Solid compositions as soluble precursors for environmentally friendly and effective metal-based biocides, methods and uses thereof

Abstract

The present invention relates to a solid composition comprising a homogeneous mixture of at least one source of inorganic metal (the metal being copper (II) and / or zinc (II)) and a carboxylic acid having at least two carboxyl groups; and the metal / acid molar ratio is 1 to 2. The composition is advantageous as a precursor for the preparation of biocidal solutions having high biocidal activity, easy application, low toxicity or no (plant) toxicity, and very good durability. The invention also relates to a method for producing said precursor, a method for producing a biocidal solution from said precursor, a plant protection method and the use of a biocide.

Description

Technical Field

[0001] The present invention relates to solid compositions which are particularly suitable as precursors for the preparation of highly effective metal-based biocidal solutions. In particular, the present invention relates to metal-based compositions in solid form which are soluble (especially in water) and which, once their solution is applied to plants, plant products, seeds, tubers and / or fruits, form an insoluble or sparingly soluble compound, thereby providing significantly good biocidal activity over a long period of time and reducing the risk of leaching in the soil.

[0002] The invention also relates to a process for preparing a biocidal solution from said solid composition and to its subsequent use on plants, plant products, seeds, tubers and / or fruits.

[0003] The invention also relates to the use of the composition as a biocide, in particular as a fungicide and / or as a bactericide, for example in the fields of agriculture, lawn and garden, forestry and general disinfection. Background Art

[0004] Biocides refer to a broad class of chemicals that includes botanical drug products and antimicrobial agents used for medical, veterinary, household or industrial purposes, as well as disinfectants for fluids and surfaces, such as water, floors, swimming pools, countertops, etc.

[0005] In particular, pesticide / phyto-pharmaceutical products, such as fungicides and bactericides, are important agricultural protective agents. In fact, crops are attacked by many diseases, especially by specific infectious pests belonging to the bacterial and fungal kingdoms. These pests pose a constant threat to many crops, and their control is of great economic importance, because the growth of bacteria or fungi on plants can inhibit the production of leaves, fruits or seeds, and can reduce the overall quality and / or yield of the crops. In addition, some species of fungi can produce mycotoxins in infected crops, which can cause health problems for humans and animals.

[0006] Fungicides are chemical or biological agents known in the art for reducing, inhibiting or destroying fungi. Bactericides are chemical or biological agents known in the art for reducing, inhibiting or destroying bacteria.

[0007] The use of copper, in particular Cu(II) ions, for the protection or treatment of crops against attack by certain phytopathogenic fungi and bacteria has long been known.

[0008] For example, it is well known that copper sulfate is a good fungicide, but it is highly phytotoxic, especially due to its acidic properties. When copper sulfate is combined with an alkaline agent such as calcium hydroxide or sodium hydroxide to form a neutralized form, its phytotoxicity is reduced, but it still exists. For example, one of the neutralized forms has been used for a long time and is still in use today. It is well known and is called the "Bordeaux mixture", which is a suspension of copper sulfate and lime, the proportions of which have changed over time. For example, it was used as early as 1882 to control downy mildew on grapes.

[0009] Other copper (II) based fungicides are also known, such as cupric oxychloride, cupric hydroxide, cupric carbonate and cuprous oxide. Unfortunately, like Bordeaux mixture, they are poorly soluble in water at neutral pH. For example, the solubility of cupric hydroxide in water is very low (about 0.5 mg / L at 20°C).

[0010] The biocidal activity of copper(II)-based fungicides is due to the free Cu that is (bio)available for fungal consumption. 2+ ions, which is measured with free Cu 2+ The release of ions is proportional to the release of ions. Therefore, insoluble conventional copper (II) based fungicides are usually applied in large quantities on plants to effectively inhibit the development of pathogenic fungi. At a pH of 7, the amount of soluble aqueous copper Cu released is proportional to the release of ions. 2+ The amount of available Cu is only a few ppm, and even less is released at higher pH values. 2+ ions, are also sufficient to ensure good antifungal activity.

[0011] However, despite their biocidal effectiveness, conventional copper (II) based fungicides also exhibit a number of disadvantages, as described below.

[0012] First, these copper(II)-based compounds are phytotoxic, particularly when used at high and / or repeated rates and / or on delicate plants / cultivars, causing leaf necrosis or burns.

[0013] Second, to achieve the appropriate available Cu 2+ level, requiring a relatively large amount of copper-based compounds, which greatly affects the cost-effectiveness and, most importantly, causes serious soil residue pollution.

[0014] Third, Cu released from solid / insoluble compounds applied / deposited on plants (e.g. by spraying) 2+ The amount of Cu ions is uncontrollable because it is affected unpredictably by local environmental conditions (such as ambient humidity, dissolved carbon dioxide gas, temperature, etc.). 2+The amount of ions may change, leading to an increased risk of phytotoxicity, for example to more vulnerable cultivars.

[0015] Next, many other disadvantages of conventional copper (II) based fungicides come from their insolubility in water, which forces them to be used usually in the form of suspensions in water. This requirement to use suspensions significantly brings about the following problems:

[0016] - clogging problems of applicators, spraying systems (commonly used in this type of application);

[0017] - problems of suspension instability due to sedimentation of solid components (resulting in the need for appropriate repeated mixing steps and / or in an uncontrolled decrease in the solid / water ratio of the suspension); and

[0018] -Poor coverage / spreading on plants and / or uneven coverage.

[0019] In order to reduce or avoid clogging and / or settling, integrated agitation is sometimes used in the application system, but this results in a more complex and expensive system, and agitation often does not completely solve the problem.

[0020] Finally, Cu 2+ Solid compound particles of the ion reservoir are partially lost by leaching during rain, resulting in reduced or absent biocidal activity. This requires repeated applications of conventional copper (II)-based fungicides on the same crop (typically 6-10 times per year, up to 20 times depending on climate, crop properties and crop management), which negatively affects cost-effectiveness and soil contamination due to leaching.

[0021] In addition, the use of known insoluble copper compounds such as cupric hydroxide, cupric carbonate or cuprous oxide in the presence of ligands / chelators to enhance their solubility and control Cu 2+ bioavailability.

[0022] In particular, it is known from patent application WO 91 / 13552 to combine copper(II) with four ammonia molecules to form a complex, which, due to the solubility of copper and the high levels of Cu available, 2+ , which can improve fungicidal activity. However, the high solubility makes this "copper complex" completely leachable, with low persistence on plants. This therefore requires more timely applications and increased frequency of applications, which eliminates the positive effect of its solubility on its overall biocidal effect (the amount of metal applied overall will increase) and increases the impact on the environment.

