Technical field

The present invention relates to a synergistic combination and to a composition for use as an acaricide, insecticide, pupicide and/or larvicide adapted to be placed in environments frequented by man and by animals (domestic and others), confined and not confined, which is particularly adapted to suppress juvenile stages of mosquitoes.

Background Art

The generic term mosquitoes is used to refer to many insects that belong to the order Diptera, suborder Nematocera, family Culicidae. This family comprises 35 genera and no less than 2700 species.

The larvae are always aquatic, whereas the adults are winged and subaerial. The buccal apparatus is lapping in the males, which feed on plant essences, and is stinging-sucking in the females, which in many species are hematophages, i.e., they feed on blood.

In the species that spawn in water, the mosquito rests on the surface of the water (which therefore must be still) to lay up to approximately 500 eggs.

An elongated legless larva covered with bristels is born from the eggs and lives exclusively underwater, moving toward the surface to breathe by means of a siphon (e.g., the Culex and Aedes genera) or a spiracular plate (e.g., the Anopheles genus) located in the terminal part (abdomen) of the body. The larvae feed on zooplankton, which they convey toward their mouth by the circular movements of their mouthbrushes. All mosquitoes have 4 larval stages.

After a period that varies from a few days to a few weeks, depending on the temperature, they pass to the pupal stage. Pupae live stably near the surface of the water in order to extract oxygen from the air by means of two structures arranged near their heads. An exception are the pupae of Mansonia richardii, which live underwater at all times and obtain oxygen from aquatic plants by means of a modified siphon that is driven into the aerenchyma of the plants.

Most existing insecticides are based on active ingredients that are unquestionably effective but are characterized by certain degrees of toxicity also for man and animals.

Suppression of mosquito larvae and pupae therefore entails a great risk of poisoning for fish and other inhabitants of bodies of water in which insecticides are spread, and problems can arise for man if he uses such water for various purposes (for example, irrigation).

Among insecticides that have a lower toxicity risk, the use of the following should be noted: Bacillus thuringensis (israelensis), Bacillus sphaericus, Bacillus subtilis (with their different varieties and subspecies), some mycetes such as those of the genus Lagenidium, Coelomyces and others (Beauveria, Entomophthora, Culicinomyces, Metarhizium, etcetera), of diatomaceous earth and its derivates. These substances are normally used in the fight against noxious arthropods and can be considered known active ingredients.

Whereas diatomaceous earth, mainly constituted by silicon and calcium, performs an undifferentiated pesticidal action, preparations based on Bacillus and such the above-mentioned mycetes perform more selective actions and have been studied for the production of specific biological products with low environmental impact.

In the anti-larval fight against mosquitoes, the latter two are in widespread use all over the world, particularly Bacillus thuringensis (israelensis) (BT) and Lagenidium. Both, however, perform their action as biocides against stage I, stage II and stage III larvae and have no incident action on stage IV larvae and, above all, on pupae. This has caused the need for more frequent treatments, which in any case are never capable of preventing the hatching of the adult insects. Considering that in just 5 days the eggs of Aedes albopictus, at the temperature of 29-30°C, hatch and produce larvae that mature up to stage IV, it is evident how frequent the treatments would have to be to prevent the hatching of the adults: every 3 days.

In reality, these treatments are performed usually about every 20 days, a period that is more than sufficient for adult mosquitoes to emerge and lay eggs and for the larvae of the next generation to hatch.

Although it is possible to combine these treatments with the use of adulticides, eradication of this insect in an area has never been achieved. Disclosure of the Invention

The aim of the present invention is to provide a synergistic combination and a composition for use as an acaricide, insecticide, pupicide and/or larvicide with substantially negligible toxicity for animals, in particular fish, and for man.

Within this aim, an object of the present invention is to provide a synergistic combination and a composition for use as an acaricide, insecticide, pupicide and/or larvicide adapted to act effectively also on stage IV larvae and on pupae of mosquitoes and/or of other arthropods.

Another object of the present invention is to provide a synergistic combination and a composition for use as an acaricide, insecticide, pupicide and/or larvicide that has low costs, is relatively easy to provide in practice and is safe in application.

This aim and these and other objects which will become better apparent hereinafter are achieved by a synergistic combination for use as an acaricide, insecticide, pupicide and/or larvicide, characterized in that it comprises at least one active ingredient A and at least one substance B,

said active ingredient A being selected from the group consisting of bacteria, bacterial toxins, fungi, plant derivatives and mineral derivatives; said substance B being selected from the group consisting of fatty alcohols, fatty acid esters, esters of alcohols and oils, wherein the active ingredient A and the substance B may be administered simultaneously, sequentially and separately.

