EA039964B1 - ANTIMICROBIAL COMPOSITION CONTAINING ESSENTIAL OIL AND ANTIMICROBIAL LIPID - Google Patents

Description

(57) This invention relates to an antimicrobial composition, especially one that provides synergistic efficacy against dandruff or against acne. This is achieved by a judicious combination of selected active substances from essential oils selected from thymol or terpineol and certain antimicrobial lipids selected from sapienic acid, palmitoleic acid, sphingosine, dihydrosphingosine, phytosphingosine and 6-hydroxysphingosine. These compositions can be delivered with very many different types of personal care products, eg shampoo, conditioner; means for washing the face or hands; or no rinse cream/lotion.

The field of technology to which the invention belongs

This invention relates to an antimicrobial composition. More specifically, the invention relates to a composition for personal care, for example for hair, body, hands or face, which provides antimicrobial efficacy. In particular, it relates to a cleaning/care composition containing active substances that interact to provide synergistic antimicrobial efficacy to prevent or alleviate the manifestations of problems such as acne or dandruff.

Prior Art

The invention relates to an antimicrobial composition useful for cleaning and/or caring for any part of the body, but especially suitable for hair and scalp care, hand hygiene or facial care and cleaning.

Acne, also known as Acne vulgaris, is a common skin condition that affects almost all teenagers and/or adults at some point in life. It has a complex etiology, including abnormal keratinization, excess sebum production, androgenic function, bacterial growth, and immune hypersensitivity. Although one or more of the above processes is correlated with acne, the underlying trigger and exact sequence of events leading to acne formation is not fully understood. Another factor associated with acne is the presence of free radicals, followed by oxidative stress leading to cell damage. It is noted that acne usually occurs in areas rich in sebaceous glands, such as the face, neck and back. The bacterium Propionibacterium acne (P. acnes) has also been linked to acne.

Acne has been treated in a variety of ways. Most treatments take weeks to months before noticeable changes appear. Benzoyl peroxide, which has an antibacterial effect, is used for mild cases of comedones and is also believed to prevent the formation of other comedones. In very severe cases of acne, antibiotics such as tetracycline, erythromycin, and clindamycin have been used. Antibiotics are believed to work through several mechanisms, the most important of which is to reduce bacteria in and around the follicle. They are also thought to reduce irritating chemicals produced by white blood cells in sebum, thereby reducing the inflammatory response.

Washing hands with antimicrobial soap, especially after going to the toilet and/or before eating, has been identified as one of the most effective ways to reduce mortality, morbidity and improve the overall quality of life of people. Sanitizing and disinfecting soap compositions containing a chlorine-based antimicrobial agent such as triclosan are known. If a consumer uses soap with low or slow antimicrobial activity, the removal of bacteria from their skin may be relatively inadequate, which may contaminate other living and/or inanimate surfaces and lead to the spread of pathogens and subsequent diseases. Therefore, providing hand and body wash compositions with enhanced antimicrobial activity is of paramount importance in order to improve the health and quality of life of consumers.

Hair care compositions typically provide a cleansing or conditioning effect, or a combination of the two. Such compositions typically contain one or more cleansing surfactants, which generally help to cleanse the hair and/or scalp of unwanted dirt, particles and greasy substances.

In addition, an anti-dandruff effect has been provided by hair care compositions. Dandruff is a problem that affects many people all over the world. The condition is manifested by the separation of accumulations of dead cells from the scalp. They are white in color and provide an aesthetically pleasing appearance. A factor contributing to the appearance of dandruff is some representatives of the yeast Malassezia. To combat them, anti-dandruff products have been developed in the form of shampoos for washing hair. An example of a known anti-dandruff shampoo includes sodium lauryl ether sulfate (ethoxylated anionic surfactant) in combination with an anti-dandruff agent. Typical anti-dandruff agents used in hair care are metal pyrithione, eg, zinc pyrithione (ZPTO), Octopirox® (piroctone olamine), azole antimicrobials (eg, climbazole), selenium sulfide, and combinations thereof.

Most treatments for the above problems involve the use of synthetic chemicals. Many people choose not to use synthetic chemicals as they are believed to be harmful to the human body. Some people believe that synthetic chemicals cause side effects. Consequently, more and more people are choosing to use materials that are natural, such as herbal actives.

Although the aforementioned problems are largely mitigated by the use of compositions containing known antimicrobial actives, there is a need to improve the effectiveness of these actives while still providing the use of active agents.

- 1 039964 active components obtained from natural sources. The present inventors have found that synergistic antifungal as well as antibacterial efficacy can be achieved when certain antimicrobial lipids (PML) are combined with selected essential oil actives. Antimicrobial lipids that have been found to be particularly useful in the present invention are sapienic acid, palmitoleic acid, sphingosine, dihydrosphingosine, 6-hydroxysphingosine, and phytosphingosine. Essential oil actives found to be effective in combination with the above PML are terpineol or thymol.

CN 104800123 A (Walch Guangzhou Commodity Co Ltd, 2015) discloses a soap-based antibacterial shower gel and a method for preparing the same. The shower gel includes the following ingredients: thymol, salicylic acid, plant extracts, ethyl alcohol, propylene glycol, erythritol, lauric acid, myristic acid, palmitic acid, potassium hydroxide, glycol distearate, sodium dihexyl sulfosuccinate, cocamidopropyl betaine, sodium cocoyl glycinate, polyquaternium-7, complex polyglyceric fatty acid ester, ethylenediaminetetraacetic acid, tetrasodium salt, sodium chloride, citric acid, essence, preservative and water. Soap-based antibacterial shower gel is mild and skin-friendly, can effectively resist bacteria and moisturize the skin, and is especially suitable for people with thicker cuticles, high oil secretion and skin itching.