[0023] Patent US6562757 describes a plant protection composition comprising a copper source (such as copper (II) hydroxide) and a small amount of a chelating compound (such as calcium citrate or calcium malate, the acidity of which is pre-neutralized with calcium hydroxide). According to US6562757, this can partially dissolve the insoluble copper source (up to 43%), thereby increasing the bioavailable Cu 2+ ions and gradually releases them while controlling the partial leaching. However, the bioavailable Cu 2+ The amount of ions is still low and the precursor composition is still partially insoluble, so that the problems associated with the application of suspensions are not solved.

[0024] There is also a name Dentamet is a commercial product that can be used as a fertilizer and protect some plants. The product is sold in the form of a solution of copper (II) sulfate and zinc (II) sulfate (metal content 2% and 4%, respectively) containing citric acid and a pH of 2.5. Unfortunately, the solubility of copper and zinc sulfate makes this product very easy to leach and has very low persistence on plants, the negative consequences of which have been mentioned above. It should be noted that when the Dentamet solution evaporates, the components of the solution, namely the mixture of copper sulfate, zinc sulfate and citric acid, are in solid form. In addition, fungicides / fertilizers in liquid form are not popular among users because of the shorter shelf life of such products compared to powdered / solid products, as well as the larger shipping volume and heavier weight (resulting in higher shipping costs).

[0025] It should also be noted that, in addition to being most phytotoxic, all copper(II)-based fungicides on the market for plant protection, including Dentamet products, are GHS classified H400 or H410, meaning they are considered hazardous due to being highly toxic (with long-lasting effects) to aquatic organisms.

[0026] However, global health and environmental regulations are becoming increasingly stringent, for example requiring the reduction of chemical residues in crops and soils and the use of less toxic and more environmentally friendly biocidal products. In particular, the maximum permitted application rate for copper (at least in Europe) is 28 kg / ha over 7 years, but the goal in the future is to reduce this maximum application rate as much as possible to minimize copper accumulation in the soil and exposure of non-target organisms to copper.

[0027] Therefore, there remains a need for metal-based biocides (particularly bactericides and / or fungicides) that: (i) have high biocidal activity while requiring less metal per treated surface (e.g. crop surface) over time compared to conventional copper(II)-based fungicides; (ii) are easy to apply, e.g. avoid clogging and sedimentation problems; (iii) have low or no (phyto)toxicity; and (iii) show a good balance between easy leaching and persistence on plants.

[0028] Purpose of the Invention

[0029] The main object of the present invention is to overcome the above-mentioned disadvantages of the prior art.

[0030] More precisely, the object of the present invention is to provide compositions in solid form which are particularly suitable as precursors for the preparation of metal-based biocidal solutions.

[0031] In particular, the object of the present invention is to provide a composition in solid form which is particularly suitable for use as a precursor for the preparation of metal-based biocidal solutions, showing high biocidal activity, in particular requiring less metal per treated surface compared to conventional copper(II)-based fungicides.

[0032] Another object of the present invention is to provide compositions in solid form which are particularly suitable as precursors for preparing metal-based biocidal solutions having acceptable or no phytotoxicity.

[0033] Another object of the present invention is to provide compositions in solid form which are particularly suitable as precursors for preparing metal-based biocidal solutions which exhibit low or no toxicity to fish, birds, mammals and bees.

[0034] Another object of the present invention is to provide a composition in solid form which is particularly suitable as a precursor for the preparation of a metal-based biocidal solution which is easy to apply, for example avoiding clogging and sedimentation problems.

[0035] Another object of the present invention is to provide metal-based compositions in solid form which are particularly suitable for use as precursors for the preparation of biocidal solutions showing a balance between high leaching (high solubility) and high persistence (low solubility) on plants.

[0036] Another object of the present invention is to provide a composition in solid form which is particularly suitable as a precursor for the preparation of a metal-based biocidal solution which is cost-effective, environmentally friendly and simple to prepare and which can be applied to plants, plant products, seeds, tubers and / or fruits.

[0037] Another object of the present invention is to provide a solution to the disadvantages of the prior art which is simple and inexpensive to manufacture and use. Summary of the invention

[0038] The present invention relates to a composition in solid form comprising an intimate mixture of a solid compound (A) and a solid compound (B):

[0039] - Compound (A) is at least one inorganic metal source, the metal being copper (II) or zinc (II);

[0040] - Compound (B) is a carboxylic acid having at least two carboxyl groups;

[0041] wherein the metal / acid molar ratio is 1 to 2, and:

[0042] - when the metal is copper(II), the at least one inorganic metal source is copper(II) hydroxide;

[0043] - When the metal is zinc(II), the at least one inorganic metal source is zinc(II) oxide.

[0044] The present invention therefore relates to a novel and inventive process, since it makes it possible to overcome the disadvantages of the prior art. The inventors have indeed found that the homogeneous combination of a solid inorganic copper(II) and / or zinc(II) source with a specific chelating molecule in a specific stoichiometry (metal / acid molar ratio) gives a solid composition which is very soluble in an aqueous medium and is therefore suitable as a precursor for the preparation of a solution for application to plants. Furthermore, it has surprisingly been found that from said solution an irreversibly insoluble or slightly soluble compound can be obtained (e.g. upon evaporation of the water), which has a high biocidal activity, shows a good balance between leaching and persistence and has no or very low phytotoxicity. Finally, it has also been found that the insoluble or slightly soluble compound obtained shows very low or no toxicity (e.g. to fish, birds, mammals and bees).

[0045] Therefore, in view of the current state of the art in the field of metal-based biocides, the present invention solves the problems raised and exposed above.

[0046] The present invention is surprising and inventive, in particular because it combines the advantages of solubility (before / during application on the plant) and insolubility (after and once applied on the plant). In fact, the present invention provides a precursor in solid form which is soluble in water and forms an advantageous clear solution, but once said solution is applied to the plant, irreversibly forms an advantageous insoluble or slightly soluble compound (without or with low (phyto)toxicity) when the water evaporates.

[0047] The present invention also relates to a process for preparing a composition of the present invention in solid form, comprising the step of mixing solid compound (A) and solid compound (B) by applying a mechanical action to obtain a homogeneous mixture.

[0048] The present invention also relates to a method of preparing a biocidal solution, the method comprising the step of combining a composition of the present invention in solid form with a solvent, the solvent comprising water.

[0049] Furthermore, the present invention also relates to a method for preventing or inhibiting the growth of live pathogenic organisms on plants, plant products, seeds, tubers and / or fruits, the method comprising the following steps in sequence:

[0050] a) preparing a biocidal solution according to the first method of the present invention; and

[0051] b) applying the solution to plants, plant products, seeds, tubers and / or fruits.

[0052] Finally, the present invention also relates to the use of the composition of the present invention in solid form as a biocide in the following aspects:

[0053] i) Agriculture, including field crops, horticulture, arboriculture, viticulture, as pre-harvest and / or post-harvest treatments;

[0054] ii) Lawns and gardens, including specialist turf;

[0055] iii) Forestry;

[0056] iv) General disinfection area.

[0057] Other features and advantages of the present invention will become more apparent from the following description of preferred embodiments.

