CN120603601A - Avocado unsaponifiables for use in treating conditions caused by Malassezia yeast - Google Patents

Abstract

The present invention relates to avocado unsaponifiable matter or a composition containing it, for use in preventing and/or treating conditions and diseases caused by Malassezia yeasts, wherein the unsaponifiable matter contains at least 50% by weight of furanic lipids relative to the total mass of the unsaponifiable matter. The present invention also relates to the cosmetic use of avocado unsaponifiable matter or a composition containing it, for preventing and/or treating dandruff, wherein the unsaponifiable matter contains at least 50% by weight of furanic lipids relative to the total mass of the unsaponifiable matter. Furthermore, the present invention relates to a method for preparing avocado unsaponifiable matter.

Description

Avocado unsaponifiables for the treatment of malassezia-induced conditions

Technical Field

The present invention relates to avocado unsaponifiables or compositions comprising avocado unsaponifiables for the prevention and/or treatment of pathologies and diseases caused by yeasts of the genus Malassezia (Malassezia). The invention also relates to the cosmetic use of avocado unsaponifiables or compositions comprising avocado unsaponifiables for the prevention and/or treatment of dandruff. Furthermore, the present invention relates to a method for preparing avocado unsaponifiables.

Background

Human microbiomes comprise a wide variety of microorganisms such as bacteria, viruses and fungi. Malassezia yeasts are part of the Basidiomycetes (Basidiomycetes), part of the human symbiotic flora, in particular in the scalp. The yeast releases hydrolases (e.g., lipases and phospholipases C) so that the yeast host's lipids are capable of producing fatty acids. In seborrheic dermatitis patients, malassezia yeast invades the stratum corneum and free fatty acids produced by the release of lipases are the origin of the inflammatory process. Inflammation results in hyperproliferation of the stratum corneum and incomplete differentiation of keratinocytes, which alters the function of the stratum corneum, in particular its barrier function, leading to easier access by malassezia yeasts. Malassezia yeast is involved in many skin diseases, such as seborrheic dermatitis, malassezia folliculitis, dandruff, pityriasis capitis, or pityriasis versicolor.

Seborrheic dermatitis is a fairly common benign chronic erythema squamous inflammatory skin disease that develops in bursts most commonly affecting the scalp and face, particularly the nasolabial folds and eyebrows. One typical form affects infants, presenting as yellow crusts on the scalp (scab) or face.

Scab is a form of Infant Seborrheic Dermatitis (ISD) with oily scale-borne erythema on the scalp, with the highest incidence in the third month after birth. Factors that cause eschar are diverse. Excessive sebum production may be one of these factors, but is not necessarily responsible for its appearance, which causes dead keratinocytes to adhere to the skin surface and prevent their physiological desquamation. Invasion of the stratum corneum by malassezia yeast as described above is another of these factors.

In the prior art, therapeutic strategies for treating seborrheic dermatitis (including eschar) aim to regulate sebum production, calm skin inflammation and reduce growth of malassezia yeasts. Such treatments include the use of anti-inflammatory agents (e.g., corticosteroids for the skin) and antifungal agents (e.g., ketoconazole, lithium gluconate, or ciclopirox olamine). Treatment may also involve emollients (e.g., mineral or olive oil or petrolatum), as well as exfoliants (e.g., salicylic acid).

In general, the treatment options for conditions and diseases caused by malassezia yeasts, particularly pityriasis versicolor and seborrheic dermatitis, are antifungal and anti-inflammatory treatments. The effect on sebum secretion is generally insufficient to treat conditions and diseases caused by malassezia yeasts.

Furthermore, normal seborrheic secretion does not prevent the onset of abnormal growth cycles in malassezia yeasts. Thus, treatments that act solely on sebum secretion, for example by inhibiting the activity of 5-alpha reductase, cannot be the treatment of choice for these diseases. In addition, sebum secretion is not only controlled by the 5-alpha reductase pathway, but it may be activated by other pathways or other causes (e.g., physical or psychological stress).

The long-term use of corticosteroids may cause side effects such as skin atrophy, streaks, telangiectasia, folliculitis, hypopigmentation and habituation, the long-term use of antifungals may cause side effects such as contact dermatitis, and in addition, other treatments have limitations of use, for example, lithium gluconate is only suitable for treating immunocompetent adults.