WO 13030360 A2 (Unilever) discloses liquid personal care compositions containing di or tricarboxylic acid or salts thereof in combination with thymol or terpineol. The combination provides a fast acting synergistic antimicrobial effect.

WO 13083393 A1 (Unilever) discloses a method for disinfecting a surface and an antibacterial composition that achieves this. The compositions include selected antibacterial actives, specific polymers and selected hydrotropes.

To the best of our knowledge, the PML claimed in the present invention in combination with selected essential oil actives have not been disclosed for synergistic antimicrobial activity.

Thus, it is an object of the present invention to provide a personal care composition that exhibits synergistic antimicrobial activity compared to the individual components.

Statement of the Invention

According to a first aspect of the present invention, an antimicrobial composition is provided comprising:

(i) from 0.01 to 5% by weight of an essential oil active selected from thymol or terpineol;

(ii) 0.01 to 5% by weight of an antimicrobial lipid selected from sapienic acid, palmitoleic acid, sphingosine, dihydrosphingosine, phytosphingosine, and 6-hydroxysphingosine; and (iii) a cosmetically acceptable carrier.

The second aspect of the present invention relates to a non-therapeutic method for providing antimicrobial efficacy to a body surface of an individual, comprising the step of applying the composition of the first aspect to the desired surface.

In accordance with yet another aspect, a therapeutic method for providing antimicrobial efficacy to a body surface of an individual is disclosed, comprising the step of applying the composition of the first aspect to a desired (desired) surface.

In accordance with another aspect, an antimicrobial composition is disclosed, comprising:

(i) from 0.01 to 5% by weight of an essential oil active selected from thymol or terpineol;

(ii) 0.01 to 5% by weight of an antimicrobial lipid selected from sapienic acid, palmitoleic acid, sphingosine, dihydrosphingosine, phytosphingosine, and 6-hydroxysphingosine; and (iii) a cosmetically acceptable carrier for use in the treatment of acne or dandruff.

Detailed description of the invention

These and other aspects, features and advantages will become apparent to those skilled in the art from a reading of the following detailed description and the appended claims. For the avoidance of ambiguity, any feature of one aspect of the present invention may be used in any other aspect of the invention. The word containing is intended to mean including, but not necessarily consisting of or composed of. In other words, the steps or options listed are not meant to be exhaustive. It should be noted that the examples given in the description below are intended to illustrate the invention and are not intended to limit the invention to these examples as such. Likewise, all percentages are by weight unless otherwise noted. Except for working and comparative examples, or where expressly stated otherwise, all numbers in this specification and claims indicating amounts of material or use

- 2 039964 reaction conditions, physical properties of materials and/or use, should be understood as modified by the word approximately. Numeric ranges expressed in x to y format are understood to include x and y. When multiple preferred ranges are described in x to y format for a particular feature, it is understood that all ranges spanning different endpoints are also considered. In other words, when specifying any ranges of values, any particular upper value can be associated with any specific lower value.

The disclosure contained herein is to be considered as covering all embodiments that have multiple dependencies, regardless of the fact that claims may not have multiple dependencies.

Where a feature is disclosed in relation to a particular aspect of the invention (eg, a composition of the invention), such disclosure should also be considered applicable to any other aspect of the invention (eg, a method of the invention), mutatis mutandis.

Under the antimicrobial composition in the context of the present description means that it includes a composition for topical application to the skin, hair and/or scalp of mammals, especially humans. Such a composition is usually applied to the desired local surface of the body for a period of from a few seconds to 24 hours. When the application time, for example, is from a few seconds to several minutes, after which the composition is washed off with water or wiped off, such a composition is called a removable composition or a rinse-off composition. When the composition is applied for a longer period, say, from several minutes to 24 hours, and washed off, usually during normal personal hygiene, such a composition is referred to as a no-rinse composition.

The composition according to the present invention may be rinse-off or no-rinse. Of these two types, it is preferably of the flush type. It includes any product that is applied to the human body to improve appearance, cleanse, control odor, or general aesthetics. The composition of the present invention may be in the form of a liquid, lotion, cream, foam, scrub, gel, bar of soap, shampoo, conditioner, hand wash, face or body wash. More preferably, it is used to prevent or alleviate the symptoms of dandruff on the scalp and/or hair, to protect against acne, or to disinfect the hands or other parts of the human body.

More specifically, the present invention relates to an antimicrobial cleansing composition.

Antimicrobial lipids that, when combined with essential oil actives that provide synergistic antimicrobial activity, include sapienic acid, sphingosine, dihydrosphingosine, palmitoleic acid, phytosphingosine, 6-hydroxysphingosine, or combinations of one or more PML. More preferred PML are sapienic acid, phytosphingosine and dihydrosphingosine, most preferred are phytosphingosine and dihydrosphingosine.

Sapienic acid and palmitoleic acid are usually added to antimicrobial agents in purified form. These fatty acids may be chemically synthesized or derived from a natural source and may be in free fatty acid form or in esterified form, preferably in free form. Natural substances that contain these fatty acids and their derivatives can be obtained from animal or plant sources, including, but not limited to, plant seed extract, fish oil, animal fat, and microbial enzymes. In particular, sapienic acid has been reported to be a major component of Thunbergia alata (winged Thunbergia) seed oil (85% by weight as triglyceride). Purified sapienoic acid or a seed extract containing sapienoic acid may be added to the antimicrobial composition, provided that sapienoic acid is present in the required concentration in the composition of the present invention.

