated using the following formula.

[0036]

[0037] In the formula, I is the mycelial growth inhibition rate (%); D is the diameter of the mycelial cake (mm); D1 is the diameter of the colony in the blank group (mm); and D2 is the diameter of the colony in the test group (mm).

[0038] From the appendix Figure 2-4 It is known that the 30% N-hydroxymethylglycine copper aqueous suspension of the present invention has a significantly better antibacterial effect against gray mold of leeks, white mold of celery and wilt of strawberries than 15% copper oxychloride aqueous solution, 10% mixed amino acid copper aqueous solution and 20% guanidine copper sulfate aqueous solution.

[0039] Example 3:

[0040] Field efficacy trial of 30% N-hydroxymethylglycine copper aqueous suspension

[0041] Target diseases for prevention and control: gray mold of leeks, white mold of celery, and wilt of strawberries.

[0042] The test solution was 30% N-hydroxymethylglycine copper aqueous suspension, and the control solutions were 15% copper oxychloride aqueous solution, 10% mixed amino acid copper aqueous solution, and 20% guanidine copper sulfate aqueous solution. Water served as a blank control. The test and control solutions were diluted with water to achieve the same copper concentration. The application method was conventional spraying, with two applications 10 days apart. A survey was conducted 14 days after the last application. The disease index and control effect were calculated using the following formulas.

[0043]

[0044] In the formula, CK is the disease index of the blank control area; PT is the disease index of the drug-treated area.

[0045] The results of the field efficacy trials are shown in Table 1.

[0046] Table 1 Field efficacy trials

[0047]

[0048] Table 1 shows that, regarding the field efficacy of 30% N-hydroxymethylglycine copper aqueous suspension, 15% copper oxychloride aqueous solution, 10% mixed amino acid copper aqueous solution, and 20% guanidine·copper sulfate aqueous solution in controlling gray mold of leeks, white mold of celery, and wilt of strawberries, all four organic copper preparations can effectively control plant diseases. Moreover, the 30% N-hydroxymethylglycine copper aqueous suspension has a significantly better control effect on the three diseases than the 15% copper oxychloride aqueous solution, 10% mixed amino acid copper aqueous solution, and 20% guanidine·copper sulfate aqueous solution.

[0049] The above are merely some specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. All modifications directly or indirectly derived by those skilled in the art from the disclosure of the present invention should be considered within the scope of protection of the present invention.

Claims

1. An N-hydroxymethylglycine copper antibacterial agent, characterized in that: The antibacterial agent is an aqueous suspension prepared from the following components and processes in weight percentage: 30% N-hydroxymethylglycine copper, 7% sodium polynaphthalene sulfonate, 0.4% hydroxypropyl methylcellulose, 5% glycerol, and 0.3% polyether-modified silicone defoamer, mixed together, with the remainder being water; the above components are added to an open bottle and subjected to high shear to refine and homogenize them to obtain the antibacterial agent used to prevent and control celery white mold disease.

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