Pomegranate extract and cosmetic use thereof

Abstract

The invention discloses a pomegranate extract and a cosmetic application thereof. The present invention relates to a pomegranate extract comprising: i. At least 10% by weight of punicalagin relative to the total weight of the dry extract; and ii at least 10% by weight ellagic acid, based on the total weight of the dry extract; and wherein the weight ratio [ellagic acid / punicalagin] ranges from 0.5 to 2. The invention also relates to a method for preparing the extract. Another object of the invention is a preparation comprising said extract and at least one water-miscible organic solvent preferably selected from the group consisting of lower alcohols containing from 2 to 8 carbon atoms and in particular from 2 to 6 atoms. The invention also relates to a composition comprising said extract or preparation; a process for the cosmetic treatment of keratin materials comprising the step of applying said composition; and the cosmetic use of the extract.

Description

[0001] This application is a divisional application of the invention application with application number "202080067965.6" and invention name "Pomegranate extract and its cosmetic uses". Technical Field

[0002] The present invention relates to the field of cosmetology, and in particular to a pomegranate extract and a preparation method thereof, a composition comprising the extract, and a cosmetic use thereof as an antioxidant or anti-free radical agent. Background Art

[0003] Antioxidants are used in cosmetics to fight free radicals ( - 2. HO o etc.), these free radicals can lead to a chain reaction that can damage keratin materials in particular and induce cell aging more generally.

[0004] The role of antioxidants is therefore to capture free radicals and transform them into substances that are harmless to human keratin materials. In fact, antioxidants neutralize reactive oxygen species that are constantly generated by metabolism. These reactive oxygen species (ROS) damage biological mechanisms (especially at the protein or lipid level) and induce oxidative stress. This in turn contributes to the development and acceleration of tissue aging, especially through the appearance of wrinkles.

[0005] Among the exogenous factors capable of promoting the formation of reactive oxygen species, mention may be made of solar rays.

[0006] Antioxidants are therefore used in various cosmetic fields, such as anti-aging, protection against oxidative stress and in particular exogenous stress due to sun exposure, or anti-pigmentation (the synthesis of melanin is an oxidative process).

[0007] The generation of reactive oxygen species thus causes damage to proteins or lipids and in particular contributes to accelerated cellular ageing of keratin materials, in particular the skin and / or the appendages.

[0008] In particular, the effects of oxidative stress are to adversely affect cellular respiration and lead, inter alia, to accelerated skin aging, in particular dull and / or grey skin tone, uneven skin tone, loss of skin radiance and / or clarity, premature formation of wrinkles or fine lines, loss of skin flexibility, softness and elasticity, the appearance of pigmentation spots, in particular actinic pigmentation spots.

[0009] The effects of oxidative stress can also manifest as a reduction in hair vitality and / or a deterioration in its appearance, particularly a dull appearance.

[0010] Many antioxidants already exist, such as tocopherol (vitamin E) or its derivatives, vitamin C or its derivatives, carotenoids, ubiquinone, green tea, etc.

[0011] Pomegranate extracts are also known from the prior art as antioxidant active agents, in particular FR 3031901 describes a pomegranate extract obtained with a mixture of 70% w / w ethanol / 30% w / w water, containing not more than 1.93% ellagic acid, the weight ratio [ellagic acid / punicalagins A and B] being equal to 0.2, this extract being.

[0012] However, there is a need for alternative antioxidants that are more effective than those of the prior art, making it possible in particular to protect human keratin materials (skin and / or its appendages) from the harmful or unpleasant effects of oxidative stress. Summary of the invention

[0013] The Applicant has surprisingly demonstrated that a pomegranate extract has good antioxidant properties and in particular free radical scavenging properties by protecting skin lipids from UVA lipid peroxidation, the extract comprising at least 10% by weight of punicalagins, based on the total weight of the dry extract; and at least 10% by weight of ellagic acid, based on the total weight of the dry extract; wherein the weight ratio [ellagic acid / punicalagins] ranges from 0.5 to 2.

[0014] Furthermore, the extracts according to the invention may be used to prevent and / or treat signs of skin aging.

[0015] Additionally, the extracts according to the invention may be used to prevent and / or reduce the appearance of dullness and / or uneven skin tone.

[0016] Further advantages of the extracts or preparations according to the invention as described below are good stability properties, in particular at 40° C., over a period of two months, and / or the ready solubility of the extracts in cosmetic compositions, in particular at 25° C.

[0017] Therefore, a subject of the present invention is a pomegranate extract comprising:

[0018] i. at least 10% by weight of punicalagins based on the total weight of the dry extract; and

[0019] ii. at least 10% by weight of ellagic acid based on the total weight of the dry extract; and

[0020] The weight ratio [ellagic acid / punicalagin] ranges from 0.5 to 2.