Thus, there is a real need for a composition for the prevention and/or treatment of diseases caused by malassezia yeasts, which can be topically applied, does not have the side effects of the corticosteroids and antifungal agents described above, and can be used for children, infants and neonates.

In the context of the present invention, the applicant has surprisingly found that avocado unsaponifiables are capable of inhibiting the growth of malassezia yeasts.

In its international patent application WO 2004/012696, the applicant describes a method for obtaining avocado unsaponifiables enriched in furan lipids. Generally, avocado unsaponifiables are used for the treatment of certain connective tissue diseases (e.g. osteoarthritis), joint conditions (e.g. rheumatism), or periodontal diseases (e.g. gingivitis or periodontitis) (see e.g. international patent application WO 2013/098293).

Thus, the applicant has found that avocado unsaponifiables are useful for the prevention and/or treatment of pathologies and diseases caused by malassezia yeasts, in particular for the prevention and/or treatment of seborrheic dermatitis, in particular of infants (for example, eschar, pityriasis scalp, malassezia folliculitis, pityriasis versicolor and dandruff).

Indeed, avocado unsaponifiables can inhibit the growth of malassezia yeasts and act as anti-inflammatory, soothing and/or antipruritic agents.

Disclosure of Invention

According to a first aspect, the present invention relates to an avocado unsaponifiable for the prevention and/or treatment of pathologies and diseases caused by yeasts of the genus malassezia, said avocado unsaponifiable containing at least 50% by weight, preferably at least 60% by weight, of furan lipids relative to the total mass of the avocado unsaponifiable.

According to a second aspect, the present invention relates to a composition comprising an avocado unsaponifiable containing at least 50% by weight, preferably at least 60% by weight of furan lipids relative to the total mass of the avocado unsaponifiable, for the prevention and/or treatment of pathologies and diseases caused by yeasts of the genus malassezia.

According to a third aspect, the present invention relates to the cosmetic use of an avocado unsaponifiable containing at least 50% by weight, preferably at least 60% by weight, of furan lipids relative to the total mass of the avocado unsaponifiable, for the prevention and/or treatment of dandruff.

According to a fourth aspect, the present invention relates to the cosmetic use of a composition comprising an avocado unsaponifiable containing at least 50% by weight, preferably at least 60% by weight, of furan lipids relative to the total mass of the avocado unsaponifiable, for the prevention and/or treatment of dandruff.

According to a fifth aspect, the present invention relates to a process for the preparation of avocado unsaponifiables, comprising at least the following steps:

i. the heat treatment step of the avocado oil concentrate is advantageously carried out at a temperature of from 60 to 90C, preferably 80C,

A step of saponifying the avocado oil concentrate in the presence of an aqueous alkali or of an aqueous alkali of the sodium hydroxide or potassium hydroxide type to obtain avocado unsaponifiables,

Optionally precipitating the soap obtained in step ii,

At least one step of extracting the product obtained in step ii or iii, wherein the avocado unsaponifiable is purified by liquid/liquid or solid/liquid extraction, at least 50% by volume of a solvent selected from the group consisting of ethyl acetate, propyl acetate and butyl acetate, relative to the total volume of the extraction solvent, and

Optionally additional purification steps of distillation and/or deodorization.

Definition of the definition

For the purposes of the present invention, the term "malassezia yeast" refers to any species and variant of yeast belonging to the genus malassezia (also known as pityrosporum (Pityrosporum)). Examples of yeast species that may be mentioned are, but are not limited to, malassezia furfur (Malassezia furfur), in particular CIP 1634.86 strain, malassezia globosa (Malassezia globosa), malassezia limiter (Malassezia restricta), malassezia axostyle (Malassezia sympodialis), malassezia dulcis (Malassezia obtuse), malassezia schneisser Phil (Malassezia slooffiae), malassezia thickii (Malassezia pachydermatis) and malassezia folliculitis (Malassezia folliculitis).

For the purposes of the present invention, "dandruff" refers to unsightly dead cell clumps present on the scalp.

For the purposes of the present invention, "pityriasis versicolor" refers to a skin infection caused by malassezia furfur, which appears as a plurality of squamous patches of white to brown to pink color.

For the purposes of the present invention, the "Minimum Inhibitory Concentration (MIC)" refers to the minimum concentration of a compound that inhibits the growth of a given microorganism.

