Use of α-ethylidene-phenylacetaldehyde for repelling mosquitoes

Abstract

The present invention discloses the use of α-ethylidene-phenylacetaldehyde for repelling mosquitoes. Specifically, the present invention provides any one of the following uses (i) to (ii) of α-ethylidene-phenylacetaldehyde or its tautomer or cis-trans isomer: (i) the use for repelling mosquitoes; (ii) the use in preparing a composition for repelling mosquitoes or a product for repelling mosquitoes. The present invention discovers that α-ethylidene-phenylacetaldehyde has a significant effect on repelling mosquitoes. By placing α-ethylidene-phenylacetaldehyde around the environment or applying α-ethylidene-phenylacetaldehyde as a potent mosquito repellent, mosquito bites can be prevented.

Description

Technical Field

[0001] The present invention belongs to the technical field of mosquito repellents and relates to the use of α-ethylidene-phenylacetaldehyde for repelling mosquitoes. Background Art

[0002] Mosquitoes belong to the order Diptera and the family Culicidae. They are widely distributed and rich in species, and are the most important group of medical insects. Mosquitoes are divided into three important genera, namely Anopheles, Culex, and Aedes. Mosquitoes can not only bite humans and animals, but also carry and transmit hundreds of viruses, such as dengue fever, Zika, chikungunya, encephalitis, etc. Mosquito-borne infectious diseases have become the main part of human vector-borne infectious diseases. According to the statistics of the World Health Organization, at present, more than 100 countries and regions have seen the prevalence of mosquito-borne virus infections, and approximately 2.5 billion people live in areas threatened by mosquito-borne virus infections. In recent years, the prevalence trend of mosquito-borne viruses has intensified globally, and it has become a worldwide public health problem.

[0003] Aedes is a kind of insect belonging to the genus Aedes in the subfamily Culicinae of the family Culicidae. Mosquitoes of the genus Aedes are generally called Aedes mosquitoes. They are distributed all over the world and are the largest genus in the family Culicidae. Aedes mosquitoes can spread many diseases and pose a threat to human health. Diseases such as yellow fever and dengue fever are mainly transmitted by Aedes mosquitoes. Aedes mosquitoes are also the main culprits for the transmission of the Zika virus. Mosquito species proven to be vectors of dengue fever include Aedes aegypti, Aedes albopictus, Aedes polynesiensis, etc. Among them, Aedes aegypti is a kind of insect that obtains and transmits viruses by sucking blood. The arboviruses transmitted by it can be divided into the families Flaviviridae, Togaviridae, and Bunyaviridae, etc. The viruses transmitted by mosquitoes will show clinical symptoms such as encephalitis, meningitis, and hemorrhagic fever, resulting in hundreds of millions of infections and hundreds of thousands of death cases every year, causing serious harm to world public health.

[0004] α-Ethylidene-phenylacetaldehyde, also known as 2-phenyl-2-butenal, is a permitted synthetic flavor for food according to the Food Additive Use Standard GB2760-2014. However, there is no relevant research and report on the role of α-ethylidene-phenylacetaldehyde in repelling mosquitoes. Summary of the Invention

[0005] Problems to be Solved by the Invention

[0006] The present invention discovers that a known compound, α-ethylidene-phenylacetaldehyde, has significant mosquito-repellent efficacy and can be used as an active ingredient of a new and highly effective mosquito repellent.

[0007] Solutions for Solving the Problems

[0008] The first aspect of the present invention provides any one of the following (i) to (ii) uses of α-ethylidene-phenylacetaldehyde or its tautomer, cis-trans isomer:

[0009] (i) Use for mosquito repellent;

[0010] (ii) Use in the preparation of a composition for mosquito repellent or a product for mosquito repellent.

[0011] In some embodiments, the mosquitoes include one or more of Culex, Culiseta, Anopheles, and Aedes.

[0012] In some embodiments, the mosquito is Aedes, which includes one or more of Aedes aegypti, Aedes albopictus, Aedes polynesiensis, Aedes australis, Aedes cinereus, Aedes rusticus, and Aedes vexans.

[0013] In some embodiments, the composition for mosquito repellent contains a carrier and / or an excipient.

