EP2173319A2

EP2173319A2 - Cosmetic composition with anti-radical properties and corresponding application method

Info

Publication number: EP2173319A2
Application number: EP08827887A
Authority: EP
Inventors: Stéphane Jacques Joseph MASSON; Anne Marie Catherine Simonnet; Anne Marie Guillemette De La Sayette; Christine Anne-Maria Raymonde Brunet
Original assignee: Yves Saint Laurent Parfums SA
Current assignee: Yves Saint Laurent Parfums SA
Priority date: 2007-07-06
Filing date: 2008-07-03
Publication date: 2010-04-14
Also published as: FR2918274A1; US8475848B2; US20100247464A1; FR2918274B1; WO2009024671A3; BRPI0814061A2; WO2009024671A2

Abstract

The invention relates to a cosmetic composition for topical use with anti-radical properties and comprising at least one natural vegetable extract in a cosmetically acceptable medium, characterised in that said at least one natural vegetable extract is insoluble. Cosmetic compositions.

Description

COSMETIC COMPOSITION HAVING ANTI-RADICAL PROPERTIES AND CORRESPONDING APPLICATION METHOD

TECHNICAL AREA

The present invention relates to the general technical field of cosmetic products for topical use, used in particular on the skin, hair and nails, and may in particular be in fluid or liquid form, dough, semi-liquid or semi-pasty, gel, powder or foam.

The present invention relates in particular to the general technical field of cosmetic products containing anti-radical substances conferring them anti-radical properties.

The present invention relates to a cosmetic composition for topical use having anti-radical properties and comprising at least one plant extract of natural origin in a cosmetically acceptable medium.

The present invention also relates to the use of a plant extract of natural origin in a cosmetic composition having anti-radical properties.

The present invention finally relates to a method of applying a cosmetic composition for topical use having anti-radical properties. In its preferential application, the cosmetic composition according to the invention constitutes a makeup product for the skin, the nails and the hair, having anti-radical properties.

PRIOR ART

In general, the parts of the human body in contact with the wider environment, including the skin, hair and nails are the most sensitive to external elements that may have adverse effects.

The skin is also particularly vulnerable to attacks by free radicals. These oxidizing molecules can be dangerous in case of excess and play an important role in skin aging.

Free radicals, generated by the normal functioning of the human body, are usually balanced with antioxidant molecules. The natural mechanisms of antioxidant defense of the skin involve molecules such as vitamin E, vitamin C, selenium, enzymes ... These antioxidant molecules have the main property of trapping the free radicals of the body in order to maintain the balance between free radicals and antioxidant molecules.

Free radicals are also produced under the influence of external elements such as pollution, tobacco or UV rays. In some situations, the density of antioxidants decreases, while the level of free radicals increases. The natural balance between the free radicals and the antioxidant molecules is then disturbed creating an oxidative stress. This stress makes them aggressive towards the body, particularly with respect to the fundamental elements of the skin, such as in particular keratinocytes, fibroblasts, collagen and elastin. The consequences of aggression of the skin by free radicals are multiple and the most common are its loss of strength and elasticity.

There is therefore a certain interest to bring, especially to the skin, substances with anti-radical properties to strengthen its natural defenses and help fight against free radicals.

The demand for cosmetics is constantly evolving, and there is a trend to promote more products that protect the skin and other body surfaces exposed to external elements. It turns out that consumers are eager to use a cosmetic product, and in particular a makeup product, which is also a real "skin care". The basic properties of a makeup product, which are to provide color, camouflage and correct small skin imperfections, can now be accompanied by biological properties, such as, for example, the protection of the skin vis- free radicals.

It also turns out that products carrying a "natural" image are particularly in demand. With regard to certain synthetic compounds incorporated in cosmetic compositions, products of natural origin or containing natural compounds are increasingly appreciated by consumers.

These different reasons have led the cosmetics industry to offer on the cosmetics market products containing natural or naturally occurring substances and having anti-radical properties, in particular to meet the trend mentioned above. Thus we already know cosmetic compositions containing these substances capable of trapping free radicals produced in excess by the body during external aggression (pollution, tobacco, UV).

Such compositions typically contain at least one antioxidant substance, in particular of plant origin such as an anthocyanin. Anthocyanin is usually incorporated in pure form or isolated form from a plant extract.

However, these purified molecules are often synthetic molecules, which can be obtained in particular by biotechnology. They are no longer associated with the image of natural products in the eyes of consumers.

We also know the difficulties associated with the low availability on the market of plant extracts of natural origin that can be integrated into cosmetic compositions, especially in anhydrous makeup cosmetic compositions, further limiting their use.

It is therefore difficult, at present, to obtain cosmetic compositions having anti-radical properties, especially for make-up products, containing a plant extract of natural origin, even though the need seems important.

SUMMARY OF THE INVENTION

The object of the invention is therefore to remedy the various disadvantages listed above, and to propose a novel cosmetic composition having anti-radical properties and containing at least one plant extract of natural origin that can be incorporated easily and on a large scale. in cosmetic compositions. Another object of the invention is to propose a novel cosmetic composition capable of proposing a particularly simple and effective anti-radical action.

Another object of the invention is to provide a new cosmetic composition incorporating natural compounds from plants widely present in the natural state and readily available.