Sphingosine, phytosphingosine, dihydrosphingosine and 6-hydroxyphingosine are sphingoid bases present on human skin. They can be synthesized chemically or obtained by a suitable biotechnological process that results in the formation of sphingoid bases by yeast from materials such as sugar. Sphingoid bases can be added to the antimicrobial composition in purified form. Alternatively, a fermentation broth consisting of large amounts of sphingoid bases can be used, provided that the sphingoid bases are present in the required concentration in the composition of the present invention. PML is from 0.01 to 5%, preferably from 0.1 to 2% by weight of the composition.

Essential oil actives that are effective in combination with PML in the present invention are thymol or terpineol.

Thymol may be added to the antimicrobial composition in purified form. Alternatively, thyme oil or thyme extract containing thymol may be added to the antimicrobial composition, provided thymol is present in the required concentration in the composition of the present invention. Thyme oil or thyme extract is obtained from the thyme plant. The thyme plant is a plant belonging to the genus Thymus and includes the following species: Thymus vulgaris,

- 3 039964

Thymus zygis, Thymus satureoides, Thymus mastichina, Thymus fragssonetti, Thymus maroccanus, Thymus pallidus, Thymus algeriensis, Thymus serpyll, Thymus serpyll, and Thymus citriodorus, but not limited to.

Terpineol is preferably selected from alpha-terpineol, beta-terpineol, gamma-terpineol or mixtures thereof. Particularly preferably, the terpineol is alpha-terpineol. Terpineol may be added to the antimicrobial composition in purified form. Alternatively, pine oil containing terpineol may be added to the antimicrobial composition.

The antimicrobial composition contains 0.01 to 5% of the essential oil active ingredients listed above, preferably 0.05 to 2.0%, more preferably 0.1 to 1.0% by weight of the composition of the present invention.

According to a particularly preferred aspect of the invention, the composition contains a mixture of thymol and terpineol. In this preferred aspect, thymol is present in an amount of 0.01 to 2%, preferably 0.05 to 1%, and terpineol in an amount of 0.01 to 5%, preferably 0.1 to 2% by weight of the composition.

Preferably, the weight ratio of essential oil active to antimicrobial lipid is in the range of 1:1 to 3000:1 at the cellular level, so that the antimicrobial action is most effective.

Evonik Industries is the main supplier of PML, including sphingosine, phytosphingosine, cholesterol and fatty acids.

Without wishing to be bound by any theory, the inventors believe that the synergistic antimicrobial efficacy of essential oil active ingredients in combination with PML is to destroy the microbial membrane.

Preferably, the present invention is substantially free of antimicrobial alcohols (low molecular weight alcohols having one to 7 carbon atoms). By substantially absent is meant that the alcohol concentration is less than the amount required for antimicrobial therapeutic activity. Preferably, the antimicrobial alcohol is present in an amount of less than 1%, more preferably less than 0.1%, and most preferably absent according to the invention.

The composition of the invention contains a cosmetically acceptable carrier. In one aspect, the cosmetically acceptable carrier comprises water. According to another preferred aspect, the carrier further comprises a surfactant. The cosmetically acceptable carrier is such that the composition may be formulated as a cream, lotion, gel, powder, ointment, body wash, hand or face wash, shampoo, hair conditioner or soap, preferably as a shampoo, conditioner, body wash, hand wash or face wash.

Skin care

The composition according to the invention can be used for skin care. The cosmetically acceptable base in such cases may be a liquid or solid material. Generally, the base is present in an amount of from 10% to 99.9%, more preferably from 20% to 95%, most preferably from 40% to 85% of the total weight of the composition, including all available ranges. Particularly preferably, the cosmetically acceptable carrier comprises water. Water is preferably included in an amount of 30 to 90%, more preferably 30 to 85%, most preferably 30 to 80% of the total weight of the sunscreen composition. In addition to water, suitable carrier classes include silicones, polyhydric alcohols, hydrocarbons, triglycerides, and thickening powders.

The skin care composition of the invention may be in any form, including toners, lotions, creams, mousses, scrubs, serums or gels, which are suitable for topical application to the skin. The composition can either be a leave-on product such as skin lotions, creams, antiperspirants, deodorants, lipsticks, foundations, mascaras, sunscreens and sunscreen lotions, or a rinse-off product such as shower gels and toiletries. soap. Preferably the composition is a skin lotion or cream.

The composition may contain an emollient oil which acts as a co-solvent. Suitable emollient oils include, for example, an alkoxylated aromatic alcohol fatty carboxylic acid ester, fatty carboxylic acid esters of polyglycols or diols such as caprylic/capric triglyceride, a fatty alcohol fatty acid ester, an alkoxylated benzyl alcohol derivative, and mixtures thereof. Preferably the emollient oil is caprylic/capric triglyceride.

Typically, such compositions contain a co-solvent in an amount of from 0.01% to 10%, more preferably from 0.1% to 8%, most preferably from 1% to 6%, based on the total weight of the sunscreen composition, including all subranges included in these ranges.

The composition may further comprise sunscreens such as inorganic sunscreens. For example, zinc oxide, titanium dioxide, iron oxide, silicon dioxide such as colloidal silicon dioxide. The amount of such sunscreen agents is preferably 0.1 to 5% of the total weight of the sunscreen composition.