[0014] In some embodiments, the product for mosquito repellent is a mosquito repellent, a mosquito repellent patch, a mosquito repellent cream, a mosquito repellent ointment, a mosquito repellent hair care product, or a mosquito repellent air freshener.

[0015] In some embodiments, the object to which the composition for mosquito repellent or the product for mosquito repellent is applied is a human, an animal, a three-dimensional space, or an object surface.

[0016] In some embodiments, the composition for mosquito repellent or the product for mosquito repellent is administered or packaged in a unit dose.

[0017] In some embodiments, the unit dose contains 0.001 mg to 20 mg of α-ethylidene-phenylacetaldehyde or its tautomer, cis-trans isomer, preferably 0.01 mg to 15 mg of α-ethylidene-phenylacetaldehyde or its tautomer, cis-trans isomer, more preferably 0.1 mg to 10 mg of α-ethylidene-phenylacetaldehyde or its tautomer, cis-trans isomer.

[0018] The second aspect of the present invention provides a composition for mosquito repellent or a product for mosquito repellent, which contains α-ethylidene-phenylacetaldehyde or its tautomer, cis-trans isomer as an active ingredient for mosquito repellent.

[0019] The third aspect of the present invention provides a method for mosquito repellent, which includes administering an effective amount of α-ethylidene-phenylacetaldehyde or its tautomer, cis-trans isomer, or the composition for mosquito repellent or the product for mosquito repellent described in the second aspect of the present invention to an object.

[0020] Effects of the Invention

[0021] The present invention discovers that α-ethylidene-phenylacetaldehyde (a known food flavoring (aromatic enhancer), molecular formula: C 10 H 10 O, molecular weight: 146.19) has a significant effect of repelling mosquitoes (e.g., Aedes aegypti). By placing α-ethylidene-phenylacetaldehyde around the environment or applying α-ethylidene-phenylacetaldehyde as a potent mosquito repellent, mosquito bites can be prevented. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1A It is a schematic diagram of the experimental process of Example 1.

[0023] Figure 1B It is a schematic diagram of the experimental results of Example 1.

[0024] Figure 2A It is a schematic diagram of the experimental process of Example 2.

[0025] Figure 2B It is a schematic diagram of the experimental results of Example 2. DETAILED DESCRIPTION OF THE INVENTION

[0026] The following will detail various exemplary embodiments, features, and aspects of the present invention. The word "exemplary" used here means "serving as an example, embodiment, or illustrative". Any embodiment described as "exemplary" here does not necessarily have to be construed as superior or better than other embodiments.

[0027] In addition, for a better illustration of the present invention, numerous specific details are given in the following detailed description. Those skilled in the art should understand that the present invention can also be implemented without some specific details. In other instances, methods, means, equipment, and steps well-known to those skilled in the art are not described in detail to highlight the gist of the present invention.

[0028] Unless otherwise stated, the units used in this specification are all international standard units, and the numerical values and numerical ranges appearing in the present invention should be understood to include the systematic errors inevitable in industrial production.

[0029] In this specification, the meaning expressed by using "can" includes both the meaning of performing a certain process and the meaning of not performing a certain process.

[0030] In this specification, the "some specific / preferred embodiments", "other specific / preferred embodiments", "embodiments", etc. mentioned refer to the specific elements (e.g., features, structures, properties, and / or characteristics) related to the embodiment, which are included in at least one of the embodiments described herein, and may or may not be present in other embodiments. Additionally, it should be understood that the elements may be combined in any suitable manner in various embodiments.

[0031] In this specification, the numerical range expressed as "numerical value A to numerical value B" refers to the range that includes the endpoint numerical values A and B.

[0032] In this specification, "optional" or "optionally" means that the subsequent described event or situation may or may not occur, and this description includes the situation where the event occurs and the situation where the event does not occur.

[0033] The terms "comprise" and "have" and any variations thereof in the present invention are intended to cover non-exclusive inclusion. For example, a process, method, device, product, or equipment that includes a series of steps is not limited to the listed steps or modules, but optionally further includes steps not listed, or optionally further includes other steps inherent to these processes, methods, products, or equipment.