Another object of the invention is to propose a new cosmetic composition offering a wide range of incorporation of substances with anti-radical properties.

Another object of the invention is to propose a new cosmetic composition having a broad spectrum of application and use in the field of cosmetics.

Another object of the invention is to propose a new use of a plant extract of natural origin in a cosmetic composition for topical use.

Another object of the invention is to propose a new process for applying a cosmetic composition for topical use having anti-radical properties.

The objects assigned to the invention are attained by means of a cosmetic composition for topical use having anti-radical properties and comprising at least one plant extract of natural origin in a cosmetically acceptable medium, characterized in that said at least one a plant extract of natural origin is insoluble. The objects assigned to the invention are also achieved by using at least one plant extract of natural origin that is insoluble as an anti-radical agent in a cosmetic composition for topical use to confer properties anti-radical.

The objects assigned to the invention are furthermore attained by means of a method of applying a cosmetic composition for topical use intended to protect the epidermis, the nails and the hair against free radicals, characterized in that it consists in applying to said epidermis, nails and hair a cosmetic composition as defined above.

Other advantages and objects of the invention will appear in more detail on reading the description which follows and with the aid of examples and tests which are provided for purely explanatory and non-limiting purposes.

BEST MODE OF REALIZING THE INVENTION

The invention relates to a cosmetic composition, defined according to the invention as a composition intended for cleaning, protecting, perfuming, maintaining the body in good condition, modifying the appearance and / or odor of the human body.

A cosmetic composition, as defined in the invention, can therefore be a hygiene product (toothpaste, deodorant, shower gel, soap, shampoo), a care product (anti-wrinkle cream, day cream, night cream, cream moisturizing, floral water, scrub, milk, beauty mask, lip balm, tonic), a hair product (hair conditioner, straightener, gel, oil, hairspray, mask, dye), a perfume (cologne, water perfume), a make-up product (concealer, self-tanner, eyeliner, make-up, make-up, kohl, mascara, powder, bleaching product) skin, lipstick and / or nail polish) and / or a solar product (after-sun and sun creams, oils or lotions).

The invention relates to a cosmetic composition for topical use, that is to say acting at the place where it is applied namely on an outer surface of the body.

The invention relates to a cosmetic composition defined in a cosmetically acceptable medium. By "cosmetically acceptable medium" is meant a set of ingredients well known to those skilled in the art that can be mixed, while respecting the constraints of the individual use of each ingredient, the constraints related to the possible interactions between the ingredients and the ingredients. legislative constraints associated with certain ingredients (maximum incorporation dose, ...). All the ingredients, commonly used in cosmetic compositions, can thus constitute a cosmetically acceptable medium within the meaning of the invention, insofar as the aforementioned constraints are respected.

The composition of the invention has anti-radical properties. The term "anti-radical" in the meaning of the invention means "having an action against free radicals naturally produced by the human body". In other words, the anti-radical property is an antioxidant property associated with a substance or a compound. An antioxidant substance is capable of decreasing or preventing the oxidation of other chemicals in the body, this oxidation reaction producing free radicals that can lead to destructive chain reactions. Antioxidants are able to stop these chain reactions by oxidizing with free radicals and thus annihilating their action. According to the invention, the cosmetic composition makes it possible to reduce the level of free radicals by neutralizing the excess produced by the body in the event of external stress (pollution, solar radiation, stress, tobacco, alcohol, etc.).

The present invention relates to a cosmetic composition comprising at least one plant extract of natural origin. For the purposes of the present invention, the plant extract of natural origin is a preparation obtained by maceration of all or part of a plant in a solvent liquid and by subsequent evaporation of the solvent. By "plant extract of natural origin" is meant a plant extract derived from the extraction of a plant found in nature or cultivated. The constituent molecules of the plant extract of natural origin are themselves of natural origin, as opposed to synthetic molecules.

The invention relates to a cosmetic composition for topical use having anti-radical properties and comprising at least one natural plant extract in a cosmetically acceptable medium characterized in that said at least one plant extract of natural origin is insoluble. By plant extract of insoluble natural origin is meant a plant extract of natural origin that can not be dissolved, or at least substantially dissolved, in water, in an aqueous medium or in an oily medium. In other words, the plant extract of the present invention is substantially insoluble in the cosmetic medium in which it is incorporated. With this technique, it is particularly easy to incorporate the plant extract of natural origin into a cosmetic composition, in particular in a cosmetic composition anhydrous or containing very little water as for the products of makeup, especially because of the very good compatibility of the insoluble natural plant extract with the other components of this anhydrous cosmetic composition. Preferably, according to the invention, said at least one plant extract of natural origin contains at least one anti-radical substance. In other words, said at least one plant extract of natural origin contains a substance capable of reducing the unusually high rate of free radicals following the intervention of external elements (pollution, solar radiation, stress, tobacco, alcohol, ...) to or towards its natural balance in the body.

Alternatively, the anti-radical substance may be contained in a component of the composition other than the plant extract of natural origin, without departing from the scope of the invention.