"Avocado oil concentrate" or "avocado concentrate" means an avocado oil whose unsaponifiable fraction is advantageously concentrated by molecular distillation or cold crystallization.

For the purposes of the present invention, "malassezia folliculitis" is an inflammatory skin condition which is usually manifested as pruritic follicular papulopustular rash distributed over the upper half of the young person, a condition of fungal etiology resembling acne vulgaris, also known as pityrosporum folliculitis.

In general, unsaponifiables are part of fatty substances which remain insoluble in water after prolonged action of alkaline base and can be extracted with organic solvents. Five major classes of substances exist in the unsaponifiable matter of most vegetable oils, saturated or unsaturated hydrocarbons, aliphatic or terpene alcohols, sterols (or "phytosterols"), tocopherols and tocotrienols, carotenoids and lutein.

According to the invention, avocado furan lipids refer to furans monosubstituted in position 2 by a straight C ₁₁-C₁₉ (preferably C ₁₃-C₁₇) hydrocarbon chain, either saturated or containing one or more olefinically or acetylenically unsaturated chains.

The avocado unsaponifiables of the present invention comprise at least one fraction rich in furan lipids (fraction H) and one fraction rich in polyhydroxy fatty alcohols (fraction I). Part H appears first on gas chromatography of avocado oil unsaponifiables.

Part H is:

in thin-layer chromatography, with a front position with Rf of 0.9,

First eluted in a silica gel high pressure liquid chromatograph,

Mainly in gas chromatography.

The term "enriched" means that the content of the above-mentioned different components is respectively higher than the average content of the corresponding components in all vegetable oils well known to the person skilled in the art.

Detailed Description

A first object of the present invention relates to an avocado unsaponifiable matter containing at least 50% by weight, preferably at least 60% by weight of furan lipids relative to the total mass of the avocado unsaponifiable matter, for the prevention and/or treatment of pathologies and diseases caused by yeasts of the genus malassezia.

A second object of the present invention relates to a composition comprising an avocado unsaponifiable containing at least 50% by weight, preferably at least 60% by weight of furan lipids relative to the total mass of the avocado unsaponifiable, for the prevention and/or treatment of pathologies and diseases caused by yeasts of the genus malassezia.

According to a preferred embodiment of the invention, the pathologies and diseases caused by yeasts of the genus malassezia are selected from the group comprising seborrheic dermatitis, in particular infant seborrheic dermatitis (for example scab, pityriasis scalp, malassezia folliculitis and pityriasis versicolor). Preferably, the conditions and diseases caused by malassezia yeasts are selected from the group consisting of seborrheic dermatitis, in particular infant seborrheic dermatitis (e.g. eschar).

The conditions and diseases caused by malassezia yeasts may be selected from seborrheic dermatitis, in particular infant seborrheic dermatitis (e.g. scab, pityriasis capitis, malassezia folliculitis, pityriasis versicolor and dandruff).

In another preferred embodiment, the avocado unsaponifiable contains at least 5% by weight, preferably at least 7% by weight, of polyhydroxy fatty alcohol, relative to the total mass of the avocado unsaponifiable.

Advantageously, the avocado unsaponifiables of the present invention contain at least 0.8% by weight, preferably at least 1% by weight sterols relative to the total mass of the avocado unsaponifiables.

The preferred route of administration of the avocado unsaponifiables or compositions of the present invention is the topical route.

Advantageously, the composition comprising avocado unsaponifiables contains at least 0.25% by weight, preferably 0.50% by weight, of avocado unsaponifiables relative to the total mass of the composition.

According to a preferred embodiment, the avocado unsaponifiables can be obtained by a process comprising at least the following steps:

i. the heat treatment step of the avocado oil concentrate is advantageously carried out at a temperature of from 60 to 90C, preferably 80C,

A step of saponifying the avocado oil concentrate in the presence of an aqueous alkali or of an aqueous alkali of the sodium hydroxide or potassium hydroxide type to obtain avocado unsaponifiables,

Optionally precipitating the soap obtained in step ii,

At least one step of extracting the product obtained in step ii or iii, wherein the avocado unsaponifiable is purified by liquid/liquid or solid/liquid extraction, at least 50% by volume of a solvent selected from the group consisting of ethyl acetate, propyl acetate and butyl acetate, preferably the solvent is ethyl acetate, relative to the total volume of the extraction solvent, and

Optionally additional purification steps of distillation and/or deodorization.