[0021] Another subject of the present invention is a process for preparing a pomegranate extract according to the invention, comprising at least the following steps:

[0022] i. Provide pomegranate peel;

[0023] ii. extracting at least punicalagin and ellagic acid from the peel with at least 99.5% ethanol at a temperature ranging from 37°C to 45°C within 2 to 5 hours;

[0024] iii. Filter and repeat step ii. at least twice; and

[0025] iv. Optionally, drying the filtrate obtained at the end of step iii. under vacuum at a temperature ranging from 35°C to 40°C.

[0026] Another subject of the invention is a preparation comprising an extract according to the invention and at least one water-miscible organic solvent, preferably chosen from lower alcohols containing from 2 to 8 carbon atoms and in particular from 2 to 6 atoms.

[0027] The invention also relates to a composition, in particular a cosmetic composition, comprising an extract or a preparation according to the invention in a physiologically acceptable medium.

[0028] Another subject of the invention is a method for the cosmetic treatment of keratin materials, in particular the skin, comprising the step of applying to keratin materials, in particular the skin, a composition comprising a pomegranate extract according to the invention or a preparation according to the invention.

[0029] The invention also relates to the cosmetic use of an extract according to the invention in a composition comprising a physiologically acceptable medium:

[0030] - Acts as an antioxidant or anti-free radical agent;

[0031] - as an agent for preventing and / or treating signs of skin aging;

[0032] -Prevents and / or reduces the appearance of dull and / or uneven skin tone.

[0033] definition

[0034] The term "keratinous material" refers to the skin, hair, eyelashes and nails.

[0035] The term "skin" refers to the skin of the whole body, including the scalp, mucous membranes and semi-mucous membranes, and appendages of the skin of the whole body. In particular, the skin of the chest, neck and face, hands, armpits, and especially the facial skin is considered in the present invention.

[0036] The term "appendages" is understood to mean head hair, body hair, eyelashes, nails, and preferably head hair.

[0037] As used herein, the term "treating" or "treatment" refers to any action intended to improve a person's comfort or well-being. Thus, the term encompasses reducing, alleviating or inhibiting the symptoms of aging skin, but is limited to cosmetic treatments.

[0038] For the purposes of the present invention, the term "prevent" refers to reducing the risk of a phenomenon occurring.

[0039] The term "antioxidant" refers to a compound that reduces or prevents oxidation of other chemical compounds. Oxidation is part of a redox reaction that transfers electrons from one substance to an oxidizing agent. This reaction can produce free radicals. An antioxidant can specifically be an anti-free radical agent.

[0040] A "free radical" is a chemical species that has one or more unmatched electrons in its outer shell, such as an oxygen radical. Oxygen radicals are specifically:

[0041] a. Singlet oxygen ·OO·;

[0042] b.Superoxide radical anion O2·-;

[0043] c. Hydroxyl radical HO·;

[0044] d. Hydroxyl peroxide free radical HO2·;

[0045] e. Peroxide free radicals (ROO·) and alkoxy free radicals (RO·), where R is a carbon-based chain.

[0046] "Anti-free radical" refers to compounds that neutralize free radicals that are formed.

[0047] As used in this application, the term "oxidative stress" encompasses all damage caused by an increase in oxygen free radicals in a subject.

[0048] For the purposes of the present invention, the term "punicalagin" refers to a mixture of the two diastereoisomers punicalagin A and B. They belong to the polyphenol family and are in particular complex ellagitannins, formed by glucose linked to ellagic acid and gallic acid, with a molar mass of about 1084 gmol-1, formed by isomers of 2,3-(S)-hexahydroxydibenzoyl-4,6-(S,S)-galloyl-D-glucose of formula (I).

[0049]

[0050] For the purposes of the present invention, the term "ellagic acid" refers to the polyphenol having the formula (II).

[0051]

[0052] The term "punicin" refers to a mixture of the two diastereoisomers punicin A and B. They belong to the family of polyphenols and in particular are ellagitannins designated as 4,6-(S,S)-galloyl-D-glucose of formula (III).

[0053]

[0054] The pomegranate is a fruit-bearing deciduous shrub or small tree of the Lythraceae family, growing to a height of between 5 and 10 meters (16–30 ft). The leaves are deciduous opposite or in whorls of five or six on multiple spiny branches, with short stems that are oblong-lanceolate, leathery, 1–10 centimeters (0.4–4 in) long. Showy red, white, or variegated flowers are borne singly or in clusters of up to five at the tips of the branches. Nearly rounded but with a prominent calyx at the base forming a corolla, the pomegranate fruit has a tough, leathery rind or pericarp that is essentially yellow and covered with light or dark pink or rich red. The interior is divided into compartments by membranous walls and white spongy tissue, which are filled with transparent capsules filled with sour, tasty, fleshy, juicy pulp (arils). In each capsule, there is a white or red, horny, soft or hard seed. The aril accounts for about 52% of the total fruit weight.