[0058] In this document, when a range is indicated, the endpoints are included unless expressly stated otherwise. In addition, all integer values ​​and sub-domain values ​​within the numerical range are expressly included as if expressly written.

[0059] The composition of the present invention comprises a homogeneous mixture of a solid compound (A) and a solid compound (B).

[0060] The "homogeneous mixture" of the present invention, according to the common understanding in the chemical community, refers to a mixture of at least two solid particles of different properties / compositions, which is uniform and shows close combination or combination of the solid particles, such as interaction between compound (A) and compound (B) particles and / or coating of compound (A) particles on compound (B) particles.

[0061] According to the invention, a homogeneous mixture can be obtained using various devices or techniques, all of which are known in the art and allow mechanical action, including, for example, advantageously mixing by ball milling and mixing by twin-screw extrusion.

[0062] According to the invention, compound (A) is at least one inorganic metal source, the metal being copper (II) or zinc (II).

[0063] The advantage of copper (II) is that it has long been proven to be highly effective against fungi or bacteria. Zinc (II) is a favorable alternative to copper (II) because zinc (II) also has biocidal activity (even if the biocidal activity of zinc (II) is generally lower than that of copper on some diseases) and zinc (II) has less impact on health and the environment than copper.

[0064] According to the present invention, when the metal is copper (II), the at least one inorganic metal source is copper (II) hydroxide (Cu (OH) 2). According to this embodiment, preferably, the at least one inorganic copper (II) source consists essentially of copper hydroxide (or Cu (OH) 2). More preferably, compound (A) consists essentially of copper hydroxide (which means that no other inorganic sources of copper (II) are present / added in the composition, excluding impurities that may be present in the starting materials).

[0065] According to the present invention, when the metal is zinc (II), the at least one inorganic metal source is zinc (II) oxide (ZnO). According to this embodiment, preferably, the at least one inorganic zinc (II) source consists essentially of zinc oxide (ZnO). More preferably, compound (A) consists essentially of zinc (II) oxide (which means that no other inorganic sources of zinc (II) are present / added in the composition, excluding impurities that may be present in the starting materials).

[0066] According to another embodiment of the present invention, compound (A) comprises copper (II) hydroxide and zinc (II) oxide. More preferably, compound (A) consists essentially of copper (II) hydroxide and zinc (II) oxide (which means that no other inorganic sources of zinc (II) and copper (II) are present / added in the composition, excluding impurities that may be present in the starting materials). The co-presence of a copper (II) source and a zinc (II) source can synergistically improve the biocidal activity, because less metal amount (total amount of copper + zinc) is required to achieve the same biocidal activity / efficacy compared to using either metal alone.

[0067] When compound (A) comprises at least one inorganic zinc (II) source and at least one inorganic copper (II) source, the ratio of Cu:Zn in the composition is preferably about 2:1, or alternatively about 1:2.

[0068] According to the invention, compound (B) is a carboxylic acid having at least two carboxyl groups, optionally with at least one hydroxyl group.

[0069] The following table lists examples of carboxylic acids according to embodiments of the present invention:

[0070]

[0071] Preferably, compound (B) is a carboxylic acid having at least three carboxyl groups, optionally with at least one hydroxyl group.

[0072] In a more preferred embodiment, compound (B) is trans-aconitic acid, tricarballylic acid or citric acid.

[0073] In a most preferred embodiment, compound (B) is citric acid. Citric acid is a carboxylic acid having three carboxyl groups and one hydroxyl group. For example, compound (B) is anhydrous or monohydrated citric acid. The advantages of citric acid in the present invention are that it is cheap, has good chelating ability for copper (II) or zinc (II), and has low (plant) toxicity itself. In addition, most importantly, it has been demonstrated that, in the specific stoichiometry of the present invention (metal / acid molar ratio), citric acid can react with copper (II) and zinc (II) to form (1) an aqueous solution (thereby dissolving an insoluble inorganic copper source or zinc source) and (2) an insoluble or slightly soluble low (plant) toxicity compound / complex after crystallization / precipitation (e.g., by evaporation of water).

[0074] In the composition according to the invention, the metal / acid molar ratio is between 1 and 2. For the sake of clarity, this molar ratio is obtained by dividing the number of moles of metal of the inorganic metal source by the number of moles of carboxylic acid molecules. This molar ratio range, combined with the other characteristics of the composition, makes it possible to achieve the objects of the invention, in particular to obtain a solid composition capable of forming a solution in water and irreversibly forming an insoluble or slightly soluble compound upon evaporation of water and / or precipitation / crystallization.

[0075] In an advantageous embodiment, the metal / acid molar ratio is equal to or lower than 1.9; 1.8; 1.7; 1.6 or 1.5.

[0076] In another advantageous embodiment, the metal / acid molar ratio is equal to or higher than 1.05; 1.1; 1.2; 1.3 or 1.4.

[0077] In the present invention, the upper and lower limits of this molar ratio make it closer to the determined optimal stoichiometry, that is, the stoichiometry of metal: acid is 3: 2 and / or 2: 1. A slight deviation from the stoichiometry of 3: 2 or 2: 1 does not hinder the purpose of the present invention, but it is better to be closer to 1.5 or 1.67 (the target is a stoichiometry between 3: 2 and 2: 1) or closer to 2.

[0078] Also preferably, the metal / acid molar ratio is from 1.1 to 2, or even from 1.2 to 2, or from 1.3 to 2, or even from 1.4 to 2.

[0079] According to a very preferred embodiment, the metal / acid molar ratio is about 1.5.

[0080] According to another very preferred embodiment, the metal / acid molar ratio is about 2.

[0081] According to another very preferred embodiment, the metal / acid molar ratio is about 1.67.

[0082] According to one embodiment, the composition of the present invention is soluble in water (i.e., the solubility is greater than 1 g / L at 20° C.). In particular, the composition of the present invention has a water solubility of at least 30 g / L, at least 40 g / L, at least 50 g / L, or preferably at least 60 g / L, or even at least 70 g / L or better yet, at least 80 g / L at 20° C.

[0083] According to one embodiment, the composition of the present invention is in the form of a powder, granules or tablets. If in powder form, it is preferably in the form of a free-flowing powder.

[0084] In addition to compound (A) and compound (B), the composition of the present invention may also include other ingredients / additives without departing from the present invention. For example, the composition of the present invention may include at least one additive selected from pH regulators, film formers, anti-caking agents, surfactants, wetting agents, defoamers, anti-drift agents, adhesives, thickeners, foaming agents, curing agents, other biocides, fertilizers and stabilizers.

[0085] According to the invention, the method for preparing a biocidal solution comprises the step of combining a composition in solid form with a solvent, the solvent comprising water. Preferably, the solvent is substantially water. This is advantageous because the biocide solution is obtained by simply dissolving the solid composition, in particular in water. Using the composition of the invention as a precursor for a biocidal solution, the problems associated with the use of suspensions and the problems exposed above (clogging, settling or the need for regular mixing, poor plant coverage, etc.) can be avoided.