- 4 039964

The composition of the invention may contain a UV-A sunscreen selected from the group consisting of a dibenzoylmethane derivative, a triazine derivative, a benzophenone derivative, and mixtures thereof. In a preferred embodiment, the UV-A sunscreen comprises or is a dibenzoylmethane derivative, eg butylmethoxydibenzoylmethane (sold under the trade name Parsol 1789).

Typically, the sunscreen composition of the present invention contains from 0.1 to 15 wt.% UV-A sunscreen, more preferably from 0.1 to 10%, most preferably from 1 to 5% based on the total weight of the composition and including all subranges related to them.

The composition of the invention may also contain a UV-B sunscreen. A suitable UV-B sunscreen agent of the invention is selected from the group consisting of benzophenone, anthranilate, salicylate, cinnamate, camphor, benzylidenemalonate, triazone, and derivatives thereof. In a preferred embodiment, the UV-B sunscreen comprises or is a cinnamate derivative, such as ethylhexylmethoxycinnamate (sold under the trade name Parsol MCX).

Typically, the composition contains from 0.1 to 20 wt.% UV-B sunscreen agent, more preferably from 0.5 to 18%, most preferably from 1 to 15% based on the total weight of the composition and including all subranges related to him.

A skin lightening agent may also be included in the composition of the invention. The most preferred skin lightening agent is a vitamin B3 compound. The vitamin B3 compound may be niacin, nicotinic acid or niacinamide, preferably niacinamide.

Niacinamide is known to be involved in the secretion of AMP from keratinocytes. The AMP secreted in this way provides an improvement in the immunity of the external surface of the body, for example, on the scalp. Thus, when using niacinamide in the composition of the invention, it is expected that the effectiveness against dandruff will be increased not only by the antifungal activity of the composition of the invention, but also by increasing the scalp's own defense against microbes, due to the use of niacinamide. It is expected that this combination may provide additional long-term protection, for example up to 24 hours of microbial protection.

Niacinamide is preferably present in an amount of 0.01 to 5%, more preferably 0.1 to 3% by weight of the composition. Suitable skin whitening agents other than vitamin B3 and its derivatives are kojic acid, arbutin, tranexamic acid, placenta extract, ascorbic acid and its derivatives (e.g. magnesium ascorbyl phosphate, sodium ascorbyl phosphate, ascorbyl glucoside and ascorbyl tetraisopalmitates), aloe extract, ammonium lactate, azelaic acid. acid, citrate esters, ellagic acid, glycolic acid, green tea extract, hydroquinone, lemon extract, linoleic acid, vitamins such as vitamin B6, vitamin B12, vitamin C, vitamin A, dicarboxylic acid, resorcinol derivatives, hydroxycarboxylic acid, such as lactic acid and its salts (eg sodium lactate), or a mixture thereof. Typically, the skin whitening agent is present in an amount of 0.1 to 10%, more preferably 0.2 to 5%, most preferably 0.3 to 3% of the total weight of the composition, including all ranges thereof.

The skin care compositions may also contain other ingredients that are conventional in the art for improving physical properties and performance. Suitable ingredients include humectants, thickeners, opacifiers, binders, dyes and pigments, pH adjusters, preservatives, optics, fragrances, viscosity modifiers, biological additives, buffering agents, conditioners, natural extracts, essential oils, and skin benefits, including anti-inflammatory agents. agents, cooling agents, antiperspirants, anti-aging agents, anti-acne agents, antimicrobial agents, and antioxidants, but are not limited to.

Skin cleansing

The composition according to the invention can be used for skin care, for example, for washing the body or face. The antimicrobial composition may further comprise a surfactant. Preferred surfactants are non-ionic surfactants such as C ₈ -C ₂₂ , preferably C8-C16 fatty alcohol ethoxylates containing from 1 to 8 ethylene oxide groups when the product is in liquid form. Surfactants are preferably selected from primary alkyl sulfate, secondary alkyl sulfonates, alkyl benzene sulfonates or ethoxylated alkyl sulfates. The composition may further comprise an anionic surfactant such as an alkyl ether sulfate, preferably having 1 to 3 ethylene oxide groups, either from a natural or synthetic source, and/or sulfonic acid. Particularly preferred are sodium lauryl ether sulfates. Alkyl polyglucosides may also be present in the composition, preferably having a carbon chain length of C6 to C16.

Thus, in a particularly preferred aspect, the antimicrobial compositions comprise a surfactant selected from the group of anionic surfactants, fatty acid amide, alkyl sulfate, linear alkyl benzene sulfonate, and combinations thereof.

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When surfactants are present, the antimicrobial composition preferably contains 1 to 90% surfactant by weight of the composition.

When a surfactant is used, a particularly preferred surfactant is soap. Soap is a suitable surfactant for the use of the antimicrobial composition of the invention as a personal care product. The soap is preferably a C8-C24 soap, more preferably a _C10 - _C20 soap and most preferably a _C12 - _C18 soap. The soap cation can be an alkali metal, an alkaline earth metal or an ammonium. Preferably, the soap cation is selected from sodium, potassium or ammonium. More preferably, the soap cation is sodium or potassium.

A typical fatty acid blend consists of 5-30% coconut fatty acids and 70-95% fatty acids by weight of soap. Fatty acids derived from other suitable oils/fats such as peanut, soybean, tallow, palm, palm kernel, etc. may also be used in other desired proportions.

When present, the soap of the present invention is preferably present in an amount of 1 to 90%, preferably 10 to 85%, more preferably 25 to 75% by weight of the composition. Preferred compositions may include other known ingredients such as perfumes, pigments, preservatives, emollients, sunscreens, emulsifiers, gelling agents and thickeners. The choice of these ingredients will largely depend on the format of the composition.