According to the invention, said at least one anti-radical substance described above is a polyphenol, a natural antioxidant constituting a family of organic molecules widely present in the plant kingdom. Polyphenols, produced by the secondary metabolism of plants, are characterized by the presence of several phenolic groups, associated with more or less complex structures, high molecular weight. They are natural antioxidants divided into several sub-families which can all be incorporated, alone or in combination, into the composition according to the invention, such as: phenolic acids, flavanones, tannins and anthocyanins.

However, it is entirely possible, without departing from the scope of the invention, to use antioxidants of origin other than polyphenols. This may include vitamin C, vitamin E, enzymes and / or carotenoids. Alternatively, it may also be envisaged to use antioxidants of animal origin also having a recognized anti-radical action. Advantageously, according to the cosmetic composition of the invention, said at least one plant extract of natural origin is derived from the extraction of plants selected from those containing polyphenols.

According to the invention, said at least one plant extract of natural origin derived from the extraction of plants containing polyphenols, is preferably chosen from plant extracts containing at least one or more of the following molecules: fustine, dihydrorobinetin, brazilin, braziléine , Sulfuretin, Sulfurine (Sulfuretin 6-glucoside), Palasitrin

(3 ', 6-diglucoside sulfuretine), corseopside (4'-butin glucoside), apegininidine, luteolinidine, cyanidin, pelargonidin, fisetinidine, gallic acid, ellagic acid, valonic acid, proanthocyanidols and profisetinidine.

These polyphenolic molecules belong to different biochemical families of polyphenols including flavonoids, anthocyanins and tannins. We give hereinafter a nonlimiting list, usable in a cosmetic composition according to the invention:

Flavonoids:

Flavonoids include neo-flavonoids, chalcones, aurones, flavanones, flavonols and flavanols. The general formula of flavonones is as follows:

Among the flavonoids, there are especially fustine and dihydrorobinétine. Brazilin is the main molecule in the neo-flavonoid family and is oxidized to red braziléine.

Aurones, another subfamily of flavonoids, includes in particular sulfuretine, sulfurine (6-glucoside of sulfuretine) and palasitrine (3 ', 6-diglucoside of sulfuretine).

Corseopside (4'-glucoside butine) belongs to the family of flavonoids but is part of the biochemical family of chalcones.

Anthocyanins:

The general formula of anthocyanins is as follows:

With R1, R2, R3, R4, R5, R6 and R7 = H, OH or OCH _3.

Apegininidine, luteolinidine, cyanidin, pelargonidin and fisetinidine are also members of the anthocyanin family and have the following formulas:

With:

The tannins:

The tannins, derived from gallic acid and other polyphenolic acids, have a very variable chemical structure, but always with a polyphenolic part. Some tannins are called hydrolysable tannins and give after hydrolysis either gallic acid or ellagic acid.

Gallic acid belongs to the family of hydrolysable tannins, in particular the family of ellagitannins. Ellagic acid and valonic acid also belong to the family of ellagitannins. Other tannins are condensed tannins. These are polymers resulting from the condensation of flavan-3-ols units and their general formula is as follows:

With R1 and R2 = H or OH (catechols or gallocatechols)

Proanthocyanidols are part of the condensed tannin family. This family includes profisetinidine.

According to the invention, the cosmetic composition of the invention preferably contains at least one plant extract of natural origin derived from the extraction of dyeing plants.

Advantageously, said at least one plant extract of natural origin is derived from the extraction of at least one plant selected from Cosmos, Pernambuco, Oak, Quebracho or Sorghum, containing one or more anti-cancer molecules. radicals as defined above. The concentration of polyphenols in these plants is higher than that conventionally found in most plants.

The cosmos is an annual plant native to Mexico that contains flavonoids (aurones and chalcones), especially sulfuretine, sulfurine (6-glucoside sulfuretine), palasitrin (3 ', 6-diglucoside sulfuretine) and corseopside (4'-glucoside butine).

In accordance with the invention, the extract of Pernambuco used comes from a tree of the family of legumes that are found in particular in Brazil in the province of Pernambuco. The wood scraps are recovered for the manufacture of the extract as used in the cosmetic composition of the invention. The Pernambuco extract preferably contains brazilin and red braziléine.

The Oak extract, used in the cosmetic composition of the invention, is advantageously derived from the cupules of the glans. The cups of the species of oak used to make the extract of the invention in the composition of the invention are of the size of an apple and very rich in tannins, in particular in ellagic acid and valonic acid.

Quebracho is a tree whose name comes from the Spanish quiebra hacha (breeze hatchet) because of the very hardness of its wood. It is found in

South America. The extract obtained from this tree and used in the cosmetic composition of the invention is particularly rich in tannins and flavonoids. The tannins of quebracho are also used as additives in oenology. The brown color of the Quebracho extract is a mixture of hydrolysable tannins, notably gallic acid and ellagic acid, which are found mainly in glycosylated form and condensed tannins, especially profietinidin.

Sorghum, as used in the invention, is an annual grass, whose variety "dyes" used in dyeing in Africa was found in archaeological layers a thousand years old. The two most commonly used African bicolor sorghum breeds for dyeing, food and cosmetics are caudatum and kafir. Sorghum extract consists of a mixture of flavonoids of the group of anthocyanidins, which are found in free form, glycosylated, or methoxylated and condensed tannins, including fustine, dihydrorobinétine, sulfurétine, apigeninidine, luteolinidine, cyanidine pelargonidine and fisetinidine.