[0086] Additives may also be used, either pre-added to the solvent, added after the solution is prepared, or combined with the solid composition and solvent. Examples of additives include pH adjusters, film formers, anti-caking agents, surfactants, wetting agents, defoamers, anti-drift agents, adhesives, thickeners, foaming agents, curing agents, other biocides, fertilizers, and stabilizers.

[0087] Preferably, the amount of solid composition and solvent is such that the concentration of metal M of the obtained solution is between 0.01 g / L and 5 g / L, preferably between 0.05 g / L and 3 g / L. More preferably, the amount of solid composition and solvent is such that the concentration of metal M of the obtained solution is between 0.1 g / L and 2 g / L.

[0088] According to the present invention, a method for preventing or inhibiting the growth of live pathogenic organisms on plants, plant products, seeds, tubers and / or fruits comprises the following steps in sequence:

[0089] a) combining the composition of the present invention with a solvent to prepare a biocidal solution, the solvent comprising water (a method of preparing a biocidal solution of the present invention); and

[0090] b) applying the solution to plants, plant products, seeds, tubers and / or fruits.

[0091] Figure 1 is a flow chart showing steps (a) and (b) of a method according to the present invention for preventing or inhibiting the growth of live pathogenic organisms on plants, plant products, seeds, tubers and / or fruits.

[0092] According to one embodiment, the step of applying is performed by spraying, crushing, dipping, soaking or coating.

[0093] According to another embodiment, the amount of metal applied to the plants, plant products, seeds, tubers and / or fruits is less than 4000 g / ha (registered maximum dose), preferably less than 3000 g / ha, more preferably less than 2000 g / ha, or even less than 1000 g / ha or less than 500 g / ha. For clarity, the amount of metal according to this embodiment is determined / calculated based on the molar mass of the metallic elements copper and / or zinc.

[0094] According to another embodiment, the method for preventing or inhibiting the growth of live pathogenic organisms on plants, plant products, seeds, tubers and / or fruits comprises, after the step b) of applying, a step c) of crystallizing and / or precipitating a solid compound (C) that is slightly soluble in water to insoluble in water on the plants, plant products, seeds, tubers and / or fruits. For example, the step c) of crystallization and / or precipitation is carried out by solvent evaporation, such as natural water evaporation (by ambient temperature, wind, etc.). By the step c) of the present invention, a solid compound (C) is formed on the plants, plant products, seeds, tubers and / or fruits in the form of an amorphous precipitate or a crystalline form or a mixture thereof.

[0095] In particular, when compound (B) is citric acid, solid compound (C) comprises a complex with citric acid, and the ionization state of citric acid ranges from 0 (C6H8O7) to -4 (C6H4O7). 4- .

[0096] In one embodiment, when compound (B) is citric acid, the solid compound (C) of the present invention comprises at least one compound having the formula Cu w Zn x (C6H y O7)z Citrate and / or hydrate thereof, wherein

[0097] -0≤w≤3;

[0098] -0≤x≤3;

[0099] -1≤(w+x)≤3;

[0100] -4≤y≤8;

[0101] -1≤z≤2;

[0102] -1≤(w+x) / z≤2 (for the sake of clarity, (w+x) / z corresponds to the metal / acid molar ratio according to the present invention).

[0103] In a preferred embodiment, when compound (B) is citric acid, the solid compound (C) comprises (i): copper citrate having the formula Cu3(C6H5O7)2 or Cu2(C6H4O7), or (ii): zinc citrate having the formula Zn3(C6H5O7)2, or (iii): mixed zinc citrate copper having the formula ZnCu2(C6H5O7)2, or (iv): mixed zinc citrate copper having the formula Zn2Cu(C6H5O7)2, or (v): hydrates of (i) or (ii) or (iii) or (iv), or mixtures thereof.

[0104] Without departing from the scope of the present invention, in addition to the copper and / or zinc citrate, the solid compound (C) may also contain other soluble or insoluble compounds. For example, the solid compound (C) may include "free" citric acid (e.g., if the citric acid is in excess in the solid form composition of the present invention compared to the target stoichiometry of the insoluble metal citrate).

[0105] Preferably, when compound (B) is citric acid, the solid compound (C) consists essentially of: (i) copper citrate having the formula Cu3(C6H5O7)2 or Cu2(C6H4O7), or (ii) zinc citrate having the formula Zn3(C6H5O7)2, or (iii) mixed zinc-copper citrate having the formula ZnCu2(C6H5O7)2, or (iv) mixed zinc-copper citrate having the formula Zn2Cu(C6H5O7)2, or (v) a hydrate of: (i) or (ii) or (iii) or (iv), or a mixture thereof.

[0106] In particular, copper citrates, particularly those of the formula Cu3(C6H5O7)2 and its hydrates or those of the formula Cu2C6H4O7 and its hydrates (e.g., Cu2(C6H4O7).H2O) are advantageous because their low solubility increases their persistence while still having high biocidal activity and they are non-toxic to fish, birds, mammals and bees (see in particular "Pesticide Toxicity Profile: Copper-based Pesticides" from Fishel (2011), Pesticide Information Office, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida).

[0107] In addition, zinc citrate, especially Zn3(C6H5O7)2 and its hydrates, are also very advantageous because their low solubility increases their persistence while maintaining good biocidal activity and are "generally recognized as safe" food ingredients. In fact, in Europe, zinc citrate has been included in the positive list of Regulation (EC) No. 1925 / 2006 on food fortification. Directive 2002 / 46 / EC of the European Parliament and of the Council on food supplements also lists zinc citrate as a vitamin and mineral that can be used to make food supplements. In addition, it is listed as a mineral salt in EU Regulation (EC) No. 609 / 2013 on infant foods, foods for special medical purposes and total dietary alternatives for weight control. Secondly, in the United States, zinc citrate can be regarded as a substance classified as a dietary ingredient under the provisions of §201(ff) of the FDC Act. In oral care, zinc citrate products are classified as Class I active ingredients in terms of safety and as Class III active ingredients in terms of efficacy. Since 2009, zinc citrate has been recognized as “generally recognized as safe” (self-certified GRAS), fully compliant with the provisions of the US Food, Drug, and Cosmetic Act.

[0108] Advantageously, the solubility of compound (C) is lower than or equal to 1 g / L. Preferably, it is lower than or equal to 0.8 g / L. Also preferably, it is higher than or equal to 0.1 g / L or better, higher than or equal to 0.2 g / L, or even 0.3 g / L. More preferably, the solubility of compound (C) is higher than or equal to 0.5 g / L.

[0109] This is beneficial in achieving a balance between good Cu(II) bioavailability and high leaching / persistence, especially compared to the very low solubility of copper hydroxide.