Water is the preferred carrier. When water is present, it is preferably present in an amount of at least 1%, more preferably at least 2%, even more preferably at least 5% by weight of the composition. When water is the carrier, the preferred liquid composition contains from 10 to 99.8 wt.% water. The liquid antimicrobial composition is useful as a skin antiseptic, for skin cleansing, in particular for washing hands or washing the face. When water is the carrier, the preferred solid composition contains from 5 to 30% by weight of water.

The solid antimicrobial composition is preferably in the form of a molded solid, more preferably in the form of a bar. The solid antimicrobial composition is particularly useful for cleansing the skin, in particular for washing hands or washing the face.

According to another aspect, the inorganic particulate material is also a suitable carrier. When the inorganic particulate material is the carrier, the antimicrobial composition is in solid form. Preferably the inorganic particulate material is talc. When the inorganic particulate material is talc, the solid antimicrobial composition is particularly useful as talc powder for application to the face or body.

In another aspect of the present invention, the composition of the present invention is suitable for use in personal care wipes.

Shampoo

According to a particularly preferred aspect of the invention, the composition is a shampoo. The composition of the invention, especially shampoos, contains an anionic surfactant, for example an alkyl sulfate and/or ethoxylated alkyl sulfate surfactant. These anionic surfactants are preferably present in an amount of 1 to 20%, preferably 2 to 16%, more preferably 3 to 16% by weight of the composition. Preferred alkyl sulfates are C ₈ . ₁₈ alkyl sulfates, more preferably C ₁₂ -C ₁₈ alkyl sulfates, preferably in the form of a salt with a solubilizing cation such as sodium, potassium, ammonium or substituted ammonium.

Preferred alkyl ether sulfates are those having the formula: RO(CH ₂ CH ₂ O) _n SO ₃ M; where R is alkyl or alkenyl having 8 to 18 (preferably 12 to 18) carbon atoms; n is a number having an average value greater than at least 0.5, preferably from 1 to 3, more preferably from 2 to 3; and M is a solubilizing cation such as sodium, potassium, ammonium or substituted ammonium. An example is sodium lauryl ether sulfate (SLES). Particularly preferred is SLES having an average degree of ethoxylation from 0.5 to 3, preferably from 1 to 3.

Shampoo compositions of the invention may contain one or more additional anionic cleansing surfactants that are cosmetically acceptable and suitable for topical application to the hair.

Examples of other suitable anionic cleansing surfactants are alkaryl sulfonates, alkyl succinates, alkyl sulfosuccinates, alkyl ether sulfosuccinates, N-alkyl sarcosinates, alkyl phosphates, alkyl ether phosphates and alkyl ether carboxylic acids and their salts, especially their sodium, magnesium, ammonium and mono-, di- and triethanolamine salts. Alkyl and acyl groups usually contain from 8 to 18, preferably from 10 to 16 carbon atoms, and may be unsaturated. The alkyl ether sulfosuccinates, alkyl ether phosphates and alkyl ether carboxylic acids and their salts may contain from 1 to 20 ethylene oxide or propylene oxide units per molecule.

Typical anionic cleansing surfactants for use in the compositions of the invention include sodium oleyl succinate, ammonium lauryl sulfosuccinate, sodium lauryl ether sulfosuccinate, sodium dodecylbenzenesulfonate,

- 6 039964 triethanolamine indodecylbenzenesulfonate, lauryl ether carboxylic acid and sodium N lauryl sarcosinate.

Suitable additional anionic cleansing surfactants are sodium lauryl ether sulfosuccinate(n) EO (where n is from 1 to 3), lauryl ether carboxylic acid(n) EO (where n is from 10 to 20).

Mixtures of any of the above anionic cleansing surfactants may also be suitable.

The composition according to the invention preferably additionally contains an amphoteric surfactant, preferably a betaine surfactant, preferably an alkylamidopropyl betaine surfactant, for example cocamidopropyl betaine. In a preferred embodiment, the composition contains from 0.1 to 10 wt.%, preferably from 0.5 to 8 wt.%, more preferably from 1 to 5 wt.% betaine surfactant.

To improve the deposition of active substances from the compositions according to the invention, especially shampoos, they usually include cationic polymers. In the present invention, it is also preferred that the composition further comprises from 0.01 to 2.0% of the cationic polymer. The cationic polymer is preferably guar hydroxypropyltrimonium chloride. The guar polymer predominantly contains galactomannan polymer chains. This polymer is available in various molecular weights and degrees of cationic substitution depending on how much guar has been hydrolyzed and cationized. The cationic polymer is preferably present in an amount of 0.04 to 0.5%, more preferably 0.08 to 0.25% by weight of the composition.

The pH value of the shampoo composition according to the invention is preferably equal to or greater than 4.0, more preferably in the range from 5.0 to 7.0.

The composition according to the invention, especially for anti-dandruff shampoos, preferably additionally contains one or more anti-dandruff agents. Preferred agents are selected from zinc pyrithione, azole compounds (eg climbazole or ketoconazole), octopirox, selenium sulfide or combinations thereof. According to the present invention, it is necessary to include zinc pyrithione as an anti-dandruff agent.

Zinc pyrithione (ZPTO) is short for 1-hydroxy-2-pyridinethione zinc. The polyvalent metal salt of pyrithione is represented by the following general formula:

In the case of zinc pyrithione, the metal cation M is zinc.