Preferably, the cosmetic composition of the invention may contain one or other of these extracts as defined above or a mixture of several extracts from at least two of these plants.

It is also conceivable, without departing from the scope of the invention, to use extracts from plants other than those previously mentioned. All plants naturally containing antioxidant molecules, especially polyphenols, can be used for extraction and incorporation into a cosmetic composition of the invention.

According to the cosmetic composition of the invention, said at least one plant extract of natural origin represents between substantially 0.01% to 50% of the total weight of the cosmetic composition, preferably between substantially 0.5% and 20%.

According to the cosmetic composition of the invention, said at least one plant extract of natural origin represents between approximately 0.5% and 45% of the total weight of the cosmetic composition when said cosmetic composition is in a powdery dry form of the type pressed powder, in particular in a cosmetic composition of eyeshadow.

Alternatively, when said at least one plant extract of natural origin is introduced into an anhydrous pasty formula of composition its concentration preferably varies between approximately 0.5% and 15% of the total weight of the cosmetic composition.

According to the invention, when said at least one plant extract of natural origin is introduced into a cosmetic composition of the invention in the form of an emulsion, its concentration preferably varies between substantially 0.01% and 20% by weight. total of the cosmetic composition.

In a preferred embodiment of the invention, the cosmetic composition comprises a mixture of plant extracts of natural origin derived from the extraction of at least two plants selected from Cosmos, Pernambuco, Oak, Quebracho and Sorghum, representing in total substantially 0.01% to 50% of the total weight of the cosmetic composition, more particularly between substantially 0.5% and 20% of the weight of the cosmetic composition.

The plant extracts obtained after conventional extraction processes and from the previously described plants are naturally water-soluble, very little manipulable and hardly at all possible to be incorporated in the case of anhydrous cosmetic compositions of make-up products.

In the present invention, said at least one plant extract of natural origin of the cosmetic composition is coupled to a mineral substrate, preferably calcium carbonate. Alternatively, any other insoluble mineral substrate may be coupled with said at least one plant extract of natural origin to make it insoluble. In other words, the combination of the plant extract with a mineral substrate contributes to making the plant extract substantially insoluble in the medium into which it is introduced. The use of plant extracts of natural origin insoluble in cosmetic compositions facilitate their incorporation into said compositions and in particular in anhydrous compositions or containing very little water. This coupling of the natural plant extract to a natural substrate is made sufficiently solid to prevent any subsequent release of the plant extract in the cosmetic composition in which it is incorporated.

Preferably, the cosmetic composition of the invention protects the epidermis against free radicals. In particular, the cosmetic composition is in the form of emulsion and / or cream and / or gel and / or body milk and / or powder and / or lotion and / or mask and / or balm, can be applied to the human epidermis.

Alternatively, the cosmetic composition of the invention protects the hair against free radicals. In this variant of the invention, the cosmetic composition is preferably in the form of shampoo and / or conditioner and / or gel and / or oil and / or spray and / or protection and / or hair care product for coloring and / or hair care repair and / or lotion and / or lacquer, applicable on the hair.

Alternatively, it is also conceivable that the cosmetic composition of the invention protects the nails against free radicals and is preferentially in the form of care treatment and / or repair care and / or nail polish and / or base for the varnish.

In a preferred embodiment of the invention, the cosmetic composition constitutes a makeup product for the skin and / or the hair and / or the eyelashes and / or the eyebrows and / or the nails. Preferably, said cosmetic composition is in the form of cream for beautifying the epidermis and / or lipstick and / or blush. eyelids and / or powder and / or mascara and / or liquid foundation and / or powder foundation and / or foam foundation and / or pencils and / or blush and / or eyeliner and / or nail polish. Alternatively and without departing from the scope of the invention, said cosmetic composition may be in any other form of makeup product normally used for topical application, preferably in the form of an anhydrous composition containing very little or no water.

EXAMPLES

As an illustration and in accordance with the invention, four examples of formulation of make-up products, presented in some of the aforementioned galenic forms, are given below and illustrate in more detail the preceding description. These examples are provided for purely explanatory and non-limiting purposes. The ingredients are expressed in each of the examples as a percentage of the total weight of the cosmetic composition.

Example 1 Eyeshadow Formula Containing Insoluble Natural Plant Extracts

In this anhydrous anhydrous powdery dry formula, insoluble plant extracts of natural origin are introduced at a level of 50% by total dry weight of the composition. This is a percentage much higher than the percentages of incorporation of non-insoluble plant extracts into cosmetic compositions.

Example 2 Lipstick Formula Containing Insoluble Natural Plant Extracts

In this conventional formula of lipstick, plant extracts of insoluble natural origin are introduced at a level of 6% by total dry weight of the composition. Example 3: Foundation Formula

In this conventional foundation formula, plant extracts of insoluble natural origin are introduced at a level of 6% by total dry weight of the composition.

Example 4: Facial Cream Formula

In this facial care cream formula, the sole plant extract of insoluble natural origin introduced represents 0.4% of the total dry weight of the composition.