[0055] For the purposes of the present invention, the fruit of pomegranate, and in particular the peel, is more preferred.

[0056] In a preferred embodiment of the present invention, pomegranate fruits are collected from the vicinity of Ramban district (kanga village) during the period from September to December, more specifically at the latitude and longitude of about 32°N and 74°E. DETAILED DESCRIPTION

[0057] Pomegranate Extract

[0058] Preferably, the extract according to the invention comprises:

[0059] i. from 10% to 15% by weight of punicalagins, preferably from 10.5% to 15%, more preferably from 10.8% to 14.8%, even more preferably from 11.7% to 14.6% by weight of the total weight of the dry extract; and

[0060] ii. From 10 to 15% by weight of ellagic acid, preferably from 10.5 to 14.5%, more preferably from 10.8 to 14.8%, even more preferably from 11.2 to 14.5% by weight based on the total weight of the dry extract.

[0061] The extract according to the invention may further comprise 1% to 5% by weight of punica granatum, preferably 2% to 4.5%, even more preferably 3% to 4% by weight relative to the total weight of the dry extract.

[0062] Advantageously, the weight ratio [ellagic acid / punicalagin] ranges from 0.6 to 1.6, more preferably from 0.7 to 1.3. Even more preferably from 0.7 to 1.

[0063] In a first preferred embodiment, the extract according to the invention comprises:

[0064] i. from 11.7% to 14.6% by weight of punicalagins based on the total weight of the dry extract, and

[0065] ii. from 11.2% to 14.5% by weight of ellagic acid, based on the total weight of the dry extract,

[0066] And wherein the weight ratio [ellagic acid / punicalagin] ranges from 0.6 to 1.6, more preferably from 0.7 to 1.3, even more preferably from 0.7 to 1.

[0067] In a second preferred embodiment, the extract according to the invention comprises:

[0068] i. from 11.7% to 14.6% by weight of punicalagins based on the total weight of the dry extract, and

[0069] ii. from 11.2% to 14.5% by weight of ellagic acid, based on the total weight of the dry extract, and

[0070] iii. from 3% to 4% by weight of pomegranate peel tannin, based on the total weight of the dry extract,

[0071] And wherein the weight ratio [ellagic acid / punicalagin] ranges from 0.6 to 1.6, more preferably from 0.7 to 1.3, even more preferably from 0.7 to 1.

[0072] The pomegranate extract according to the invention is either in the form of an ethanol extract or in the form of a dry extract.

[0073] The term "dry extract" refers to an extract containing no more than 7% by weight of solvent relative to the total weight of the dry extract, preferably no more than 5% by weight, more preferably no more than 3% of solvent relative to the total weight of the dry extract. In a preferred embodiment, the dry extract contains no more than 1% by weight of solvent relative to the total weight of the dry extract. In another preferred embodiment, the dry extract does not contain any solvent (i.e. 0%).

[0074] The term "solvent" refers to aqueous solvents, organic solvents and mixtures thereof.

[0075] As the aqueous solvent, water may be mentioned.

[0076] As organic solvents, mention may be made of alcohol solvents, especially monohydric alcohols in C2-C5 selected from ethanol, propanol, isopropanol, butanol and pentanol, and mixtures thereof.

[0077] Preparation method of pomegranate extract

[0078] Another object of the present invention is a method for preparing a pomegranate extract according to the present invention, comprising at least the following steps:

[0079] i. Provide pomegranate peel;

[0080] ii. extracting at least punicalagin and ellagic acid from the peel with at least 99.5% ethanol at a temperature ranging from 37°C to 45°C within 2 to 5 hours;

[0081] iii. Filter and repeat step ii. at least twice;

[0082] iv. Optionally, drying the filtrate obtained at the end of step iii. under vacuum at a temperature ranging from 35°C to 40°C.

[0083] Advantageously, the ethanol in step ii. has a moisture content of less than 0.5%, more preferably less than 0.2%.

[0084] Preferably, the pomegranate peel provided at step i. is a dry peel in the form of a powder, which particularly comprises from 1% to 5% by weight of punicalagins based on the total weight of the dry peel powder and from 1% to 5% by weight of ellagic acid based on the total weight of the dry peel powder, more preferably, from 2% to 3% by weight of punicalagins based on the total weight of the dry peel powder and from 1% to 4% by weight of ellagic acid based on the total weight of the dry peel powder.

[0085] In a preferred embodiment, the weight ratio [peel / anhydrous ethanol] is 1:5.