[0034] In the present invention, "a plurality of" refers to two or more. "And / or" describes the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. The character " / " generally represents an "or" relationship between the associated objects before and after.

[0035] In this specification, the term "host" refers to any plant or animal susceptible to insects (e.g., mosquitoes). Generally, a host is considered to be a food source or living environment acceptable to insects (e.g., mosquitoes).

[0036] In this specification, the term "mosquito-sensitive product" refers to any man-made commodity susceptible to mosquitoes. It may include buildings, furniture, etc. Generally, such a product is considered to be a food source or living environment acceptable to mosquitoes.

[0037] In the present invention, the term "tautomer" (or "tautomeric form") refers to structural isomers with different energies that can be interconverted through a low energy barrier. If tautomerism is possible (e.g., in solution), a chemical equilibrium of tautomers can be achieved. For example, proton tautomers (or proton-transfer tautomers) include (but are not limited to) interconversions through proton migration, such as keto-enol isomerization, imine-enamine isomerization, amide-imino alcohol isomerization, etc. Unless otherwise specified, all tautomeric forms of the compounds of the present invention are within the scope of the present invention.

[0038] In the present invention, the term "cis-trans isomer" refers to stereoisomers formed by atoms (or groups) on both sides of a double bond or a ring system due to their different positions relative to a reference plane; in the cis isomer, the atoms (or groups) are on the same side of the double bond or the ring system, and in the trans isomer, the atoms (or groups) are on the opposite sides of the double bond or the ring system. Unless otherwise specified, all cis-trans isomer forms of the compounds of the present invention are within the scope of the present invention.

[0039] The technical solutions of the present invention are specifically described below.

[0040] <Use of α-Ethylidene-phenylacetaldehyde>

[0041] The present invention discovers that α-ethylidene-phenylacetaldehyde or its tautomers and cis-trans isomers have excellent mosquito repellent effects. Therefore, in one aspect, the present invention provides the use of α-ethylidene-phenylacetaldehyde or its tautomers and cis-trans isomers for mosquito repellent. In another aspect, the present invention provides the use of α-ethylidene-phenylacetaldehyde or its tautomers and cis-trans isomers in the preparation of a composition for mosquito repellent or a product for mosquito repellent.

[0042] In some embodiments, α-ethylidene-phenylacetaldehyde, also known as 2-phenyl-2-butenal, has the molecular formula C 10 H 10 O, its CAS No. is 4411-89-6, its molecular weight is 146.19, and its structural formula is shown as the following formula (I):

[0043]

[0044] In some embodiments, "mosquito" or "mosquitoes" refers to insects of the family Culicidae. The mosquitoes of the present invention may include adult mosquitoes, mosquito larvae, pupae or their eggs. Generally, the life cycle of a mosquito includes four independent and distinct stages: egg, larva, pupa and adult. Thus, when the eggs are placed on the surface of water (e.g., Culex, Culiseta and Anopheles) or on flooded moist soil (e.g., Aedes), the life cycle of the mosquito begins. Most eggs hatch into larvae within 48 hours. The larvae live in water, feed on microorganisms and organic matter, and then come to the surface to breathe. They will molt four times, growing larger each time, and when they molt for the fourth time, the larvae turn into pupae. The pupa stage is a resting stage, a non-feeding stage of about two days. At this time, the mosquito becomes an adult. When development is complete, the pupal skin ruptures and the adult mosquito emerges.

[0045] In some embodiments, the mosquito belongs to one or more of the subfamilies Anophelinae and Culicinae. In some specific embodiments of the present invention, the mosquito includes one or more of Culex, Culiseta, Anopheles and Aedes.

[0046] In some more specific embodiments of the present invention, the mosquito includes, but is not limited to, Aedes, such as: one or more of Aedes aegypti, Aedes albopictus, Aedes polynesiensis, Aedes australis, Aedes cinereus, Aedes rusticus, Aedes vexans. In some preferred embodiments of the present invention, the mosquito is Aedes aegypti.