A third object of the present invention relates to the cosmetic use of an avocado unsaponifiable containing at least 50% by weight, preferably at least 60% by weight, of furan lipids relative to the total mass of the avocado unsaponifiable, for preventing, reducing and/or treating dandruff.

A fourth object of the present invention relates to the cosmetic use of a composition comprising an avocado unsaponifiable containing at least 50% by weight, preferably at least 60% by weight, of furan lipids relative to the total mass of the avocado unsaponifiable, for preventing, reducing and/or treating dandruff.

Particular embodiments of the present invention relate to avocado unsaponifiables for the prevention, reduction and/or treatment of dandruff or compositions comprising avocado unsaponifiables containing at least 50% by weight, preferably at least 60% by weight, of furan lipids relative to the total mass of the avocado unsaponifiables. Dandruff is preferably treated on healthy body and healthy scalp.

In another preferred embodiment, the avocado unsaponifiable contains at least 5% by weight, preferably at least 7% by weight, of polyhydroxy fatty alcohol, relative to the total mass of the avocado unsaponifiable.

Advantageously, the avocado unsaponifiables of the present invention contain at least 0.8% by weight, preferably at least 1% by weight sterols relative to the total mass of the avocado unsaponifiables.

The preferred route of administration of the avocado unsaponifiables or compositions of the present invention is the topical route.

Advantageously, the composition comprising avocado unsaponifiables contains at least 0.25% by weight, preferably 0.50% by weight, of avocado unsaponifiables relative to the total mass of the composition.

According to a preferred embodiment, the avocado unsaponifiables can be obtained by a process comprising at least the following steps:

i. the heat treatment step of the avocado oil concentrate is advantageously carried out at a temperature of from 60 to 90C, preferably 80C,

A step of saponifying the avocado oil concentrate in the presence of an aqueous alkali or of an aqueous alkali of the sodium hydroxide or potassium hydroxide type to obtain avocado unsaponifiables,

Optionally precipitating the soap obtained in step ii,

At least one step of extracting the product obtained in step ii or iii, wherein the avocado unsaponifiable is purified by liquid/liquid or solid/liquid extraction, at least 50% by volume of a solvent selected from the group consisting of ethyl acetate, propyl acetate and butyl acetate, preferably the solvent is ethyl acetate, relative to the total volume of the extraction solvent, and

Optionally additional purification steps of distillation and/or deodorization.

The solvent system of step iv (extraction solvent) is preferably ethyl acetate.

The compositions allowing the implementation of the invention comprise a pharmaceutically or dermatologically or cosmetically acceptable carrier, i.e. a carrier compatible with the skin, may be any dosage form normally applied topically, in particular in the form of an aqueous, hydroalcoholic or oily solution, an oil-in-water or water-in-oil or multiple emulsion, a hydrogel or oleogel, a liquid anhydrous product, an oil dispersion in the aqueous phase of spheres, which spheres may be polymeric nanoparticles (e.g. nanospheres and nanocapsules), or more preferably ionic and/or nonionic lipid vesicles, a transdermal device or any other form of topical application.

The composition can have various degrees of fluidity and can have the appearance of white or colored cream, ointment, lotion, essence, paste, mousse, gel, shampoo, hair conditioner.

Advantageously, the pharmaceutically, dermatologically or cosmetically acceptable medium is a cream.

The compositions of the invention may also contain adjuvants commonly used in the pharmaceutical or dermatological or cosmetic field, such as hydrophilic or lipophilic gelling agents, hydrophilic or lipophilic active agents, thickeners, preservatives, antioxidants, solvents, fragrances, chelating agents, odor absorbers, chemical or mineral filters, mineral pigments, surfactants, polymers, silicone oils and dyes. The amounts of these different adjuvants are those conventionally used in the field under consideration, for example from 0.01% to 20% of the total mass of the composition. Depending on their nature, these adjuvants may be incorporated into the fatty phase, the aqueous phase, the lipid vesicles and/or the nanoparticles.

As oils which can be used in the composition for carrying out the invention, mention may be made of mineral oils, oils of vegetable origin (apricot oil, sunflower seed oil, plum oil), oils of animal origin, synthetic oils, silicone oils and fluorinated oils (perfluoropolyethers). Fatty alcohols (cetyl alcohol), fatty acids and waxes (beeswax) may also be used as fats.