[0086] Advantageously, the temperature of extraction step ii. ranges from 40 to 43°C, more preferably 42°C.

[0087] The filtration in step iii. is carried out according to conventional filtration methods well known to those skilled in the art, for example, by means of a Buchner funnel.

[0088] Preferably, the temperature of the drying step iv. ranges from 37°C to 39°C, more preferably 38°C.

[0089] In a specific embodiment, the method for preparing the pomegranate extract according to the present invention comprises the following steps:

[0090] v. Provide pomegranate peel;

[0091] vi. extracting at least punicalagin and ellagic acid from the peel with at least 99.5% ethanol at a temperature ranging from 37°C to 45°C within 2 to 5 hours;

[0092] vii. Filter and repeat step ii. at least twice;

[0093] viii. Optionally, drying the filtrate obtained at the end of step iii. under vacuum at a temperature ranging from 35°C to 40°C.

[0094] Preparation

[0095] The invention also relates to a preparation comprising an extract according to the invention and at least one water-miscible organic solvent, preferably chosen from lower alcohols containing from 2 to 8 carbon atoms and in particular from 2 to 6 atoms.

[0096] More preferably, the solvent is selected from glycerol, ethanol, butylene glycol, dipropylene glycol, ethoxydiglycol and mixtures thereof, even more preferably selected from butylene glycol, dipropylene glycol, ethoxydiglycol and mixtures thereof.

[0097] In a more preferred embodiment, the solvent is selected from butylene glycol, dipropylene glycol and a mixture thereof.

[0098] Advantageously, the weight ratio [solvent / dry extract] ranges from 95:5 to 99.9999:0.0001, preferably from 96:4 to 99.999:0.001, more preferably from 97:3 to 99.99:0.01.

[0099] The extract may constitute from 0.0001% to 5% by weight of the total weight of the preparation, calculated as the weight of the dry extract, and the at least one solvent may constitute from 95% to 99.9999% by weight of the total weight of the preparation, preferably, the extract may constitute from 0.001% to 4% by weight of the total weight of the preparation, calculated as the weight of the dry extract, and the at least one solvent may constitute from 96% to 99.999% by weight of the total weight of the preparation, more preferably, the extract may constitute from 0.01% to 3% by weight of the total weight of the preparation, calculated as the weight of the dry extract, and the at least one solvent may constitute from 97% to 99.99% by weight of the total weight of the preparation.

[0100] Composition

[0101] The invention also relates to a composition, in particular a cosmetic composition, comprising an extract or a preparation according to the invention in a physiologically acceptable medium.

[0102] The extract according to the invention may be present in the composition in an amount from 0.0001% to 5% by weight of the dry extract relative to the total weight of the composition, preferably from 0.001% to 4% by weight of the dry extract relative to the total weight of the composition, more preferably from 0.01% to 3% by weight of the dry extract, even more preferably from 0.5% to 2.5% by weight of the dry extract.

[0103] The preparation according to the invention may be present in the composition in an amount ranging from 0.1% to 60% by weight relative to the total weight of the composition, preferably from 0.5% to 50% by weight relative to the total weight of the composition, more preferably from 1% to 40% by weight.

[0104] The composition may be a cosmetic composition comprising a physiologically acceptable medium, especially a medium compatible with the skin and scalp.

[0105] According to a particular embodiment, the pH of the cosmetic composition is between 4 and 7.5, in particular between 4.5 and 7, and in particular between 4.7 and 6.5.

[0106] The physiologically acceptable medium of the composition may more particularly comprise water and optionally a physiologically acceptable water-soluble organic solvent chosen, for example, from lower alcohols containing from 2 to 8 carbon atoms and in particular from 2 to 6 carbon atoms, such as ethanol, isopropanol, propanol, butanol; polyethylene glycols and polyols having from 6 to 80 ethyleneoxy units, such as propylene glycol, isopentyl glycol, butylene glycol, glycerol and sorbitol.

[0107] The water-soluble organic solvent may account for from 0.5% to 25% by weight of the total weight of the composition, preferably from 1% to 20% by weight of the total weight of the composition, more preferably from 1.5% to 15% by weight of the total weight of the composition.

[0108] In a preferred embodiment, the composition comprises a preparation as defined above and a physiologically acceptable medium, which medium may more particularly comprise water and optionally an additional physiologically acceptable water-soluble organic solvent. In such an embodiment, the additional water-soluble organic solvent may represent from 0.5% to 25% by weight of the total weight of the composition, preferably from 1% to 20% by weight of the total weight of the composition, more preferably from 1.5% to 15% by weight of the total weight of the composition.

[0109] Galenic forms

[0110] In a preferred embodiment, the composition according to the present invention is administered topically.