[0110] According to the present invention, the composition in solid form can be used as a biocide, in particular a fungicide and / or a bactericide, in the following fields:

[0111] i) Agriculture, including field crops, horticulture, arboriculture, viticulture, as pre-harvest and / or post-harvest treatments;

[0112] ii) Lawns and gardens, including specialist turf;

[0113] iii) forestry; and

[0114] iv) General disinfection area.

[0115] In the general field of disinfection, compositions in solid form can be advantageously used for a variety of applications, such as, but not limited to, medical, veterinary, household and industrial uses, such as use as disinfectants for fluids (water, air, etc.) and surfaces (floors, work surfaces, toilets, medical devices, prostheses, etc.).

[0116] In particular, the compositions in solid form according to the invention are used as biocides in the following fields:

[0117] i) Agriculture, including field crops, horticulture, arboriculture; viticulture, as pre-harvest and / or post-harvest treatments;

[0118] ii) Lawns and gardens, including specialist turf; and

[0119] iii) Forestry.

[0120] The compositions of the present invention can be advantageously used as biocides for treating various bacterial and fungal diseases on various plants, plant products, seeds, tubers and / or fruits. In particular, the compositions of the present invention can be advantageously used as fungicides, for example for treating fungal diseases on grapevines and many other crops, such as, but not limited to, grapevine downy mildew (Plasmopara viticola), potato mildew (Phytophtora infestans) and grey mould (Botrytis cinerea).

[0121] Preferably, in the use of the present invention, the composition in solid form of the present invention is used in the form of an aqueous solution, optionally together with at least one additive selected from pH regulators, film formers, anti-caking agents, surfactants, wetting agents, defoamers, anti-drift agents, thickeners, foaming agents, curing agents, other biocides, fertilizers and stabilizers.

[0122] The composition of the present invention is also beneficial for promoting plant growth and can therefore be used as a fertilizer (e.g., foliar fertilizer). In fact, zinc and copper are essential elements for plant growth. For example, zinc is very important for root development and crop emergence due to its role in growth hormone synthesis, and copper can increase photosynthesis and enzyme activity and also plays an important role in the formation of cell wall lignin.

[0123] The embodiments of the present invention will now be further described by way of examples and comparative examples not in accordance with the present invention. The following examples are for illustrative purposes only and are not intended to limit the scope of the present invention. Example

[0124] 1) Preparation of the solid form composition of the present invention

[0125] The preparation of the composition of the present invention was carried out in a continuous process using a Thermo Electron EuroLabXL16 40 L / D high torque twin screw extruder equipped with three Brabender DDW-MD2-DDSR20N gravimetric starting material metering devices.

[0126] The TSE (Twin Screw Extruder) is equipped with two intermeshing co-rotating screws (200-400rpm) mounted on splined shafts in a temperature-controlled closed barrel. The screws are designed to be tight and self-wiping, eliminating stagnant zones along the entire length of the process section. This allows for a homogenous mix and a free-flowing powder.

[0127] Each solid composition (1-5) was analyzed by powder X-ray diffraction, using Bragg Brentano geometry, Kalpha 1 radiation provided by a Johannson monochromator, and measuring for 1 hour per sample.

[0128] - Composition 1:

[0129] Anhydrous citric acid and copper (II) hydroxide were mixed at a rate of 10 Kg / h in the following manner, with a molar ratio of copper:acid of 3:2:

[0130] Starting Materials CAS Brabender 1(Kg / h) Brabender 2(Kg / h) Copper hydroxide 20427-59-2 4.324 - Anhydrous citric acid 77-92-9 - 5.676

[0131] XRD analysis of the obtained solid composition showed a binary mixture of two components (anhydrous citric acid and copper hydroxide) (their respective XRD patterns were superimposed).

[0132] Composition 1 contained 28.16 wt % copper (Cu).

[0133] - Composition 2:

[0134] Anhydrous citric acid and zinc (II) oxide were mixed at a rate of 10 Kg / h in the following manner, with a zinc:acid molar ratio of 3:2:

[0135] Starting Materials CAS Brabender 1(Kg / h) Brabender 2(Kg / h) Zinc Oxide 1314-13-2 3.885 - Anhydrous citric acid 77-92-9 - 6.115

[0136] XRD analysis of the obtained solid composition showed a binary mixture of two components (anhydrous citric acid and zinc oxide) (their respective XRD patterns were superimposed).

[0137] Composition 2 contained 31.23 wt% of metallic zinc (Zn).

[0138] - Composition 3:

[0139] Anhydrous citric acid, copper (II) hydroxide and zinc (II) oxide were mixed at a rate of 10 Kg / h in the following manner, with a molar ratio of copper:zinc:acid of 2:1:2:

[0140]

[0141]

[0142] XRD analysis of the obtained solid composition showed a ternary mixture of three components (anhydrous citric acid, copper hydroxide and zinc oxide) (their respective XRD patterns were superimposed).

[0143] Composition 3 contained 19.23 wt % of metallic copper (Cu) and 9.90 wt % of metallic zinc (Zn).

[0144] - Composition 4:

[0145] Anhydrous citric acid (2 moles), copper hydroxide (1 mole) and zinc oxide (2 moles) were mixed at a rate of 10 Kg / h in the following manner, with a molar ratio of copper:zinc:acid of 1:2:2:

[0146]

[0147] XRD analysis of the obtained solid composition showed a ternary mixture of three components (anhydrous citric acid, copper hydroxide and zinc oxide). Figure 2 It can be clearly seen that it shows the XRD patterns of (b) solid composition 4, (c) copper hydroxide, (d) zinc oxide and (e) anhydrous citric acid. Pattern (b) is the superposition of each XRD pattern (c), (d) and (e).

[0148] Composition 4 contained 9.86 wt % of metallic copper (Cu) and 20.30 wt % of metallic zinc (Zn).

[0149] - Composition 5:

[0150] Anhydrous citric acid (1 mole) and copper hydroxide (2 moles) were mixed at a rate of 10 Kg / h in the following manner, with a copper:acid molar ratio of 2:1:

[0151]

[0152] XRD analysis showed a binary mixture of two components (anhydrous citric acid and copper hydroxide) (overlay of their individual XRD patterns).

[0153] Composition 5 contained 32.82 wt % of metallic copper (Cu).

[0154] 2) Preparation of biocidal solution

[0155] -Solution from composition 1:

[0156] Different amounts of solid composition 1 were added to water at room temperature while gently stirring at 500 RPM using a Velp Scientifica magnetic diverter with a PTFE ordinary stirring bar (solution 1a: 0.67 g / L; solution 1b: 1.34 g / L; solution 1c: 2.68 g / L; solution 1d: 4.03 g / L). A clear solution was obtained after 1-5 minutes.