As emulsifiers and co-emulsifiers which can be used in the present invention, mention may be made, for example, of polyethylene glycol esters of fatty acids (for example PEG-40 stearate, PEG-100 stearate), polyol esters of fatty acids (for example glycerol stearate and sorbitan tristearate).

As hydrophilic gelling agents, mention may be made in particular of carboxyvinyl polymers (carbomers), acrylic acid copolymers (for example acrylic acid ester/alkyl acrylate copolymers), polyacrylamides, polysaccharides, natural gums and clays, and as lipophilic gelling agents, mention may be made of modified clays (for example bentonites, fatty acid metal salts, hydrophobic silica and polyethylene).

The mode of administration, dosage and optimal dosage form of the compounds and compositions according to the invention can be determined according to criteria normally considered in formulating a pharmaceutical, dermatological or cosmetic treatment suitable for a patient, such as the area of skin to be treated, tolerance to treatment, skin type.

Advantageously, the avocado unsaponifiables according to the invention can be obtained according to the methods described in international patent application WO 2004/012696, patent FR2678632 and international patent application WO 2013/014344.

For example, avocado unsaponifiables can be obtained from avocado concentrates treated using the following method:

-saponifying avocado concentrate in the presence of an alkaline ethanol solution of sodium hydroxide or potassium hydroxide type;

-washing with water;

Purification by liquid/liquid extraction in the presence of a solvent such as Dichloroethane (DCE) or methyl isobutyl ketone (MIBK) (the method described in patent FR2678632 for DCE, the method described in patent application WO2013/014344 for MIBK);

the solvents and residual impurities can be removed by distillation/deodorization to obtain a purified unsaponifiable fraction.

Avocados used as a basis for the preparation of avocado oil may preferably be subjected to a pre-dewatering or drying step, advantageously at a temperature in the range of-50 ℃ to 75 ℃. Methods of extracting avocado oil are known to those skilled in the art. Avocado oil can be extracted in particular by cold pressing or by the use of solvents at low temperatures.

Avocado oil concentrate itself can be obtained by vacuum molecular distillation (typically between 10 ^-3 mbar and 10 ^-1 mbar), and advantageously between 150 ℃ and 350 ℃, typically at a distillation temperature between 180 ℃ and 260 ℃, or by cold crystallization. The concentrate obtained is then advantageously subjected to a heat treatment at a temperature between 40 and 150 ℃, for example between 80 and 130 ℃.

The invention also relates to a non-therapeutic cosmetic hair care method for preventing and/or treating dandruff comprising the administration of an avocado unsaponifiable matter or a composition comprising an avocado unsaponifiable matter as defined above, in particular comprising the administration of said unsaponifiable matter or a composition comprising said unsaponifiable matter to the hair.

The present invention also relates to a method for the prevention and/or treatment of conditions and diseases caused by malassezia yeasts, comprising the administration, in particular the topical administration, to a subject in need thereof, of an effective amount of an avocado unsaponifiable as defined above or of a composition comprising an avocado unsaponifiable. The conditions and diseases caused by malassezia yeasts are as defined above.

Cosmetic uses and cosmetic care methods according to the invention are typically performed on healthy skin or healthy parts of the body and are not therapeutic.

The invention relates in particular to the treatment of conditions and diseases caused by malassezia yeasts.

Another object of the present invention relates to a process for preparing avocado unsaponifiables comprising at least the steps of:

i. the heat treatment step of the avocado oil concentrate is advantageously carried out at a temperature of from 60 to 90C, preferably 80C,

A step of saponifying the avocado oil concentrate in the presence of an aqueous alkali or of an aqueous alkali of the sodium hydroxide or potassium hydroxide type to obtain avocado unsaponifiables,

Optionally precipitating the soap obtained in step ii,

At least one step of extracting the product obtained in step ii or iii, wherein the avocado unsaponifiable is purified by liquid/liquid or solid/liquid extraction, at least 50% by volume of a solvent selected from the group consisting of ethyl acetate, propyl acetate and butyl acetate, relative to the total volume of the extraction solvent, and

Optionally additional purification steps of distillation and/or deodorization.

The solvent of step iv is preferably ethyl acetate.