[0047] In some embodiments, the α-ethylidene-phenylacetaldehyde or its tautomer, cis-trans isomer is used as an active ingredient for repelling mosquitoes in a composition for repelling mosquitoes or a product for repelling mosquitoes.

[0048] In some specific embodiments, the α-ethylidene-phenylacetaldehyde or its tautomer, cis-trans isomer can be used as a single active ingredient for repelling mosquitoes in the composition for repelling mosquitoes or the product for repelling mosquitoes. In some other specific embodiments, the composition for repelling mosquitoes or the product for repelling mosquitoes may also contain other substances having mosquito-repellent effects.

[0049] In this specification, "composition for repelling mosquitoes", "product for repelling mosquitoes", etc. refer to compounds or compositions that can prevent mosquitoes from approaching their preferred hosts or suitable articles. Most known "compositions for repelling mosquitoes" or "products for repelling mosquitoes" are not active poisons, but are only used to prevent damage to plants / animals or various articles by making the mosquito food source or living environment less attractive or repulsive. Generally, "compositions for repelling mosquitoes", "products for repelling mosquitoes" are applied topically to the host or incorporated into mosquito-sensitive articles to obtain a mosquito-repellent article that can prevent mosquitoes from approaching the three-dimensional space where the host or article is located. In another scenario, the effect of "compositions for repelling mosquitoes", "products for repelling mosquitoes" is to drive mosquitoes away or repel: 1) the host, so as to minimize the frequency of mosquitoes "biting" the host; or 2) mosquito-sensitive articles, so as to protect the articles from being damaged by mosquitoes.

[0050] In some embodiments, the composition for repelling mosquitoes can be in any suitable form, for example, in various forms such as liquid, solid, semi-solid, gas, etc. The α-ethylidene-phenylacetaldehyde or its tautomer, cis-trans isomer can be made into solutions, sprays, aerosols, emulsions, suspensions, ointments, gels, patches and other suitable forms with conventional non-toxic carriers and / or excipients acceptable in pharmaceutical or daily chemical products.

[0051] The carriers and / or excipients include, for example, water, ethanol, propylene glycol, jojoba oil, gelatin, gum arabic, Tween 80, glyceryl stearate, glyceryl trioctanoate, cetyl alcohol, lanolin, urea, petrolatum, stearyl alcohol, beeswax, polyoxyethylene oleyl ether, and also include other carriers and / or excipients suitable for use in the preparation of preparations in liquid, solid, semi-solid, gas forms, etc. The composition for repelling mosquitoes can additionally contain stabilizers, thickeners, colorants and / or fragrances.

[0052] The product for repelling mosquitoes in the present invention can be a liquid, an ointment, a pendant or a convenient sticker. The product for repelling mosquitoes in the present invention can be a cosmetic. In the present invention, cosmetics refer to daily chemical industrial products that are applied to any part of the human body surface (such as skin, hair, nails, lips, etc.) by means of rubbing, spraying or other similar methods to achieve cleaning, eliminating bad odors, skin care, beauty and decoration. The product for repelling mosquitoes in the present invention can be a leave-on cosmetic or a rinse-off cosmetic.

[0053] The product for repelling mosquitoes in the present invention can be a mosquito repellent (such as an oil-based preparation, an alcohol-based preparation, a water-based preparation), or can also be a mosquito repellent sticker, a mosquito repellent cream, a mosquito repellent ointment, a mosquito repellent hair care product, a mosquito repellent air freshener, etc.

[0054] In some specific embodiments, the product for repelling mosquitoes is a mosquito repellent, and the mosquito repellent is an oil-based preparation, with α-ethylidene-phenylacetaldehyde or its tautomer, cis-trans isomer as the active ingredient. Exemplarily, it can be supplemented with vegetable oil, etc.

[0055] In some specific embodiments, the product for repelling mosquitoes is a mosquito repellent, and the mosquito repellent is an alcohol-based preparation, with α-ethylidene-phenylacetaldehyde or its tautomer, cis-trans isomer as the active ingredient. Exemplarily, it can be supplemented with ethanol and water, etc.