The zinc pyrithione is preferably present in an amount of 0.1 to 3.0%, more preferably 0.1 to 2.0% by weight of the composition. ZPTO is a particulate material. While the particle size is not critical to achieving the benefits of the present invention, the ZPTO particle size is preferably 0.25 to 8 µm, more preferably 0.5 to 8.0 µm, and even more preferably 1.0 to 7.5 µm. ZPTO is commercially available from Kolon Life Science Inc., Sino Lion (USA) Ltd, Lonza and other vendors. The presence of an additional zinc compound in the composition is believed to improve the effectiveness of the pyrithione metal salt against dandruff. Suitable zinc compounds are zinc oxide, zinc citrate, zinc malonate, zinc carbonate, or combinations thereof. The zinc compound is preferably present in an amount of 0.1 to 3%, more preferably 0.1 to 1.5% by weight of the composition.

The shampoo composition of the invention preferably further comprises a conazole fungicide. Preferably the conazole fungicide is selected from ketoconazole, climbazole or mixtures thereof. The azole fungicide is preferably present in an amount of 0.01 to 2%, more preferably 0.025 to 0.75% by weight of the composition. The presence of the conazole fungicide is believed to improve the deposition of zinc pyrithione.

The composition preferably further comprises a vitamin B3 compound. A preferred B3 vitamin compound is niacinamide.

The niacinamide is preferably present in an amount of 0.1 to 5%, more preferably 0.5 to 5%, even more preferably 0.5 to 3% and most preferably 1.0 to 3.0% by weight of the composition.

suspending agent

Preferably, the composition of the invention further comprises a suspending agent. Suitable suspending agents are selected from polyacrylic acids, cross-linked polymers of acrylic acid, copolymers of acrylic acid with a hydrophobic monomer, copolymers of carboxylic acid-containing monomers and acrylic acid esters, cross-linked copolymers of acrylic acid and acrylate esters, heteropolysaccharide gums, and crystalline long chain acyl derivatives. The long chain acyl derivative is preferably selected from ethylene glycol stearate, fatty acid alkanolamides having from 16 to 22 carbon atoms, and mixtures thereof. Ethylene glycol distearate and polyethylene glycol 3-distearate are the preferred lengths

- 7 039964 no-chain acyl derivatives, since they impart a pearlescent effect to the composition. Polyacrylic acid is commercially available as Carbopol 420, Carbopol 488, or Carbopol 493. Acrylic acid polymers crosslinked with a polyfunctional agent may also be used; they are commercially available as Carbopol 910, Carbopol 934, Carbopol 941 and Carbopol 980. An example of a suitable carboxylic acid copolymer containing monomer and acrylic acid esters is Carbopol 1342. All Carbopol (trademark) materials are available from Goodrich.

Suitable crosslinked polymers of acrylic acid and acrylate esters are Pemulen TR1 or Pemulen TR2. A suitable heteropolysaccharide gum is xanthan gum, eg available as Kelzan®.

Mixtures of any of the above suspending agents may be used. A mixture of a crosslinked acrylic acid polymer and a crystalline long chain acyl derivative is preferred.

The suspending agent, if included, is usually present in the shampoo composition of the invention in an amount of 0.1 to 10%, preferably 0.5 to 6%, more preferably 0.5 to 4% of the total weight of the suspending agent, based on the total weight of the composition.

The composition of the invention may contain other ingredients to improve efficacy and/or consumer acceptance. Such ingredients include fragrances, colorants and pigments, pH adjusters, pearlescent agents or opacifiers, viscosity modifiers, preservatives, and natural hair nutrients such as botanicals, fruit extracts, sugar derivatives, and amino acids.

The composition of the invention is preferably an aqueous composition. It preferably contains a large amount of water, preferably from 70 to 95% by weight of the composition.

Hair conditioner

When conditioning benefits are to be provided by a composition of the invention, the composition is referred to as a hair conditioner. Generally, the most popular conditioning agents used in hair care compositions are water-insoluble oily materials such as mineral oils, natural oils such as triglycerides and silicone polymers. The beneficial effect of conditioning is achieved by the fact that the oily material is deposited on the hair, resulting in the formation of a film that makes the hair easier to comb when wet and makes it more manageable when dry. A particularly useful conditioning agent is a silicone compound, preferably a non-volatile silicone compound. Advantageously, the compositions herein may include one or more silicones. Silicones are conditioning agents in particulate or suspended particulate form. They are designed to be applied to the hair, remaining after washing the hair with water. Suitable silicone oils may include polyalkylsiloxanes, polyarylsiloxanes, polyalkylarylsiloxanes, polyethersiloxane copolymers, and mixtures thereof. Amino silicones are often included in shampoo formulations. Amino silicones are silicones containing at least one primary amino group, a secondary amino group, a tertiary amino group, or a quaternary ammonium group. High molecular weight silicone gums can also be used. Another useful type are crosslinked silicone elastomers such as Dimethicone/Vinyl/Dimethicone Crosspolymers (eg Dow Corning 9040 and 9041).

The amount of silicone in the compositions where they are present may be from about 0.1 to 10 wt.%, preferably from about 0.1 to 8 wt.%, more preferably from about 0.3 to 5 wt.% by weight of the compositions for hair care.

The pH value of the conditioning composition according to the invention is preferably equal to or greater than 4.0, more preferably in the range from 5.0 to 7.0.