[0111] The carrier may be of varying nature depending on the type of composition under consideration.

[0112] More particularly, as regards compositions for external topical application, they may be aqueous, hydro-alcoholic or oily solutions, solutions or dispersions of the lotion or serum type, emulsions of liquid or semi-liquid consistency of the emulsion type (obtained by dispersing a fatty phase in an aqueous phase (O / W) or vice versa (W / O)), or suspensions or emulsions of soft, semi-solid or solid consistency of the cream type, aqueous or anhydrous gels, microemulsions, microcapsules, microparticles, or vesicular dispersions of the ionic and / or non-ionic type.

[0113] These compositions were prepared according to the general methods.

[0114] When the composition of the present invention is an emulsion, the proportion of the fatty phase can range from 5% to 80% by weight, and preferably from 10% to 50% by weight relative to the total weight of the composition. The oil, emulsifier and co-emulsifier used in the composition in the form of an emulsion are selected from those conventionally used in the field of cosmetics and / or dermatology. Emulsifiers and co-emulsifiers may be present in the composition in a proportion ranging from 0.3% to 30% by weight and preferably from 0.5% to 20% by weight relative to the total weight of the composition.

[0115] When the composition of the invention is an oily solution or gel, the fatty phase may represent more than 90% of the total weight of the composition.

[0116] The composition used according to the invention may constitute a skin care composition and in particular a cleansing, protection, treatment or care cream (for example a day cream, night cream, make-up remover, foundation cream or sunscreen) for the face, hands, feet, the major anatomical folds or the body; a fluid foundation, a make-up remover, a protective or care body lotion or a sunscreen; a skin care lotion, gel or mousse, such as a cleansing lotion.

[0117] Auxiliary agents

[0118] In a known manner, the galenical forms for topical application may also contain adjuvants customary in the cosmetic, pharmaceutical and / or dermatological fields, such as hydrophilic or lipophilic gelling agents, hydrophilic or lipophilic active agents, emulsifiers, preservatives, additional antioxidants different from the compounds of the invention, solvents, fragrances, fillers, ultraviolet (UV) screening agents, odor absorbers and colorants. The amounts of these various adjuvants are those commonly used in the field under consideration, for example from 0.01% to 20% of the total weight of the composition. Depending on their nature, these adjuvants may be introduced into the fat phase and / or into the aqueous phase.

[0119] The composition may also contain oils such as mineral oils, for example hydrogenated polyisobutene and liquid petrolatum; vegetable oils, for example shea butter, sunflower seed oil and the liquid portion of apricot kernel oil; animal oils, for example perhydrosqualene, synthetic oils, in particular purcellin oil, isopropyl myristate and ethylhexyl palmitate; fluoro oils, for example perfluoropolyethers. The composition may also contain unsaturated fatty acids or fatty alcohols; waxes; silicone compounds, for example silicone oils; resins; gums.

[0120] As previously stated, the composition according to the invention may also comprise a UV-screening agent or photoprotectant active in UVA and / or UVB light in the form of an organic or inorganic compound, the inorganic compound optionally being coated to make it hydrophobic.

[0121] In a preferred embodiment, the composition according to the invention further comprises at least one ingredient chosen from: silicone fats, such as oils, gums and silicone waxes; non-silicone fatty substances, such as oils, pastes and waxes of vegetable, mineral, animal and / or synthetic origin; fatty acids having 8 to 32 carbon atoms; esters and synthetic ethers, in particular of the formula R1COOR2 and R1OR2, in which R1 represents the residue of a fatty acid containing from 8 to 29 carbon atoms and R2 represents a branched or unbranched hydrocarbon chain containing from 3 to 30 carbon atoms; straight or branched hydrocarbons of mineral or synthetic origin; fatty alcohols having from 8 to 26 carbon atoms; some water; C2-C6 alcohols; glycols, such as propylene glycol, ketones; thickeners, emulsifiers, surfactants, gelling agents, cosmetic active ingredients, fragrances, fillers, dyes, moisturizers, vitamins, polymers.

[0122] Beauty Methods

[0123] Another subject of the invention is a cosmetic treatment method for keratin materials, in particular the skin, comprising the step of applying to keratin materials, in particular the skin, a composition comprising a pomegranate extract or preparation as previously defined.

[0124] In particular, the treatment method aims to prevent and / or reduce the effects of oxidative stress or free radicals, in particular those resulting from UV radiation, on keratin materials, in particular the skin.

[0125] The invention also relates to a cosmetic treatment method for the skin aimed at preventing and / or treating the signs of skin aging, in particular induced by oxidative stress.