[0157] -Solution from composition 2:

[0158] Different amounts of solid composition 2 were added to water at room temperature while gently stirring at 500 RPM using a Velp Scientifica magnetic steering device with a PTFE ordinary stirring bar (solution 1a: 0.61 g / L; solution 1b: 1.21 g / L; solution 1c: 2.42 g / L; solution 1d: 3.63 g / L). A clear solution was obtained after 1-5 minutes.

[0159] -Solution from composition 3:

[0160] At room temperature, different amounts of solid composition 3 were added to water while gently stirring at 500 RPM using a Velp Scientifica magnetic diverter with a PTFE regular stirring bar (0.025 g / L to 3 g / L). A clear solution was obtained after 1-5 minutes.

[0161] -Solution from composition 4:

[0162] Different amounts of solid composition 4 were added to water at room temperature while gently stirring at 500 RPM using a Velp Scientifica magnetic diverter with a PTFE ordinary stirring bar (0.025 g / L to 3 g / L). A clear solution was obtained after 1-5 minutes.

[0163] - from the solution in composition 5:

[0164] Different amounts of solid composition 5 were added to water at room temperature while gently stirring at 500 RPM using a Velp Scientifica magnetic diverter with a PTFE regular stirring bar (0.025 g / L to 3 g / L). A clear solution was obtained after 1-5 minutes.

[0165] 3) The result of crystallization

[0166] Compositions 1-5 were dissolved in water at a concentration of 60 g / L. The clear solution obtained was then placed in a glass petri dish and left at room temperature and atmospheric pressure for 24 hours. The solid compound obtained (compound (C) according to the present invention) was filtered and dried, and finally analyzed by powder X-ray diffraction. The Bragg Brentano geometry principle was used for measurement, using Kalpha 1 radiation provided by a Johannson monochromator, and each sample was measured for 1 hour.

[0167] Crystalline compound (C) obtained from composition 1-3: XRD analysis of each compound obtained from crystallization of aqueous solution of composition 1-3 showed that its spectrum did not correspond to the spectrum of (A) and compound (B) present in the starting solid composition 1-3 (i.e., anhydrous citric acid and copper hydroxide and / or zinc oxide).

[0168] Crystalline compound (C) obtained from composition 4: Figure 2 (a) shows the XRD pattern of the solid compound (C) obtained by crystallization of the aqueous solution of composition 4, which does not correspond to the XRD patterns of (A) and compound (B) (i.e., anhydrous citric acid, copper hydroxide and zinc oxide) present in the starting solid composition 4. Figure 2 Also shown are the spectra of (b) solid composition 4 before dissolution, (c) copper hydroxide, (d) zinc oxide, and (e) anhydrous citric acid for comparison. The solid compound (C) obtained after dissolving composition 4 and crystallizing the solution is expected to be a mixed zinc citrate complex of the general formula Zn2Cu(C6H5O7)2.xH2O.

[0169] Crystalline compound (C) obtained from composition 5: Figure 3 (b) shows the XRD pattern of the solid compound (C) obtained by crystallization of the aqueous solution of composition 5. A structural search was performed in ICSD, and the result showed that the hit (CIF ICSD 251344) corresponds to Cu2(C6H4O7).H2O. The theoretical XRD pattern of Cu2(C6H4O7).H2O (CIF ICSD 251344) is shown in Figure 3(a) This result proves that a nearly pure phase of copper citrate compound is obtained by dissolving composition 5 in water and crystallizing it.

[0170] 4) Solubility results

[0171] Solid compositions 1-5: These compositions are completely soluble in water at room temperature with solubility values ​​greater than 80 g / L. Under normal stirring conditions, each composition can form a transparent / clear solution within a few minutes at most.

[0172] In comparison, the solubility of Cu(OH)2 is 0.003 g / L and the solubility of ZnO is 0.004 g / L.

[0173] Compound (C): Each solid precipitate obtained in the solution of composition 1-5 under 3) was suspended in water at a concentration of 10 g / L at room temperature and mixed for 5 minutes (Velp Scientifica magnetic diverter, speed 500 RPM, equipped with PTFE ordinary stirring bar). After centrifugation (Hettich Roto Silenta 630RS, setting speed 3000 RPM-2224RCF), the supernatant was analyzed by enzyme certification dosage procedures for copper and citrate (Agroscope STS022313.5.07.ME.023 and 13.5.07.ME.074) to determine solubility.

[0174] The solid compounds (C) obtained from the solutions of compositions 1-5 all showed solubilities between 0.5 g / L and 1 g / L, which means that they are slightly soluble and therefore show a good compromise between weak to moderate leaching and extended persistence.

[0175] 5) Homogeneous mixture vs simple mixture

[0176] The solubility of the compositions of the present invention (ie, homogenous mixtures) was compared to the solubility of standard high speed simple mixtures of the same proportions of citric acid, copper hydroxide and / or zinc oxide.

[0177] The metals (zinc and / or copper) in the solution (dissolved) were quantitatively analyzed using a high-sensitivity atomic emission spectrometer (Agilent ICP MP-AES 4210).

[0178] A relatively simple high speed mixture was prepared using a high speed Alfa Laval Vortex Shear-Mixer, a standard apparatus for mixing powders.

[0179] After adding 10 g of each composition (the composition of the present invention and the comparative composition) in distilled water at room temperature, the metal concentration in the solution was measured by ICP (the beaker was equipped with a magnetic stirring finger at a rotation speed of 500 rpm).

[0180] - For a mixture of anhydrous citric acid (61.15 wt%) and zinc oxide (38.852 wt%):

[0181]

[0182] - For a mixture of anhydrous citric acid (59.61 wt%), copper hydroxide (15.14 wt%) and zinc oxide (25.25 wt%):

[0183]

[0184] -in conclusion:

[0185] Under our test conditions, it was observed that the dissolution of the composition according to the invention (homogeneous mixture) was practically complete (almost all the metal amount was in solution), whereas the corresponding simple mixtures showed only a moderate solubility of the metal, which means that a large part of the metal source (zinc oxide and / or copper hydroxide) remained insoluble, with the disadvantages explained in the context of the present invention.

[0186] 6) Fungicidal activity results (laboratory test)

[0187] Bioassay of the efficacy of composition 1 against P. viticola on grape leaf disks

[0188] method:

[0189] Compared with the reference product Kocide Opti TM A comparative test was carried out with a suspension concentrate of (based on copper hydroxide, insoluble) composition 1 for the protection against grape downy mildew. Both were standardized to 300 g of metallic copper per hectare at the lowest test rate. The test concentration range (in aqueous solution) was as follows: 1, 2, 4 and 6 times the registered dose of Kocide Opti (solutions 1a, b, c, d). Solutions 1a-d from composition 1 and the suspension of Kocide Opti were applied using a Potter spray tower in a petri dish containing 10 leaf discs (cv Cabernet Sauvignon) placed on filter paper soaked in water. After application, the leaf discs were gently dried under a laminar flow hood. 24 hours after treatment / application, the spore suspension (1×10 5 Spore.ml -1) for inoculation. The inoculation box was sealed and placed in an incubator (constant temperature 22°C, water-soaked filter paper to ensure high humidity, natural light cycle). Seven days after inoculation, the severity of the disease was assessed by estimating the percentage of the leaf disk surface showing spores.