The hair conditioning composition typically contains conditioning surfactants selected from cationic surfactants, used alone or in admixture. Подходящие катионные сурфактанты для использования в кондиционирующих композициях по настоящему изобретению включают цетилтриметиламмония хлорид, бегенилтриметиламмония хлорид, цетилпиридиния хлорида, тетраметиламмония хлорид, тетраэтиламмония хлорид, октилтриметиламмония хлорид, додецилтриметиламмония хлорид, гексадецилтриметиламмония хлорид, октилдиметилбензиламмония хлорид, децилдиметилбензиламмония хлорид, стеарилдиметилбензиламмония хлорид, дидодецилдиметиламмония хлорид, диоктадецилдиметиламмония хлорид , tallowtrimethylammonium chloride, dihydrogenated tallowdimethylammonium chloride (eg Arquad 2HT/75 from Akzo Nobel), cocotrimethylammonium chloride, PEG-2-oleammonium chloride and their respective hydroxides. Other suitable cationic surfactants include CTFA designations Quaternium-5, Quaternium-31 and Quaternium-18. Mixtures of any of the above materials may also be suitable. A particularly useful cationic surfactant for use in the conditioners of the invention is cetyltrimethylammo.

- 8 039964 nium chloride, commercially available, for example, as GENAMIN STAC from Hoechst Celanese. Another particularly useful cationic surfactant for use in the air conditioners of the invention is behenyltrimethylammonium chloride, commercially available, for example, as GENAMIN KDMP from Clariant. Another preferred cationic surfactant is stearamidopropyldimethylamine.

The most preferred cationic surfactants for use in the composition are stearamidopropyldimethylamine, behentrimonium chloride or stearyltrimethylammonium chloride. In conditioners according to the invention, the level of cationic surfactant is usually from 0.1 to 5%, preferably from 0.5 to 2.5% by weight of the composition.

The hair conditioning compositions of the invention may preferably also additionally contain a fatty alcohol. The combined use of fatty alcohols and cationic surfactants in conditioning compositions is believed to be particularly advantageous because it results in the formation of a lamellar phase in which the cationic surfactant is dispersed.

Typical fatty alcohols contain from 8 to 22 carbon atoms, more preferably from 16 to 22. Fatty alcohols are usually compounds containing straight chain alkyl groups. Examples of suitable fatty alcohols include cetyl alcohol, stearyl alcohol, and mixtures thereof. The use of these materials is also advantageous in that they contribute to the overall conditioning properties of the compositions of the invention.

The level of fatty alcohol in conditioners of the invention is typically 0.5 to 10%, preferably 0.1 to 8%, more preferably 0.2 to 7%, most preferably 0.3 to 6% by weight of the composition. The weight ratio of cationic surfactant to fatty alcohol is 1:1 to 1:10, more preferably 1:1.5 to 1:8, most preferably 1:2 to 1:5.

The invention also relates to a method for providing antimicrobial efficacy to a body surface of an individual, comprising the step of applying the composition of the invention to the desired surface.

The method can be used to prevent or treat acne, dandruff, or to maintain general hygiene.

The present invention also relates to a method for inhibiting the growth of bacteria or fungi on a body surface. This method is particularly effective against fungi such as Malassezia furfur and bacteria such as P. acnes. The method includes the step of applying the composition of the first aspect to the scalp or any other body surface of the individual. Alternatively and preferably, the above step is followed by rinsing the surface with water. The rinsing step is typically carried out for 1 to 5 minutes after application of the composition to the skin or hair/scalp. In one aspect, the invention provides non-therapeutic benefits.

The invention will now be illustrated with reference to the following non-limiting examples.

Examples

Examples 1-8.

The synergistic interaction between active essential oil and PML compounds was determined using the ZFIC assay against P. acnes. A brief description of the method is given below.

Methods: ZFIC assay against P. acnes.

Preparation of microorganisms: P. acnes (ATCC 6919) was inoculated onto a plate with enhanced clostridial agar medium (RCMA, solution A) and cultured under anaerobic conditions in an anaerobic jar at 37°C for 72-96 h. A single colony was cultured in enhanced clostridial medium ( RCM solution B) and incubated anaerobically at 37° C. for 72-96 hours. The final cell density was adjusted to approximately 5x10 ⁷ cells/ml by dilution using RCM. The inoculum was then further diluted 1:1000 in Luria-Bertani medium (LB, solution C) to give about 5 x 10 ⁴ cells/ml.

Solution A. Reinforced clostridial agar medium (RCMA):

d - RCM (HopeBio), d - Agar (Oxoid), deionized water up to 1000 ml, autoclave.

Solution B. Enhanced clostridial medium (RCM):

g RCM(HopeBio), deionized water up to 1000 ml, autoclave.

Solution C. Luria-Bertani Medium (LB):

g tryptone (Oxoid), g sodium chloride (SCR), g yeast extract (Oxoid), deionized water up to 1000 ml, autoclave.

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In vitro sensitivity analysis

The active essential oil was serially diluted (2-fold) to prepare samples in the range of 10 to 10,000 ppm in LB growth medium. The PML compound was serially diluted (2-fold) to prepare in the range of 15.6 to 1000 ppm for sapienoic acid and palmitoleic acid; and 2-125 ppm for other PML in LB growth medium.

Binary combinations of essential oil and PML compound were prepared in a 96-well plate by mixing 20 µl of essential oil solution with 20 µl of PML compound. The solution in each well was further mixed with 160 μl of P. acnes in LB. The final cell density in the assay plate was about 4x10 ⁴ cells/ml and the final concentration of active substances in each well of the 96-well plate is shown below.

Active concentrations of essential oils (in ppm): 1000; 500; 250; 125; 62.5; 31.3; 15.6; 7.8; 3.9; 2.0; 1.0 and 0.