[0056] In some specific embodiments, the product for repelling mosquitoes is a mosquito repellent, and the mosquito repellent is a water-based preparation, with α-ethylidene-phenylacetaldehyde or its tautomer, cis-trans isomer as the active ingredient. Exemplarily, it can be supplemented with gelatin, gum arabic, deionized water, etc.

[0057] In some specific embodiments, the product for repelling mosquitoes is a mosquito repellent patch, and the mosquito repellent patch uses α-ethylidene-phenylacetaldehyde or its tautomer, cis-trans isomer as the active ingredient. Exemplarily, it can be combined with a polymer gel matrix and made into a mosquito repellent patch using microdroplet coating and constant-rate sustained release control technology.

[0058] In some specific embodiments, the product for repelling mosquitoes is a mosquito repellent patch, and the mosquito repellent patch uses α-ethylidene-phenylacetaldehyde or its tautomer, cis-trans isomer as the active ingredient. Exemplarily, paper or woven or non-woven materials can be used as the substrate. For example, when using non-woven materials as the substrate, it is an elastic sheet containing adhesive or thermally bonded fibers. The fibers can be selected from cellulose esters, cotton, hemp, jute, flax, ramie, rayon, polyamides, polyesters, polyolefins, polypropylene, polyethylene derivatives, silk, sisal, and wool and their combinations.

[0059] <Composition for mosquito repellent or product for mosquito repellent>

[0060] On the other hand, the present invention provides a composition for mosquito repellent or a product for mosquito repellent, which contains α-ethylidene-phenylacetaldehyde or its tautomer, cis-trans isomer as the active ingredient for mosquito repellent.

[0061] In some specific embodiments, α-ethylidene-phenylacetaldehyde or its tautomer, cis-trans isomer can be used as the single active ingredient for mosquito repellent in the composition for mosquito repellent or the product for mosquito repellent. In some other specific embodiments, the composition for mosquito repellent or the product for mosquito repellent may also contain other substances with mosquito repellent effects.

[0062] The form, usable carriers, and / or excipients, etc. of the composition for mosquito repellent or the product for mosquito repellent are as described in the previous <Use of α-ethylidene-phenylacetaldehyde>.

[0063] In some embodiments, α-ethylidene-phenylacetaldehyde or its tautomer, cis-trans isomer, a composition for repelling mosquitoes containing the same, or a product for repelling mosquitoes of the present invention can be administered or packaged in unit doses.

[0064] In the present specification, a unit dose refers to a physically discrete unit suitable as a unit dose for a mosquito-repelling target; each unit contains a predetermined amount of an active compound (α-ethylidene-phenylacetaldehyde or its tautomer, cis-trans isomer) calculated to produce the desired mosquito-repelling effect, as well as the required carrier and / or excipient.

[0065] In some specific embodiments, the unit dose contains 0.001 mg to 20 mg of α-ethylidene-phenylacetaldehyde or its tautomer, cis-trans isomer, preferably 0.01 mg to 15 mg of α-ethylidene-phenylacetaldehyde or its tautomer, cis-trans isomer, more preferably 0.01 mg to 10 mg of α-ethylidene-phenylacetaldehyde or its tautomer, cis-trans isomer, and further preferably 0.1 mg to 10 mg or 1 mg to 10 mg of α-ethylidene-phenylacetaldehyde or its tautomer, cis-trans isomer. For example, 1 mg, 2 mg, 3 mg, 4 mg, 5 mg, 6 mg, 7 mg, 8 mg, 9 mg, or 10 mg of α-ethylidene-phenylacetaldehyde or its tautomer, cis-trans isomer.

[0066] In some specific embodiments, the composition for repelling mosquitoes or the product for repelling mosquitoes provided by the present invention does not contain DEET, Icaridin, IR3535, etc. Among them, the chemical name of DEET is N,N-diethyl-3-methylbenzamide. The chemical name of Icaridin is 1-(1-methylpropoxycarbonyl)-2-(2-hydroxyethyl)piperidine, which is one of the most effective mosquito repellents known in addition to DEET. IR3535 is also known as ethyl butylacetylaminopropionate, and its chemical name is 3-(N-butyl-N-acetyl)-aminopropionic acid ethyl ester, abbreviated as ethyl butylacetylaminopropionate.