It should be noted that in Examples 3 and 4 the compositions contain respectively 62.8% and 80.4% of water, which renders these compositions of aqueous nature and no longer anhydrous, as in Examples 1 and 2. Thus, the invention allows the introduction of plant extracts of insoluble natural origin into anhydrous cosmetic compositions such as make-up products and / or into cosmetic compositions containing water in greater or lesser amounts. The list of ingredients of the cosmetic compositions of the examples set out above is not exhaustive. The cosmetic formulation involves a large number of ingredients. The invention is obviously not limited to some of these ingredients in particular and allows the incorporation of all the known ingredients of a cosmetic composition. The cosmetic composition will obviously be adapted to the dosage form that the makeup product takes.

The invention also relates to the use of at least one plant extract of insoluble natural origin as anti-radical agent in a cosmetic composition for topical use to confer anti-free radical properties. This use according to the invention is preferably intended for the protection of the epidermis, nails and hair against environmental pollution, in all its forms (UV radiation ₁ tobacco, toxic gas,), and especially against naturally occurring free radicals. in excess by the body during external stress.

The invention relates ultimately to a method of applying a cosmetic composition for topical use for protecting the epidermis, the nails and the hair against free radicals, characterized in that it consists in applying to said epidermis, nails and hair a cosmetic composition as defined in the foregoing. The application of the cosmetic composition of the invention is made in accordance with current practices concerning cosmetic products. It will be possible in particular to apply the cosmetic composition of the invention manually or with the aid of a conventional utensil (brush, glove, comb, shovel, bomb, brush, cotton ...).

Advantageously, the anti-radical properties of plant extracts of natural origin described in the present invention were tested in tests whose details are set out below. ANTI-RADICAL EFFICIENCY TESTS

1 / Tests on the plant extract The anti-radical properties of plant extracts of natural origin used in compositions according to the invention were demonstrated by different tests carried out on both pure plant extracts and plant extracts. rendered insoluble. These studies, conducted in March 2007, were conducted on Cosmos, Quebracho and Pernambuco. 6 samples were used and their references are as follows:

Pure Cosmos Extract - lot 1024 Pure Quebracho Extract - lot 8636 Pure Pernambuco Extract - lot 05-33 Scattered Cosmos Extract 6IT06 / F001 Scattered Quebracho Extract 6IT06 / F004 Scattered Pernambuco Extract 6IT06 / F002

The objective of these tests is to highlight the anti-radical activity of pure vegetable extracts in powder form, as well as the anti-radical activity of these same extracts associated with an insoluble mineral substrate and dispersed in water. carnation oil, commonly used in cosmetic compositions of make-up products.

Material and method

The study of the activity of pure extracts was carried out using 2 biochemical tests: one is based on the reduction of 2,2-diphenyl-1-picrylhydrazyl (DPPH) by the antioxidants, and the another on the measurement of hydrogen peroxide (H ₂ O ₂ ) in the reaction media. H ₂ O ₂ is trapped by a specific "AmplexRed" reagent. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) is a stable radical compound which is reduced to 1,1-diphenyl-2-picrylhydrazine by antioxidants. This reduction is followed by the color change of the DPPH solution (optical density measurement).

AmplexRed is a compound that reacts stoichiometrically with H ₂ O ₂ , producing a fluorescent red compound, resofurin, which can be measured in fluorescence. This test makes it possible to detect small quantities of H ₂ O ₂ .

The pure extracts as well as the antioxidant references (D-tocopherol and BHA: butylated hydroxyanisole for DPPH, BHA alone for AmplexRed) were solubilized in ethanol. Controls on ethanol alone were performed to verify the absence of interference of this solvent.

MraJ.tspurs _. : _. test _. DWFNs

The products of this test were tested starting from the concentration of 1 mg / ml, within a range of reason 10. The alpha-tocopherol positive control was meanwhile tested at the concentration of 0.1 μM and the BHA at the concentration of 50 μM.

.Extxajts.pure.i _. tesj _. Hj ^ /. AmpJexRed

The products of this test were tested starting from the concentration of 1 μg / ml, within a range of reason 10. The BHA positive control was tested at concentrations of 50 and 500 μM.

The study of the activity of the extracts associated with an insoluble mineral substrate, dispersed in carnation oil, was carried out by means of a lipid peroxidation test on irradiated skin explants. This is, which is done in topical application of the products, makes it possible to study in vitro the effects of non-hydrosoluble extracts.

Cytotoxicity was previously monitored using an MTT test (3- (4,5-dimethylthiazol-2-yl) -2,5-diphenyl tetrazolium bromide (tetrazolium salt) to determine test.

Upon receipt, the skin explants were cut and cultured.

The products under test or reference (positive control = BHA) were then applied to the surface of the explants at a rate of 5 mg / cm ² and the explants were placed for 24 hours in an incubator at 37 ° C. in the presence 95% air and 5% CO ₂ . The control skin pieces did not undergo any treatment.

After incubation and washing, the explants of each series were exposed to irradiation of ultraviolet rays A and B (UVA + B). The irradiation is carried out by SOL500 Sun Simulator lamp with H2 filter and the exposure conditions are as follows:

UVA + B filter:

UVA: power 11, 5 mW / cm ² is 678.6 mJ / cm ² / minute

- UVB: power 0.78mW / cm ² is 47.1 m J / cm ² / minute Irradiation time: 21 minutes That is about 1 J / cm ² of UVB and 14J / cm ² of UVA.