Alternatively the heat treatment of step i. may be performed on the avocado oil prior to the concentration step and/or on the avocado used as a basis for the preparation of the oil.

The following examples are intended to illustrate the invention in a non-limiting manner.

Examples

Example 1 determination of minimum inhibitory concentration of Malassezia furfur in liquid Medium of avocado unsaponifiables and other products

This example is intended to investigate the effect of the avocado unsaponifiables according to the invention on malassezia furfur compared to another avocado product (avocado oil concentrate) and to two other soybean products (soybean oil concentrate and soybean unsaponifiables).

Process for preparing soybean oil concentrate

The crude or refined soybean oil is subjected to molecular distillation treatment under high vacuum (between 10 ^-3 mbar and 10 ^-2 mbar) and at distillation temperatures between 200 ℃ and 300 ℃.

The compounds shown in the following table were obtained.

TABLE 1

Preparation method of soybean unsaponifiable matter

The soybean concentrate or the byproducts of soybean oil refining (see patent application WO 2012/104319) obtained by the above method are treated as follows:

-saponifying the soy concentrate in the presence of an alkaline ethanol solution such as sodium hydroxide or potassium hydroxide to eliminate residual fatty acids;

-washing with water;

purification by liquid/liquid extraction in the presence of a solvent such as Dichloroethane (DCE) or methyl isobutyl ketone (MIBK) (the method described in patent application WO2012/104319 is used for MIBK);

removing the solvent and residual impurities by distillation/deodorization, obtaining the purified unsaponifiable fraction shown in the table below.

TABLE 2

Preparation method of avocado concentrate

The crude avocado oil obtained according to the method described in application WO 2004/012696 is treated by molecular distillation under high vacuum (about 5.10 ^-3 mbar) and a distillation temperature of about 250 ℃. The resulting concentrate was subjected to a temperature of 80 ℃.

The compounds shown in the following table were obtained.

TABLE 3 Table 3

Preparation method of avocado unsaponifiable matter

The first step comprises saponifying the avocado concentrate obtained using the method described above. For this purpose, avocado oil concentrate, then water and 50% potassium hydroxide are introduced into the reactor in sequence. The system was then refluxed with stirring, and then, after cooling, sodium chloride was added. A separation step of filtration or decantation is then carried out to recover the fraction comprising unsaponifiable matter. The precipitate was then extracted with ethyl acetate. The unsaponifiable is then recovered by evaporation of the solvent. Subsequently, the product is subjected to a deodorizing step by injecting 100 ℃ steam under vacuum conditions of 30 to 50 mbar.

TABLE 4 Table 4

Scheme for the production of a semiconductor device

The Minimum Inhibitory Concentration (MIC) of the different test products was determined using a method suitable for 96-well plate liquid medium. MIC measurement studies were performed according to GLYcoDiag technique using the microbial strain malassezia furfur as an organism (cf. American Type Culture Collection (ATCC): 14521). Cultures were reconstituted according to the instructions of the collection providing the reference strain. The following products were tested, soy concentrate, soy unsaponifiable, avocado concentrate.

Preparation of samples and test microorganisms

The various products listed above were previously dissolved in olive oil at a final concentration (expressed in weight%) in the medium of 1%, 0.5%, 0.25%, 0.1%, 0.05% and 0.01%.

An analytical blank was prepared and then used in the same manner as the test sample:

-a blank corresponding only to the microbial environment;

-a blank consisting of olive oil, prepared at 5% (w/w) directly in a microbial culture medium associated with each microbial strain;

control group consists of The composition was prepared at 5% (w/w) directly in the microbial medium associated with each microbial strain. Phenoxyethanol is a compound known to inhibit the growth of malassezia furfur.

To determine the MIC of the test product, 6 serial dilutions of the test product were performed directly in medium (96 well microplate) intended to promote growth of malassezia furfur strains. Each dilution point was then contaminated with the test strain at a rate of about 1.10 ⁵ cfu/mL per well. Finally, the test samples were incubated at 32.5 ± 2.5 ℃ for 48 hours, taking care to respect the respiration type of the facultative aerobics strain.

Results

At the end of the incubation period, the presence or absence of turbidity indicates the state of microbial growth. The last dilution corresponding to no growth of malassezia furfur was kept as the Minimum Inhibitory Concentration (MIC).

Study was performed with n=3. The results of the study are shown in the following table.