This aim and these objects are also achieved by a composition for use as an acaricide, insecticide, pupicide and/or larvicide, characterized in that it comprises the synergistic combination of at least one active ingredient A and at least one substance B,

said active ingredient A being selected from the group consisting of bacteria, bacterial toxins, fungi, plant derivatives and mineral derivatives; said substance B being selected from the group consisting of fatty alcohols, fatty acid esters, esters of alcohols and oils.

Brief description of the drawings

Further characteristics and advantages of the invention will become better apparent from the following detailed description of a preferred but not exclusive embodiment of the synergistic combination and of the composition for use as acaricide, insecticide, pupicide and/or larvicide, according to the invention, given hereafter.

The present invention relates to the synergistic combination for use as an acaricide, insecticide, pupicide and/or larvicide that comprises at least one active ingredient A and at least one substance B.

In particular, the active ingredient A is selected from the group consisting of bacteria, bacterial toxins, fungi, plant derivatives and mineral derivatives.

The substance B is selected from the group consisting of fatty alcohols, fatty acid esters, esters of alcohols and oils.

It should be specified that the active ingredient A and the substance B may be administered simultaneously, sequentially and separately.

This means that the active ingredient A and the substance B may be administered to the environment to be decontaminated simultaneously (for example, a single product that comprises both) but also at different times, with different frequencies: in each case of separate administration, the synergistic effect of the active ingredient A and of the substance B shall be considered to be comprised within the protective scope of the present invention.

In particular, the present document relates to a composition for use as an acaricide, insecticide, pupicide and/or larvicide, which comprises the synergistic combination of at least one active ingredient A and at least one substance B.

It should be specified that the bacteria and the bacterial toxins that belong to the group of the active ingredient A are preferably selected among Bacillus thuringensis (israelensis), Bacillus sphaericus, Bacillus subtilis and their different varieties and subspecies.

The fungi (mycetes) that belong to the group of the active ingredient A are preferably selected among those of the genus Lagenidium, Coelomyces, Beauveria, Entomophthora, Culicinomyces, Metarhizium and their different varieties and subspecies.

The plant derivatives and the mineral derivatives that belong to the group of the active ingredient A are preferably selected among diatomaceous earths, fossil diatomaceous earths, silicon dioxide and their derivatives.

The fatty alcohols that belong to the group of the substance B comprise substances such as cetyl alcohol.

The fatty acid esters that belong to the group of the substance B comprise substances such as isopropyl palmitate.

The alcohol esters that belong to the group of the substance B comprise substances such as cetyl palmitate.

The oils that belong to the group of the substance B comprise substances such as coconut oil, castor oil, argan oil.

Both the synergistic combination and the composition according to the invention may comprise, moreover, at least one excipient, preferably selected among water, glycerin, vaseline, essential oils, oils, polymers, thickening agents and emulsifiers.

It is specified that the thickening agents and the emulsifiers are preferably selected among alginic acid, sodium alginate, potassium alginate, ammonium alginate, calcium alginate, 1 ,2-propanediol alginate, agar-agar, carrageenan, carob seed flour, guar gum, tragacanth, acacia gum also known as arabic gum, xanthan gum, karaya gum, tara gum, gellan gum, sorbitol, mannitol, glycerol, polyoxyethylene stearate, polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monooleate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan tristearate, pectins, ammonium phosphates, sucrose acetate isobutyrate, glycerol esters of wood rosin, cellulose, methylcellulose, hydroxy-propyl-cellulose, hydroxy-propyl-methylcellulose, ethyl methyl cellulose, carboxymethylcellulose, sodium salts, potassium salts, calcium salts of fatty acids, magnesium salts of fatty acids, mono- and diglycerides of fatty acids, acetic esters of mono- and diglycerides of fatty acids, lactic esters of mono- and diglycerides of fatty acids, citric esters of mono- and diglycerides of fatty acids, tartaric esters of mono- and diglycerides of fatty acids, mono- and diacetyl tartaric esters of mono- and diglycerides of fatty acids, mixed acetic-tartaric esters of mono- and diglycerides of fatty acids, sucrose esters of fatty acids, sucroglycerides, polyglycerol esters of fatty acids, polyglycerol polyricinoleate, 1 ,2- propanediol esters of fatty acids, reaction products of thermally oxidized soybean oil and mono- and diglycerides of fatty acids, sodium stearoyl-2- lactylate, calcium stearoyl-2-lactylate, stearyl tartrate, sorbitan monostearate, sorbitan tristearate, sorbitan monolaurate, sorbitan monoleate, sorbitan monopalmitate, disodium diphosphate, triphosphates, polyphosphates.