[0126] Among the signs of skin aging induced in particular by oxidative stress, mention may be made of loss of skin firmness and / or elasticity and / or tone and / or suppleness, the formation of wrinkles and fine lines, expression lines, in particular on the forehead and in the space between the eyebrows, perioral wrinkles and fine lines, and / or sagging in the area around the lips, in particular in the upper lip area (area between upper lip and nose), a dull appearance of the complexion, and a papery appearance of the skin.

[0127] The method also aims at preventing skin pigmentation, in particular caused by oxidative stress, especially caused by UV radiation, and comprises at least one step consisting in applying a composition comprising a pomegranate extract as previously defined to the skin showing signs of skin aging.

[0128] In particular, the method according to the invention aims to prevent and / or reduce pigmented spots of the skin, in particular actinic spots; to lighten the skin; to prevent dull skin tone and / or grey skin tone, and / or to improve the brightness and / or evenness of the skin tone; to improve the radiance and / or transparency of the skin; to improve the flexibility, softness and / or elasticity of the skin; and / or to prevent and / or reduce wrinkles and / or fine lines.

[0129] Cosmetic Uses

[0130] The invention also relates to the cosmetic use of a pomegranate extract according to the invention as an antioxidant or anti-free radical agent, in particular in a composition containing a physiologically acceptable medium, said extract being intended to prevent and / or reduce the effects of oxidative stress or free radicals on keratin materials, in particular the skin.

[0131] The invention also relates to the cosmetic use of a pomegranate extract according to the invention, in particular in a composition containing a physiologically acceptable medium, as an anti-aging agent, in particular as an agent for preventing and / or treating signs of skin aging.

[0132] The invention also relates to the cosmetic use of a pomegranate extract according to the invention, in particular in a composition containing a physiologically acceptable medium, for preventing and / or reducing the appearance of dullness and / or uneven skin tone.

[0133] Throughout the description, the expression “comprising a” or “containing a” means “comprising at least one” or “containing at least one” unless stated otherwise.

[0134] In this description, the expression "at least one" means "one or more".

[0135] In this description and the following examples, unless otherwise indicated, percentages are by weight, and value ranges written as "between" or "from" include the upper and lower limits specified. The various ingredients are mixed before their shaping in an order and under conditions readily determined by the skilled artisan.

[0136] We will now give specific examples which illustrate the present invention but which are in no way limiting.

[0137] Unless otherwise stated, all percentages given in the examples are by mass, and unless otherwise stated, temperatures are ambient temperature (20° C.) and are expressed in degrees Celsius, and unless otherwise stated, pressures are atmospheric pressure. BRIEF DESCRIPTION OF THE DRAWINGS

[0138] Figure 1 : Schematic diagram of the preparation method of pomegranate extract according to the present invention.

[0139] Figure 2 : Reduction of lipid peroxidation with the pomegranate extract according to the invention compared to ellagic acid alone. Note: The value in % indicated above each bar (in the graph) is the % protection provided by the raw material tested with respect to prolonged UV A exposure.

[0140] Example

[0141] Example 1: Preparation of pomegranate extract according to the present invention

[0142] Dried pomegranate peel (1 kg) was extracted with 5 liters of ethanol (Proof 99.5%) at 42°C for a short period of 4 hours under stirring at 800 rpm. The obtained ethanol extract was filtered through a Buchner funnel containing cotton cloth (mesh size: 20 microns). The filtered extract was evaporated in vacuum at 38°C to obtain a brown amorphous powder. The extraction was repeated sequentially under the above conditions for two consecutive times. The combined dry extract consisted of major phenolic compounds, namely: ellagic acid and punicalagin. A schematic diagram of the preparation method of the pomegranate extract according to the present invention is shown in Figure 1 Presented in.

[0143] The specifications of the extract according to the present invention are as follows:

[0144] Table 1. Extract specifications

[0145]

[0146] The ratio of these two compounds, ellagic acid and punicalagin, varied with the different organic extraction solvents used, namely: absolute alcohol: 99.5% and distilled spirits: 95.0-96.0%, methanol, ethyl acetate and aqueous acetone. Therefore, the extraction was carried out with different organic solvents. The results showed that absolute alcohol (proof: 99.5%) provided an extract with the appropriate amount and ratio of ellagic acid / punicalagin.

[0147] *

[0148] Table 2 - Comparison of different organic solvents

[0149]

[0150] Furthermore, the ratio of the two compounds, ellagic acid and punicalagin, varies with the temperature of the extraction step and the temperature of the drying step. Therefore, the extraction step and the drying step are performed at different temperatures (° C.).

[0151] Table 3 - Comparison of different extraction temperatures

[0152]

[0153] Table 4 - Comparison of different drying temperatures

[0154]

[0155]

[0156] Example 2: Antioxidant activity of the extract according to the invention obtained in Example 1

[0157] a. Lipid Peroxidation Test

[0158] The protective potential of the pomegranate extract according to the invention obtained according to Example 1 against UVA-induced lipid peroxidation was evaluated and compared with the protection of pure ellagic acid against UVA-induced lipid peroxidation.