TABLE 5

No inhibition was detected

The avocado unsaponifiables proved to have a MIC of 0.25% for malassezia furfur strains, which is lower than that obtained with the known antifungal agents phenoxyethanol. On the other hand, neither the two concentrate samples tested, the soy concentrate and the avocado concentrate, showed inhibitory activity against malassezia furfur strains. Notably, the soybean unsaponifiables also had no inhibitory activity against malassezia furfur, thus demonstrating the specificity of the avocado unsaponifiables activity according to the present invention.

Claims (9)

1. An avocado unsaponifiable matter for use in preventing and/or treating pathologies and diseases caused by Malassezia yeasts, wherein the avocado unsaponifiable matter contains at least 50% by weight, preferably at least 60% by weight, of furanic lipids relative to the total mass of the avocado unsaponifiable matter. 2. A composition comprising avocado unsaponifiable matter containing at least 50% by weight, preferably at least 60% by weight, of furanic lipids relative to the total mass of the avocado unsaponifiable matter for use in preventing and/or treating pathologies and diseases caused by Malassezia yeasts. 3. A composition comprising avocado unsaponifiable matter for use according to claim 2, characterized in that it contains at least 0.25% by weight, preferably 0.50% by weight, of avocado unsaponifiable matter relative to the total mass of the composition. 4. Avocado unsaponifiable matter for use according to claim 1 or a composition comprising avocado unsaponifiable matter for use according to claim 2 or 3, characterized in that the pathologies and diseases caused by Malassezia yeasts are selected from seborrheic dermatitis, in particular infantile seborrheic dermatitis, such as cradle cap, pityriasis capitis, Malassezia folliculitis, pityriasis versicolor and dandruff. 5. Avocado unsaponifiable matter for use according to claim 1 or 4 or a composition comprising avocado unsaponifiable matter for use according to any one of claims 2 to 4, characterized in that the avocado unsaponifiable matter contains at least 5% by weight, preferably at least 7% by weight, of polyhydroxylated fatty alcohols relative to the total mass of the avocado unsaponifiable matter. 6. Avocado unsaponifiable matter for use according to any one of claims 1 and 4 to 5 or a composition comprising avocado unsaponifiable matter for use according to any one of claims 2 to 5, characterized in that the avocado unsaponifiable matter or the composition comprising avocado unsaponifiable matter is applied topically. 7. Avocado unsaponifiable matter for use according to any one of claims 1 and 4 to 6 or a composition comprising avocado unsaponifiable matter for use according to any one of claims 2 to 6, characterized in that the avocado unsaponifiable matter is obtained by a process comprising at least the following steps: i. a heat treatment step of the avocado oil concentrate, advantageously carried out at a temperature ranging from 60°C to 90°C, preferably 80°C, ii. a step of saponifying the avocado oil concentrate in the presence of an ethanolic or aqueous alkali solution of the sodium hydroxide or potassium hydroxide type to obtain an avocado unsaponifiable, iii. an optional step of precipitating the soap obtained in step ii., iv. at least one step of extraction of the product obtained in step ii. or iii., wherein the avocado unsaponifiable matter is purified by liquid/liquid or solid/liquid extraction using at least 50% by volume of a solvent chosen from ethyl acetate, propyl acetate and butyl acetate relative to the total volume of the extraction solvent, and v. Optional additional purification steps of distillation and/or deodorization. 8. A method for preparing avocado unsaponifiable matter, comprising at least the following steps: i. a heat treatment step of the avocado oil concentrate, advantageously carried out at a temperature ranging from 60°C to 90°C, preferably 80°C, ii. a step of saponifying the avocado oil concentrate in the presence of an ethanolic or aqueous alkali solution of the sodium hydroxide or potassium hydroxide type to obtain an avocado unsaponifiable, iii. an optional step of precipitating the soap obtained in step ii., iv. at least one step of extraction of the product obtained in step ii. or iii., wherein the avocado unsaponifiable matter is purified by liquid/liquid or solid/liquid extraction using at least 50% by volume of a solvent chosen from ethyl acetate, propyl acetate and butyl acetate relative to the total volume of the extraction solvent, and v. Optional additional purification steps of distillation and/or deodorization. 9. The method for preparing avocado unsaponifiable matter according to claim 8, wherein the extraction solvent in step iv. is ethyl acetate.