[0067] <Method for repelling mosquitoes>

[0068] This application also relates to a method for repelling mosquitoes, including administering an effective amount of α-ethylidene-phenylacetaldehyde or its tautomer, cis-trans isomer, or the composition for repelling mosquitoes of the present invention, or the product for repelling mosquitoes of the present invention to a target.

[0069] In some embodiments, the target can be a human or an animal target. In some specific embodiments, the animal can be a rodent, such as a mouse or a rat. In some specific embodiments, the animal can be a companion animal or a farm animal.

[0070] When the object is a human or animal object, the application method can be topical application to the skin, hair or fur surface of the human or animal object.

[0071] In other embodiments, the object can be a three-dimensional space or any object surface, such as a room, a clothing surface, etc., but not limited thereto.

[0072] When the object is a three-dimensional space or any object surface, the application method can be, for example, atomization, brushing, coating, immersion bathing, soaking, dropping, powder spraying, foaming, perfusion, injection onto or into it, pouring, roller coating, dispersion, spraying, spreading, spraying or wiping onto at least a part of the object, so that α-ethylidene-phenylacetaldehyde or its tautomer, cis-trans isomer, or α-ethylidene-phenylacetaldehyde or its tautomer, cis-trans isomer in the mosquito repellent composition of the present invention or the mosquito repellent product of the present invention can be released.

[0073] In the present invention, the term "release" means that α-ethylidene-phenylacetaldehyde or its tautomer, cis-trans isomer is released into the atmosphere (for example, around an object, such as a human, an animal, a three-dimensional space, an object surface, etc.). "Release" can be active release or passive release (for example, leaving α-ethylidene-phenylacetaldehyde or its tautomer, cis-trans isomer or the mosquito repellent composition containing it or the mosquito repellent product of the present invention stationary in a three-dimensional space).

[0074] In some embodiments, a unit dose of α-ethylidene-phenylacetaldehyde or its tautomer, cis-trans isomer, or the mosquito repellent composition of the present invention, or the mosquito repellent product of the present invention is applied to an object.

[0075] In some specific embodiments, the unit dose contains 0.001 mg to 20 mg of α-ethylidene-phenylacetaldehyde or its tautomer, cis-trans isomer, preferably 0.01 mg to 15 mg of α-ethylidene-phenylacetaldehyde or its tautomer, cis-trans isomer, more preferably 0.01 mg to 10 mg of α-ethylidene-phenylacetaldehyde or its tautomer, cis-trans isomer, and further preferably 0.1 mg to 10 mg or 1 mg to 10 mg of α-ethylidene-phenylacetaldehyde or its tautomer, cis-trans isomer. For example, 1 mg, 2 mg, 3 mg, 4 mg, 5 mg, 6 mg, 7 mg, 8 mg, 9 mg or 10 mg of α-ethylidene-phenylacetaldehyde or its tautomer, cis-trans isomer.

[0076] Examples

[0077] The embodiments of the present invention will be described in detail below in conjunction with examples. However, those skilled in the art will understand that the following examples are only used to illustrate the present invention and should not be construed as limiting the scope of the present invention. For those conditions not specified in the examples, they are carried out according to conventional conditions or the conditions recommended by the manufacturer. For the reagents or instruments without indicating the manufacturer, they are all conventional products that can be obtained through commercial purchase.

[0078] Experimental materials and apparatus

[0079] The Aedes aegypti used in the following examples was disclosed in the literature "Colpitts TM et al. Alterations in the Aedes aegypti Transcriptome during Infection with West Nile, Dengue and Yellow Fever Viruses. 2011, PloS Pathog 7(9):e1002189." and the public can obtain it from the School of Medicine, Tsinghua University.

[0080] The dual-arm olfactometer was customized by Beijing Xusheng Hengye Shelf Co., Ltd. The specific parameters are as follows: the gas chamber (60×60×80 cm), the cylindrical mosquito trap (length 20 cm, inner diameter 10 cm), and the stimulus source release barrel (length 30 cm, inner diameter 15 cm) are connected in series.

[0081] The mosquito cage was customized by Beijing Xusheng Hengye Shelf Co., Ltd. The specific parameters are: 60 cm×60 cm.