Three other untreated control explants were kept out of the light. Following irradiation, the explants were incubated again for 24 h.

The epidermis was then extracted and cell viability was assessed using MTT revelation. The lipids of the epidermis were extracted with a methanol / chloroform mixture, before assaying the lipid peroxidation using a specific kit, in particular using the PeroxiDetect kit (Sigma PD1). The results are expressed in nmoles of lipid peroxides per volume of sample.

Results

Pure extracts

Extχaits.i) hearts.. Test.DPPH

++: strong reduction,> to 50%, +: 50% reduction, +/-: 25% reduction -: no reduction

The negative control, pure ethanol, did not reduce DPPH as expected. References, in particular tocopherol, have clearly reduced the DPPH. These negative and positive controls give the expected results and thus make it possible to validate the test. The 3 pure extracts, tested in the range of 1 mg / ml to 0.01 mg / ml, reduced in a dose-dependent manner the stable radical compound DPPH, ie according to the tested dose the reduction of the DPPH is different.

The approximate IC50 values for Cosmos, Quebracho and Pernambuco are 0.1 mg / ml, 0.06 mg / ml and 0.07 mg / ml, respectively.

Extxajtspurs.i.tesj.HjP ^ /. AmpJexRed

strong reduction,> 50%, + 50% reduction, +/- 25% reduction - no reduction to ARL activity)

g / ml | <f, 1 μg / ml 1 μg / ml 10 μg / ml |

The positive and negative controls gave the expected results. Notably, BHA significantly decreased the amount of free ₂ O ₂ revealed by the AmplexRed reaction (35% and 38%, respectively, of the control). The test is therefore considered valid.

The three extracts tested between 0.1 and 10 mcg / ml, decreased dose-dependent manner the amount of H ₂ θ ₂ free revealed by AmplexRed reaction.

The approximate IC50 values for Cosmos, Québracho and Pernambuco are 7.4 μg / ml, 0.7 μg / ml and 0.8 μg / ml, respectively.

Conclusion of the two tests on pure extracts: the 3 extracts tested showed an anti-radical activity interesting, since they are active at low concentration. According to the IC50, it can be concluded that the extracts of Quebracho and Pernambuco have a comparable anti-radical power, and superior to that of the extract of Cosmos.

Extracts associated with an insoluble mineral substrate: effect on lipid peroxidation

Effect on lipid peroxidation -% control + UV (inversely proportional to ARL activity)

ARL: anti free radicals

UV irradiation has resulted in a significant increase in the level of lipid peroxides in proportions usually obtained in the laboratory and this without changing the viability. It should be noted that the vehicle used for the solubilization of the products (carnation oil) did not interfere with the assay. The treatment of skin explants by reference greatly reduced the production of lipid peroxides after irradiation. This result was expected and validate the test.

The cosmos plant extract tested at a concentration of 5%, 1% and 0.2% allowed a significant reduction in the concentration of lipid peroxides. At a concentration of 1%, the cosmos plant extract decreased by almost 50% the production of lipid peroxides after irradiation.

The plant extract of Pernambuco tested at 50%, 10% and 2% significantly decreased the production of lipid peroxides. At 50% and 10%, the product was still slightly pro-oxidant. At 2%, it decreased by about 50% the production of lipid peroxides after irradiation.

The vegetal extract of Québracho tested at 50% did not show any effect while tested at 10% and 2%, it significantly decreased the production of lipid peroxides. At 10%, it decreased by about 40% the production of lipid peroxides after irradiation.

In conclusion, the plant extracts of Cosmos, Pernambuco and Québracho have protective effects against the stress induced by UV irradiation by decreasing the production of lipid peroxides. The effects of these products are visible at low concentrations.

It is also interesting to note that the Cosmos plant extract at a concentration of 1% and the plant extract of Pernambuco at a concentration of 2% make it possible to maintain a level of lipid peroxidation close to the non-irradiated control condition. Conclusion:

The various tests have demonstrated a significant anti-radical activity of the Cosmos, Quebracho and Pernambuco extracts, whether they are in the form of pure extracts (DPPH and AmplexRed biochemical tests) or associated with an insoluble substrate ( assay of lipid peroxidation on explants of irradiated skin).

Therefore, the association with a substrate does not alter the anti-radical properties of plant extracts of natural origin.

2 / Tests on the composition comprising the plant extract Following the results obtained on the extracts of Cosmos, Pernambuco and Quebracho in the context of the tests described above, a test on the anti-radical activity of an eyeshadow containing these extracts has been put in place. This is a lipid peroxidation test on skin explants, performed in August 2007.

The model of explant of human skin allows a topical application of the products to allow to study in vitro the effects of finished products, namely in this case an eyeshadow. The use of ultraviolet rays A and B

(UVA + B) leads to the production of reactive oxygen species, ie oxygen free radicals, present in the skin during exposure to the sun (O _2. , OH ^" , H ₂ O ₂ * ) - These oxygenated free radicals are partly responsible for genetic damage (DNA damage) and cell damage

(oxidation of proteins and lipids) encountered in the skin.