According to a particular embodiment of particular practical and applicative interest, the synergistic combination and the composition may further comprise at least one component C preferably selected from salicylic acid, lactic acid, propylene glycol, ethyl alcohol, petrolatum, geraniol, lavender oil, plant extracts, phenoxyethanol, sodium bicarbonate, Tween 20, Tween 60, Tween 80.

From the point of view of production, it is noted that the active ingredient A, the substance B and the composition according to the invention may be formulated in the form of microencapsulates or with percentages by mass (or by volume) of microencapsulate (so as to extend their action or to reach larval stages of insects at the bottom of stagnant water).

From the point of view of the use of the synergistic combination and of the composition according to the invention, it is appropriate to specify that they can be distributed not only directly or with specific pumps, but also with adapted dispensers that release them gradually or at different times.

Moreover, it is specified that both the active ingredient A and the substance B may be used both in liquid form and as powders: accordingly, the synergistic combination and the composition according to the invention might also exist both in liquid form and in powder form.

Also for the purpose of application, the possibility is not excluded that the active ingredient A and the substance B (optionally with the addition of adapted excipients and of the component C) might be mixed at the time of use (for example, through a dispenser cap) or they might already be combined in a concentrated composition to be diluted at the time of use.

Tests performed with the above-mentioned active ingredients A, combined with substances B such as fatty alcohols like cetyl alcohol, or fatty acid esters like isopropyl palmitate or essential oils such as essential oil of peppermint, tangerine, grapefruit, lemon, basil, etcetera or simple oils such as coconut oil, castor oil, jojoba oil, almond oil, olive oil, neem oil, sesame oil, peanut oil, soybean oil, flax oil, macadamia oil, grape-seed oil, palm oil, karite oil, argan oil, Paulownia oil and others, have allowed the detection of different synergistic actions with the active ingredients A, in terms both of power and of breadth of the field of action.

At least one active ingredient A and at least one substance B (optionally with the addition of a component C and excipients) were combined, both when heated and when cold, so as to obtain homogeneous solutions or emulsions that were easily, albeit sometimes temporarily, miscible both in water and with the known active ingredient, which was tested separately on its own, at the same doses, as a sample for comparison.

Excellent and surprising results have been achieved with the above- mentioned compositions, which were all far superior in terms of effectiveness to those obtained with the active ingredient A in use taken alone or in its commercial formulation.

Consider, as an example, the composition of cetyl alcohol and BT, in which the latter is added cold and mixed to an aqueous solution in which the cetyl alcohol, glycerinated or not, has been dissolved by heat, thus causing the death of larvae and pupae of mosquitoes in about two hours. Again as an example, consider the above-mentioned formulation that contains Bacillus thuringensis (israelensis), in which the heated cetyl alcohol, dissolved in coconut oil, is emulsified in one liter of water, thus causing the death of the larvae and of the pupae of mosquitoes in four hours.

The synergistic combination of (or the composition constituted by) isopropyl palmitate and Bacillus thuringensis (israelensis) or of the latter with castor oil and cetyl alcohol is considered equally effective.

The same applies to the synergistic combination of (or the composition constituted by) cetyl alcohol with diatomaceous earth or with citrus essential oils.