[0082] α-Ethylidene-phenylacetaldehyde was purchased from Merck, product number: M69336.

[0083] Methanol was purchased from Sigma, product number: 646377.

[0084] Example 1. Determination of the mosquito repellent effect of α-ethylidene-phenylacetaldehyde by a dual-arm olfactometer

[0085] Rearing method of Aedes aegypti: The rearing conditions for female Aedes aegypti are a temperature of 26±2°C, a relative humidity of 70±5%, and a light cycle of 14 h:10 h (light:dark). Female Aedes aegypti 7-14 days after eclosion were selected for the experiment. Before the experiment, female and male mosquitoes mated but did not have a blood-sucking behavior.

[0086] Before the experiment, the Aedes aegypti were starved for 14-24 h.

[0087] In this example, a double-arm olfactory assay device was selected to measure the mosquito repellent effect of α-ethylidene-phenylacetaldehyde applied to the back of mice. All components of the double-arm olfactory assay device were made of acrylic material, and the air flow pipeline material was Teflon. The double-arm olfactory assay device consisted of an air chamber (60×60×80 cm), two cylindrical mosquito-catching buckets (20 cm in length and 10 cm in inner diameter) with a round hole (5 cm in inner diameter) at one end, and two stimulus source release buckets (30 cm in length and 15 cm in inner diameter) connected in series.

[0088] For mice, at the beginning of the experiment, 60 starved female mosquitoes were released into the air chamber to adapt to the air chamber environment for 10 min. α-Ethylidene-phenylacetaldehyde was dissolved in methanol and diluted to 0.1, 1, 10, 100 mg / mL. The control group was methanol solvent. After applying 100 μL to the mice, the experiment was carried out, with 3 mice in each group. Each time, 60 female mosquitoes were released for the behavioral response, and the experiment was repeated 3 times. Chi-square test was used for data analysis.

[0089] To avoid the influence of external vision and light intensity, the experiment on mice was carried out in an environment close to darkness. After 30 min, the number of female mosquitoes flying into the two cylindrical mosquito-catching buckets was counted. As mentioned above, each experiment was repeated three times, and all components of the double-arm olfactory assay device and the air flow pipeline were sprayed with 75% alcohol and dried thoroughly between each repetition.

[0090] The experimental results showed that when 1 mg of α-ethylidene-phenylacetaldehyde was applied, a 100% mosquito repellent effect could be achieved. In the 3 repeated experiments, the number of mosquitoes in the group treated with α-ethylidene-phenylacetaldehyde was 0, 0, 0; the number of mosquitoes in the group treated with the solvent was 22, 20, 22, showing a significant difference in mosquito repellent effect compared with the group treated with the solvent (control group). When 10 mg of α-ethylidene-phenylacetaldehyde was applied, a 100% mosquito repellent effect could also be achieved, and there was a significant difference in mosquito repellent effect compared with the group treated with the solvent (control group). When 0.01 mg and 0.1 mg of α-ethylidene-phenylacetaldehyde were applied, although a 100% mosquito repellent effect was not achieved, the mosquito repellent effects were significantly better than those of the control group compared with the group treated with the solvent (control group).

[0091] Example 2. Measuring the mosquito repellent effect of α-ethylidene-phenylacetaldehyde through a cage experimental device

[0092] In this example, the breeding method of Aedes aegypti was the same as that in Example 1.

[0093] To avoid the influence of mouse urine and feces on the preference of female Aedes aegypti, before the experiment, 0.75% sodium pentobarbital solution was injected intraperitoneally into the mice, and the experiment was carried out after they were anesthetized.

[0094] Dissolve α-ethylidene-phenylacetaldehyde in methanol and dilute it to 100 mg / mL. The control group is methanol solvent. After applying 100 μL to mice, conduct the experiment.