[0190] result:

[0191] The infection rate was satisfactory (78% in the untreated control group).

[0192] Figure 4 The severity (%) of downy mildew on leaf discs is shown for Kocide Opti suspension at the registered dosage concentration (0.19 g / L) and different copper metal concentrations (0.19 g / L, 0.38 g / L, 0.76 g / L and 1.13 g / L) of Inventive Solution 1.

[0193] Severity data were subjected to analysis of variance associated with comparative mean tests (Tukey test: R2 = 0.968; Pr>F: <0.0001, critical value P = 0.05). Data were arcsine transformed before analysis. The same letter indicates no significant difference between different modes (treatments / concentrations).

[0194] These results indicate that Composition 1 of the present invention has similar biocidal activity to Kocide Opti at the registered dosage of copper metal (0.19 g / L).

[0195] Furthermore, at the higher concentration of Composition 1 (Solution 1d), very mild phytotoxicity symptoms were observed, manifested as small necrotic spots.

[0196] This shows that composition 1 according to the invention, besides being easy to apply due to its solubility, is also a suitable precursor for preparing biocidal solutions, having very good biocidal activity (comparable to copper hydroxide) and very low phytotoxicity.

[0197] In addition to these bioassay results, Composition 1 based on copper and citric acid is expected to form a sparingly soluble compound of formula Cu3(C6H5O7)2.xH2O that shows no toxic effects on fish, birds, mammals and bees.

[0198] Bioassay of the efficacy of composition 2 against P. viticola on grape leaf disks

[0199] method:

[0200] Compared with the reference product Kocide Opti TMA comparative test was carried out with a suspension concentrate (based on copper hydroxide, insoluble) to test the preventive protection of composition 2 against grape downy mildew. Both were standardized to 300 g of metallic copper per hectare at the lowest test rate. The test concentration range (in aqueous solution) was as follows: 1, 2, 4 and 6 times the registered dose of Kocide Opti (solutions 2a, b, c, d). Solutions 2a-d from composition 2 and the suspension of Kocide Opti were applied using a Potter spray tower in a petri dish containing 10 leaf disks (cv Cabernet Sauvignon) placed on filter paper soaked in water. After application, the leaf disks were gently dried under a laminar flow hood. 24 hours after treatment / application, the spore suspension (1×10 5 Spore.ml -1 ) for inoculation. The inoculation box was sealed and placed in an incubator (constant temperature 22°C, water-soaked filter paper to ensure high humidity, natural light cycle). Seven days after inoculation, the severity of the disease was assessed by estimating the percentage of the leaf disk surface showing spores.

[0201] result:

[0202] The infection rate was satisfactory (78% in the untreated control group).

[0203] Figure 5 The severity (%) of downy mildew on leaf discs is shown for Kocide Opti suspension using the registered dosage concentration (0.19 g / L) and composition 2 according to the invention at different concentrations of zinc metal solution (0.19 g / L, 0.38 g / L, 0.76 g / L and 1.13 g / L).

[0204] Severity data were subjected to analysis of variance associated with comparative mean tests (Tukey test: R2 = 0.881; Pr>F: <0.0001, critical value P = 0.05). Data were arcsine transformed before analysis. Different letters in the figure indicate significant statistical differences between treatments / concentrations.

[0205] These results show that Composition 2 of the present invention has satisfactory biocidal activity, similar to Kocide Opti at higher concentrations. Although the activity at the lowest concentration was lower than the copper reference concentration, it was still 81% effective.

[0206] Furthermore, at a higher concentration of Composition 2 (Solution 2d), no phytotoxicity symptoms were observed.

[0207] This shows that composition 2 according to the invention, besides being easy to apply due to its solubility, is a suitable precursor for preparing a biocidal solution, has a very good biocidal activity (even lower than that of copper hydroxide) and is non-phytotoxic.

[0208] Finally, it is also expected that composition 2 based on zinc and citric acid will form a sparingly soluble compound of the formula Zn3(C6H5O7)2.xH2O which is non-toxic and "generally recognized as safe".

[0209] Bioassay (in vitro test) of the efficacy of composition 1 and composition 2 against Botrytis cinerea

[0210] method:

[0211] Composition 1 and composition 2 were tested in vitro for their protective effect against gray mold (Botrytis cinerea).

[0212] The determination of the minimum inhibitory concentration (MIC) was based on an in vitro toxicity test in a 24-well plate. Composition 1 and composition 2 were first dissolved in a liquid culture medium (PDB, potato dextrose broth, Difco) at the desired concentration range and then dispensed into a 24-well plate with three replicates for each. The positive control consisted of pure culture medium, while the negative control consisted of a culture medium to which a registered dose of the fungicide Switch (cyprodinil + fludioxonil, Syngenta, Swizerland) was added. Nutrient agar medium (PDA, potato dextrose agar, Difco) maintained at 45°C at a final concentration of 30% v / v was added to solidify the nutrient medium. The inoculum consisted of a conidia suspension from a 10-day-old colony suspended in sterile water (10 5 Up to 10 6 / mL) - 50μL was inoculated into each well. The plates were incubated at 22℃ under natural light cycle. Fungal growth was evaluated 7 days, 14 days and 25 days after inoculation to distinguish between antibacterial and fungicidal effects.

[0213] result:

[0214] As expected, hyphal growth was recorded in the positive control group, whereas hyphal growth was inhibited in the negative control group.

[0215] For composition 1, the MIC value at 7 days post inoculation (dpi) was above 5 g / L, but at 25 dpi, the MIC value increased to between 10 g / L and 20 g / L, indicating that the pathogen could withstand this concentration but was blocked at 20 g / L.

[0216] Composition 2 has a better effect on controlling Botrytis cinerea, and its MIC value is lower, in the range of 5-10 g / L.

[0217] Bioassay of the efficacy of Composition 3 and Composition 4 against P. viticola on grape leaf disks

[0218] method:

[0219] Compared with the reference product Kocide Opti TM (Based on copper hydroxide, insoluble) Suspension Concentrate A comparative test was conducted to test the preventive and protective effects of Composition 3 and Composition 4 on grape downy mildew.

[0220] Based on the downy mildew severity assessment results, the inhibitory concentration (IC) for 50% pathogen infection was calculated using XLSTAT software (four- and five-parameter logistic regression module). 50 For this purpose, a concentration range of 0.025-3 g composition / L (aqueous solution) was tested.