[0159] Normal human fibroblasts were treated with 0.001% of the pomegranate extract according to the invention or with 3 μM of pure ellagic acid for 24 hours and then exposed to a UVA dose that induced no more than 20% cell death.

[0160] A control was performed which consisted of normal human fibroblasts exposed to a UVA dose that induced no more than 20% cell death.

[0161] The release of 8-isoprostane was measured 2 hours and 30 minutes after exposure. Figure 2 Presented in.

[0162] The control (UV exposure) showed a release of 100% of 8-isoprostaglandins, and 0% protection against lipid peroxidation, whereas the treatment with the pomegranate extract according to the invention showed a lower release of 58% of 8-isoprostaglandins, and a higher protection of 42% against lipid peroxidation.

[0163] Ellagic acid showed 65% release of 8-isoprostane, and 35% protection against lipid peroxidation.

[0164] Therefore, the pomegranate extract according to the invention shows better protection against lipid peroxidation than ellagic acid alone.

[0165] Example 3: Extracts according to the present invention compared to extracts outside the present invention (extracted with 95% ethanol) Evaluation of antioxidant activity (extracted with 99.5% ethanol)

[0166] The technique for evaluating the antioxidant activity of the compounds used according to the invention is performed according to well-known methods (J. of Photochemistry and Photobiology B: Biology 57 (2000) 102-112 TOBI et al.: Glutathione modulates the level of free radicals produced in UVA-irradiated cells). The technique uses a fluorescent probe, a marker of overall intracellular oxidative stress, 2′-7′-dichlorofluorescein diacetate (DCFH-DA).

[0167] principle

[0168] The use of DCFH-DA as a marker of oxidative stress is based on its physicochemical properties. It is a non-polar and non-ionic molecule that is able to diffuse through cell membranes. Once inside the cell, DCFH-DA will be hydrolyzed by intracellular esterases to produce a non-fluorescent compound: DCFH or 2,7-dichlorodihydrofluorescein. In the presence of reactive oxygen species, DCFH is rapidly oxidized to produce a highly fluorescent compound: DCF or 2,7-dichlorofluorescein.

[0169] program:

[0170] The extract according to the present invention obtained in Example 1 (extracted with 99.5% ethanol) and the extract obtained in Example 1 Keratinocytes were treated with an extract other than the present invention (extracted with 95% ethanol)

[0171] At confluence, keratinocytes were incubated in culture medium in the presence of the extracts to be tested at 37° C., 5% CO 2 for 24 hours.

[0172] Incorporation of DCFH-DA

[0173] Keratinocytes pretreated with each extract were rinsed and then incubated in the presence of DCFH-DA in the dark.

[0174] Exposure to UVA

[0175] After this incubation, the DCFH-DA solution was removed and the cells were then exposed to 2 J / cm 2 Observation: Unexposed control plates were stored in the dark at room temperature.

[0176] Fluorescence measurement

[0177] The fluorescence of DCF was assessed by spectrofluorometry (excitation: 480 nm; emission: 530 nm) immediately after exposure to UVA.

[0178] result

[0179] The results of the photoprotective efficacy are presented in the following Table 4 as % fluorescence reduction relative to control cells exposed to UV A. Two samples were measured and the average value determined.

[0180] Table 5. Results

[0181]

[0182] The above results revealed that the extract of Example 1 obtained with 99.5% ethanol had better antioxidant activity with respect to UVA-induced oxidative stress, with the fluorescence inhibition of DCF being higher than that obtained with the extract of Example 1 extracted with 95% ethanol.

[0183] Thus, the pomegranate extract according to the invention induces a better active photoprotection of the skin relative to the untreated control and the comparative extract outside the invention.

[0184] Example 4: Cosmetic composition comprising the extract according to the invention obtained in Example 1

[0185] An anti-aging aqueous gel for skin is prepared, comprising (by weight %):

[0186] Carbopol 4%

[0187] Pomegranate extract obtained according to Example 1 0.5%

[0189] Water qs 100%

[0190] When applied to the face, the composition protects the skin from UVA-induced stress.

Claims

1. A pomegranate extract, comprising: i. at least 10% by weight of punicalagins based on the total weight of the dry extract; and ii at least 10% by weight of ellagic acid based on the total weight of the dry extract; and The weight ratio [ellagic acid / punicalagin] ranges from 0.5 to 2.

2. The extract according to claim 1, wherein The extract contains: i. from 10% to 15% by weight of punicalagins, based on the total weight of the dry extract; and ii. from 10 to 15% by weight of ellagic acid based on the total weight of the dry extract.