In fact, an increase in the level of oxygen free radicals induces a lipid peroxidation which gives rise to chain reactions inducing the formation of highly reactive species which disturb the biological functions of the membranes and lead to local phenomena. irritation and dry skin. To these direct effects of oxygen free radicals can also be added various indirect effects contributing to an acceleration of skin aging.

The objective of this study is to evaluate the anti-radical activity of an eyeshadow containing the plant extracts defined above, using a lipid peroxidation test on irradiated skin explants. The effects of this eyeshadow have been compared to an eyeshadow not containing anti-free radicals.

Material and method

Biological model:

A tummy tuck is performed on a 45-year-old woman (donor).

- Test medium: DMEM (Invitrogen 21969035), Glutamine 2 nriM, Penicillin-Streptomycin 50 IU / ml-50 μg / ml, Fetal calf serum 10%.

Samples used: - 6YI07 / B043: control eyeshadow, without colored plant extracts (replaced by a red pigment),

- 6YI07 / B042: eye shadow containing 5% Quebracho plant extract, 5% Pernambuco extract and 5% Cosmos extract.

Treatment and irradiation

A conventional lipid peroxidation test is performed on irradiated skin explants. This test, which is done by topical application of eye shadow, allows to study in vitro the effects of eyeshadow. Upon receipt, 4 cm ² skin explants are cut and cultured. The skin explants then receive different treatments. Some receive the eyeshadow control, others the eyeshadow "test" containing plant extracts, others a sunscreen of protection index 20 (IP20) serving as a positive control and other no treatment (control negative).

The treatments (eyeshadows or IP20 sunscreen) are applied at a rate of 5 mg / cm ² , and the explants are then placed for 24 hours in an incubator at 37 ^° C. in the presence of 95% of air and 5% of CO2. . After incubation and washing, the explants of each series are exposed to ultraviolet radiation type A and B (UVA + B). The irradiation is performed by a SOL500 Sun Simulator lamp with a H2 filter and the exposure conditions are as follows:

UVA + B filter: - UVA: power 10 J / cm ² - UVB: power 1 J / cm ²

Three other untreated control explants are kept out of the light. Following irradiation, the explants are incubated again for 24 hours.

After incubation, the surface of the explants is rinsed with PBS and for each explant, 3 punches of 8 mm are made and then incubated in sterile water at 62 ⁰ C for 2 minutes, in order to separate the epidermis from the dermis. An additional punch of 8 mm is made for each treatment in order to evaluate the viability of the cells by the MTT reduction test (standard protocol).

Lipid peroxidation test

The epidermis is then extracted, and the viability of the cells assessed by MTT revelation. The lipids of the epidermis are extracted with a mixture methanol / chloroform (standard protocol), before a lipid peroxidation assay using a PeroxiDetect specific kit (Sigma PD1), following the procedure recommended by the supplier. The results are expressed in nmoles of lipid peroxides per volume of sample (30 .mu.l), and then converted into percentage (%) of protection relative to the irradiated control explant.

Data processing

The raw count data is transferred and processed under the software PRISM® (Graph Pad Software). Intergroup comparisons are performed by analysis of variance (ANOVA) followed by a Dunnett multiple comparison test.

The percentage of protection is calculated according to the formula:

(control + UV - treated + UV) x 100 P% of protection = - (Control + UV - control-UV)

Results

The results of this test are shown in the table and graph below. below:

* ARL: Anti-free radicals; ** FaP: Eyeshadow * EVC: Colorful plant extracts

UV irradiation resulted in a significant increase in the level of lipid peroxides in proportions usually obtained in the laboratory. The treatment of skin explants with IP20 sunscreen (positive control) significantly decreased the production of lipid peroxides after irradiation (36% compared to the control + UV). This result was expected and validate the test.

The application of the eyeshadow control (FaP control) on the surface of the explants significantly reduced the level of lipid peroxides following irradiation in comparison with the control itself receiving irradiation (75% of the control with UV (+), p <0.05). The application of the eyeshadow containing plant extracts (FaP test with EVC) on the surface of the explants significantly reduced the level of lipid peroxides following irradiation and significantly different from the control receiving UV irradiation ( 57% of the control with UV (+), p <0.05).

In conclusion, the eyeshadow control (FaP control) can slightly protect the skin from the effects of free radicals induced by UV irradiation. On the other hand, the eyeshadow containing the plant extracts (FaP test) has a greater protective capacity against free radicals than that of the eyeshadow control. The addition of plant extracts thus accentuates the anti-free radical power of the eye shadow (see last column of the table).

The previously detailed tests have made it possible to demonstrate the anti-radical properties of plant extracts of natural origin that are insoluble and used in the cosmetic compositions according to the invention. The insoluble form of these extracts is that used in the cosmetic composition of the invention, in particular for make-up products.

This new technology applied to make-up products has many advantages. The development of these plant extracts of natural origin insoluble allows the development of makeup ranges very rich in phenolic compounds. These plant extracts of insoluble natural origin with anti-radical properties allow the realization of products extremely rich in antioxidant substances beneficial for the protection of the skin, hair and nails. The use of these plant extracts of natural origin insoluble in cosmetic compositions of the invention conveys a natural image of the cosmetic composition while providing an anti-free radical efficacy.