[0221] The solutions from composition 3, composition 4 and the Kocide Opti suspension were applied using a Potter spray tower to a Petri dish containing 10 leaf discs (cv Cabernet Sauvignon) placed on filter paper soaked in water. After application, the leaf discs were gently dried under a laminar flow hood. 24 hours after treatment / application, the spore suspension (1×10 5 Spore.ml -1 ) for inoculation. The inoculation box was sealed and placed in an incubator (constant temperature 22°C, water-soaked filter paper to ensure high humidity, natural light cycle). Seven days after inoculation, the severity of the disease was assessed by estimating the percentage of the leaf disk surface showing spores.

[0222] result:

[0223] The infection rate was satisfactory (77% in the untreated control group) and no spores appeared in the reference group.

[0224] When the concentrations in water were 0.025 g / L and 0.070 g / L, respectively, composition 4 showed IC 50 Better than composition 3. By extrapolation, the IC of composition 3 can be determined 99 (theoretical dosage to completely control the disease) is 0.532 g / L, and the IC of composition 4 99 It is 0.106g / L.

[0225] Furthermore, at the highest tested concentrations of Composition 3 and Composition 4, no phytotoxicity symptoms were observed.

[0226] Comparative results of bioassays of compositions 1-4

[0227] The following table summarizes the results of bioassays against grape downy mildew (P. viticola) using compositions 1-4 of the present invention and commercial Kocide based on their registered dosages. The value of .

[0228] The table lists the metal (Cu and / or Zn) mass percentage and its determined IC for each composition 1-4 and Kocide Opti product. 99 Value (g / L). The IC 99 Values ​​and the amount of metal (g / ha) required to apply 400 L / ha of aqueous solution (standard value).

[0229]

[0230]

[0231] *Registered dosage

[0232] These results show that:

[0233] - Composition 1 was significantly more effective than Kocide Opti (more than 3 times reduction in seasonal copper);

[0234] - Even though composition 2 (Zn only) is not as effective as composition 1 (Cu only), it is still close to Kocide Opti (and has other advantages over Kocide Opti);

[0235] - The combination of Cu and Zn in a solid composition can reduce the amount of metal required / applied compared to a solid composition containing only Cu (or only Zn);

[0236] - The combination of Cu and Zn in a solid composition can significantly reduce the amount of metal required / applied compared to Kocide Opti (up to 20 times more for composition 4).

[0237] Bactericidal activity results (laboratory test)

[0238] method:

[0239] Compositions 1-4 were tested in aqueous solution against several bacteria: Escherichia coli, Staphylococcus aureus, Pseudomonas Aerginosa and Enterococcus hirae.

[0240] Their minimum inhibitory concentration (MIC), the lowest product test concentration sufficient to completely inhibit microbial growth, was determined.

[0241] The test is carried out in accordance with ISO20776-1:2007 standard:

[0242] - Culture medium: Mueller Hinton broth (MHB)

[0243] -Inoculum: 5×10 5 CFU / mL to 8×10 5 CFU / mL (colony forming units per mL of suspension)

[0244] - Temperature 37°C

[0245] -Cultivation time: 18±2 hours

[0246] - Antibiotic verification: Tetracycline

[0247] result:

[0248] The following table lists the results obtained.

[0249]

[0250]

[0251] The MIC values ​​obtained showed moderate to good efficacy against the human pathogens tested.

Claims

1. A composition in solid form comprising a homogeneous mixture of a solid compound (A) and a solid compound (B), - Compound (A) is at least one inorganic metal source, the metal being copper (II) or zinc (II); - Compound (B) is a carboxylic acid having at least two carboxyl groups; It is characterized in that The metal / acid molar ratio is 1 to 2, and: - when the metal is copper(II), the at least one inorganic metal source is copper(II) hydroxide; - When the metal is zinc(II), the at least one inorganic metal source is zinc(II) oxide.

2. The composition according to claim 2, characterized in that The metal / acid molar ratio is about 1.5 or about 1.67 or about 2.

3. The composition according to the preceding claim, characterized in that Compound (B) is a carboxylic acid having at least three carboxyl groups.

4. The composition according to the preceding claim, characterized in that Compound (B) is trans-aconitic acid, tricarballylic acid or citric acid.

5. Composition according to the preceding claim, characterized in that Compound (B) is citric acid.

6. The composition according to any one of the preceding claims, characterized in that Compound (A) comprises copper (II) hydroxide and zinc (II) oxide.

7. The composition according to any one of the preceding claims, characterized in that The composition has a water solubility of at least 60 g / L at 20°C.

8. The composition according to any one of the preceding claims, characterized in that The composition is in the form of powder, granules or tablets.

9. The composition according to any one of the preceding claims, characterized in that The composition comprises at least one additive selected from the group consisting of pH adjusters, film formers, anti-caking agents, surfactants, wetting agents, defoamers, anti-drift agents, adhesives, thickeners, foaming agents, curing agents, other biocides, fertilizers and stabilizers.

10. A method for preparing a composition according to claims 1 to 9, characterized in that The method comprises the step of mixing the solid compound (A) and the solid compound (B) by applying a mechanical action to obtain a homogeneous mixture.

11. The method according to claim 10, characterized in that The mixing was performed by ball milling and twin-screw extrusion.

12. A method of preparing a biocidal solution comprising the step of combining the solid form composition of claims 1-19 with a solvent comprising water.

13. The method according to claim 12, characterized in that The solvent is essentially water.

14. The method according to claims 12-13, characterized in that The amounts of the composition and the solvent are such that the concentration of the metal M in the solution is between 0.01 g / L and 5 g / L, preferably, between 0.1 g / L and 2 g / L.

15. A method for preventing or inhibiting the growth of live pathogenic organisms on plants, plant products, seeds, tubers and / or fruits, characterized in that: The method comprises the following steps in sequence: a) preparing the biocidal solution according to claims 12-15; and b) applying the solution to plants, plant products, seeds, tubers and / or fruits.

16. The method according to claim 15, characterized in that The step of applying is performed by spraying, pulverizing, dipping, soaking or coating.

17. The method according to claims 15-16, characterized in that The method comprises, after step b) of applying, step c) of crystallizing and / or precipitating a solid compound (C) which is sparingly soluble to insoluble in water on the plant, plant product, seed, tuber and / or fruit.

18. The method according to claim 17, characterized in that When compound (B) is citric acid, the solid compound (C) comprises at least one compound having the formula Cu w Zn x (C6H y O7) z Citrate and / or hydrate thereof, wherein 0≤w≤3； 0≤x≤3； 1≤(w+x)≤3; 4≤y≤8； 1≤z≤2； 1≤(w+x) / z≤2 (for the sake of clarity, (w+x) / z corresponds to the metal / acid molar ratio according to the present invention).

19. Use of the composition of claims 1 to 9 as a biocide for: i) Agriculture, including field crops, horticulture, arboriculture, viticulture, as pre-harvest and / or post-harvest treatments; ii) Lawns and gardens, including specialist turf; iii) Forestry; iv) General disinfection area.

20. Use according to the preceding claims as a fungicide and / or as a bactericide, preferably as a fungicide.

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