[0095] Apply α-ethylidene-phenylacetaldehyde (10 mg) to the back of mice. The control group of mice is applied with the corresponding solvent. Put two groups of mice (one mouse in each group) into a mosquito cage (60 cm × 60 cm) with 40 Aedes aegypti mosquitoes for 30 minutes. Count the proportion of the number of mosquitoes that bite the two groups of mice (the mouse applied with α-ethylidene-phenylacetaldehyde is not bitten. Count the proportion of the number of bitten mosquitoes to the total number of mosquitoes put into the mosquito cage, which is the proportion of the number of mosquitoes that bite the control group of mice). Repeat the experiment 3 times. The data analysis uses chi-square test.

[0096] Meanwhile, in order to test the mosquito repellent duration of α-ethylidene-phenylacetaldehyde, at the 0 hour (control group 15 / 40 = 37.5%; the mouse applied with α-ethylidene-phenylacetaldehyde is not bitten), 4 hours (control group 14 / 40 = 35%; the mouse applied with α-ethylidene-phenylacetaldehyde is not bitten), 6 hours (control group 14 / 40 = 35%; the mouse applied with α-ethylidene-phenylacetaldehyde is not bitten), 8 hours (control group 15 / 40 = 37.5%; the mouse applied with α-ethylidene-phenylacetaldehyde is not bitten), 24 hours (control group 14 / 40 = 35%; the mouse applied with α-ethylidene-phenylacetaldehyde is not bitten), 48 hours (control group 11 / 40 = 27.5%; the mouse applied with α-ethylidene-phenylacetaldehyde is not bitten) after applying α-ethylidene-phenylacetaldehyde (10 mg) to mice, count the proportion of mosquitoes biting the mice. The data analysis uses chi-square test.

[0097] The experimental results show that applying α-ethylidene-phenylacetaldehyde (10 mg) to mice can maintain the mosquito repellent effect within 48 hours. See Figure 2B , when applying α-ethylidene-phenylacetaldehyde (10 mg) to mice, for at least 48 hours, the proportion of being bitten by mosquitoes is 0%, while the proportion of being bitten by mosquitoes in the control group remains at 27.5% - 37.5%.

[0098] It should be noted that although the technical solutions of the present invention are introduced by specific examples, those skilled in the art can understand that the present invention should not be limited thereto.

[0099] The above have described the embodiments of the present invention. The above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and variations are obvious to those of ordinary skill in the art in the technical field without departing from the scope and spirit of the described embodiments. The choice of terms used herein is intended to best explain the principles of the embodiments, practical applications, or improvements to the technology in the market, or to enable other ordinary skilled persons in the technical field to understand the disclosed embodiments herein.

Claims

1. Use of α-ethylidene-phenylacetaldehyde in any one of the following (i) to (ii): (i) Use for mosquito repellent; (ii) Use in the preparation of a composition for mosquito repellent or a product for mosquito repellent; The mosquito is Aedes.

2. The use according to claim 1, wherein The Aedes includes one or more of Aedes aegypti, Aedes albopictus, Aedes polynesiensis, Aedes australis, Aedes cinereus, Aedes rusticus, and Aedes vexans.

3. The use according to claim 1 or 2, wherein The composition for mosquito repellent contains a carrier and / or an excipient.

4. Use according to claim 1 or 2, wherein, The product for mosquito repellent is a mosquito repellent, a mosquito repellent patch, a mosquito repellent cream, a mosquito repellent ointment, a mosquito repellent hair care product, or a mosquito repellent air freshener.

5. Use according to claim 1 or 2, wherein, The composition for mosquito repellent or the product for mosquito repellent is applied to a human, an animal, a three-dimensional space, or an object surface.

6. Use according to claim 1 or 2, wherein, The composition for mosquito repellent or the product for mosquito repellent is administered or packaged in a unit dose.

7. The use according to claim 6, wherein The unit dose contains 0.001 mg to 20 mg of α-ethylidene-phenylacetaldehyde.

8. The use according to claim 7, wherein, The unit dose contains 0.01 mg to 15 mg of α-ethylidene-phenylacetaldehyde.

9. The use according to claim 7, wherein The unit dose contains 0.1 mg to 10 mg of α-ethylidene-phenylacetaldehyde.

10. A method for mosquito repellent, which includes administering an effective amount of α-ethylidene-phenylacetaldehyde to an object, and the mosquito is Aedes.

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