The problem of the deposition of the active ingredient A and of the substance B has been solved by using some of the following thickening agents: alginic acid, sodium alginate, potassium alginate, ammonium alginate, calcium alginate, 1.2-propanediol alginate, agar-agar, carrageenan, carob seed flour, guar gum, tragacanth, acacia gum (arabic gum), xanthan gum, karaya gum, tara gum, gellan gum, sorbitol, mannitol, glycerol, polyoxyethylene stearate, polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monooleate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan tristearate, pectins, ammonium phosphates, sucrose acetate isobutyrate, glycerol esters of wood rosin, cellulose, methylcellulose, hydroxy-propyl-cellulose, hydroxy-propyl-methylcellulose, ethyl methyl cellulose, carboxymethylcellulose, sodium salts, potassium salts and calcium salts of fatty acids, magnesium salts of fatty acids, mono- and diglycerides of fatty acids, acetic esters of mono- and diglycerides of fatty acids, lactic esters of mono- and diglycerides of fatty acids, citric esters of mono- and diglycerides of fatty acids, tartaric esters of mono- and diglycerides of fatty acids, mono- and diacetyl tartaric esters of mono- and diglycerides of fatty acids, mixed acetic-tartaric esters of mono- and diglycerides of fatty acids, sucrose esters of fatty acids, sucroglycerides, polyglycerol esters of fatty acids, polyglycerol polyricinoleate, 1.2- propanediol esters of fatty acids, reaction products of thermally oxidized soybean oil and mono- and diglycerides of fatty acids, sodium stearoyl-2- lactylate, calcium stearoyl-2-lactylate, stearyl tartrate, sorbitan monostearate, sorbitan tristearate, sorbitan monolaurate, sorbitan monoleate, sorbitan monopalmitate, disodium diphosphate (used only as raising agents), triphosphates, polyphosphates.

Some of these substances have been used and chosen differently in relation to the type of composition and to the concentration of the emulsion.

The diatomaceous earth and its derivatives may be formulated in different concentrations and with different excipients and/or emulsifiers and/or thickening agents, which have the role of preventing their deposition.

For this purpose, glucomannan is preferably used, which allows the microscopic particles to remain in suspension, making the emulsion more effective.

The composition obtained from the combination of the fibers of glucoxanthan, appropriately glycerinated cetyl alcohol and the microscopic fragments of fossil diatoms, emulsified with the right dose of polysorbate, is particularly effective even against the winged stages of many insects, in particular flies and mosquitoes. This formulation, therefore, has a dual range of action: the larval and pupal stages of mosquitoes and the adult stage. It can be used where vigorous decontamination, intended to eradicate mosquitoes in a given area, such as swamps, marshes, drain sewers, manholes etcetera, is necessary.

The cited composition, modified in its doses and, where necessary, with the optional addition of other components such as some essential oils (e.g., camphor oil), is active even against beetle larvae (even against the pupal stages) and parasitic and free-living mites, as well as for most animal ectoparasites (Mallophaga, Anoplura, etcetera).

Particularly concentrated solutions can be used, due to the capacity of diatomaceous earth to deposit, to kill the larval stages of Chironomidae and other insects, the larvae of which grow in mud. In this case the product, which is specially formulated, may be deposited directly in the mud at the bottom of insalubrious ponds and marshes.

Its use is particularly useful in countries with malaria, thanks to its particular and specific effectiveness against Anopheles both at the larval and the pupal stage.

Dispensing of the composition, optionally diluted, might occur by direct pouring, by atomization, micronization, but also by spreading by means of adapted devices (for example slow-release floats).

The active ingredient A might be combined with the substance B and with the excipients in the concentrated emulsion or instead at the time of use, by means of particular devices (e.g., a dispensing cap) or more simply by means of appropriately adapted bags (soluble and/or non-soluble). It is clear, therefore, that the active ingredients A can be enhanced by the synergistic addition of a substance B, such as for example cetyl alcohol or other fatty alcohols or isopropyl palmitate or other fatty acid esters or alcohols or even oils, either essential oils such as, for example, essential oil of tangerine, grapefruit, lemon or mint, or of simple oils such as coconut oil, castor oil, argan oil, macadamia oil or others.

Therefore, the invention to which the present patent relates achieves its aim, i.e., to enhance the effects of its individual components, thanks to a surprising synergistic effect that makes it possible to obtain a very strong suppression of the species that is the target of the decontamination, by using active ingredients A and a substance B that are not toxic for man and animals in general (their effect is focused on the target species).

All the compositions, comprising the active ingredient A and the substances B cited herein, such as synergistic agents, coformulants, excipients, thickening agents, emulsifiers or others, that contribute, in different combinations, to enhance the effect of the active ingredients A are within the scope of protection of the appended claims.

The invention thus conceived is susceptible of numerous modifications and variations, all of which are within the scope of the appended claims; all the details may further be replaced with other technically equivalent elements.

In the exemplary embodiments shown, individual characteristics, given in relation to specific examples, may actually be interchanged with other different characteristics that exist in other exemplary embodiments.

Moreover, it is noted that anything found to be already known during the patenting process is understood not to be claimed and to be the subject of a disclaimer.

In practice, the materials used, as well as the dimensions, may be any according to requirements and to the state of the art.

The disclosures in Italian Patent Application No. BO2009A000582 from which this application claims priority are incorporated herein by reference.