Concentrations of fatty acid PML compound of sapienic acid and palmitoleic acid (ppm): 100; 50; 25; 12.5; 6.25; 3.13; 1.56 and 0. Sphingosine PML compound concentrations (ppm): 12.5; 6.3; 3.1; 1.6; 0.8; 0.4; 0.2 and 0.

The tablet was incubated anaerobically at 37°C for 50 hours. Then, 20 µl of Alamar Blue (0.01%) was added to each well, followed by aerobic incubation for two to three days to observe the color change. The red color indicated microbial growth, while the unchanging blue color indicated no growth. In addition, it was also confirmed that the test compound itself did not cause an Alamar Blue discoloration with a control mixture without the addition of microbes.

Calculations

Minimum Inhibition Concentration (MIC).

The MIC is defined as the absolute lowest concentration of an active substance that provides complete inhibition of microbial growth, as shown by Alamar Blue under assay conditions.

The MIC values of sapienoic acid, palmitoleic acid, sphingosine, phytosphingosine, and dihydrosphingosine were determined to be 1 to 4 ppm, 1 ppm, 0.4 ppm, 0.2 ppm, and 0.2 ppm, respectively. The MIC of thymol is 62.5 ppm and that of terpineol is 1000 ppm.

Fractional inhibitory concentration (FIC).

The different behavior of inhibitory antimicrobials alone and in mixtures has been extensively studied using the concepts of fractional concentration (FC) and fractional inhibitory concentration (FIC). The parameter can be defined like this:

FIC (component a) = MIC (component a tested as a mixture) / MIC (component tested as a single active compound).

Synergy and Additivity

Interactions between antimicrobials can be additive, synergistic, or antagonistic, depending on whether the efficacy of the combination is equivalent to, greater than, or less than that obtained for the same total concentration of the individual components when tested separately.

These ratios can be expressed mathematically by summing the fractional MIC values for all components present in the mixture to obtain the fractional inhibition index. There is no consensus in the academic or patent literature to define the precise ZFIC limit values that distinguish synergism from additivity or antagonism. In this study, we adopted a liberal approach defining any binary mixture with a ZFIC <0.9 as evidence of synergistic behavior.

ZFIC = FIC (component 1) + FIC (component 2)

ZFIC = 1 corresponds to additive antimicrobial activity

ZFIC > 1 corresponds to antagonistic antimicrobial activity

ZFIC <0.9 consistent with synergistic antimicrobial activity

results

Based on the concentration range of essential oil actives (0 to 1000 ppm) and PML compound (0 to 100 ppm) in which experiments were performed, the ZFIC value of the combinations is shown in the table below.

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Example Combination EFIC 1 Thymol + sapienoic acid 0.52 2 thymol + sphingosine 0.50 3 thymol + dihydrosphingosine 0.50 4 thymol + phytosphingosine 0.50 5 thymol + palmitoleic acid 0.51 6 Terpineol + Sapienic Acid 0.56 7 Terpineol + sphingosine 0.75 8 Terpineol + dihydrosphingosine 0.50 9 Terpineol + phytosphingosine 0.56 10 Terpineol + palmitoleic acid 0.625

The data in the table above indicate that each of the antimicrobial lipids of the present invention, when combined with essential oil actives such as thymol and terpineol, exhibits synergistic antimicrobial activity.

The experiments described above were performed in an in vitro assay to evaluate synergistic antimicrobial behavior. It is expected that the concentrations that will be used to prepare the composition for topical application will be very different. Concentrations can be several orders of magnitude higher for the following reasons, which affect the difference in concentrations in volume compared to the concentration at the cellular level. The composition can be formulated as an emulsion or gel with a very large number of additional ingredients which affect the concentration of the active substances needed in the oil phase and in the aqueous phase, which can be very different. They can also have very different physical and hydrodynamic properties, such as distribution coefficients, diffusion rates, convective transport rates, and rheological properties. Therefore, it is expected that the concentrations that will be used when formulated as a composition will be different from the concentrations at the cellular level at which the experiments were carried out, usually several orders of magnitude higher.

Claims (8)

CLAIM 1. Antimicrobial composition containing: (i) from 0.01 to 5% by weight of an essential oil active selected from thymol, terpineol or mixtures thereof; (i) 0.01 to 5% by weight of an antimicrobial lipid selected from sapienic acid, palmitoleic acid, sphingosine, dihydrosphingosine, phytosphingosine, and 6-hydroxysphingosine; and (iii) a cosmetically acceptable carrier. 2. The composition of claim 1 wherein the antimicrobial lipid is selected from sapienic acid, phytosphingosine and dihydrosphingosine. 3. Composition according to claim 1 or 2 containing thymol and terpineol. 4. The composition according to any of the previous paragraphs, which is a cream, lotion, gel, powder, ointment; body wash, hand wash or face wash; shampoo, hair conditioner or soap. 5. A composition according to any one of the preceding claims, wherein the cosmetically acceptable carrier contains a surfactant. 6. A non-therapeutic method of providing antimicrobial efficacy to a body surface of an individual, comprising the step of applying a composition according to any one of the preceding claims to the desired surface. 7. A non-therapeutic method according to claim 6 for the prevention or treatment of acne, dandruff or for maintaining general hygiene. 8. An antimicrobial composition for treating acne or dandruff, comprising: (i) from 0.01 to 5% by weight of an essential oil active selected from thymol or terpineol; (i) 0.01 to 5% by weight of an antimicrobial lipid selected from sapienic acid, palmitoleic acid, sphingosine, dihydrosphingosine, phytosphingosine, and 6-hydroxysphingosine; and (iii) a cosmetically acceptable carrier.