3. The extract according to claim 1 or 2, wherein The extract further comprises from 1 to 5% by weight of pomegranate tannin based on the total weight of the dry extract.

4. An extract according to any one of the preceding claims, wherein The weight ratio [ellagic acid / punicalagin] ranges from 0.6 to 1.6, preferably from 0.7 to 1.3, more preferably from 0.7 to 1.

5. An extract according to any one of the preceding claims, wherein The extract is an ethanol extract or a dry extract.

6. A preparation comprising an extract as defined in any one of claims 1 to 5 and at least one water-miscible organic solvent preferably chosen from lower alcohols containing from 2 to 8 carbon atoms and in particular from 2 to 6 atoms.

7. Preparation according to the preceding claim, wherein The at least one water-miscible organic solvent is selected from glycerol, ethanol, butylene glycol, dipropylene glycol, ethoxydiglycol and mixtures thereof, preferably selected from butylene glycol, dipropylene glycol, ethoxydiglycol and mixtures thereof.

8. The preparation according to any one of claims 6 or 7, wherein The weight ratio [solvent / dry extract] ranges from 95:5 to 99.9999:0.0001, preferably from 96:4 to 99.999:0.001, more preferably from 97:3 to 99.99:0.

01.

9. The preparation according to any one of claims 6 to 8, wherein The extract accounts for from 0.0001% to 5% by weight of the total weight of the preparation, calculated on the weight of the dry extract, and the at least one solvent accounts for from 95% to 99.9999% by weight of the total weight of the preparation, preferably, the extract accounts for from 0.001% to 4% by weight of the total weight of the preparation, calculated on the weight of the dry extract, and the at least one solvent accounts for from 96% to 99.999% by weight of the total weight of the preparation, more preferably, the extract accounts for from 0.01% to 3% by weight of the total weight of the preparation, calculated on the weight of the dry extract, and the at least one solvent accounts for from 97% to 99.99% by weight of the total weight of the preparation.

10. A composition, in particular a cosmetic composition, comprising an extract as defined in any one of claims 1 to 5 or a preparation as defined in any one of claims 6 to 9 in a physiologically acceptable medium.

11. The composition according to claim 10, wherein The composition further comprises at least one ingredient chosen from silicone fats, such as oils, gums and silicone waxes; non-silicone fatty substances, such as oils, pastes and waxes of vegetable, mineral and / or synthetic origin; fatty acids having 8 to 32 carbon atoms; esters and synthetic ethers, in particular of the formula R1COOR2 and R1OR2, in which R1 represents the residue of a fatty acid containing from 8 to 29 carbon atoms and R2 represents a branched or unbranched hydrocarbon chain containing from 3 to 30 carbon atoms; straight or branched hydrocarbons of mineral or synthetic origin; fatty alcohols having from 8 to 26 carbon atoms; some water; C2-C6 alcohols; glycols, such as propylene glycol, ketones; thickeners, emulsifiers, surfactants, gelling agents, cosmetic active ingredients, fragrances, fillers, dyes, moisturizers, vitamins, polymers.

12. The composition according to any one of claims 10 or 11, wherein The extract constitutes from 0.0001% to 5% by weight of the dry extract of the total weight of the composition, preferably from 0.001% to 4% by weight of the dry extract of the total weight of the composition, more preferably from 0.01% to 3% by weight of the dry extract, even more preferably from 0.5% to 2.5% by weight of the dry extract.

13. The composition according to any one of claims 10 or 11, wherein The preparation represents from 0.1% to 60% by weight of the total weight of the composition, preferably from 0.5% to 50% by weight of the total weight of the composition, more preferably from 1% to 40% by weight of the total weight of the composition.

14. Cosmetic use of the extract according to any one of claims 1 to 5 as an antioxidant or anti-free radical agent.

15. Cosmetic use of the extract according to any one of claims 1 to 5 as an anti-aging agent.

16. Cosmetic use of an extract according to any one of claims 1 to 5 for preventing and / or reducing the appearance of dullness and / or uneven skin tone.

17. A method for the cosmetic treatment of keratin materials, in particular the skin, comprising the step of applying to said keratin materials, in particular the skin, a composition according to any one of claims 10 to 13.

18. A method for preparing the pomegranate extract according to any one of claims 1 to 5, comprising at least the following steps: i. Provide pomegranate peel; ii. extracting at least punicalagin and ellagic acid from the peel using ethanol having a degree of at least 99.5% at a temperature ranging from 37°C to 45°C within a period of 2 to 5 hours; iii. Filter and repeat step ii at least twice; and iv. Optionally, drying the filtrate obtained at the end of step iii. under vacuum at a temperature ranging from 35°C to 40°C.

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