These plant extracts of insoluble natural origin also have the advantage of being easily incorporated in a large number of cosmetic compositions, especially in anhydrous makeup formulas. The fact of making plant extracts of natural origin insoluble also makes it possible to broaden the spectrum of action and incorporation of such compounds in the cosmetic compositions.

Indeed, these plant extracts of insoluble natural origin can easily be introduced into all galenic forms of cosmetics, and in particular in all known forms of make-up and this because of their high compatibility with these different galenic forms. The ease of their introduction into the cosmetic compositions of the invention makes them particularly useful on a large scale.

POSSIBILITY OF INDUSTRIAL APPLICATION

The invention finds its industrial application in the design and use of cosmetic products for topical use.

Claims

Cosmetic composition for topical use having anti-radical properties and comprising at least one plant extract of natural origin in a cosmetically acceptable medium, characterized in that said at least one plant extract of natural origin is insoluble.

- Cosmetic composition according to claim 1 characterized in that said at least one plant extract of natural origin contains at least one anti-radical substance.

- Cosmetic composition according to claim 2 characterized in that said at least one anti-radical substance is a polyphenol.

- Cosmetic composition according to claim 3 characterized in that said at least one plant extract of natural origin is derived from the extraction of plants selected from those containing polyphenols.

- Cosmetic composition according to claim 4 characterized in that said at least one plant extract of natural origin derived from the extraction of plants containing polyphenols is selected from plant extracts containing at least one or more molecules: fustine, dihydrorobinétine, brazilin, braziline, sulfuretine, sulfurine (6-glucoside sulfuretine), palasitrin (3 ', 6-diglucoside sulfuretine), corseopside (4'-glucoside butine), apegininidine, luteolinidine, cyanidin, pelargonidin, fisetinidine, gallic acid, ellagic acid, valonic acid, proanthocyanidins and profisetinidine. - Cosmetic composition according to claim 5 characterized in that said at least one plant extract of natural origin is derived from the extraction of dyeing plants.

- Cosmetic composition according to claim 6 characterized in that said at least one plant extract of natural origin is derived from the extraction of at least one plant selected from Cosmos, Pernambuco, Oak, Quebracho or Sorghum.

- Cosmetic composition according to any one of claims 1 to 7 characterized in that said at least one plant extract of natural origin represents between substantially 0.01% to 50% of the total weight of the cosmetic composition, preferably between substantially 0 , 5% and 20%.

Cosmetic composition according to any one of Claims 1 to

Characterized in that said at least one plant extract of natural origin represents between approximately 0.5% and 45% of the total weight of the cosmetic composition when said cosmetic composition is in a pulverulent dry form.

Cosmetic composition according to any one of Claims 1 to 8, characterized in that the said at least one plant extract of natural origin represents between approximately 0.5% and 15% of the total weight of the cosmetic composition when the said cosmetic composition is presented. in an anhydrous pasty form.

Cosmetic composition according to any one of Claims 1 to 8, characterized in that the said at least one plant extract of natural origin represents between approximately 0.01% and 20% of the total weight. of the cosmetic composition when said cosmetic composition is in the form of an emulsion.

Cosmetic composition according to claim 7, characterized in that it comprises a mixture of plant extracts of natural origin derived from the extraction of at least two plants chosen from Cosmos, Pernambuco, Oak, Quebracho and Sorghum, representing in total between substantially 0.01% to 50% of the total weight of the cosmetic composition, preferably between substantially 0.5% and 20%.

Cosmetic composition according to any one of Claims 1 to 12, characterized in that the said at least one plant extract of insoluble natural origin is associated with a mineral substrate, preferably with calcium carbonate.

Cosmetic composition according to any one of claims 1 to 13, characterized in that it constitutes a makeup product for the skin and / or hair and / or eyelashes and / or eyebrows and / or nails.

Cosmetic composition according to claim 14, characterized in that it is in the form of a cream for beautifying the epidermis and / or lipstick and / or eyeshadow and / or powder and / or mascara. and / or liquid foundation and / or powder foundation and / or foam foundation and / or pencils and / or blush and / or eyeliner and / or varnish. nails.

Cosmetic composition according to any one of Claims 1 to 13, characterized in that it protects the human epidermis against free radicals. Cosmetic composition according to claim 16, characterized in that it is in the form of emulsion and / or cream and / or gel and / or body milk and / or lotion.

Cosmetic composition according to any one of claims 1 to 13 characterized in that it protects the hair against free radicals.

- Cosmetic composition according to claim 18 characterized in that it is in the form of shampoo and / or conditioner and / or gel and / or oil and / or spray and / or hair care of protection and / or hair care coloring and / or hair care repair and / or lotion and / or lacquer.

- Cosmetic composition according to any one of claims 1 to 13 characterized in that it protects the nails against free radicals.

Cosmetic composition according to claim 20, characterized in that it is in the form of a care treatment and / or repairing care and / or nail polish and / or base for the varnish.

- Use of a plant extract of insoluble natural origin as an anti-radical agent in a cosmetic composition for topical use to give it anti-free radical properties.

- A method of applying a cosmetic composition for topical use for protecting the epidemic, the nails and the hair against free radicals, characterized in that it consists in applying to said epidermis, nails and hair a cosmetic composition such as as defined in any one of claims 1 to 22.